A Compact Wideband Printed 4 × 4 MIMO Antenna with High Gain and Circular Polarization Characteristics for mm-wave 5G NR n260 Applications

A compact MIMO antenna with circular polarization, high gain, wide operating bandwidth, and a compact size is designed and suggested for mm-wave 5G applications. The propounded MIMO configuration contains four patch elements of similar geometries in 4 × 4 arrangement with individual E-shaped partial ground planes. The desired range of wide operating band with circular polarization, high gain, and high isolation has been achieved by modifying the structure of each single antenna element by integrating circular and semi-circular shaped slots in presence of rectangular slots loaded partial ground planes. The suggested MIMO antenna has been fabricated on a 1.67 mm thick Rogers RT/duroid 5870 substrate of 31.5 × 38.5 mm 2 . The fabricated and tested prototype of the suggested antenna verifies the simulation results. The suggested MIMO configuration offers a wide bandwidth of 8.1 GHz (34.4–42.5 GHz), high peak gain of about 18.5 dB and isolation of ≤−16 dB for the full working range. Besides, the presented antenna is circular polarized. This property allows the proposed antenna to emit the electromagnetic waves with a rotating electric field which allows the signal to propagate in different directions, providing better coverage and reducing the impact of signal polarization. The proposed antenna exhibits a standard MIMO performance by offering attractive diversity parameters. The proposed MIMO antenna is appropriate for 5G NR frequency band n260 (37–40 GHz) covering the allocated bandwidth requirements of different countries including UK (37–40), USA (37–37.6), Canada (37.6–40.0), and Australia (39 GHz).