Anti-Spoofing Technique Based on Vector Tracking Loop

Research on the key anti-spoofing technologies is of great significance to resist the increasingly complex threat of spoofing attacks on global navigation satellite system (GNSS) users' application services. The purpose of detection technologies is to detect spoofing attacks and these are currently relatively mature. However, the current mitigation technologies rely on an antenna array or external sensor information, which is costly and poor in practicability. Therefore, we propose a new detection-estimation-correction anti-spoofing technique based on the vector tracking loop (VTL) structure. This technique effectively utilizes the advantages of the VTL structure to construct equivalent noise bandwidth (ENB) detection statistics to detect spoofing attacks. With the design of 51 sets of correlators in the receiver channel for the first time, the method of estimating and correcting code phase delay error by virtual autocorrelation function (VACF) is proposed, and the effective recovery of receiver navigation and positioning solution is realized by the extended Kalman filter (EKF). The spoofing scene tests of the Texas Spoofing Test Battery (TEXBAT) database show that the proposed anti-spoofing algorithm has a detection probability of more than 90% under the condition of a false alarm rate of 0.1%; the alarm time delay is less than 20 s and the time or position deviation is reduced from 600 m to less than 20 m, which has an excellent performance in detecting and mitigating spoofing attacks. The proposed anti-spoofing technique does not need external information and shows a wide range of potential applicability values for receivers equipped with anti-spoofing attack modules.