Fujitsu Corporation

Tohoku Electric Power Company, Inc.

Aomori Telemessage, Inc.

Hirokazu Murakami

Makoto Takahashi

Mamoru Machida

Toshihiro Yabe

Norio Sasaki

In a communication method, a wireless base station apparatus periodically sends a reference signal to a mobile station apparatus; the mobile station apparatus selects resources to be used for sending communication data to the wireless base station apparatus based on a receive time when receiving the reference signal first; the mobile station apparatus sends information on selected resources to the wireless base station apparatus, and sends communication data to the wireless base station apparatus using the selected resources; the wireless base station apparatus receives and demodulates the communication data based on the information on the resources sent from the mobile station apparatus.

Communication method, mobile station apparatus and wireless base station apparatus

When information of its own station is transmitted to another mobile station by a CSMA access method, by a transmission control method and device, moving speed information and location information is transmitted with a predetermined minimum transmission power until a moving speed of its own station exceeds a first threshold, and the moving speed information and the location information is transmitted with a first transmission power proportional to the moving speed when the moving speed of its own station exceeds the first threshold. In this case, moving direction information of its own station may be acquired and transmitted in addition to the moving speed information and the location information. If the moving speed of the other mobile station exceeds a second threshold higher than the first threshold and a moving direction of the other mobile station is an approaching direction to its own station while its own station is not making transmission with the moving speed of its own station exceeding the first threshold, the first transmission power is switched over to a second transmission power proportional to the moving speed of the other mobile station and the moving speed information and the moving direction information is transmitted.

Transmission control method and device

A radio calling system includes a central control station simultaneously broadcasting a calling signal of an arbitrary pager terminal, and a plurality of radio transmitting stations coupled to the central control station. The plurality of radio transmitting stations simultaneously transmit the calling signal received from the central control station at the same radio frequency. The calling signal transmitted from the radio transmitting stations reach the arbitrary pager terminal and at least a neighboring one of the radio transmitting stations. At least an arbitrary one of the radio transmitting stations includes a first relay for relaying the calling signal received from the central control station, a second relay which has a receiver part for receiving the calling signal transmitted from a radio transmitting station other than the arbitrary radio transmitting station, and a storage relay part for storing the calling signal received by the receiver part and for transmitting the stored calling signal during a time in which no transmission is made by the radio transmitting stations other than the arbitrary radio transmitting station. A switching circuit coupled to the first and second relays carries out switching to enable one of the first and second relays, depending on whether or not a communication failure exists between the central control station and the arbitrary radio transmitting station.

Growing community of inventors

Kawasaki, Japan

Hirokazu Murakami