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https://designers-guide.org/forum/YaBB.pl Measurements >> Phase Noise and Jitter Measurements >> Phase-Noise Conversion to Jitter using Matlab https://designers-guide.org/forum/YaBB.pl?num=1291795277 Message started by pcardoso73 on Dec 8th, 2010, 12:01am |
Title: Phase-Noise Conversion to Jitter using Matlab Post by pcardoso73 on Dec 8th, 2010, 12:01am Hi all, I am doing a Phase-Noise on a Pierce XTAL oscillator. I did it on Cadence using PSS + PNOISE. I have exported the data to Matlab and now I want to convert this data into Jitter. How can I integrate the Phase noise curve ? Please bear in mind that I am using log units, so dBc/Hz vs frequency. Thanks in advance. Best regards, Pedro Cardoso |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by raja.cedt on Dec 8th, 2010, 6:25am hi, please integrate in spectra RF only, why you want to move to MATLAB? Thanks. |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by pcardoso73 on Dec 8th, 2010, 7:15am Hi, Thanks for your answer, but I have already done that and the result is not what I was expecting. In this case I used the cslculator, and the function 'integ' to integrate. Once yy the units of the are dBc/Hz and for xx axis Hz (frequency), should I do any manipulation of the data prior to integration ? That is, should I convert to linear units the plot, and only then calculate the integral ? As the phase noise is given in dBc/Hz, I guess I sould calculate the power of the carrier and add it to the yy axis. Does this make any sense ? Best regards, Pedro |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by raja.cedt on Dec 8th, 2010, 8:02pm hi, first convert y axis into linear just bu 10^(L/10) and now this is corresponding to single side band so multiply with 2 to get both side bands. Now integrate so you will get RMS phase error. then divide this number with 2*3.14*f0. Finally you will end up with RMS jitter. Thanks. |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by Mayank on Dec 16th, 2010, 12:19am Quote:
If you want Period Jitter, then scale with an appripriate weighing function & integrate. As to what weighing function you wanna use, there have been several metrics from different theoretical physicists lk Demir, Zanchi, etc. which are basically related to sinc function.[FT of a rectangular time window] About Cadence's analog artist calculator, it provides the values for long term as well as short term period jitter correctly provided you are feeding the correct data. --M |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by Frank Wiedmann on Dec 16th, 2010, 12:34am You can find the formula for k-cycle jitter (Jc) at http://www.designers-guide.org/Forum/YaBB.pl?num=1224609785/9#9. |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by pcardoso73 on Dec 17th, 2010, 7:32am Than you very much to all of you. Cheers, Pedro |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by Dinesh Agarwal on Mar 1st, 2011, 5:40pm phase noise with unit v2/Hz integrated will have unit of v2. My doubt is how it is converted in jitter with time unit (second) , dividing by 2*3.14*f. pls give few details |
Title: Re: Phase-Noise Conversion to Jitter using Matlab Post by pcardoso73 on Aug 6th, 2011, 3:29am Dear all, I have still some problems with integration. I want to calculate Jcc jitter. So I am doing a PNOISE + PSS simulation. But what gives me some doubts about the integration limit is that the Jcc varies a lot, due to the harminc's presence (I think so). So my question is, can I integrate till one fraction of fo/2 ? Which range would give me the most accurate result ? I think that at fo/2 I am couting the noise of the harmonic. Is this correct ? Best regards, Pedro |
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