Hi, I recently noticed something interesting: The DMTD measurement gives a set of phase values x(t). From which fractional frequency y(t) is calculable. So now it seems viable to plot the spectrum, Sy(f) and if you scale it properly you arrive at Sphi(f). If I'm not making a gross error somewhere the math seems to check out. But, I'm wondering is there a physical reason why this isn't valid?
I have not seen this being done anywhere - so I assume there is. However, it seems possible to plot Sphi(f) for 1Hz < f <100kHz when having a vbeat = 100kHz sampled for 1 second. I'm familiar with the loose and tight phase-locked methods of measuring phase noise, but am quite curious to know if phase noise from a DMTD measurement is a valid assumption. I would guess that if the frequency domain phase noise measurement requires phase-lock then the time-domain measurement requires as well. However, here in lies my real interest - two GPSDOs are phase-locked (not to 1Hz, something far less I know) so can it be possible to measure GPSDO Adev and phase-noise using a single DMTD run? Am I making a wrong assumption somewhere? Cheers, Stephan. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.