极化敏感阵列斜投影滤波性能分析

摘要

The output Signal-to-Interference-and-Noise Ratio (SINR) of oblique projection and orthogonal projection filtering based on a polarization sensitive array is investigated. The output SINR formulae of the oblique projection and orthogonal projection filtering under both the ideal and array error conditions are derived. Under ideal conditions, the output SINR is a function of the spatial and polarized matching coefficient between the signal and interference whereas, under the array error condition, it is a function of the Interference-to-Noise Ratio (INR) and the perturbation momentum. The oblique projection filtering obtains the same output SINR as the orthogonal projection filtering under both conditions, but the output SINR of the maximum SINR principle filtering is the best. Further analysis shows that the oblique projection distorts the spatial and polarized properties of noise filtering while maintaining the amplitude and phase properties of the output signal, which are distorted in orthogonal filtering. The simulation results attest the reasonability of the analysis in this paper.%该文研究了极化敏感阵列采用斜投影滤波和正交投影滤波的输出信干噪比(SINR)特性。推导获得了斜投影滤波与正交投影滤波在理想情况和存在阵列误差时的输出SINR计算式：理想情况下输出SINR是信噪比(SNR)、目标与干扰的空域和极化域匹配系数的函数；存在阵列误差情况时输出SINR受信噪比，干噪比(INR)、目标与干扰的空域-极化域匹配系数及误差扰动量共同影响。分析表明，相比正交投影滤波而言，斜投影滤波的输出 SINR没有改善，也不能提高误差稳健性，它们均低于最优输出SINR；正交投影与斜投影输出SINR相同的成因并不一样，正交投影滤波改变了目标的幅相特性，滤波后目标有损失；斜投影滤波改变了输出噪声的空域-极化域特性，放大了输出噪声的功率。最后通过仿真实验验证了理论分析的正确性。