Study On Detection Method Of Distributed Target For Terminal Guidance Radar

With widely application of high resolution radar technique in precision guidance weapons, the theoretical detection of distributed target for radar seekers has become more and more arrestive in radar field. In three kinds of representative application of terminal guidance radar, which are antiaircraft, anti-naval-ships and antimissile, this dissertation studies detection of target distributed in time domain or frequency domain in noise or clutter.In chapter 1, the background and significance of the dissertation are discussed firstly. Then the current status of the study on detection of distributed target is summarized; the framework of optimum detection is set up; the problems of detection in terminal guidance are analyzed. At the end of this chapter, the main works and the structure of the dissertation are outlined.In chapter 2, detection of distributed target in Gaussian background is studied. At first, the relationship between the distribution of scattering centers and detection method based on range profile's energy integration or binary detector is analyzed theoretically. To resolve the problem of collapsing loss, an improved method is proposed. To design optimal bianary detector, the usual principles and fit experiential formula of optimal parameters are acquired. Finally, in the background of antiaircraft terminal guidance radar, a new detector for distributed target based on estimation of range profile's verge is proposed. The results of experiments show that the performance of detector based on range profile's energy integration is improved greatly.In chapter 3, the problem of detecting distribution target for coherent radar in ompound-Gaussian clutter in the background of anti-naval-ships terminal guidance is studied. Firstly, algorithms of detection based on GLRT are summarized, and how mismatch of Doppler steering vector influence the performance of GLRT is analyzed. Then robust detectors are proposed in the condition of unknown Doppler steering vector. The results of experiments with the theoretical and the real data show the efficiency of the detectors.In chapter 4, the problem of detecting distributed target in K-distributed clutter is studied for frequency agility radar in the back ground of anti-naval-ships terminal guidance. Since the frequency agility radar is incapable of Doppler process, optimum binary detector in single profile and optimum two-stage binary detector based on advance process of shift in profiles are proposed. The performance of detectors for different length of targets and different shape parameters of clutter is analyzed in detail. Finally, the usual principles and fit experiential formula of optimal parameters are acquired, which have great theoretic guidance for the real project. The results of experiments with the theoretical and the real data show the efficiency of the detectors. In chapter 5, detection of target distributed in frequency domain is studied in the background of antimissile terminal guidance radar. Firstly, the principle and the conditions of frequency profile modeling are analyzed. In the condition of frequency profile modeling, the formula of acceleration is achieved and the signal model is modeled. Then the problems of detection based on frequency profile modeling in frequency domain are analyzed in detail. Finally, a new method, which is called multi-channel detection algorithm of distributed target based on modified Relax, is proposed. And the results of simulation prove the efficiency of the method.Chapter 6 is the summary of the dissertation. The future work to be further researched is discussed also.