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Real-Time Generation of the SIM Time Scale (SIMT) from International Clock Comparisons

Published

Author(s)

Michael A. Lombardi, Jose M. Lopez, Andrew N. Novick, Francisco Jimenez, Nelida Diaz-Munoz, Eduardo de Carlos Lopez, Jean-Simon Boulanger, Raymond Pelletier, Ricardo de Carvalho, Raul Solis, Harold Sanchez, Liz C. Forero, Junior Gordon, Daniel Perez, Eduardo Bances, Leonardo Trigo, Victor Masi, Henry Postigo, Anthony Questelles, Anselm Gittens, Rodrigo Ramos P.

Abstract

The Sistema Interamericano de Metrologia (SIM) is one of the world’s five major regional metrology organizations (RMOs). The SIM members are the national metrology institutes (NMIs) located in the 34 nations of the Organization of American States (OAS). The SIM/OAS region extends throughout North, Central, South America and the Caribbean Islands. About half of the SIM NMIs maintain national standards of time and frequency and participate in international comparisons in order to establish metrological traceability to the International System (SI) of units. The SIM time network (SIMTN) was developed as a practical and cost effective way to automate the time comparisons between the SIM NMIs. The SIMTN continuously compares the time standards of SIM NMIs and produces measurement results in real-time by utilizing the Internet and the Global Positioning System (GPS). The SIMTN data are used for the near real-time generation of an international time scale called SIMT. This paper provides a brief overview of the SIMTN and the SIMT.
Proceedings Title
Proceedings of 2011 General Assembly and Scientific Symposium of International Union of Radio Science (URSI)
Conference Dates
August 13-20, 2011
Conference Location
Istanbul

Keywords

clock comparisons, GPS, Internet, time scales

Citation

Lombardi, M. , Lopez, J. , Novick, A. , Jimenez, F. , Diaz-Munoz, N. , de, E. , Boulanger, J. , Pelletier, R. , de, R. , Solis, R. , Sanchez, H. , Forero, L. , Gordon, J. , Perez, D. , Bances, E. , Trigo, L. , Masi, V. , Postigo, H. , Questelles, A. , Gittens, A. and Ramos, R. (2011), Real-Time Generation of the SIM Time Scale (SIMT) from International Clock Comparisons, Proceedings of 2011 General Assembly and Scientific Symposium of International Union of Radio Science (URSI), Istanbul , -1 (Accessed May 27, 2024)

Issues

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Created August 13, 2011, Updated February 19, 2017