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GPS Problem Reports Status
GPS Problem Reports Status

Civil GPS Users are encouraged to submit reports of GPS problems to NAVCEN. A form to submit reports can be found on our GPS Problem Reporting webpage. Some information from those reports is shared here along with input from interagency partners and the most likely cause of the report.

Descriptions for each of the fields is at the bottom of the page.

* Fields are as provided by the reporting source and are unedited.
*Date/Time of
Disruption
Date
Submitted
Location *Type Description Cause NAVCEN
Date Closed
04/15/2019    9.00 UTC 04/17/2019 Abeokuta, Nigeria Surveying User: 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.
Other 04/24/2019
04/15/2019    13:30 CST 04/16/2019 Abilene, TX Surveying User: 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.

NAVCEN requested additional information but the reporting source has not responded.
Unknown Interference  
04/14/2019    16 CET 04/15/2019 Warsaw, Poland Transportation User: 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 Equipment 04/24/2019
04/07/2019    00-00 Middle East Time (+3:30) 04/14/2019 Tehran, Iran Transportation User: 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.
Other 04/24/2019
04/06/2019    11:00 Near East Time 04/08/2019 Fahud, Oman Surveying User: 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.
Other 04/24/2019
04/05/2019    03:00 CET 04/06/2019 Oulu, Finland Communications User: 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."

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

User has acknowledged the problem is related to the how their equipment is handling the GPS Week Number Rollover.
User Equipment  
04/04/2019    8:45 PM CST 04/05/2019 United States Communications At 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.
Other 04/24/2019
03/28/2019    3:00 EST 03/28/2019 None provided User: 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 Issue 04/24/2019
03/19/2019    1040 UTC 03/20/2019 Pireaus, Greece Other User: 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 Interference 04/16/2019
03/18/2019    22:29 CET 03/19/2019 Madrid, Spain Other User: 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 Interference 04/16/2019
03/14/2019    13:51 GMT 03/14/2019 Redmond, WA Other User: 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]."
Other 04/16/2019
03/07/2019    11:20 UTC 03/07/2019 Dongguan, China Marine User: 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 Interference 04/16/2019
01/11/2019    20:45 UTC 02/14/2019 United States Surveying 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.
Other 04/16/2019
02/13/2019    03:26 EEST 02/13/2019 Beirut, Lebanon Marine Reporting source: 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 Interference 02/21/2019
02/09/2019    0150 Eastern African Time 02/10/2019 Hodeidah, Yemen Marine Reporting source: 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 Interference 02/21/2019
11/15/2018    unknown PST 01/04/2019 Washington State Timing Reporting source: 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 Equipment 02/01/2019
01/15/2018    1900 UTC 12/13/2018 Austin, TX Automobile 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 reporting source: 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 Equipment 12/17/2018
12/04/2018    0930 Mountain Standard Time 12/04/2018 Denver, CO Research 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.

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 Equipment 12/07/2018
11/01/2018    08:00 EST 11/25/2018 Raleigh-Durham, NC Surveying GPS unit has ceased to display valid date and time information and reverted to the year 1999. 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). Date/time of problem onset is estimated.

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 Equipment 11/26/2018
11/18/2018    14:50 UTC 11/18/2018 Hadera, Israel Marine Intermittent loss of GPS near Hadera, Israel

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect 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 Interference 12/17/2018
11/17/2018    0245 UTC 11/17/2018 Straits of Tiran Marine 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.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect 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 Interference 11/20/2018
11/10/2018    23:59:43 CET 11/16/2018 North Sea Marine 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.

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 Equipment 11/27/2018
11/11/2018    11:33 UTC 11/13/2018 Usuda (Japan), Maui (Hawai - USA) ... Other 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).

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_Violation 11/15/2018
11/10/2018    09:00 CST 11/11/2018 Evansville, IN First Responder On 22 October the units began reporting a date of 11 March 1999. Time is correct, date is off.

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 Equipment 11/14/2018
03/29/2018    0900 EST 11/08/2018 York, PA Other 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.

