A Method for Broadband Shaped Beam Based on Iterative Variably-Weighted Least Squares.

To solve the problem of a great mainlobe gain loss and high sidelobe level in the conventional weighted least squares(WLS) broadband beamforming methods, a novel variably WLS broadband beamforming method based on iterative variably weighted values is proposed. First, the weighted function and reference beam pattern are properly designed to iterativly optimize the weighted values simultaneously in mainlobe and sidelobe areas, and then the minimum sidelobe level is adjusted and the weighted values of beamformer are updated for obtaining the design of approximately invariant frequency broadband beam shaper with sidelobe attenuation. Compared with the conventional WLS broadband beamshaper, a more efficient and effective control over the beamshaper mainlobe gain loss and sidelobe level is achieved, thus improving the frequency invariant property and decreasing the higher sidelobe level. Simulation results demonstrate the validation of the proposed method. [ABSTRACT FROM AUTHOR]