Anti-Spoofing Technique Against GPS Time and Position Attacks Based on Sparse Signal Processing

In this paper, we present a cost-effective software-developed Global Positioning System (GPS) anti-spoofing approach against Time Synchronization Attacks (TSAs) and spatial spoofing. We portray two signal-level spoofing characteristics that are predominantly discovered in aforementioned attacks, namely, spoofing profiles and consistency of modifying signals. While the spoofing profiles, which basically describe the inflicting signal shapes affecting the GPS observables, have already been analyzed in our previous research with respect to attacks against timing, this paper still utilizes the idea, yet implements and showcases the applicability of spoofing profiles in position domain. The extension, in fact, brings the idea of joint TSA and spatial spoofing. To jointly consider the time and spatial domains, the pseudorange and range rate equations are linearized with a non-conventional method. An antispoofing technique capable of withstanding TSAs, spatial attacks on single coordinate, and joint attacks is developed for stationary receiver. To validate the proposed approach, we utilize pre-recorded authentic GPS signals in the TEXBAT database for data transmission, which are captured by the Software Defined Radio receiver developed at UTSA. The algorithm is validated in simulations introducing synthetic spoofing and compared against Weighted Least Squares.