摘要
网络仿真器NS-2是目前无线网络仿真的重要工具之一,其主要采用门限判决法接收数据包,然而对于如何合理设置门限以保证数据包被正确高效接收,NS-2存在一定缺陷。根据NS-2数据接收原理,提出了一种新颖可靠的误帧率数学模型,并结合802.11b帧格式计算了IEEE 802.11b协议下的误帧率,给出了不同接收速率下的最佳数据包冲突门限采用误帧率模型进行仿真。仿真结果表明,合理门限值的设计有效提高数据接收的正确率以及NS-2的运行效率。
Network simulator （NS-2） is one of the important tool in wireless network simulation, which mainly u- ses Threshold Decision Method to receive packets. However, on how to set these reasonable thresholds to ensure that the packets are received correctly and efficiently, there are some flaws when running NS-2. In this paper, based on the analysis of the packet receiving process in NS-2, a novel and reliable mathematical model called Frame Error Rate Model （ FERM ） is proposed and FER is calculated with the frame format under the IEEES02. llb protocol. Different CPThreshes are recommended through mathematical results. Extensive simulations show that CSThresh should be equal to RxThresh. What＇ s more, these two parameters are decided with different receive sensitivity of the receiver. Different CPThresh should be set under the different velocity. Moreover,reasonable thresholds are designed to effectively improve the accuracy of the received data, as well as NS-2＂s operating efficiency.
出处
《计算机仿真》
CSCD
北大核心
2011年第1期151-154,237,共5页
Computer Simulation
