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Computes the single-sided, scaled, auto power spectrum of a time-domain signal.

Details  Example

	Signal specifies the input time-domain signal, usually in volts. The time-domain record must contain at least three cycles of the signal for a valid estimate.
	dt is the sample period of the time-domain signal, usually in seconds. LabVIEW defines dt as 1/fs, where fs is the sampling frequency of the time-domain signal.
	Power Spectrum returns the single-sided power spectrum. If the input Signal is in volts (V), Power Spectrum has units of volts-rms squared (Vrms2). If the input Signal is not in volts, Power Spectrum has units of the input signal unit-rms squared.
	df is the frequency interval of the power spectrum in hertz, if dt is in seconds.

Auto Power Spectrum Details

This VI computes the power spectrum using the following equation.

where n is the number of points in the Signal and * denotes the complex conjugate. This VI then converts the power spectrum into a single-sided power spectrum.

Example

Refer to the FFT and Power Spectrum Units VI in the labview\examples\measure\maxmpl.llb for an example of using the Auto Power Spectrum VI.