Communication scheduling method for wireless relay systems

A communication scheduling method for a packet switched wireless multihop system including a wireless base station, a wireless relay station, and a plurality of subscriber stations for allowing the wireless base station and each subscriber station to perform packet switching via at least one relay station, in which same frequency channel is used at each communication direction;

• at downlink direction from the wireless base station to the wireless relay station and to the subscriber stations, and from the wireless relay station to the subscriber stations, and at uplink direction from the wireless relay station and from the subscriber stations to the wireless base station, and from the subscriber stations to the wireless relay station, the communication scheduling method comprising:
• a step of allowing the wireless base station to detect an interference downlink from the wireless base station to the wireless relay station and to the subscriber stations, and from the wireless relay station to the subscriber stations;
• a step of allowing the wireless base station to detect an interference uplink from the wireless relay station and from the subscriber stations to the wireless base station and from the subscriber stations to the wireless relay station;
• a step of allowing the wireless base station to, based on the detected interference information, form a communication schedule, for communicating on the same frequency channel between the wireless base station and the wireless relay station, between the wireless relay station and the subscriber station and between the wireless base station and the subscriber station, in which a packet is scheduled to be transmitted or received at the same timing as those of other packets as long as predefined conditions, which include a condition that the packet differs in its destination from the other packets and a condition that the packet does not cause interference, are satisfied, and the packet is scheduled to be transmitted or received at the new timing if the packet does not achieve said predefined conditions;
• a step of transmitting a frame in which a MAP of the communication schedule for communicating on the same frequency channel has been registered from the wireless base station to the wireless relay station;
• a step of allowing the wireless relay station to receive the frame in which the communication schedule for communicating on the same frequency channel has been registered;
• and
• a step of transmitting the frame in which the MAP of the communication schedule for communicating on the same frequency channel has been registered from the wireless relay station to the subscriber station.