Robust beamformer based on total variation minimisation and sparse-constraint

Abstract

A sparse beam pattern constraint could suppress the sidelobe of the minimum variance distortionless response beamformer. But the array gains of the practical beam pattern are not in standard sparse distribution but dense in the mainlobe and sparse in the sidelobes. To improve performance, while revising the sparse constraint only on the sidelobe, a total variation minimisation of the whole beam pattern is incorporated to encourage large array gains accumulated in the mainlobe and small trivial array gains gathered in the sidelobes. Simulations demonstrate that performance enhancement is considerable for its lower sidelobe level and deeper nulling for interference, while robustness against the steering angle mismatch is maintained.