Detection and Mitigation of Spoofing Attacks on a Vector-Based Tracking GPS Receiver

Position solutions provided by GNSS receivers can be completely misled by spoofing attacks. Consequently detection and mitigation of spoofing signals have become one of the important topics within the GNSS community. Some recently published work has addressed spoofing attack on tracking receivers. The work has mostly focused on signal quality monitoring (SQM) techniques to detect spoofing and authentic signals interaction. SQM methods can effectively detect the spoofing correlation peak that is approaching the authentic signal. However, they are not applicable in cases where spoofing attack does not affect the shape of the correlation peak. This situation happens when a spoofer and authentic signals are almost aligned together. This paper provides an analytical approach to investigate the interaction between the authentic and the spoofing correlation peaks during spoofing attacks. Then, a spoofing detection technique based on amplitude analysis of different (namely very early (VE), early (E), prompt (P), late (L) and very late (VL)) correlator branches is proposed. The proposed spoofing detection technique continuously checks the distribution of each correlator output. Spoofing attack is detected if this distribution considerably deviates from that of the authentic signal. A vector based tracking receiver structure has been also employed to bridge the authentic signal outage during the spoofing attack. Data collection has been performed using the simulated spoofing attack by Spirent hardware simulator. Data processing results verify that the proposed spoofing detection and mitigation based on vector based (VB) receiver structure techniques perform well in real world scenarios.