Efficient DOA Estimation for Coprime Array via Bi-Nuclear Schatten-p Norm Minimization

In this letter, we propose the Bi-nuclear Schatten-p norm minimization (BSNM) for coprime array to achieve the efficient direction of arrival (DOA) estimation. Specifically, BSNM factorizes a large Hermitian Toeplitz covariance matrix as the product of two small matrices, which not only improves the computational efficiency but also captures the low-rank property of the interpolated covariance matrix. This BSNM problem of the Hermitian Toeplitz matrix is then solved by a parallel alternating optimization algorithm. Finally, the recovered covariance matrix is applied to estimate the DOA via the MUSIC algorithm. Numerical simulation illustrates the superiority of the proposed BSNM method over state-of-the-art methods in terms of computational efficiency.