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Automated Control of National Time Standards via the SIM Time Scale

Published

Author(s)

Michael A. Lombardi, J. Mauricio Lopez-Romero, Nelida Diaz-Munoz

Abstract

This paper describes a frequency and time control system developed by the Sistema Interamericano de Metrologia (SIM). Due to limited resources, some SIM national metrology institutes maintain a low-cost rubidium clock as their national time standard, instead of the cesium clocks commonly found at larger laboratories. The system described here controls these clocks by adjusting them to agree with the SIM Time Scale (SIMT), which is distributed hourly via the Internet. The system has demonstrated the ability to keep time within {+or-}50 ns of SIMT, with frequency stability near 4 × 10-14 after one day of averaging. Due to the inherent stability limitations of the rubidium clocks, these performance levels would be impossible to maintain through manual adjustment.
Proceedings Title
Proceedings of 10th International Congress on Electrical Metrology, SEMETRO
Conference Dates
September 25-27, 2013
Conference Location
Buenos Aires
Conference Title
10th International Congress on Electrical Metrology, SEMETRO

Keywords

disciplined oscillator, frequency, GPS, time scale, time transfer

Citation

Lombardi, M. , , J. and Diaz-Munoz, N. (2013), Automated Control of National Time Standards via the SIM Time Scale, Proceedings of 10th International Congress on Electrical Metrology, SEMETRO, Buenos Aires, -1 (Accessed April 18, 2024)
Created September 27, 2013, Updated February 19, 2017