Israeli pilots have reported the loss of a GPS signal near Tel Aviv for nearly three weeks and officials believe Russia could be to blame.

The International Federation of Air Line Pilots’ Associations (IFALPA) reported the disruptions in a June 25 press release. The Israel Airports Authority (IAA) confirmed the reports June 26.

The Israeli Defense Forces radio station, Galei Tzahal, then reported that previously unknown interruptions in the GPS signal were coming from Russia, according to a June 27 BBC article. This sentiment was later confirmed to C4ISRNET by Todd Humphreys, a professor at the University of Texas studying satellite navigation, autonomous systems, and signal processing.

Humphreys said his research found that for the past year Russia has been broadcasting a unique combination of jamming and spoofing signals from Syria which he calls “smart jamming.”

“What’s going on in Israel is not that Israel is the target of Russian aggression, it’s that it is simply collateral damage,” Humphreys said.

This report comes as U.S. military leaders have become increasingly concerned about not having access to accurate position, navigation and timing capabilities.

The GPS interruption can deter rudimentary aircraft that rely on civilian GPS signals, said Humphreys. He suspects that the Russian military has made improvements to their transmitters and the change has led to the interruption.

“The intent not to fool the servers but to deny service,” Humphreys said. “My suspicion is that the broadcasts they have been making for the last year and a half out of Syria are primarily designed to deter drones and incursions into airspace they wish to control."

Humphreys said his guess is that the signals are coming out of Khmeimim Air Base in Syria. He said he knows signals are coming from this base because he can track the signal from space using a GRID receiver on the International Space Station owned by the Naval Research Lab, Cornell, University of Texas, and Aerospace Corp.

According to a BBC report, Russia has denied responsibility in the attacks and called them “fake news.”

At the same time, Dana A. Goward, the president of Resilient Navigation and Timing Foundation, said his group and 14 other maritime organizations sent a request to the U.S. Coast Guard June 25 requesting an international resolution against GPS jamming and spoofing.

“Jamming and spoofing of GPS is clearly a hazard. These signals are relied upon for navigation and when they are interfered with...then they can pose a real hazard to safety of life,” he said.

Howard said this resolution does not ask for nations to abstain from interfering with GPS signals, but for more transparency when they do. The resolution asks for notification if service was to be disrupted.

While the resolution applied only to maritime purposes, Howard said he believes it should apply elsewhere as well.

While the interruptions from Syria have been taking place for more than three weeks, no immediate solution to stop these signals appears evident.

Yoab Zangvil, chief technology officer and co-founder of Regulus Cyber, a senor security company in Israel, said his firm is working to detect these attacks so it can notify the appropriate parties when they are being spoofed.

While the reports coming out of Israel are solely related to civilian technology, Humphreys said the Russians have shown the ability to block military grade equipment in the past. In 2018, NBC News reported the Russian military to be jamming signals to U.S. drones effecting military operations in Syria. In addition, Gen. Raymond Thomas, the former head of Special Operations Command, said in 2018 at the annual GEOINT symposium in Flordia “Right now in Syria we are operating in the most aggressive EW [electronic warfare] environment on the planet.”

Kelsey Reichmann is a general assignment editorial fellow supporting Defense News, Fifth Domain, C4ISRNET and Federal Times. She attended California State University.

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