A Broadband MIMO Antenna Array with Low-Profile Slit Resonators for Sub-6-GHz 5G Mobile Communications

This study presents an 8×8 multiple-input, multiple-output (MIMO) antenna array specifically designed to meet the demands of 5G cellular handheld devices. The antenna features a distinctive configuration, utilizing low-profile inverted T-shaped slits that are fed by rectangular microstrip lines arranged in two rows on opposite sides of the board (four resonators on each side). The investigated MIMO antenna array offers a broadband impedance bandwidth with dual-resonance functionality, operating efficiently from 3.4 GHz to 4.2 GHz. The design delivers excellent performance in key characteristics such as S-parameters, efficiency, gain levels, and radiation patterns. In addition, the configuration of the CPW-fed resonators allows the proposed design to function as two distinct beam-steerable arrays, delivering high-gain radiation at various angles, thus making it suitable for deployment in 5G cellular networks.