While examining data collected by GPS tracking stations, a team of researchers noticed a mysterious pattern. Over the past seven years, the team documented 75 days in which there was a sudden drop in signal strength that occurred simultaneously across Europe. An extensive investigation traced the disturbances to a small constellation of Russian satellites, which may be jamming GPS signals on purpose.
A recent investigation Led by Todd Humphreys of the University of Texas at Austin, they discovered that the Russian satellite Kosmos 2546 may have been used to jam GPS signals on a continental scale as part of scheduled operations. While the purpose of the signal jamming is still unclear, the findings could have broader implications for electronic warfare in global conflicts. The findings have not yet undergone peer review, but the researchers submitted the paper for review to NAVIGATION, the journal of the Institute of Navigation.
Only during business hours
The team behind the paper examined publicly available data collected by global navigation satellite systems (GNSS) ground-based tracking stations. From January 2019 to April 2026, researchers found 75 cases of similar wide-area interference.
All receivers noticed a sudden drop in signal at the same time. The jamming events lasted less than 10 seconds each and covered areas from Spain and Poland to Canada. This indicated that the signal interference could not have been caused by a terrestrial system but must have come from space.
The brief bursts also occurred within a narrow band of frequencies centered at 1,577.5 megahertz, which coincides with the part of the spectrum used by the GPS satellite constellation and its European counterpart, GNSS.
The sudden signal drop also occurred on Tuesdays, Wednesdays and Thursdays during business hours, suggesting this was part of a scheduled operation and not inadvertent interference.
Find the culprit
Using the data they had collected, the researchers calculated that the source must be located at least 1,200 kilometers (745 miles) above the Earth’s surface. They then began investigating which satellites at that altitude were over the affected areas during the interference periods.
The team narrowed it down to a handful of suspicious satellites. After refining their search, the orbit of a single satellite aligned perfectly with the continental-level interference events. Kosmos 2546 is part of a constellation of Russian military early warning satellites used to detect ballistic missile launches. According to the article, at least one of the satellites in the constellation was above the horizon during each recorded signal interference.
The article suggests that the signal jamming events were tests that prevented the system from being detected. One clue is that the signal was slightly off the GPS frequency. “If you’re going to test this capability, then you should test it in the vicinity of the signal you want to jam, but not right on that signal,” Humphreys said Veritasium during an interview. “And you test it only briefly to make sure everything still works.”
These tests, while mostly harmless for now, could have much more damaging implications. “In the future, when there’s a hot conflict, they’ll go ahead and tune their transmitter to the GPS band, but it’s much more damaging now that it’s right in that band,” Humphreys added.
Another indication that GPS jamming is part of targeted testing is that researchers detected a second burst of jamming aimed at a lower frequency, overlapping with signals from China’s BeiDou navigation system.
“I can no longer say with confidence that this is accidental,” Humphreys said during the interview. “I’m leaning toward this being a periodic test of a capability that would be very damaging if deployed in anger.”
