Self-Calibration of Mutual Coupling for Non-uniform Cross-Array

Abstract

Based on the non-uniform cross-array, a self-calibration algorithm is proposed to simultaneously estimate the angle of the impinging signal and the mutual coupling error. Firstly, the mutual coupling matrix of the non-uniform cross-array is divided into two parts: the mutual coupling matrix in non-uniform linear array and the mutual coupling matrix between non-uniform linear arrays. Then, the partitioned mutual coupling matrix is decomposed into the sum of several matrices with special characteristics. Thus, the decoupling of angle and mutual coupling coefficients is realized conveniently, so as to estimate the angle of the signal and mutual coupling coefficients. The proposed algorithm does not need auxiliary sources or prior information of the mutual coupling matrix. Moreover, it can reduce the search dimension, and hence, the amount of computation. Theoretical analysis and simulation results show that the proposed algorithm has improved angular resolution and it can estimate the mutual coupling error coefficients precisely. Hence, it can effectively solve the mutual coupling problem for the non-uniform cross-array.