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Owning Palette: Spectrum Extended Measurements VIs

Installed With: Sound and Vibration Measurement Suite

Compensates FFT and frequency response phase spectra for time delay. You can introduce time delays with the DUT, data acquisition hardware, and measurement analysis. Compensation in this VI is restricted to linear phase resulting from a pure time delay. The data type you wire to the phase spectrum input determines the polymorphic instance to use.

Details  

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

Select an instance SVFA Compensate Phase for Time Delay 1 ChSVFA Compensate Phase for Time Delay N ChSVFA Compensate Phase for Time Delay 1 Ch (XY spectrum)SVFA Compensate Phase for Time Delay N Ch (XY spectrum)

SVFA Compensate Phase for Time Delay 1 Ch

	phase spectrum contains the frequency spacing and the phase of the spectrum. The units for phase spectrum are specified in spectrum info in. f0 specifies the start frequency, in hertz, of the spectrum. df specifies the frequency resolution, in hertz, of the spectrum. phase specifies the phase of the frequency response.
	delay [s] specifies the amount of time delay compensation to apply to phase spectrum. A positive delay results in compensation that reduces the slope of the plot of unwrapped phase versus frequency. For example, you can compute the delay from physical measurements, average group delay measurements, or the difference between the start times, t0, of two waveforms.
	spectrum info specifies the properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	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.
	compensated phase spectrum returns the phase spectrum compensated for the specified delay. At each frequency, f, the compensated phase = input phase + (delay*360*f). f0 returns the start frequency, in hertz, of the spectrum. df returns the frequency resolution, in hertz, of the spectrum. phase returns the phase of the frequency response.
	unit label returns the selected engineering units.
	dup spectrum info returns spectrum info unchanged. Do not modify the dup spectrum info values. The properties contained in spectrum info out include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density.
	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.

SVFA Compensate Phase for Time Delay N Ch

	phase spectra contains the frequency spacing and the phase for each spectrum. The units for phase spectra are specified in spectrum info in. f0 specifies the start frequency, in hertz, of the spectrum. df specifies the frequency resolution, in hertz, of the spectrum. phase specifies the phase of the frequency response.
	delays [s] specifies the amount of time delay compensation to apply to each phase spectrum. A positive delay results in compensation that reduces the slope of the plot of unwrapped phase versus frequency. You can compute the delay from physical measurements, average group delay measurements, or the difference between the start times, t0, of two waveforms.
	spectrum info specifies the properties of the computed spectrum. spectrum info specifies the properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	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.
	compensated phase spectra returns the phase spectra compensated for the specified delays. At each frequency, f, the compensated phase = input phase + (delay*360*f). f0 returns the start frequency, in hertz, of the spectrum. df returns the frequency resolution, in hertz, of the spectrum. phase returns the phase of the frequency response.
	unit labels returns the unit label for each channel.
	dup spectrum info returns spectrum info unchanged. Do not modify the dup spectrum info values. The properties contained in spectrum info out include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density.
	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.

SVFA Compensate Phase for Time Delay 1 Ch (XY spectrum)

	phase spectrum contains the frequency values and the phase of the spectrum. The units for phase spectrum are specified in spectrum info in. frequency specifies the frequency of the phase spectrum. phase specifies the phase of the frequency response.
	delay [s] specifies the amount of time delay compensation to apply to phase spectrum. A positive delay results in compensation that reduces the slope of the plot of unwrapped phase versus frequency. For example, you can compute the delay from physical measurements, average group delay measurements, or the difference between the start times, t0, of two waveforms.
	spectrum info specifies the properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	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.
	compensated phase spectrum returns the phase spectrum compensated for the specified delay. At each frequency, f, the compensated phase = input phase + (delay*360*f). frequency returns the frequency of the phase spectrum. phase returns the phase of the frequency response.
	unit label returns the selected engineering units.
	dup spectrum info returns spectrum info unchanged. Do not modify the dup spectrum info values. The properties contained in spectrum info out include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density.
	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.

SVFA Compensate Phase for Time Delay N Ch (XY spectrum)

	phase spectra contains the frequency values and the phase of each spectra. The units for phase spectra are specified in spectrum info in. frequency specifies the frequency of the phase spectrum. phase specifies the phase of the frequency response.
	delays [s] specifies the amount of time delay compensation to apply to each phase spectrum. A positive delay results in compensation that reduces the slope of the plot of unwrapped phase versus frequency. You can compute the delay from physical measurements, average group delay measurements, or the difference between the start times, t0, of two waveforms.
	spectrum info specifies the properties of the computed spectrum. spectrum info specifies the properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	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.
	compensated phase spectra returns the phase spectra compensated for the specified delays. At each frequency, f, the compensated phase = input phase + (delay*360*f). frequency returns the frequency of the phase spectrum. phase returns the phase of the frequency response.
	unit labels returns the unit label for each channel.
	dup spectrum info returns spectrum info unchanged. Do not modify the dup spectrum info values. The properties contained in spectrum info out include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density.
	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.

SVFA Compensate Phase for Time Delay Details

A delay through a DUT results in a negatively sloped phase spectrum for the DUT frequency response, or response divided by stimulus. Compensation of a phase spectrum for a positive delay increases the slope of the phase spectrum. The compensated spectra, at each frequency, f, is given by phase_out = phase_in + (delay*360*f), for phase in degrees.