High-Performance Multiple-Input Multiple-Output Antenna System For 5G Mobile Terminals

Abstract

In this paper, the systematic design of a multiple antenna system for 5G smartphone operating at 3.5 GHz for multiple-input multiple-output (MIMO) operation in smartphones is proposed. The smartphone is preferred to be lightweight, thin, and attractive, and as a result metal casings have become popular. Using conventional antennas, such as a patch antenna, Inverted-F antennas, or monopole, in proximity to metal casing leads to decreasing its total efficiency and bandwidth. Therefore, a slot antenna embedded in the metal casing can be helpful, with good performance regarding bandwidth and total efficiency. The proposed multiple antenna system adopted the unit open-end slot antenna fed by Inverted-L microstrip with tuning stub. The measured S-parameters results agree fairly with the numerical results. It attains 200 MHz bandwidth at 3.5 GHz with ports isolation of (≤−13 dB) for any two antennas of the system. The influence of the customer’s hand for the proposed multiple antenna system is also considered, and the MIMO channel capacity is computed. The maximum achievable MIMO channel capacity based on the measured result is 31.25 bps/Hz and is about 2.7 times of 2 × 2 MIMO operation.

A New CPW-Fed Diversity Antenna for MIMO 5G Smartphones

“…As can be observed from Figure 15 a,b, the sample smartphone antenna prototype offers good quasi-omnidirectional radiation patterns with an acceptable agreement between simulations and measurements [38][39][40]. Table 2 provides a comparison between the presented smartphone array antenna and another reported smartphone array [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. As can be observed, compared with the recently proposed 5G MIMO smartphone antennas with planar and uniplanar structures, our antenna performs better in terms of impedance match and bandwidth, and its clearance size remains at a satisfactory level, as shown in Table 2.…”

“…Several kinds of 5G MIMO smartphone antennas have been put forward recently [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] (see Table 2 for details). However, these MIMO antenna designs either suffer from a narrow frequency bandwidth or occupy a huge space on a smartphone mainboard.…”

Compact Sub-6-GHz Four-Element MIMO Slot Antenna System for 5G Tablet Devices

“…The case with a liquid crystal display (LCD) can also be studied [11], [12]. The LCD made of glass with dielectric constant 7 and loss tangent 0.02 has overall dimensions of 200 mm × 150 mm × 1 mm.…”

“…Simulated antenna efficiencies with an LCD in Figure 22 and measured antenna efficiencies without an LCD in Figure 8 are also very similar. The case with the user's hand holding a mobile device has been studied in [11], [12]. In what follows we will carry out the same study.…”

Low-Profile and Closely Spaced Four-Element MIMO Antenna for Wireless Body Area Networks

“…Thus, for the goal of having higher functionality and reliability, numerous approaches have been lately used to reduce inter-element coupling and hence improve isolation. The achievable data rate throughput in wireless communication would be multiplied and increased within the multiple-input multiple-output (MIMO) system [6,7]. The MIMO approach helps in optimizing the use of the transmission spectrum and power [8,9]; by exploiting MIMO synthesis, additional paths may be utilized in order to improve the link capacity [10,11].…”