网络时间同步的不确定度评定研究

为了评定网络时间同步的不确定度，基于中国计量科学研究院的网络时间服务系统，以时间综合测量仪 TimeAcc-007为时差测量仪器，在局域网环境下设计并进行网络时间同步实验。分析了客户端和服务器端同步实验测量的时差数据，建立了网络时间同步的时差不确定度数学模型，分析并评定了测量结果重复性、服务器参考 源、服务器时间戳、客户端时间戳及网络往返路径时延等不确定度分量。结合不确定度分析结果，提出了改善网络 授时精度的相关算法。

Research on the Uncertainty Evaluation of Network Time Synchronization

The LAN NTP experiments based on the network time service system ( NIM) are design and performed by a time and frequency solutions TimeAcc-007 in order to evaluate the uncertainty of network time synchronization. The time offset data of synchronization experiments are analyzed for clients and servers. The mathematical uncertainty model of NTP time offset is established. The uncertainty components, including repeatability of measurements results, reference source of server, server timestamp, client timestamp, round-trip delay of network, are analyzed and evaluated. The data processing algorithms are proposed for improving synchronization precision based on the results of uncertainty evaluation.