Generally, nested array (NA) is susceptible to mutual coupling due to the dense subarray, which seriously degrades the performance. To address this issue, we design an array switching-based scheme to achieve the blind direction of arrival (DOA) and mutual coupling estimation in this paper. Specifically, by exploiting the inherent sparse structural characteristics of NA, we first switch the sparse subarray on to perform initial DOA estimation, which enables to offer the well- performed estimates free from severe mutual coupling effect. Subsequently, the unambiguous angles are determined with low complexity by utilizing the received signal of the whole NA. Furthermore, the contaminated steering vector is reconstructed and a quadratic optimization problem is established to estimate the mutual coupling coefficients. Finally, the estimated mutual coupling matrix is used to re-estimate for refined parameter estimation. Numerical simulations demonstrate the effectiveness and superiority of the proposed scheme via array switching.

nested array; direction of arrival; mutual coupling; array switching