非平稳海杂波背景下子带开关相干检测器  

A Subband Switching Coherent Detector in Non-Stationary Sea Clutter

作　　者：时艳玲[1] 

机构地区：[1]南京邮电大学通信与信息工程学院,江苏南京210003

出　　处：《电子学报》2014年第10期1925-1931,共7页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61201325);南京邮电大学引进人才基金(No.NY212018)

摘　　要：海杂波由纹理分量调制散斑分量构成,本文着重研究纹理分量和散斑分量的平稳特性.首先,通过DFT调制滤波器组将海杂波分解到各个子带,提出两种一致性因子分别衡量各个子带海杂波的纹理分量和散斑分量的平稳性,实验结果表明海杂波的非平稳特性主要体现在纹理分量上,强杂波区的纹理分量体现出显著的非平稳性,弱杂波区的纹理分量具有平稳特性.进一步针对海杂波在不同多普勒频率分量上具有不同的平稳特性,将纹理分量的一致性因子作为判断函数,分别使用样本协方差矩阵和归一化样本协方差矩阵估计算法,提出了子带开关自适应归一化匹配滤波(Adaptive Normalized Matched Filter,ANMF)检测器.实测的海杂波数据实验结果表明,子带开关ANMF检测器的性能优于对比算法.Sea clutter is consist of a speckle component modulated by texture.The stationary properties of speckle and texture w ill be researched in the paper.By using the discrete Fourier transform（ DFT） modulated filter bank to decompose sea clutter into low-rate subband signals,two consistency factors are proposed to analyze the stationary properties of speckle and texture of different subband signals,respectively.The results show that the non-stationary characteristics of sea clutter is mainly reflected in texture.Texture is significantly non-stationary in the strong clutter region,and vice versa.Considered that sea clutter in different Doppler frequency has different stationary property,by using the consistency factor of texture as a judge function,a subband switching adaptive normalized matched filter（ ANMF） detector is proposed in the paper,where the covariance matrix estimator is sample covariance matrix（ SCM） or normalized sample covariance matrix（ NSCM）,respectively.The experimental results show that,to detect targets in real sea clutter,the subband switching ANMF detector outperforms competitors.

关 键 词：雷达目标检测 非平稳海杂波 平稳性度量 一致性因子 

分 类 号：TN911.23[电子电信—通信与信息系统]