SemperFi: Anti-spoofing GPS Receiver for UAVs

Features

In SemperFi we introduce Adversarial Peak Identifier (API) that is reponsible for detecting spoofing attack and distinguishing the attacker’s signal from the legitimate GPS signals. Based on the information provided by the API, the LSR synthesizes an appropriate recovery signal that eliminates the spoofing signal using a successive interference cancellation (SIC) technique. For identification of adversarial signals we introduce active spoofing verification that forces the UAV to execute a maneuver in a scenario where an adversary is capable of gradually introducing location offsets without triggering any detection mechanisms. We rely on the auxiliary peak tracking technique that has been shown to be highly effective against stealthy seamless takeover adversaries to initiate the maneuver. SemperFi is designed as a pluggable module that outputs spoofer-free GPS signals identical to legitimate satellite signals. Therefore, SemperFi allows an unmodified COTS GPS receiver to process and generate location and time estimates without any disruption. It can recover from an attack by executing flight patterns less than 100 m in length, recovering the true location within 0.54 s with an accuracy of less than 20 m (in majority of the cases identification maneuver is not required) on popular embedded platforms such as Jetson Nano and Xavier.