Sidelobe Suppression for Robust Capon Beamforming With Mainlobe-to-Sidelobe Power Ratio Maximization

High sidelobe level is a major disadvantage of the Capon beamforming. To suppress the sidelobe for interference nulling, this letter introduces a mainlobe-to-sidelobe power ratio maximization constraint to the Capon beamforming. Its relaxed convex programming model minimizes the sidelobe power while keeping the mainlobe power constant. Simulations show that the obtained beamformer outperforms the Capon beamformer and sparse Capon beamformer.