To meet the development guideline of 5G mobile communication system, the transmission rate of mobile terminals must reach 1 Gbit / s at any time, place and individual experience. Currently achievable technologies can be divided into Two are the high-dimension MIMO antenna systems below 6 GHz and the second is the high gain array antenna system in the millimeter-wave band.
Since the wavelength of the millimeter wave band is much shorter than the wavelength below 6 GHz, the decay rate of the energy in the free space is significantly faster, and the signal is easily broken due to poor reception when the user holds the device. These physical limitations are Nowadays, one of the major challenges that must be overcome nowadays is the fact that compared with the millimeter-wave frequency band, the current research of Sun Yat-sen University has verified the feasibility of a high-dimension MIMO antenna system below 6 GHz. The system, no matter in general indoor environment, outdoor environment or user hand Grip and other scenarios, the transmission speed can achieve Multi-Gbit / s performance.
The multi-antenna high-dimension MIMO antenna system developed by Sun Yat-Sen University mainly focuses on 3.4 ~ 3.6GHz test frequency band. On the terminal device, the unit also developed the practical design of handsets 8 and 12 antennas. The conception of the configuration is that at the transmitting end And the receiving end, multiple MIMO antennas are configured, and simultaneous data transmission is performed on at least eight receiving channels.
This combination of 5G antenna system and mobile phone practical design research results show that when the phone built-in MIMO 12 antenna, applied to 12 × 8 MIMO system, 256QAM modulation and 100MHz bandwidth, the measured data throughput of about 3.8 Gbit / s, spectral efficiency of about 38 bps / Hz. The experimental results confirmed that the mobile phone with MIMO multi-antenna, can indeed achieve Multi-Gbit / s transmission rate .Although the user hand dual-frequency MIMO 8 antenna and body block , It will reduce the receiver's octet signal to noise ratio, but at 16 QAM modulation and 100 MHz bandwidth, 3.5 / 5.8 GHz dual-band throughput can still be up to about 1.8 Gbit / s
The experimental results show that the high-dimensional MIMO antenna system below 6GHz indeed helps to improve the spectral efficiency and significantly increase the data transmission speed, and the transmission speed can be maintained Multi-Gbit / s when the user holds or body block Performance, and will therefore be a great potential technology to achieve 5G development guidelines.