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 Equipment 11/14/2018
11/04/2018    1800 (Arabic) Egypt Standard Time (+2:00) 11/04/2018 35 - 04.4N, 034 - 48.1E Marine 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.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect 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 Interference 11/14/2018
11/01/2018    1600 UTC 11/01/2018 Haifa Port, Israel Marine Erratic GPS signal reception.

The GPS Operations Center reviewed the GPS Constellation and Control Segment, there are no known anomalies that might affect 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 Israeli Ministry of Communications.
Unknown Interference 11/14/2018
10/29/2018    07:00 Near East Time 10/31/2018 Strait of Hormuz Marine GPS unit intermittently lost signal. 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 GPS Operations Center reviewed the 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 Interference 11/01/2018
10/21/2018    10:00 (Arabic) Egypt Standard Time (+2:00) 10/27/2018 Santorini, Greece Marine Fish-finder does not synchronize date and time.

The GPS Operations Center reviewed the 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 Equipment 10/29/2018
10/22/2018    8:00 Mountain Standard Time 10/24/2018 Fort Collins, CO Timing GPS 1PPS synchronization units of one make reporting incorrect time. On 22 October the units began reporting a date of 11 March 1999.

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 Equipment 10/29/2018
10/13/2018    10:00 UTC 10/17/2018 Jeddah Port, Saudi Arabia Marine 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.

The GPS Operations Center reviewed the 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 Interference 10/17/2018
10/16/2018    19:45 UTC 10/16/2018 Leesburg, VA Transportation Unit reported loss of GPS lock. It was actively searching for a lock. The problem resolved within about 5-10 minutes.

The GPS Operations Center reviewed the 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 Equipment 10/17/2018
10/15/2018    0846 Eastern African Time 10/15/2018 Jeddah Port, Saudi Arabia Marine Vessel lost GPS Signal while approaching the Jeddah Port on 15/10/2018. Out-bound vessels told us they did not have GPS Signals. But GPS Signals restored once they are about 8 miles from the Port. Conclude it is localised to this port area. When our Vessel is about 7 miles away, GPS signal returned on GPS receivers. Same as other ships had shared earlier.

The GPS Operations Center reviewed the 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 Interference 10/16/2018
10/08/2018    07:40 UTC 10/10/2018 Huddersfield, UK Communications 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.

The GPS Operations Center reviewed the 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 Equipment 10/11/2018
10/08/2018    0430 UTC 10/08/2018 Rochester, NY Timing Two large phase events were observed on October 8th.

The GPS Operations Center reviewed the 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 Equipment 10/11/2018
08/01/2018    0730 PST 10/02/2018 Lakewood, WA Transportation For many months now, GPS goes off track when directly north of McChord Field on I-5.

The GPS Operations Center reviewed the 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 Equipment 10/11/2018
10/01/2018    0030 EEST 10/01/2018 Port Said, Egypt Marine While making approach to Port Said on 30 October we lost GPS fix. While at Port Said anchorage we lost GPS due to interference 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.

The GPS Operations Center reviewed the 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 Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 11/14/2018
09/27/2018    1100 CET 09/28/2018 Plymouth, UK Marine Experienced an intermittent fault 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.

The GPS Operations Center reviewed the 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 Interference 10/11/2018
09/11/2018    0330 GMT 09/18/2018 Kabul Communications 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.

The GPS Operations Center reviewed the 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 Interference 10/11/2018
08/29/2018    18:00 Middle East Time (+3:30) 09/12/2018 Tehran, Iran Communications Mobile phone clock synchronization problem. Unable to access internet, Waze, or other GPS applications.

The GPS Operations Center reviewed the 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 Equipment 09/17/2018
09/07/2018    00:40 CET 09/06/2018 Bratislava, Slovakia Automobile Two different GPS tracking modules placed outside window cannot find GPS signal.

The GPS Operations Center reviewed the 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 Interference 09/10/2018
09/06/2018    1359 CST 09/06/2018 Gulf of Mexico Marine Multiple vessels in our area experienced degradation of GPS signal resulting in elevated PDOP. GLONASS systems were unaffected.

