Research On LFMCW Radar Constant False Alarm Algorithm

The problem of constant false alarm rate(CFAR)in radar target detection is one of the inevitable problems in the field of radar research.In recent years,the research of CFAR processing technology has become a key research project in radar signal processing,especially in the radar target recognition.Although the CFAR processing technology has been widely used,its performance in the non-uniform background is not stable enough.Especially with the development of high-resolution radar,the detection performance of CFAR processing technology under intensive targets still needs to be improved.This paper started from the classic theory of CFAR,studying several constant false alarm algorithms with better performance under multiple objectives while improving variably trimmed mean(VTM)-CFAR algorithm and its detection performance under multiple targets.Meanwhile,the algorithm of the linear frequency modulated continuous wave(LFMCW)radar was used to verify the measured recovery data,and a good result was obtained.To begin with,this paper studied the theory of radar signal detection and the basic theory of CFAR,analyzing the clutter and target models,detection methods,binary hypothesis tests,and Neyman-Pearson(N-P)optimal detection criteria.Also,the basic model of constant false alarm detector and commonly used performance analysis indicators were analyzed.Then several classic CFAR detectors were studied.Principles and mathematical models of the mean CFAR detectors and ordered statistics CFAR detectors were analyzed.Next,based on the theoretical derivation results,simulation experiments were performed on these CFAR detectors,and the detection performance of various methods in different background environments was analyzed and compared,offering future reference to other CFAR detectors.After that,for multi-target situation,the modified trimmed mean(MTM)-CFAR detector with automatic screening technology and the VTM-CFAR detector with adaptive processing technology were studied in a key manner.By comparing with the TM-CFAR detector,the detection performance of MTM-CFAR in different backgrounds was analyzed theoretically and experimentally.Likewise,theoretical research and simulation performance analysis of VTM-CFAR detector were carried out and compared with the performance of ordered statistics(OS)and trimmed mean(TM)detectors,thus further verifying the performance advantages.Combining with previous research results,a generalized variably trimmed mean(GVTM)-CFAR method is proposed and its basic model is introduced.Through simulation experiments,its good detection performance in multi-target environment was compared and analyzed.The measured data of the millimeter-wave radar of the LFMCW system were used to compare and verify the performance of the CFAR detectors studied in this paper.Finally,the author summarizes the work of the full paper and discusses the insufficiency of the research in the paper,while giving prospects to the future research.