Time Synchronization for Wireless Sensor Networks with a Mobile Node
Xiaoming Wu, Yinglong Wang, Fuqiang Wang, Peng Zeng, Yang Xiao and Wenlin Han
Time synchronization is a key technology for Wireless Sensor Networks (WSNs) and had been studied by many researchers. However, most of the proposed schemes employ hop-by-hop time synchronization and none of them can maintain the consistency of multi-hop error. In this paper, a mobile node is introduced to a fixed WSN, and the mobile node serves as the time source. Time information spreads across the whole network when the mobile node moves. The synchronization process does not depend on any special network topology. Because the synchronization information of the nodes in the network is directly derived from the mobile node, the time synchronization between nodes in the network keeps in good consistency. Experimental results show that our synchronization method greatly improves the stability and consistency of the time precision in compare with the traditional hop-by-hop synchronization methods.
Keywords: Wireless sensor networks, time synchronization, mobile node, consistency, scalability.