Compact two-port UWB MIMO antenna system with high isolation using a fork-shaped structure

A printed ultra wideband (UWB) MIMO antenna system is proposed for portable UWB applications. The MIMO antenna system consists of two semicircular radiating elements on a single low-cost FR4 substrate of a compact size of 35 mm × 40 mm and is fed by a 50-Ωmicrostrip line. A T-shaped slot is etched on the radiating elements to enhance the impedance bandwidth. The proposed antenna system operates over a wide frequency range from 4.4 to 10.7 GHz (almost covering the entire UWB). A fork-shaped structure is introduced in the ground plane to increase the isolation between the antennas. Simulated results of S-parameters of the proposed antenna system are obtained and a high isolation of −20 dB is achieved in most of the band, which is found suitable for MIMO applications.