Patent ID: 6934554

Claim:
A radio communication system comprising a plurality of radio stations, wherein each said radio station manages at least one radio channel for packet radio communication, wherein each said radio station communicates with another radio station either directly or through at least one other radio station, wherein each said radio station communicates with an adjacent radio station in one of centralized control access phase and distributed control access phase for each radio channel, whereby, in the centralized control access phase, each radio station operates adaptively either as a master station which controls transmission right and transmits a signal according to control of the own radio station or as a slave station which transmits a signal under control of a master station, for each channel, wherein said centralized control access phase and said distributed control access phase are switched on time divisional basis for each radio station and for each radio channel, wherein when a radio station operates in a radio channel as a master station, said radio station transmits a beacon packet including an address of said master station, an address of all the slave stations belonging to said master station and time until each slave station should transmit a request packet to said master station response to said beacon packet, for indicating beginning of a centralized control access phase, and each slave station, upon receipt of said beacon packet, transmits said request packet to said master station at a time instructed by said beacon packet, and wherein a pair of radio stations operating under relation of a master station and a slave station finish the centralized control access phase and switch to the distributed control access phase, said master station transmits a contention free end packet indicating an end of the centralized control access phase, said contention free end packet includes an end time of said centralized control access phase, a time until a next beacon packet is transmitted, and an instruction whether or not a slave station receiving said contention free end packet should relay said contention free end packet to another slave station, and a slave station which receives said contention free end packet transmits the other contention free end packet to said master station at a time indicated by said contention free end packet sent by the aster station, so that the centralized control access phase switches to the distributed control access phase.