ITHACA, N.Y. – From cars to commercial airplanes to military drones, global positioning system technology is everywhere, and researchers have known for years that it can be hacked or “spoofed.”
Now, the best defense, Cornell University researchers say, is a good offense — by detecting false signals and creating countermeasures that unscrupulous GPS spoofers can’t deceive.
Researchers led by Mark Psiaki, professor of mechanical and aerospace engineering, got to test their latest protections against GPS spoofing during a Department of Homeland Security-sponsored demonstration last month in the New Mexico desert at the White Sands Missile Range.
GPS is a navigation and timing system that uses satellites circling the Earth to transmit signals and provide precise information on a receiver’s location. Spoofing is the transmission of false GPS signals that receivers accept as authentic, allowing hackers to gain control over planes, vehicles or other devices that rely on GPS technology.
During a much-publicized June 19 demo of a mini helicopter’s GPS signal being spoofed by using live “on-air” transmissions to confuse real GPS signals, Cornell researchers Psiaki, senior engineer Steve Powell and graduate students Brady O’Hanlon and Ryan Mitch tested a receiver modification that can differentiate spoofed GPS signals from real ones. Psiaki said their latest countermeasure allowed the Cornell group to correctly detect spoofing in three cases during the demo.
“This is strong confirmation that our system can successfully detect spoofing in an autonomous mode using short segments of GPS receiver data. It is the first known detection of this type of attack from a live, on-air spoofer,” Psiaki said.
“The idea is not just for us to make spoofers so we can show bad things can happen, but also to gain insight into countermeasures in typical GPS receivers so they can be less vulnerable to attack,” Powell said.
In addition to its role in commercial and military aircraft navigation, GPS signals also help control the nation’s power grid, as well as cell phone towers and even automated stock trades.
Researchers also warn that GPS spoofing is a growing threat. Last year, Iran claimed to have spoofed – and downed – a GPS-guided American drone. Such an attack, Psiaki said, might have been carried out using techniques similar to those demonstrated at White Sands if the drone had been using civilian GPS signals.
