Experiment Of 28 Ghz Band 5g Super Wideband Transmission Using Beamforming And Beam Tracking In High Mobility Environment

This paper presents some results of experimental trial in high mobility environment for the 5th generation (5G) mobile communication systems using 28 GHz band. In order to tackle rapidly increasing traffic for 2020 and beyond, new radio access network for the 5G mobile communication systems will introduce the use of higher-frequency bands such as spectra higher than 10 GHz to achieve higher capacity and super high bit rate transmission of several tens of Gbps. The target of this experimental trial is to evaluate the effectiveness of using 28 GHz band with super-wide bandwidth of 800 MHz for 5G mobile communication systems. To compensate large path-loss in higher frequency, the beamforming based on Massive multiple-input multiple-output (MIMO) is one of promising techniques and can be combined with spatial multiplexing of multiple data streams to achieve much higher capacity. In addition, to support the mobility of mobile station (MS), beam tracking technique is important. In this paper, we show some results of the outdoor experiment of Massive MIMO beamforming combined with spatial multiplexing in high mobility environment with MS speed of up to 60 km/h by using prototype system with base station (BS) having 96-element array antenna and MS having smartphone-shape antenna with 8 elements. We also show that maximum throughput of 3.77 Gbps can be achieved with MS speed of 60 km/h by using beamforming with 2-stream multiplexing and beam tracking.