Ultra-Wideband 8-Port MIMO Antenna Array for 5G Metal-Frame Smartphones

Abstract

A design of an ultra-wideband eight-port multiple-input multiple-output (MIMO) antenna array in a smartphone with an open-slot metal frame for fifth-generation (5G) communications is presented. Each element is fed by a microstrip line with a tuning stub, consisting of a U-slot on the ground plane and an open slot on the metal frame. Each slot element on the ground only occupies an area of 15 ×3 mm. The antenna array can operate in 3.3-6 GHz (S 11 < −6 dB) that is ultra-wide bandwidth for the future 5G communications. The antenna array is manufactured and measured. Measured antenna isolation is higher than 11 dB without any decoupling structures applied. Moreover, measured radiation patterns, antenna efficiencies, and envelop correlation coefficients are also given in this paper. High agreement between the measured and simulated results is obtained, which means that the proposed antenna is promising in engineering application. INDEX TERMS 5G communication, metal frame, MIMO antenna, smartphone, ultra-wideband.

Dual antenna system for metal frame mobile phone applications

“…There are many research articles about antennas for modern mobile phones . The antennas in References are single antenna elements for mobile phones with MFs.…”

“…The antennas in References are single antenna elements for mobile phones with MFs. The antennas in References have two or more antenna elements.…”

“…The antennas in Reference consists of six antennas, two antennas are used to cover the band of 698 to 960 MHz, and the other four antennas are used to cover the band of 1710 to 2690 MHz. The antennas in Reference consist of eight antennas that all can cover 3.3 to 6 GHz at the two long sides of the printed circuit board (PCB). The antennas in References and are the miniaturized antennas applied for MIMO system.…”

“…The antennas in References and are the miniaturized antennas applied for MIMO system. Most of the antennas mentioned above are not suitable for an MF environment except the antennas in References . The elements of the antennas in References 12,17, and 21 are located at the two short sides of mobile phones, respectively, while the elements of the antennas in References and are located at the two long sides, respectively.…”

“…Most of the antennas mentioned above are not suitable for an MF environment except the antennas in References . The elements of the antennas in References 12,17, and 21 are located at the two short sides of mobile phones, respectively, while the elements of the antennas in References and are located at the two long sides, respectively. The three elements of the antennas in Reference are located at the same short side.…”