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printing calculated out put noise from a pnoise simulation

rpanock

 I am trying to print out the results of a pnoise simulation of a vco.  it seems that the only way to do it it is from the calculator.  That optiononly lets you print out the phase noise in dbc/Hz.  I would like the output noise voltage or voltage squared.  Seems like their should be a way since it is calculated for plotting.

  • Have you tried using Results->Print->Noise Contributions in ADE?

    Andrew.

  • Hi rpanock,
     
    Have you tried Results->Print->Noise Summary ?
    This allows you to print out integrated and spot noise for each individual component/contributor.

    You can also use the Results Browser to print Noise results (NF, NFdsb, NFieee, etc) to a table.
     
    best regards,
     
    Tawna

  •  Ok.  thanks.  The results ->Pricnt Noise summary only lets you print spot noise at a given frequency or the integrated nois.  I want a table of total noise vs. frequency to import into matlab.  The results browser is what is needed.  thanks.

  • hi guys,

    this is the closest thread i could found to my current problem, i hope it's ok i put my question here..

    After I run a pss/pnoise on an oscillator

     I printout the noise summary at 1MHz(relative to 1st harmonic). the total spot noise in (V^2/Hz) is 1.6e-13.

    If I log it by 10*log(1.6e-13), I will get -128dB. That’s case 1.

     

    Case 2, is when I plot the pnoise, and at 1MHz, the pnoise plot shows -131.8dBc/Hz.

     Question, should these 2 number match with each other.

    in other word, should the pnoise at 1MHz be agree(or match) the totol spot noise at 1MHz from the print noise summary option?

    i understand the pnoise number is relative to the carrier power where as the total spot noise is an absolute noise.

    can you also tell me how to find the total power of the carrier ( i am not sure if i should include or exclude other harmonics)

    many thanks.

    Frank

  • Frank,

    As the Forum Guidelines suggest, please don't post on the end of an old thread. There's no need in this case as your question doesn't require anything from the earlier thread.

    To find the phase noise in dBc, plot the magnitude of the oscillator output (the same node you specified in the pnoise form) as magnitude, rms (on the direct plot form). Find the value at the 1st harmonic, and then if you calculate:

    20*log10(sqrt(noiseSummaryTotal)/harm1value))

    you'll get the phase noise amount. It's dividing the noise voltage by the RMS value of the appropriate harmonic (typically 1st harmonic).

    Regards,

    Andrew.

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