Metamaterial Inspired Quad-port Multi-Antenna System for Millimeter Wave 5G Applications

Abstract

This work presents a symmetrical quad-element Multiple-Input Multiple-Output (MIMO) antenna that uses a feasible band for 5G millimetre waves at 38 GHz. The main radiator is a patch antenna with a rectangular shape, and the frequency it operates at is 38 GHz. Etching a three-element split-ring resonator (SRR) metamaterial unit cell onto the normal patch radiator allows for widening the resonance over the desired operating band. The suggested MIMO antenna is built on a Rogers RT5880 substrate material that measures 15 x 15 mm2, has a thickness of 0.8 mm, and has a dielectric constant of 2.2. The results of the measurements show that the antenna is capable of covering a frequency range from 37.3 to 39.3 GHz and can also achieve an inter-port isolation of greater than 20 dB between the antenna elements across both bands without the use of a complex decoupling structure. These are the results that were obtained when the antenna was tested. An equivalent circuit diagram of the electrical responses of the antenna is also presented to get insight into the proposed antenna. This schematic makes use of lumped components. The diversity performance parameters that were analysed provide an envelope correlation coefficient that is less than 0.005, and a channel capacity loss that is less than 0.35 bits/s/Hz. All of these results fall well within the parameters that are considered acceptable norms. The findings provide evidence that the design is workable for the transmission of millimetre waves at 5G speeds.