A Novel Method for Multitone Signal Characterization Using the AC Quantum Voltmeter

This article presents a new method for characterizing multi-tone signals measured with an AC quantum voltmeter. Using a four period signal from the programmable Josephson voltage standard, we overcome the previously missing short portions of the signal measured due to the transients. As an example, we show measurements and analyses of a two-tone signal with different fundamental frequencies and amplitudes. For these waveforms, we calculate the root mean square voltage and the harmonic content of the tones. The results obtained agree better than 1 μV/V with the expected values.