tromeros
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Greece
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Hi, I have some additional questions concerning the MATLAB code. The PSD figure (page 46) in Ken's paper has a frequency range from 300Hz to 100KHz. I simulate a PLL that has a VCO output frequency of 1G and a frequency divide ratio of 4. Because the ratio is small I simulate it for 10us and I set the outstart variable that exist in VCO's code at a value of 1us. In matlab, the frequency range of Sphi that I get, varies from 500Khz to 100MHz which is quite different fron the paper. My questions are: -Does the frequency at the output of the divider(250MHz in my case) affect the frequency range of the psd? -Does the simulation time have an impact in frequncy range? -And finally how can I take the values of Sphi for a lower frequency?
Thank a lot for the help.
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