A Blind Direction of Arrival and Mutual Coupling Estimation Scheme for Nested Array

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.