Abstract: Enhanced Distributed Channel Access(EDCA) of Wireless Local Area Network(WLAN) can support multi-class traffic. In order to reveal the essence of EDCA mechanism, a bi-dimensional Markov model is proposed to depict the EDCA scheme under finite load. The proposed model employs idle and post backoff states to deduce the channel throughput under both unsaturation case and saturation case, which also considers all characteristics of IEEE 802.11e EDCA, including the retransmissions, post-collision process. Simulation results show the accuracy of the proposed model. The results also reveal that the maximum throughput is achieved at the unsaturation case.

Key words: performance model, Enhanced Distributed Channel Access(EDCA), Wireless Local Area Network(WLAN)

摘要： 无线局域网增强的分布式信道接入(EDCA)具有支持多类型业务的功能。为准确有效地分析EDCA机制的性能，提出一个考虑多类型业务的受限负载二维马尔可夫性能分析模型。该模型通过引入空闲、后回退等状态来精确刻画饱和与非饱和负载下系统的性能，并考虑EDCA重传次数、后碰撞过程等特征。仿真结果验证了模型的有效性，系统的最大吞吐量出现在非饱和负载情况下。

关键词: 性能模型, 增强的分布式信道访问, 无线局域网

CLC Number: 

• TP393