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Is it possible to view the source code of a SpectreRF function? (Read 66 times)

StevenH

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Is it possible to view the source code of a SpectreRF function?
Apr 30^th, 2021, 3:32am

There is a function in SpectreRF called "pn", it takes as an argument the results of a noise analysis and outputs the phase noise data at a given frequency (for example, pn('hbnoise)).

Is it possible to view the SKILL source code of this function to see how it's implemented? I'm more interested in the formula/convention that's used to define the phase noise (measured in dBc/Hz) rather than the code itself.

Say I do a PM noise analysis, and let's call the phase modulation magnitude spectrum outputted A in (V/sqrt(Hz)). Which mathematical formula does pn apply on A? Is it 10log(A^2/power(harmonic(1))? or 10log(A^2/harmonic(1)^2)? or is it something else?

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Andrew Beckett

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Re: Is it possible to view the source code of a SpectreRF function?
Reply #1 - Dec 29^th, 2021, 7:44am

No you can't see the source for it, but it's computing:

db20(getData("out" "pnoise_pm") / (harmonic(v("pos" ?result "pss")-v("neg" ?result "pss") harmNum) / sqrt(2)))

where "pnoise_pm" is whatever the noise analysis was and "pss" is whatever the large-signal analysis was, and the "pos" and "neg" are the specified positive and negative output nodes for the pnoise analysis (if the negative node isn't specified, it defaults to ground).

The 'out" is the normal output noise from the analysis (it's always called "out"), so is in V/sqrt(Hz)

Andrew

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