Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Improvements in SIM Time Network and SIM Time Scale Performance



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


We report recent results achieved within the Sistema Interamericano de Metrología (SIM) regarding the multinational cooperation program in the field of time and frequency metrology. We discuss the performance of the SIM Time Network (SIMTN) and the SIM Time Scale (SIMT). We emphasize results achieved during the time period from May 2013 to May 2014. We found a significant improvement in both accuracy and stability of the SIMT approaching those of the UTCr of the Bureau International des Poides et Mesures (BIPM).
Proceedings Title
Proceedings of CENAM Metrology Symposium
Conference Dates
October 6-10, 2014
Conference Location
Conference Title
CENAM Metrology Symposium


disciplined oscillator, time, time scale, time transfer


Lombardi, M. , , J. , Diaz-Munoz, N. , , E. , Gertsvolf, M. and de, R. (2014), Improvements in SIM Time Network and SIM Time Scale Performance, Proceedings of CENAM Metrology Symposium, Queretaro, -1, [online], (Accessed April 18, 2024)
Created October 10, 2014, Updated February 19, 2017