Circularly Polarized Multiple-Input Multiple-Output Dielectric Resonator Antenna for 5G Millimeter-Wave Application

Abstract

A circularly polarized (CP) multiple-input multiple-output (MIMO) dielectric resonator antenna (DRA) is presented in this paper for 5G millimeter-wave (mm-wave) applications. This MIMO antenna consists of two high-order mode CP DRAs, which use the modified cross slots to generate the CP fields. Two complementary split ring resonators (CSRR) are used to isolate the surface current on the metal ground, which can increase the antenna isolation and optimize the axial ratio when each port is excited. The proposed MIMO antenna obtains a simulated impedance bandwidth from 25.41 to 31.18 GHz and an axial ratio (AR) bandwidth (AR < 3 dB) from 25.49 to 29.52 GHz for the 5th generation wireless communication applications. The measured results show that the antenna covers the overlapped bandwidth of 11% and isolation less than −25 dB over the frequency band range. The measured average (peak) gain is 5.84 (6.24) dBic at 26.5 GHz to 29.5 GHz for port 1 and 6.90 (7.27) dBic for port 2.