Spectral density

  • Thread starter Przem
  • Start date
Spectral density?

How to get spectral density (e.g. of voltage noise) from a fast Fourier transform of a signal????
Last edited:


Science Advisor
Are you doing this by hand or via some kind of software? A PSD is pretty much an equivilent to doing an RSS of the signal.

If you contact Tom Irvine at VibrationData.com, he has some great papers and references on this subject.


i presume you mean power sprectrum or energy spectrum which is the Fourier Transform of the autocorrelation function. no?

i think you want the magnitude square of the FFT (there's another scaling factor involved.). later i'll post a more exact relationship.

gotta go.

r b-j
I want to do it via Fortran 90 and I have main problem with this scaling factor.

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