Spoofing Monitoring Method Research of GNSS Based on LEO Doppler Measurement

Communication and navigation integration will be a staple of integrated PNT system. LEO satellites, served as an important part of the system, provide support for constructing the future PNT system and improving its service performance. Spoofing is a potential factor to affect reliability of GNSS services, LEO satellites can provide reliable information as independent navigation sources and show good anti-spoofing performance with dual-direction communication links and authentication function, which improve the anti-spoofing performance of the whole system. A LEO-aided GNSS spoofing monitoring algorithm is proposed, constructing a subset-separating detection model based on Chi-square distribution in velocity domain with LEO doppler measurements and GNSS pseudorange rates to detect and recognize spoofed navigation satellites by divided space into subsets. The simulation results show that the novel algorithm can detect and recognize fault navigation satellites effectively, and positioning accuracy after exclusion of spoofed satellites can be ensured. LEO can improve anti-spoofing performance of GNSS observably.