基于相关矢量法L型阵列相干信号DOA估计

针对L型阵列提出了一种基于互相关矩阵的相关矢量(cross correlation matrix correlation vector method,CCM-CVM)重构解相干的波达方向(direction of arrival,DOA)估计算法。为了进一步提高估计精度,在此方法基础上又得到一种改进方法,即CCM-MCVM的方法。该方法基于前后向矢量重构理论,利用阵列互相关矩阵不含噪声的特点,把互相关矩阵的每一个列矢量作为前向矢量,通过对其前向矢量元素进行复共轭变换并颠倒顺序得到后向矢量。利用所有的前后向矢量来重构信号的协方差矩阵并提取信号的子空间,该方法相较于CCM-ESPRIT算法具有损失阵列孔径小,估计精度高的特点。理论分析和仿真结果表明了该方法在低信噪比和小快拍数条件下相较于对比算法具更好的估计性能。

DOA estimation of coherent signals based on correlation vector method with L-shaped array

In this paper, a modified correlation vector reconstruction method (MCVM) is proposed for DOA estimation of coherent signal with L-shaped array .The method is based on the theory of vectors reconstruction. By employing the array characteristics that the cross-correlation matrix is not affected by the additive noise, we use each column vector of the cross-correlation matrix as the forward vector, and the backward vector is obtained by reversing the order of the complex conjugated elements of the forward one. All forward and backward vectors are used to reconstruct the signal covariance matrix from which extract the signal subspace. The proposed method has a larger array aperture and higher estimated accuracy compared with CCM-ESPRIT algorithm. Theoretical analysis and simulation results verify that the proposed method has excellent performance compared with the traditional algorithm, especially in low SNR and the small number of snapshots environment.