基于IEEE 1588的无线传感器网络时钟同步方法

Clock synchronous method for wireless sensor networks based on IEEE 1588

时钟同步是无线传感器网络的一项重要支撑技术,网络节点间的协作感知、数据融合、定位技术、能量管理都需要时钟同步的支持,才能正常开展。通过对影响802.11无线网络中IEEE 1588时钟同步精度的双向不对称时延的产生机理及统计特性进行详细分析,提出了一种基于卡尔曼滤波的时延过滤算法,并在此基础上设计实现了时钟伺服系统,从而实现了基于IEEE 1588协议的一种纯软件形式的无线传感器网络时钟同步方法。最后,通过实测验证了该方法的有效性。实测结果表明,该方法在同步精度、同步时间及偏移误差上达到了较高的指标。

Clock synchronization is an important supportive technology for wireless sensor networks （WSN）. Cooperative sensing among network nodes, data fusion, positioning technology and energy manage ment require clock synchronization support to carry out. A delay filtering algorithm based on Kalman filter is de signed by conducting a detailed analysis of the generation mechanism and the statistical properties of 802. 11 wireless network bidirectional asymmetric delays which affect the IEEE 1588 clock synchronous accaracy. And a clock servo system is designed based on the delay filtering algorithm. A pure software clock synchronous method based on IEEE 1588 for wireless sensor networks is established. Finally, the effectiveness of the method is verified. The results show that the synchronous precision, synchronous time and offset error achieve a high performance.