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 tests 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 Testing 09/10/2018
08/20/2018    1700 PST 08/21/2018 San Bernardino, CA Transportation GPS devices showing satellites with no lock.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
08/10/2018    00:40 Phoenix Standard Time 08/20/2018 Scottsdale, AZ Other Testing mixed mode tracking Y-code and M-code. Receiver lost lock on the L1 channel, L2 continued to track. Could track C/A, but not L1.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
08/11/2018    1605 China Taiwan Time 08/11/2018 50 miles from Qingdao, China Marine 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.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
08/03/2018    11:30 EST 08/03/2018 Avon, IN Other 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.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
07/23/2018    1428 EST 07/24/2018 Port Said, Egypt Marine Vessel moored in Port Said Egypt when they lost the primary and secondary GPS. Disruption was intermittent. GPS also showed the ships location west of Alexandria on at least one occasion.

See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 11/14/2018
07/04/2018    1500 EEST 07/04/2018 Port Said, Egypt Marine 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.

See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 11/14/2018
07/04/2018    1500 EEST 07/04/2018 Port Said, Egypt Marine Vessel 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. MSCI Portal
Unknown Interference 11/14/2018
06/28/2018    0600 CST 06/28/2018 Rockport, Texas 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. Mapping Issue 07/30/2018
06/28/2018    10:00 (Arabic) Egypt Standard Time (+2:00) 06/28/2018 Ankara, Turkey Other Product developer not getting valid fix. Tried to get a fix with cell and could not. The phone saw one satellite and it had a very weak SNR.

The GPS Operations Center reviewed the 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 partner.
User Equipment 08/30/2018
06/15/2018    10:00 EST 06/24/2018 Powell, Ohio Transportation Mapping application showed GPS unavailable. Requests if there was an outage in the area.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
06/16/2018    11 Brazil Eastern Time 06/22/2018 Vila do Conde, Brazil Marine Every day in the morning time up to lunch time the GPS gives warnings about unsafe position.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
06/15/2018    0730AM CST 06/15/2018 Nashville, Tennessee Other 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.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
05/26/2018    08:44 UTC 06/08/2018 Yellowknife, Canada  Other 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.
Report forwarded to GPSOC. Issue was covered by the release of NANU 2018028.
None 07/30/2018
05/01/2018    16:30 EST 06/04/2018 Doylestown, Pennsylvania  Communications 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. Mapping Issue 07/30/2018
05/10/2018    0008 GMT 05/31/2018 Fairbanks, Alaska Other 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.

