GPS User Issue Detection & Evaluation (GUIDE) Tool (2024)

68805/17/2024MarineUSER: At 0545Lt vessel lost gps signal today on 17 may 2024 and every 10-15 seconds the signal is loosing hence no position data available for the vessel. The Gps fail error causing gyro failure and AIS failure as well. This is continuing till now. Currently vessel at anchor in Port said anchorage.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference05/20/202468605/14/2024MarineUser: Vessel equipped with 2 Kongsberg DPS 232 GPS units. Simultaneous loss of both. Vessel also equipped with 2 X Furuno GP-170 units - no alarms present - PDOP = 1.3m
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference05/20/202468004/24/2024CommunicationsUSER: VSAT Communications including Data and voice lost over a period of approx. 36 hours. Informed by Technician of Marlink Service Desk that vessel has "GPS jamming (GPS interface) and the VSAT will not work properly and the Antenna can't detect any satellite until the vessel is headed out of the zone." Re-boot of ACU seemed to break the jammed connection, and signal to the VSAT restored after Antenna was able to lock onto beam.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/30/202467904/18/2024MarineUSER: Bab El Mandeb strait
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/22/202467504/12/2024NoneUSER: CALLER REPORTED A POSSIBLE CYBER SECURITY ATTACK ON THE VESSEL APL EAGLE AT THE INCIDENT LOCATION. THE CALLER STATED THEY EXPERIENCED AN ERRATIC TRACK LINE ON THE VESSELS CHART DISPLAY, THAT SEEMED TO TRY AND TAKE THE VESSEL OFF OF THEIR COURSE. THIS INTERFERENCE TOOK PLACE FOR A FEW MINUTES, AND THEN WENT BACK TO NORMAL. THIS VESSEL EXPERIENCED THIS A FEW MONTHS AGO WHILE IN THE SAME AREA. THE VESSEL IS A US FLAGGED SHIP WHO'S PORT OF REGISTRY IS WILMINGTON, DELAWARE. THE VESSEL HAS NEVER BEEN TO THE UNITED STATES, AND OPERATES IN JEBEL ALI, DUBAI. THE U.S. COAST GUARD ACTIVITIES EUROPE DOES THERE INSPECTIONS.WILMINGTON, DELAWARE WAS USED AS THE INCIDENT LOCATION, BUT THE INCIDENT ACTUALLY OCCURED AT THE COORDINATES PROVIDED IN THE PERSIAN GULF.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/15/202467404/11/2024MarineUSER: Our vessel on entering Gulf of Aqaba experiencing intermittent GPS spoofing & later after an hour GPS signal has been completely lost.Vessel using GPS for navigation purpose.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/15/202467604/11/2024MarineUSER: On 11th April, 1838 UTC, MT Toya while approaching the port of Ras Tanura, KSA experienced loss of position (suspected GPS interference) which was rectified within one minute. However, the HDOP high alert remained for another 10-15 minutes.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/15/202466904/09/2024MarineUSER: While underway, vessel had faced No.1 & 2 GPS no fix alarm occurred at 0710LT on 03/Apr/2024. and still GPS signal not restored properly.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202468104/09/2024AutomobileUSER: Constant intermittent issues with GPS in the San Gabriel valley of California near Los Angeles. This is constant and frustrating. Never a problem with using GPS in New York. Please fix
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information04/30/202467704/07/2024MarineUSER: MV APL EAGLE, 170.0M Geared Containership, 1700 TEU, experienced GPS position anomaly indicative of GPS Spoofing today 12th APRIL 2024, 1200LT (ZD-3)/0900UTC. Sea area: Persian Gulf. 0912Z Position: Latitude: 26-19.9N Long. 051-39.3E Noted similar errors to the previously reported incident 9th November 2023. Presented on ECDIS screen as erratic track. Noted Position errors of more than 0.5nm on ECDIS history track. Suspected interference with Differential signal. Both GPS units appear to be functioning normally, and errors cleared after a few minutes.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/15/202467304/06/2024OtherUSER: We are noticing a disturbance in our GPS systems when we use it to navigate trough traffic. Since I cannot find anything online about it I thougt I would report it here.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202467204/05/2024AutomobileUSER: Driving between my home and destination, both in South Surrey, BC, Canada, the vehicle location was reflected significantly off of the road, causing the map application to be ‘confused’, telling me to make turns that didn’t make sense. Several times during the 15 minute drive, the vehicle map icon appeared to ‘jump’ to a new location (within meters).
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202466804/02/2024MarineUSER: Pls be informed that today, on 02 Apr 2024, during the day, vessel’s GPS exposed with jamming of the signals at the Port Said anchorage area. This is not only our problems, same situation on board other vessels in vicinity.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202466704/01/2024MarineUSER: Interference with GPS Signal of all Vessel’s in the vicinity for approx. 1.5hrs
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202466603/31/2024MarineUSER: Vessel had faced GPS signal jamming when navigating near Juaymah Terminal, Saudi Arabia. This was experienced from 28th evening Saudi arab time till 31st morning time intermittently with long outage time. Presently the signal is stable.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202466403/30/2024TransportationGPS disruptions in the East Mediterranean when vessel is underway from Alexandria, Egypt to Port Said, Egypt. This is one of the many occurrence of GPS disruptions until vessel reach Port Said Southern Holding Anchorage at 30 Mar 2024 2136UTC. It is more frequent when vessel was approaching Port Said Southern Holding Anchorage. Moreover, even at anchorage area, still we are having GPS signal disruptions and also other vessels in the vicinity is heard on VHF Ch 16 having the same issue.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Unknown Interference04/08/202466103/25/2024ResearchUSER: Received adequate satellite counts but gps reported velocity and other quality metrics were very unstable and not conducive to drone flight
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Insufficient Information04/08/202467003/23/2024TransportationUSER: As I am driving my GPS will randomly shoot across maybe 1/2 mile off course and keep trying to recalculate. This recently began beginning 3/23/24 and happens intermittently to this day. I have deleted the navigation applications (Google Maps, Waze, and Apple Maps) and reinstalled them and they still do this. I have checked my phone for updates and Apple has nothing to report. It was even stranger when my car began doing this 3/30/24 and it is at the same time my phone GPS goes haywire. I am not sure what is going on.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202465803/19/2024OtherUSER: It is believed that my address is being GPS Spoofed by a NC/Alamance County Emergency Management employee. I have lost over $1,000 in merchandise. Alamance County Sheriff's Office refuses to investigate as it is believe to be 1 of the sheriff's relatives. This has been an ongoing issue. This time it was a FedEx driver for the 2nd time in a week.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Unknown Interference04/08/202465903/19/2024NoneUSER: We have continuous alarms concerning 5G base stations. Alarms: GNSS Clock Output Unavailable, GNSS Locked Satellites Insufficient, all over Cyprus. No satellites are tracked and bts go to holdover. Many alarms clear after some time and some restore back after gps board reset. We've also checked longitude and latitude of a BTS and it was shown on a wrong place. Please inform us for any problems in the area of Cyprus. Thank you!!!
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Unknown Interference04/08/202465703/17/2024CommunicationsUSER: I'm an engineer. At this approximate time my gps device (android maps) would move my identified location by several hundred meters every few seconds and constantly switch directions I was traveling. There were few tall buildings in my area. My vehicle gps locator (hyundai) also was giving errors that it could not determine a stable location. My friends gps (apple maps) was doing the same. And two rideshare drivers (uber) reported to us that they, too, were experiencing the same exact disruption say that time and were having trouble navigating and finding their riders. By 8AM, everything was normal in this area. This could have been an illegal spoofing incident.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference03/18/202465603/14/2024CommunicationsUSER: Apple phone Waze and Apple Maps
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information03/18/202465403/11/2024CommunicationsUSER: While jogging big energy level from mobile phone radio app in german language (Crystal Missions producent) in Poland forest or like sky is the limit. More hot than usual. Someone 5 times turned off this radio app by stop button in my phone while jogging. Area is always international tourist attraction for many joggers and big RTCN Jemiołów tower transmitter 320 meters with military zone.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference03/18/202466503/09/2024AutomobileUSER: GPS on DASHCAM is not receiving any signal, unable to track speedometer or other warnings on the DASHCAM through GPS. GPS display on DASHCAM screen is marked with a Red Cross. Everything else with DASHCAM works perfectly, eg; TIME/DATE and basic video recording. This error has been happening for about a month. I am finding it disturbing as I rely on the Safety Features the DASHCAM provides through GPS.Is there any explanation as to why it has stopped working.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User Equipment04/08/202465303/06/2024MarineUSER: GPS Disruption was intermittent, lasted less than 1 min
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference03/11/202465202/23/2024MarineUSER: Reports loss of GPS in the South China Sea.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202465502/14/2024CommunicationsUSER: Our ADVA OSA5430 loses GPS signal every night between 2am and 5am since at least Jan 2024. The 360 degree antenna on the roof has been checked and has nothing near and is pointing straight up. Signal level is good during the day.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference03/18/202465102/09/2024MarineUSER: 1. Vessel’s Name: Lucina Providence2. Type of Incident: GPS Signal interference 3. Date and Time of Incident: 23 Feb 2024/ 1028LT ( 23 Feb 2024/ 0228 UTC)4. Ship’s Position: 07°32.5’N; 108°13.1’E5. Status: Underway, full speed at sea.6. Brief Description of the Incident: Interference with GPS Signal of all Vessel’s in the vicinity for approx. 38 Min 7. Others: a) GPS signal interference to both DGPS receiver and independent AIS.b) All Vessel’s in the Vicinity ( 15NM radius approx.) had interference.c) 1106LT, signal regained. HDOP within limits. GPS signal satisfactory. Matter resolved.d) During this incident vessel is in south China sea and there were three unidentified vessels can’t be seen on AIS.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202464902/07/2024AutomobileUSER: Tried two different systems. Apple iphone (waze app, and google maps) as well as the integrated gps in my truck (ford f150). Neither system was tracking for approximately 1.5hrs. Was traveling east from Columbus OH to Pittsburgh PA on I70. At times system showed i was traveling west on that road, and or running parallel off the road 30yds….. Applications kept trying to correct course infinitely as the system wasn’t tracking.Rebooted both systems, nothing helped. System returned to functioning after about 1.5hrs of in correct operation (and i had travelled about 90miles east of Columbus OH).
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202464802/05/2024AutomobileUSER: As soon as I start the google maps it take the position and immediately after I got the message GPS signal lost. The only way to get the position again was to close the app and start from the beginning. I got the position and after few seconds the message GPS signal lost. This never stops for about 40 minutes. Then I reach my destination and I have not checked anymore the GPS signal. Thanks.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202464702/03/2024OtherUSER: This anomaly has been ongoing since approximately January 3, 2024, and occurs at and around the junction listed at the above lat and long. When I approached that junction, all of the active GPS devices started to shift off in the incorrect direction. Normally, around 30-40 degrees of deflection from the route of travel. This deflection generally continues to occur for approximately 3-5 miles after the anomaly begins, and then the GPS corrects back to the route of travel. This anomaly tends to occur between around 1100z to sunset (around 2300z). My Jeep Grand Cherokee's integrated GPS has a satellite details page, and all of the satellites have high signal strength and an ample number of satellites. Due to the consistency of the interference and its start and stop timing, my initial assumption was some sort of ground-based interference either as unintentionally generatorated RFI or intentional interference. I will happily provide screenshots from both my iPhone and photos of the details page from my car if requested.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202464601/30/2024CommunicationsUSER: This is a broadcast and microwave relay site. The interference is happening on or near the site. I used my Anritsu spectrum analyzer with a passive directional antenna and saw interference in and around the GPS L1 frequency band but could not find its source. It has been happening for over two months now.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202464401/27/2024MarineUSER: As understood, there is a ongoing GPS disruption/ jamming in ji*zan area
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202464001/23/2024MarineUSER: Intermittent disruptions. "Loss of position/Alarm window 212 " message appeared during disruptions.Appeared from 13:06 UTC to 14:40 UTC
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference01/24/202464201/23/2024MarineUSER: Vessel underway from Jubail to Fujairah. Vessel experienced loss of GPS two times in less than 24 hours while in transit in Persian Gulf. Position of first occurrence started on 23 Jan 2024 23:00LT(+3UTC) in position 27 08.8N 049 50.4 E and ended at 2323LT (+3UTC) in position 27 12.1N 049 54.1E. Second occurrence happened on 24 Jan 2024 at 0523LT (+3UTC) in position 27 10.8N 051 16.2E and ended at 0630LT(+3UTC) in position 27 08.8N 051 31.3E
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202464301/23/2024MarineUSER: -At 23/01/2024 15:20:00LMT an alarm sounded on No2 GPS stating (no position fixing) and a message appeared stating that it was unsafe for navigation. During the time of first alarm 12 satellites were observed to be tracked. After 30 minutes and when the gps signal totally lost, observed that 0 satellites were tracked. No1 GPS was still properly working with no alarms and safe navigation indication was enabled. After 30 to 40 minutes the same alarm of no position fixing sounded also on No1 GPS and the position from ECDIS monitor appeared to be on land 50 - 60nm off original psn. The issue commenced at 23/01/2024 15:20:00LMT and lasted until 24/01/2024 00:00:00LMT. Positioning from LAT: 16.900 N & LONG: 040.900 E until LAT: 18.700 N & LONG: 040.3 E. According to the above, GPS loss signal is described as spoofing, both equipment was still on but unable to receive any signal from satellites.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202463801/22/2024MarineUSER: Reporting loss of GPS at ji*zan DW channel entrance.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202464101/22/2024ResearchUSER: White Sands Missile Range conducts testing several times during the year. These tests usually disrupt our GNSS receivers reducing the SNRs sometimes small amounts and sometimes to the point where the receivers lose lock and stay that way for hours. Up until last year these test periods were listed on the Approved GPS Testing Schedule. I believe that schedule was only updated twice last year. The current one is still for 2023-06-30. Signal degradation was also seen in August, October and December of 2023. This problem was for just a very short amount of time at approximately 0703UT. Plots of the interference can be seen at www.passcal.nmt.edu/~bob/gpsmon/7gmwsmr.html, though this one is pretty short/small. Another report will be made for 2024-01-23 on the 24th (after daily results are plotted).
NAVCEN: Thank you for bringing this to our attention, the GPS testing page has been updated.GPS Testing01/24/202463601/19/2024MarineUSER: Vessel is fitted with 2 GPS equipment (FURUNO GP-150). Both GPS appear to be jammed in ji*zan area (Saudi Arabia) due to proximity of Yemen border. At time, the location is showed on land in Yemen, somewhere near the border between Yemen and Saudi Arabia.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202464501/18/2024MarineUSER: When vessel was approaching the port of Haifa, Israel disruptions of both GPS/GNSS signal occured. At first it was intermitent and as vessel progressed sailing towards pilot station both GPS/GNSS signals were completely lost. At times, during anchorage stay, the vessel experienced spoofing as GPS position observed inland of >50nm from vessel's actual position. When the vessel heave up anchor and commenced proceeding to pilot station it was observed that the GPS/GNSS receiver was working properly for few minutes and again signal disruption occured to all GPS/GNSSreceivers until the vessel berth and commence cargo operation. At departure the vessel had no signal coming from both GPS/GNSS until about >20 nm from Haifa, Israel.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/26/202463501/17/2024NoneUSER: Hi, there has been temporary RAIM outages for Lord Lowe Island in AUSTRALIA. See RAIM NOTAM below. However, the problem is the outages predicted for TSO-C146A for FAULT DETECTION AND EXCLUSION are actually also applicable to TSO-C129A for FAULT DETECTION.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found possible to have impacted GPS performance due to minor geomagnetic storming. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information02/12/202463401/14/2024CommunicationsUSER: This has been an ongoing issue for the last month. All nav systems in Ocean City, NJ on iPhone and vehicles lose GPS signal for long periods of time and are off by miles. Essentially the problem comes and goes and is solved by driving North for about 8 miles on the Garden State Parkway. Because it’s happening seemingly randomly it’s hard to pinpoint but it’s been happening almost daily for the last month. Again, this isn’t an equipment issue because I’ve tried three different systems and it also isn’t consistent but when it’s not working- none of the devices can find a correct signal.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference02/12/202463712/18/2023Law EnforcementUSER: Hello, I am at Telecommunications Specialist with Drug Enforcement Administration in Seattle, WA. I am seeking any reports of GPS (active/LNA) antenna failure around 12/18/2023. Several agency radios w/ GPS receivers no longer receive GPS signals. I suspect it may be related to the X2.87 solar flare on 12/14/2023 so I'm looking to confirm other incidents. Any ideas/help would be appreciated.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found possible to have impacted GPS performance due to X2.8 solar flare. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information02/12/202463112/16/2023NoneM/V NORSEINE , IMO No. 9596052 experienced GPS signal failure at both GPS units simultaneously. The event happened during transiting Bab El Mandab Strait.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/20/202362912/14/2023AutomobileUSER: Apple iPhone also 2024 Audi Vehicle gps was also wrong Strange that two different devices were so far off.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information12/20/202363012/14/2023OtherUSER: I am stationed two to three times a month in the same village, in Malaysia, even though I live in France. This is happening on two phones, one of which has been reset. I can send you my Google routes. I tried to use the GPS-test application to check if I was a victim of GPS spoofing. I was then able to see Russian satellite number 15 (C/NO 22.4 elev 45 azimuth 191) and American satellite number 27 (C/NO 16.5 elev 43 azimuth 289) on 12/14/2023 at 10:38 p.m. local time. When I returned to normal a few minutes later, I no longer saw these satellites. Can you help me define the problem? Am I a victim of GPS spoofing locally?
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information12/20/202362712/11/2023OtherUSER: I'm a home user wanted to let you know on my Samsung galaxy watch 4 and Samsung galaxy a13 5g android cell phone when gps or location turn on I don't get any lock on any satellite from gps just fails also I'm in desplaines il any wear near desplaines il or in town this happen use it to get place but failing since can't get a lock on gps sat I know this dew to used a testing app on android it told on 0 sat lock
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User Equipment12/13/202362412/09/2023AutomobileUSER: Noted navigation anomalies while using iPhone and Waze app. GPS position several hundred feet off. iPhone and app reset several times. Cross checked results with a handheld Garmin eTrex. GPS satellite page showed good almanac and sats in view, but intermittent/poor lock. “Accuracy” indicated ~200ft. Anomalies started around 10:30 local time, continued till at least 10:45 local time and was ongoing when I turned equipment off. Note: this was in an automobile. I use GPS daily for traffic/commute information. During daily use, I have no problem with GPS reception in this automobile. I understand that iPhone/apps may be suspect, but the cross check with Garmin handheld indicates a true anomaly.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/13/202362112/03/2023MarineUSER: Loss of position/Alarm window 212 " message appeared during the time of disruption. Its came back to normal once acknowledged.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/06/202362012/01/2023OtherUSER: All mining vehicles report position errors accross a number of different mine sites. area around 500kms. Scintillation seems very high on Trimble planning tool online
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found possible/likely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Other12/06/202363312/01/2023New York CityCommunicationsUSER:Was driving and the GPS (google maps) was all over the place, for example it was telling us to make a local street turn while driving on a highway. It was directing us to go West when the destination was South. Both of our devices were producing similar incorrect results, both devices were of different models Samsung Galaxy Mobile phones both restarted to troubleshoot the GPS navigation issues. We were driving in NYC from Queens to Brooklyn and experienced this anomaly only that 1 night.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Address appears on google maps. User was sent data mapping information. Currently no additional information.Insufficient Information01/11/202461711/30/2023NoneUSER: USCG SECNY was notified of ship jamming incident on Carnival Cruise Line Cruise ship "Carnival Venezia" (November 30th, 2023) Pilot on Carnival Cruise Line Cruise ship "Carnival Venezia" reported jamming detected with Sandy Hook Pilot's Portal Piloting Unit (PPU) while transiting into New York City, NY. This jamming caused interference in ships real-time communications processes. This jamming was detected at least 2 times in locations, Ambrose Pilot Boarding Area and in Gravesend Bay, NYC. Sandy Hook Pilots bring SafePilot Software and CATXT V5 Antennas onboard. Trelleborg is the manufacturer.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/06/202361811/30/2023NoneUSER: USCG SECNY was notified of ship jamming incident (November 30th, 2023) Pilot on Carnival Cruise Line Cruise ship "Carnival Venezia" reported jamming detected with Sandy Hook Pilot's Portal Piloting Unit (PPU) while transiting into New York City, NY. This jamming caused interference in ships real-time communications processes. This jamming was detected at least 2 times in locations - Ambrose Pilot Boarding Area and in Gravesend Bay, NYC. Sandy Hook Pilots bring SafePilot Software and CATXT V5 Antennas onboard. Trelleborg is the manufacturer.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/06/202361911/23/2023MarineUSER: GPS display was completely blank - no latitude and longitude presented. Restarted GPS receiver with unsuccessful result. GPS signal was recovered only after departure from Aqaba/Jordan on 25th November at 00:00 LT (LT=UTC+3) in position 28°59.4’N 034°46.1’E and once we moved out off Israel/Jordan territory.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/06/202362811/22/2023MarineUSER: USCG LANTAREA was notified by the Health, Safety, Security, Quality, and Environmental (HSSQE) Manager for Seabulk that the U.S. flagged M/V GREEN COVE (IMO 9181560) experienced suspected GPS spoofing while on inbound transit to Aqaba. The GPS information for the ship, the Captain’s GPS watch, and Polestar all show that the vessel is in Cario. HSSQE Seabulk Group will continue to monitor.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/20/202361511/16/2023AutomobileUSER: 3 separate devices (2 different models of iPhone and the onboard navigation of an Audi Q3) showed an incorrect location which was repeatedly sliding around a wide area (10's of miles) in random directions. All 3 devices were rebooted and user moved up to 1 mile and still experienced the errors. After a period of 30 minutes driving ~20 miles south the locations on all devices corrected and began to function normally.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. 11/27/202361411/06/2023MarineUSER: Number of satellites tracked on occurrence are unknown.Insufficient Information11/20/202361210/20/2023MarineUSER: VESSEL HAD ENTERED ISRAELI WATERS AND FROM 16' IN WE LOST ALL GPS INPUTS. NO SATELLITE WAS SPARED. IN CONSULTION WITH IDF IT MAY BE WEAPON RELATED Unknown Interference10/30/202361610/17/2023OtherUSER: Spacecraft locked onto an apparent spoofed GPS signal while transiting southern Russia, east of Ukraine. GPS jammed environment has previously been experienced, with number of GPS solutions dropping to 4 or fewer. most of the time, when the spacecraft leaves the jammed environment, the GPS signal returns. This event required Flight Operations Team intervention.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference11/27/202361010/09/2023AviationUSER: Hello. Several operators have reported GPS reception problems today over our territory. This is highly unusual. We are still investigating the issue. It concerns both helicopters and civilian jet aircraft.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/16/202360809/30/2023TransportationUSER: I was driving on 495 S from Bethesda MD to Fredericksburg VA using Waze for navigation. Waze began malfunctioning and thought I was on some random side roads a good bit off to the side of 495 & began continually re-routing. Force restarted Waze, problem persisted. Had my passenger try switching to Apple Maps & it had the same issue, thought we were off on the side like Waze did. Thought it might just be my phone then so tried engaging my cars built in nav system and displayed the current gps location in the same inaccurate position as Waze was. At that point suspected it was not something with my phone but likely a broader GPS issue given it was happening across devices. Did not think it would help, but for the sake of trying, I powered my phone completely off since it was connected via CarPlay just to verify there was no possible way that my phone was somehow interfering with my card nav system (tho I don’t know how that would even happen anyway). My passenger took a picture of the cars nav system & Waze being simultaneously incorrect in the same spot. The issue persisted from 495 S through getting on 95 S until we were about 10 miles north of Fredericksburg.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/09/202360909/30/2023MarineUSER: Noted multiple occasions of GPS short signal loss at ji*zan Tanker anchorage B It was started on 29 Sep 23 around 1600 LT/1300UTC and continued until 30 Sep 23. First only GPS No. 1 was affected, however on 30 Sep 23 at 1000 LT/0700UTC both GPS units have lost satellite signal (none of satellite visible). Every occasion lasted few minutes and then signal recovered. This happened frequently, at present all finished. Vessel anchored on 15th Sep and all previous days GPS was operated normally.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/09/202360709/27/2023NoneUSER: Ever since the tropical storm, the enter the GPS has been very, very intermittent. It's been off. It's been on. I can be on 64 and the GPS says no GPS signal and I use multiple devices including my vehicles. Keep saying the same thing so it's just not a single device. It's multiple devices reporting the same issue that this is signal or GPS concern and this is all 64 East and the zip code is 23185 Williamsburg. Virginia and it's been going on about 4 days now
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/02/202360609/24/2023AutomobileUSER: Intermittent, sudden, Gps drift made it appear as if we were several hundred feet North of Highway 58, moving, and icon appeared to be headed WNW instead of W, as Highway 58 is oriented. This was noticed 3 times, on our journey from Hinckley to Mojave.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/02/202360409/20/2023SurveyingUSER: Collecting data with WAAS enabled consistently worsened the GPS position accuracy. This was found over a period of 1.5 hours.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User Equipment09/25/202360209/10/2023CommunicationsUSER: We have 18 devices that utilize GPS to synchronize communications and all devices lost GPS signal at the same time. This has happened several times since 9/8/2023.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information09/11/202360309/10/2023AutomobileUSER: we were directed to a residence on grand ave . we wanted to go to the methodist hospital in des moines. the residence has experience so many people being misdrected that he had a permanent sign posted to go 4 miles north of his residence to find the methodist hospital.
NAVCEN: Provided user information to update mapping information.Mapping Issue09/18/202360009/07/2023MarineUSER: Vessel has been at anchor for four days in the same Kuwait "Waiting Area" anchorage. The GPS lost signal starting around 0615Z and then was intermittently obtaining a signal. Vessel remains at anchor and has power cycled the GPS unit several times throughout the day.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference09/11/202359808/24/2023CommunicationsUSER: General outage of NTP time sync during +- 16:00 and 17:00 24th August
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information08/28/202359008/06/2023MarineUSER: This is M/T Mutriba was approaching Suez and while approaching in Gulf Of Suez experiencing intermittently loss of GPS signal on both DGPS receivers, AIS and GPS Compass. Loosing of Signals are very frequent. Presently vessel is at Suez anchorage. Suez VTS was informed on same and they confirmed that there is GPS Signal issue in the region. Moreover as per them many vessel are facing the same issue. Vessel Shifted to inner anchorage and from past one hour GPS signals are good and getting good fix.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference08/07/202359407/19/2023OtherUSER: During static operation with clear view of the sky two separate units experienced a week number decrease by 1 shortly followed by a complete loss of lock for 20 seconds.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference08/14/202358206/15/2023JAZIRAT JABAL ZUQARMarineUSER: GPS Disruption Commenced at 1555 LT (1255 UTC) in Position 14-05.7 N 042-14.4 E, Vessel was heading on a True Course of 151 Degrees and Speed 12.7 kts. The Disruption occurred 4 times with interval of 3 to 5 minutes.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User encouraged to report the issue to the nearest communication authority.Unknown Interference06/22/202357906/02/2023Sparta, GeorgiaAutomobileUSER: On three separate devices, GPS was either “not available” or showing a drastically incorrect location on the map. The issue has been consistent for more than 30 minutes for each device.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information06/22/202357805/25/2023Annapolis, MDOtherUSER: The tracking system on my boat sent an alert at 1:55 AM EDT (5:55 UTC) that showed a movement of approximately 130m for about 10 minutes before returning to the original location.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information06/22/202357705/22/2023Perris, CACommunicationsUSER: Google pin wanders off beyond GPS margin of error, and snaps to exact wrong locations. It shows my pin in my neighbors house, and proceeds to jump to other neighbors houses in a clockwise like fashion. It jumps across the street in the backyard of a house a few houses down, and jumps back and forth doing this strange routine without ever fully zeroing out after gaining satellite signal from over 3 satellites. Please let me know what this may be, because the gps on my computer holds true and doesn't wander using a ublox gps on windows10.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information. Other equipment operating properly. Currently no additional information. User Equipment06/22/202357405/13/2023Constanta, RomaniaTimingUSER: We have often GPS outages, almost every night in this city, on all cell sites in this city, but tonight the outage/interference is reaching as far as 45.452324 28.034280, aprox. 160km from the sea, which seems to be the source of masking/interference or whatever is happening.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User encouraged to report the issue to the nearest communication authority.Unknown Interference06/21/202357205/06/2023Montgomery, ALAutomobileUser: Gps position has been consistently ~300m south of actual position for the past few days. User: The location in Google maps and other apps moves around even though I am not moving.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information. Currently no additional information. Insufficient Information05/10/202357105/05/2023Norfolk Nebraska CommunicationsUser: In the area of Norfolk Nebraska the GPS for the last week or so has my position south and west of my actual location and it is impossible to navigate in the city at all. My GPS works fine everywhere else I have been and is off the same every time I go there. My phone does try and locate GPS alot in that area and once every few minutes it will correct itself and then go right back to being off track.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information. Currently no additional information. Insufficient Information05/10/202357004/23/2023BRISBANE AIRPORTAviationUser: Outage appeared to have started on 23 APR 2023 0030UTC and resolved around 23 APR 2023 2330UTC. Weather conditions were fine most of the time. Some moderate rain cloud cover/overcast on the following day before it resolved itself. Our GPS RAIM system has dual Trimble dome antennas mounted on the roof of our Brisbane ATS Centre facility with redundant paths and CTI SV12 receivers and servers rack-mounted within our Main Equipment Room.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User encouraged to report the issue to the nearest communication authority.Unknown Interference05/10/202356904/17/2023Youngstown, OHOtherUser: This issue is happening across several vehicles where the GPS has stopped. GPS is working, but not locking in on SAT's. Have verified drivers for the software.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information and requested additional information with no response. Currently no additional information. Insufficient Information05/10/202356703/31/2023BerlinAutomobileUser: When using build-navigation (in Audi A5 2020) and iPhone 13 mini with Google Maps, Waze, and build-in Maps applications, my location was off by ~100m at first (around 2:30 pm, local time GMT +1). Eventually, it resulted in a ~3km offset towards the southeast. I can provide a picture of the current vs. actual location, a video of how it looked on navigation applications, and Google Maps trace if needed.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Possible unknown interference. User was also sent data mapping information. Currently no additional information. Unknown Interference05/10/202356203/12/2023KAVKAZ, RUSSIAMarineUser: WHILE VESSEL AT KAVAKAZ OPL ANCHORAGE, RUSSIA. VESSEL’S BOTH GPS UNITS LOST POSITION MANY TIMES AND IT IS KEEP GOING AND COMING. SOME TIME IT IS NOT COMING FOR HOURS. ALARM CODE -212 LOST POSITION.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2023-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/10/202356303/09/2023Bratislava, SlovakiaResearchUser: Everyday periodically - every 12 hours occurs the time window for 3-4 hours during which many GPS receivers are affected and report 0 satellites fixed = NO-FIX or generating bad timestamp for a while. This is probably caused by one of the satellites which is sending some incorrect data. When this satellite leave our area - everything works normally again. This problem is detected from 2023-03-09 and still happens every day twice time till now!
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User encouraged to report the issue to the nearest communication authority.Unknown Interference05/10/202355903/06/2023Indian Ocean, North of SoqotraMarineUser: All GPS units lost the signal for approx. 18 minutes.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2023-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.Unknown Interference05/10/202355803/01/2023South East Redmond, Redmond, WAOtherUser: Any given time. GPS is lost in the is area in different multiple smartphones.Also... compass shows wrong directions.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information. Currently no additional information. Mapping Issue05/10/202355702/09/2023MarineUsers: GPS units Leica MXMarine MX-420 and SIMRAD MX-610 loosing signal at 12:15LT( UTC -3) every day (this is happening in Santos,Brazil area and subject to calls can be different time but each call usually issue will be at same time) and restoring in about 1-2 minutes. -On 08/02/2023 at about 23:30LT (UTC – 3) it was suspected that GPS signal was intercepted/jammed. GPS unit indicated high accuracy and no alarms but same time GPS position had been changing 300 with speed 86kn during anchor stay.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User encouraged to report the issue to the nearest communication authority.Unknown Interference05/10/202355502/08/2023ji*zAN PORTMarineUSER: The disruption was intermittent from 08:50 LT to 10:37 LT. A total of 8 times.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference02/15/202355302/06/2023Caofeidian / ChinaMarineUSER: GPS alarm 212: Loss of Position

