摘要
时间同步是无线传感器网络的基本中间件之一.最近,许多基于时间信息交换的时间同步协议已被提出.然而,在大规模无线传感器网络中,同步误差随跳距的累积问题和可扩展性需求是传统的时间同步技术面临的主要挑战.为了应对这两个挑战,无线传感器网络的研究者们开始关注古老的萤火虫同步技术和最近才被提出的协作同步技术.直到最近,尤其是在Strogatz和Mirollo模型被提出以后,古老的萤火虫同步技术才在单跳网络内取得了突破性进展.而在多跳网络中,虽然已有大量的实验和仿真,但其收敛性仍有待从理论上进行研究.基于新颖的空间平均而非传统的时间平均的思想,协作同步技术为无线传感器网络时间同步提供了另外一个新的解决方案,尽管目前对其的研究仍停留于仿真阶段.介绍了萤火虫同步技术和协作同步技术的基本思想和目前在无线传感器网络中的研究及应用现状,并探讨了未来可能的研究方向.
Time synchronization is one of the basic middle-wares of wireless sensor networks. Many time synchronization protocols which are based on exchanging packets with timing information have been proposed in recent years. However, in large scale wireless sensor networks, the accumulation of synchronization error over hop distance and the demand for scalability challenge these traditional time synchronization techniques. To deal with these two challenges, researchers from the field of wireless sensor networks are beginning to pay. attention to the old technique of firefly-inspired synchrony and the new emerging cooperative synchronization technique. Great progress has been made in the technique of fireflyinspired synchrony in recent years, especially in single-hop network after the model of Strogatz and Mirollo was proposed. However, although a great number of experiments and simulations have been conducted, its characteristics of convergence in multi-hop network still needs to be found in theory. Based on the novel idea of spatial averaging instead of the traditional idea of time averaging, the technique of cooperative synchronization presents another new solution to time synchronization in wireless sensor networks although it is still strolling on simulation stage at present. Its basic idea and research and application status in wireless sensor networks are introduced. Future research directions are also proposed.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2008年第1期138-145,共8页
Journal of Computer Research and Development
基金
国家自然科学基金项目(90207002)
国家“八六三”高技术研究发展计划基金项目(2006AA01Z223,2006AA01Z225)
国家“九七三”重点基础研究发展规划基金项目(2005CB321604)~~
关键词
无线传感器网络
时间同步
萤火虫同步
协作同步
同步性
wireless sensor networks
time synchronization
firefly-inspired synchrony
cooperative synchronization
synchrony
