The performance study of IEEE 802.11E EDCF in channel error environments

With the increasing variety of multimedia applications, it is needed to develop a mechanism for the quality of service (QoS) to support different types of traffic. IEEE 802.11e EDCF is a new wireless technology which is an enhanced version of DCF. There have been many performance studies of IEEE 802.11e EDCF and proposed an accurate Markov chain model to depict the IEEE 802.11e EDCF characteristics. However, the Markov chain model neglected the channel error condition. In other words, the Markov chain can not truly reflect the real operation of EDCF. In this paper, we modify the Ziouva and Antonakopoulous´s (ZA´s) model and then extend the model to support IEEE 802.11e EDCF. We study the behavior of the station within a Markov chain model. We have theoretically analyzed the saturation throughput of the Markov chain model with both the ACK and RTS/CTS CSMA/CA mechanisms under a channel error scenario. We also have compared it with the Markov chain model that exists under an ideal channel scenario.