A two dimensional beam scanning array antenna for 5G wireless communications

This paper presents the planar implementation of a two dimensional (2-D) beam steering array antenna with a cascaded 2 × 2 Butler Matrix (BM) as the beamformer. A single layer has been chosen to ensure low cost and ease fabrication. The four input ports of the proposed antenna have the capability of producing four independent directional beam patterns scanning from -18° to 23° at x-y plane and from -20° to 22° at the y-z plane respectively. The radiation efficiency obtained from each of the four ports at the designed frequency are 92.6%, 92.1%, 91.4%, and 87.8% respectively. The maximum antenna gain of 15.1 dBi is obtained at port P1. The proposed antenna has a null free elevation plane and therefore will be suitable for base station application of the proposed fifth generation mobile communications.