ASTAR-ASP: ADS-B Signal Transmission Authenticity Reckoner with Advanced Signal Processing

Under a previous AFRL project, SSCI developed an onboard anti-spoof solution which uses Received Signal Strength and Doppler Shift from received ADS-B reports to detect spoofed signals based on observed inconsistencies between the false and expected behaviors of neighboring aircraft. SSCI’s work resulted in the development of the ASTAR (ADS-B Signal Transmission Authenticity Reckoner) technology, which was evaluated through simulations and hardware tests with the insertion of synthetic spoofed signals. Previous work also revealed that there are non-negligible numbers of false alarms and missed detection, some but not all of which could be reduced by ownship maneuvers. In the current project, our team consisting of SSCI and Georgia Tech, will implement an approach that improves ASTAR performance and minimizes false alarms and missed detections by: (i) Improving path-loss models by comparing performance achieved using Rayleigh, Rician and Two-Wave with Diffuse Power fading distributions and selecting the best solution (or a combination of them) for the Phase II developments; (ii) Accounting for co-channel interference using effective outlier rejection techniques; (iii) Studying the ways in which ownship maneuvering can disambiguate symmetrical paths and other ambiguous cases; and (iv) Processing and separating ADS-B signal broadcasts arriving from dual antennas available in some aircraft. Phase I of the project will focus on the enhancements and performance evaluation of the ASTAR-ASP (ASTAR with Advanced Signal Processing) technology, while in Phase II a full prototype of a reliable anti-spoof technology will be developed, tested through simulations and hardware tests, and demonstrated through flight testing prior to being delivered to the Navy. Follow-on projects will focus on the transition of the ASTAR-ASP technology to Navy and DoD platforms and commercial aircraft.