基于 S 变换的机载雷达稳健空时自适应算法

摘要

Performance of space-time adaptive processing (STAP)is always corrupted by outliers.Hence, a novel robust STAP algorithm based on the S transform (ST)is proposed.It exploits the characteristic that ST spectrum distribution of the outlier is different from the clutter in the time-frequency domain.Firstly,the fast time sequence is transferred to the time-frequency matrix by ST.Some high frequency points of the ST matrix are abandoned to eliminate outliers.Then the remainder of the ST matrix is used to estimate the clutter covari-ance matrix and filter weight.Monte Carlo experiments prove that the proposed algorithm is more robust than other conventional STAP algorithms in non-homogeneous clutter environments.%非均匀杂波环境中的离群点会导致空时自适应处理（space-time adaptive processing，STAP ）性能的下降。针对此问题，该文提出一种新的基于 S 变换的稳健 STAP （S transform-STAP ，ST-STAP ）算法。该算法主要利用杂波和离群点的 S 变换在时频平面上分布特性的不同来实现非均匀杂波的抑制。ST-STAP 算法首先将样本数据对应的快时间序列作 S 变换得到时频分布矩阵，舍弃部分高频分量以去掉离群点的影响，然后用时频矩阵的剩余部分计算相关矩阵和自适应滤波权。蒙特卡罗实验证明 ST-STAP 方法的稳健性和动目标检测性能均优于传统的 STAP 算法。