Probability Process Analysis for Wireless LANs* with CSMA/CA Protocol

This paper presents an exact probability process analysis for high-speed and realizing fully distributed wireless LANs with non-persistent carrier sense multiple access with collision avoidance (CSMA/CA). The collision avoidance portion of CSMA/CA in this model is performed with a random pulse transmission procedure, in which a user with a packet ready to transmit initially sends some pulse signals with random intervals within a collision avoidance period before transmitting the packet to verify a clear channel. The system model consists of a finite number of users to efficiently share a common channel. The time axis is slotted, and a time frame has an arbitrary large number of slots and includes two parts: the collision avoidance period and the packet transmission period. A discrete-time Markov process is used to model the system operation. The influence of possible length of the collision avoidance period and packet transmission period, and pulse transmission probabilities on the network performance is discussed, based on the numerical results of the utilization of channel and average packet delay for the different packet generation rate, the length of collision avoidance period and pulse transmission probabilities.