Wireless communication systems can sometimes find it tough to maintain stable connections, especially when it comes to mobile terminals in cars, trains, and drones moving at high speeds. What often happens is that non-mobile systems, such as wireless LANs, suffer from degraded performance and connection drops at the edges of their coverage areas. This problem limits their use in dynamic, fast-moving environments.

NTT is looking for solutions to this issue. The company has developed a seamless switching technology that enables uninterrupted communication by detecting when a terminal is approaching the boundary of a non-mobile wireless system's coverage area. Using distance estimation via radio waves, the system preemptively switches to a mobile wireless communication system—such as 5G or LTE—before the connection drops. The solution has already been successfully tested in ultra-high-speed environments using formula cars, and offers the potential to make mobile communication much more flexible and reliable.

How has NTT done it? It's all about the technology's ability to estimate communication range accurately, using high-frequency band radio waves. By measuring the round-trip time of beam control information, the system works out the terminal's distance from the base station without having to rely on GPS or other positioning systems. When the terminal approaches the limit of the non-mobile system's range, it automatically and seamlessly switches to the mobile system, maintaining a stable connection.

During a recent demonstration at the 2024 All Japan Super Formula Championship, NTT fitted out a formula car with both WiGig (a 60 GHz band wireless LAN) and 5G/LTE communication systems. The car, traveling at speeds up to 278 km/h, was able to maintain uninterrupted communication by switching systems as it neared the edge of the WiGig coverage area. The test confirmed the technology's effectiveness in preventing communication drops, even when traveling at very high speeds.

It's a technology that you can imagine would have a wide range of possible uses. Here are just four ideas:

1. High-Speed Train Communication: Implementing seamless switching technology in high-speed trains to maintain uninterrupted internet connectivity for passengers. Passengers can experience high-speed internet without disruptions, enhancing onboard entertainment, real-time work capabilities, and improved communication services.

2. Autonomous Vehicles Data Transmission: Autonomous vehicles equipped with seamless switching technology can transmit large volumes of data (such as video from cameras, LiDAR data) to ground stations while in motion. NTT's tech enables real-time monitoring, decision-making, and data analysis for better navigation and safety, ensuring continuous communication despite high-speed travel.

3. Drone Operations: Drones used for delivery or surveillance can take advantage of the technology to maintain stable communication links while transitioning between different network zones. Drones are able to send high-resolution video feeds and other sensor data without interruptions, improving the reliability and effectiveness of operations over large areas.

4. Mobile Broadcasting: Broadcast units in mobile news vans or event coverage vehicles can use seamless switching to transmit live video feeds while moving between different wireless network zones. Imagine continuous, high-quality live streaming of events, reducing the risk of signal loss and ensuring consistent broadcast quality—even in high-speed environments.

The success of NTT's testing shows that non-mobile wireless communication systems can be integrated into mobile environments, which has the potential to greatly boost wireless communication capacity. And it's not just limited to WiGig, but can extend to other high-frequency band systems, making it a versatile solution for future wireless communication needs.

As we move into the IOWN/6G era, NTT's switching tech offers the prospect of optimizing non-mobile wireless systems in mobile terminals, providing stable and high-capacity wireless transmission. Improving wireless communication's stability and capacity in the fast-evolving digital landscape.

For further information, please see this link:
https://group.ntt/en/newsrelease/2024/04/26/240426a.html

If you have any questions on the content of this article, please contact:
NTT Information Network Laboratory Group
Public Relations
nttrd-pr@ml.ntt.com

NTT—Innovating the Future of Communication

Daniel O'Connor

Daniel O'Connor joined the NTT Group in 1999 when he began work as the Public Relations Manager of NTT Europe. While in London, he liaised with the local press, created the company's intranet site, wrote technical copy for industry magazines and managed exhibition stands from initial design to finished displays.

Later seconded to the headquarters of NTT Communications in Tokyo, he contributed to the company's first-ever winning of global telecoms awards and the digitalisation of internal company information exchange.

Since 2015 Daniel has created content for the Group's Global Leadership Institute, the One NTT Network and is currently working with NTT R&D teams to grow public understanding of the cutting-edge research undertaken by the NTT Group.