A New Roust Blind Beamformer Against Array Errors Under Intensive Interferences

Abstract

It is known that the performance of standard Capon beamformer (SCB) can be degraded tremendously when there exists an unknown mismatch between the presumed signal steering vector and the practical one. The mismatch might be caused by the array imperfections such as mutual coupling, gain and phase uncertainties, sensor position perturbation. In this paper, a new blind beamforming algorithm under intensive interferences for arrays having arbitrary uncertainties is proposed. By utilizing the fact that in the presence of intensive interferences the steering vector of the signal of interest (SOI) can be well approximated by an eigenvector of the array covariance matrix, one can obtain an estimate interference-plus-noise covariance (INC) matrix. Thus, a blind beamformer can be achieved by substituting the reconstructed INC and steering vector of SOI back into the SCB. Unlike most of the existing approaches, the proposed method does not need to know the direction of the SOI or the information of the uncertainties. Simulation results indicate that the proposed method is able to provide superior performance compared with existing approaches.