The Designer's Guide Community Forum

The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Measurements >> Phase Noise and Jitter Measurements >> sweep freq setup results into aliasing or not?
https://designers-guide.org/forum/YaBB.pl?num=1366330112

Message started by Go,TB on Apr 18^th, 2013, 5:08pm

Title: sweep freq setup results into aliasing or not?
Post by Go,TB on Apr 18^th, 2013, 5:08pm

Hello, there

I have a question regarding pnoise simulation setup. The fundamental tone freq of my interest is f0. Following the guideline, the sweep freq is set from 10 to f0/2. The reason given to the choice of f0/2 is because that a sampler with f0 sampling freq is attached to the output in pss/pnoise simulation. The sampler is only for simulation purpose. So the f0/2 looks like a natural choice following the Nyquist Theorem.

However I wonder if this is right. Please check the attached excerpt from Ken Kundert's publication. The noise folds back to the fundamental freq f0 by those harmonics but the overall noise is still wide-band and of course beyond f0/2. So if the sampler at the output still samples at f0/2, the aliasing will occur.

Please correct me if my understanding is not correct at all.

Thank you!