OAR速率自适应机制的改进与实现

Improvement and Realization of OAR rate adaptation algorithm

以最大化AdHoc网络吞吐量为目标,研究了基于IEEE802.11协议的物理层和MAC层信道接入机制和速率选择机制,分析了经典的速率自适应机制,但这些速率自适应机制绝大多数是针对数据帧提出的,而针对控制帧的速率自适应机制还非常少见。在研究基础上提出了一种控制帧速率自适应机制,详细阐述了实现过程,并对改进机制进行了仿真。仿真结果表明:通过控制帧速率自适应能有效地降低系统总开销,提高网络吞吐量。

To maximize network throughput,this paper makes research on channel access mechanism and the rate selection mechanism in MAC layer and physical layer of Ad hoc network based on IEEE 802.11 protocol,and introduces the classical rate adaptation mechanisms in detail：ARF,RBAR and OAR.Most of the rate adaptation algorithms are about the data frame rate.However,the rate adaptation algorithm about the control frames is still very rare.This paper proposes a new rate adaptation algorithm for the control frames and specifies its realization mechanism.The paper uses the network simulation tool ns2 to simulate the proposed rate adaptation algorithm The simulation results show that the proposed rate adaptation algorithm can effectively reduce overall system cost,increase the system throughput in different settings.