一种提高能量效率的Ad Hoc网络MAC层协议  

A MAC Protocol for Improving Energy Efficiency of Ad Hoc Networks

作　　者：余旭涛[1] 张在琛[2] 毕光国[2] 

机构地区：[1]东南大学毫米波国家重点实验室,南京210096 [2]东南大学移动通信国家重点实验室,南京210096

出　　处：《计算机学报》2006年第2期256-266,共11页Chinese Journal of Computers

基　　金：国家"八六三"高技术研究发展计划项目基金(2005AA123320);江苏省自然科学基金(BK2005409)资助~~

摘　　要：能量问题是Ad hoc网络中一个非常重要的问题,文中提出了一种基于节点休眠模式的媒体接入控制协议———PEMAC链路协议.采用PEMAC协议,节点处于空闲状态一段时间后如果没有数据发送或者节点收到目的地址为其它节点的RTS/CTS消息后将进入休眠状态,从而节省了能量.论文对PEMAC协议进行了建模分析,给出了该协议的离散Markov链模型,并通过该模型求得在一定参数条件下的节点最佳休眠时间的公式.分析和仿真结果表明,采用该协议可以有效地延长网络生存时间.Ad hoc networks are multi-hop wireless networks without fixed infrastructure. Because node＇s strong dependency on batteries, the Ad hoc networks are energy constrained. How to improve energy efficiency is an important design issue due to the limited battery life. In this paper, in the MAC layer, a new energy efficiency MAC protocol called PEMAC is proposed. High energy efficiency can be achieved by switching a node into a sleeping state when the node is not transmitting or receiving, in the sleeping state, energy consumption is very small compared with those in usual transmitting, receiving, or idle states. A power saving protocol solves the problem of when to make a node sleep and when to awake it in a network, so that energy consumption is minimized and network throughput is maximized. This protocol reduces the energy consumption of network interface. Using PEMAC, a node with packet to transmit sends a RTS message, and the destination node returns a CTS. The node should switch into the sleep state if there is no packet to transmit after an idle period or it receives an RTS/CTS message destined to other node. A Markov chain model for PEMAC is presented to get the optimal sleeping time of the node. Simulation results show that compared with conditional IEEE 802.11 Ad hoc networks, PEMAC outperforms in terms of network lifetime and network throughput.

关 键 词：AD HOC网络 能量 媒体接入控制 休眠 MARKOV链模型 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]