两种非参量检测器在非瑞利杂波中的检测性能

Detection Performance of Two Nonparametric Detectors in Non-Rayleigh Clutter

现代高分辨率雷达系统中,杂波分布已不再简单地服从瑞利分布,其统计特性往往无法预先确定,此时针对性较强的参量检测方法就失去了恒虚警的检测能力,因此鲁棒性较强的非参量检测方法已成为一个重要的研究方向。文中针对非瑞利杂波中广义符号(GS)检测器和Mann-Whitney(MW)检测器两种非参量检测器在两种非瑞利杂波中的检测性能进行了仿真分析。选择韦伯(Weibull)分布和对数正态(log-normal)分布为非瑞利杂波模型,详细给出了仿真模拟框图,采用Monte Carlo仿真方法,分别得出了GS、MW及最佳线性参量检测器在Weibull和log-normal杂波对非起伏目标的检测性能曲线。仿真结果表明,GS和MW在非瑞利杂波中的检测性能均优于最佳线性参量检测器,不同的杂波分布具有相同的均值与中值比(ρ)时,两种检测器性能相差不大。论证了增大独立脉冲积累数(M)是提高检测性能的有效手段。

In mordern high resolution radar systems, the clutter distribution isn＇ t a simple rayleigh distribution, and the clutter＇ s statistic characters are unknown. With this clutter, parametric detectors lose the capability of CFAR. So robust nonparametric detectors become very important. In this paper the detection performances of Generalized Sign Test and Mann - Whitney detector under two non - rayleigh clutters are analyzed. The clutter is assumed to be Weibull distribution or to be characterized by a log - normal distribution. The diagram of a computer simulation is given in detail. The curves of the detection performance of GS, MW and optimum linear parametric detector for nonfluctuating target models are given through a Monte Carlo simulation. The result shows that two nonparametric detectors＇ detection performances are better than optimum linear parametric detector＇ s. When the ratios between mean and middle value of different clutters are equal, the differences of the detection performances under different clutters aren＇ t very great. It is proved that increasing the number of integrated pulses can improve the detection performance greatly.