提出一种相干信号二维波达方向(Direction of Arrival,DOA)估计算法——模式空间波达方向矩阵(Mode-Space DOA Matrix,MS-DOAM)法。算法基于双圆阵,利用模式空间转换将圆阵转换为虚拟双平行线阵,计算虚拟线阵阵元间的互相关信息,构造两个等效协方差矩阵,进而构造波达方向矩阵,对该波达方向矩阵特征分解,利用得到的特征值与特征矢量求得入射信号的仰角和方位角。算法无需二维搜索,实现估计参数自动配对。仿真结果表明,算法在低信噪比和短快拍条件下,估计误差低于虚拟空间平移算法。
Abstraet:A two-dimensional direction of arrival (DOA) estimation algorithm of coherent signals, called Mode-Space DOA Matrix (MS-DOAM) algorithm,is proposed.The algorithm uses mode-space excitation to transform the UCAs into virtual parallel linear arrays.Then,two equivalent covariance matrices are reconstructed by using cross-correlation information of array elements. A new DOA matrix is reconstructed besed on the two matrices. Eigenvalues and eigenveetors are acquired by performing eigenvalue decomposition of the DOA matrix. According to the eigenvalues and eigenvectors with elevation and azimuth information,the DOA of coherent signals could be estimated.The algorithm requires no parameter alignment and 2-D spectrum peak searching.Computer simulation confirms that the proposed algorithm achieved better performance than UCA-VSS algorithm under scenarios of low SNR and deficient snapshots.