基于吞吐量比例公平的802.11MAC优化机制  

802.11 MAC Optimization Mechanism Based on Throughput Proportional Fairness

作　　者：巫素 严牧 冯钢[1] 

机构地区：[1]电子科技大学通信与抗干扰国家重点实验室,四川成都610054

出　　处：《无线电通信技术》2016年第1期12-17,共6页Radio Communications Technology

基　　金：国家高技术研究发展计划(863计划)(2014AA01A703)

摘　　要：802.11DCF MAC机制为单速率网络节点提供相同的信道接入机会,保证节点公平地使用信道。在多速率网络中依然沿用该接入机制,会导致低速率的节点长期占用信道,高速传输的优势得不到充分利用,使得多速率网络中所有节点的吞吐量都等于低速率节点的吞吐量,这就是著名的多速率网络"性能异常"问题。针对这一问题,通过分析建模,提出CCDa P(Change the CWmin according to Data rate and Packet-size)MAC优化机制以改善多速率网络中的节点的吞吐性能。仿真结果表明,该接入机制不仅可以保证节点公平性,还能提高网络整体吞吐量。特别地,在数据包长度不等的多速率WLAN中,该机制能够保证网络节点吞吐量的比例公平。The 802. 11 DCF MAC mechanism is initially designed for single rate networks. This mechanism provides every node with same channel access opportunities and ensures that every node fairly occupies channel. Currently the multi-rate networks still uses 802.11 DCF as the basic access mechanism,resulting in that low rate node persistently occupies channel,and thus cannot fully take advantages of high-speed transmission. The throughput of all the nodes in the network are driven down to the throughput of the low rate node,which is the widely known as ＂performance anomaly problem in multi-rate network＂. In view of this problem,this paper proposes a MAC optimization mechanism called CCDa P（ Change the CWmin according to Data rate and Packet-size） to ensure the node＇s throughput proportional fairness in multi-rate network based on analysis and modeling. The simulation results show that the proposed access mechanism can ensures all nodes throughput proportional fairness and improves the overall network throughput,particularly can ensure node＇s fairness in the multi-rate WLAN with unequal length of packet.

关 键 词：多速率WLAN IEEE 802.11 MAC 吞吐量 

分 类 号：TN915[电子电信—通信与信息系统]