An Eight-Element MIMO Antenna Covering All the 4G LTE and 5G NR Bands with A 0.5 mm Clearance for Metal-Bezel Mobile Phones

An eight-element MIMO antenna with a 0.5 mm clearance which operates across all 4G LTE and 5G NR bands is proposed in this study for metal-bezel mobile devices. The proposed antenna is composed of eight elements in four parts, the elements in each part are structurally symmetrical. Also, the method of matching, multi-modes, and multi-branches are utilized to extend the antenna bandwidth. The prototype is fabricated and the antenna performance is measured. The bandwidths of -6 dB cover all the 4G LTE bands (0.704-0.960 GHz and 1.71-2.69 GHz) and 5G NR bands (3.2-4.2 GHz and 4.45 GHz). The measured couplings between the eight elements are better than -10 dB. And the measured efficiencies in 4G and 5G bands are 38%-61% and 41%-72%, respectively. The proposed eight-element MIMO antenna with the clearance of 0.5mm covering all the 4G LTE and 5G NR bands is promising for the practical applications.