NTT DOCOMO verified the stable operation of 5G, including handover between base stations and the transmission of high-definition video data, aboard JR East's ALFA-X1 Shinkansen test train running at 360km/h. The trials confirmed that it will be possible to ensure stable mobile communication environments on high-speed trains for the delivery of high-value mobile services.
In general, communication quality at high speed becomes unstable due to the influence of direct-path obstructions and the Doppler effect. This is especially true in the case of 5G, which uses relatively high frequency bands that are more sensitive to physical obstructions and the Doppler effect compared to lower frequency bands used in legacy mobile communication networks.
Specifically, the trials confirmed the following three results aboard ALFA-X running at 360km/h:
Maximum data rates exceeding 500Mbps and 100Mbps in the downlink and uplink, respectively, were verified and highly stable communication at 100Mbps or higher was achieved over a distance of approximately 5km, confirming the possibility of practical, reliable communication.
Successful handover was confirmed while maintaining data rates at 100Mbps or higher.
Both 4K and 8K high-definition video data transmissions were achieved, confirming the possibility of stable, large-capacity data transmissions.
