Wideband Eight-Element MIMO Antenna System for 5G FR1 Mobile Terminals

Abstract

In this paper, a broadband antenna system for multiple-input multiple-output (MIMO) applications in 5G FR1 mobile terminals. The MIMO design consists of eight L-shaped coupled slot antenna elements based on stepped impedance resonators (SIRs) that can generate resonances to achieve wide operating bandwidth. The simulated results of the MIMO system show a -6 dB wide impedance bandwidth of 47% ranging from 3.25 to 5.2 GHz and inter-element isolation level of greater than 12 dB have been obtained for each antenna element with an envelope correlation coefficient (ECC) below 0.05 providing a reliable anti-interference for the MIMO antenna system. In addition, the simulated total efficiencies are higher than 50% across the 5G NR bands; n77 (3.3-4.2 GHz), n78 (3.3-3.8 GHz), and n79 (4.4-5 GHz).