利用信号相位匹配原理抵消相干干扰的性能分析

首先介绍了三元阵的信号相位匹配原理,根据该原理得出信号相位匹配原理提取期望信号的条件;然后研究了利用信号相位匹配原理抵消相干干扰的性能,分析了干扰谱幅度起伏对信号相位匹配原理的影响,推导了干扰谱幅度起伏时提取出期望信号误差的表达式;接着指出基阵接收到的随机噪声可以等效为干扰频谱的起伏;最后根据通常基阵的阵元都大于三个的这一实际情况,提出两种充分利用基阵冗余阵元来减小随机噪声影响、提高抵消干扰性能的方法:三子阵法和最小二乘法。仿真结果证明,三子阵法和最小二乘法的性能远高于三元阵法;最后指出三子阵法运算量小于最小二乘法,但三子阵法适用于均匀线阵列,而最小二乘法适用于任意阵型。

Performance Analysis for Principle of Matched-Phase of Signal in Coherent Interference Suppression

First,the principle of matched-phase of signal of three sensor array is introduced,and the formulae of extracted signal are derived.Then,the performance of principle of matched-phase of signal in coherent interference suppression is analyzed.The effect caused by fluctuation of interference spectrum amplitude on the principle of matched-phase of signal is studied,and the formulae of relative error of extracted desired signal are derived when interference spectrum amplitudes are fluctuant.Again,the viewpoint is presented that the addictive noise can be viewed as the fluctuation of interference spectrum amplitude.Finally,based on the fact that the number of practical array elements is commonly more than three,two methods,three sub-arrays and least square method,are proposed to improve the performance of principle of matched-phase of signal by exploiting redundant elements of array.Simulation result shows that the performance of three sub-arrays and least square method is much better than that of the three sensor array.Also,a conclusion is given that the computation load of three sub-arrays is less than that of the least square method,but the three sub-array method is applicable to the uniform line array and the least square method is suited to arbitrary array.