Combined Constrained Adaptive Sum and Difference Beamforming in Monopulse Angle Estimation

Motivated by beam distortions in multiple interferences environment, we propose a novel combined constrained method for adaptive sum and difference beamforming in monopulse angle estimation. By optimizing the adaptive weights of sum and difference beams jointly, the restriction on the degree of freedom to determine the adaptive sum or difference weight is evenly distributed to all weights. The constraints of array gain and monopulse ratio curve are utilized to avoid beam distortion while nulling the interferences. Simulations of the proposed algorithm have been provided, which show a significant improvement in beamforming and angle estimation performance compared with the conventional constrained adaptive monopulse algorithm.