Cluster-based Time Synchronization Method For Wireless Sensor Networks

Wireless sensor network is composed of large amount of sensor nodes with the capabilities of data gathering, data fusion and wireless communication, which allow it to have a wide range of applications, high practicality and flexible to use. The research on wireless sensor network gets involved with many other subjects and the development of its key technology has aroused a huge surge of interest in which time synchronization is one of them. Traditional time synchronization techniques for Internet and Ad Hoc network cannot be applied to wireless sensor network for the reasons of communication capability, complexity and cost, which require better time synchronization method.The main work and achievement of this thesis are listed as follows:(1) The research in this thesis is focused on time synchronization in wireless sensor networks. Firstly, we introduce the structure, characteristic, application and challenges to be solved. Then, the necessity of time synchronization and its theory are presented, and on top of that, we give the reason why time synchronization protocol for traditional network can't be used here and demonstrate the shortcomings of existing algorithm.(2) A cluster-based time synchronization method is presented in this paper with special consideration of energy and topology of the network. Based on clustering of all nodes in-cluster loop was set up in which nodes perform on way synchronization together with receiver-receiver time synchronization to obtain energy-saving, robust and collaborative synchronization.(3) By comparing the simulation results we can see it meets the demands of synchronization precision and also can save energy communication overhead by 30-40%, which makes it a economical synchronization algorithm.Time synchronization involves other factors like data fusion and routing, so we have to conduct comprehensive experiment and it's effective on test-bed before applying to practical situation.