GNSS Spoofing Detection and Exclusion by Decomposition of Complex Cross Ambiguity Function (DCCAF) with INS Aiding

Abstract

In this paper, we present a methodology for detecting and excluding spoofed Global Navigation Satellite System (GNSS) signals by decomposing Complex Cross Ambiguity Functions (CCAF) into their constitutive components. Building on previous work in [1] and [2] utilizing CCAF decomposition and inverse Receiver Autonomous Integrity Monitoring (RAIM), we integrate CCAF decomposition with an inertial sensor in dynamic environments [3]. This integration enables us to identify and exclude spoofed signals, ensuring continuous tracking of the authentic signal for navigation. The method is effective in spoofing scenarios that can lead to Hazardous Misleading information (HMI) and are difficult to detect by other means. It can identify spoofing in the presence of multipath and when the spoofing signal is power-matched with offsets in code delay and Doppler frequency that are close to the true signal. Using the proposed approach, spoofing can be identified at an early stage within the receiver for dynamic users.