VCO waveform and phase noise

[happsky]

Dear all:
may I ask a problem about wave of vco and it Phase noise?
If i get the waveform(using trans simulation) ,how can I know it's phase noise. FFT or other method??

thank you very much~

 

[maharaja1989nellai]

Hi..
if u want to find the values of phase noise of VCO you must run PSS analysis and phase noise analysis together..

 

[happsky]

But In my view,the phase noise is calculate from the waveform.

Hi..
if u want to find the values of phase noise of VCO you must run PSS analysis and phase noise analysis together..

 

[volker_muehlhaus]

Yes, in theory the spectrum can be calculated from the waveform.

However, phase noise very close to the carrier requires a waveform for FFT over an extremely long period of time.

 

[happsky]

Thank you very much

Yes, in theory the spectrum can be calculated from the waveform.

However, phase noise very close to the carrier requires a waveform for FFT over an extremely long period of time.