Performance Investigation of IEEE 802.11e EDCA Based on the M/G/1/K Queue Model
基于M/G/1/K排队模型的IEEE802.11e EDCA性能研究

A new Markov chain model for the IEEE 802.11e EDCA is presented. The model takes into account both the idle state and differentiation based on different AIFS-value for different traffic. The signal transfer function of the generalized state transition diagram can be used to derive a probability distribution of the MAC layer service time and the performance of EDCA from a non-saturated channel to a saturated medium by using presented M/G/1/K queuing model is analyzed. A good match between the analytical model and simulation which conforms the veracity of proposed model is observed. Simulation shows that despite providing prioritized QoS, the EDCA still can not support strict QoS for real-time application. It is inevitable that there is unfairness of channel access to prioritized traffic due to EDCA.