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Time delay measurements: estimation of the error budget



G.D. Rovera, Marco Siccardi, Stefania Romisch, M. Abgrall


The measurement of the time difference between two heterogeneous electrical sources is a necessary task in several branches of metrology. In particular the dissemination of Coordinated Universal Time (UTC) around the world requires one to quantify the synchronization between two or more co-located time scales. The task is usually carried out using a time interval counter, by directly measuring the time difference between signals at its inputs. We found that special care must be taken when a total uncertainty significantly smaller than 1 ns is desired. The goal of this paper is to present a complete analysis of the total uncertainty for the measurement of time differences between co-located time scales, with considerations for improvement.


pulsed signals, time difference, uncertainty budget, rise time, jitter, time interval counter


Rovera, G. , Siccardi, M. , Romisch, S. and Abgrall, M. (2019), Time delay measurements: estimation of the error budget, Metrologia (Accessed June 25, 2024)


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Created May 16, 2019, Updated June 6, 2024