Research On Method Of Target Surveillance Based On Parameter And Channel Optimization In Civil Aviation

The rapid growth of civil aviation sector leads to introduction of considerable amount of disturbance on supervisory signal,communication link blocking and increasing variety of aerial objects.The target surveillance in civil airspace hence becomes more and more difficult.It is urgent to figure out the civil airspace multi-target surveillance problems.The dissertation starts by the cooperative and non-cooperative target surveillance problems.ADS-B technology is adopted to study target location and tracking algorithm in cooperative target surveillance,non-cooperative target surveillance,and the hybrid target surveillance in complex airspace.A Combined Adaptive Kalman Filter(CAKF)algorithm of multi-parameter optimization is proposed to solve the problem caused by the integrity deficiency of surveillance data and the occurrence of outlier values.The algorithm is based on the Current Statistical Model Kalman Filter(CSKF),and with the help of outlier identification,interpolation filter,maneuver frequency and acceleration variance optimization,it implements dynamic tuning of Kalman filter gain,maneuvering frequency and acceleration variance by optimizing the variance of new information,noise variance and velocity estimation bias.Simulations are carried out to show that the proposed algorithm fulfills automatic recognition of outlier values and target track smoothing.The new method achieves target tracking and estimating,and provides higher accuracy of location,compared with the existing CSKF.In order to solve the problem that the current TCAS system and ADS-B system cannot accomplish non-cooperative target surveillance,a new ADS-B channel radar surveillance system based on random BPSK modulation and TOA location model is presented.An ADS-B system-based radar model with one transmitter and four receivers is designed by optimizing ADS-B signal parameters and transmission pulse,and introducing random BPSK modulation.The proposed ADS-B channel radar surveillance system signal is different from the existing target surveillance technology in civil airspace.The location model of ADS-B channel radar based on TOA is studied and its working range is calculated.The result shows that the monitoring range of the designed channel radar for the airliners can reach 8.3 nautical miles,which satisfies the requirement of air-air surveillance.Fast-tracking problem of air-air surveillance objects with unknown initial status by ADS-B channel radar is studied based on particle filter algorithms is stated.Simulations are conducted to show that the new algorithm provides higher convergence rate and positional accuracy than the Extend Kalman Filter(EKF).Based on the aforementioned two research result,a channel-sharing hybrid surveillance system is designed by optimizing the current cooperative surveillance channel parameter and enabling non-cooperative surveillance to solve the cooperative and non-cooperative target surveillance problems in complex environment.By employing the control method of channel time divided occupancy,the thesis comes up with a hybrid surveillance method for both cooperative and non-operative targets.According to the theory of the 3 subsystem in the hybrid surveillance system,the hybrid surveillance problems is transformed into the control problem of channel occupancy time share multiplexing of each subsystem;the channel occupancy and the duty cycle of transmission pulse are formulated in a mathematical way;the minimal control slot and target danger coefficient table are constructed;and finally the hybrid surveillance of cooperative and non-operative targets is implemented.Simulation analysis shows that when the duty cycle of transmission pulse equals to the typical value 1%,and the proposed methods achieves hybrid surveillance of cooperative and non-operative targets.Outfield experiments are carried out using ADS-B emulator to show that the proposed CAKF algorithm can improve the performance of target track surveillance.By conducting infield experiments with ADS-B emulator,and analyzing the duty cycle of transmission pulse,it concludes that control method of channel time divided occupancy is available for the hybrid surveillance of cooperative and non-operative targets.