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Measurements >> Phase Noise and Jitter Measurements >> Phase Noise through the NTF of VCO
https://designers-guide.org/forum/YaBB.pl?num=1634826957

Message started by subtr on Oct 21^st, 2021, 7:35am

Title: Phase Noise through the NTF of VCO
Post by subtr on Oct 21^st, 2021, 7:35am

Assuming that I have a PSD of random noise on Vcontrol of VCO as discrete points from the simulator, eg. 50 points per decade. Now I have to simply find the phase noise at the output of the VCO. Do I :
A. assume the NTF is Kvco/f, do dot product of PSD and square(Kvco/f) at the corresponding frequency points?
OR
B. Now that the points are discrete, I assume each bin value is a sinusoid, convert the rms to peak by sqrt(2) and then get the USB/LSB as half the value and then dot product by square(Kvco/f) at the corresponding frequency points?

A and B differ by a scaling factor due to the sinusoid assumption.

Title: Re: Phase Noise through the NTF of VCO
Post by smlogan on Jan 17^th, 2023, 9:19am

Dear subtr,
Do you still have an interest in your question? If so, I can share an Excel workbook that you can use to place your control voltage noise data (noise versus frequency) and it will plot the resulting output phase noise given the Kvco.

Shawn