针对传统MUSIC算法在低信噪比，小快拍数等非理想条件下分辨率下降的问题，提出了改进的基于子空间投影的MUSIC测向算法. 该算法充分利用子空间信息，采用新的特征值校正方法对噪声子空间进行加权，并与加权信号子空间投影进行空间谱合成，得到新的空间谱函数. 搜索函数极大值，就能得到来波方向. 新方法既保
留了噪声子空间算法的高分辨性能，又保留了信号子空间算法的稳定性. 计算机仿真和实测数据表明新方法有效.
Resolution of the multiple signal classification (MUSIC) algorithm decreases under severe environments such as low SNR, small number of snapshots, and incidence from close angles. To deal with the problem, a modified high-resolution direction-of-arrival (DOA) estimation method is proposed. The algorithm
makes full use of information contained in the subspace. By weighting noise subspace with the corresponding revised eigenvalues, a new spatial spectrum is obtained, which is multiplied by the signal subspace projection. By searching the maximum of the spectrum function, the DOAs are obtained. Simulations and experiments confirm that the proposed method can keep high resolution of noise subspace, and improve robustness of the algorithm.
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