有限负载下802.11 DCF的性能分析及优化  

Performance Analysis and Optimization for IEEE 802.11 DCF in Finite Load

作　　者：杨卫东[1] 马建峰[1] 裴庆祺[1] 

机构地区：[1]西安电子科技大学计算机网络与信息安全教育部重点实验室,陕西西安710071

出　　处：《电子学报》2008年第5期948-952,共5页Acta Electronica Sinica

基　　金：国家自然科学基金重点项目(No.60633020);国家自然科学基金面上项目(No.60503012;No.60573036)

摘　　要：利用三维马尔可夫链和M/G/1/K队列建立了有限负载下DCF机制的性能模型,分析了终端数量、传输负载、二进制指数回退机制及MAC层有限队列对系统性能的影响.基于该模型,推导了有限负载下最大化吞吐量的最优最小竞争窗口的闭式解.仿真结果表明,模型能够有效地预测有限负载下DCF的性能,根据传输负载调整最小竞争窗口大小能够获得最大化吞吐量.By using a three dimensional Markov chain and M/G/1/K queue,a performance model was proposed for IEEE 802.11 DCT in finite load, which analyzed the impact of different factors, including number of the terminals, traffic loads, the binary exponential back-off mechanism and the finite queue system at the MAC layer. Based on the model, the closed form of optimum minimum contention window maximizing the throughput under fmite load was derived. Simulation results show that the model can evaluate validly the performance of the DCF. By adjusting minimum contention window according to various traffic loads, maximized throughput can be obtained.

关 键 词：传输负载 分布式协调功能 吞吐量 分组时延 

分 类 号：TP391[自动化与计算机技术—计算机应用技术] TP334.4[自动化与计算机技术—计算机科学与技术]