Sub-6 GHz Dual-Band 8 × 8 MIMO Antenna for 5G Smartphones

Abstract

In this letter, a dual-band 8×8 MIMO antenna that operates in the sub-6 GHz spectrum for future 5G multiple-input multiple-output (MIMO) smartphone applications is presented. The design consists of a fully grounded plane with closely spaced orthogonal pairs of antennas placed symmetrically along the long edges and on the corners of the smartphone. The orthogonal pairs are connected by a 7.8 mm short neutral line for mutual coupling reduction at both bands. Each antenna element consists of a folded monopole with dimensions 17.85×5 mm 2 and can operate in 3100-3850 MHz for the low band and 4800-6000 MHz for the high band (|S11| <-10 dB). The fabricated antenna prototype is tested and offers good performance in terms of Envelope Correlation Coefficient (ECC), Mean Effective Gain (MEG), total efficiency and channel capacity. Finally, the user effects on the antenna and the Specific Absorption Rate (SAR) are also presented. Index Terms-Dual-band, mutual coupling, multiple input multiple output (MIMO), smartphone antenna, SAR.

Evaluation of Development Level and Technical Contribution of Recent Technologies Adopted to Meet the Challenges of 5G Wireless Cellular Networks

“…Within this framework, a simple, low-profile, compact, dualpolarization, low-cost and suspended patch antenna has been designed to operate in a 3.3-3.8 GHz band used for a 5G base station with a gain of 8.95 ± 0.25 dBi [34]. In [29,35], a Sub-6 GHz dual-band 8 × 8 MIMO antenna and Sub-6 GHz 5G NR broadband eightantenna array have been designed, respectively, for 5G smartphones. Unlike this antenna consisting of a monopole operating in 3.1-3.85 and 4.8-6 GHz for the low band and the high band respectively, another dipole frequency-reconfigurable antenna has shown two resonant modes centered at 3.5 and 5.5 GHz or, to be more specific, two bandwidths that are 2.89-4.07 GHz and 5.1-6.19 GHz [36].…”

“…The technical justification for this choice lies in the fact that the main gains, in terms of the performance and efficiency of 5G, are based on the portions of the spectrum that are around WiFi [34]. Therefore, service providers can take advantage of frequencies below 6 GHz as a new exploitable spectrum, ensuring wider channels and better latency [29][30][31][32][33][34][35]. However, the major problem of this frequency band is that a large part of its spectrum is in free use and that the interference problem caused by the multitude of users must be solved.…”

A Quad-Port Dual-Band MIMO Antenna Array for 5G Smartphone Applications

“…Dual-band four-port MIMO antenna can expand system capacity and realize multi-mode communication. To minimize the unwanted mutual coupling, various isolation techniques have been reported in recent years [3][4][5][6][7][8][9][10][11][12][13][14]. The rectangle slots of the defected ground plane and two rectangular microstrip lines are employed to decrease the mutual coupling in [3].…”

“…An inverted-F antenna is used to reduce the mutual coupling of antenna elements [7]. Other decoupling techniques have also been presented, such as using a short neutral line [8,9], high-pass filter [10], pattern diversity [11], self-decoupling [12], defected ground structure [13], and metamaterial structure [14].…”

Design of 10 × 10 Massive Mimo Array in Sub-6 GHZ Smart Phone for 5g Applications

“…In 4G Long Term Evolution (LTE) networks, the conventional 2 × 2 MIMO arrays were used, but it cannot afford high data rates. Therefore, 6 × 6 MIMO, 8 × 8 MIMO, 10 × 10 MIMO, or 12 × 12 MIMO arrays are currently necessary [8,9]. There are three commonly used bands, LTE 42 (3.4-3.6 GHz), LTE 43 (3.6-3.8 GHz), and LTE 46 (5.15-5.925 GHz) in 5G.…”