基于UWB的无线网络精密时钟同步设计  

Design of precise clock synchronization in wireless networks based on UWB

作　　者：瞿智 张慧晴 陈建云[1] Qu Zhi;Zhang Huiqing;Chen Jianyun(College of Intelligence Science and Technology,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]国防科技大学智能科学学院,长沙410073

出　　处：《国外电子测量技术》2023年第6期86-92,共7页Foreign Electronic Measurement Technology

基　　金：国家自然科学基金(62001491)项目资助。

摘　　要：针对无线集群网络对低代价精密时钟同步的需求,设计了基于恒温晶振(oven controlled crystal oscillator,OCXO)和超宽带(ultra wide band,UWB)的无线网络亚纳秒级时钟同步系统。系统能够测量与矫正UWB模块与OCXO模块之间的相位偏移,将UWB模块的时间基准精确地溯源到OCXO,降低了系统时钟相位的不确定性。同时,构建了低尺寸、重量、功耗和成本(size,weight,power and cost,SWaP-C)时钟的高阶模型,设计了动态双单向测量机制与基于Kalman滤波器的动态时频估计方法,从而减小了时钟频率偏差和漂移等动态特性对同步的影响,实现亚纳秒级的无线网络时钟同步。实验表明,系统时频同步方法收敛迅速,同步精度优于0.15 ns。Aiming at the demand for low-cost precision clock synchronization in wireless cluster networks,a subnanosecond clock synchronization system for wireless networks based on oven controlled crystal oscillator(OCXO)and ultra wide band(UWB)is designed.The system can measure and correct the phase offset between UWB module and OCXO module,and it can accurately trace the time reference of UWB module to OCXO module,reducing the uncertainty of system clock phase.Meanwhile,a high order model of the clock with low size,weight,power and cost(SWaP-C)is constructed,and a dynamic dual one-way measurement mechanism and a dynamic time-frequency estimation method based on Kalman filter are designed,to reduce the impact of dynamic clock characteristics such as frequency deviation and drift on synchronization,and to achieve sub-nanosecond clock synchronization in wireless networks.Experiments show that the system time-frequency synchronization method converges quickly and the synchronization precision is better than 0.15 ns.

关 键 词：精密时钟同步 UWB 高阶时钟模型 动态时频估计 

分 类 号：TN98[电子电信—信息与通信工程]