Design and Analysis of an Eight-Port Dual-Polarized High-Efficiency Shared-Radiator MIMO Antenna for 5G Mobile Devices

Abstract

Nowadays, the MIMO can achieve fifth generation (5G) ultra-high capacity, but it is a great challenge for the smartphone antenna to achieve good isolation, high efficiency, and other performance in limited space. The paper designed and completed an eight-port dual-polarized high-efficiency shared-radiator antenna working in 3.5 GHz (3.4–3.6 GHz) for 5G mobile devices. The two antenna elements are regarded as one building block and share one radiator, and the size of one radiator is 17.1 × 17.1 mm2 (0.02 λ × 0.02 λ, where λ presents the free-space wavelength at 3.5 GHz). The MIMO system consists of four radiators, and the edge-to-edge distance between the radiators on the short side is 31.9 mm (0.038 λ), and the total size of the MIMO antenna system is 150 × 80 × 1.6 mm3 (0.176 λ × 0.094 λ × 0.0019 λ). The antenna uses an orthogonal placement of feed lines to produce dual polarization in the MIMO system, resulting in high isolation without introducing other decoupling structures. In addition, the reason for the high efficiency of the antenna is explained by the common mode (CM) and differential model (DM). Finally, the simulated results are as follows: the isolation is 14 dB; the total efficiency (TE) is 75–85%; the envelope correlation coefficient (ECC) is lower than 0.065; and the gain is 6.5 dB. The prototype is fabricated and tested: the isolation is better than 17 dB, the range of the measured TE is 60–75%, and the ECC is lower than 0.045. In addition, the influence of the human body model on the antenna are also discussed. Overall, the proposed MIMO antenna has a shared radiator with high isolation and high TE, and is more suitable for the current stage of 5G MIMO antenna technology. More importantly, the planar structure block is very simple to build and easy to fabricate on the substrate.

Design a Dual Polarizations MIMO Antenna Based on Decoupling Elements for 5G Smart-Phones

“…The axial ratio (AR) is equal to 0.37 dB. In [39], the authors present a dual-polarized MIMO system for mobile applications. The total MIMO size is 150 × 80 × 1.6 mm 3 printed on an FR4 dielectric substrate.…”

A Compact Dual Band MIMO Dielectric Resonator Antenna with Improved Performance for mm-Wave Applications

“…For further reductions of coupling, the two integrated DRAs and feed structures were placed on opposite sides of the Rogers substrate as demonstrated in Figure 3c. It should be noted that the recommended distance between the DRAs' centres is 0.5λ 0 [28]. The configuration's parameters are listed in Table 1.…”

W-shaped Eight-port Wideband MIMO Antenna

“…The MIMO antenna system has a total size of (150 × 80 × 1.6) mm 3 and four radiators. The final simulated outcomes are as follows: The gain is 6.5 dB; the envelope correlation coefficient (ECC) is less than 0.065, the isolation is 14 dB; and the total efficiency (TE) is (75-85%) [12]. A UWB 8-port MIMO antenna array on a smartphone with an open-slot aluminum frame is proposed for fifth-generation (5G) communications.…”