基于局部检测统计量的分布式CFAR检测理论研究

Distributed CFAR Detector Based on Local Test Statistics

本文系统研究了融合中心接收局部检测统计量的分布式CFAR检测技术。在假设局部检测器背景杂波功率水平相同以及不同传感器测试单元之间服从独立同分布的前提下,首先推导了局部采用单元平均(CA)检测器时融合中心的检测概率与虚警概率的解析表达式,在此基础上利用Laplace变换的频域微分性质,将其推广到局部采用其它检测器,获得了普适性的融合方法,可适用于局部采用任意数量、形式的均值(ML)类和有序统计量(OS)类CFAR检测器时的情形,避免了传统的融合中心采用MOS类方法时所需要的局部信杂比相同的假设,实验结果表明了算法的有效性。

This paper studies the design of distributed constant false alarm rate （CFAR） detection systems where the fusing cen- ter receives all of the local test statistics. On the assumption that the clutter power level of the background in each local detector is iden- tical and the returns of the test ceils of different sensors are all independent and identically distributed, we first work out the closed-form expressions of the probabilities of detection （PD） and probabilities of false alarm （PFA） for the fusing center when the local processors use cell average （CA） detectors. By using the differential characteristics of frequency-domain in Laplace transform the universal fusing method is extended to other local CFAR detectors such as maximum likely （ML） and ordered statistic （OS） detectors of any amount or form. This method successfully avoids the assumption of equivalent signal-to-clutter ratio （SCR） in local detectors for traditional fusing center which uses MOS method. The experimental resuhs indicate the validity of the new algorithm proposed in the paper.