A Null Broadening Beamforming Approach Based on Covariance Matrix Expansion

摘要

In order to improve the performance of antenna array beamforming in the case of jammer motion, a null broadening beamforming approach based on covariance matrix expansion is proposed in this paper. The covariance matrix of the array is expanded through the Kronecker product of an eye matrix and the sample covariance matrix. The steering vector of the array is also expanded. When the expanded covariance matrix is used for beamforming, more linear constraints can be constructed compared with the original sample covariance matrix, so wider and deeper nulls can be obtained with equal number of array elements, or similar performance can be obtained with fewer number of array elements. Necessary numerical procedures are provided and computation complexity is analyzed. The validity of the proposed approach is verified by theoretical analysis and simulation results.