APPARATUS AND METHOD FOR TRANSMITTING COEXISTANCE BEACON PROTOCOL PACKET IN A CONGNITIVE RADIO BROADBAND WIRELESS COMMUNICATION SYSTEM

摘要

PURPOSE: A CBP packet transmitting apparatus and method in a wireless communications system based on CR(Cognitive Radio) are provided to select a proper competitive target through the analysis of surrounding WRANs and increase the SCW life cycle in a WRAN which is defeated in competition, thereby setting a high reliable SCW rule pattern while preventing collision between CBP packets. CONSTITUTION: If entering a channel, a pattern analyzer(1132) analyzes the SCW(Self Coexistence Window) rule patterns of surrounding WRANs(Wireless Regional Area Networks). In case an unoccupied SCW slot is not periodically generated, a competition selector(1134) selects a WRAN having the shortest SCW life cycle as a competitive target. A backoff timer(1136) creates a random backoff time for competition with the competitive target at a start point of time of an SCW slot in which the competitive target transmits a CBP(Coexistence Beacon Protocol) packet. If the random backoff time is expired before the reception of the CBP packet of the competitive target, a RF(Radio Frequency) transmitter(1128) transmits the CBP packet.