Signal-Level Integrity Monitoring Metric for Robust GNSS receivers

This paper deals with the problem of detecting distortions on the received signals of Global Navigation Satellite Systems (GNSS) that may degrade the measurements accuracy and compromise the overall receiver operation. Amongst others, multipath and spoofing are two of the most concerning threats for the robustness of GNSS receivers. These two phenomena have similar effects on the received signal, which can be exploited with the aim of developing a common defence mechanism. The detection process presented herein uses the fact that, in the presence of signal anomalies, the correlation function at the receiver side becomes distorted and loses its symmetry. An assessment on how severe is the effect of this distortion is presented herein. Besides, the proposed scheme is validated with the analysis of real signals simulated with an advanced hardware simulator.