The realization of Coordinated Universal Time, one of the tasks of the International Bureau of Weights and Measures, relies on a network of international time links which currently is organized in a star-like scheme that links all contributing laboratories. GPS signal reception is the technique most widely employed by the laboratories. The PTB currently plays a unique role in the process due to its function as the central pivot in the time transfer between the participating laboratories. We discuss how the PTB meets its obligations to the international timekeeping community as well as to its users in Germany. In its role as an National Metrology Institute (NMI), PTB is entrusted with the realization and dissemination of legal time in Germany. The services were offered to the public support measurements and timing applications traceable to the national and international standards to be made in calibration laboratories and in many industrial sectors. We thus discuss the meaning and definition of traceability, how different GNSS systems can be used to establish traceability and their performance in doing so.

中文翻译：

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通过GNSS接收器获得可追溯的时间和频率测量的可能性

协调世界时是国际度量衡局的任务之一，它的实现依赖于国际时间链接网络，该网络目前以星状方案组织，将所有贡献实验室连接在一起。GPS信号接收是实验室最广泛使用的技术。由于PTB作为参与实验室之间时间转移的中心枢纽，目前在该过程中扮演着独特的角色。我们讨论了PTB如何履行其对国际计时界及其在德国用户的义务。作为国家计量学院（NMI）的角色，PTB受托在德国实现和传播法定时间。这些服务是为可在校准实验室和许多工业领域进行的可追溯到国家和国际标准的公共支持测量和计时应用程序提供的。因此，我们讨论了可追溯性的含义和定义，如何使用不同的GNSS系统建立可追溯性及其在此过程中的性能。