Actual proof of control technology for switching base stations using positioning information derived from communication radio waves for the first time in the world

-Realizing wireless broad band transmission in the 60 GHz band to a formula car running at 300 km/h -

Nippon Telegraph and Telephone Corporation (NTT, Head office: Chiyoda-ku, Tokyo, President & CEO: Jun Sawada) has invented the control technology that allows base stations to be switched using positioning information derived from communication radio waves, and demonstrated broad band transmission in the 60 GHz band to a formula car running at 300 km/h for the first time in the world*1. The demonstration experiment was held at Fuji Speedway from December 22nd (Tuesday) to 23rd(Wednesday), 2020 at the "Joint Test / Rookie Test of the All Japan Super Formula Championship", with the cooperation of the racing team "DOCOMO TEAM DANDELION RACING", NTT DOCOMO, Inc. (hereinafter "DOCOMO") and DOCOMO Technology, Inc. (hereinafter "DOCOMO Technology"). The control technology concept is based on the function of WiGig*2, which has the ability to acquire positioning information of terminal direction and distance from the base station from communication radio waves. Demonstrations were conducted in which base stations instructed the terminal to switch its base station connection at the appropriate timing based on the positioning information (Fig, 1). The experiment showed that stable and successful switching of the connecting base station was possible within 500 [msec] while the terminal station was traveling at 300 km/h (at speed measurement point*3) while keeping the uplink throughput of 1 [Gbit/s] or more. This is the world's first proof*1 of control technology for switching base stations based on the positioning information derived from communication radio waves while realizing large-capacity wireless transmission in an actual high-speed mobile environment. This experiment shows the possibility of implementing large-capacity wireless transmission such as high-definition video data to high-speed mobile objects such as cars and drones even if the wireless transmission system does not have a soft handover function *4 such as WiGig. In addition, the technology verified in this experiment has the potential to be support the fusion of sensing and control functionalities in the millimeter-wave and terahertz wave bands for Beyond 5G.

Fig.1 Formula car used in the experiment

• 1. As of February 2, 2021, NTT examined
• 2. Abbreviation for Wireless Gigabit. Wireless LAN standard using 60 GHz band based on IEEE 802.11ad standard
• 3. A point for measuring the speed of Formula cars in front of the first corner on the main straight. 200 m from the WiGig base station at the experiment site
• 4. Technology that allows terminal stations to connect to multiple base stations at the same time and switch base stations without interruption