第21卷第12期
2013年12月文章编号
1004-924X(2013)12-3231-08
光学精密工程
Optics and Precision Engineering
Vol.21No.12
Dec.2013
无线传感器网络跨层服务优化时间同步机制
陈桂芬，王义君*
（长春理工大学电子信息工程学院，吉林长春130022）
摘要：针对无线传感器网络时间同步技术对采集时间数据依赖性强的问题，提出一种跨层服务优化时间同步机制。该技术首先对无线传感器网络链路层MAC层协议顿报头进行有效分片，利用区域划分技术重新定义网络覆盖范围。然后，对MAC层超慎结构进行调整，通过时隙退避算法解决网络中存在的隐藏节点间题。在完成MAC层优化后，在网内区域节点发送广播消息顿结构中加人时间截，通过时间截记录接收消息时间数据。最后，通过聚类技术对所有接收误差数据进行过滤，得到时间同步有效数据，进而补偿同步时钟漂移。仿真结果显示，在不同网络规模下与传统同步方案相比，该机制同步精度提高了8μS，收效时间降低了10%，能量消耗不到150mW。上述结果表明，该技术在保证时闻同步精度的同时，缩短了同步收敛时间，降低了网络能量消耗。
关键调：无线传感器网络；时间同步；跨层服务；MAC层
中图分类号：TN92
文献标识码：A
doi:10.3788/OPE.20132112.3231
Optimizationtimesynchronizationincross-layerserviceforWsNs
CHEN Gui-fenWANG Yi-jun'
(School of Electronic&InformationEngineering,Changchun Uniuersity of
Scienceand Technology，Changchun130022，China)*Correspondingauthor,E-mail:wyjs-107@163.com
Abstract: The current time synchronization algorithms for Wireless Sensor Networks(WSNs) are de pendent on the collected time data strongly. Therefore, an optimization time synchronization technol-ogy for cross-layer service was presented to work out related issues. Firstly, frame header fragmenta-tion in a MAC layer was used for the fragment and reassembly of packets. By zoning techniques,su perframe structure of the MAC layer was adjusted, and then the hidden node problem was solved through the slot backoff algorithm. Then, a timestamp was added into the frame structure of the broadcast message to record the time data of received messages, and all received error data were fil-tered through clustering techniques. Also the synchronous clock drift was compensated. The simula-tion results indicate that the time synchronization accuracy is improved by 8 μs, the convergence time is reduced by 10% and the energy consumption is less than 150 mW compared with those of other tra ditional algorithms, These results prove that the technology ensures the accuracy, and simultaneously reduces the convergence time and the energy consumption of the network.
Key words: Wireless Sensor Networks(WSN);time synchronization; cross-lay service; MAC layer
收稿日期：2013-10-12；修订日期：2013-10-30.
基金项目：国家863高技术研究发展计划资助项目（No.2008AA7010214）