The GPS Operations Center reviewed the 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.
Authorized GPS Testing is announced on NAVCENs website.
GPS Testing 08/30/2018
05/29/2018    14:00 Near East Time 05/30/2018 Le Port Reunion Island Surveying 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.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
05/27/2018    0600 PST 05/27/2018 Bend, Oregon Automobile Getting a NO GPS symbol on our unit, tried resetting and powering on and off, no swings have changed since last use.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
05/18/2018    1730 (Arabic) Egypt Standard Time (+2:00) 05/18/2018 100NM off Port Said Marine For the past hour GPS signal is either lost or incorrect in approximately 5 minute increments. Vessels in the area are reporting the same.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/18/2018    1430 (Arabic) Egypt Standard Time (+2:00) 05/18/2018 35 NM North of Egyptian coast Marine GPS total signal loss on 3 occasions. Last noted GPS interruption was on 30 APR 2018.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/10/2018    0954 UTC 05/10/2018 Port Said, Egypt Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/30/2018
05/09/2018    6:45 EST 05/09/2018 Armenia, Quindio, Columbia Other All my phones, my friends phones, and tablets are currently experiencing this outage in Armenis, Quindio, Colombia.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
04/30/2018    11:00 EST 05/01/2018 Orlando, Florida Aviation Producer of high accuracy, aviation time, space, and position information equipment; develop, produce, and maintain equipment. 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 ongoing interference is impacting our ability to conduct operations.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
04/23/2018    8:30am Mountain Standard Time 04/25/2018 Colorado Springs, Colorado 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. Mapping Issue 07/31/2018
04/17/2018    11:00 EEST 04/18/2018 Romania and Vietnam Marine 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.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
04/18/2018    08:00 GMT 04/18/2018 EASTERN MEDITERRANEAN SEA Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
04/16/2018    1700 (Arabic) Egypt Standard Time (+2:00) 04/18/2018 Port Said, Egypt, N entrance of Suez Canal Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
11/06/2017    13:35:07 GMT 04/10/2018 Kume Island, Japan Marine User: 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 Equipment 04/15/2019
03/22/2018    0200 (Arabic) Egypt Standard Time (+2:00) 03/26/2018 DAMIETTA PORT, Egypt GPS EXPERIENCES LOSS OF SIGNAL PROBLEM FROM LAST 5 DAYS. MOST OF THE TIME IT HAPPENS NEAR EGYPT, LEBANON AND IN EASTERN MEDITERRANEAN REGION.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/21/2018    20:00 (Arabic) Egypt Standard Time (+2:00) 03/22/2018 AT SEA, POST DEP PORT SAID, Egypt Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/21/2018    0400 EEST 03/22/2018 Suez Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/19/2018    1100 EEST 03/19/2018 Cyprus Marine 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 we can promulgate relative messages in case necessary?
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 08/01/2018
01/01/2018    1100 AEST 03/19/2018 Southern Tasmania Marine 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?

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
03/18/2018    0600 EEST 03/18/2018 Port Said, Egypt Marine 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.
See U.S. Maritime Alerts 2018-004A and 2018-004B for further information on this interference. MSCI Portal
Unknown Interference 07/31/2018
03/07/2018    500 PST 03/07/2018 San Francisco, California Automobile 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.
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 user's own risk. Refer to Notice Advisory to NAVSTAR Users (NANU) 2014038 and 2014039.
User Equipment 07/31/2018
02/19/2018    04:42 UTC 02/27/2018 Washington (USA), Yellowknife (Canada), Brest (France) Other 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).
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_Violation 07/31/2018
02/16/2018    1400 EST 02/16/2018 West Palm, Florida Marine No description provided.

The GPS Operations Center reviewed the 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 Equipment 08/30/2018
01/31/2018    0700 UTC EEST 02/01/2018 Bad Pyrmont, Germany Timing This morning I was contacted by my colleagues who both have observed an anomaly in the timing characteristics of the GPS signal. One 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 the other receiver is measuring the GPS offsets against its internal HQ OCXO showed a time drift of +150ns and then back to zero. Both have used different types of receivers. 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.

The GPS Operations Center reviewed the 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 Interference 08/30/2018
01/08/2018    7:30 pm PST 01/25/2018 Hinkley,California Automobile 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.
No correlating reports from other users or interagency partner.
Mapping Issue 08/02/2018

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Date / Time of Disruption: Date and time of the report as provided by the reporting source.

Date Submitted: Date the report was submitted to NAVCEN.

Location: The City and State location of the reported problem based on input from the reporting source. Latitude and longitude may be used for maritime reports.

Type: Installation type as provided by the reporting source. Choices include: Agriculture, automobile, aviation, communications, first responder, marine, law enforcement, research, surveying, timing, transportation, and other (with a fillable field).

Description: Description of the problem. This information from the reporting source is edited for clarity and to remove personal and equipment manufacturer identifying details. The description also provides constellation analysis information as provided by the GPS Operations Center, a determination if authorized GPS testing might have been a factor, and information on correlating reports from other users and interagency partners.

Cause: The most likely cause of the report based on interagency input.

NAVCEN Closed Date: NAVCEN collects interagency input and provides a detailed response to the reporting source for each report submitted. If there are no further questions from the reporting source, and NAVCEN has no other correlating information, NAVCEN will close the case. The results of interagency input will be included in the description field when the case is closed. This date may not correspond to the event end date.