Space agency launches project targeting satellite navigation jamming

　　The U.S. government appears to be moving closer to deciding whether to bring back the enhanced eLoran system as a backup to the location, navigation and timing information provided by GPS signals.

　　Satellite navigation has become a global utility, but it is prone to interference. The European Space Agency's new NAVISP R&D program is prioritizing research into countering jamming and spoofing of satellite navigation signals, exploring various methods.

　　How can medium-sized Global Navigation Satellite System (GNSS) satellites spread over 22,000 kilometers away to provide global users with positioning, navigation and timing data anytime, anywhere?

　　According to an ESA press release, the answer is that the signal itself is very low-power, with an energy equivalent to shining the beam of a car's headlights from one side of Europe to the other. Satellite navigation receivers store complex codes embedded in the signal and use them to generate a full-power replica of the weak signal it receives.

　　This approach allows the use of tiny antennas, small enough to be embedded in smartphone chips, making satellite navigation widely available. But it also means that satellite navigation signals can easily be overlaid or jammed, either accidentally or deliberately.

　　"Jamming" refers to denying sat-nav service by blocking the signal with noise, like the famous American truck driver shutting down the entire airport system while passing Newark Airport with a GPS jammers in his gear. Or the experience of conducting military exercises in various countries where satellite-navigation jamming extends to civilian infrastructure—in one case, shutting down emergency pagers and ATMs, as well as air and ship traffic control.

　　"Spoofing" involves sending users false, deliberately misleading sat-nav messages and has been shown to shoot down drones and divert ships

　　The ESA's Navigation Innovation and Support Program works with European industry to develop innovative navigation technologies, with the fight against jamming and spoofing as a top priority, especially as satellite navigation will form the basis for new safety-critical systems such as driverless cars.