一种低开销的无线传感器网络时间同步算法

A Low Overhead Time Synchronization Algorithm for Wireless Sensor Networks

低开销是无线传感器网络时间同步算法的重要技术要求之一。为了降低同步过程中的通信开销,提出了一种基于部分广播的低开销无线传感器网络时间同步算法。算法基于TPSN算法的分层思想,利用节点的距离信息,选择当层节点的部分相邻节点进行下一层的等级广播,从而有效地降低同步过程中的通信开销。分析了在不同的网络节点密度下广播信息包数与等级广播距离的关系,得到了不同网络节点密度下的最优等级广播距离。仿真结果表明,与TPSN算法相比,在相同的同步精度下,算法能显著地降低高密度无线传感器网络时间同步的开销。

Low overhead is an important requirement of time synchronization algorithm of wireless sensor networks. In this paper, a low overhead time synchronization algorithm is proposed for reducing communication overhead in synchronizing. This algorithm, which is based on the level discovery mechanism used in TPSN, only selects fractional nodes in the broadcasting area of the current level node as the next level broadcast initiate nodes. As a result, the overhead of time synchronization is reduced effectively. The selection of next level broadcast initiate nodes is according to distance information of current level nodes. The relationship between number of broadcast packets and level - broadcast distance in different node density of networks is also analyzed. And the best level - broadcast distance in various node density of networks is given in the paper. Finally, simulation works validate that the algorithm greatly reduces the number of broadcasting packets for time synchronization in high density wireless sensor networks, while the synchronization precision is equivalent compared with TPSN.