Enhanced isolation in aperture fed dielectric resonator MIMO antennas for 5G Sub 6 GHz applications

A quad-port dielectric resonator antenna (DRA) is proposed for sub-6 GHz 5G MIMO applications, featuring high isolation, dual-band operation, and enhanced efficiency. The antenna is designed using electromagnetic coupling with a triangular patch to excite the square dielectric resonators (DRs) at targeted resonance modes (TE^x₁₁₁ and TE^x₁₂₁), achieving broadband and polarization diversity. The proposed structure exhibits self-isolation above 20 dB without requiring additional decoupling structures. The use of Alumina (εr = 9.9, tanδ = 0.0001) ensures low loss, high efficiency (88.9% and 93.8%), and strong radiation performance, with peak gains of 9.12 dBi and 8.58 dBi at 3.72 GHz and 4.75 GHz, respectively. The full ground plane and optimized spatial placement further contribute to reduced mutual coupling and improved diversity performance, achieving an envelope correlation coefficient (ECC) of 0.042 and channel capacity loss (CCL) below 0.2 bits/s/Hz. The proposed antenna's measured results align closely with simulations, confirming its suitability for high-performance 5G MIMO communication systems.