Vestigial signal defense through signal quality monitoring techniques based on joint use of two metrics

The open nature of the global navigation satellite system (GNSS) civil signals makes them very vulnerable to counterfeit and ill-intended interferences like jamming and spoofing attacks. Spoofing of GNSS signal refers to the transmission of a counterfeit GNSS-like signal, with the goal of deceiving the receiver, making it compute erroneous navigation solutions. In this paper, an evolved version of the signal quality monitoring techniques is presented where a spoofer detection algorithm is discussed. The quality of the correlation function is assessed through the joint use of two metrics which are based on the ratio metric and a pair of extra-correlators in order to detect vestigial signal presence. The results show that the joint use of two provides advantages in the detection of matched-power spoofer attacks.