Modelling and Performance Optimization of Orthogonal MIMO Dielectric Resonator Antenna with Defected Ground Structure

Abstract

This research introduces a high-efficiency multiband MIMO antenna system based on Dielectric Resonator Antennas (DRAs) integrated with a Defected Ground Structure (DGS). Designed to operate at 5.6 GHz, 7.3 GHz, and 8.9 GHz, the antenna supports various modern wireless applications, including Wi-Fi, 5G New Radio (NR), Internet of Things (IoT), Vehicle-to-Everything (V2X) communication, and radar technologies. The antenna is built on an FR4 substrate and employs two pentagonal alumina (Al₂O₃) resonators, which contribute to its high radiation efficiency (~90 %). A DGS composed of rectangular slots is incorporated to minimize surface wave propagation and significantly enhance isolation between elements (|S₁₂| < -35 dB). Compared to conventional MIMO antenna types such as microstrip patches, slot-based, and metasurface configurations the proposed design offers superior isolation and gain (~5 dBi). Additionally, the orthogonal positioning of the resonating elements effectively reduces mutual coupling, reinforcing its suitability for high-performance, next generation wireless systems.