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analog2000 Junior Member Offline Posts: 21	Relationship between phase noise and output Jun 15^th, 2007, 9:53am Hello, Would anyone please clarify the difference between the phase noise or jitter calcualted by Spectre RF (pnoise) and the output noise summary (in volts) also calcuated by the pnoise analysis ? thanks a million analog2000
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didac

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Re: Relationship between phase noise and out
Reply #1 - Jun 15^th, 2007, 1:23pm

Hi analog2000,
You are mixing two different concepts, phase noise and jitter are effects related to innacuracies of frequency in oscillators(jitter for digital circuits, phase noise in analog oscillators usually). Output noise(in V/sqrt(Hz) or V^2/Hz) is the measurement of thermal,flicker,shot,popcorn noise whetever applies in your case. In other words the first relates more to synchronization(in jitter case for digital systems) or undesired mixing(for rf front-end for phase noise,caused by the fact that you didn't have a true dirac delta in an oscillator) and output noise relates to the sensitivity of the system(which also causes that engineers have work, if noise didn't exist i communications systems will be more easy to design).
Hope it helps this explanation

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« Last Edit: Jun 16^th, 2007, 6:48am by didac »

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analog2000

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Re: Relationship between phase noise �and output
Reply #2 - Jun 17^th, 2007, 12:58pm

Thanks didac for your response.
In Spectre RF you can simulate both phase noise/jitter and output noise using the print summary statements. This is if you do a pnoise simulation. I am just trying to correlate the results of both results i.e. print summary output which allows one to integrate the noise in a given bandwidth and phase noise which allows one to simulate jitter also in a certain bandwidth
thanks
analog2000

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didac Senior Member Offline There's a million ways to see the things in life Posts: 247 manresa,spain	Re: Relationship between phase noise and out Reply #3 - Jun 17^th, 2007, 1:01pm Hi, I usually use the GUI of spectreRF,plot the waveform and open the calculator, with the calculator you can select the waveform and use the integration function(integ if I don't remember bad,I don't have Cadence opened right now)
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