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"Include FM noise" has any meaning ?

Question asked by TNAKA on Jun 27, 2003
Latest reply on Jul 8, 2003 by wrivas
There is a button for "Include FM noise (osc. only)" in Noise(1) tab of HB controller.
But we can always get both "pnmx" and "pnfm" as phase noise result
regardless of setting this "Include FM noise". On the other hand, there is no such button in NoiseCon.

So my question is:
"FM_Noise=yes" has any meaning as option of HB analysis statement ?

Before MDS7.0, this "FM_Noise=yes" had surely meaning,
since we couldn't get "pnmx" and "pnfm" separately.

But after MDS7.1 including current ADS, we can get "pnmx" and "pnfm" separately.
Of course, we can get relative vnoise spectrum(NC2.Vout.noise) as phase noise result,
but SSB_phase_noise calculated by this relative vnoise spectrum(NC2.Vout.noise) is same as "pnmx" regardless of "FM_Noise=yes or no".

  MDS70_SSB_phase_noise=vs(dB(NC2.Vout.noise)-dB(HB.Vout[1]/sqrt(2)), abs(NC2.noisefreq))


"FM_Noise=yes or no" is a vestiges from legacy and inappropriate interpretation of phase noise ?  

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