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference02/15/202355402/06/2023WURTSBORO NYOtherUSER: All 3 devices show a lost of GPS signal from 12:39 to 12:57 PM, was at an elevation of 1300 ft clear view of sky

NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information02/15/202354901/03/2023Oklahoma City to San Antonio and SW TexasAviationUSER: Interference in this area was displayed on the website GPSJam.org for the period 3 January 2023 to 6 January 2023. No interference was displayed for 7 January.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Was determined that there was no known interference to GPS users.

Insufficient Information02/15/202354612/10/2022Lehigh AcresLaw EnforcementUSER: On 12/10/2022 we experienced degradation of GPS signal quality reported by multiple devices across the US covering multiple time zones (Eastern, Central, Western). Main areas/States affected were FL, West Virginia, Arizona, Texas, New Mexico. The occurrence began around 7:30AM Eastern and ended around 7PM Eastern. This displayed itself as unusually consistent drift or multipath behavior where there is a lot of point scatter also loss of GPS signal altogether.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information02/15/202354412/09/2022Strait of HormuzMarineUser: GPS signal appears to be jammed in Strait of Hormuz. At the time of reporting, other vessels navigating in the area were reporting the same issue with GPS.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference01/18/202354312/08/2022Strait of HormuzTransportationUser: Vessel underway, approaching to strait of Hormuz, outbound. Signal lost on both GPS for 1hr 32min.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference01/18/202354111/30/2022Arabian / Persian Gulf, Strait of HormuzMarineUSER: The GPS signal lost occurred on November 30th, 2022 between 0212 UTC and 0324 UTC while the vessel was on approach to the Strait of Hormuz, within the Persian Gulf waters (the vessel's position: 26 17N / 055 56E to position: 26 29N / 056 15E). The similar issues with the GPS disruption were being reported by other merchant vessels in the vicinity of the position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/06/202254711/27/2022Suape Port, BrazilMarineUSER: On 27 November 2022, at approximately 0000Z, Experienced loss of signal on their GPS Navigation system while transiting through rainy weather off the coast of Brazil. Ship's technician inspected the antennas and found them to be in good standing. Signal restored once clear of rainy weather. Issue occurred once more upon leaving Panama, rainy weather effected GPS signal, but signal returned after weather had cleared. Company provided a technician to inspect issue upon vessel's arrival in New York.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference02/15/202353711/18/2022Woodbridge, VAAutomobileUSER: Location data showed a 1/4 mile offset from actual position across 3 map applications on my phone and the same offset was shown on my vehicles factory navigation map. It occurred for roughly 25min then corrected itself.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information12/06/202254011/18/2022Mersin, TurkeyTransportationUSER: While vessel arriving Anchorage Mersin, Turkey ( EAST MEDITTERANEAN ) Both GPS 1 & 2 Lost its signal for about 12 minutes. Even after arrival notice that we are losing the GPS signal about 10 times a day for up to 15 mins. All navigational equipment got affected during signal lose.Vessel informed VTS in the area, They advised to navigate with caution. All vessel in the vicinity were also experiencing with the same issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/06/202253611/17/2022San Francisco, CALaw EnforcementUSER: Been experiencing GPS issues putting 5 miles and not acting like a glitch but with a reception of interference from other sources. USED FLIR and noticed non thermal anomaly being directed from the A band from 45NE.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information12/06/202253511/14/2022Elon, NCOtherUSER: Our drivers for Paramount Logistics consistently have outages in the Graham/Burlington/Elon College area.As far as we can tell it is near completely random what is causing it- we are unsure what the issue is but it makes deliveries near impossible for some drivers as they need to use Scanner device as their navigation tool. Without this, they are unable to deliver or even scan in packages when they arrive, leading to a few issues. The scanners will lose signal, some restarting themselves due to lack of signal and others completely shutting off.

NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information. Recommended that there may be a reception issue in the area.

Insufficient Information12/06/202253411/08/2022Township, NJAutomobileUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information12/06/202253310/25/2022 California on I15AutomobileUSER: For a period of about 30 minutes, I experienced my reported location moving in a circular path around my actual location. I had two GPS units performing navigation at the time - both units showed the same deviation in position. I rebooted the phone during the incident and it did not change the behavior. After about 30 minutes, performance of both systems returned to normal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports or additional information from inter-agency partners or users.

Insufficient Information12/06/202253010/16/2022IndependenceAutomobileUSER: My mapping services are constantly searching for GPS in the Kansas City area. The Uber app and Google Maps cannot be used with any accuracy because of the GPS disruption.

NAVCEN sent data mapping information.

Mapping Issue10/25/202252810/06/2022Dallas, TX by Southern Methodist UniversityOtherUSER: For several years now, on and off throughout the week, the area in an approximately 1 mile radius of the provided coordinates experiences GPS disruptions, especially during the afternoon. When these disruptions occur, my phone (two different models) and in-car unit are unable to locate where I am, with the application constantly changing my location on the map, or incorrectly identifying where I am. However, as soon as I exit the problem radius, all issues stop and my mapping applications are able to locate me again. This occurs whether I am using my cell phone independently, or using my car unit in my car has its own GPS antenna which is mounted at the top of my windshield)

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information10/25/202260509/25/2022MarineUSER: Vessel STONINGTON EAGLE Reported loss of GPS Signal on all receivers at 15:00 UTC SEPT 25 on approach to Suez canal
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference10/02/202352709/17/2022Navy Yard, Washington DCNoneUSER: Our car navigation system and our mobile phone's GPS (Multiple navigation apps), both mine and my wife's, all indicated loss of GPS signal intermittently over the course of 50 miles from Washington DC I-295 through Harford County I-95.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information10/25/202252509/10/2022ChicagoAutomobileUSER: Both my standalone gps and phone gps report no signal in a usually strong area.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. No response for additional information.

Insufficient Information10/25/202252409/07/2022I-20 near Columbia, SCAutomobileUSER: Several times, most recently yesterday, when traveling on I-20 in Columbia, SC in car nav system stops working- screen goes blank, then tries to reset. Map will reappear, but without street names or landmarks, then resets again. This continues until east or west of Columbia, at which point nav system will return to normal operation.

NAVCEN sent data mapping information.

Mapping Issue09/13/202252109/01/2022Mesaieed Main Ship ChannelMarineUSER: At 1651 while transiting Mesaieed Main Ship Channel the No.2 GPS began showing erratic speed indications (28Knots vs 11.5KTS actual) then the receiver lost its fix. We switched to No.1 GPS. At 1653, No.1 GPS lost its fix. Both GPS units remained out from 1653-1659 (no speed/position data). At 1659 No.1 receiver acquired a fix. At 1701 the No.2 GPS got its fix back. Both screens displayed "NO FIX" during this time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/13/202252309/01/2022Porter RanchAutomobileUSER: GPS is positioning vehicle 200-300 feet east or west of actual location in the Los Angeles area.

NAVCEN sent data mapping information.

Mapping Issue09/13/202252208/31/2022Caofeidian anchorage / Bohai Sea – ChinaMarineUSER: 31.Aug.2022 / 1327 - 1333 UTC. GPS SHOWS VESSEL'S SPEED BETWEEN 0 - 95 kts JUMPING UP AND DOWN. GPS POSITION INFO RAPIDLY CHANGING AND SHOWN IN RED COLOR.2 TYPE OF ALARMS ARE RECEIVED: 1. ALARM NO 212 "LOSS OF POSITION" 2. ALARM NO 210 "HDOP EXCEEDED" 09.01.2022 / 1710 - 1720 UTC: NO ALARM INDICATION BUT POSITION IS JUMPING ABT 0.08NM

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/25/202257508/23/2022Cordova, AKSurveyingUSER: Conducted 9 hour static observation of tidal benchmark "945 4050 TIDAL 13" as part of the annual survey. The observation began at 8/23/2022 16:40 UTC and the GPS data appears normal until about 8/23/2022 19:00 UTC, at which point the signal was severely degraded until about 8/23/2022 21:30 UTC. The signal was again degraded to a lesser extent from 8/23/2022 22:15 UTC to about 8/24/2022 00:10 UTC. The resulting GPS position solution did not meet the minimum accuracy specifications for the annual tidal benchmark survey. A repeated survey conducted on 8/27/2022 did not show any issues and easily met the minimum accuracy specifications.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. No additional information. Insufficient Information06/22/202351908/18/2022Cartersville GeorgiaTransportationUSER: Tractor trailers on coming in a residential neighborhood.

NAVCEN sent data mapping information to report unauthorized vehicle traffic.

Mapping Issue08/23/202259508/18/2022NoneUSER: Gps isn't working appropriately and hasn't been for a while (fix it)! Seems to be THE difference between being in town (racing, etc) "or" not!
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information08/21/202351808/17/2022KAMSAR, GUINEA, WEST AFRICAMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/23/202252008/17/2022Panama City, PanamaAviationUSER: During departure from the Tocumen International Airport (MPTO), climbing through approximately 400 feet AGL, the aircraft lost all GPS guidance. GPS signal was normal on the ground. It was not lost until airborne. GPS guidance on iPad's was still available. It only affected the aircraft system. The pilot returned to base and the GPS unit was replaced. On departure, it occurred again. The pilot returned to base and shifted to a different aircraft. On departure it occurred again. Speaking with the avionics shop, this issue was affecting all aircraft in the area, including airline traffic. The loss of signal seems to occur within a radius of approximately 40nm, centered somewhere within Panama City or the canal zone. This occurrence first took place Wednesday, August 17, and is ongoing.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. Inter-agency partners confirmed known GPS interference in the area.

Unknown Interference09/13/202251708/15/2022Santa Clara, California. West of Bracher ParkTransportationUSER: I go buy a specific block in my neighborhood where my GPS tends to get disrupted or blocked. I have screenshots and maps of locations of the area where GPS is being blocked by something. It has been this way for a few months. Both my GPS watch and a GPS Testing app on my phone report issues when entering the area listed above. On the app, I had 38 satellites in use connected and it dropped to 12 in the dead zone. I suspect something in the area is disrupting GPS tracking as it's an open neighborhood next to a park.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. No response to request for additional information.

Insufficient Information10/25/202259608/08/2022OtherUSER: Multiple media reports claim GPS outages at the exact time fires were burning and people were trying to locate alternate evac routs.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Other08/21/202359208/05/2022MarineUSER: 2200LT (1900UTC)/ 05th August 2023 Vessel anchored W9 anchorage Adabiya City (Adabiya Port), Egypt. The vessel's GPS ringing alarm due to EPFS Error (Emergency Position Fixing System Error). The Suez pilot informed 05th to 06th August, the Suez area GPS jammed and was interrupted by unknown causes. Vessel does not use GPS position and then alongside at Adabiya port (1406LT/1106UTC / 06th August). At almost the same time vessel GPS was back to normal condition.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference08/07/202351508/02/2022Cumberland GapAutomobileUSER: Our car navigation system and our mobile phone's GPS all indicated loss of GPS signal intermittently over the course of 10 miles.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information09/13/202251407/30/2022Straits of HormuzMarineUSER: Vessel experienced GPS outage while transiting Hormuz Strait West bound .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/23/202251207/22/2022Fontana, CA AutomobileUSER: Google maps and Garmin satellite reception are continuously being interrupted

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information08/23/202258807/21/2022MarineOn July 21st 2000, Lat 31-14.3N 032-20.9E, MT Badlands Trader, IMO #9700483, transited northbound out of the Suez Canal. Upon departing Suez Canal, a loss of satellite connection caused both GPS units to fail. The vessel was equipped with 2 JRC JRL-7880 GPS units. Each unit is connected to its own antenna and can support all bridge equipment.Both units struggled to regain a fix while moving at 10 kts. The satellite display on the GPS contained 1-3 satellites instead of the average of 10. GPS positions arrived once every 3-5 minutes.The vessel safely navigated the next 30 miles using radar and intermittent GPS fixes.Loss of GPS Affected:•AIS through the loss of Course Over Ground (COG) vector. •ECDIS placed in deduced reckoning (DR) mode to maintain cross track distance and enable safety frame.•Wheelhouse Alarm Panel (WAP) All-call activated.•Radars with date, time & GPS input.•Gyro compass Auto-Latitude input. The loss of signal at the mouth of the Suez Canal forced the Badlands Trader to proceed onwards. The bridge team worked together to escape the dense traffic. Upon emerging from traffic, priority shifted to diagnosing the source of GPS loss. While departing the Port Said Traffic Separation Scheme at 2200, 31-34.3N 032-11.7E, the Badlands Trader called the tanker Violando, IMO # 942985, on channel 16. Violando reported they had GPS problems as well. 5 other unnamed vessels joined in the radio call to confirm their GPS failures. By 0100 July 22nd, Lat 32-01.5N 031-35.6E, the crew optimized the GPS settings to latch onto the growing number of satellites. Both GPS units regained steady fixes. We attribute the loss of GPS to a local loss of signal. Maneuvering delayed the re-acquisition of signal until more satellites became available. Both GPS units continue to fix. The crew will perform position checks against radar ranges and bearings upon sight of land this evening.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference07/31/202358907/21/2022MarineUSER: On July 21st 2000, Lat 31-14.3N 032-20.9E, MT Badlands Trader, IMO #9700483, transited northbound out of the Suez Canal. Upon departing Suez Canal, a loss of satellite connection caused both GPS units to fail. The vessel was equipped with 2 JRC JRL-7880 GPS units. Each unit is connected to its own antenna and can support all bridge equipment.Both units struggled to regain a fix while moving at 10 kts. The satellite display on the GPS contained 1-3 satellites instead of the average of 10. GPS positions arrived once every 3-5 minutes.The vessel safely navigated the next 30 miles using radar and intermittent GPS fixes.Loss of GPS Affected:•AIS through the loss of Course Over Ground (COG) vector. •ECDIS placed in deduced reckoning (DR) mode to maintain cross track distance and enable safety frame.•Wheelhouse Alarm Panel (WAP) All-call activated.•Radars with date, time & GPS input.•Gyro compass Auto-Latitude input.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference07/31/202351107/18/2022CA-89 N from Tahoma to Truckee and then I-80 WAutomobileUSER: For most of the drive from Tahoma to Truckee to San Francisco, our position was being reported by the GPS as being roughly 200-500 feet away from our actual location which caused both nav system and Google maps directions to continually recalculate directions because it did not think we were on either CA-89 or I-80. While we were on I-80, the reports were generally south of our location although there were some occasions where it was reported north (generally it seemed having trouble determining our exact latitude). Occasionally, the GPS would briefly report our current actual location and then it would drift off after a few minutes. The disruption lasted from 9pm PDT when we left Tahoma to 1am PDT when we arrived in San Francisco. It was the first time in years of using GPS nav systems that I observed any errors. It was also very strange that this lasted for hours.

NAVCEN: No correlating reports from other users, sent data mapping information.

Mapping Issue08/23/202258707/17/2022MarineUSER: The unit worked fine in July 14 but would not work on July 17 and still won’t work today, July 18. I have several of these Sitex units and antennas and I’ve tried all of them but can’t get a signal/GPS reading.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. User Equipment07/24/202350807/03/2022Auburn, MATransportationUSER: All online mapping services were unavailable. Tried multiple websites and apps on several devices. Other vehicles in the vicinity had similar issues.

NAVCEN No correlating reports. Sent data mapping information.

Mapping Issue08/23/202250706/25/2022Crawfordsville, IowaCommunicationsUSER: The satellite radio does not work and the map location is off by a few hundred feet.

NAVCEN Recommend contacting service provider for satellite radio if it does not correct itself, no reports from other users.

Insufficient Information07/06/202250606/15/2022Mediterranean Sea ( North of Libya & south of Greece )MarineUSER: Both GPS no. 1 & no. 2 alarm keep coming, screen show's 'GPS LOSS OF POSITION' & GPS No. 1 screen show's ' AUG 17, 19 00:00 (U) WARNING RECTIFIED, GPS LOSS OF POSITION" , Vessel called other ship in vicinity and asked regarding the status of their GPS, same problem that they are facing with their GPS, GPS alarm keep coming for about 1hr, @ about 15 Jun 2330 UTC / 16 Jun 0130 LT, both GPS become stable.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/06/202250506/14/2022GuleiMarineUSER: "No Fix" displayed on screen

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/06/202251006/13/2022Abu Musa IslandMarineMerchant ship departed Das Island and was outbound Strait of Hormuz. Ship informs as they approached Dubai area they experienced loss of GPS signal. It took 4 hours before signal was back. Ship reports other ships informing on VF 16 channel that they too have lost GPS signal. Ship informs losing GPS signal in all systems and receivers (GPS, Sat C, Satellite Log, AIS). GPS signal would come back for a minute however it would show wrong location and back at Das Island. Ship informs total of 4 hours experienced without GPS. All GPS issues started 2 hours before passing ABU MUSA Island and 2 hours after passing ABU MUSA Island.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/23/202262206/12/2022TimingUSER: For several hours we observed intermittent position changes (as high as |0.0012|) to multiple stationary GPS receivers. We are wondering if there was a known issue in the area at this time and/or if any other users reported similar failures. Any help would be greatly appreciated.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/13/202368506/10/2022AgricultureUSER: As solar flares began to hit earth GPS guidance became inaccurate and would continually change the location of where machine was. Will the GPS service most likely stay inoperative until the planetary k-index levels decrease? GPS system also started disconnecting auto-steer automatically and showing a satellite reception error.
NAVCEN: Space weather was reviewed and found likely to have impacted GPS performance. NOAA Space Weather Prediction Center reporting Extreme (G5) Conditions observed 11 MAY 2024Other05/13/202466006/09/2022MarineUSER: Vessel was enroute to Aqaba, Jordan when GPS Jamming happened in Gulf of Aqaba.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Unknown Interference04/08/202467106/09/2022MarineUSER: Coast Guard Sector New Orleans received multiple reports of GPS anomalies from multiple vessels in the Lower Mississippi River around 0145 local time. See Narratives:At 0458 local on 05APR24, the SCC RCVD notification from the Panamanian flagged Bulk Carrier NAVI STAR reporting a GPS discrepancy on board the VSL. At 0145lcl on 05AP24, the GPS O/B the VSL was malfunctioning and going to multiple POSN regardless of the actual POSN it was in R/S also reported other VSLS within the same location, including the US Dredge GLENN EDWARDS, experiencing the same discrepancy.At 0145 local on 5APR24 SCC NOLA received notification from the pilot onboard the XIN AN NING, a Chinese Flagged Cargo ship loaded with grain, of an equipment failure IVO LMR MM 37. The pilot reported the GPS receivers and radar screen going out intermittently since approx. 0139 local.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/08/202467806/09/2022CommunicationsUSER: GPS communication interruption frequently around 7am local time (+3). In the early morning GPS are up and track up to 6 sats
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference04/22/202468406/09/2022AutomobileUSER: No Comments Submitted
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Insufficient Information05/13/202452606/09/2022NE Washington, DCOtherUSER: I was using the Phone for navigation in Google Maps. I was mid-route when the map suddenly showed my location as several hundred meters west of my true location. As I continued to drive, it appeared to get worse. I reset the device but it did not correct the problem. I checked my location in an alternate mapping program and it continued to display the wrong location. My phone’s software is up to date. This has never happened before. The problem appeared to resolve approximately 30 minutes later on its own, after I arrived at my destination. It’s unclear if my location was corrected because I was on wifi at my destination or if it’s because the gps issue resolved.

NAVCEN sent data mapping information.

Mapping Issue09/13/202252906/09/2022Elko, NVAutomobileUSER: Drove from Wells NV to Livermore CA. All three of my GPS units experienced major off-track (hundreds of feet horizontal) offset errors, and my GPS logger recorded +5000-ft to -2000-ft altitude errors. Speed was at times reported at HALF the actual speed. This was a MAJOR disruption recorded on three independent GPS units. The time and coords I report are for the greatest elevation error (reported me at 10000-ft altitude in Elko NV).

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information10/25/202253206/09/2022HoustonOtherUSER: Driving in the Houston area, my phone and vehicle are both reporting my location being miles from where I actually am.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports or additional information from inter-agency partners or users.

Insufficient Information12/06/202254206/09/2022San Francisco, CACommunicationsUSER: I was using the gps and my elevation has been not showing the elevation and has been affected by local interference. I contacted the FCC, the source of the anomaly was producing high levels of static when dosimeter had been brought into direct contact and moved irregularity.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information12/06/202254506/09/2022South of Hormuz Straits, North of Ras Al KhaymaMarineUser: Both Marine GPS units lost position and went blank basically with nothing showing in the Lat/Long fields.Rebooting the DGPS units showed it passing the Power On Self Test without error’s but they both still displayed a blank screen with an alarm of “No fix”. Our personal GNSS receiver still gave a GPS fix(satellite only), confirming the ship’s DGPS unit’s fix loss was not being caused due to satellite GPS signals but possibly due to jamming or scrambling of the differential signals. As both DGPS units were setup with “Auto” for most settings, this was changed to “GPS Only” mode to process only satellite signals & reject all SBAS & DGPS signals. The units were then re-initialized and this restored position fix data on them.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-010-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference01/18/202355206/09/2022Topeka, KSTransportationUSER: Flying a DJI M210 V2 with RTK we encountered total GPS loss (RTK was not being used) at around 200 ft. Over the span of a minute, the number of connected satellites dropped from 12 to zero and remained at zero until landing. Although RTK was not on, system displayed an RTK positioning error, and an orienteering error.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Currently no additional information.

