GNSS spoofing detection based on new signal quality assessment model

Abstract

Security exposure in satellite navigation has become a real threat in the face of increasing complexity of the electromagnetic environment. We propose a low-complexity authenticity verification technique by establishing a new model for signal quality assessment. This model is based on total signals energy measurement of both spoofing signals and authentic signals hereafter referred to as the TSEM method. The TSEM method does not rely on the movement of the user receiver or the assumption that all spoofing signals should come from only one transmitting antenna. Simulation results based on GNSS software verify the efficiency of the proposed method. The results show that this method can work well even when the received signal strengths of the spoofing and authentic signals are very close to each other. Also, the performance of spoofing detection gets better with increasing strength of the spoofing signal. This spoofing detection method can easily be applied on GNSS anti-spoofing receivers without changing the architecture of receivers since the characteristics are simple and effective. However, the performance of this method may deteriorate when the code phase differences between authentic signals and spoofing signals are < 1.5 chips and the Doppler frequency differences between authentic signals and spoofing signals are relatively small. But it is difficult to keep the code phases and Doppler frequencies accurately to meet the requirements for the spoofer to avoid being detected. Also, multipath signals effects can also be bad for the robustness of the TSEM method. Thus, the TSEM method needs to be integrated with some suppression technology to restrain or eliminate the multipath signals. Further research is needed to improve the robustness of this method.