Robust Wideband Adaptive Beamforming Based on Focusing Transformation and Steering Vector Compensation

The wideband adaptive beamforming method would deteriorate severely when the desired signal is contained in the training snapshots, especially the mismatched signal steering vector existed simultaneously. Therefore, a robust wideband adaptive beamforming method is proposed based on focusing transformation and steering vector compensation. In proposed method, the received wideband signals are first decomposed into narrow sub-bands. Then, based on the direction of arrivals of signals, the interference plus noise covariance matrix of each sub-band is reconstructed to remove the desired signal and transformed into the reference frequency by the focusing transformation. Subsequently, the mismatched signal steering vector is compensated based on the error vector decomposition and the optimization of output power of adaptive beamformer. Finally, the adaptive weight vector of robust wideband beamforming is calculated based on the minimum variance distortionless response criterion. The effectiveness of proposed method is verified by numerical simulations.