一种基于重置协方差矩阵的波束形成优化方法

An optimization approach for beam-forming based on reset covariance matrix

低信噪比情况下,针对波束形成方位历程图显示效果较差问题,提出一种重置协方差矩阵的波束形成前置预处理方法。该方法依据协方差矩阵中主对角线元素相比其他元素所含噪声能量差别较大、信号能量基本一样的特点,利用协方差矩阵主对角线邻近元素绝对值对主对角线元素进行重置,降低主对角元素所含噪声对方位历程图的影响,改善方位历程图显示效果。计算机数值仿真和海上实验数据处理结果表明,高信噪比情况下,该方法对方位历程图显示效果无影响;低信噪比情况下,该方法可以很好地改善方位历程图显示效果;该方法同样可以结合其他后置处理技术同时使用,进一步改善方位历程图显示效果。该方法可为改善方位历程图显示效果提供一个参考。

Under the condition of a low signal-to-noise ratio （SNR）,aiming at the problem that the beam-forming bearing/time recording （BTR）display is bad,a pre-processing approach for beam-forming based on reset covariance matrix was developed.With this method,the characteristic that compared with other elements in covariance matrix,main diagonal elements contain more noise and have almost the same signal energy was concerned,then the absolute value of neighboring elements of the main diagonal were used to reset main diagonal elements and reduce the effects of the noise contained in main diagonal elements on BTR.The BTR display was improved.The results of simulations and sea-tests showed that this method doesn’t affect the BTR display effect of high SNR,can improve the BTR display effect at low SNR;and can be combined with other post-processing techniques to further improve the BTR display effect.This method provided a reference for improving the beam-forming BTR display effect.