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Owning Palette: Distortion VIs

Installed With: Sound and Vibration Measurement Suite

Computes the multitone phase of each tone in a multitone signal, the average group delay, and the max deviation of the phase from a straight line. Use a square wave or construct the input signal with component tones evenly spaced in frequency and with zero relative phase between the component tones.

Use the pull-down menu to select an instance of this VI.

Select an instance SVT Phase Linearity (1 Ch)

SVT Phase Linearity (1 Ch)

	desired units specifies the engineering units of the returned measurements. phase units specifies the units for phase measurements. 0 deg (default) 1 rad average group delay units specifies the units for average group delay. 0 deg/Hz (default) 1 s magnitude spectrum units specifies the units for magnitude spectrum. 0 dB (default) 1 Linear
	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	frequency range defines the frequency band of analysis. start frequency specifies the lowest frequency of interest for the analysis band in hertz. Specify a value of -1 to select f0 as the minimum frequency of interest. stop frequency specifies the highest frequency of interest for the analysis band in hertz. The valid range is between 0 and the Nyquist frequency. Specify a value of –1 to select the highest frequency as the maximum frequency of interest.
	magnitude threshold [dB] specifies the minimum amplitude on the magnitude spectrum that a component tone must exceed to be included in the measurement.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	unit labels returns the unit label for each member of desired units. phase unit label returns the unit label for the selected phase units. average group delay unit label returns the unit label for average group delay. magnitude spectrum unit label returns the unit label for magnitude spectrum.
	magnitude spectrum returns the magnitude of the FFT spectrum. f0 returns the start frequency, in hertz, of the spectrum. df returns the frequency resolution, in hertz, of the spectrum. magnitude returns the magnitude of the FFT spectrum.
	phase spectrum returns the measured phase at each tone and the best linear fit to the measured phases.
	max phase deviation returns the measured phase linearity, which is defined as the maximum deviation by the phase-versus-frequency plot from a straight line.
	multitone phase returns the measured frequencies and phases for all tones in scaled signal [EU] with a frequency between start frequency and stop frequency and a magnitude greater than threshold [dB]. frequency [Hz] is the frequency of an individual tone in hertz. phase is the phase of an individual tone.
	spectrum info returns information about the spectrum needed by the Spectrum Extended Measurements VIs, the Waterfall Display VIs, the Distortion VIs, and the Single Tone Measurements VIs. Do not modify the spectrum info values.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	average group delay returns the measured group delay, assuming no group delay distortion.
	phase deviation spectrum returns the measured phase deviation at each tone and the best linear fit to the measured phase deviations.