Application of a two-dimensional Butler matrix antenna array for tile-based beamforming

Abstract

This paper proposes a new two-dimensional (2D) Butler matrix antenna array with 16 switching beams for tile-based beamforming. This study fabricated and assembled a 3.5-GHz Butler switching antenna array using multilayer Rogers printed circuit board technology. It adopted a new design concept and layer-by-layer vertical connection architecture. This 2D Butler matrix antenna array does not require long coaxial cables to connect functional circuit interfaces, which is an improvement over the traditional Butler matrix beamforming network (BFN) antenna array and may facilitate considerable reductions in circuit volume and complexity.