“…Compared to conventional subspace based methods, sparse representation based DOA estimation methods have been attractive since they can provide higher resolution and require fewer samples [6], and many effective sparse representation based methods have been proposed. The greedy methods [7,8] require the prior information of source number and are sensitive to the noise, and the l 1 -norm based algorithms, such as the l 1 -norm singular value decomposition (l 1 -SVD) method [9], sparse recovery using weighted subspace fitting (SRWSF) method [10], sparse representation of array covariance vector (SRACV) method [11], and sparse iterative covariance-based estimation (SPICE) method [12], can reduce the sensitivity to noise and estimate the angles via convex optimization. However, these methods discretize the whole spatial range into a grid, which will result in performance degradation when the sources are not exactly located on the grid, i.e., the grid mismatch problem [13].…”