An Algorithm for Estimating DoAs of Mixed Signals and Mutual Coupling Error of ULA Based on Alternative Iteration

Based on alternative iteration, an algorithm is proposed to estimate the DoAs of mixed signals and mutual coupling error for Uniform Linear Array (ULA). In the algorithm, utilizing the Toeplitz structure of the mutual coupling matrix of the ULA, a threshold-based method is presented and used to estimate initially the DoAs of the incoherent signals in mixed signals, and then the corresponding mutual coupling error is achieved. On the basis of this, the DoAs of the mixed signals is estimated and the mutual coupling error is updated in an alternative iteration mode. The overall algorithm can achieve the convergence with at most two times alternative iterations. The computer simulation indicates that the algorithm has good performance of DoA and mutual coupling error estimation even with less receive shotsnaps and in lower SNR region.