Design and Optimization of a Transparent and Flexible MIMO Antenna for Compact IoT and 5G Applications

Abstract

This work presents an optically transparent and flexible MIMO antenna that features two square patch elements placed in close proximity, aiming to meet the demands of compactness, flexibility, optical transparency, and visual appeal for IoT applications and future 5G wireless communication. The design includes a simple offset feed configuration to achieve the required isolation and impedance matching. It simplifies the process of creating closely spaced transparent MIMO antenna configurations. By optimizing and analyzing this structure, the antenna achieves better isolation and diversity gain performance, even when the patch elements are positioned very close to each other. To achieve optical transparency and flexibility, the antenna uses thin polyethylene terephthalate (PET) material as a substrate, which is a thermoplastic polymer resin from the polyester family. The wired metal mesh parameters for conducting parts of the MIMO antenna and offset position of the feed are carefully optimized to achieve required optical transparency, isolation, impedance matching and radiation performance without any complex decoupling or impedance matching network.

A compact highly flexible two-element wideband MIMO antenna based on modal analysis for 5G wireless applications

“…CMA has been utilized as an optimization technique for the evolution of the proposed decoupling structure. In [3], the authors have proposed a wired metallic mesh with an offset configuration. The antenna has a satisfactory gain value with good MIMO diversity figures and isolation of 19 dB, but the antenna has only a low bandwidth of 150 MHz.…”

“…The above-mentioned diversity metrics are calculated using equations ( 12)-( 17) [3,26]. ECC from the far-filed patterns can be calculated using the equation ( 12)…”

“…In Sub-6 GHz infrastructure, the network quality and channel capacity can be improved with the multiple input multiple output (MIMO) systems with a wider bandwidth and therefore this technology has become a research hotspot of the decade [1]. Recently, an ample amount of MIMO antenna research has been reported in the literature covering the Sub-6 GHz 5G band [2][3][4][5][6][7][8][9][10][11][12][13]. Most of the literature exhibits a trade-off between less bandwidth, gain or higher mutual coupling that hinders its application in realtime MIMO applications.…”

“…However, the gain of the antenna is very low. In [3], a two-element antenna with a conductive metallic mesh and a transparent PET substrate is proposed for IoT applications. The offset feed configuration contributed to an isolation of 19 dB without any decoupling structure, however the bandwidth and the efficiency of the antenna is low.…”