A Theory of Aircraft Position Verification Using TDOA

Aeronautical surveillance systems, which provide aircraft position to air traffic controllers, are an important infrastructure for safe and efficient flights. One of the next generation systems is Automatic Dependent Surveillance - Broadcast (ADS-B) which requires aircraft to periodically broadcast their own position. Although ADS-B is more accurate than the conventional radars, it is susceptible to avionics failures or spoofing. A practical countermeasure is position verification by Time Difference Of Arrival (TDOA). This paper provides a theory of the TDOA-based position verification for ADS-B. The probability of detection, probability of false alarm, and detection threshold are derived by combining the binary hypothesis testing and the linearization known in the TDOA-based localization. The derived analytical expressions are convenient for analysis and system design.