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Uncertainty analysis for ac-dc difference measurements with the AC Josephson Voltage Standard



Jason M. Underwood


A detailed analysis of the uncertainties encountered in ac-dc difference measurements with an AC Josephson Voltage Standard (ACJVS) is presented. While the discussion is focused primarily on ac-dc difference, the results may be applied to other ac voltage metrology scenarios. For audio frequencies and for voltages less than 200 mV, ac-dc transfers with the ACJVS reduce the combined uncertainty by factors of 2 to 5, compared with conventional methods based on thermal converters. Type A uncertainties are predominantly limited by the unit under test (UUT), or the digital voltmeter used to readout the voltage from the UUT. The ACJVS transmission line is the primary contributor to Type B errors for frequencies above 10 kHz. A Monte Carlo sensitivity analysis is used to demonstrate how the uncertainties of transmission line impedance and on-chip inductance impact the accuracy of the rms amplitude conveyed to the UUT.


quantum voltage standards, ac-dc difference, uncertainty analysis


Underwood, J. (2018), Uncertainty analysis for ac-dc difference measurements with the AC Josephson Voltage Standard, Metrologia, [online], (Accessed July 13, 2024)


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Created December 21, 2018, Updated February 13, 2020