lwzunique wrote on Jan 18th, 2017, 5:55pm:the output sequence of "pllMMLib/SDM_MASH_3rd_111_macro" is -3 to 4,
No. It is no more than range of output codes.
You have not confirmed output sequences at all.
lwzunique wrote on Jan 18th, 2017, 5:55pm:and its average value is the input fractional data, I think it is valid.
Maybe, output sequences are correct.
lwzunique wrote on Jan 18th, 2017, 5:55pm:Definition of fft() is different between Keysight ADS PostProcessing and MathWorks MATLAB.
Study fft().
Definition of fft() is same between Keysight ADS PostProcessing and Cadence ADE PostProcessing.
lwzunique wrote on Jan 18th, 2017, 5:55pm:1.why my curve shape is not like yours?
http://www.designers-guide.org/Forum/Attachments/QQ20170119103715.jpg seems reasonable.
This PSD is for delta_N, that is, frequency, so slope is +60dB/dec=2*order*20dB/dec.
PSD for phase is +40dB/dec=2*(order-1)*20dB/dec.
See
http://www.designers-guide.org/Forum/YaBB.pl?num=1444923186/6#6lwzunique wrote on Jan 18th, 2017, 5:55pm:2.why the magnitude of the curves are so different from each other?
Simply your setting for psd() is not appropriate.
lwzunique wrote on Jan 18th, 2017, 5:55pm:3.when do PSD, we should also apply dB10 to PSD function, right?
Right.
lwzunique wrote on Jan 18th, 2017, 5:55pm:4.why should we choose hanning window,
See Appendix-A of the followings.
https://www.amazon.com/Understanding-Delta-Sigma-Converters-Richard-Schreier/dp/...lwzunique wrote on Jan 18th, 2017, 5:55pm:and if the window size surpass 1024, the psd result will be wrong, why?
Study psd().
See
http://www.designers-guide.org/Forum/YaBB.pl?num=1405235104lwzunique wrote on Jan 18th, 2017, 6:41pm:another question: let make it question 5: what do the smooth factors mean, it doesn't work when I changed the value?
I can not understand what you want to mean at all.