Research On Radar Constant False Alarm Detection In Non - Uniform Clutter Background

The CFAR processing radar signal is one of the important research contents in modern radar signal processing, and possesses an indispensability status in automatic radar detection. Although the research on CFAR processing technology has made many progresses, the existing classical CFAR detection algorithm in different environment in general is difficult to get the properties of the equilibrium, and mostly CFAR detectors are facing problems under the non uniform clutter edges and multiple interfering targets environment detection performance degradation problem. Based on the analysis of several typical clutter model, radar CFAR detection technology is studied under the background of non uniform clutter. The main work is as follows:1) Based on the discussion of classic clutter distribution models such as the Rayleigh distribution, Lognormal distribution and Weibull distribution clutter, with Weibull distribution clutter for example, using Zero Memory Nonlinearity (ZMNL) transformation methods generate incoherent and correlated clutter simulation, which lays the foundation for further research work.2) Analyzing the conventional Mean-Level(ML) CFAR and Order-Statistic(OS) CFAR detectors, simulating and comparing the performance in the condition of uniform clutter background, multiple interfering targets clutter background and clutter edge background, offering benchmarks for the non uniform background clutter CFAR detector provides performance evaluation.3) For the presence of clutter edge of non uniform clutter background environment, the paper simulates and analysis MLC-CFAR, VI-CFAR and other CFAR detection algorithm. Aiming at the missed alarm probability increase of VI-CFAR in the clutter edge and detection performance decrease in the multiple interfering targets environment, a multi strategy CFAR (ACSVI-CFAR) detector is proposed. Simulation analysis shows that ACSVI-CFAR detector can improve VI-CFAR in uniform background, CFAR loss and clutter edge control false alarm probability ability. Meanwhile, it has the excellent performance of S-CFAR detector in multiple interfering targets backgroud.4) For unknown number of multiple interfering targets in clutter environment, based on study of the ordered data variability (ODV) censoring algorithm of principle, simulation analysis of the adaptive censoring maximum likelihood constant false alarm rate (ACMLH-CFAR) detector based on ordered data variability (ODV). Aiming at the shortcomings of performance degradation about ACMLH-CFAR detector in the clutter background edge detection, the paper uses the mean value ratio of the VI-CFAR algorithm to improve the performance. The simulation results show that the performance of the improved ACMLH-CFAR is improved in the clutter edge.