  The aim of this paper is twofold. On one hand, it presents a
multi-dimensional Markovian state transition model characterizing the behavior
at the Medium Access Control (MAC) layer by including transmission states that
account for packet transmission failures due to errors caused by propagation
through the channel, along with a state characterizing the system when there
are no packets to be transmitted in the queue of a station (to model
non-saturated traffic conditions). On the other hand, it provides a throughput
analysis of the IEEE 802.11 protocol at the data link layer in both saturated
and non-saturated traffic conditions taking into account the impact of both
transmission channel and multirate transmission in Rayleigh fading environment.
Simulation results closely match the theoretical derivations confirming the
effectiveness of the proposed model.
