基于前后向协方差矩阵投影的信源数估计算法

针对均匀线阵的信源数估计问题，提出了一种基于前向-后向采样协方差矩阵正交投影的多目标信源数快速估计算法。该算法将经过酉变换后的前向-后向采样协方差矩阵的列矢量做Gram-Schmidt (GS)正交化，并将正交化后矢量的模值与一个自适应判决门限做比较来估计信源个数。该判决门限根据阵列采样协方差矩阵估计误差的渐近分布特性推导得到。计算机仿真证明了该算法的正确性和有效性。

Estimaton of the number of signals based on orthogonal projection of forward-backward covariance matrix

A fast algorithm for estimating the number of multiple spatial signals with uniform linear array based on forward-backward sample covariance matrix orthogonal projection (SCMOP) is proposed. Firstly, a unitary transform is performed on the forward-backward sample covariance matrix, and then the column vectors of the transformed matrix are orthogonalized via Gram-Schmidt (GS) orthogonalization algorithm. The number of signal sources is estimated by comparing the modulus of the orthogonalized vectors with an adaptive threshold, which is derived from the asymptotic distribution properties of the estimation errors of the sample covariance matrix. Computer simulations are given to illuminate the correctness and efficiency of the algorithm.