A Novel Butler-Enhanced 2 Beam by 4 Element Analog Beamforming Network

A generic agile and theoretically lossless Butler-like multiple beamforming concept and architecture are proposed. Tunable 4-port combining modules are used to focus incoming power from moving directions into beam ports, with optimum gain, while limiting co-channel interference. The resulting beam weights remain close to uniform, for best efficiency in transmit. For demonstration purpose, a simplified 2 beam by 4 element beamformer is modeled and analyzed, demonstrating the high gain and interference limitation capability of this solution. The proposed concept is potentially applicable to hybrid beamforming with multiport sub-arrays for 5G mobile phones and base stations, and for satellite user terminals, with sufficient angular separations of co-channel transmit-receive directions.