Speaker
Description
Automatic Dependent Surveillance–Broadcast (ADS-B) Mode S messages transmitted at 1090 MHz facilitate aircraft self-reporting telemetry data such as callsign, coordinates, bearing, velocity, and altitude to ground stations. The ADS-B protocol uses a preamble followed by a pulse-position modulated (PPM) data sequence that is simple to demodulate but lacks security features such as encryption, so that messages be easily falsified — causing a risk to aeronautical safety. There are several low-cost methods of verifying ADS-B messages to ensure that they are not falsified, one of which is by measuring the Doppler-shift of the carrier signal over time against what would be expected as predicted by a given telemetry. This presentation discusses an undergraduate research project that aims to investigate the feasibility and benefits of implementing an ADS-B decoding and carrier frequency estimation algorithm on a field-programmable gate array (FPGA), which would then interface with a central processing unit (CPU) within a software-defined radio (SDR.)
