On the design of a butler matrix-based beamformer introducing low sidelobe level and enhanced beam-pointing accuracy

A novel Butler matrix-based beamformer nearly doubling the number of radiating beams with improved crossover and sidelobe level is presented. This new approach encompasses separate design ideas for sidelobe level improvement and beam-pointing accuracy enhancement, respectively. Explicitly, the number of available beams is almost doubled while the desired angular sector is scanned with radiated power variation of less than 1dB provided that a power control system is enabled.