Insufficient Information02/15/202356806/09/2022Port Townsend, WA, USAMarineUser: The primary and secondary GPS units on board appeared to lose connection with all satellites. Power cycling of the units did not solve the problem. Approximately 20min after the outage, the secondary unit maintained satellite connection and was able to provide position fixing, but the primary unit continued to experience a 'no fix' loss of position. After securing the vessel at the conclusion of the crossing, the secondary unit experienced a brief satellite connection interruption (<2min), in addition to a 'DOP' flashing on the screen. After approximately 1hr from the original connection loss, both units are now maintaining position fixes.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. .Insufficient Information05/10/202357306/09/2022CommunicationsUser: The location in Google maps and other apps moves around even though I am not moving.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. User was sent data mapping information. Currently no additional information, operates as expected when moving. Insufficient Information06/22/202358006/09/2022Elon, NCNoneUSER: FedEx driver states that my address is showing up at a camper behind a Church. This is an ongoing problem & has resulted in loss of approx $1,000+ in property over the last year. Alamance County Sheriff's Office has documented property damage to Church awning in an attempt to deliver to wrong address & has refused to do anything or provide guidance.
NAVCEN: There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users. Address appears on google maps. User was sent data mapping information. Currently no additional information. Insufficient Information06/22/202359906/09/2022AutomobileUSER: My maps will not show me in the correct location it just keeps jumping around a different locations. This issue has been ongoing for at least four days.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Mapping Issue09/04/202360106/09/2022AutomobileUSER: Location tracking is constantly 50-150 yards off, rendering route planning useless (constant recalculations).
NAVCEN: Provided user information for updating equipment software.User Equipment09/11/202361106/09/2022TransportationUSER: There is still a misdirection to my address. Have someone call me and I will explain. NAVCEN: User provided link for assistance in updating mapping software.Mapping Issue10/16/202361306/09/2022NoneUSER: We are just looking for assistance in updating our actual address on all GPS systems. We've updated with google maps but it still doesn't seem to be helping.
NAVCEN: Provided link to GPS.Gov mapping information.Mapping Issue11/13/202362306/09/2022OtherUSER:It’s been an on and off issue for about 2 years and is and obvious problem as it’s gotten worse. GPS location will jump erratically from the coordinates provided to New York New York, 40.701927, -73.923767 multiple times a minute after 7pm to 6am the next day everyday. I’m reporting this for multiple reasons. My fathers health is starting to decline in the event I call 911 I don’t want to end talking to a call center in New York. The millitary does fly directly over the coordinates provided which I know they use gps and them showing up in New York for a few minutes I could see being problematic. Lastly tinder the dating app is essentially useless aswell…..
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference12/13/202350906/08/2022Eastern PeruAviationUSER: On 6 occurrences over 90 minutes, GPS lost contact with all or all but 1 ( hard to tell if it was all and by the time I got to settings page, one had already reconnected ) Aircraft was tracking W and then NW between Puerto Esperanza and Pucallpa. On flight down in the morning, no anomalies notes. We have flown that route several times over the past month or more and had no interference issues. Same configurations, same frequencies, same aircraft. All reacquired within 30 seconds aprox. Hardware showed no signs of error and cabling/antenna checked out.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/25/202263906/08/2022MarineUSER: The vessel Overseas Sun Coast (IMO#: 9862944) is anchored off of Corpus Christi, TX. Our tracking software Navtor Navtracker correctly shows the vessel's position. The website vessel finder https://www.vesselfinder.com/ (which some of our customers use) shows the vessel in Oregon.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Mapping Issue01/26/202450105/28/2022ISKENDERUN/MERSIN BAYMarineUSER: On 28th May 2022 at 1940Z during trading in ISKENDERUN/MERSIN BAY was noticed that GPS signal totally lost from (GPS1 & GPS2) simultaneously and all the integrated equipments alarming due to position lost.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/06/202266305/27/2022SurveyingUSER: Topcon Surveying equipment is not working on our customers jobsite. Trimble Surveying base and rover is working. Old Topcon hardware will only track GPS and zero GLONASS. Newer Technology Topcon Hiper VR Rover and MCi4 controller (which can track all satellites) in the machine will immediately lose satellites in areas on half the site and in a certain direction towards buildings in the area. Tested all surrounding areas with rover driving around in my truck. I made a google earth map indicating satellites working and not working. Possibility the signal is coming from one of these buildings. Ball Aerospace, Brocade Communications Systems, EPK Solutions, CACI (previously LGS Innovations), Coalfire, or Trimble Inc. Areas that are working I am seeing 24 to 30 satellites as usual.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information.Unknown Interference04/08/202450005/26/2022tehranTimingUser: Time and date change via GPS signals.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Unknown Interference07/06/202249905/23/2022toledo, ohioCommunicationsUSER: 16000 H.D.P/8000 H.D.P./MISSING TIME/ -110 METERS ELEVATION/-300 METERS ELEVATION/ALL FROM MY HOME AT 2755 WORTH ST.OREGON,OHIO. AT 01-31-2020. AND OTHER DATES.AT PERRYSBURG MUNICIPAL COURT, PERRYSBURG OHIO.POSSIBLE UNDER GROUND COMMUNICATION CABLE.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Insufficient Information07/06/202257605/21/2022West Finley, PAOtherUSER: About nine riders were using portable GPS units to navigate a preset bicycle route. We rode between 10:00 AM and 3:00 PM. During the ride (at many points with a clear view if the sky) all of us were unable to get GPS fixes on our location or were getting located at points as far away as 6 miles from our actual location. The units were generally acting erratically during the majority of the ride. Because essentially all of our units were not operation properly at the same time and we were in an area where we have always had reliable GPS reception, we suspected maybe part of the satellite network was not operating correctly.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. .Insufficient Information06/22/202349605/18/2022Navra, Estonia.OtherUSER: Multiple Receivers. Overall low accuracy within 18km of border.Position accurate to only ~1km. Accuracy improves on the ground as distance from Narva increases.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners or users.

Unknown Interference07/06/202249705/18/2022Port Said - Egypt - Outside ChannelUser: Vessel has 2 DGPS/ and experienced GPS Jamming / Spoofing being done by local authorities in Egypt on regular basis on selected area basis location. Till the time the Canal pilot is there, there is no spoofing, once the pilot disembarks in the channel, the spoofing starts and continues till the time vessel is in the Egyptian waters. same is experienced when vessel is trying to join the Port Said Channel - from anchorage area till channel the spoofing is there, once the vessel enters the channel the GPS jamming is not there. There are no issues with the Make/Model of the GPS, the spoofing is there for all models and is common on most of the ship as discussed with other vessel at the time of joining the Channel - most ships had this issue. Also discussed with Suez pilot, and as per them, spoofing is done by Military.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/25/202249505/15/2022BelgradeUSER: After 35th Belgrade marathon many users reported their distance measured incorectly, with few hundred meters added to officialy certified length of half marathon and marathon tracks.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Insufficient Information05/25/202249405/13/2022Near Suez CanalMarineUSER: Interference occurred until entering Suez Canal, restored at position 31-27.8N / 031-02.1E

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/25/202249205/08/2022juaymah TerminalMarineUSER: Intermittent loss of signal on 3 x GPS units fitted to vessel.Disruption was sudden and as vessel entered Juaymah SBM buoy field. Previously no problems during approach and anchorage.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/25/202268305/06/2022AutomobileUSER: Several GPS users reporting intermittent inaccuracy issued in and around Rabun County Georgia. A variety of GPS devices experienced the same issue.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Unknown Interference05/13/202449105/05/2022Sandia Crest ALBUQUERQUECommunicationsUSER: issue is intermittent affecting the following locations.35.216528 -106.45241735.055278 -106.58166735.088389 -106.616556

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were authorized GPS tests in the area, listed on NAVCEN webpage. No correlating reports from interagency partners. No response when NAVCEN followed up with the reporting source to see if the issue was ongoing.

GPS Testing05/25/202249005/04/2022PerryvilleAutomobileGoogle Maps for address in Perryville, MD provides two locations one of which indicates an area that in not it is actual location. Marion Tapp Parkway in within the town limits.

NAVCEN sent data mapping information.

Mapping Issue05/25/202249305/01/2022Western north of iraqTimingUSER: The disruption happened everyday approximately at 13:00 GMT+3. The devices start losing synchronization.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/25/202258605/01/2022OtherUSER: Please refer to right reference: New apartment building with the electrical company of Legrand. New bright electrical company (Vehicle) parked inside apartment complex parking lot may be a disturbance with signal interference. During move in, plugged Apple computer inside of the outlet, computer completely locked out by the apartment complex (blue screen). About a month ago, while leaving the fourth floor on my way to work, a disturbance with the outside deck doors, a group of people alterring the new changes made to the doors, a female who appeared in distress, racing towards the corner I just came from. One of who appeared to be a worker joined the elevator with me. Since then my electrical has been of constant talk of what appears to be that women. Removing security files as low as human health (CDC) range and internet security files. Due to tinnitus the ears are currently sensitive to electrical, so upon the disruption with the removal of files a quick gasp, ring, or clog of the body and brain show reaction.a feeling of hate coming from this women. Though the issue is the electrical or the bulk internet account has been hacked along with the signals of vehicles. Network time servers may not be according to where it first was established. The problem is radio has went viral and no one wants to report the hearing of viral to accept the discrepancies of the error. Currently my phone account is linked to Verizon which may have also been compromised and the administrator account of the energy account compromised and being abused. The servers are connected to a gps system along with the utilipro time server which helps the time clock of almost all warehouse time clocks record work time. The company name ukg and utilipro. During the end of last year a job position at the airport was accepted. During training a report made of an immediate pull or tug at my inner left ear, as if someone tried to close it out. Reported to SIDA with no response and the email deleted from the servers. Years ago a memorandum came from the Presidents' house of a breech, the connections of the whitehouse.gov may be apart of a re-route and the re-route seems as if it could be a terrorist. My original nasa live now being forwarded to /nasalive. I need to ensure the database of my history is being routed correctly and the safety continues to remain.
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Other06/26/202348904/30/2022230 nm of the coast of LibyaMarineUSER: Vessel transiting eastbound through the Meditteranean Sea, 230 nm off the coast of Libya. GPS 1, GPS 2 & the GPS Compass lost the satellite signal. The Furuno GPS units showed "210 HDOP EXCEEDED.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/04/202248804/29/2022Tucson ArizonaOtherUser: Mr. Paul Miron (JNWC) has received a report of malicious GPS interference around Tucson, AZ near Davis Monthan-Tucson Air Force Base. Mr. Miron is collecting additional information from reporting source.

NAVCEN: After investigation it was determined where the source of interference was coming from. Once the interference was secured the GPS signal was fully operational.

Unintentional Interference07/06/202248704/18/2022Chocolate MountainOtherUSER: Unit acquired new in 2010, with no previous anomalies including during 24 hours of operation leading up to start time of problem. After 1.5 continuous hours recording a track (2 meter interval) with correct date/time, unit date/time changed from 2022-04-18 11:35:42 PST (GMT-08:00) to 1999-08-21 16:59:46. A few minutes later the date/time shifted again to 2002-09-02 11:38:24 PST (GMT-08:00) - correct time but incorrect date - and remained stable thereafter. Apparent week-number reversion in an older GPS unit, but the timing of the reversion seemed random and unexpected for the age of the unit. Signal interruptions and position anomalies up to 0.5 mile started at the same time as the first date/time change, and continued for several more minutes after date/time stabilized, despite being on an exposed ridgetop position with clear view of sky the entire time. Positioning stabilized at 2002-09-02 11:51:20 (true date 2022-04-18) with no further issues 24+ hours later, except for reverted week number (and after several power cycles).

NAVCEN: Provided reporting source information for manufacturer firmware update guidance to correct known issue.

User Equipment05/04/202248504/12/2022Mersin, Turkey, Anchorage #2MarineUSER: Vessel experienced both jamming, where the signal was lost, and spoofing, where the position was shown nearly 400nm to the north of actual position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/04/202248604/12/2022city of belmontCommunicationsUSER: loses gps signal in this area for the past few weeks, gps location is inaccurate by at least 1000+ft. occurs on multiple devices on multiple apps.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users.

Insufficient Information05/04/202248404/10/2022San Diego, CA (Fasihion Valley Mall areaAutomobileUSER: GPS on automobile was not working from about 1:30 pm to 1:45 pm Pacific time in San Diego, WI. It just kept resetting and resetting and could not find its place. Thus continued for at least 10-15 minutes. Not sure if related, but unable to place cell phone calls to my husband at same time. When we go into truck he remarked that GPS has been acting weird and I said I had tried to call, but my phone would not allow me to place calls for same time period around 1:35 pm in afternoon.

NAVCEN: Spoke to the reporting source and determined issue was with service provider. Car GPS was not working because it was using the phone through the auto application.

User Equipment05/04/202248203/30/2022ji*zAN CHANNEL , KSAMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/04/202248303/29/2022DunkirkAutomobileUSER: The GPS was confused; repeatedly gave inaccurate directions; would tell me to turn "right onto southern maryland boulevard, route 4, S" when that would put me into on-coming traffic. Did the same thing to turn left onto the same blvd going north; re-routed itself every few seconds; gave multiple directions, one right after the other. Would show the destination much farther away (EX: 6 hours and 11 minutes) when it reality it was about 20 minutes away. Repeatedly did this and kept changing the time to destination every few second. Verizon is my cell company. A friend traveling through Philadelphia yesterday (2.5 hours north of Dunkirk, MD) experienced the same thing. It was not just my phone or my area. Right now I keep having to re-enter the re-captcha code so your site is not working properly either.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users.

Insufficient Information05/04/202248103/17/2022abt 70 Nm off-Iskenderun , TurkeyMarineUSER: All Navigational and Communication Equipments out of order. Found out now from Agents AT Port Iskenderun that other ships are also having similar problems in the approach - due to Military Jamming.Even now there are interruptions from time to time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/04/202247802/27/2022Brussels, BelgiumOtherUSER:I was driving on the highway, GPS under the windshield, good reception, suddenly 0 sats, after 9 minutes again good reception. A detailed log (ubx format, nav pvt protocol, 10Hz) is available

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. User encouraged to report the issue to the nearest communication authority.

Insufficient Information04/05/202247702/22/2022Ashkelon, IsraelMarineUSER: Disruptions began immediately after arrival at anchorage in Ashkelon, Israel. Intermittent, in that they come and go, with periods of hours of no disruption followed periods of nearly continuous failure of signal reception.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2022-005-Various GPS Interference and AIS spoofing. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/04/202247602/21/2022I5 north through Portland, OROtherUSER: We were driving from just outside of Portland (OR) towards Seattle (WA) when GPS on the iPhone started misreporting the position. Rebooting device did not fix the issue. Switched to the GPS navigation in our 2021 Audi Q5, and it was also reporting an inaccurate position. Approximately 90-120 minutes later, the issue seemed to have resolved itself..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. No response to our request for additional information.

Insufficient Information04/05/202247402/04/2022Mersin TurkeyMarineUSER: all vessel GPS units stopped receiving a Signal and then the signal would default to 40N 40E. it has been off and on for 3hours now.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference02/09/202259102/04/2022OtherUSER: This is a bit of a unique situation. I believe someone has created a form of human receiver/antenna, possibly as an accidental university project that has been receiving unknown signals for the past years. These signals seem to be biotech based and hold a form of audio/video sensory. I believe they mimic that the static in the TV observing both white and black images at the time of interception. Whoever is doing it may have created a form of Faraday Cage and I fear that someone may have reported it as a threat to national security before I was aware of it. The timeline stems from 2020 - Present, with an incoming channel heard on a volume level as of Feb 2022
NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from inter-agency partners. No additional information. Other08/07/202347302/03/2022Dammam port KSAMarineUSER: At the time of disruption all GPS used on board was out of order for more than 4 hours.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference02/09/202247201/29/20223685 US-61, Blytheville, AR TransportationUSER: All three GPS devices stopped acquiring signal along route I-55 Northbound starting north of Jackson MS currently to Blytheville AR.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users.

Insufficient Information02/09/202247501/28/2022sikestonAutomobileUSER: in southeast Missouri it shows GPS fail but it worked when i drove to north east Arkansas and quit working again when i got back in Missouri.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. No response to our request for additional information.

Insufficient Information04/05/202247101/23/2022Fuquay VarinaOtherUSER: Mapping software is displaying an inaccurate location with up to a 130 ft error, variable. Typically the location with within a few feet. The error is not constant.

NAVCEN sent data mapping information.

Mapping Issue02/09/202247001/21/2022Aurora, ColoradoCommunicationsUSER: Approximately 1530 on 21 DEC 22 two of our base transceiver systems began to lose sync.The GPS receivers, control cabling, and surge protectors were replaced with no change to loss of sync. There are no other BTS affected other than three sites in Aurora, Colorado, There is also problems with the local public safety P25 simulcast systems which have lost GPS lock in this area.Spok provides critical encrypted health care communications at these facilities.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. After further investigation from inter-agency partners the source of interference was identified and secured.

Unintentional Interference02/09/202251601/10/2022Mitchell, SDAutomobileUSER: The date & time are not working on my auto radio. I do have GPS on my vehicle. It set it back to 2002 at 12:24. I called the dealer a few times and they said it has nothing to do with the dealership or auto. They said it is because it's being put on satellite and they are working at getting all the numbers set right. Corp. said that Aug. 12, 2022 is when it should be fixed. That date came and went and it's still not working. Can you please tell me when this all should be straightened out? If this is not the correct place I should be talking to, can you inform me of who I should be getting ahold of. Apparently they are switching from towers to satellite for the autos. Vehicles that were built before 2012 is what it affected. I would really appreciate some kind of a response. I know nothing about the date or time it occurred. I just noticed one day it was way off and couldn't reset it. Thank you.

NAVCEN sent information regarding GPS Rollover issues.

User Equipment09/13/202246712/26/2021500 miles from NE Coast of BrazilMarineUSER: On 26th Dec 2021 @ 2035 UTC, vessel noticed position fluctuating. Position verified using GPS2 on ship and found vessel position shifting by 2.5-3 cables automatically. And happened again on 27th Dec 2021 @ 1220 UTC with the same problem as yesterday. Presently vessel is using GPS with GNSS + SBAS option and was disabled the QZSS (Quasi-Zenith Satellite System).

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Unknown Interference02/09/202246612/22/2021Arcadia NSW AustraliaAutomobileUSER: Multiple devices showed incorrect location by approx 10km. Correctly showed movement through space.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. No response to our request for additional information.

Insufficient Information02/09/202246812/21/2021EmpireSurveyingUSER: During the weeks of December 21 and 28, we had the time to fix was very long when there was even slight skyview clutter accuracy and repeatability were considerably degraded compared to anything done in the last 12 months. The problem seems worst at 1030 am till about 1 pm. Also on another site miles away where fixed position time was less but accuracy and repeatability were also degraded. All receivers were rebooted several times and firmware updates were checked to be current. These problems were consistent and unexplainable. It was like stepping back in time to GPS equipment a decade ago. Radio links were strong time delay showed a second. Only in the wide open did the receivers function as expected as far as time to fix but repeatability was still degraded. Lock in cluttered or wooded areas that we have repeatedly performed this past year were impossible with and we tried two different receivers that have performed amazingly well in the last 12 months. I tried turning off each GNSS constellation to see if that made a difference and I tried turning off one SV at a time to see if that made a difference. Nothing seemed to work. I also contacted the equipment rep and we went over all settings and he suggested I check firmware which we did. This problem exists on two separate systems working in two different areas about 30 miles apart. We even traded equipment one day, and the problems still existed. I have checked the Nanu reports and one sat was unusable till the 27th but we had the same problems after that. I am hoping this clears up but I am concerned.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. No response to our request for additional information.

Insufficient Information02/09/202246512/16/2021Odessa/Midland, TexasAutomobileUSER: GPS system indicated no GPS signal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. No response to our request for additional information.

Insufficient Information02/09/202246412/10/2021Sao Sebastiao, BrazilMarineUSER: Position shifts to bearing 039 T , 0.47 Nautical miles off actual position..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Unknown Interference02/09/202246312/06/2021Palm Beach Gardens, Florida 33410OtherGPS just went down 2310 Local or 0410 UTC. Still down. Cause of GPS data loss could be cloud cover or atmospheric weather related or local interference. Moved GPS ground plane around but no further improvement. Usually I receive at least 8 GPS satellites. Backup USB GPS also is down for my PC as well.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. User indicated operation returned to normal after weather in the area cleared up.

Unknown Interference02/09/202245111/30/2021Highway 70 Hot Springs, ArOtherUSER: Sorry I can not provide details on what satellites were being tracked but as soon as I hit the coordinates above until I got to 34.49593400553349, -93.07499426473889 traveling through downtown I kept getting GPS signal "failed" messages and my location would shift in large jumps from half a mile to out of the city. I just wanted to give a heads up because KHOT Memorial Field Airport is parallel on that route. The route I took parallels RY 05/23.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Insufficient Information12/14/202145011/22/2021Ras Tanura Freighter anchorageMarineUSER: We are having problem GPS signal losing “EPFS”. on our vessel. She is running up and down north of RTE-7 anchorage/east of tanker anchorage Ras Tunara Freighter Anchorage KSA .Please check and advise.In same area we have checked many vessels with the same problem..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144711/14/2021LimassolMarineUSER: Full GNSS failure..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144611/07/2021Moni Anchorage close to Limassol, CyprusMarineUSER: Ship is anchored on Mony anchorage, Area around Limassol is known for occasional short GPS interference.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144511/06/2021Moni Anchorage close to Limassol, CyprusUser indicated an intermittent problem that was otherwise unspecified. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144411/05/2021LimassolMarineUSER: Complete position and speed failure of all gnss systems..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202146911/05/2021BrooklynOtherUSER: The maps wont go to any locations or give me directions.

NAVCEN sent data mapping inforamtion.

Mapping Issue02/09/202244211/04/2021Marsaxlokk. MaltaMarineUser indicated an intermittent problem that was otherwise unspecified. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144311/04/2021LimassolMarineUSER: Intermediate complete loss of position and increase of speed on all 3 GNSS - Issue is still on going..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202144111/01/2021Driving West into South Bend on I80AutomobileUSER: Mercedes Sprinter van says no GPS satellite. My iPhone position keeps wandering off the route and then instructs me to “proceed to the route” then occasionally comes back on track before wandering off again.

NAVCEN: Requested additional information, but there was no response.

Insufficient Information12/14/202146210/28/2021San Diego CA, Providence RI, Baton Rouge LATimingUSER: We have GPS clocks deployed across the US. Across many of our GPS clocks, I am seeing a marked decrease in satellites being tracked. I have graphs that will show this, from San Diego, Baton Rouge, and Providence, but I am unable to upload images via this form. Throughout the 2021 year, the tracking has decreased from an average of 8 satellites to 5, and then occasionally drop lower, and we get alarms when we drop below 3. There was an instance that started on 10/29 to 11/09 that shows a more pronounced drop during that time period. Is this a known issue or are there changes being implemented that can account for this change?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. The fluctuations in the satellites tracked appear to correlate with several released NANUs. The user will continue to monitor the status as NANUs are released.

Other02/09/202243610/25/2021Istanbul Strait / MarmaraMarineUSER: After dropping anchor at Istanbul anchorage, vessel reported both GPS outage. Same failure notification from many ships.Istanbul anchorage area there are some frequency interceptions for temporary..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202143710/22/2021Mapleton, NDSurveyingUSER: No satellites tracked on LED panel, and in the receiver utility. Static files from same time will process fine on OPUS. We have video of the behavior, and screen shots of the software screens. Manufacturer cannot explain the behavior, they should not act like that, especially all the receivers on the same job at the same time. This location is well south of the Northern Plains UAS test site. We have no idea what was in the air at the time of the incident.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. RS is working with manufacturer.

Insufficient Information12/14/202144010/20/2021I65, Alabama, mile marker 312-317CommunicationsUSER: I travel this section of interstate regularly. I would say 50% of the time I loose GPS in this stretch. It started about a month ago. A couple of weeks ago I saw workers working on the microwave towers in the area but those were installed a couple years ago with no issues so not sure what has changed in this short five mile section.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Insufficient Information12/14/202143410/18/2021North of Dubuque, Iowa in a 3nm radius of John Deere PlantAviationUSER: ADS-B locating problems.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. No response to our request for additional information.

Insufficient Information12/14/202143310/13/2021IstanbulMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202143210/12/2021PhoenixSurveyingUSER: The surveyor worked in the same area with GPS a week prior. This morning and afternoon the equipment could not receive NavStar satellites. A few GLONASS and Beidou satellites were seen.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. No response to request for additional information.

Insufficient Information12/14/202143110/11/2021LimassolMarineUSER:Speed and position draticaly changimng on all GNSS systems for an aprox duration of 5 mins. The interference in currently on going.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/19/202143010/08/2021LimassolMarineUSER: 2 of our 3 gnss systems have been intermitently using 0 satellites while tracking upto 22 GPS and glonass. the issue is still on going at this time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/19/202143810/07/2021IstanbulAviationUSER: I suddenly had an incorrect GPS signal, the home point was moved by several hundred kilometers. My drone then started moving in the opposite direction by itself. I am very confident that this was GPS spoofing by somebody trying to hack and take control of my device..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. There has been an increase in reports from users in this region.

Unknown Interference12/14/202142910/04/2021East of CyprusMarineUSER: During Disruption of GPS signal, as per GPS manual (Alarm 001 - 'NO FIX') appeared on GPS display and remain the whole time until GPS signal restored. GPS SIGNAL was restored satisfactory (after one hour)..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/19/202142810/01/2021Central PolandOtherUSEr: About halfway through the flight the number of satellites seen by the sonde started dropping. When it got to 6, it started giving timestamp errors. It then started sending out invalid GPS coordinates ie. coordinates in Belarus and altitude below sea level. This same thing happened with another meteosonde a few 100km south in Slovakia a couple of minutes later. After a few minutes of showing coordinates over Belarus and impossible altitude, the satellite count went up and normal coordinates resumed. I believe this is not a sonde malfunction since it happened with two different, independent sondes at the same time, hundreds of km apart. Other telemetry from the sondes were normal.More info here: https://github.com/dl9rdz/rdz_ttgo_sonde/discussions/204https://www.ebski.co/2021/10/01/r5020799/.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. Reporting source provided data plots that appear to be similar to other documented interference events occurring at or near airports in the region.

Unknown Interference10/19/202142709/25/2021Approaches to Tripoli, LebanonMarineUser: One of our company managed vessels, at the time of her approach to the port of Tripoli, Lebanon, experienced erratic behaviour on her various navigation equipment. Both the GPS installed onboard lost satellite signals. The gyro compass started showing an error of around 14 degrees. The vessel route on the ECDIS disappeared, the ECDIS started giving numerous alarms, and the tracked positions on ECDIS, as received from GPS feed, started jumping in all directions. All the equipment stabilized as soon as the vessel entered port limits, but similar erratic behaviour of the navigation equipment was observed during the vessel departure.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/19/202142509/24/2021Fortaleza Anchorage,BrazilMarineUSER: Vessel at Fortaleza Anchorage. Vessel noticed position fluctuating on the ECDIS. Position verified using GPS2 on ship and found vessel position shifting by 6-9 cables automatically. Presently vessel is using GPS 2 for navigation and out to all devices on the bridge.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users.

Unknown Interference10/19/202142609/22/2021FayettevilleOtherUser: For the past several days randomly anytime in downtown Fayetteville for some reason GPS just loses all signal I noticed it whenever my navigation both Google Maps and Waze and Uber and Lyft would seem to be confused as to where I was located exactly I also check the GPS location shown in my vehicle and for some reason it sometimes shows the correct coordinates but sometimes it just shows 1016.66667 , 1016.66667. I am not sure if the issue is corrected by distance or time but it seems more like it corrected by distance.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users.

