Mitigating GPS Spoofing Threats with Honeywell GPS-Aided Inertial Systems

GNSS-Inertial integration brings great potential to detect and mitigate the effect of erroneous (spoofed) GNSS data. When a trajectory of an airplane diverges from (or is inconsistent with) inertial data, the integrated system may detect this erroneous GNSS trajectory and may be able to maintain navigation integrity by rejecting this data. A GNSS-Aided Inertial System can provide both self-contained detection of a GNSS spoofing event as well as mitigation, where mitigation is hard to achieve globally with other commercial aviation systems relying on good ground system coverage. This paper provides an overview of the newly developed Inertial Spoofing Monitor for aviation grade navigation systems, which was designed to detect multiple simultaneous erroneous (spoofed) satellite measurements. The Inertial Spoofing Monitor was then thoroughly tested, and simulations were performed to evaluate and demonstrate the detection, mitigation, and recovery capability of the spoofing monitor. The performance validation followed the process prescribed by Appendix Q of the RTCA DO-384 MOPS (Minimum Operation Performance Standard). The results show great detection, mitigation, and recovery performance of the developed Inertial Spoofing Monitor, but also indicate constraints regarding the assumed sensor error model.