IEEE 802.11无线局域网中基于最优窗口的退避算法  

Optimal Window Based Backoff Algorithm for IEEE 802.11 WLANs

作　　者：廖盛斌[1,2] 朱晓亮[1] 

机构地区：[1]华中师范大学国家数字化学习工程研究中心,武汉430079 [2]华中科技大学电信系,武汉430074

出　　处：《计算机科学》2012年第1期82-84,共3页Computer Science

基　　金：国家自然科学基金项目(60772088,61072051);武汉市科技攻关计划项目(201110821234);中央高校自主科研项目(120002040246)资助

摘　　要：首先通过把资源分配看成效用最大化的优化模型,说明在IEEE 802.11无线局域网中各个节点争用信道的退避窗口应当一样,然后通过最小化节点间的冲突概率,得出节点个数与最优退避窗口之间的关系,由此提出一种基于最优共享退避窗口的重传算法。由于各个节点的退避窗口一样,算法有效地解决了BEB(Binary Exponential Back-off)算法的不公平性问题;并且退避窗口根据网络的状况设置,吞吐量也得到了较大的提高。仿真试验验证了算法的有效性。That every node should have the same value of contention window（CW） was first vertisified in a WLAN by formulating resource allocation as a utility maximization optimal problem,then the relation between the optimal value of CWand the number of nodes was obtained by maximizing the total network utility with constrains of minimizing collision probability.A new retransmission algorithm was proposed which uses an optimal shared CW.Due to the same CW,the proposed algorithm can effectively overcome the unfairness of BEB algorithm and and improve throughput.Simulation results validate our conclusion.

关 键 词：效用 资源分配 最优化 退避算法 公平性 无线局域网 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]