METHOD AND SYSTEM FOR VEHICLE COMMUNICATION CONSIDERING COLLISION NUMNER

摘要

PURPOSE: A vehicle communication method considering the number of collisions and system thereof are provided to increase bandwidth and to reduce virtual collisions in MAC(multiple access categories). CONSTITUTION: An AC(access category) is determined according to a type of transmission traffic(S100). An AIFS(arbitration inter-frame space) and a CW(contention window) are set according to the determined AC(S110). When a generated collision is not an initial collision(S130), an ACW(adaptive contention window) is executed(S310). When an access channel is a CCH(control channel), the AIFS is decreased. When the access channel is an SCH(service channel), the AIFS is increased. [Reference numerals] (AA) Start; (S100) AC determination; (S110) AIFS/CW setup; (S120) Collision?; (S130) Initial collision?; (S140) AMCW & V-AIFS; (S160,S200) Is channel idle?; (S170) Back-off setup; (S180) AIFS waiting; (S190) Next packet generation?; (S200) Is channel idle?; (S210) Reducing back-off; (S220) Back-off>0?; (S230) SIFS waiting; (S240) Packet transmission; (S250) Transmission success?; (S260) Collision generation; (S270) Initial collision?; (S280) Next packet generation?; (S290) ACW; (S300) Increasing CW; (S310) ACW; (S320) Current packet disuse; (S330) AIFS/CW initialization; (S340) Increasing AIFS