• 中国计算机学会会刊
  • 中国科技核心期刊
  • 中文核心期刊

J4 ›› 2012, Vol. 34 ›› Issue (12): 39-44.

• 论文 • 上一篇    下一篇

IEEE 802.11无线局域网二进制指数退避算法改进与分析

彭静1,朱艺华2   

  1. (1.浙江农林大学信息工程学院,浙江 临安 311300;
    2.浙江工业大学计算机科学与技术学院, 浙江 杭州 310023)
  • 收稿日期:2011-12-02 修回日期:2012-02-23 出版日期:2012-12-25 发布日期:2012-12-25
  • 基金资助:

    国家自然科学基金资助项目(61070190);浙江省自然科学基金资助项目(Y1090781);浙江省教育厅项目(2271000024);浙江林学院科研发展基金资助项目(2351000583)

Improvement and Analysis of Binary Exponential Backoff Algorithm for IEEE 802.11 Based Wireless Area Networks

PENG Jing1,ZHU Yihua2   

  1. (1.School of Information Engineering,Zhejiang Agriculture and Forestry University,Lin’an 311300;
    2.School of Computer Science and Technology,Zhejiang University of Technology,Hangzhou 310023,China)
  • Received:2011-12-02 Revised:2012-02-23 Online:2012-12-25 Published:2012-12-25

摘要:

IEEE 802.11标准引入二进制指数退避算法BEB,以降低节点发送数据包碰撞的概率。两步指数退避算法TBEB避免了BEB算法中竞争窗口长度出现振荡这一现象,可以提高吞吐率。导出了TBEB算法和BEB算法中节点的平均竞争窗口长度和平均退避次数的解析表达式,并采用仿真进行验证;以退避时间最小为目标,给出了求解竞争窗口长度最优复位值的优化模型。研究结果可用于基于IEEE 802.11无线局域网的BEB算法的性能评价。

关键词: IEEE 802.11标准, 无线网络, 竞争窗口, 二进制指数退避算法

Abstract:

Binary Exponential Backoff (BEB) algorithm is introduced in the IEEE 802.11 standard in order to reduce probability of packet collision.Twostep BEB (TBEB) algorithm overcomes the oscillation in contention window size arising from the BEB so that the throughput is improved.The closedform expressions of the TBEB and the BEB are derived and then validated by simulation.In addition, an optimization problem that minimizes the backoff time is presented to find the best size for resetting contention window.The proposed outcomes are applicable in evaluating the performance of the BEB.

Key words: IEEE 802.11 standard;wireless network;contention window;binary exponential backoff algorithm