Research On Multilateration Method Based On ADS-B Technology

With the gradual opening of the low space airspace,the number of airplanes and unmanned aerial vehicles(UAV)is increasing gradually,more and more problems of air traffic safety have been produced.The scene surveillance as primary measures of protection against construction accidents between aircraft,aircraft and ground vehicles,buildings,not only maintain the airport scene and reduce the pressure of air traffic control departments,but also provide technical support for more effective scenes of aircraft landing safety.Multilateration(MLAT)technology using the existing airport navigation equipment to form MLAT system to realize target location,which has the advantages of high precision,fast refresh frequency,small volume and the characteristics of wide coverage,thus become the main means of large-scale surveillance on the international airport.This paper introduces main surveillance technologies used at present of PSR/SSR,ADS-B,MLAT to show the advantages of MLAT system by contrast.Then the paper introduces and deduces four types of basic principle positioning in MLAT,and deduces in detail three kinds of location algorithm to solve the target position by using the model for time difference of arrival(TDOA)principle,and through a summary of the relevant literature,completes simulation analysis for the positioning accuracy of three kinds of localization algorithm.At the same time,an improved Chan's algorithm is proposed,that is,using the conjugate gradient algorithm to optimize the solving process of Chan's algorithm,and the improved algorithm is simulated,which improves the location accuracy of Chan's algorithm.According to the tracking and prediction of flight trajectory for aircraft,this paper uses genetic algorithm to optimize the BP neural network(GA-BP algorithm)on the basis of the TDOA principle and improves the algorithm,then proposes multiple populations genetic algorithm to optimize BP neural network also named MPGA-BP algorithm,and draws momentum factor into BP to train the network,simulation results and experimental data illustrate the feasibility and effectiveness of the algorithm.Finally,a MLAT experimental platform is built.In the region 2.15.1 ?kmkm,six ground receivers are taken as experimental objects.After receiving and decoding data,the original ADS-B data with GPS time scale is obtained,which provides a lot ofexperimental data for MLAT system.At the same time,we analyze the influence of different distribution modes on the positioning accuracy and complete basic MLAT system experiment.