Wideband 3×4 Butler matrix using Wilkinson divider for MIMO applications

Abstract

This paper presents the design and simulation of a broadband 3×4 Butler matrix for the IEEE 802.11 b/g/n and ISM bands. The aim of this study is to develop an antenna array feeding networks for Multiple-Input Multiple-Output (MIMO) applications, based on an asymmetric Butler matrix. The asymmetric structure allows to create a further beam on the array's normal axis, in addition to the same beams which are created by the symmetrical version. The proposed circuit presents a high isolation and wideband features. The circuit can be used for both transmission and reception systems to ensure the Multi-User MIMO (MU-MIMO) service.