A Compact High Isolation Four Elements MIMO Antenna System for 5G Mobile Devices

Abstract

A Compact high isolation Multi Input Multi Output Antenna system working on 3.5 GHz (3400 - 3600) MHz is presented for the 5G mobile terminals. Four-antenna elements are employed to construct the proposed MIMO antenna system. These antennas are located over two slim side-edges frame of a mobile device to meet the present trend requirements of slim and full-screen smartphone devices. A modified Hilbert fractal monopole antenna and an I-shaped feeding line construct the antenna element’s front part, while an L-shaped shorted to the system’s ground plane are used to the antenna element’s back part. The overall monopole antenna element’s size printed on the mobile frame’s side edge is (9.72 mm × 5.99 mm) so the desirable antenna miniaturization is achieved. Based on the spatial diversity and self-isolated techniques, high isolation (better than 16.3 dB) is attained by the proposed four-element MIMO antenna system. To assess the proposed antenna element’s performance, the scattering parameters, antenna gains, antenna efficiencies, and radiation pattern characteristics have been evaluated. Besides, the MEGs and ECCs are investigated to appreciate the proposed system’s MIMO performance. Desired antenna and MIMO performances are achieved by the proposed four-element MIMO antenna system so it can be a good candidate for the future 5G mobile handsets.