Computes the marginal integration of a signal by integrating the spectrogram of the signal along the time axis or the frequency axis.


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Inputs/Outputs

  • c2ddbl.png spectrogram —

    spectrogram specifies the quadratic time-frequency representation of a signal.

    Use the Time Frequency Spectrogram VIs to compute the spectrogram of the signal.

  • cfxdt.png scale info —

    scale info specifies the time scale information and the frequency scale information of the time-frequency representation.

  • cerrcodeclst.png error in (no error) —

    error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

  • icclst.png frequency marginal integral —

    frequency marginal integral returns the result of integrating the spectrogram along the time axis, or the integral of each column of spectrogram. frequency marginal integral is equivalent to the smoothed power spectrum of the signal. The power spectrum reveals how the power of the signal changes over frequency.

    The following equation defines the frequency marginal integration: where is the spectrogram of the signal.

  • idbl.png f0 —

    f0 returns the lowest value of the frequency bins in hertz.

  • idbl.png df —

    df returns the interval between the frequency bins in hertz.

  • i1ddbl.png spectrum —

    spectrum returns the smoothed power spectrum at each frequency bin.

  • icclst.png time marginal integral —

    time marginal integral returns the result of integrating the spectrogram along the frequency axis, or the integral of each row of spectrogram. time marginal integral is equivalent to the smoothed instantaneous power of the signal. The instantaneous power reveals how the power of the signal changes over time.

    The following equation defines the time marginal integration: where is the spectrogram of the signal.

  • idbl.png t0 —

    t0 returns the lowest value of the time bins in seconds.

  • idbl.png dt —

    dt returns the interval between the time bins in seconds.

  • i1ddbl.png power —

    power returns the smoothed instantaneous power at each time bin.

  • ierrcodeclst.png error out —

    error out contains error information. This output provides standard error out functionality.

    • TFA Marginal Integration Details

    The spectrogram can result from any Time Frequency Spectrogram VI.

    If you use the Wigner-Ville Distribution to compute the marginal integration, you can prove that

    and

    Examples

    Refer to the Marginal Condition VI in the labview\examples\Time Frequency Analysis\TFAFunctions directory for an example of using the TFA Marginal Integration VI.