Insufficient Information10/19/202142409/20/2021Limassol bayMarineUser: Both GPS position lost 11 satelites tracked non used. A common occurance here in Limassol bay.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-010-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference12/14/202142209/19/2021CyprusMarineUser: Since September 3rd we have had an increasing number of our ships reporting GPS position issues (unable to get a fix for several minutes or hours) in the area South of the Island of Cyprus in the Sea area. Are you aware of these issues ?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/29/202142009/09/2021LimassolMarineUser: Sateliets were tracked but not used,Deferential corr. was blocked.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/29/202141608/18/2021Bedford, UKOtherUser: Vertical data lost accuracy. Reported altitude changed from 20m ASL to -217m ASL and returned to 20m ASL over a period of 15 minutes. Horizontal location was unaffected.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

Unknown Interference09/29/202141508/15/2021At Sea sout Sicilia ItalyMarineUSER: Both of GPS receiver lost signal , its seem like external signal alteration, all Sat signal lost and come back for few second and lost again for 2 hours.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/29/202141408/12/2021NE of TUNISIAMarineUSER: Alarm Code - 212 Loss of position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/29/202141308/11/2021Port Said,EgyptMarineUSER: At 0300LT while getting underway from anchorage C-3, North Anchorage, Port Said, Egypt the vessel lost DGPS signal due to heavy Interference. We have two units on board. DGPS#2 regained signal after a couple of minutes while DGPS unit #1 had to be factory reset and rebooted several times before it was able to acquire satellites later in the day. Is this a common occurrence in the Suez Canal or was just an anomaly? The Suez canal Pilots said it is a common occurrence in the canal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/07/202140607/28/2021At seaMarineUSER: The vessel was sailing towards port said when we first encountered interference, we are now at am anchorage position out of Suez canal and the interference keeps occuring at intervals of about 10 minutes.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/29/202140907/28/2021Port Said EgyptMarineUSER: Vessel transiting Suez Canal Northbound. Bound for Algeciras Spain.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/07/202141207/21/2021ХарьковResearchUSER: Good afternoon, we have been observing anomalies for a long time, large scatter in the time scales of the satellites on receiver 1 according to the P code, receiver 2 also cannot correctly receive the p code. At the L5 frequency, the number of sessions was reduced to a few per day at the time of writing, at the L5 frequency during the week only 4 PRN 1,18,25,31 satellites were emitting. PRN 11 did not determine the azimuth and showed a large discrepancy between the satellite time and GPS time. please tell me what could be the problem.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The L2 signal in this region can be unreliable due to proximity to conflict zones. Both L5 and PRN 11 are currently set UNHEALTHY to users. Update: RS reported that the anomalies have stopped. They stated that the use of the signals is primarily for timing. The anomalies were observed on L1 and L2, however, L5 timing was unaffected.

Unknown Interference09/29/202140107/09/2021EgyptUser: Vessel was making way and lost GPS function.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/07/202140007/07/2021Port Said East Container TerminalMarineUser: The vessel was just finishing up transiting the suez canal when GPS interruption began. We would lose signal for about 5 minutes then it would come back for about 5 minutes. This lasted at least 1 to 2 hours as we exited the canal. We received reports from other vessels that they were having issues as well. The units on board are old models and scheduled to be upgraded during next docking period..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139707/02/2021NW corner of TunisiaMarineUser: Beginning with one unit only, GPS began to alarm "NO FIX" at 1100 at sporadic intervals. By 1300 both units indicated "NO FIX". Position has been briefly fixed, only to alarm again within 6 minutes or so..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139807/02/2021OFF PORT SAID, EgyptMarineUser: Both GPS reciever losing position fix intermittently..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139606/30/2021Suez CanalMarineUser: On receiver display: "Signal lost". Ships in vincinity confirmed similar signal loss..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139506/26/2021East of MaltaMarineUser: Vessel bound from Algeciras, Spain to Port Said, Egypt..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139306/22/2021At sea, 70NM East of MaltaMarineUser: Please be informed that early morning today at 0040LT/22 June GPS Pos. Lat 35-53.0N, Long. 016-01.2E, 70NM East of Malta, we experienced GPS interference. This resulted in Loss of Position on equipment. GPS interference was experienced from time to time after the first occurrence. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/19/202139206/14/2021Galina, AlaskaSurveyingUser: Checking grade for road construction.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but reporting source did not respond.

Insufficient Information07/19/202139006/07/2021Emporia, VACommunicationsUser: Traveling to and from Emporia Virginia and Norfolk Virginia said GPS SIGNAL was lost. Since Friday June 4th.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but reporting source did not respond.

Insufficient Information07/19/202138906/05/2021ItalyMarineUSER: All GPS RECEIVERS WENT INTO ALARM MODE WITH LOSS OF SIGNAL. OTHER VESSELS IN AREA ALSO REPORTED ISSUES.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference06/08/202138606/04/2021South of SicilyMarineUSER: Various other vessels in the area encountered the same condition.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference06/08/202138806/04/2021Off Sicilia, ItalyMarineUSER: The vessel has been experiencing an intermittent loss of GPS signal on both GPS units aboard. The Max time so far has been around 10 minutes of signal loss, and then it has come back. We have restarted the units and made a few course changes to see if things improve. Over the last hour, the GPS signal has been in and out. We have heard other vessels report similar issues with loss of position. I would estimate that we have lost signal for about 15 minutes during the last hour.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference06/08/202139906/01/2021Jonesboro, AR; Craighead Forest ParkOtherUSER: I’m wondering if someone has a GPS jammer or something else that interferes running in or around here; GPS locks go in and out on all equipment I’ve used in the area.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information09/07/202138505/25/2021Malta Channel, MedMarineUSER: All ships in the vicinity (60 nm reach of Malta Channel) lost all satellite signals at the same time. No signal received since around 23:20 LT on May 25th, ongoing. From 22:00 LT to 23:20 LT intermittent loss was experienced, and vessel also lost radar signal for around 2 minutes once.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference06/08/202138005/24/2021Riace, ItalyMarineUSER: No pos. gps.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202138305/24/2021Tacoma, WAAutomobileUSER: Moving car icon on screen often displayed location several hundred yards to the West of where we were actually causing Google maps to continually attempt reroute off of surface streets when we were on main highways between Tacoma and north up Kitsap peninsula to Narrow stone Island. Two devices displayed same anomaly over several hours.

NAVCEN: Sent reporting source mapping updating information.

Mapping Issue06/08/202138205/22/2021East Mediterranean SeaMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202137905/17/2021DallasAutomobileGoogle maps down. Possible widespread gps problems.

NAVCEN: Provided reporting source the website information to GPS.gov for mapping issues.

Mapping Issue05/27/202137805/14/2021Lompoc, CAUSER: Was going to the beach, could not acquire GPS signal.My phone is brand new, so problem lies within the satellite.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/27/202137705/13/2021Marthas VinyardSurveyingUSER: Lost GPS on 4 vessels at the same time. 3 were located near Marthas Vinyard One was located around 38N2645 74W4647.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/27/202137605/12/2021Guam SurveyingUSER: Launches occur everyday 9pm 1030 pm Our ground based receiver stays on 8-12 GPS, our radiosonde frequently drops to 0.It started October 10 2020 through November 26 2020 almost all of our night launches had half for more GPS dropouts. Now our issues are with daytime launches. Todays launch the radiosonde went from 6 GPS while on the ground to 0 when it was launched.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but reporting source did not respond.

Insufficient Information05/27/202137505/09/2021CYPRUS, LIMASSOLMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202137405/08/2021CYPRUS, LIMASSOLMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202137205/04/2021PELLOPONISOS GREECEMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202137005/02/2021North end Boca Ciega bay, FloridaMarineUSER: All satellites stopped receiving at noon and lasted for exactly 10 minutes when reception restarted.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/27/202137105/02/2021PANTELERIA ISLANDMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202136904/28/2021Eastern MediterraneanTransportationUSER: roughly 12 hours of gps spoofing upon departure from port Said Egypt. GPS signal rapidly shifted numerous times, position 6-8 miles off. Position dropped for 90 percent of the 12 hours. GPS aboard connected to ECDIS, RADAR,AIS, GYRO repeater panel, GMDSS suite.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202136804/23/2021Jeddah - 3nm before the port limitMarineUSER: For the length of our stay 23/0000 till 23/1900, we experienced intermittent reception or not at all (port approaches and alongside).

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/27/202136704/21/2021Malta ChannelMarineUSER: GPS signal lost for 2 minutes.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/03/202136604/18/2021East Mediterranean SeaMarineLost GPS signal for six-minutes from 1620 GMT to 1626 GMT.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/03/202136504/13/2021Eastern MediterraneanMarineGPS jamming begins, affecting both GPS units. Our position was @ 36-06N, 016-58E, and we were on a course of 100 T, with a speed of 17.8 kts. The GPS receivers had @ 8 satellites in view, but the Signal to Noise Ratio (SNR) of all satellites changed continuously from 0 to less than 30 for all satellites. Both GPS receivers were alarming, indicating a “loss of signal.” I switched GPS #2 to primary, because it also receives position data from GLONASS. This allowed our ECDIS to continue to function. The jamming was solid for 8 minutes..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/03/202135903/17/2021CaliforniaOtherMy GPS keeps going in and out saying satellite connection lost. I need this problem resolved as I am an over the road trucker.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/03/202135703/02/2021GeekHo, Pine Cay. Turks & Caicos IslandsTiming USER: It is an NTP server, but I keep track of how far my house wanders, and it went 40ish meters away from average.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/03/202135802/24/2021Campeche, MexicoTransportationUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information05/03/202135402/10/2021Between Malta and SicilyMarineUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference03/01/202135502/10/202125-50 miles NW from Port Said, EgyptMarineUSER: Signal lost on both units for about 2 hours. After that constant disturbance, but receiving position on one or another unit with some 5-7 minutes intervals. Back to normal signal on both units 10Feb2021 Other vessels in vicinity did confirm same issue with GPS signal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2021-004-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/03/202135302/07/2021East Central MedMarineUSER: The ship encountered total loss, last position:Encounter Feb 6-7.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference03/01/202135202/04/2021North of Pantelleria Island Med SeaMarineUSER: Vessel bound from Algeciras, Spain to Port Said, Egypt. Disruption began North of Pantelleria Island and has continued intermittently till east of Malta.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference03/01/202142302/01/2021Mt. Potosi (South of Las Vegas Nevada)SurveyingUSER: The interference at this station has been ongoing and intermittent throughout the day for close to a year at least. We recently installed a different antenna and the interference seems to be more identifiable as intermittent bursts throughout the day. It seems like there is communication that is on the L2 GPS and GLONASS frequency. When the burst occurs the L2 signal on both systems is eliminated. I do have screen displays of the satellite signal and the interruption as it occurs and I would be happy to send you a recording real-time. The number and name of satellites reported are not necessarily accurate as the disruption occurs throughout the day every day with varied satellite availability and location. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. Local interagency investigation for interference is ongoing.

Unknown Interference10/19/202135601/28/2021HoustonOtherInterference seems to be in the 1580-1600 MHz band.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. Update: Erroneous signal no longer present.

Unknown Interference05/03/202134701/22/2021EAST OF TAIWANMarineUser: THIER WAS LOSS OF SIGNAL FOR GPS.VESSELS IN VICINTIY ALSO REPORTED LOSS OF SIGNAL ON VHF. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference03/01/202134801/22/2021Enroute from Qatar to BahrainMarineUSER: departed Mesaieed, QATAR bound for Bahrain. Approximately 1 hour after departing Mesaieed we began intermittently losing our GPS feeds from both GPS Units. This issue has continue occurring for over 12 hours and we experienced GPS loss from 1-5 minutes at each occurrance. We made contact with two other vessels in the area to find out if they too were having these same issues (allowing us to rule out a wiring or other issue). These vessels reported that they too were experiencing the same issues. The vessel is presently at Anchor off Bahrain about 40nm Offshore and has experienced the issue again since anchoring. Of interest may be an AIS contact displaying as a 20 Meter long Pleasure Craft named SEA HOPE, Call Sign A9D275C. I am noting this because presently wind speed are approximately 40Knots and Seas are at about 3.0M, Not the normal conditions you would expect to see a pleasure craft holding station. This craft is about 6nm from our present location..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference03/01/202135101/19/2021Ellison BayMarineUSER: GPS NAIS disruption at tower at Ellison Bay, Wisconsin. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. The Federal Communications Commission conducted a local investigation. They identified the cause to be spurious emission from equipment collocated on the tower. GPS functionality returned with the elimination of the spurious emission.

Unintentional Interference03/31/202134901/16/2021FloridaMarineUSER: SV and DOP plot available on receiver shows a loss of satellites for about 45 minutes. The plot is a mess showing sats are most likely in and out causeing the position to be erratic and unusable. The same problem occurred again at exactly the same time on 23 January.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information03/01/202137301/16/2021GlobalSurveyingCNES has detected a repetition of IODE for PRN09/SVN68 on January 16th, 2021.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment on the reported matter and validated the observed IODC repetition. The discrepancy has been resolved.

IODC_10-Bit07/19/202134512/21/2020Luvkushnagar(Laundi), IndiaTransportationUSER: Tried many phones but GPS location is not found. One govt app is not working at the location but after 7-8 kilometre it is found working. This is happening since last one month.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information01/21/202134412/19/2020zwolle, The NetherlandsAutomobileUSER: sudden change in date/time, position seemed ok.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information01/21/202134111/28/2020Bull Lake DamSurveyingUSER: Performed a 24-hour observation on a control point with a 3-second collection interval. Error/noise was too great for OPUS to analyze the data file of collection points. 1D error was roughly 6 meters and 2D error was roughly 4 meters at the beginning of the observation.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Unknown Interference01/21/202134011/17/2020I5 north going through SeattleAutomobileUser: Getting message “unable to connect” on vehicle showing no gps on phone and location way off.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, including any information from equipment manufacturer, but the reporting source did not respond.

Insufficient Information12/15/202033811/15/2020Powell, TN 37849TransportationUSER: In Powell,TN, zip code 37849. For years, GPS has routed truckers onto E.Raccoon Valley Road from Old Raccoon Valley Road as a shortcut to Norris Freeway, state road 441. First, it is not a significant shortcut; only a few seconds difference if they had maintained their original heading. Second, and most importantly, when they try to turn south onto Norris Freeway from E.Raccoon Valley the result is always the same. The truck ends up blocking both lanes of traffic because it cannot make the turn and the trailer is sitting on its parking legs due to the elevation. The truck always has to be towed out of this position, blocking traffic for a couple of hours and because it is the midpoint of a fairly sharp curve, this is an accident waiting to happen. I’m requesting your help in getting this routing error changed. Thank you.

NAVCEN: NAVCEN provided the website information to GPS.gov for mapping issues. Also contacted the Knox County Public Works for further investigation to determine alternate safety precautions.

Mapping Issue12/15/202033911/15/2020Pacifica, CAMarineUser: While conducting a search near Pacifica CA , Unit lost GPS position on both receivers. Went into settings and one unit was receiving more than the other with one being near zero reception. Moved further offshore and south and was able to reacquire GPS position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. Federal agencies will continue to monitor and investigate the situation. NAVCEN will provide updates as new information becomes available.

Insufficient Information12/15/202033611/06/2020Peachtree CornersAutomobileUser: Most GPS units direct users to a parallel road instead of my address.

NAVCEN: NAVCEN provided the website information to GPS.gov to correct mapping issues.

Mapping Issue12/15/202033510/26/2020Laurelhurst, WAUser: No additional info known.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information12/15/202033410/20/2020Stockbridge and McDonough GATransportationUser: Kept reporting "GPS Network Unavailable" I reset phone twice but did not correct the problem. Wifi location worked when there was signal around.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information10/27/202033210/08/2020Horace Williams Airport, Chapel Hill NCSurveyingUser: I was performing a drone aerial mapping project in the area of Chapel Hill, NC, specifically at the abandoned Horace Williams Airport.Launched the drone, and it did not go to where I designated it to go and was appearing to want to fly away. Landed the drone and retried the mission with the same results. Drone acted like it did not know where it was. Drone equipped with onboard GPS capable of tracking both GPS and GLONASS SV. I also wanted to survey some points on the ground for reference for the mapping I was doing. I was using Survey Grade GPS receiver. I could see on the data collector that controls the receiver that I had at least 10 - 12 satellites visible, however, it was only locking on to 5. Of the 10-12 satellites visible, 2-3 of those were GLONASS SVs and the rest were GPS SVs.Finally, I was at this same site on the prior Monday and had no GPS problems or interference using the same equipment.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN recommended contact manufacturer for assistance. Requested additional information, including any information from the manufacturer, but the reporting source did not respond.

Insufficient Information10/27/202033310/06/2020Boston, MAMarineUser: Intermittent loss of position causing blank screen 10-15 times/day over three days.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners or users. NAVCEN requested additional information, including any information from equipment manufacturer, but the reporting source did not respond.

Insufficient Information10/27/202033010/05/2020Houston, TXMarineUser: Could not receive any SVs to my 212 while departing Cargil 2. Later during my outbound transit my 212 had no problem receiving SVs. Spoke with a pilot who experienced the same phenomena @ Cargil 2 while driving into the slip, lost all SVs. Possible GPS jamming from trucks nearby?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but reporting source did not respond. Investigation is ongoing.

Insufficient Information10/27/202033109/29/2020transiting inside Suez Canal N-boundMarineUser: DGPS available on both. We switched also to gps only but get same errors. Restarted them one by one interlinking the other with the systems, but get the same result.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/27/202032509/25/2020Mediterranean SeaMarineUser: Additional vessel in area were experiencing similar GPS failures.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032609/25/2020ItalyMarineUser: Both of our GPS where having satellites blocked causing signal loss. It happened off and on for about 3 hours. Called other ships in the area and they were having the same issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032709/25/2020Mediterranean SeaMarineUser: Intermittent GPS signal beginning at 0130Z which lasted for approx. 1-hour. Occurred again at 1030Z posn 35-20N 18-43E, and 1325Z posn 35-35N 17-40E for 15 minutes respectively.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032309/23/2020South East of ItalyMarineUser: During navigation in the Mediterranean Sea in the above mentioned position at 06:34 AM Local Time due to inference we lost signal from 3 GPS. Position Data Lost At 07:03 AM Local Time the signal for all 3 GPS returned and all equipment recovered.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032409/22/2020East of MaltaMarineUser: Ships in immediate vicinity are understood to be experiencing the same signal-loss issues.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-016-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032809/21/2020Port Hedland, Western AustraliaMarineUser: Intermittent but frequent loss of PPU Operations that appear to be GPS related as they lose position. PPUs receive Differential Corrections from a beacon some 200km away but that Beacon operates only on GPS Satellites, not any other constellations satellites.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. Update: Further investigation by reporting source revealed connectivity issue.

User Equipment10/20/202032209/16/2020Southern Gulf of SuezMarineUser: My guess is that we experienced GPS jamming. In March 2020, while in the ASRY shipyard, the Fairfax had two new GPS receivers installed; one Furuno, and one SAAB. The SAAB model receives both GPS and Glonass position signals, and sends both to the ECDIS. These positions are usually within 3 to 10 meters of each other - very accurate. Because we have experienced GPS jamming on this vessel, several times before, in Port Said and in the Suez Canal, we proactively made the SAAB GPS/Glonass receiver the Primary ECDIS position sensor, to help defeat any GPS jamming. It worked -- we never received alarms, or lost our ECDIS picture. Since the AIS has its own stand-alone GPS receiver, it makes sense that we would lose all AIS data during a GPS jamming event. The momentary loss of radar video could be explained as the ECDIS lost the GPS data, and switched to the Glonass position. Again, this is my own guess. If the problem had continued, I could have made the Furuno GPS the primary sensor, to see if we would experience the full experience of GPS jamming problems. I did not think of doing this until later, well after the problems disappeared.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/20/202032109/10/2020Beirut, LebanonMarineUser: Vessel is equipped with two identical GPS receivers. Both GPS units encountered intermittent disruption simultaneously. The disruption was first encountered briefly in Eastern-Mediterranean Beirut Lebanon coast. Complete loss of signals for a period of 1 to 2 hours.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference10/06/202031909/03/2020Las Cruces, NMAgricultureUser: Intermittent problem Have switched from RTK to Autonomous to SBAS and confirmed 0 satellites Have swapped out components but will cut out. It appears to be in this area We have also noticed interference on vehicle SAT radio interruptions Clear view no obstructions

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. There was no response to our request for additional information.

Insufficient Information10/06/202031708/31/2020Port Said, EgyptMarineUser: Vessel is equipped with two identical GPS receivers. Both GPS units encountered intermittent disruption simultaneously. The disruption was first encountered briefly in Eastern-Mediterranean Sea off Greece. Disruptions were again encountered with increased frequency and effect when our vessel approached the port of Port Said, Egypt. Each disruption caused partial to complete loss of signals for a period of 1 to 2 minutes. HDOP levels were observed to be in the range of 6. Restoration of signals were as abrupt as the disruption. The disruptions continued with lesser frequency as vessel progressed through the Suez Canal. About 45 nautical miles inside the Suez Canal from the Northern Entrance, disruptions ceased completely and since then both the GPS units have been functioning normally. A Navtex message (message number OA89. NTM 038/20) from Malta Radio dated 29th Aug 2020 warned mariners regarding "Harmful Interference to the GPS and GNSS".

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/10/202032008/28/2020Buenos AiresCommunicationsUser: I work as a engineer for Canal 9 of Bs. As. Argentina GMT -3, our transmission system uses the GPS signal. But every other week, more precisely every other Friday (every 14 days) it happens that between 01:25 pm and 01:35 pm some shift in the GPS signal happens since our 4 modulators with four different antennas present a type of failure. The 4 antennas are located in the same place.A few minutes ago the failure occurred and is systematic. Do you make any automatic adjustments during those hours?Thank you!

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. There was no response to our request for additional information.

Insufficient Information10/06/202031608/24/2020Gonzales, Texas USAAutomobileUser: Not the first time outages have occurred.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information09/10/202031808/22/2020Sterling, VirginiaResearchUser: Expected to track M-code on PRN 18 (SVN-75) but was only able to track Y-Code on L1 and L2 frequencies. Other M-Code capable satellites (PRN 15, 30, etc.) in view were able to track M-Code on both L1 and L2. Was there a disruption on PRN-18 regarding M-Code?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. There were no authorized GPS tests in the area. No correlating reports from interagency partners. L1 M-Code was tracked by at least one other R&D partner during the time frame. NAVCEEN requested additional information, but reporting source did not respond.

Insufficient Information10/27/202031508/21/2020Darjeeling, IndiaTimingUser indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but the reporting source did not respond.

Unknown Interference09/10/202031408/19/2020Hal-FarOtherUser: The Malta Communications Authority has investigated reports of GPS interference during July-August 2020. A source located outside Malta is causing this interference which is affecting land, maritime and aviation users.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference.

Unknown Interference09/10/202031208/15/2020Far RockawayTransportationUser: Today as well as Friday, we kept receiving messages on our cell phones that they could not connect to GPS.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. NAVCEN requested additional information, but the reporting source did not respond.

Insufficient Information09/10/202031008/14/2020North of Pantelleria IslandMarine

User indicated an intermittent problem that was otherwise unspecified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference09/10/202032908/04/2020GlobalSurveyingUser: CNES (Centre National d Etudes Spatiales, French Space Agency) has detected a repetition of IODC for PRN19, SVN59 on August 4th, 2020.The detection is based on a consolidated navigation message file, built from RINEX navigation files issued by numerous IGS stations. Could you please confirm the IODC repetition?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment on the reported matter and validated the observed IODC repetition. The discrepancy has been resolved.

ICD_Violation10/27/202030907/30/2020Suez CanalMarineUser: Intermittent alarm on all equipment connected to GPS

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/19/202031307/30/2020MaltaOtherUser: Local authorities were contacted and it had been confirmed that there are interfering signals from south direction.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference.

Unknown Interference09/10/202030807/29/2020Port Said, EgyptMarineUser: Vessel experienced intermittent outages from 1730 local departing Suez Canal to 2142 local at Lat 31-48.0N Long 031-51.6E. Position became erratic before failing entirely. Vessel resorted to manual fixing in DR mode when system erratic or failed.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/19/202030707/26/2020inside of Persian GulfMarineUser: We observed GPS interruption when vessel transiting in between K.A.S. and Iran. Date & time: 0907UTC 26-JUL-2020 Position: 27-10.1N 051-09.4E / <069>11’ from Ra’s Tannurah by Duration: 10minComment- Outage report received from Master of vessel Tanzawa. .

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference08/19/202030607/22/2020Chambersburg PATimingUser: 20.3.3.5.1.8 Special Messages.Sub Frames errors. Octal 252 Character Hex AA, not an allowed character in a special message. At a point earlier we were seeing parity errors on Word 4 for every SV in view. Seeing this on hardware in PA, NJ, MA, CO, CA, Munich, and Bangalore India

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment and determined, due to operational tasking, an unexpected condition was broadcast from subframe 4, page 17 of the GPS navigation message which may have affected certain user equipment. Subframe 4, page 17 data is allocated for special messages per IS-GPS-200.

ICD_Violation09/03/202030507/18/2020EdmontonUser: This has been ongoing in the city of Edmonton for quite some time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. There was no response to our request for additional information.

Insufficient Information08/19/202030406/17/2020Sao Marcos Bay areaMarineUser: ON 17TH JUNE 20 AT 0415LT"NO FIX ERROR" WAS DISPLAYED ON BOTH GPS RECEIVERS.GPS LOST SIGNALS EVERY 10 TO 15 SECONDS.ALL EQUIPMENT ASSOCIATED WITH GPS IN INS STARTED MALFUNCTIONING.THIS STABILIZED AFTER 2 HRS. THIS OCCURRED ON 18TH JUNE MIDNIGHT WATCH HOURS ALSO.THE SHIPS IN VICINITY ABOUT 4 MILES FROM OWN POSITION DID FACE SAME PROBLEMS.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment. There were no authorized GPS tests in the area. No correlating reports from other agencies. Space Weather Prediction Center indicated its possible this report of interference is due to equatorial anomalies.

Unknown Interference07/30/202030306/16/2020Downtown San FranciscoAutomobileUser: While driving a familiar route under same conditions as many times before, GPS signal became unstable, and position was several hundred feet wrong, condition persisted for about 40 minutes. While crossing golden gate bridge, location was shown as 1,000 feet west of bridge and error continued while on 101 northbound past Marin.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. There was no response to our request for additional information.

Insufficient Information07/30/202030206/07/2020Cyprus, LimassolMarineUser: No Fix, Unsafe, Caution, DOP ERROR from Cyprus to Beruit, Port of Beirut to about 100 NM South of the Port before it all cleared 6/7/2020-6/9/2020 0230 (-2)

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference07/30/202030106/05/2020GilbertSurveyingUser: Setup the base receiver and was not able to obtain a solution due to 0 GPS satellites. I did see 1 or 2 GPS satellites over the course of 10 minutes however these were intermittent. I took the receiver approx. 1/2 block away and then received up to 10 GPS satellites. Driving back to the previous location the GPS satellites drop to 0 again with the intermittent 1 or 2 over a 10 minute period. The GPS issue wasnt seen when working this site back in February of this year.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users.

Insufficient Information07/30/202029706/03/2020Mississippi River at Muscatine, IATimingUser: Recurring issue in Spring, Summer, and Fall since at least 2018 occurring usually multiple times per week. Issue not present or severely diminished in the winter. Issue present at all hours of the day. Can not correlate to time of day, weather conditions, or temperature.Occasionally happens to multiple devices at the same time, but one device sees this issue the most / first, suggesting directionality from the northeast.Duration of event is between several seconds and 24+ hours. Often lasts several hours.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. Investigation ongoing. Update: Reporting source has replaced equipment with positive results.

User Equipment07/30/202029405/14/2020SpotsylvaniaUser: This is based off of my GPS enabled running watch being unable to pick up GPS signal at my house, but it picks up the signal around a quarter mile away from my house.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. NAVCEN requested additional information, including any information from their equipment manufacturer, but the reporting source has not responded.

