Research On Time Synchronization Algorithm Based On Large-scale Wireless Sensor Network

Wireless sensor network is widely used because of its large scale,strong flexibility and high cost performance.Time synchronization is one of the important supporting technologies of wireless sensor networks.Providing accurate time information is the premise to ensure the application of wireless sensor networks and the operation of its own protocol.After analyzing the characteristics of wireless sensor networks,this paper compares the performance of current time synchronization algorithms,and studies the time synchronization algorithm based on large-scale wireless sensor networks.Firstly,the research significance and progress of time synchronization algorithms for wireless sensor networks are introduced,and all kinds of time synchronization algorithms are analyzed and compared in detail.In the next part,through the analysis and comparison of various time synchronization algorithms,it is found that the distributed consistent time synchronization algorithm and flooding time synchronization algorithm had better performance in their respective application scenarios.The distributed consistent time synchronization algorithm has good scalability and high robustness,but it has slow convergence and high communication overhead.The flooding time synchronization algorithm has high synchronization accuracy,but it has the problem of multi hop synchronization cumulative error.Combining the characteristics of the two algorithms,a cluster based hybrid time synchronization algorithm(CHTS)is proposed by introducing the cluster topology.In CHTS algorithm,the distributed consistent time synchronization algorithm is used between clusters,and the flooding time synchronization algorithm is used within clusters.The combination of the two can effectively improve the performance of the time synchronization algorithm.Simulation results show that the hybrid time synchronization algorithm is more suitable for large-scale wireless sensor networks.Finally,in order to solve the problem of communication energy consumption caused by the frequent occurrence of emergencies and periodic broadcast synchronization parameters in large-scale WSNs,a time synchronization algorithm based on dynamic clustering is proposed.The new algorithm improves the clustering method and dynamically clusters according to the rapid response from emergencies.By this dynamic clustering method and consistent convergence based on the size of each cluster,the node time synchronization is realized quickly.Simulation results show that the new algorithm improves the convergence speed of the node synchronization in the burst region,and greatly reduces the network energy consumption.