关键词: 波达方向, 空间平滑, 相干信号, 非均匀噪声, 秩最小化

Abstract:

Focusing on the problem of poor accuracy and low resolution acquired by the traditional direction of arrival (DOA) estimation algorithm in the cases of the coherent signals and non-uniform noise and based on the spatial smoothing method, a DOA estimation approach via minimizing the rank of the covariance matrix of the received signal is developed. Following the traditional spatial smoothing approach, the covariance matrix of the received signal is multiplied by a certain switch matrix on the left and right sides in the proposed method, respectively, and then the spatial backward smoothing covariance matrix can be obtained. In what follows, the covariance matrix can be reconstructed into a noise-free one by exploiting the low rank property of the smoothing matrix. Finally, the DOA can be implemented by the traditional MUSIC algorithm. Simulation results demonstrate that, compared to the traditional MUSIC, matrix completion based MUSIC (MC-MUSIC) and rank and trace minimization (RTM) algorithms, the proposed method can suppress the non-uniform noise considerably, and improve the DOA estimation performance significantly in the case of the coherent signals.

Key words: direction of arrival, spatial smoothing, coherent signals, non-uniform noise, rank minimization