A Compact Four-Port Dual-Band DRA for 5G mm-Wave Communication

Abstract

This work presents a compact single-element four-port MIMO dielectric resonator antenna (DRA) for mm-wave applications. The design employs a rectangular dielectric resonator with a central notch to achieve dual-band operation. Four closely spaced ports are arranged around the resonator, where microstrip feedlines excite rectangular slots to couple energy into the DRA. Port isolation is enhanced through the orthogonal arrangement of the feedlines and slots and further improved using defected ground structures and L-shaped metallic strips. The antenna operates over 24.6–31.4 GHz and 37.8–38.7 GHz, with isolation exceeding 10 dB in both bands. The MIMO performance metrics stay within acceptable limits, confirming reliable operation. Overall, the proposed design provides a compact and efficient solution for mm-wave systems.