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A new algorithm for clock weights for the SIM time scale



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


A time and frequency comparison system has been developed for the Sistema Interamericano de Metrologia (SIM) region in order to compare in real time the time references maintained at the SIM national metrology institutes (NMIs). Since January 2010 a regional time scale (SIMT) is computed every hour and its values are disseminated in near real time by the Internet. The SIMT has proved to be a very helpful reference to monitor performance of the UTC(k) and SIMT(k) scales at the SIM region. In this paper we discuss the new algorithm for weights on the SIMT computation where an accuracy factor is introduced in order to limit the participation of SIMT(k) scales proportionally to the inverse of its frequency differences with respect to the SIMT.
Proceedings Title
2012 Proceedings Simposio de Metrología, Querétaro, México
Conference Dates
October 8-12, 2012
Conference Location


time, time scales, time transfer


Lombardi, M. , , J. , Diaz-Munoz, N. and , E. (2012), A new algorithm for clock weights for the SIM time scale, 2012 Proceedings Simposio de Metrología, Querétaro, México, Queretaro, -1 (Accessed April 22, 2024)
Created May 24, 2012, Updated February 19, 2017