GNSS Radio Frequency Interference Mitigation in Collins Commercial Airborne Receivers

Abstract

Nowadays, commercial aeronautical Global Navigation Satellite Systems (GNSS) receivers are more and more exposed to Radio Frequency Interference (RFI) threats from GNSS jammers and spoofers. On commercial aircraft GNSS, receiver outputs, in general, are integrated or cross-monitored with other navigation sensors such as IRS and DME, etc., and, in many cases, the GNSS receiver outputs are used directly by on-board aircraft systems. The advent of modernized dual-frequency and multi-constellation signals will improve the availability and integrity of GNSS receivers in the presence of RFI. To be further resilient to the various types of RFI threats, the airborne GNSS receiver will need to perform additional receiver-based detection/mitigation techniques and should be able to determine position integrity in the presence of spoofers. This paper focuses specifically on two techniques under development that will be incorporated via a field loadable software update to the GLU-2100. The first method, Receiver Autonomous Signal Authentication (RASA), and a second type of technique, Staggered Examination of Non-Trusted Receiver Information (SENTRI). The paper will provide a brief description of the RASA and SENTRI algorithms, followed by results from both simulation and real-world tests. Finally, the limitations of the algorithms will also be provided.

Keywords

• GNSS
• RFI
• anti-spoofing