Practical Software Defense for GPS Spoofing on a Hobby UAV

Autonomous systems, such as unmanned aerial vehicles (UAVs) and self driving cars, operate by reacting to physical phenomena captured by onboard sensors. Current UAVs rely on the Global Positioning System (GPS), or other global navigation satellite system, to determine their location on Earth. Consequently, the GPS receiver can be used as an implicit control channel for autonomous systems. We propose a software defense that uses observations from independent sensor systems to detect GPS spoofing. We modify an open source UAV control program to incorporate our defense and evaluate our defense on hobby-grade drone hardware using simulated GPS spoofing. In our field tests we demonstrate that built-in sensor fusion mechanisms were unable to detect GPS spoofing and that our method could detect subtle GPS spoofing using multiple different sensors.