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Synchronizing Computer Clocks Using Kalman Filters



Judah Levine


I have used the Kalman Filter algorithm to improve the link between the Internet Time Servers operated by the National Institute of Standards and Technology (NIST) and the primary atomic clock ensemble in Boulder, which realizes UTC(NIST) and which is used as the reference for the time srevers. The Kalman algorithm is better able to separate the contribution of multiple noise sources such as the fluctuations in the asymmetry of the channel delay and the statistical fluctuations in the clock used as the internal reference for the time server. This improved separation has made it possible to compensate to some extent for the lower-quality telephone circuits that are often used as the links for synchronizing the time servers to the atomic clock ensemble.
Proceedings Title
Proceedings of 2011 Frequency Control Symposium
Conference Dates
May 1-4, 2011
Conference Location
San Francisco, CA
Conference Title
2011 Joint Conference of the IEEE International Frequency Control Symposium and European Frequency and Time Forum


automated computer time service, internet time service, Kalman Filter


Levine, J. (2011), Synchronizing Computer Clocks Using Kalman Filters, Proceedings of 2011 Frequency Control Symposium, San Francisco, CA (Accessed February 24, 2024)
Created July 31, 2011, Updated February 19, 2017