雷达接收器目标信号波达角优化估计仿真研究

摘要

Target angle measurement accuracy can be improved by the DOA(Direction of Arrival)optimization estimation of target signals for radar receiver.The target signals have characteristics of low SNR,few snapshots and source coherence in complex electromagnetic environment.The DOA estimation accuracy of these signals is poor in existing algorithms.In order to solve this problem,a new autocorrelation matrix estimation method is presented in the condition of that the snapshot contains an integer number of narrow-band signal periods.On this basis,a new method of DOA estimation of coherent signals utilizing the eigenvector corresponding to the maximum eigenvalue of autocorrelation matrix is proposed.Theoretical analysis and simulation show that this method can improve the estimation accuracy of DOA for coherent signals in the situation of low SNR and few snapshots.Simultaneously,under the condition of narrow-band signal and integer number of signal sampling periods,the method of signal cycle accumulation can be applied to any algorithm of DOA estimation based on autocorrelation matrix of receiving data.%雷达接收器目标信号波达角的优化估计,可以提高雷达对目标的角度测量精度,而复杂电磁环境下,目标信号具有低信嗓比、少快拍和信源相干的特点,现有算法对信号波达角的估计精度较差.为此提出了对含有整数个信号周期的窄带快拍数据进行循环累积的自相关矩阵估计方法,并利用接收数据自相关矩阵最大特征值对应的特征矢量,提出了信号循环累积的相干信号波达角估计方法.仿真结果表明,上述方法能够在低信噪比和少快拍条件下提高相干信号波达角的估计精度.同时在满足窄带信号和整周期采样的条件下,信号循环累积的方法可以应用到任一接收数据自相关矩阵的波达角优化估计中.