Research On Fraud Prevention Of ADS-B Based On TDOA/TSOA Location Method

Automatic Dependent Surveillance-Broadcast(ADS-B) system is a key technology in the new navigation system of ICAO. However, ADS-B system is an open, self-monitoring framework, so the security challenges can not be ignored. Therefore, appropriate measures should be adopted to identify the aircraft position provided by ADS-B message.Through the analysis to the signal of ADS-B, a new hybrid location method is proposed by combining TDOA and TSOA to obtain the real space location, identify the spoof target by comparing with the location data in ADS-B message. For the new TDOA/TSOA location method, a appropriate algorithm has been proposed. When it comes to the location effect of airspace, GDOP is calculated to judge better positioning method more intuitive. By changing the position of all ground stations and flight level of airplane, research on the effect it made to location accuracy. The specific arrangements are as follows:1. Research on the composition and principles of ADS-B system, compare and analyze optional data link technology.2. Analyze 1090 ES signal and characteristics of ADS-B message, simulate the identification and simulation of 1090 ES data link technology.3. Research on the time synchronization method, firstly study on the time synchronization method in ground stations, study on the method between ground station and GPS.4. Study on the TDOA/TSOA location method and solution algorithm. Based on the target location method of TDOA, obtain the fast solve algorithm to the TDOA/TSOA method.5. By calculating GDOP of a large area, evaluate the influence of each ground station to the entire system. And evaluate the location ability to each point of a large area.The results show that the new hybrid positioning algorithm has a better performance than traditional TDOA location positioning method. By using this method to get the real position of aircraft, can achieve the purpose of anti-fraud.