Design of Wideband Sub-6 GHz 5G MIMO Antenna with Isolation Enhancement Using an MTM-Inspired Resonators

This paper proposes a low-profile wideband multiple-input-multiple-output (MIMO) antenna operated in the frequency of Sub-6 GHz 5G new radio applications. The ENG metamaterial (MTM) structures were used in isolation enhancement. The isolation of the proposed flag-shaped MIMO antenna with MTM achieved high isolation at frequency ranges of 3 - 6 GHz. The lowest transmission coefficient of -40.58 dB at 3.7 GHz. The diversity performances were investigated by the transmission coefficient (isolation), envelope correlation coefficient was less than 0.025 dB, and diversity gain was more than 9.95 dB. Furthermore, the maximum gain was 3.28 dBi at 3.1 GHz. The radiation patterns were a quasi-omnidirectional, the proposed flag-shaped MIMO antenna is suitable for Sub-6Ghz 5G new radio applications.