基于RDNLMS的机载外辐射源雷达杂波对消

摘要

RDNLMS algorithm is used to cancel Doppler-spreading direct signal and strong echo of airborne passive radar. The transfer function of RDNLMS filter is deduced, based on which a method of non-uniform Doppler extraction is developed to decrease the computing load while minimizing performance loss. With this method, the Doppler of strong echo will be surely extracted hence strong echo will be cancelled efficiently. In addition, the interval of extracted Doppler will not be too large to offer proper suppression for weak echo. Simulations show that when the order of RDNLMS filter is fixed, the performance of non-uniform Doppler extraction will be 2.4 dB better than the uniform one.%该文利用RDNLMS算法对消机载外辐射源雷达多普勒展宽的直达波、强杂波，推导了RDNLMS滤波器的传递函数，在此基础上提出一种非均匀多普勒频率抽取方法，在降低计算量的同时尽可能减小了因抽取带来的性能损失。该方法既能确保强杂波落在所抽取的多普勒频率上从而被有效对消，又能保证抽取间隔不致过大进而使较弱的杂波也得到适当的抑制。仿真实验表明：当对消阶数相同时，非均匀多普勒频率抽取方法比均匀抽取对消性能提高2.4 dB。