noiseless
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As expressed in Ken's “Predicting the phase noise and jitter of PLL-based frequency synthesizers”, in order to simulate in the phase domain, pfd-cp and divider phase noise parameters should be extracted first, then use it to do the simulation. However, I am confused about how to do it will get right result. 1.for example, for the divider, we know use jitter option of the PNoise to do the jitter simulation. But how to do to get phase noise? I tried to use equation (35) to do the compare, which tdomain output noise as Sn(f), Jee result as SΦ(f). However, they are not equal. 2. for the pfd-cp simulation, I use PNoise to do the simulation, the script is as below analysis('pnoise ?sweeptype "relative" ?relharmnum "1" ?start "100" ?stop "50M" ?dec "30" ?maxsideband "30" ?oprobe "/IPRB0" ?iprobe "" ?refsideband "" ) analysis('pss ?fund "10M" ?harms "10" ?errpreset "moderate" ?tstab "200n" ) I use Iprobe to sense the current noise, which connected to a voltage source to bias the DC voltage. However, the result is somewhat weird (see the attached pic). There is some spurs in the black circle and there is no apparent noise bandwidth there as shown in Ken's paper. My setup is right or not? appreciate any comments
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