A MIMO antenna array featuring dual wideband and high gain for 5G NR n257/n258/n260/n261 bands applications

This article introduces the development of a Multi-Input Multi-Output (MIMO) antenna array specifically designed for 5G millimeter-wave (mm-wave) communication systems. The suggested MIMO configuration consists of four antenna arrays, each comprising two elements arranged evenly, operating at 26 GHz and 37 GHz with a physical size of 43 mm x 32.5 mm x 0.8 mm using a Rogers RT/Duroid 5880 substrate. The proposed MIMO configuration provides dual bands, with frequency bands extending from 23.8 to 30 GHz (IBW = 6.2 GHz) and 32.5 to 41 GHz (IBW = 8.5 GHz), accompanied by high gains of around 18.5 dB for the first band and 16.4 dB for the second band. The designed antenna also shows broad circular polarization with 3 dB Axial Ratio Bandwidth (ARBW) of 4.75 GHz, ranging from 25.05 to 29.8 GHz. A physical prototype has been fabricated for the proposed 4 port MIMO antenna array and tested to verify the results acquired from simulations. The comparison between simulation and measurement results in terms impedance and radiation parameters such as S-parameters, isolation, gain, axial ratio (AR), efficiency, radiation patterns, and various necessary MIMO metrics demonstrates a strong alignment. This antenna covers various 5G New Radio (NR) application bands such as 28 GHz n257 (26.50-29.50 GHz), 26 GHz n258 (24.25-27.50 GHz), 28 GHz n260 (37-40 GHz) and 28 GHz n261 (27.50-28.35 GHz) utilized across different countries including Canada, Australia, China, France, Germany, India, Italy, Japan, South Korea, United Kingdom, and United States of America.