直接数据域迭代空时自适应处理方法  

Direct data domain approach with iterative space-time adaptive processing

作　　者：文才[1] 王彤[1] 吴建新[1] 

机构地区：[1]西安电子科技大学雷达信号处理国防科技重点实验室,陕西西安710071

出　　处：《系统工程与电子技术》2014年第5期831-837,共7页Systems Engineering and Electronics

基　　金：国家自然科学基金(61101241;61372133);中央高校基本科研业务费专项资金(K50511020008)资助课题

摘　　要：针对常规空时自适应处理(space-time adaptive processing,STAP)在机载雷达非均匀杂波环境下杂波抑制性能下降的问题,提出一种直接数据域(direct data domain,DDD)迭代空时自适应处理方法。首先利用数据的特殊结构和空时谱的稀疏性引入一种新的迭代自适应(iterative adaptive approach,IAA)空时二维谱估计算法,然后在获得待检测单元空时谱分布的基础上重构无孔径损失的协方差矩阵,最后根据目标信号在空时平面的分布特点,提出一种新的目标剔除算法对协方差矩阵进行修正,以避免目标自相消。仿真实验结果表明,在存在3%阵列误差的情况下,所提方法在旁瓣杂波区的改善因子比传统直接数据域方法高出约10dB、比多普勒平移法高出约5dB。A direct data domain （DDD）approach with iterative space-time adaptive processing （STAP）is proposed to deal with the problem that performance of clutter suppression for airborne radars abtained by con-ventional STAP methods degrades in a heterogeneous clutter environment.Firstly,a new iterative adaptive ap-proach （IAA）for estimation of the spatial-temporal spectrum is introduced according to the special structure of the received data and the sparsity of the spatial-temporal spectrum.Then,the aperture lossless covariance ma-trix for the cell under test is constructed by the estimated spatial-temporal spectrum.Finally,a new covariance matrix regularization method is presented to prevent signal cancelation according to the distribution of the target in the spatial-temporal plain.Numerical examples are given to show that there are about 10dB and 5dB signal to clutter plus noise ratio improvement in the sidelobe clutter region relative to the direct data domain approach and the Doppler wrapping method respectively,even in the presence of 3% array error.

关 键 词：空时自适应处理 杂波抑制 非均匀环境 迭代自适应方法 

分 类 号：TN958[电子电信—信号与信息处理]