phase noise simulation setup for PFD/CP

[boshiouke]

pfd cp noise

Does anyone know the difference between different "noise type" in Pnoise analysis, i.e "sources", "time domain", "modulated", when simulating for PFD/CP? I'd greatly appreciate it if anyone can show me how to set up the PNoise analysis for PFD/CP using those different "noise type"? I heard that using "timedomain" would result in better phase noise result than "sources". Is that right? Thank you so much.

 

[rfsystem]

There is not "better", there is only correct, or less error prone method to do PFD/CHP phase noise analysis.

If you want to do PN analysis you have to separate the edge jitter controlling the current switches from the current noise. The jitter could be extracted by Pnoise with the time domain method. So the Pnoise analyse the spectral distribution at a specific time point. The best time point is where the logic threshold is. The current noise is limited in the best case by the shot noise. Because of the periodic nature of the current pulses the average noise up to half sampling frequency is proportional to the current on time and higher frequency noise components gets folded from higher frequencies to less than half the reference.

I think the second noise contribution could simulated by Pnoise but with the standard method. In this case you have to use a PFD/CHP in locked condition.