A flexible CPW-fed tri-band four-port MIMO antenna for 5G/WIFI 6E wearable applications

Abstract

This paper introduces a novel flexible tri-band four-port Multiple Input Multiple Output (MIMO) antenna with coplanar waveguide (CPW)-fed for modern 5G/WIFI 6E wearable applications. The proposed antenna operates in three frequency bands by using an etching of rectangular monopole with inverted U-shape slot and a L-shape branch. The prototype of the design is manufactured on flexible Liquid crystal polymer (LCP) substrate with a miniature size of 56 mm × 56 mm × 0.1 mm. The presented antenna operating bands are 2.54–3.56 GHz, 4.28–4.97 GHz and 5.37–8.85 GHz, which can cover Chinese 5G standards n78 (3.4–3.5 GHz), n79 (4.8–4.9 GHz) and WIFI 6E (5.945–7.125 GHz) band. The isolation of the MIMO antenna is higher than 20 dB over whole operating bands by loading a crossed branch with two circular rings. Moreover, the significant performance parameters of the designed MIMO antenna are evaluated, including gain, efficiency, radiation pattern, ECC, DG and TARC. At the same time, the bending test and human test of the flexible antenna are studied in this article. All simulate and measured results demonstrate that the designed tri-band four-port MIMO antenna is promising for 5G/WIFI 6E wearable applications.