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Optical Fiber Time Delay Comparison between NIST and LAMETRO



Tasshi Dennis, Johnny Jimenez


We describe the results of a bilateral measurement comparison of optical fiber time delay between the National Institute of Standards and Technology (NIST, USA) and Laboratorio de Metrología, Instituto Costarricense de Electricidad (LAMETRO-ICE, Costa Rica) on a singlemode optical fiber reference spool at wavelengths of 1310 nm and 1550 nm. The measurement results showed the largest difference to be less than 0.93 ns, which is within the combined standard uncertainty (k = 1) for the measurement systems at the two laboratories.
Journal of Research (NIST JRES) -


BIPM, international comparison, modulation phase shift, optical fiber, optical time domain reflectometer, OTDR, communications, time delay.


Dennis, T. and Jimenez, J. (2022), Optical Fiber Time Delay Comparison between NIST and LAMETRO, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 29, 2024)


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Created January 10, 2022, Updated November 29, 2022