User Equipment06/16/202029204/18/2020Black SeaSurveyingUser: Multiple vessels in the Black Sea lost GPS and Glonass positioning, simultaneously. We are a seismic survey vessel with multiple DGPS receivers. Other vessels in our immediate vicinity also reporting loss of positions. Situation started at 06:17UTC and is ongoing at 07:45UTC. Occasional GPS satellite information being received but dropping out more than in.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. The report of interference is similar to that outlined by U.S. Maritime Administration in Maritime Advisory 2020-007-Various GPS Interference. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/08/202029304/14/2020Las Vegas areaUser: General question of GPS satellite system usability in Las Vegas area. Some observations after 04/14/2020 that satellites could not be used continuously.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. Issue subsided; reporting source will continue to monitor and update NAVCEN.

Insufficient Information06/16/202029104/09/2020ST. JOHN RIVER. ATLANTIC BEACH FLMarineUser: While transiting in the St. Johns river, in vicinity of Atlantic Beach, Fl a Coast Guard Vessel experienced a GPS outage. Losing both of the ships GPS receivers during their mooring evolution. Unit verified with another USCG vessel, at the pier, who was experiencing the same issue. Unit restarted both GPS displays with no resolve. After waiting approximately 20 minutes GPS signal regained and seems to be working properly.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies. Ships crew will continue to monitor GPS and provide updates.

Unknown Interference04/22/202028803/29/2020South of Hormuz TSSMarineUser: 2 GPS units aboard the newer is a Furuno GP-170 is only losing signal momentarily. SAAB unit has not received a position for 6 hrs.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with the U.S. Maritime Advisory 2020-001-Persian Gulf, Strait of Hormuz, Gulf of Oman, Arabian Sea, Red Sea, Gulf of Aden, and Indian Ocean-Threats to Commercial Vessels by Iran and its Proxies on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference04/22/202028703/24/2020Warrenville, IL USAAutomobileUser: I used GPS for a trip immediately prior to this anomaly, without issue. When I attempted to enter my next trip leg, I noted an anomaly. My GPS apps could not locate my vehicle correctly and could not plot a course to my destination. The map display spun around multiple times, and at times placed my vehicle at the end of nearby dead end roads and even in the middle of a nearby field. I restarted the apps, to no avail. I restarted my phone and the bizarre behavior continued. About fifteen minutes after first noting the problem, I restarted my phone again and my GPS apps began working correctly. I do not know if it was a device issue or a GPS system issue. As of this date, I have used GPS twice on this device, without issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. There was no response to our request for additional information.

Insufficient Information04/22/202028503/16/2020Medford, OregonTimingUser: We use GPS timing servers across our network within the CONUS. Across our network at approximately the same time, the timing servers went into holdover. As this issue was seen in multiple places, we do not think there were any issues with the hardware or software. We are trying to understand if something impacted the GPS satellite systems ability to provide timing on March 16th, 2020.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN requested additional information about the equipment, if issue is on going, or actions taken to correct the problem. There was no response to our requests for additional information.

Insufficient Information06/16/202028403/13/2020Central Mediterranean SeaMarineUser: NO GPS SIGNAL on 2 independent units.Other ships in vicinity reported the disruption over VHF Ch 16.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with the U.S. Maritime Advisory 2019-013 Eastern Central Mediterranean Sea and Suez Canal GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference04/03/202029003/10/2020Colorado Springs, COOtherUser: Since the morning of 3/10 we have seen low accuracy GPS readings for our fleet of tablets which is still ongoing. This results in GPS locations being off from a couple of blocks to a mile with the inaccuracy being more pronounced when stopped. This has occurred throughout the Colorado Springs area at all times of the day.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users.

Update: The mobile provider has identified the issue and is working on an update to correct it.

User Equipment04/22/202028303/09/2020BoulderUser: Noticed irregular signal multiple times near the same block during weekdays.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. Federal agencies will continue to monitor and investigate the situation. NAVCEN will provide updates as new information becomes available.

Insufficient Information06/16/202028203/04/2020Everett Turnpike Route 3 & E Dunstable RdAutomobileUser: I have had a number of intermittent GPS issues within 1 mile of this location over the past year. GPS drops almost exactly 10 mph and the location plots diverge for approximately 1km parallel to the actual track. I took a picture of the GPS track showing the deviation. Contact me if you would like a copy of the track picture. I had previous similar incidents in the same vicinity.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. Federal agencies will continue to monitor and investigate the situation. NAVCEN will provide updates as new information becomes available.

Unknown Interference04/13/202031103/01/2020Bothell, WAAutomobileUser: Greetings, pretty much the whole year I need to recalibrate maps every ten minutes to get a good gps signal. My job requires it as I will not receive offers with a weak signal. I have purchased 2 different phones within the last year to fix the issue but it is still present. I work mostly in Woodinville, Bothell, Kirkland and Redmond Washington. Multiple people said they are experiencing the same issue and it is strange because I heard space x recently placed another satellite into orbit for Washington state. Thanks for all that you do.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. Recommend contacting manufacturer for assistance.

User Equipment10/06/202028002/20/2020Dulles AirportAutomobileUSER: This occurred in Chantilly, VA around 4pm EST. I was on Rt. 50 heading East near Avion Pkwy close to Dulles Airport. The GPS navigation in my vehicle stopped working. When I looked for more information in the GPS it displayed no bars for a GPS satellite signal. This outage continued until the end of my trip in Reston, VA. I made two attempts to turn off my vehicle and restart the navigation during the trip, but this did not work to restart my GPS navigation. It was when I stopped the vehicle, stopped the engine, and got out of my car for 10-15 minutes that the GPS system resumed activity. I hope this is just an anomaly, however being so close to airport, I have to wonder if something else was occurring at the time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN requested additional information about the equipment, if issue is on going, or actions taken to correct the problem. There was no response to our request for additional information.

Insufficient Information03/09/202027902/17/2020Rehoboth MAAutomobileUSER: Position shown on maps was off by approximately .5 mile to the west. Also had same occurrence last night while in the same general area. When I noticed the issue on my Nav radio, I checked location on my iPhone and it was consistent with the radio in showing the wrong location.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN requested additional information about the equipment, if issue is on going, or actions taken to correct the problem. There was no response to our requests for additional information.

Unknown Interference03/09/202028602/12/2020WorldwideOtherUser: In February 2020 (Feb 12th, 13th, 15th and 16th), PRN19 has broadcast several ephemeris and clock data set with the same IODC, although the data was different. This does not respect the IODC repetition rule in §20.3.4.4 of IS-GPS-200.

NAVCEN: The GPS Operations Center reported that the cause of the IODC repetition error was the result of an issue experienced with the ground control system. The problem has been corrected.

ICD_Violation06/16/202027701/20/2020Gibsonton, FLAutomobileUser: I was driving following my GPS when all of sudden it lost GPS signal on the highway. I checked my vehicles GPS also and it could not lock on to me. It finally returned after about 20 mins but something must have knocked it out.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN recommends continuing to notify us if symptoms in the area continue.

Unknown Interference02/25/202027601/14/2020Paso PalmaUser: My GPS position is changing. Beginning on 1-14-2020 almost every day, why is that? I measure from the same point at my home.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

We recommend user ensure equipment software is up-to-date, refer to your equipment manual, or contact your equipment manufacturer for further assistance. NAVCEN requested additional information about the equipment, if issue is on going, or actions taken to correct the problem. There was no response to our requests for additional information.

Insufficient Information02/25/202027501/13/2020BARCELONA, SPAINMarineUser: We were alongside in Barcelona same day from 12:18 till 16:23 UTC. We just restarted both units without any success - NOT SAFE -indication persists.During our stay alongside it was brief moments when NO FIX was displayed.DOP at not very high levels (1.7 / 3.0) In GPS manual it says that if DOP is close to level 6 the GPS will show 2D position, only.My portable GPS receiver (Garmin / hand-held) set on GPS satellites shows correct positon (checked alongside) and has No. 5 /13 /15 / 17 /20 / 21/ 24 /28 /30 /38 satellites locked - no.7 and 19 on sightI hope our answers will help you !.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer.

Update: User worked with the equipment manufacturer conducted a reset procedure and checked settings, operations back to normal.

User Equipment01/28/202027301/02/2020Dubai, UAECommunicationsUser: At around 2AM(GMT+4) 2nd Jan 2020, around 100 outdoor wireless broadband CPEs started reporting loss of GPS satellites. GPS synchronization is necessary for our radio devices which kept dropping link as a result for 8-10 hours due to GPS receiver switching between GPS lock and satellites lost(very low SNR). The units were rebooted and everything got back to normal immediately. Everything seems to be running fine for past 36 hours since the reboot.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with U.S. Maritime Advisory 2019-012 Persian Gulf, Strait of Hormuz, Gulf of Oman, Arabian Sea, Red Sea-Threats to Commercial Vessels by Iran. You can find the full text on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference01/28/202027401/01/2020CABAOtherUser: When the equipment tries to establish a GPS link, when it reaches 80%, the controller indicates "Calibration Error In The Compass, See Another Place or Calibrate It Again", if you try to recalibrate the compass the screen indicates " Do Not Know You Can Calibrate The Compass Without GPS" and this is a vicious circle regardless of where you try to perform the operation. From the little I found on the web, the problem occurs "Worldwide", which rules out an inconvenience in my teams or even more in my country. By way of verification, I share a link with manifests from hundreds of users from all over the world with the same inconvenience. Could you please give me some information about it? Thank you in advance and have a nice day. https://community.gopro.com/t5/Karma/Karma-won-t-start-amp-compass-calibration-failed-no-gps-signal/td-p/488828 "

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

There is a known issue with how the equipment handled the updated GPS week number value.

NAVCEN recommended user to contact the manufacturer for additional assistance.

User Equipment01/28/202029601/01/2020Lancaster CA, Hwy CA-14 crossing Ave JTransportationUser: This location, on CA-14 northbound crossing over Ave J in Lancaster CA has a permanent disruption of GPS reception noticed over 6 months, driving daily in early evening and late evening, and is detected by 2 separate models of Garmin automotive GPS units. There is no overhead signage that could cause a drop out. The drop out and loss of reception covers a span of approximately 200-300 yards centered on the Ave J overpass.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other agencies or users. Investigation ongoing, NAVCEN will provide updates as new information becomes available.

Insufficient Information07/30/202027212/28/2019Tripoli LibyaOtherUser: Our vessel is underway from Greece to Tripoli Libya. When our vessel is at 50nm from Libyan Port. Disruption or interference of GPS Signal started and both GPS receiver is affected. We reboot our GPS but still the disruption still exist, despite of how many times we reboot our equipment. Until we arrived at Tripoli Port interference still exist with an interval of 20-30secs GPS Lost signal again. We stayed at anchor for 2days already and yet no improvement of the disruption and it continues everyday. It is not the 1st time it happened but every time we are inside of 50nm from Tripoli Libya.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference01/28/202027012/06/2019Naples, FL Orange Blossom RdUser: This entry to the Autumn Woods Association is closed. GPS directs vehicles through this entry and they damage property. The correct entry is Goodlette Frank Road.

NAVCEN: User was provided information on how to contact mapping software providers to update their location details.

Mapping Issue12/20/201926912/03/2019MELLITAH,LIBYAMarineUSER: While approaching Mellitah Port,Libya both GPS lost signal and was showing No fix.GPS was receving Signal Intermeditely and again losing at a interval of 5 Minutes.Restarted both GPS,dignosis carried out Still GPS sensor was unable to hold on to Satellies.After anchoring at Melllitah port and after 6 hrs the GPS lost Signal ,On restarting the GPS,No error was showing and Both GPS working Satisfactorly

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference12/20/201926711/29/2019Baltimore Key BridgeTransportationUSER: Use of any application, Waze, Maps, Google Maps could not connect to GPS from the Key bridge to East of the Key bridge.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment12/20/201926611/25/2019Misurata libyaMarineUSER: Before arrival to Misurata Port, Libya about 15nm from shore DGPS signal becomes intermmitent. Until arrival to anchorage to port. We stayed 72hours on port and DGPS Signal still lost.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners. This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference12/20/201926311/08/2019Santa Ana - downtownCommunicationsUSER: For the day, the compass apps on the iphones, and the Garmin were all at about 93 ft accuracy. Usually all are at +/- 20. Navigation app kept losing us, sending us in circles, etc. The geocaching app on the phones also sent us in circles, with only +/- 93 ft accuracy.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

Many times in a downtown area when GPS does not have a clear sky view multipath errors are possible and likely. These errors can often cause both position and speed errors. We always recommend you ensure your equipment software is up to date, refer to your equipment manual or contact your manufacturer for further assistance.

Other01/28/202026211/07/2019Litchfield, CTAutomobileUSER: Was trying to get directions to North Haven, CT. Was told by apple maps and google maps that the address is not routable from this location tried many different other addresses, all with the same result. Powered off phone, powered back on, same result. Around 9:10 it started working again. Above times are times I am certain it was not working. This is the first time GPS has not worked for me. There is nothing wrong with the phone that I can tell, it is fully updated, had a full battery charge, was plugged into the charger in the car regardless.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

NAVCEN can not verify function of applications or network service provider. We recommend letting your provider know about the issues you are experiencing.

User Equipment11/27/201926511/04/2019MesaTransportationUSER: I have had a disruption to all of my mail service. I do not know if there was a recent update to the GPS system. I have ordered packages from 4 different sources 2 of which I previously ordered from and had no issues. For some reason the Unit number sometimes shown in forms as Apartment is not coming up correctly and all of my packages are being returned. One of the companies I ordered from told me that the Unit number is showing as part of the street address. Was there a recent update that is causing this. I have had no problems with delivery up until the first of November.

NAVCEN: User provided information on how to contact mapping software providers to update their location details

Mapping Issue11/27/201926111/03/2019saudi arabiaAutomobileUSER: Thousands of vehicle tracking GPS devices stopped detecting the GPS signal at the same time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

NAVCEN spoke with the equipment manufacturer and they stated that it is associated with the week number rollover and are working with customers.

NAVCEN recommended user to contact the manufacturer for additional assistance.

User Equipment11/27/201926010/25/2019Delray BeachAutomobileUSER: Vehicle Nav was unable to connect intermittently.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

Reporting source stated he had GPS on another mobile device. Recommend user to contact the manufacturer for additional assistance.

User Equipment11/27/201925910/22/2019Port SuezMarineUSER: While approaching Suez anchorage area at 0940 LT ( 1140 UTC/22-Oct-19 ) about 29 37.4N 032 33.7E POSN , GPS interference detected in both GPS .V/l GPS malfunctioned and BOTH GPS showed error no. 212 in alarm window , Loss of position , NO FIX.As per Makers manual GPS error Reason : Interfering object between satellite and GPS receiver .Vsl called nearby vsls in vicinity to confirm if they also received the same error , Vsl STI ELYSSES replied even they got the same error for GPS . Vessel GPS operationalizes when vessel entered Suez Canal at 1105 LT (0905 UTC) / 23-Oct-19 at 29-56.5 N /032-34.3 E

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source has not responded

Unknown Interference11/27/201926410/22/2019many US locationsTransportationUSER: Provides telematics devices to the Transportation industry. We use GPS to provide location data for commercial vehicles and leverage this to enable Electronic Logging Devices for them to work correctly and record drivers hours of service information to ensure they are compliant.We had many devices working correctly, then suddenly on October 22 2019 we started losing GPS position data and this has been sporadic ever since.Logs showed that there were 13 SAT in view. But the data said zero satellites tracked. This has not been seen before.What event occurred that might have made this happen?

NAVCEN: User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source has not responded.

Reporting source responded and stated that it was a software issue.

User Equipment11/27/201925810/21/2019Off Misurata, LibyaMarineUSER: Initial signal loss was at 04:30 LT which lasted for about 4 hrs. Now signal is intermittent.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source has not responded

Unknown Interference11/27/201925410/15/2019Poland/EuropeOtherUSER: We are company who sells GPS devices. From morning most our customers reports(from polnad and europe) a problem with GPS operation. GPS does not fix position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

NAVCEN recommends further evaluation of software and check availability of GPS with other receivers.

Update: Reporting source responded and stated it was a sopftware issue.

User Equipment10/24/201925510/15/2019Piraquara, BrazilAviationUser: We lose the signal over a prison. Nearest mountains and dangerous area.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN recommends the reporting source contact the country communications agency for further information in that area.

Unknown Interference10/24/201925610/14/2019North Side of West Bay bridgeOtherUser: Below is the customer service response regarding the failure of the unit to properly display my location or lock onto the collar. I am so sorry you are having problems with the GPS lock, I have some good news and I have some bad news. The good news is it is not the equipment. The bad news is we are currently experiencing issues with the satellites that we use for our systems. This is not just affecting us but other GPS devices as well. Our engineers are diligently testing and working to find a resolution. As soon as one is found, I will gladly let you know. I am so sorry for all the issues you have had."I am searching to confirm this "satellite problem" therefore my reason for this report. I am eager for a response as soon as possible Please.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

Update: NAVCEN spoke with the reporting source and he acknowledge that he had GPS on other devices. Equipment manufacturer has stated that they are currently working on the issue.

User Equipment10/24/201925710/14/2019Cedar ParkAutomobileUser: Happened on several mobile devices. All navigation apps do the same thing, it says "No GPS, Showing Approximate Location" I have reset location, privacy and network settings, power cycled device, updated software and still the issue remains.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

We recommend the user to contact their service provider for assistance. We requested additional information, including any information from their provider but the reporting source has not respond.

Insufficient Information10/24/201925210/05/2019Mt. Vernon, Baltimore, MD, continuing northbound on rt 83User: On two separate cellphones, the GPS keeps having difficulty pinpointing the exact location. It will start to give the right directions, then think we are on another road and start giving directions for places nowhere near us.

NAVCEN: Issue was specific to one application on the phone while other applications still worked. User was provided information on how to contact mapping software providers to update their location details.

Mapping Issue10/11/201925010/01/2019XanthiSurveyingUser: Initially, the device observes many satellites. Then, accidentally the GPS device does not have none of them (and it seems that there is no satellite above).

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other inter agency partners.

Update: After further investigation reporting source determined the equipment required a software upgrade.

User Equipment10/11/201924809/08/2019Shanghai, ChinaMarineUser: After docking in Shanghai, China the GPS receiver was displaying incorrect position, speed and an audible beeping alarm. We believe it was due to interference.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

NAVCEN recommends to report the issue to the nearest communication authority. We also recommends all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference is present.

Unknown Interference10/11/201924209/02/2019Shanghai, PRCMarineUser: Vessel is at berth working cargo in Shanghai experienced GPS issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other interagency partners.

User encouraged to report the issue to the nearest communication authority.

We recommend all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference is present.

Unknown Interference10/11/201924309/02/2019Shanghai, PRCMarineUser: Vessel fast at container terminal working cargo. Speed and sometimes position jumping on all three units plus cell phone applications.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

NAVCEN recommends to report the issue to the nearest communication authority. We also recommends all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference is present.

Unknown Interference10/24/201924008/30/2019Aarhus, DenmarkTimingWe observe pps (pulse per second)outages on several installations in Denmark, Iceland and Finland. The issue started around the 30 of July. Probably earlier but not that frequent. The number of outages have increased now and become severe. We observe 4 time windows during the day at which outages occur at all installations at most days since 30 of July: 03:04 - 04:0607:37 - 07:4918:23 - 18:53 21:08 - 21:30 (all times in UTC)The start time of the outages drifts by about 4 minutes at each day compared to the previous day.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User is working with manufacturer.

Manufacturer has provided an update to NAVCN stating that they have issued and tested a firmware update to correct the outage.

User Equipment09/11/201924708/21/2019South of Mobile, AlabamaMarineUSER: For a period of about five minutes, three independent GPS systems lost position fix. Restarting the units did not correct the issue. Near the end of the event, each device acquired and lost position fix for a few seconds. Afterward all regained stable position fix. Outages like these have been occurring regularly, typically between 18:00-19:30 UTC.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. The GPS disruption report appears to correlate with a nominal rise in DOP over the disruption location, however, there are no indications that this would result in the loss of GPS signal that was experienced by the user. The GPS Operations Center can only verify constellation performance in the disruption location at the specified time, and cannot investigate receiver issues experienced. The GPS operations center recommends contacting the receiver manufacturer for further troubleshooting.

User Equipment11/27/201923908/19/2019ManassasCommunicationsUser: Manufacturer of portable Iridium devices with built-in GPS receivers. Over the last week we have experienced intermittent but regular interruptions of our GPS reception.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or inter-agency partners.

NAVCEN requested additional dates and times of possible outages.

User no longer experiencing outage.

UPDATE Interference came back but reporting source was able to determine the cause.

Unintentional Interference10/11/201923608/18/2019Spring, TXAutomobileThe time and date in the vehicle have gone blank, in addition, the GPS signal the vehicle is receiving shows that it is receiving the date of 12/31/1969 at 13:59:59. This has been going on for a few days, but the date and time remain the same and are not changing.

NAVCEN: As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. Requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

NAVCEN spoke with manufacturer and they are developing a fix.

User Equipment08/27/201923708/18/2019Albany, New YorkAutomobileUser: It appears that many, possibly vehicles lost date and time functionality due to a GPS satellite issue. Other manufacturers may be impacted, but this is unknown.Sample of impacted customers: https://www.cargurus.com/Cars/Discussion-t73000_ds1053034

NAVCEN: User encouraged to contact their equipment manufacturer for assistance. This is an ongoing issue with the vehicle clocks no correlating reports on other GPS systems. Many users have indicated that a factory reset may resolve the problem.

NAVCEN spoke with manufacturer who stated it is because of week number rollover and they are sending out updates.

User Equipment08/27/201923808/18/2019Austin, TxAutomobileUser: Vehicle clock gets time from GPS. Clock went blank and has yet to recover. Called dealer, and they said there is a known issue with satellite.

NAVCEN: User encouraged to contact their equipment manufacturer for assistance. This is an ongoing issue with the vehicle equipment. There has been no correlating reports on other GPS systems. Many users have indicated that a factory reset may resolve the problem.

NAVCEN: Manufacturer acknowledged the issue is likely related to the GPS Week Number Rollover. They are working on a firmware update to correct the issue.

User Equipment09/11/201923508/14/2019Alexandria, EgyptMarine-Disruption was steady and consistent for the first period (60min.) followed by a series of brief, intermittent losses of DGPS -DGPS was observed tracking between 0 (ZERO) and 4 (FOUR) satellites during the disruptions. -VHF voice polling of other (foreign flag) ships in close vicinity confirmed that they too were experiencing similar outages -Only 1 (ONE) DGPS unit was affected, confirmed same for other vessels in vicinity.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference08/27/201923308/12/2019EL SHAIKH NOBARAK, EGYPTMarineGPS CONNECTED DEVICES (GYROCOMPASS, CLOCK) EXHIBITED FAILURE FIRST, FOLLOWED BY POSITION FAILURE ON GPS UNITS THEMSELVES. APPROXIMATE EXTENT OF INTERFERENCE/FAILURE - 60 MINUTES INTERMITTENT.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference08/27/201923408/12/2019Mobile, AlabamaMarineOver a period of about ten minutes, three independent GPS systems (two MX612, and one 7000 118-530) lost position fix. Restarting the units did not correct the issue. At the end of the event all three systems regained a stable position fix.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

We recommend all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference may be present. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference08/27/201923208/06/2019South of Sicily in the Mediterranean SeaMarineWhen No fix alarm was showing, the HDOP values were fluctuating between 1.2 – 1.5

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference08/19/201922908/03/2019KarachiCommunicationsBlue dot is blue dot jump around and blue is 100 meter away.

NAVCEN: User provided information on mapping software.

Mapping Issue08/07/201923008/01/2019East of MaltaMarineUser: 01 Aug 2 GPS receivers have lost sat signal completely. 2 to 4 satellites started to be visible within next 3 hrs. All GPS receivers become fully operational only after 6 hrs from the beginning of interference. All ships in VHF range reported similar case at that time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference08/19/201922607/24/2019Sabratha Oilfield - Offshore LibyaMarineLoss of all sat positioning reference systems. Problem started when sailing from Malta. Total loss of GPS and DGPS signals (provided by Veripos). Other vessels experience same problem. Time period w/o receiving signals seems to be erratic. From 10 minutes to several hours. No pattern. Seems to be jamming. Satcom systems also affected. Service providers suspect military interference or equivalent.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source responded with manufacturer stated issue may be from local interference.

Unknown Interference08/09/201922207/23/2019AT SEAMarineUSER: VESSEL NAME NEREUS ISLAND

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment and determined it to be healthy, stable and robust during that time. It continues to provide precise positioning navigation and timing information to military and civilian users around the world.

This report is similar to that in the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean located on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. We also recommend all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference is present. NAVCEN requested any additional information, including communication authority or equipment manufacturers response details. Reporting source did not respond.

Unknown Interference08/07/201922107/18/2019New ZealandAviationUser: Airways New Zealand is experiencing dropouts of ADS-B ground stations for 2-3 hours yesterday and has started again today, commencing around 0300 UTC.Sites report.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

We recommend user work with eqipment manufacturer and verify software application. NAVCEN requested additional information, including any information from their equipment manufacturer. Reporting source is working with manufacturer.

User Equipment08/09/201922007/16/2019Port of ShanghaiMarineUser: Upon arriving to dock in Shanghai, a U.S. flagged MV master checked ECDIS at the AIS to see if their berth was clear. Another ship on the berth appeared to be in the channel making 7 knots (kts) speed over ground (SOG), but then disappeared from AIS. A few minutes later she was back and at the dock, then underway again, 5 kts, 2 kts, 0 kts, in the channel, then back at the dock, then gone. This pattern repeated multiple times. It turned out the other ship was actually all fast the entire time. Later, while the MV was turning in the river off the same berth, both GPS units lost their signals, no position, no SOG, multiple alarms on various integrated equipment. The GPS signal would come back for a minute and then be lost again. This continued to the dock and has continued. The GMDSS GPS is experiencing the same thing. Master suspects GPS signal jamming is occurring at this berth. Vessel checked all antennae connections – all connections are secured and dry. There have been no other issues with these units.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to report the issue to the nearest communication authority.

We recommend all users share their reports with their equipment manufacturer. This real world feedback can help manufacturers improve products by enabling them to operate in an environment where GPS interference is present. User acknowleded local interference likely the cause of the issue.

Unknown Interference08/09/201921607/11/2019JodhpurUser: Gps receiver in my mobile showing my position 80 km away from true location ..

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference08/07/201921707/10/2019PORT SAID, EGYPTMarineUser: Complete loss of GPS signals this afternoon when exiting the Suez Canal, 10 July 16:03 LT from km 4.5 Lat 31-12.5N Long032-20.4, just as Suez pilot was disembarking. Outage lasting for approximately 90 minutes. The signal came back intermittently at 17:28 LT Lat 31-26N Long 032-24E, and was stable by 18:00.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment and found space weather may have impacted GPS performance at the location. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report also correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference07/22/201921507/08/2019La Paz, BoliviaOtherUser: Problem about 1024 weeks start to appear on July 8, 2019 instead of April 6, 2019.On July 8, 2019 the GPS reports date November 22, 1999. Hours, minutes and seconds are correct.

NAVCEN: User acknowledged the issue is likely related to the GPS Week Number Rollover. They are working with their equipment manufacturer and expect a firmware update to correct the issue.

User Equipment07/22/201921407/03/2019LibyaMarineUSER: No fix

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or inter-agency partners.

User encouraged to report the issue to the nearest communication authority.

NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference07/22/201923107/01/2019Santo DomingoCommunicationsMobile devices struggiling to fix position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. Requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference08/19/201921206/26/2019PORT SAID, EGYPTMarineUser: SIGNAL INTERRUPTION HAPPENED AS WE WERE DEPARTING PORT SAID NORTHBOUND INTO THE MED. INTERRUPTION CONTINUED INTERMITTENTLY FOR APPROX. 2 HOURS.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference07/11/201921106/25/2019MadridUser: I have detected that GPS SVN49 (IIRM7) has been broadcasting an BPSK signal modulated with alternating 0 and 1 at the L1 frequency. The signal is clearly visible on a spectrum analyzer as two peaks at 511.5kHz from the L1 centre frequency, whenever SVN49 is in view.This has been ongoing over the last few days and continues.I have read that this satellite was decommissioned in 2011, so I wanted to ask if this is normal (I just noticed its signal by chance during some unrelated tests), if it is due to some tests with the satellite or if its an anomaly.

NAVCEN: To confirm this is not a problem with the GPS broadcast signals, NAVCEN contacted the GPS Operations Center who stated the signal you detected represents the current nominal status for SVN49.

SVN49 exhibits a known distortion due to internal multipath resulting in degraded performance. It is currently set in an "unhealthy" state and removed from the constellation to prevent any adverse effects on users. The description of the signal resembles the non-standard code the satellite will display when not in use for other testing purposes.

None07/12/201921006/20/2019Sabratha Field - Offshore LibyaMarineUser: Total loss of all GPS and GLONAAS satellites linked to both our DP PRS and navigational DGPS. All vessels in report same issues.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to report the issue to the nearest communication authority.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference07/01/201922706/20/2019TRIPOLI, LIBYA. VALLETTA MALTAMarineUser: CENTRAL MEDITERANNEAN CONTINUOUS DISRUPTION BETWEEN LIBYA AND MALTA.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from interagency partners.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference in the Mediterranean on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source did not respond.

Unknown Interference08/19/201920606/12/2019South of Odessa / UkraineMarineUser: GPS signal found to be disrupted, with all due consequences for vessel navigation equipment.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Unknown Interference07/01/201920906/12/2019Carson City, NVTransportationUser: I detected a few transient RFI events at CORS DOT1 across JDAYs 163 - 164 (Jun 12 - 13). I compared the events at other CORS sites in and around the Public Testing notice for Nellis RFI; these do not correlate to RFI detected at Las Vegas CORS sites on same days. The events occur around 0743 - 0830 for roughly 20 minutes. The SNR / C/N0 measurements appear indicative of a low-powered emitter without line-of-sight to other CORS near Carson City, NV. Trailing spike indicates possible noisy / cheap RF device. Happy to share my data, screen shots, plots. I am located in Colorado Springs, CO and use the site in NV remotely. Have contacted site owners and will continue observations.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

Report Closed.

Unknown Interference08/07/201920706/11/2019Cumberland, MDTransportationUser: Over the past week, we have been experiencing issues with our GPS system reporting a high HDOP value. We have a system installed on our locomotives called Positive Train Control (PTC) that uses GPS to validate a train location and requires a certain level of accuracy from GPS. We have seen the HDOP value rise from an average of 0.9 to 2.2 in the past week. We are inquiring if there have been any changes made that could account for the sudden increase in HDOP values?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. HDOP average at the point of interest was reviewed between 3 and 11 June and found to be 1.5. There were times when the maximum HDOP value for the day reached 2.5, but only for a few minutes. These values are typical historically for the area. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

Update: User worked with the equipment manufacturer and resolved the issue.

User Equipment08/19/201920506/03/2019Goodyear, AZOtherUser: Off Road travel, outage cleared

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information but the reporting source did not respond.

User Equipment06/12/201920806/02/2019OklahomaTransportationUser: Equipment on railroad locomotives is showing diminished position accuracy. Since June 2 across a fleet of several thousand locomotives in the US the positional accuracy is decreasing. This decrease is documented by lower average # of satellites received and higher HDOP values reported by the receiver. An alarm is generated by our system when the HDOP reported by the receiver in the GPGGA message stays above 2 for 10 minutes or more. While admittedly not completely accurate, this makes a convenient marker for diminished accuracy. This alarm was generated by 6 trains in Oklahoma June 2nd but has been seen from the east coast to the west coast in the days since. A similar by possibly not related issue occurred in the Midwest December 7 of 2018 with roughly 500 trains generating this error over the day. The alarms did not repeat until June 2nd. Previously this alarm was not seen in 2016-2018. In addition, the system can mark when the train passes certain surveyed locations along the track like a wayside signal. If the GPS location of the train is not within a certain distance from the surveyed location when passed, then another alarm is generated. This alarm was raised less than 5 times in the first 4 months of 2019 but has been raised 15-20 times in June so far. This appears to be another indication that the accuracy of the position fix has diminished. There have been no changes to the GPS receiver firmware in the last 2 – 3 years. We have been unable to correlate this diminished accuracy to reported satellite outages. Further information in graphical or spreadsheet format is available.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer.

User is working with equipment manufacturer.

Update: User worked with the equipment manufacturer and resolved the issue.

User Equipment08/19/201920406/01/2019Cornwall, CTOtherUser: Prior to this main outage, earlier in this trip there were a few brief blips of erroneous positions, starting in Peekskill NY, showing erroneous position. I have used this GPS for over a decade and never saw it have problems like this in wide open spaces. I had tried turning the GPS off and forcing it to "re-learn" the satellites. That did not help. It came up with the (presumably) same three and reporting weak signal. As I continued my travel it started tracking again at 14:37 positionin N41 59.508 W73 19.817

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information but the reporting source did not respond.

User Equipment06/10/201922805/30/2019Tokyo, Japan. Santa Rosa, CATimingThe receiver logged anomalous time of week being received from PRN 25 that was over 1000 seconds in the future beginning at WN 2555, TOW 429012 when PRN 25 reported WN 2555, TOW 430068. This persisted for over 4 minutes with the TOW from PRN 25 frozen at 430068. It was observed at multiple locations in Japan and also in California. PRN 25 was being tracked both in Japan and California at the time of the anomaly.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

NAVCEN requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

User Equipment09/11/201920305/23/2019San Mateo, CA to Palo Alto, CAAutomobileUser: Both built-in and mobile phone GPS indicated that I was in a different area than I was in while traveling between Foster City, CA and Redwood City, CA. Additional info: My satellite radio was offline at this time. By the time I reached San Jose, CA, systems were functioning normally again.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information but the reporting source did not respond.

User Equipment06/10/201920105/20/2019Port Said, EgyptMarineUser: Problem commenced when vessel arrived to the above mentioned position (this is Sea Terminal, vessel is moored alongside of Sea Buoys)off Port Said. First day 20/May/2019 it was continuously, every 5 mins GPS position lost. Second day, 21/May/2019 frequency of position lost reduced to very 20 mins position lost. Vessel is equipped with 2 DGPS units and fault caused on both of them. Following alarms / warnings observed on the screen during subject DGPS fault: 1. Alarm, No fix; 2. Alarm, HDOP over. End of report.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. Reporting source responded the issue has resolved.

Unknown Interference06/03/201920205/17/2019Lancaster, CAOtherSynopsis: 4 [equipment] were powered on between approximately 2030Z and 2100Z on 17 May 2019 in Bakersfield, CA. They were then flown aboard private aircraft enroute to Laughlin, NV. Despite being in what should have been a "hot start" mode, none achieved a GPS fix until 2200Z. Of particular note, three of the units achieved lock within 30 seconds of each other, despite being separated geographically by almost 100 miles. This seemed to suggest an external factor may have been involved.Detail: Five [equipment] units (SiRF Star III chipset) were used to log positions of aircraft participating in an air rally event. Note the [equipment] is a retail data logging "puck" being used in the aircraft for supplemental logging, not an air navigation application. The units log NMEA GPGGA sentences at 1 second intervals when a fix is available, but do not include the satellite count.Participating aircraft flew from Hayward, CA (HWD) to Bakersfield, CA (BFL) to Laughlin, NV (IFP).Units were powered on prior to takeoff and turned off after landing. During the first leg from HWD to BFL, all units operated properly on board the participating aircraft.During the second leg, from BFL to IFP, four units were powered on between approximately 2030Z and 2100Z in Bakersfield, CA. Despite being in what should have been a "hot start" mode, none achieved a GPS fix until 2200Z. The powerup time and time and position of first fix for the units were as follows:Powered at 2100Z ; fix at 220019Z N34-48 W116-58 near Barstow, CAPowered at 2045Z ; fix at 220025Z N35-16 W116-07 near Baker, CAPowered at 2104Z ; fix at 220048Z N34-41 W117-24 near Victorville, CAPowered at 2026Z ; fix at 221536Z N34-53 W115-11 near Goffs, CAThe fact that three units achieved a fix within 30 seconds of each other, while being separated geographically, and with varying (and excessive) times since startup, seemed unusual. The aircraft were all at an altitude of approximately 7000feet MSL.A fifth [equipment] was mistakenly left powered up throughout the ground stop at BFL, and logged a complete track. No other GPS anomalies were reported by participants. A [different model GPS unit] that was powered up at Bakersfield in the same timeframe acquired a fix immediately.I am aware that GPS interference testing was being conducted at Twentynine Palms that day (Flight Advisory 29PALMS 19-01), with the affected area encompassing the entire route of flight from Bakersfield to Laughlin. However, the testing was scheduled to be completed at 1300Z.While this issue is likely to be a manufacturer specific glitch, I am reporting it to see if any external factors may have been involved.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

Since the user acknowledged other equipment in the same aircraft operated normally, and we have no correlating information, NAVCEN encouraged the user to contact their equipment manufacturer for assistance. NAVCEN requested additional information and the user acknowledged the issue was their user equipment.

User Equipment06/03/201919905/15/2019Statesville, NCTransportationUser: Traveling East on I-40 about 7:30pm EST. GPS location [on mobile phone navigation application] started instantly changing directions 30 or 45 degrees, running off road for 1/4 to 1/2 mile, then rerouting. The area was being prepped for repaving and crews were setting up. The issue continued until we were about 10 miles east of Statesville (about 15 miles from start). It happened again at another construction area between Mocksville and Winston-Salem, also at a construction site. and a third time entering Winston Salem (again a construction- repaving site.) It happened one more time during the drive - about 9pm EST east of Burlington, NC near Mebane, also in a repaving zone. I am concerned that new equipment to help the repaving contractors is interfering with the GPS receivers.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer or application developer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer or application developer. The user did not respond to our request.

User Equipment05/24/201920005/15/2019Larnaca, CyprusMarineUser: This is now a daily occurrence in this area. Apart from losing a reliable position, I also lose the ability to lock the yacht to a predetermined route, and more importantly, collision alerting through my AIS B transponder and [software]. If I cannot broadcast my position, then the system ceases to function. This is a major concern as I sail single handed to Israel, the Lebanon, and to Turkey. AIS is my primary watch method when I inevitably have to rest. The outage is always confirmed through 3 receivers plus my GPS [mobile phone] app which is very useful in proving that this is not an equipment malfunction, but genuine interference or jamming. Other yachts at Larnaca also confirm the problem. I took a video of the satellite status page on my [manufacturer] GPS which I can send you once I have the correct email address to send it to. This summer I have not made any long trips so far, so I am unable to establish the area affected. Thank you for your concern. This has to be stopped before someone has an accident.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN requested any additional information, including communication authority response details. User responded that the problem has cleared. They will contact their equipment manufacturer and report the outage to the nearest communication authority.

Unknown Interference05/24/201919805/14/2019Hawthorne, CALaw EnforcementUser: For the past two days, our GPS receivers have been unable to obtain a GPS FIX in the area.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance. NAVCEN requested additional information, including any information from their equipment manufacturer. The user did not respond to our request.

User Equipment05/24/201919705/12/2019Port Said, EgyptMarineUser: While at anchorage near the entrance to the Suez Canal. The vessel [vessel name] ships staff started receiving a GPS failure alarm from their equipment.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN: This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN asked if the user had contacted their equipment manufacturer. Reporting source did not respond to the request for additional information.

Unknown Interference05/20/201919505/06/2019Mitchellville, MDUser: I drive a semi. GPS is out as well as my ELD.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User provided GPS screenshots that indicate no GPS received but no other information such as other devices with the same issue, or if the device has a clear view of the sky. User encouraged to contact their equipment manufacturer for assistance and asked to share manufacturer response with NAVCEN. User did not respond to request for additional information.

User Equipment05/15/201919605/06/2019Port Said, EgyptMarineUser: DGPS Error was the message displayed.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN: This report correlates with the U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. NAVCEN asked if the user had contacted their equipment manufacturer or DGPS service provider. The reporting source did not respond to the request for additional information.

Unknown Interference05/16/201922504/30/2019Magnolia TexasAutomobileClock display blank. All clock settings blank

NAVCEN: As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. Requested additional information, including any information from their equipment manufacturer but the reporting source did not respond.

User Equipment08/19/201919204/27/2019Damietta, EgyptMarineUser: Unable to acquire more than 2 sats, weak signal on sats acquired. 1 Additional GPS of same make and model with antenna located on other side of vessel is receiving normally.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. User did not respond to request for additional information.

Unknown Interference05/06/201919104/25/2019Port Said, EgyptUser: [Vessel] was effected by the repetitive loss of GPS signal, affecting radar, ais, and gyro input. [Vessel] location was the Port Said EGYPT anchorage. This occurred from 1800 24 April, thru 0330 25 April, while my ship and numerous other ships were attempting to transit the Suez Canal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area.

See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority. User did not respond to request for additional information.

Unknown Interference05/06/201919004/24/2019Departure Limassol, CyprusMarineUser: During navigation from Limassol, Cyprus to Haifa, Israel, both GPS (1&2) signals were lost. During early morning signal went back but both GPS are showing wrong date (09 September 1999).

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. User worked with their equipment manufacturer, replaced equipment, and the issue has resolved.

User Equipment04/30/201918804/22/2019Liege - Grace-HollogneTransportationI have been heading from Grace-Hollogne (Belgium) to Frankfurt am Main (Germany) in my truck and issue of GPS fix occur. These errors have I been noticed on my smartphone and on my car-mounted navigation. After 2hours and 34 minutes I havent noticed any GPS fix only assisted GPS "jumps" on my smartphone between signal points from my operator. On [navigation] device screen sometimes blink a "searching" icon but it gets any better. Now I am standing on parking place on highway and still havent my GPS signal uplink.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

User encouraged to report the issue to the Belgian Institute for Postal services and Telecommunications and the Federal Network Agency (Bundesnetzagentur) in Germany. User did not respond to request for additional information.

Unknown Interference05/06/201918604/15/2019Abilene, TXSurveyingUser: On 4/15/19 - We were calibrating our GPS equipment used to perform highway construction when we began having issues with the accuracy of the GPS. We considered this to be a calibration/file issue and ran multiple troubleshooting protocols to fix the issue, however, after many attempts to correct the problem we were unsuccessful and headed home for the night.

4/16/19 - We began working again the morning of the 16th to resolve the lingering issue. After setting up our GPS equipment the number of satellites began to drop until eventually our equipment was not tracking any satellites. We are in the vicinity of an aiport and an Air Force base. Prior to this incident we were using a different frequency equipment which we found was supposed to have issues with the frequencies being used at the AFB/Aiport. We changed our equipment to run on 900 mhz frequency to avoid any interference and the equipment was running as it should. Then we began having issues as listed above. We have had a certified troubleshooter of equipment on site and they are in agreement that there is some type of interference or jamming occurring.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

Interference appears to be at 900MHz. User encouraged to contact the FCC Jammer Tip Line to report the suspected interference. User did not respond to request for additional information.

Unknown Interference04/30/201918704/15/2019Abeokuta, NigeriaSurveyingUser: The GPS Receiver tracked fine. On downloading there are evidence of recording by the size of data acquired. On processing, the error is failed in single positioning. The coordinate is 0 for both Latitude and Longitude. This occur for different receivers and on many days.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance.

User did not respond to request for additional information.

User Equipment05/14/201918504/14/2019Warsaw, PolandTransportationUser: Since Sunday 16.04.2019 our devices have a problem with number of satellites in Poland. At the moment, more than a thousand devices can see only 2-3 satellites. Can you tell us where the problem is?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. Suspect GPS Week Number Rollover issue.

User acknowledged the issue is likely related to the GPS Week Number Rollover. They are working with their equipment manufacturer and expect a firmware update to correct the issue.

User Equipment04/24/201918304/09/2019Apuarema, BrazilSurveyingUser: "precisamos trabalhar e temos apenas esses aparelho,grato"

NAVCEN made several requests for additional information and received no response. As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance.

User Equipment05/14/201918404/07/2019Tehran, IranTransportationUser: It is something like a big noise. Since one week before all off car GPS modules involved. The problem is the date, location and clock is correct but date is 2099. today it is 29-8-2099. This strange mistake was reported from lots of cities in Iran.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance.

User did not respond to request for additional information.

User Equipment05/14/201918104/06/2019Fahud, OmanSurveyingUser: Our geophysical recording instruments was unable to get sufficient number of elevated GPS satellites intermittently on 6th April 2019 for time correction.Though we have communicated to our clients but it is necessary to get some information from GPS about disruption in this area. Kindly confirm.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. User did not respond to request for additional information.

User Equipment05/14/201918004/05/2019Oulu, FinlandCommunicationsUser: GPS Week Number Rollover expected on April 6th, 23:59 (GPS time). It appears GPS almanac changes were applied the day before affecting some GNSS equipment before the GPS WNRO. We were not prepared for the GPS WNRO prior to April 6th. Now we must hope that actual GPS week number rollover event will fix the situation. What changed and when did the changes happen?

NAVCEN: The U.S. Air Force points to Interface Specification IS-GPS-200, paragraph 20.3.3.5.2.2, Almanac Reference Time, which states: "The almanac reference time, t(oa), is some some multiple of 2(12) seconds occurring approximately 70 hours after the first valid transmission time for this almanac data set (reference 20.3.4.5). The almanac is updated often enough to ensure that GPS time, t, shall differ from t(oa) by less than 3.5 days during the transmission period." They go on to point out "For this reason, beginning late on JDay 094 [April 4th], the GPS constellation began, one satellite at a time, broadcasting almanacs with almanac reference times which, when un-truncated as necessary, translate(d) to a calendar date of 7 April 2019 (after the associated 1024-week rollover), correctly, and IAW IS-GPS-200."

User acknowledged the problem is related to the how their equipment is handling the GPS Week Number Rollover.

Additional user questions forwarded to interagency partners. Response to user questions provided to the user. The user has not requested additional information.

User Equipment06/03/201917904/04/2019United StatesCommunicationsAt roughly 8:45 PM CST lost GPS Sync to various cell sites around the US. The common GPS is trend is dual cones feeding sync to UMTS and LTE technologies. To mitigate the issue Field Technicians have removed one of the GPS cones and have a master sync from LTE feeding UMTS. There was no back office or architectural changes to our network during this time that would have caused this failure. We are curious if there were any changes made in preparation of the GPS System rollover slated for tomorrow April 6th that may have affected the base stations to lose sync.

NAVCEN: The U.S. Air Force points to Interface Specification IS-GPS-200, paragraph 20.3.3.5.2.2, Almanac Reference Time, which states: "The almanac reference time, t(oa), is some some multiple of 2(12) seconds occurring approximately 70 hours after the first valid transmission time for this almanac data set (reference 20.3.4.5). The almanac is updated often enough to ensure that GPS time, t, shall differ from t(oa) by less than 3.5 days during the transmission period." They go on to point out "For this reason, beginning late on JDay 094 [April 4th], the GPS constellation began, one satellite at a time, broadcasting almanacs with almanac reference times which, when un-truncated as necessary, translate(d) to a calendar date of 7 April 2019 (after the associated 1024-week rollover), correctly, and IAW IS-GPS-200."

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. User did not respond to requests for additional information.

User Equipment05/14/201917803/28/2019None providedUser: WE are a business that has been in the same location for over 20 years yet, GPS/MAP QUEST cannot seem to locate. It sends our clients to other locations across town.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue04/24/201917603/19/2019Pireaus, GreeceOtherUser: GPS signal lost has been report by other vessels in the vicinity.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

User encouraged to report the issue to the Hellenic Telecommunications and Post Commission.

Unknown Interference04/16/201917503/18/2019Madrid, SpainOtherUser: At 10:29PM UTC+1 03/18/2019 we have detected alarms in a lot of GPS of our network. We saw GPS with more than 10 satellites when in most cases have 6 or 7 satellites. Could you check if you detected any incidence at this time?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

User encouraged to report the issue to the Comisión Nacional de los Mercados y la Competencia.

Unknown Interference04/16/201917403/14/2019Redmond, WAOtherUser: multiple days observed a disruption in the morning hours in this vicinity. .GPX file is available. I run this area often and only see it in the morning.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN forwarded user data to the Federal Communications Commission Operations Center. FCC pointed out "it was likely that the [user device] was influenced from natural effects such as tall buildings and dense tree in that area. These factors (heavy foliage and tall buildings) reduce or completely block GPS satellite signals. In addition, many tall buildings in that described area also created a multi-path so that GPS signals bounce off buildings before it reaches the [user device]."

User Equipment05/14/201917203/07/2019Dongguan, ChinaMarineUser: All GPS above lost position at the same time. Captain confirmed that his AIS showing China flags vessels only – probably they are using Chinese positioning system BeiDou

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

User encouraged to report the interference to the nearest communication authority.

Unknown Interference04/16/201919303/01/2019Tripoli, LebanonSurveyingUser: we tried to relocate receiver and Antenna to another town but same performance (no GPS and having 7 to 10 GLONASS) we had another stations covering whole Lebanon and working fine

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User equipment suspected. User encouraged to contact their equipment manufacturer for assistance. User did not respond to request for additional information.

User Equipment05/08/201916902/13/2019Beirut, LebanonMarineUser: The problem started at 13.02.19 / 0326 UTC , but at 0512 UTC the connection was restored till 0858 UTC. From this time the interference is continuously till present with a few times for only a few minutes no interference.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

See U.S. Maritime Advisory 2018-014-Eastern Mediterranean Sea-GPS Interference on the MSCI Portal

User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201916802/09/2019Hodeidah, YemenMarineUser: VESSEL LOST SIGNAL FOR A PERIOD OF 10 MINUTES. AT 0200 LT FULL DGPS SIGNAL RESUMED WITH NORMAL FUNCTIONALITY. I DID NOT NOTE WHICH SATELLITES WERE BEING TRACKED.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

See U.S. Maritime Advisory 2018-014-Eastern Mediterranean Sea-GPS Interference on the MSCI Portal

User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201921802/01/2019GlobalSurveyingUser: Thanks to Navigation and Timing Monitoring Facility. Since the begining of February we received several NANU reporting unscheduled outages of a few minutes for some GPS satellites. NANU 2019020, 2019026, 2019085, 2019086, 2019091, 2019093, and 2019095. For each NANU we analyzed rinex navigation and measurement files from stations in visibility of the satellites. In every case the satellites were healthy according to their broadcast ephemeris data. We never saw any measurement gap bias or drift that could be linked to a clock problem and we could not see any power drop. When the satellites were monitored by a SBAS we did not see any problem with the satellites. Could you confirm the nature of the outage and the impact on the receivers? We would like to know our receivers behaved. As for the SBAS it is important to know if they have sent correct information. SBAS users could have used the satellites despite the outages and it could have led to a potentially hazardous situation. If you need additional information concerning our analysis please feel free to contact us.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment and determined it to be healthy, stable and robust during that time. It continues to provide precise positioning navigation and timing information to military and civilian users around the world.

NANU in question were sent as a precautionary measure. Information that was received from these satellites was still accurate.

None07/22/201917001/11/2019United StatesSurveyingUser: Observation of GPS NANU times in relation to the time satellites are set to unhealthy do not match past NANUs and satellite status. What time should be used? The time listed in the NANU, or the time the satellite was set unhealthy?

NAVCEN: The GPS Operations Center provided the following response: In reference to your question, no maintenance activities were initiated prior to the SVs being set UNHEALTHY. Moving forward, the GPS Master Control Station will work to ensure the NANU more closely tracks the exact time the SVs are set UNHEALTHY to avoid misconceptions. Again, thank you for bringing this matter to our attention.

Other05/07/201916312/04/2018Denver, COResearchUser: For the past several days I have been picking up PRN 4 (which does not exist AFAIK) intermittently, always with no elevation or azimuth in the NMEA (because not in atlas I would guess). Duration from a 1s to 1.5h, starting around 0600MST and stopping around 2000MST.

NAVCEN: PRN4 is being used to test SVN36. This testing was published in NANU 2018042. "ON APPROXIMATELY 10 OCT 2018 SVN36 WILL RESUME TRANSMITTING L-BAND UTILIZING PRN04. AT L-BAND ACTIVATION, SVN36/PRN04 WILL BE UNUSABLE UNTIL FURTHER NOTICE. ADDITIONALLY, NO BROADCAST ALMANACS WILL INCLUDE SVN36/PRN04 UNTIL FURTHER NOTICE."

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/07/201916111/18/2018Hadera, IsraelMarineUser provided no description of their problem.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

See U.S. Maritime Advisory 2018-014A-GPS Interference-Eastern Mediterranean and Red Seas for further information on this interference. MSCI Portal

User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201916011/17/2018Straits of TiranMarineUser: While on route toward Aqaba, Jordan, the vessel experience 03 incidents of loss GPS signal in the straits of Tiran. These 03 incidents lasted approx. 10 mins each. Event occurred between 0245-0440UTC.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201916711/15/2018Washington StateTimingUser: Ongoing GPS failures since December 2017 at several sites. Was curious if other entities have reported outages in this area. Running redundant receivers and antennas at equipment sites. Technicians report different manufacturer equipment would fail at different times of the day. One timing receiver is experiencing more failures. Equipment alarms and requires manual reset to lock back on to GPS signal. Just really hard for me to think it is an equipment problem while three of them at different locations are doing this same thing.

NAVCEN: Equipment alarm records provided by the reporting source indicate similar errors across several timing units used by the reporting source and appear to be typical for this equipment. Errors were momentary (less than one second) with an average of approximately 90 momentary errors per site over the course of a year. Some equipment initiated more alarms, but there seemed to be no correlation between times, locations, or types of alarms. Redundant antenna and receiver systems did not alarm at the same time. The reporting source contacted their equipment manufacturer who identified a firmware issue. Reporting source now believes the problems are equipment issues and will provide more information if it becomes available.

The GPS Operations Center reviewed the GPS Constellation and Control Segment; there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. Coast Guard-operated Differential GPS did NOT observe GPS problems during 2018.

User Equipment05/07/201915811/11/2018Usuda (Japan), Maui (Hawai - USA) ...OtherUser: On the 11th and 12th of November 2018, the IODCs of the ephemeris/clock information transmitted by PRN32 from 11:33:30 (11 Nov) to 02:00:00 (12 Nov) were the same as the ones used on the 10th of November from 11:27:30 to 22:00:00 while the navigation data were different, in violation of the GPS ICD 200 IODC repetition rule (unicity over 7 days).

NAVCEN: Response from GPS Operations Center: The cause of the IODC repetition error was the result of an issue experienced with the ground control system. The problem has been corrected.

ICD_Violation05/08/201915711/10/2018Evansville, INFirst ResponderUser: On 22 October the units began reporting a date of 11 March 1999. Time is correct, date is off.

