Communication among vehicles to avoid accidents

To support safe driving and avoid road accidents, we are conducting research and development of an inter-vehicle communication system which can achieve fast and reliable haring of position and speed information among vehicles.

Wireless communication with fast response and high reliability

When conventional wireless LAN technology is used for inter-vehicle communications, unacceptable delays and disruptions occur when large numbers of vehicles communicate simultaneously. In order to overcome this problem, we have developed a new wireless transmission scheme called Multi-carrier Multi-code Spread Aloha (MM-SA), which achieves fast-response and reliable transmission even when the number of vehicles is large.

Quick and Smooth Wireless Networking

Ad hoc networks and mesh networks realize flexible on-demand communications among wireless devices such as sensors, video cameras, video games and IP phones without the need for access to fixed and costly infrastructure such as cellular phone systems. We are developing technologies which offer fast, flexible, and reliable communications over such networks.

Avoiding congestion in wireless networks

The increase of communication traffic in a wireless network consisting of many devices causes severe congestion, which makes it difficult to achieve reliable communications. In order to overcome this problem, we have proposed packet forwarding techniques which adaptively avoid congested routes in wireless networks. We have also developed techniques which combine
packets to reduce congestion.

Efficient Use of Radio Spectrum

Methods for adaptive use of multiple wireless channels and systems according to actual radio conditions are being developed through our research on cognitive radio technology, for both more efficient use of radio-spectrum resources and enhanced performance of wireless terminals.

Providing reliable Internet access service

We are developing cognitive radio technologies which allow users to share wireless access to their home Internet connection, and combine this with access to public wireless networks. The collaborative use of home and public networks enables more reliable and high-speed Internet access service.