Design of CPW-fed MIMO Antenna for Ultra-Wideband Communications

This paper presents a compact multiple input multiple output (MIMO) antenna design with good isolation for ultra-wideband (UWB) applications. The proposed antenna contains two identical monopoles that are placed parallel to each other and which are fed by a 50-ohm coplanar waveguide (CPW). The MIMO antenna is fabricated on a low-cost flame resistant 4 (FR4) substrate with an overall size of 36 x 36 x 1.6 mm(3). The designed antenna has a good wideband impedance matching of vertical bar S-11 vertical bar <-10 in the UWB frequency range from 3.1 to 14.9 GHz and a good isolation about 13.7 dB in the whole UWB band. The prototype of the design is fabricated and measurement is carried out in order to validate the simulated results. The proposed antenna exhibits an envelope correlation coefficient (ECC) less than 0.01 and a diversity gain (DG) more than 9.9 dB, which means that the antenna has a good performance and good candidates for UWB applications. (C) 2020 The Authors. Published by Elsevier B.V.