105 / 2019-12-14 07:59:00

Robust Adaptive Beamformer with Weighting Sparse Constraint

adaptive beamformer; sparse constraint; sidelobe suppression; deeper null of interference; ADMM

A sparse constraint on beam pattern has been suggested to suppress sidelobe of adaptive beamforming. To further heighten the performance, a modified Capon spectrum is proposed. In proposed method, the positions of interferences are
distinguished from sidelobe region by capon spectrum and then imposed larger penalty to decrease the array responses at the directions of arrival (DOA) of interference signals. Simultaneously, the modified Capon spectrum gives the minimum penalty on the mainlobe region to keep its shape in existing steering vector error. For a better sidelobe level, we moderately adjust constraint weighting vector step by step. Finally, an algorithm of the alternating direction method of multipliers (ADMM) is suggested to solve the problem efficiently. Numerical examples show the advantages of the proposed method in adaptive beamforming.