Performance Analysis and QoE-Aware Enhancement for IEEE 802.11e EDCA under Unsaturations

In this paper, a novel non-saturation analytical model for enhanced distributed channel access (EDCA) in IEEE 802.11e wireless local area network (WLAN) is proposed. Unlike previous work focused on saturation conditions, this model uses Markov and M/M/1/K theories to predict MAC delay, service time, throughput and loss. Moreover, the EDCA technique resets the default contention window (CW) of stations statically after each successful transmission. The static behavior which can not adapt to the network state results in bad performance. Consequently, we introduce an enhancement scheme based on quality of experience (QoE) perceived by users to adjust CW adaptively. Instead of solely relying on technical parameters such as loss and delay, our scheme is based on QoE which contains the parameters inherently. Simulations validate this model and demonstrate better performance of our scheme compared with traditional EDCA regarding QoS parameters and user satisfaction.