基于载波域自适应迭代滤波器的无源雷达多径杂波抑制方法

Multipath Clutter Rejection Approach Based on Carrier Domain Adaptive Iterative Filter in Passive Bistatic Radar

在无源雷达系统中,监测通道信号中存在零频和非零频多径杂波,影响目标的检测。时域自适应迭代滤波器(如LMS, NLMS, RLS等)常被用于无源雷达杂波抑制,但这些方法只适用于零频多径杂波。该文针对零频和非零频多径杂波的问题,结合数字广播电视信号的正交频分复用波形特征,提出一种基于载波域自适应迭代滤波器的杂波抑制算法。该算法利用同一载频下含有相同多普勒频移的多径杂波的相关性原理,进行杂波抑制。仿真和实测数据处理结果证明了算法的有效性。

In passive bistatic radar systems, there exists the zero and non-zero Doppler shift multipath clutter in the surveillance channel. The multipath clutter affects the target detection. Temporal adaptive iterative filter such as Least Mean Square （LMS）, Normalized Least Mean Square （NLMS） and Recursive Least Square （RLS） are often used to reject multipath clutter in passive bistatic radar, but these methods are only applicable to reject zero Doppler shift multipath clutter. To solve the problem of zero and non-zero Doppler shift multipath clutter, combined with the orthogonal frequency division multiplexing waveform features of digital broadcasting television signals, a clutter rejection algorithm is proposed based on carrier domain adaptive iterative filter. The algorithm utilizes the correlation of multipath clutter with the same Doppler shift at the same carrier frequency in subcarrier domain to reject the zero and non-zero Doppler shift multipath clutter. Simulation and experiment data processing results show the superiority of the proposed algorithm.