NAVCEN: The GPS week number for both dates are the same (1000). User encouraged to contact their equipment manufacturer for assistance.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/08/201915911/10/2018North SeaMarineUser: 17 Seconds before midnight on 10.11.2018 vessel experienced date jump. After midnight date changed again. Information collected with ZDA NMEA Sentence and wrong date were observed for approximately 24 hours until date changed back to actual date.

NAVCEN: Appears the GPS equipment incorrectly handling the GPS Week Number. Recommend user contact the equipment manufacturer for further assistance.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/08/201915511/04/201835 - 04.4N, 034 - 48.1EMarineUser: We have encountered more severe than normal GPS interference tonight. Shortly after 1800 local we lost all 3 GPS units, 2 for navigation, and the third within the AIS unit. Wanted to keep you appraised as again this is the most severe case yet. Certainly seems like a beam has hit this area. Thanks and will let you know once it clears some, or if it doesnt by the time we get to our destination. Thank goodness for paper charts.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/08/201915411/01/2018Haifa Port, IsraelMarineUser: Erratic GPS signal reception.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/08/201916211/01/2018Raleigh-Durham, NCSurveyingUser: The unit has ceased to display valid date and time information and reverted to the year 1999 without a reliable calendar day or clock time. This affects time/date of lunar and solar positions that were used for estimating positioning and also other conveniences such as sunset/sunrise. The date and time can be obtained from other sources that the handheld GPS easily. I contacted the manufacturer who denied any manufacturing defects and could not offer a solution except to obtain another device at my expense (out of warranty for several years). This is only reported for general information or recall, no response or solution is necessary unless there is a widespread recall or other issue that I am not aware of. Thru the last weeks even though the time/date was off the two dimensional lat/long have proven precise and the elevation above sea level continues to experience fluctuations as previously reported.(date/time of problem onset is estimated)

NAVCEN: There are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

The GPS Week Number advanced to 1000 on 22 October 2018. GPS Week Number in March 1999 was also 1000. User encouraged to contact their equipment manufacturer for assistance as it appears the GPS equipment is incorrectly handling the GPS Week Number.

User Equipment05/07/201915310/29/2018Strait of HormuzMarineUser: This vessel possesses two GPS units of the same make and model. Both units intermittently lost signal during the listed time period. The units regained signal by themselves in under 30 seconds after disruption. The incident occurred during a westbound transit of the Strait of Hormuz into the Persian Gulf. The last observed disruption occurred in the vicinity of 25-30N; 054-03E. The number of satellites (And the satellites in use) was not recorded during the period of disruption. Currently, both GPS units register 31 satellites and are obtaining a position via the following eight: 20, 21, 29, 10, 15, 26, 16, and 25. The vessel is still in the Persian Gulf as of writing this report. A contracted service company believes a military base in the area was jamming the GPS signal. The Iranian military scheduled gunnery exercises in the Strait of Hormuz on the 29th and 30th.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User encouraged to report the issue to the Communications Regulatory Authority of Iran.

Unknown Interference05/08/201915110/22/2018Fort Collins, COTimingUser: Our devices experiencing fluctuation in GPS PPS nationwide. It is not restricted to one area or GPS model. Our tools rely on GPS PPS synchronization with 60 Hz power grid. Working devices all suddently failing starting 10/22/2018. Please advise!

NAVCEN: It appears the equipment is incorrectly handling the GPS Week Number. The GPS week number for both dates are the same (1000). User encouraged to contact their equipment manufacturer for assistance.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/08/201915210/21/2018Santorini, GreeceMarineUser: Ii is 7days that probably all [equipment] fishfinders do not synchronize date and time. All users experience the same malfunction. Please advise

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to report the issue to their equipment manufacturer and the Hellenic Telecommunications and Post Commission.

User Equipment05/08/201914810/16/2018Leesburg, VATransportationUser: At approximately this time +/- 10 minutes the unit (a high end bike computer w/ normal GPS accuracy of 9 feet) reported a -64% grade rather than the real of -1 to -3%. It also reported loss of GPS lock. It was actively searching for a lock which it had lost. Its estimated accuracy at the time was approximately 274 feet. The problem continued across a power boot of the unit. The problem resolved within about 5-10 minutes, achieving a lock with 9 foot accuracy.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance.

User Equipment05/08/201914710/15/2018Jeddah Port, Saudi ArabiaMarineUser: We lost the GPS Signal on all nodes while we are approaching the Jeddah Port today 15/10/2018, 0530z. Checked with the out bound vessels and they too does not have GPS Signals. Believed it has been jammed. Had confirmed with the departure ship [vessel] that they too have the same problem, but they received the GPS Signal once they are about 8 miles from the Port. Had checked with incoming ship [vessel] that they too lost the signals once reached the approaching area. Based on these two facts, conclusion is that it is localised to this port area only. When our Vessel is cleared of Jeddah Port and 7 miles away, GPS signal is back on all GPS receivers, GMDSS, SSAS,FBB etc,. Same as other ships have shared the information earlier. Best regards, Captain. Thank you.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space weather was reviewed and found likely to have impacted GPS performance. No correlating reports from other users or interagency partners.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal.

User encouraged to report the issue to the Communications and Information Technology Commission of the Kingdom of Saudi Arabia.

Unknown Interference05/08/201914910/13/2018Jeddah Port, Saudi ArabiaMarineUser: Before Departure from port of Jeddah Saudi Arabia in Red Sea both GPS were found out of order. There seemed to be GPS signal interference resulting in loss of signal, missing COG / SOG and absence of GPS signals affecting bridge navigation and other communication equipment. GPS screen showing no available satellites in the vicinity, no Lat/Long could be obtained. GPSs restarted - no effect. Pilot advised that tugs reported absence of GPS signal as well. After vessel was cast off situation remained unchanged so own position was obtained by visual and radar observations and frequently plotted in ECDIS as manual fix position. ECDIS was turned to Dead Reckoning mode. Approximately 10 nm away from port area both GPS recovered the signal. After calling few nearby vessels by VHF found out that GPS signal loss problem was common in this area. Also experienced that on private smartphones (verified by Master and 2/Off) it was impossible to obtain GPS position, the signal was not available.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space weather was reviewed and found likely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to report the issue to the Communications and Information Technology Commission of the Kingdom of Saudi Arabia.

Unknown Interference05/08/201914510/08/2018Rochester, NYTimingUser: Two large phase events occurred between 0430 and 0445 UTC on October 8th.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/07/201914610/08/2018Huddersfield, UKCommunicationsUser: Loss of GPS lock for approx. 4 minutes during visibility of PRN27. Issue ongoing. Receivers manually forced to holdover mode until advised otherwise. Request further details of actual issue affecting PRN27 for fault reporting purposes please.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance.

User Equipment05/08/201914310/01/2018Port Said, EgyptMarineUser: Report received by email from the [vessel]. "While making the approach to Port Said, at 0030 thru 0215 and 0220 thru 0400 on 30 October we lost all GPS signal, with no fix during this time line. While at Port Said anchorage 31-22.8N, 032-20.1E), we lost GPS due to interference from 1930 thru 2040 on 30 October 2018. We had no impact to navigation while at anchor. Departure from anchorage and Suez Canal transit had no issues with GPS.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage.

See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201914209/27/2018Plymouth, UKMarineUser: The intermittent fault happened several times while going East across Bigbury Bay -where I have had block problems before - the system started again near Thurlestone and continued to work back to Plymouth except that the interval report along the route were not applied for about an hour. Past route can be seen on Marine Traffic - boat name [removed]

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Recommend user contact the UK Office of Communications. Report forwarded to the UK Centre for the Protection of National Infrastructure.

Unknown Interference05/07/201914109/11/2018KabulCommunicationsUser: On 11th Sept Approx, Kabul Meteorological Department reported they were unable to track weather balloons. KABUL ATC GPS clock and navigation systems and other users were unable to gain GPS lock. Incoming aircraft report losing GPS at approx 6 miles from the airport on approach, but regain on departure.Used a spectrum analyzer and detected no apparent interference, jamming, or particular transmission from any direction from middle of the airport between runway and taxiway.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Recommend user contact the Afghanistan Telecom Regulatory Authority for Assistance.

Unknown Interference05/07/201913909/07/2018Bratislava, SlovakiaAutomobileUser: Two different GPS tracking modules placed outside window cannot find GPS signal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201913809/06/2018Gulf of MexicoMarineUser: Multiple vessels in our area experienced degradation of GPS signal resulting in elevated PDOP. GLONASS systems were unaffected.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, they informed us that due to the current GPS constellation there is abnormally high DOP in the Gulf of Mexico. It is only for a short time.

Additionally, there was an authorized GPS test in the vicinity at the date of the report. NOAA reported impacts to their equipment in the area. No other correlating reports from other users or interagency partner.

GPS Testing05/07/201914008/29/2018Tehran, IranCommunicationsUser: Hi I find out that in all of the tehran we have td-lte GPS clock synchronization problem That most of the this type of internet service can not access to internet And also cant use [mapping application] and other GPS based application So please tell us Is this another sanction or not?!? Regards

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment05/07/201913708/20/2018San Bernardino, CATransportationUser: GPS diagnostic screen on [equipment] showing two Satellites with no lock. With an accuracy of greater than 1200 ft. [equipment] showing 0 of 10 satellites tracked with no lock. [equipment] showing zero us satellites but showing 8 GLONASS satellites with lock. Strength average about 28 per GPS data app. Has been occurring across 2 days started in Barstow California satellite loss on GPS navigation unit has been occurring off and on across the 21st and across an area from City of Industry to San Bernardino California. GPS randomly receive signal from satellites number 10, 15, 16, 20, 21, 26, 27, and 29. Lock varies from Full to non-existent. Same as occurring on mobile phone and [equipment] Eld. Power cycle of all devices and downloading a GPS data for cell phone did not correct.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201919408/15/2018Plovdiv, BulgariaTransportationUser: From August last year the clock in almost all [vehicle type] with original navigation are showing wrong date, the year is 1999 the daylight saving time is incorrect due to months mismatch, but the time is correct just 1 hour backward, it now shows November 1999 or something. This problem is massive a lot of people are complaining. Please tell me what happened from August last year so old receivers decode date and year wrong, but newer are alright.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. Suspect GPS Week Number Rollover issue.

As the GPS Week Number Rollover may have been a factor, user encouraged to contact their equipment manufacturer for assistance. User acknowledged the issue is likely related to the GPS Week Number Rollover and their older navigation system.

User Equipment05/08/201913508/11/201850 miles from Qingdao, ChinaMarineUser: Military/navy exercises being conducted south of our position. Disruption at intervals for the last 50 mins. Receiver use: Input to nav equipment, communications. Vessel at anchor.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201913608/10/2018Scottsdale, AZOtherUser: Testing mixed mode tracking Y-code and M-code, up to the time specified, tracking L1 and L2 M-code for PRN 26. Receiver lost lock on the L1 channel, L2 continued to track. Could track C/A, but not L1 for PRN 26 for the duration the SV remained in view. Observed other SVs with similar behavior at different times over a 3 day test period. Trying to understand why we lose lock on L1 but not L2.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/07/201913408/03/2018Avon, INOtherUser: My son wears a GPS watch due to the possibility of him wandering from school. Around 11:30 today, I received a “check in” notification that he was in Upland, IN. I called the school in Avon, IN (hours from Upland) and they confirmed he was in class.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/07/201914408/01/2018Lakewood, WATransportationUser: For many months now, GPS goes off track when directly north of McChord Field on I-5.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/07/201913307/23/2018Port Said, EgyptMarineUser: The [vessel] was moored in Port Said Egypt when the captain informed me that he lost the primary and secondary GPS. Disruption was intermittent. GPS also showed the ships location of west of Alexandria on at least one occasion. Ships contact information: [removed]. Please feel free to contact me or the ship directly if you have any questions.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201913107/04/2018Port Said, EgyptMarineVessel was at anchor in Port Said, Egypt awaiting a canal transit on the GPS units started alarming with NO GPS FIX alarms. We verified our position using our anchor range and bearings & manually fixing position on ECDIS. Other vessels in area are reporting GPS problems as well.

See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference.

Unknown Interference11/14/201813207/04/2018Port Said, EgyptMarineUser: Vessel at anchor in Port Said, Egypt. GPS units started alarming with NO GPS FIX alarms. Position verified using anchor range and bearings & manually fixing position on ECDIS. Other vessels in area are reporting GPS problems as well. GPS interference continued intermittently throughout the entire day.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201912706/28/2018Ankara, TurkeyOtherUser: I am developing a product based on [equipment], which uses [chipset]. I was not getting a valid fix since the morning (now is 16:00 local time). I have tried to get a fix with my cell and couldnt get a valid fix for a long time. The phone has seen just one satellite and it had a very weak SNR.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment05/07/201912806/28/2018Rockport, Texas User: The problem are the directions given to truckers, etc, when attempting to visit our facility. Directions send the vehicles to the south side of the ship channel. Our facility is on the north side of the ship channel.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/08/201912506/16/2018Vila do Conde, BrazilMarineUser: Every day in the morning time up to lunch time the GPS gives warnings about unsafe position.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201912406/15/2018Nashville, TNOtherUser: Mapping applications on three devices gave the wrong directions three times. None of the maps were anywhere correct. Was there a disruption or outage? Might not be anything but it was very odd. Also, the application seemed to be speaking jabberwocky at times during the ordeal of us being lost.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner.

User Equipment05/07/201912606/15/2018Powell, OHTransportationUser: I pulled up GPS on my [mobile phone] to get a route. I used [mapping application] first and it said that no GPS was available at that time. I then tried [mapping application] and it was down too. I closed down both apps and tried shutting down my phone and still, nothing worked. I ended up finding turn by turn directions that did not use GPS. I used those but got into a car accident because as a new driver, I rely on GPS. When law enforcement (EMS and police) arrived on the scene, I told them that GPS was down. They said that their systems were down too. Were there any planned outages in our area around that time? If so, I wish that I had been warned somehow and saved from that dangerous situation. Many people rely on GPS in order to safely navigate, and an outage can cause accidents and even deaths.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User Equipment05/07/201912005/29/2018Le Port Reunion IslandSurveyingUser: GPS elevation inaccuracy greater than 10 cm between 1400 and 1430 and then from 1800 local time (UT+4). It is affecting about 10 or more receivers on site (all machines, survey boat, land GPS backpack, excavators) we are working with RTK mobile receiver link to a base station by radio ling. There are three RTK base station on site with dedicated radio link. We saw on the sky GPS predictions. That GPS N29, is in view between about 1700 and 1430 then coming back again from about 1800 (5 degree elevation mask). We will try to disable GPS N29 from our equipment. No further information provided.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment05/07/201911905/27/2018Bend, OregonAutomobileUser: Getting a NO GPS symbol on our unit, tried resetting and powering on and off, no swings have changed since last use.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance.

User Equipment05/08/201912305/26/2018Yellowknife, CanadaOtherUser: PRN18 failed to be measured near the period of an unusable (UNUNOREF) NANU covering part of the reported period. NANU 2018028-GPS SATELLITE SVN34(PRN18)WAS UNUSABLE ON JDAY 146 (26 MAY 2018) BEGINNING 0948 ZULU UNTIL JDAY 146 (26 MAY 2018) ENDING 0950 ZULU. IGS observations covered 0940-0948.

NAVCEN: Report forwarded to GPSOC. Issue was covered by the release of NANU 2018028.

None05/07/201911705/18/201835 NM North of Egyptian coast MarineUser: GPS total signal loss on 3 occasions: 17MAY18 2354Z - 18MAY18 0031Z 18MAY18 0240Z - 0248Z 0340Z - 0341Z -[equipment] models track Cypress standard GPS with Differential beacon 320 - [equipment] models track a Differential spot beam service by paid subscription. Last noted GPS interruption was on 30 APR

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201911805/18/2018100NM off Port SaidMarineUser: For the past hour GPS signal is either lost or incorrect in approximately 5 minute increments. Vessels in the area are reporting the same.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201911505/10/2018Port Said, EgyptMarineUser: [Vessel] Tracking 85 East. Vessel is located in port, position keeps changing even though vessel is not moving. position is wrong in about 2-2.5hr increments; incorrect positions are not consistent.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201912105/10/2018Fairbanks, AlaskaOtherUser: Since 10 May, several balloon flights have been terminated due to possible GPS interference issues. Analysis points to a possible disturbance source of narrow beam transmission from the airport or in its vicinity.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There was an authorized GPS tests in the vicinity at the date and time of the report. No correlating reports from other users or interagency partner.

GPS Testing05/08/201911405/09/2018Armenia, Quindio, ColumbiaOtherUser: All my phones, my friends phones, and tablets are currently experiencing this outage in Armenis, Quindio, Colombia.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201912205/01/2018Doylestown, PennsylvaniaCommunicationsUser: Indicated location was erratic and device was unable to obtain accurate GPS location even after device was reset after traveling 5 miles. Device works normally in other locations throughout the U.S.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/07/201911304/30/2018Orlando, FloridaAviationUser: [Our company] is a producer of high accuracy, aviation time, space, and position information (TSPI) equipment, primarily for defense. We develop, produce, and maintain TSPI equipment at the coordinates above. We have been experiencing nearly continuous interference over the past two days. The interfering transmitter is operating in the range approximately 1566-1576 MHz. The signal is a modulated signal and appears to be an out of band transmitter as opposed to a jammer. We have captured the spectra at several times. The interfering system is blanking our (and presumably other) receivers. We are well versed in GNSS systems and technology. The equipment being blanked is used in military flight test operations. The ongoing interference is impacting our ability to conduct operations. Please do not hesitate to contact me should you have any questions or need any additional information.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partner. Report forwarded to FCC for action.

Unknown Interference05/07/201911204/23/2018Colorado Springs, COUser: Going north on I-25 around Colorado Springs, CO., GPS insisted that I get off of I-25 at each exit instead of waiting for correct exit. It occurred entering and departing Colorado Springs, CO. area.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/07/201910904/18/2018EASTERN MEDITERRANEAN SEAMarineUser: DISRUPTIONS EVERY FEW MINUTES, CONTINUING AT TIME OF NOTIFICATION. ALL VESSELS IN THE AREA ARE COMPLAINING ABOUT THIS ISSUE. NO GPS POSITION FROM MORE THAN 3HRS. SATELLITES ARE TRACKED AND DECLARED HEALTHY IN GPS RECEIVER BUT NO POSITION AVAILABLE. PLEASE ASSIST ACCORDINGLY.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201911004/17/2018Romania and VietnamMarineUser: We have received reports from a shipyard in Romania and Vietnam having lost of GPS at a specific time of the day. In Romania, happens every day at 11:00 AM during about 5 minutes and in Vietnam happens at 3:00 AM or 1:30 PM depending of the position of the vessel. We would like to confirm that there are no known test/trials happening in this area at that specific time.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners. Recommended contacting the National Authority for Management and Regulation in Communications.

Unknown Interference05/07/201910804/16/2018Port Said, Egypt, N entrance of Suez Canal MarineUser: Intermittent and very frequent loss of GPS signal (time and position) while vessel was approaching Port Said). Same was reported by many vessels in vicinity by VHF radio.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201915603/29/2018York, PAOtherUser: My cell phone GPS does not function properly. I have gotten a new phone from the manufacturer which did not solve the problem. I have been speaking with my service provider and they are informing me that it is not a service issue but rather "my signal is being sent to the wrong satellite" and that they were unable to help me. They provided me with this link to file a report. I have used several different GPS apps, none of which work properly. Even when I am stationary these applications have difficulty finding my exact location and instead cast a large circle around my relative location. This has been going on for several months. It seems to be worse in more densely populated areas though it does not function well anywhere. Any assistance would be greatly appreciated.

NAVCEN: There are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact equipment manufacturer or application developer for further assistance. Most likely caused by incorrect equipment or application settings.

User Equipment05/08/201910403/22/2018DAMIETTA PORT, EgyptUser: GPS EXPERIENCES LOSS OF SIGNAL PROBLEM FROM LAST 5 DAYS. MOST OF THE TIME IT HAPPENS NEAR EGYPT, LEBANON AND IN EASTERN MEDITERRANEAN REGION.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201910203/21/2018SuezMarineUser: Vessel is West bound from Port Said to Gibraltar. Position stated is current one, problem with GPS position started in Port Suez on 21 March. This is ocean going ship with 3 GPS units (all same model) with no prior problems. Overheard on VHF other vessels experiencing GPS position issues. Can you confirm if the area is affected by malfunction, testing or other disruptions of GPS system? I suspected hardware problem, but it happens on ALL units and position is on and off. Thank you.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201910303/21/2018AT SEA, POST DEP PORT SAID, EgyptMarineUser: Master deemed it necessary to send it as non-routine under "any other potential, including potential problems" as the matter concerns vessels primary navigational system. Note that vessel had experienced problems with both GPS units of "no signal, alarm 001" since the night of 21st mar 2018. The problem of "no signal, alarm 001" was experienced on both GPSs just after departing from Suez Canal, Port Said side, on 21st Mar 2018. The problem was very frequently experienced in 3/O & 2/O watches. Then intermittently in C/Os watch going into the morning 22nd Mar 2018. Pls note that we had called at least 4 ships in our vicinity and they all confirmed the same problem with their GPSs, though with varying frequencies. This of-course has had an effect on the ECDIS. When the signals were lost, the courses went haywire. ARPAs was also effected, positions were not showing up.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/201910003/19/2018CyprusMarineUser: Sir/Madam, [we] have received information from multiple sources indicating a problem in receiving GPS signals on their equipment or having an accuracy problem., while sailing in the eastern Mediterranean. Could you please provide any information regarding this problem so the [we] can promulgate relative messages in case necessary? Best regards,

See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/20199803/18/2018Port Said, EgyptMarineUser: We have 4 DGPS and 3 GPS receivers on board. All of them affected. GPS were lost and DGPSs are being affected with not stable position or lost. Disturbance still continuous.

NAVCEN: See U.S. Maritime Advisory concerning GPS Interference on the MSCI Portal. User encouraged to report the issue to the nearest communication authority.

Unknown Interference05/07/20199603/07/2018San Francisco, CaliforniaAutomobileUser: Since 5am 7th March we noticed that the L1 frequency has been marked unhealthy in the CNAV ephemeris message. This is still continuing at 5pm on the same day. All L2 CNAV ephemeris message indicate that the L1 is unhealthy. Additionally L5 is marked unhealthy however this was the case before 5am today as well.

NAVCEN: The L2C and L5 signals are considered pre-operational. A pre-operational signal means the availability and other characteristics of the broadcast signal may not comply with all requirements of the relevant interface specifications and should be employed at the users own risk. Refer to Notice Advisory to NAVSTAR Users (NANU) 2014038 and 2014039.

User Equipment05/07/20199402/19/2018Washington (USA), Yellowknife (Canada), Brest (France) OtherUser: On the 19th of February 2018, some IODE/IODC of the ephemeris/clock information transmitted by PRN#06 from 04:42:30 to 06:44:30 were the same (14,15) as the data used on the same day for that PRN from 03:53:00 to 04:42:30 while the navigation data were different in violation of the GPS ICD 200 IODE repetition rule (unicity over 6 hours) and of the GPS ICD 200 IODC repetition rule (unicity over 7 days).

NAVCEN: Forwarded the report to the GPS Operations Center: The cause of the IODC repetition error was the result of an issue experienced with the ground control system. The problem has been corrected.

ICD_Violation05/07/20199302/16/2018West Palm, FloridaMarineUser provided no details related to their issue of their issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment05/07/20199201/31/2018Bad Pyrmont, GermanyTimingUser: This morning I was contacted by my [colleagues] who both have observed an anomaly in the timing characteristics of the GPS signal. [Colleague]s GPS receiver did an internal measurement against a Rubidium unit coupled with a very long time constant showed a time drift of -45ns an then back to zero whereas [colleague] is measuring the GPS offsets agains its internal HQ OCXO showed a time drift of +150ns and then back to zero. Both have used different types of receivers, [colleague] was using a [equipment] design with our proprietary receiver technology where [colleague] used the [equipment]. Is there a known anomaly in the GPS signal on Jan 31th between 7.00 and 8.00 UTC ? We have checked the number of received satellites and have found no outage. Best regards,

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

Unknown Interference05/07/201916501/15/2018Austin, TXAutomobileUser: In post-processing of the L2C CNAV message, it was observed that ephemeris records for several SVs were in error. Specifically, Longitude of the Ascending Node and/or Mean Anomaly differed by 1 semi-circle (PI radians) as compared to LNAV ephemeris, on some SVs. We understand L2C is pre-operational; informing in the unlikely case this error had yet to be diagnosed.

Follow-up from user: Please disregard a problem report submitted earlier suggesting an issue w/ GPS L2C ephemeris at the period specified. Suspected issue was found to be with the receiver.

Closed as user equipment issue.

User Equipment05/07/20199101/08/2018Hinkley,CaliforniaAutomobileUser: Heading East on highway 58, near Hinkley, CA, the GPS in the navigation suddenly announced "off route and recalculating", when the map restored, it showed the vehicle to the north of highway 58. Over 5 miles it slowly moved back until it showed us back on the highway. we checked both our cell phones and they showed the same error. On our return trip on Jan. 16, the same error occurred going west on highway 58 also just west of Hinkley.

NAVCEN: No correlating reports from other users or interagency partners. User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/07/20199901/01/2018Southern TasmaniaMarineUser: Numerous high HDOP errors frequently occurring over previous 3 months. Our unit is set to alarm at HDOP>2.0, and the alarm has been sounding numerous times each day. Vessel operating in southern Tasmania region, within a 200 mile radius of the position given above. Occasional very high spike into HDOP>30, and 2 occurrences >100, with subsequent position shift of around 200 metres noticed on ECDIS. Backup GPS receiver also shows occasional high DOP error (not split into HDOP and VDOP), but not as high as main unit. Is this likely to be a receiver fault?

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment05/07/201926801/01/2018Breckenridge, COAutomobileUSER: I was hoping to find out what GPS satellite was assigned to my vehicle for GPS. Has it been decommissioned or not updated? I cannot get any satisfaction from dealer. Confusing because I still have compass function and time, but date will always correspond to day and date in 2015. Seems it has not been updated since then and I am frustrated by that.

NAVCEN: There is no activity in the GPS constellation of satellites that could be causing the problem indicated. GPS equipment is not assigned a specific satellite. Rather the equipment will track all satellites in view, usually 8-12 of them depending on location. However, given this type of date time problem and the subsequent failure of your equipment, there is a high probability that your equipment was affected by the 2019 GPS rollover event. If your equipment is showing a date other than todays date, this is a problem with how your equipment is handling the updated GPS week number value. We recommend you ensure your equipment software is up to date, refer to your equipment manual, update your application, or contact your application developer or equipment manufacturer for assistance. We recommend all users share these reports with their application developer or equipment manufacturer. This real world feedback can help developers and manufacturers improve their products.

Update: Manufacturer has stated the user must replace the equipment.

User Equipment12/20/20198712/12/2017West Chester, PATransportationUser: Unable to acquire satellites even after restarting unit.

NAVCEN: User encouraged to contact their equipment manufacturer for further assistance. User later reported a software update corrected the issue.

User Equipment05/20/20198812/02/2017New York City, New YorkTimingUser: We have two receivers using separate antennas located on the west side of the building. The loss of timing happens ~4 minutes earlier every day. Problem started on 2 Dec at 1402 Eastern and last interruption was 30 Dec 1210 Eastern. Only recently started to log sats but it seems to happen when sat 12 is starting to be used by the receiver. This setup has been in use for >5 years with out coverage issue so I dont think that is the problem. We stay locked with 3 sats in view and this problem occurs with more than 3 sats. Confirmed there is no in band RF interference. We would appreciate any information since we are at a loss as what to do to remedy or mitigate this issue.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners. User informed the issue is most likely related to the location of the equipment and equipment settings.

