Tampering with GPS signals can cause big problems in both shipping routes and financial markets, warned experts at a conference on GPS security. The technology is routinely used in navigation and time synchronization nowadays, but signals are left vulnerable to jamming and spoofing.
This is partly because GPS signals are relatively weak: “A GPS satellite emits no more power than a car headlight, and with that it has to illuminate half the Earth’s surface,” said David Last, former president of the Royal Institute of Navigation, to the BBC.
Jamming devices work by broadcasting a signal at the same frequency as GPS, and can be bought for less than $100 online. When researchers set up 20 jamming monitors in locations around the UK, they caught 60 incidents in 6 months. They think most of these are from stolen trucks, where thieves jam the truck’s GPS to keep from broadcasting its location. According to Last, jamming GPS ships on ships isn’t much harder: Tests found that every major system was affected by a device with less than 1/1000 the power of a cell phone. The Financial Times reports: