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Spectral density

  1. Jun 20, 2005 #1
    Spectral density?

    How to get spectral density (e.g. of voltage noise) from a fast Fourier transform of a signal????
    Last edited: Jun 20, 2005
  2. jcsd
  3. Jun 20, 2005 #2


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    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.
  4. Jun 20, 2005 #3


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    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
  5. Jun 22, 2005 #4
    I want to do it via Fortran 90 and I have main problem with this scaling factor.
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