User Equipment05/20/20198511/30/2017GlobalOtherUser: GPS PRN22 orbit error started to wander off. Problem seen globally, but worst on USA East Coast and East Australia. We would like to understand the reason for the anomaly.

NAVCEN: The GPS Operations Center reported PRN 22 was healthy and performing nominally. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20198411/19/2017Concord, CAOtherUser: Mobile phone GPS application unable to locate user. Device reset corrected the problem. User Equipment05/20/20198211/07/2017Worth, NYCommunicationsUser: Mobile phone has not been able to connect to GPS all day.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/201910711/06/2017Kume Island, JapanMarineUser: At 13:35:07, the GPS time output jumped to 13:37:16. It remained constant with this time offset for 10.5 hours. At 00:03:37, it jumped backwards from the offset time to the correct time. It maintained this time afterwards. This is a mature installation. Clear sky view. Other GPS receivers in operation did not experience problems. Were there any constellation issues at that time? If not, can you postulate a fault mechanism that could cause a constant time offset like this? Note: Question 6 did not allow "2017" as the year the disruption stopped.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. No correlating reports from other users or interagency partners.

User Equipment04/15/20198111/04/2017Anchorage, AKOtherUser: Regularly use GPS on mobile devices to set and monitor trails in the area. No app could find a signal so used GPSDiagnostic to determine what satellites were accessible. The app indicated that it could identify NO satellites.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

Unknown Interference05/20/20198010/28/2017Jordan Lake, NCUser: First indication of disruption were intermittent wrong time of day displays (roughly 3 hour advanced). GPS location tracking was also interrupted intermittently while sailing within 2 miles of specified location.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20197910/26/2017Alexandria, VATransportationUser: Mobile device GPS applications could not load the GPS, error stated GPS unavailable.

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20197810/24/2017Sea of JapanMarineUser: Both GPS systems onboard have been inoperable. GMDSS system is working correctly. App on phone using wifi is also working correctly.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

Unknown Interference05/20/20197710/18/2017Addison, TXAviationUser: Several pilots have reported a problem with a GPS outage in the vicinity of the airport. The problem is happening while landing and departing both runways, and all pilots have stated that their RNAV instruments malfunction when close to the airport.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

Authorized GPS testing was scheduled near the reported location and may have impacted GPS performance.

GPS Testing05/20/20197610/12/2017Scranton, PAAutomobileUser: I was traveling from Vermont to Winchester Virginia when, at some point, the gps advised to turn west on an interstate to Scranton PA. I got completely lost. All I would like to know is if there were any ongoing issues in that area yesterday.

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20197510/10/2017Macon, GAOtherUser: GPS unit could not fix any satellites until around 1300 on 10/10/2017. To be able to receive notifications of GPS constellation problems, where do I and or others sign up.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

Provided information on how to subscribe to GPS information products through NAVCEN website. Directed user to the approved GPS testing page on NAVCEN website.

User Equipment05/20/20197410/01/2017Ringwood, NJTransportationUser: The GPS was anchored at the last site that was used as a detour for traffic Road work. I attempted to restart the unit at different locations with no success.

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20197009/25/2017Hsinchu, ChinaUser: Dear Sir, Recently the 2 MSBs of IODC has been set to non-zero value, which is different from the zero value that has been in use for more than 10 years before. Although our engineers tried to be very careful in preparation of ROM code release for GPS chipset implementation, checking various test scenarios using GPS simulator, we still missed an issue in applying the 2 MSBs of IODC. This and recent change of those 2 MSBs becoming non-zero value caused about 2 million units of GPS receivers worldwide that worked perfectly for many years now suddenly have potential problem of unable to get position fix, we are beginning to get many customer problem reports coming in this week. May I ask if this IODC parameter will be set to a number < 256 again? And could the two MSBs of IODC be set to zero again as soon as possible please? Thank you very much.

NAVCEN: We have contacted the GPS Operations Center and they have informed us that: “After a recent ground system software update, we received reports of some users experiencing negative issues. As a result, we re-verified that our software update was indeed in complete compliance with IS-GPS-200 standards. Nonetheless, in order to continue to support all of our users to the maximum extent possible, we rolled back the software update to a previous version so that we can take the time to consult with the affected receiver manufacturer and proceed forward in a way to ensure dependable access to GPS for all users. In this case, as always, Air Force officials continue to work with their counterparts in the U.S. Coast Guard to analyze and respond to all user concerns.”

Encouraged user to supply additional information on impacts to user equipment and mitigations employed to deal with this change. Input shared with the U.S. Air Force.

User equipment does not meet IS-GPS-200 requirements. You can find the Interface Specification (IS-GPS-200) in the technical documentation section of GPS.gov under Interface Specifications (GPS.gov).

User Equipment05/20/20197209/25/2017Perugia, ItalyTimingUser: Civil Defense and Environemental Monitor application We have about 300 units which will stop to work if a cold start will happen. The unit cannot get basic information for first fix. They are installed worldwide in remote stations. Manufacturer of [manufacturer] reported the signal from GPS is no longer compatibile with these units, the units cannot be updated because the firmware is not accessible. We do not know the exact date of signal change, approximately the problem started in a time window between Mid August 2016 and 25 September 2016. Although this problem is generating costs to our company in terms or workaround and replacement of parts, there are many instrument that cannot be accessed easily and this will cause a interruption of services for the public interest. Thank you for your attention and cooperation.

NAVCEN Response: We have contacted the GPS Operations Center and they have informed us that: “After a recent ground system software update, we received reports of some users experiencing negative issues. As a result, we re-verified that our software update was indeed in complete compliance with IS-GPS-200 standards. Nonetheless, in order to continue to support all of our users to the maximum extent possible, we rolled back the software update to a previous version so that we can take the time to consult with the affected receiver manufacturer and proceed forward in a way to ensure dependable access to GPS for all users. In this case, as always, Air Force officials continue to work with their counterparts in the U.S. Coast Guard to analyze and respond to all user concerns.”

User equipment does not meet IS-GPS-200 requirements. You can find the Interface Specification (IS-GPS-200), dated July 2017, in the technical documentation section of GPS.gov under Interface Specifications (http://www.gps.gov/technical/).

User Equipment05/20/20197309/23/2017Djelfa Province, AlgeriaTransportationUser: Hello, On 23.09 we detected a problem with the GPS signal in North Africa and Eastern Europe creating GPS initialization problems and time fix for our GPS tracking devices. Practically they have stopped working on large areas that was covered by over 5000 GPS tracking units. Today the situation in Eastern Europe is going back to normal but persist in North Africa. Please let us know the cause of the signal problems and how long will take for the signal to return to normal. Thank you

NAVCEN response: We have contacted the GPS Operations Center and they have informed us that: “After a recent ground system software update, we received reports of some users experiencing negative issues. As a result, we re-verified that our software update was indeed in complete compliance with IS-GPS-200 standards. Nonetheless, in order to continue to support all of our users to the maximum extent possible, we rolled back the software update to a previous version so that we can take the time to consult with the affected receiver manufacturer and proceed forward in a way to ensure dependable access to GPS for all users. In this case, as always, Air Force officials continue to work with their counterparts in the U.S. Coast Guard to analyze and respond to all user concerns.”

User equipment does not meet IS-GPS-200 requirements. You can find the Interface Specification (IS-GPS-200), dated July 2017, in the technical documentation section of GPS.gov under Interface Specifications (http://www.gps.gov/technical/).

User Equipment05/20/20197109/22/2017Dallas, TXResearchUser: Starting last Friday, 22nd we noticed that the two high bits of the 10 bit IODC became non-zero. With all space vehicles as far as we can tell being non-zero by this Sunday. This is causing an ephemerides decding issue in our firmware preventing correct download of this data. Is this new behavior going to persist? If not when will it end? Is it possible to ask that the high bits cycle through 0 at least once per 6 hours for each space vehicle? Best Regards

NAVCEN: We have contacted the GPS Operations Center and they have informed us that: After a recent ground system software update, we received reports of some users experiencing negative issues. As a result, we re-verified that our software update was indeed in complete compliance with IS-GPS-200 standards. Nonetheless, in order to continue to support all of our users to the maximum extent possible, we rolled back the software update to a previous version so that we can take the time to consult with the affected receiver manufacturer and proceed forward in a way to ensure dependable access to GPS for all users. In this case, as always, Air Force officials continue to work with their counterparts in the U.S. Coast Guard to analyze and respond to all user concerns.

User equipment does not meet IS-GPS-200 requirements. You can find the Interface Specification (IS-GPS-200) in the technical documentation section of GPS.gov under Interface Specifications (GPS.gov).

User Equipment05/20/20196909/20/2017WorldwideAutomobileUser: It appears that the Subframe-2 IODC message two MSBs have changed from 0 to a non-zero value for the first time in the last 10 years in some or many GPS Sats. This is causing potentially 100s of thousands of [manufacturer] receivers to stop generating GPS fixes for some reason. When will the two MSBs of the IODC parameter be set back to zero again? Can this please be done as soon as possible so as to make these large numbers of fielded [manufacturer] receivers work again? Thanks much!

NAVCEN: We have contacted the GPS Operations Center and they have informed us that: After a recent ground system software update, we received reports of some users experiencing negative issues. As a result, we re-verified that our software update was indeed in complete compliance with IS-GPS-200 standards. Nonetheless, in order to continue to support all of our users to the maximum extent possible, we rolled back the software update to a previous version so that we can take the time to consult with the affected receiver manufacturer and proceed forward in a way to ensure dependable access to GPS for all users. In this case, as always, Air Force officials continue to work with their counterparts in the U.S. Coast Guard to analyze and respond to all user concerns.

User equipment does not meet IS-GPS-200 requirements. You can find the Interface Specification (IS-GPS-200) in the technical documentation section of GPS.gov under Interface Specifications (GPS.gov).

User Equipment05/20/20196809/19/2017Tacoma, WAMarineUser: GPS related equipment was interfered with when a bus was near the Ferry Terminal serviced. [Ferry operator] investigated and trouble shot the incident and found that Bus was indeed the cause of the disturbance and [bus operator] agreed to take the bus out of service until the problem could be identified.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User determined the cause of the interference was a transit bus operating near the location. Coordination between the ferry operator and the bus operator determined the cause was unintentional interference caused by improper equipment installation onboard the transit bus. The installation was corrected and the issue resolved.

Unintentional Interference05/20/20196609/03/2017Rotterdam, Netherlands, to Antwerp, BelguimAutomobileUser: While dringin, and despite several restarts of the system my build in vehicle GPS was systematically for about 30 min showing wrong location about half a mile to the east from correct position. At the same time a separate mobile phone navigation was showing correct position. This has not hapened previously.

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20196509/02/2017Concord, MAUser: I am near a highway; perhaps someone is using a GPS disruption box to avoid tolls. It happened again last night at around 10:27 EDT.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer, map provider or mapping application developer.

User Equipment05/20/20196408/30/2017Indiana to IllinoisTransportationUser: [equipment] as well as [equipment] GPS have not worked for more than 24 hrs. [equipment] GPS is displaying a red circle with line through it indicating no GPS service. [equipment] is continually down and states "all entries must be manual". Please help!

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20196208/22/2017Myrtle Beach, SCAutomobileUser: Mobile phone GPS application was not loading.

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20196008/11/2017South KoreaTimingUser: one of our customers claim that their GPS swap time at UTC 2200 to UTC 2400 and have done so multiple of times. This unit is placed close to the north boarder. Technical engineers are now traveling to the unit so that we can get more details on what is wrong with the installation. The second case is about the Olympic games which will be in Soul next year, summer. I have been asked if I can keep the sync for the broadcast system even if GPS is gone. The new IP based Digital TV system need GPS or IEEE 1588 to work well so we need a stable sync to get the digital information forward. So my question to you is: Do you know if the US has an alarm system in this area for GPS disturbance? Who can we contact and ask for alarms? Please support us! [Submitted by NAVCEN personnel from e-mail correspondence from reporting source.]

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact the Korea Communications Commission to assist with identifying radio frequency interference.

Unknown Interference05/20/20195708/08/2017San Clemente Island, CAMarineUser: For the last two weeks in our area of operations, we have been experiencing loss of signal on all 3 of GPS units. Our typical routes seem to be losing our position constantly. The last two days have been worse than usual. At times, we go from 3D to 2D and then to no fix at all. Please let me know if there is anything we can do to, or when we can expect to no longer receive these alarms.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

Authorized GPS testing was scheduled near the reported location and may have impacted GPS performance.

GPS Testing05/20/20195908/01/2017Helsinki, FinlandOtherUser: GPS lack about every 10-20 sec and not give any information after 3 sec, it cycle that. I think that USA do that on purpose beacose Russian and China warships are Baltic sea near the Finland to practiced together! Not nice at all!

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

Unknown Interference05/20/20194907/29/2017York, PA, and Washington County, MDOtherUser: Call centers in York, PA and Washington County, MD experiencing GPS timing issues on their [equipment]. This report was taken over the phone by the USCG Navigation Center.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

Equipment is known to have a GPS Week Number Rollover issue that occurred in 2017. A firmware update was issued in 2017. It appears the user did not apply the firmware update. User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20195007/29/2017Charleston, SCTimingUser provided no description beyond equipment type.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20194807/23/2017Port Hedland, AustraliaTransportationUser: Each Locomotive has two GPS rims fitted, on odd and one even and the odd GPS stopped working today here in Australia and also we have reports that the units in China also stopped working. These units provide location services for a Railway control system called ITCS and this has caused a total site outage and rendered the system inoperable due to the Kalman filter causing error and the safety system failing.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User reported a firmware update corrected the issue.

User Equipment05/20/20194707/22/2017Walnut, IATransportationUser: Map screen just says no GPS signal from western Iowa all the way across Nebraska.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20194607/12/2017Elizabeth, NJAutomobileUser: OUR PROBLEM IS MOSTLY ALL OUR CLIENTS, COMPLAINT ABOUT HAVING THE WRONG ADDRESS IN GPS. GPS GIVE THEM [address] ELIZABETH NJ 07208 INSTEAD OF [address] ELIZABETH NJ 07208

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20194507/10/2017Tulsa, OKTimingUser: Our receivers indicated a spike in phase error shortly after PRN 2 became visible. The phase error seemed to resolve itself when full signal strength was reached.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20194406/24/2017Charlotte, NC AviationUser: GPS reception was intermittent all day, when receiving a signal location was off by over 1000 feet, this was experienced while driving and while stationary flying multiple drones and lasted most of the day and was very unusual.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20194306/23/2017Ashtabula, OHCommunicationsUser: All 3 of my devices have put me about 250 miles south west of where i acually am. I live in Ashtabula Ohio and they all but me at an apartment in Galloway Ohio.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance. It is possible the user was experiencing a network error, or a problem with wireless services.

None05/20/20193906/22/2017Black Sea, Novorossiysk, RussiaMarineUser: GPS equipment unable to obtain GPS signal intermittently since nearing coast of Novorossiysk, Russian. Now displays HDOP 0.8 accuracy within 100m, but given location is actually 25 nautical miles off actual location.

NAVCEN: See U.S. Maritime Alerts 2017-005A-GPS Interference-Black Sea for further information on this interference. MSCI Portal

Unknown Interference05/20/20193806/19/2017Austin, Houston and Dallas, TXAutomobileUser: [Mobile] map application - the arrow icon begins to move off the road, spin or otherwise not move at all. Eventually, a "GPS Signal was lost" message appears, second mobile map application - error message "No GPS Signal".

NAVCEN: User encouraged to contact their map provider or mapping application developer.

Mapping Issue05/20/20193706/10/2017Stephens City, VAOtherUser: Mobile phone and GPS fitness tracker both received intermittent reception while traveling through the park.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20193606/02/2017Wenatchee, WAAutomobileUser: Navigation signal strength is low or non existent.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20193205/31/2017Estero, FLSurveyingUser: We are seeing GPS drop from 5/26,5/30,5/31 at around the 10:40 eastern time for a 15 minute period, for the location. Antenna is roughly 15 feet above the ground with little multi-path.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found to be unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20193105/28/2017New Orleans, LATransportationUser: No GPS signal being displayed.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20193305/24/2017Toulouse, France, and Athens, GreeceOtherUser: On the 24th of May 2017, some IODE/IODC of the ephemeris/clock information transmitted by PRN#10 from 18:23:30 to 23:59:59 were the same (40, 41, 42) than the ones used on the same day for that PRN from 14:00 to 18:23:59 while the navigation data were different in violation of the GPS ICD 200 IODE repetition rule (unicity over 6 hours) and of the GPS ICD 200 IODC repetition rule (unicity over 7 days).

NAVCEN: Forwarded report to the U.S. Air Force which manages the GPS constellation. They report the cause of the IODC repetition error was the result of an issue experienced with the ground control system. The problem has been corrected.

ICD_Violation05/20/20193005/22/2017Knoxville, TNAutomobileNAVCEN: No information provided by user. No response to requests for additional information. None05/20/20192905/19/2017Turin, ItalyResearchUser: Since 17/05/2017 GNSS signal at frequency L1=1575.42 MHz have been affected during the local afternoon hours, by spurious continuos wave signals. The main components of the spurious signal are at an offset of 0.5 MHz on both sides of L1. Further harmonics with lower power are also present. The investigation excluded that such interfering signal could be generated by local terrestrial sources, since it has been measured at several Km from the antenna with the same power level. Having observed a 24h repetition of the phenomena, the interference might be a case of intrasystem interference generated by GPS satellite with PRN 26 which was in view at the monitoring location for the 3 days during which the interference has been observed. The signal has been observed through our software receivers and by means of spectrum analyzers.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

The report was forwarded to the European GNSS Service Center. User encouraged to report the incident to the Italian communications regulatory authority for assistance.

Unknown Interference05/20/20192705/10/2017Porter, TXTransportationUser: My wife is a [rideshare] driver and the [navigation] applications would not establish our current position as of 11 pm on the 10 th . As far as I can tell other drivers are having the same issue . My wife and I are computer literate and gone over phone and tablet settings multiple times to ensure it is not our devices. each time we found that the GPS cant locate our position or track our position while moving.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found to be unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20192805/06/2017Wenatchee, WAAutomobileUser: For the last few weeks or so my newley installed [equipment] navigation system has shown only 0-1 bars of GPS signal. The week prior it seemed fine, but cant say exactly when it started only when I noticed. Sat 5/6/17 Went to a local town and GPS showed me over 60miles off of my current location this lasted for about an hour when all of a sudden the signal jumped to 3 bars and everything worked fine. Today 5/18 my signal strnegth again is 0-1 bars, but navigation seems to be farely accurate but jittery.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found to be unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20192604/11/2017Gutersloh, GermanyAgricultureUser: Farmers in Gugersahol, Germany are reporting that there GPS units stop functioning.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found to be unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance. User acknowledged equipment issue.

User Equipment05/20/20192404/02/2017Channel Islands, CAMarineUser: Several systems, across all of our assets at sea, all affected

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

Authorized GPS testing was scheduled within 200 miles of the reported location and may have impacted GPS performance.

GPS Testing05/20/20192303/29/2017Denver, COAutomobileUser did not provide details of mobile device mapping software application error.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact equipment manufacturer or application developer for further assistance. Most likely caused by incorrect equipment or application settings.

User Equipment05/20/20191803/19/2017El Monte, CAUser: I have lived her for over 1 year and no one has been able to use GPS.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/20/20191603/10/2017Condon, ORAutomobileUser: Travelled to Condon, Oregon on remote, unpaved roads. When I left Condon the unit directed me first south and then west.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20191503/04/2017Lyons, GATransportationUser: Our home is located on the west side of the highway. GPS directs drivers to turn onto the east side of [the highway] rather than to the west.

NAVCEN: User provided information on how to contact mapping software providers to update their location details.

Mapping Issue05/20/20191403/01/2017Clarion, PAUser: Unit has 1-2 bars of signal in an area clear of trees buildings or high tension power supply. Unable to aquire location while driving through Pennsylvania.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20191302/26/2017Williamstown, NYAutomobileUser: My GPS has been down and I would like to know when it will be up again.

NAVCEN: Contacted user and determined GPS unit was providing incorrect location. Another device was operating properly at the same location. User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20193402/14/2017Barcelona, SpainAutomobileUser: [No description provided about a mobile phone problem.]

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found to be unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

The report was forwarded to the European GNSS Service Center. User encouraged to report the incident to the Spanish communications regulatory authority.

Unknown Interference05/20/20191202/08/2017Chandler, AZAviationUser: There is a small corridor at the Chandler airport in Arizona that has a loss of GPS signal.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance.

Report referred to the FAA for aviation support and response.

Unknown Interference05/20/20196102/06/2017Oberpfaffenhofen, GermanyUser: The reason I am contacting you relates to the test of power increase on part of the GPS constellations as announced by the USAF in January. I am wondering whether you can shed any light on the root cause of these DCB sub-daily switches and provide some recommendations how to best deal with them in code-based single point positioning and phase-based precise point positioning?

NAVCEN: The GPS Operation Center (GPSOC) stated these configuration changes were published in NANU 2017005.

GPS Testing05/20/2019901/26/2017United KingdomTimingUser: This has been happening over the last 4 days we have seen a quantum leep in indications, our recivers are not the best and we are looking at replacing them but something has changed and we would like to know how we can compensate for the change as it is effecting service as we are getting time jumps

NAVCEN: 5 January 2017 the Civil GPS Service Interface Committee Executive Secretariat release the following message: Beginning 25 January 2017, Air Force Space Command (AFSPC) will conduct a limited duration test implementing an increase of the L1 C/A power level on the GPS Block IIR-M and IIF satellites (19 vehicles). The C/A power will remain within IS-GPS-200-H specifications and the power increase is not expected to increase the noise floor by more than 0.3 signal-to-noise ratio in the worst case. AFSPC reports, "We assess that there will be no adverse impacts to civil, commercial or military GPS users, but anyone who experiences issues during this test should address them through established reporting channels." Civil, non-aviation, GPS users should contact the U.S. Coast Guard Navigation Center at 703-313-5900 or online at http://www.navcen.uscg.gov/?pageName=gpsUserInput. Civil aviation GPS users should contact the FAA and file a report at https://www.faa.gov/air_traffic/nas/gps_reports/. All other nonoperational concerns or inquiries regarding this test should be directed to Air Force Space Command at a3sm.wf@us.af.mil.

GPS Testing05/20/2019701/18/2017Binghamton, NYAutomobileUser: It was reporting incorrect speed. I was going 55MPH and it was reporting 58-63 MPH. It was reporting my position off to the east by about 200-500 feet.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/2019601/14/2017Slidell, LAUser: While driving Interstate I noticed phone was reporting "seeking GPS" several times.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer or mapping application developer for further assistance.

User Equipment05/20/2019801/05/2017ChileLaw EnforcementUser: There were large spikes in geozone alarms on 3 consecutive days caused by a country-wide GPS position shift >125 feet, generally to the SouthEast. This affected 5% of the 4000+ units deployed. The times of increases in Inclusion Zone alarms are: Jan 06-2017, between 04:35:00 and 04:40:00 UTC (5 minutes, 404 alarms) Jan 07-2017, between 04:37:00 and 04:45:00 UTC (8 minutes, 337 alarms) Jan 08-2017, between 04:06:00 and 04:09:00 UTC (3 minutes, 165 alarms) All units had >4 satellites in use (actual number unknown). Maps and other data are available for the 3 GPS shift incidents.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported outage. Space Weather was reviewed and found unlikely to have impacted GPS performance. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for further assistance.

User Equipment05/20/20192001/03/2017San Angelo AirportAviationUser: The GPS systems in normal mode not military have been interrupted since the installation of the command and control system at the North End of our airport. During testing of the system the problem has been confirmed to affect both ground and air operations at and within 15 miles South of the airport.

NAVCEN: Report referred to FCC. FCC conducted an investigation and found no further interference events.

Unintentional Interference05/20/2019101/02/2017North Carolina - South Carolina borderTransportationUser: GPS would say when you plug in that there isnt any satellites to connect to but when you drive for about 5 miles it would pick up connection. Today when being turned on, says no satellite connection and has yet to come on. Been on for approximately 4-5 hours driven about 100 miles, still no connection.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance.

User Equipment05/20/2019201/01/2017Elizabeth, NJTransportationUser: My business is located in Elizabeth, NJ. At the end of the block there is a bridge that has been closed for several years, however it is not updated on any GPS. So we have a lot of 18 wheelers that come down and have to make a u-turn in front of my business. I need to know how I can update this so it will stop happening.

NAVCEN: User provided information on how to contact mapping software providers to update location details.

Mapping Issue05/20/2019411/16/2016Rennes, FranceResearchUser:I experimented high range error on PRN 32 (7h54 to 11h45) and on PRN 17 (20h00 12 to 23h48) the sixth of november 2016. Coul you confirm the issu please.

NAVCEN: The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect GPS signal integrity at the time and vicinity of the reported problem. Space weather was reviewed and found unlikely to have impacted GPS performance. There were no authorized GPS tests in the area. No correlating reports from other users or interagency partners.

User encouraged to contact their equipment manufacturer for assistance.

User Equipment05/20/2019
GPS User Issue Detection & Evaluation (GUIDE) Tool (2024)

FAQs

How to do GPS testing? ›

Testing scheme: two cover gps systems are installed on vehicle simultaneously, the receiving antenna of its two GPS is placed side by side with roof (identical with static test hardware laying method), test site is a horizontal section of hollow in certain university, experimental program for from initial point vehicle ...

What is the global psychotrauma screen? ›

Global Psychotrauma Screen (GPS)

The GPS is a brief instrument meant to screen for a range of trauma-related psychological problems, as well as for risk and protective factors.

How do I check my GPS accuracy? ›

On an Android phone or tablet, you can check if your geolocation is accurate by opening the Maps app. See if the blue dot is at the right spot. If you don't see a blue dot, tap “Your location” in the bottom right.

What is GPS assessment? ›

This Year 5 End of Year GPS Assessment helps identify progress by assessing against each of the Year 5 National Curriculum Grammar, Punctuation and Spelling objectives. The Teacher Objectives Sheet allows you to identify progress as well as gaps in pupils' knowledge.

What are the symptoms of psychotrauma? ›

Symptoms tend to vary by age. Avoidant symptoms may be absent or children may not report them. Physiologic symptoms may be headaches or stomachaches and not the classic symptoms of autonomic arousal. Fears and anxieties unrelated to the trauma may occur in younger children.

What is the trauma symptom screening tool? ›

The PTSD Checklist for DSM-5 (PCL-5) is a 20-item self-report measure that assesses the 20 DSM-5 symptoms of PTSD. It has a variety of purposes such as monitoring symptom change during and after treatment, screening individuals for PTSD, and making a provisional PTSD diagnosis.

What is the screening tool for complex trauma? ›

The International Trauma Questionnaire (ITQ) is an 18 question self-report measure focusing on the core features of Post Traumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD).

How do I check if my GPS is working? ›

Android devices

Go to "Settings" > "Location Data". Check that "Location information access" is on — the button must be blue. Go to "Settings" > "Location Data" > "App permission" — it may also be called “Location” depending on your device.

How to do navigation testing? ›

There are different types of navigation testing methods, such as tree testing, prototype testing, usability testing, and A/B testing. Each method has its advantages and disadvantages. Choose the method that is most appropriate for your goals and budget. Your testers should represent your target users.

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