Optimum two-dimensional beamforming employing sum-and-difference technique
Ta-Sung Lee, Tsui‐Tsai Lin · The Journal of the Acoustical Society of America · 1995
A 2-D adaptive beamforming scheme using a quadruplet array is presented. The scheme is developed based on the sum-and-difference technique employed in conventional monopulse trackers. The construction of the proposed beamformer involves a joint linearly constrained minimum variance procedure on the sum-and-difference processors. With the difference beam used as an auxiliary to suppress the desired signal, the resulting sum beam exhibits robustness to pointing errors in acquiring the desired signal. To maintain an accurate look direction, a simple method for desired source localization is developed using beamspace MUSIC. The proposed beamformer working in conjunction with the angle estimator provides a much better solution to 2-D beamforming than the MVDR beamformer, as confirmed by analysis results and numerical examples.