Dual-Port Compact MIMO-DRAs: Exploiting Metallic Sheets to Increase Inter-Port Isolation at 28-GHz 5G-Band

This brief proposes a novel decoupling method based on metallic sheets to improve inter-port isolation in dual-port single-element multiple-input-multiple-output (MIMO) dielectric resonator antenna (DRA) systems. Two different structures, including an H-plane and an E-plane decoupled MIMO arrangement, have been investigated. The exploitation of metallic sheets can significantly impact the electromagnetic (EM) field distribution inside the dielectric resonator (DR) and restrict the strongest portion of the EM energy couple to the nearby slot. As a result, inter-port isolation can be improved significantly. As the single DR element is used and metallic sheets are embedded within the element, no additional footprint is required, making the MIMO antenna arrangements compact and simple. The outcomes convey a maximum enhancement in the inter-port isolation of the H-plane decoupled MIMO arrangement is about 23.45 dB, while that of the E-plane decoupled MIMO arrangement is about 17.08 dB across the operating frequency band.