Redundant Distributed Timescale Traceable to UTC(SP)
2019 (English)In: IFCS/EFTF 2019 - Joint Conference of the IEEE International Frequency Control Symposium and European Frequency and Time Forum, Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2019Conference paper, Published paper (Refereed)
Abstract [en]
A variety of commerce needs or requires accurate time, such as air traffic control, bank transactions and computer log file comparisons. Whenever the used time needs to be compared with a timestamp generated by another system, both systems must be traceable to a common reference, such as a local UTC(k) realization. Within this paper a distributed timescale using five nodes across Sweden is presented. The foundation for time keeping at each node is two cesium clocks, which are connected to time analysis equipment and equipment for producing redundant timescales. Both timescales are used and distributed throughout the time node and then prioritized by the local NTP servers, PTP grand masters, and other time distribution services. The timescales are monitored by RISE Research Institute of Sweden to ensure traceability to UTC(SP).To compare the timescales of each location with the other locations, GNSS common view is primarily used with an alternative fiber-based solution as back-up. All available time signals are measured relative to the master timescale, and that data is distributed to the other locations to be used as input in the steering of the local timescales. The NTP servers of the time nodes are directly connected to Internet Exchange points, for central, highly available and fair connectivity to the Internet.
Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc. , 2019.
Keywords [en]
holdover, redundant, robust, time dissemination, traceable, Location, Air traffic control
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-40616DOI: 10.1109/FCS.2019.8856058Scopus ID: 2-s2.0-85073793374ISBN: 9781538683057 (print)OAI: oai:DiVA.org:ri-40616DiVA, id: diva2:1372921
Conference
2019 Joint Conference of the IEEE International Frequency Control Symposium and European Frequency and Time Forum, IFCS/EFTF 2019, 14 April 2019 through 18 April 2019
Note
Funding text 1: The project was funded by the Swedish Post and Telecom Authority (PTS).
2019-11-252019-11-252023-06-08Bibliographically approved