Study On Low Energy Consumption Time Synchronization For Wireless Sensor Network

Wireless sensor networks integrated multiple technologies, such as sensor technology, distributed information processing technology, and embedded computing, wireless communication technology and so on, which provides a new way of collecting data. It let the information world and the physical world closely together, and changed the way of people interact the nature, improved the ability of understanding of the world. Accurate time synchronization is the basis of achieving its own agreement and TDMA scheduling, data fusion, and positioning technology. So time synchronization is a key technology and supporting technology of the wireless sensor network. Because characteristics of wireless sensor networks, the traditional time synchronization algorithm is not suitable for wireless sensor networks. Time synchronization is one of the focuses in research on wireless sensor networks.Energy is one of the greatest limitations for Wireless sensor networks. How to reduce consuming of energy that is important issues for wireless sensor network research and must be considered. Therefore, low energy consumption also is one of the important technical requirements of time synchronization algorithm of wireless sensor networks.This dissertation describes in detail the typical time synchronization algorithms, and analyzes their own characteristics. On this basis, Taking into the energy consumption in the level discovery phase that can not be neglected, and consumption of energy of pair-wise mechanism is too large. A greatly low energy consumption time synchronization algorithm for wireless sensor network is proposed, and is named LECTS. This algorithm, which is based on the base mechanism of TPSN algorithm,improve in two phases at the same time to reduce energy consumption. In the level discovery phase, using the distance between nodes limits part of nodes broadcast, to reduce the packets send. Meanwhile, in the synchronization phase, combining unidirectional reference broadcast and pair-wise mechanism, so that only one node in broadcast domain needs time synchronization, and also greatly reduces the messages. In this dissertation, first describes the algorithm in detail, and analysis the number of broadcast packets in the entire synchronization process, then verified by simulation, and compare with TPSN, STSP algorithm which is a improve algorithm on TPSN, about the number of broadcast data packets, energy consumption, synchronization accuracy. Analyze results show that the algorithm greatly reduces lots of broadcasting packets and exchange messages for time synchronization of wireless sensor networks, and node density the greater, the energy saving the more remarkable.