外辐射源雷达扩展相消批处理杂波抑制算法的调制补偿

Modulation Compensation of the Batch Version of the Extensive Cancellation Algorithm for Clutter Mitigation in Passive Radar

外辐射源雷达面临严重的多径杂波问题,扩展相消批处理算法(ECA-B)是一种有效的杂波抑制算法,但该算法的分块批处理使得相消距离元内的杂波和目标回波受到调制,导致杂波不能被完全相消而且会产生附加的模糊目标。该文分析了ECA-B算法的调制机理并提出了相应的补偿方法,该方法首先通过载波频偏精估计来补偿杂波调制,然后通过合理选择分块数以避免目标调制或通过估计调制距离元处每块信号的零频分量来补偿目标调制。仿真和实测数据处理结果验证了文中调制机理分析的正确性和所提方法的有效性,完善了该算法的性能。

The passive radar faces a significant problem in multipath clutter, and the Batch version of the Extensive Cancellation Algorithm （ECA-B） is an efficient method for clutter mitigation. However, the clutter and target echoes, whose delays are included in the cancelled range area, are modulated due to the block batch processing in the algorithm, and it results in the clutter residues and false target emergences. The modulation mechanism of ECA-B is analyzed and the corresponding compensation method is proposed in this paper. The basic principle of the method is to compensate the clutter modulation by carrier frequency offset fine estimation and then avoid the target modulation by selecting the block number properly or compensate the target modulation by estimating zero frequency components of every block signal in the modulated range cell. The simulation and real-life data results confirm the correctness of the analysis on the modulation mechanism and the validity of the proposed method, which improves the algorithm performance.