Multi-phased carrier sense multiple access with collision resolution

Abstract

To improve the efficiency of carrier sense multiple access (CSMA)-based medium access control (MAC) protocol, CSMA with collision resolution (CSMA/CR) has been proposed. In the CSMA/CR protocol, a transmitting station can detect a collision by employing additional carrier sensing after the start of data transmission and resolve the next collision that might occur by broadcasting a jam signal during a collision detection (CD) period. By extending this original CSMA/CR protocol that uses a single CD phase, in this paper we propose a multi-phased CSMA/CR (MP-CSMA/CR) protocol that employs multiple CD phases. In the proposed MP-CSMA/CR protocol, colliding stations are filtered in each CD phase, and only surviving stations compete again in the next CD phase. Therefore, the collision resolution probability becomes higher as the CD phases proceed. Results show that the proposed MP-CSMA/CR protocol significantly outperforms the conventional CSMA/CR with a single CD phase.