工业物联网中的精确时钟同步:网络化控制理论观点

本文针对物联网中时变的时钟参数,运用网络化控制理论观点,通过对时钟状态建模的本质分析,区别于"相对时钟建模",提出了全分布规模化时钟状态追踪卡尔曼滤波(Kalman filtering).考虑量测的丢失,则扩展为追踪时钟参数的修正Kalman filtering 算法.我们提出了以 BMU(Basic measurem...

Precise Clock Synchronization in Industrial Internet of Things: Networked Control Perspective

In this paper, aiming at the time-varying clock parameters in the internet of things, the fully distributed scaled Kalman filtering for clock state tracking, which is different from the "relative clock modeling", has been proposed by using the point of view of the networked control theory through the essential analysis of the clock state modeling. Considering the loss of measurement, it can be extended to the modified Kalman filtering algorithm for tracking the clock parameters. We have proposed an observable state decoupling measurement model under a new MMSE (minimum mean square error) equivalent transformation based on BMU (basic measurement unit). The new measurement model is able to realize the scaled expansion of MMSE measurement, and theoretically analyze the conditions of clock synchronization and calculate the corresponding upper bound of statistical clock synchronization error, and quantify the balance between synchronization accuracy of clock and potential quality of the communication network.