基于延时限制的无线局域网DCF丢包率性能分析  

Packet dropping probability analysis of DCF based on delay constraint in WLAN

作　　者：程远[1] 张源[1] 高西奇[1] 

机构地区：[1]东南大学移动通信国家重点实验室,南京210096

出　　处：《东南大学学报（自然科学版）》2007年第5期751-755,共5页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(60572072;60496311);国家高技术研究发展计划(863计划)资助项目(2006AA01Z264);国家重点基础研究发展计划(973计划)资助项目(2007CB310603);国家博士点基金资助项目(20060286016)

摘　　要：针对无线局域网中具有延时限制的多媒体业务,提出了基于理想信道和有限数目节点假设的带延时约束的DCF接入丢包率分析模型.分析了基本接入方式下给定延时限制的系统丢包率性能并通过仿真验证了分析模型的可靠性.研究结果表明:在固定延时约束条件下,丢包率随系统中节点数量的增加而增大;在固定节点数目时,分组的延时限制越紧,丢包率越高.此外,还研究了初始竞争窗和最大退避阶数对丢包率性能的影响.Aiming at the multimedia services with delay constraint in IEEE 802. 11 WLAN （wireless local area networks）, a novel packet dropping probability analytical model is proposed under delay constraint of DCF （ distributed coordination function） based on the assumptions of ideal channel conditions and finite terminals. Packet dropping probability with delay constraint was analyzed for the basic access mechanism, and the accuracy of the proposed analytical model was verified by simulation. Study results show that, with a fixed delay constraint, the packet dropping probability boosts when the number of nodes increases. For a fixed number of nodes, the more rigid the delay constraint, the higher the packet dropping probability. Furthermore, the effect of initial contention window and maximum back-off stage on packet dropping probability is also investigated in the research.

关 键 词：DCF 延时限制 初始竞争窗 最大退避阶数 丢包率 

分 类 号：TN925[电子电信—通信与信息系统]