移动自组网多速率MAC协议吞吐量分析及优化  

Throughput analysis and optimization of MAC protocol with multiple rates in mobile Ad Hoc network

作　　者：朱清超[1] 陈靖[1] 龚水清[1] 

机构地区：[1]空军工程大学信息与导航学院,西安710077

出　　处：《计算机应用》2016年第10期2664-2669,共6页journal of Computer Applications

摘　　要：针对移动自组网（MANET）多速率媒体接入控制（MAC）协议吞吐量和公平性偏低问题,推导不同发送速率节点吞吐量表达式,定量分析限制协议性能的关键在于低速率节点和高速率节点信道占用时间的不公平性。基于时间公平性最大化考量,在不影响低速率节点性能的前提下,提出低速率节点竞争窗口和分组长度最优化两种机制,最大化高速率节点吞吐量,使网络饱和吞吐量最优。实验结果表明,发送速率为1 Mb/s和11 Mb/s且Jain公平索引值最大时,低速竞争窗口仿真和理论最优值为320和340,分组长度为64 B和60 B,且低速节点吞吐量基本不变,但饱和吞吐量理论值比仿真时高0.2~0.5 Mb/s,公平性和吞吐量均得到改善。Concerning the low throughput and fairness of multi-rate Medium Access Control （MAC） protocol in Mobile Ad Hoc Network （MANET）, saturation throughput expressions of nodes with different rates were deduced, and the key factor to restrict performance of MAC protocol was quantitatively analyzed, which is unfairness of channel occupancy time between Slow rate Nodes （SN） and Fast rate Nodes （FN）. Secondly, focusing on maximizing time fairness among different rates of nodes, two optimal methods of Contention Window （CW） and packet size were presented without affecting the throughput of SN but maximizing the throughput of FN, which makes the saturation throughput of MANET optimal. Experimental results show that, to maximize Jain fairness index when packet rates of two types of nodes are set to 1 Mb/s and 11 Mb/s, optimal values of CW in simulation and analysis are 320 and 350, respectively; similarly, values of packet size are 64 B and 60 B. Moreover, although saturation throughput value of SN basically remains unchanged, the total throughput of analysis is still 0.2-0.5 Mb/s higher than that of simulation. Therefore, throughput and fairness are both improved.

关 键 词：移动自组网 时间公平性 饱和吞吐量 媒体接入控制 信道占用时间 

分 类 号：TP393.04[自动化与计算机技术—计算机应用技术]