基于噪声子空间解析形式的快速DOA估计算法

该文针对特殊的信号环境各辐射源信号均值相等且不为零，利用均匀线阵导向矢量的Vandermonde结构，推导出了噪声子空间的解析形式，并以此为基础提出了利用均匀线阵和稀疏平面阵的1维和2维DOA估计快速算法。该算法不需要计算接收数据的协方差矩阵，也不需要任何矩阵分解，因此计算量远小于传统的超分辨DOA估计，而且无论信号之间是否具有相干性，该方法有相同的估计性能。仿真实验表明，在噪声均值为零且快拍数足够的条件下，该方法的估计性能整体上与Root-MUSIC算法相当，而在信噪比较低时性能优于后者。

DOA Estimation Algorithm Base on Analytical Solution of Noise Subspace

For a special signal environment, where all of the sources have identical nonzero mean values, taking advantages of the Vandermonde structured steering vector of the uniform linear antenna array, an analytical solution of null-subspace is educed in this paper. Based on the solution, both of one-dimensional signal Direction Of Arrival (DOA) estimation algorithm with uniform linear array and two-dimensional signal DOA estimation algorithm with sparse planar array are proposed. The algorithm does not involve the covariance matrix calculation and any matrix decomposition, so it is much computational saved than the conventional super-resolution DOA estimation algorithms. Beside that, the novel method works well either the signal sources are coherence or not. The simulation shows that the novel algorithm possesses the same performance with Root-MUSIC algorithm as the whole when the mean value of the noise is zero and the number of snapshots is enough, and it performs better than Root-Music when the Signal Noise Ratio (SNR) is lower.