基于竞争的无线传感网络MAC协议研究
关键词 无线传感网 MAC协议 S-MAC 动态占空比
Title Research on Contention-based MAC Protocols
for Wireless Senor Networks
Abstract
Because of the broadcast nature of wireless channels, wireless signals
transmitted by one node in a wireless sensor network (WSN) would be received
by any other nodes within its communication range. Under the target of
minimizing energy consumption of nodes, how to effectively coordinate
multiple nodes so that they can share the wireless channel resources and
avoid collision is the main task of media access control (MAC) protocol
for WSN.
This paper focuses on the contention-based MAC protocol for WSN. The famous
S-MAC protocol is studied and analyzed. We find it cannot be adapt to
traffic changes due to its fixed duty cycle. Then we propose dynamic duty
cycle mechanism which enables each node to adaptively adjust listening time
in the same cycle time. The simulation results show that the S-MAC protocol
with dynamic duty cycle has the same energy efficiency performance as well
as better latency and throughput performance compared with original S-MAC
protocol.
Keywords wireless sensor networks MAC protocols S-MAC dynamic duty-cycle
目 次
1 绪论1
1.1 研究背景1
1.2 研究意义3
1.3 研究现状3
1.4 本文工作5
2 无线传感网MAC协议6
2.1 MAC协议设计准则 6
2.2 MAC协议分类 7
2.3 基于竞争的MAC协议8
3 S-MAC协议的分析与研究 .13
3.1 S-MAC 协议概述.13
3.2 S-MAC主要机制 .14
3.3 S-MAC存在的问题 .20
3.4 S-MAC九跳网络仿真 .23
4 一种改进的S-MAC协议.27
4.1 动态占空比机制的设计.27
4.2 动态占空比机制的改进.27
4.3 G-MAC两跳网络性能测试 .30
4.4 SMACJ、GMACJ、SMACNJ仿真 36
4.5 G-MAC四跳网络性能测试 .39
总结与展望.44
致 谢45
参 考 文 献46 1 绪论
1.1 研究背景
近几年来，随着微电子技术、计算技术和无线通信等技术的进步，使得信息
采集、数据处理和无线通信等多种功能，能在低成本、低功耗、多功能的微型传
感器内实现。无线传感网(wireless sensor networks，WSN)就是由部署在监测区域
内大量的廉价微型传感器节点组成， 通过无线通信方式形成的一个多跳的自组织
的网络系统， 其目的是协作地感知、 采集和处理网络覆盖区域中感知对象的信息，
并发送给观察者。传感器、感知对象和观察者构成了传感器网络的三个要素[1]。
无线传感网广泛应用于军事、工业、交通、环保等领域，被美国《技术评论》
杂志列为 21 世纪改变世界的十大新兴技术之首[2]。无线传感网技术涉及计算