Direction-of-Arrival Assisted Sequential Spoofing Detection and Mitigation

Abstract

The paper presents several novel techniques for detection of spoofing/meaconing signals using the direction-of-arrival (DOA) measurements available in a multi-antenna navigation receiver. The detection is based on comparison and statistically testing of the measured DOAs against the expected DOAs. The expected DOAs are computed in the receiver using the almanac and ephemeris. The attitude of the antenna array is assumed to be unknown and therefore has to be estimated as part of a joint spoofing detection/estimation problem. It is shown that the statistics of the DOA estimation error for a signal heavily depends on the elevation of the relevant satellite in the local antenna coordinate system. Therefore, an extended technique for joint spoofing detection and attitude estimation is proposed which incorporates signal and elevation specific statistical information about DOA errors. The performance of the new approach is analyzed through simulations. An extension of the developed snapshot based approach to a sequential approach is proposed. It is shown that new sequential techniques offer great potential for increasing the performance of joint spoofing detection and attitude estimation compared to snapshot based techniques while at the same time the complexity can be significantly reduced.