Chaining Clock Synchronization: An Energy-Efficient Clock Synchronization Scheme for Wireless Sensor Networks

Since WSNs have restricted energy sources, the energy efficiency of a synchronization scheme is as important as the accuracy of a clock. To accomplish both the energy efficiency and the accuracy, we propose a new clock synchronization scheme called Chaining Clock Synchronization (CCS). In CCS, a subset of nodes whose transmission range cover the overall network carries out a two-way message exchange algorithm while the remaining nodes synchronize themselves by overhearing the messages. To reduce the energy consumption associated with the message exchange, CCS integrates a clock request and a clock reply into a single message. Therefore, CCS requires only a single message transmission per node for the synchronization. To increase the accuracy of the clock synchronization, we also propose a new technique called clock skew propagation to reduce the error accumulation associated with multi-hop clock synchronization schemes. According to the results from NS-2, in comparison with TPSN, CCS can effectively reduce the energy consumption by up to 95% while sacrificing 9.2% of the average accuracy of clocks. Moreover, the average clock error accumulation of CCS is reduced by 58% as the hop distance from a reference node increases.

[1]  Saurabh Ganeriwal,et al.  Timing-sync protocol for sensor networks , 2003, SenSys '03.

[2]  J. Elson,et al.  Fine-grained network time synchronization using reference broadcasts , 2002, OSDI '02.

[3]  Ajay K. Poddar,et al.  Voltage controlled crystal oscillator , 2009, 2009 IEEE Sarnoff Symposium.

[4]  David L. Mills,et al.  Internet time synchronization: the network time protocol , 1991, IEEE Trans. Commun..

[5]  F. Alagoz,et al.  Periodic Global Broadcast Time Synchronization (PGB-TS) for TDMA Based Sensor Networks , 2007, 2007 3rd International Conference on Recent Advances in Space Technologies.

[6]  Mihail L. Sichitiu,et al.  Simple, accurate time synchronization for wireless sensor networks , 2003, 2003 IEEE Wireless Communications and Networking, 2003. WCNC 2003..

[7]  Hui Zhou,et al.  Comparison among precision temperature compensated crystal oscillators , 2005, Proceedings of the 2005 IEEE International Frequency Control Symposium and Exposition, 2005..

[8]  Flaviu Cristian,et al.  Probabilistic clock synchronization , 1989, Distributed Computing.

[9]  Gyula Simon,et al.  The flooding time synchronization protocol , 2004, SenSys '04.

[10]  Erchin Serpedin,et al.  Pairwise Broadcast Clock Synchronization for Wireless Sensor Networks , 2007, 2007 IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks.

[11]  Yingyu Wan,et al.  Accurate Time Synchronization for Wireless Sensor Networks , 2005, MSN.

[12]  Panos M. Pardalos,et al.  On the Construction of Virtual Backbone for Ad Hoc Wireless Network , 2003 .