FFT Power Spectrum and PSD (Power Spectrum » Continuous) (G Dataflow)

A value that affects the output coefficients when window type is Kaiser, Gaussian, or Dolph-Chebyshev.

If window type is any other type of window, this node ignores this input.

This input represents the following information for each type of window:

• Kaiser—Beta parameter
• Gaussian—Standard deviation
• Dolph-Chebyshev—The ratio of the main lobe to the side lobe, s, expressed in decibels

Default: NaN—Causes this node to set beta to 0 for a Kaiser window, the standard deviation to 0.2 for a Gaussian window, and s to 60 dB for a Dolph-Chebyshev window

Time-domain window to apply to the signal.

Default: Hanning

A Boolean that specifies whether the node restarts the selected averaging process.

When you call this node for the first time, the averaging process restarts automatically. A typical case when you restart averaging is when a major input change occurs in the middle of the averaging process.

Default: False

Input signal.

This input accepts the following data types:

• Waveform
• Waveform in complex double-precision, floating-point numbers
• 1D array of waveforms
• 1D array of waveforms in complex double-precision, floating-point numbers

A Boolean that specifies whether this node returns the results in decibels.

Default: False

Settings that define how this node computes the averaging.

averaging mode

The mode this node uses to compute the averaging.

Name	Description
No averaging	Does not use averaging.
Vector averaging	Uses vector averaging.
RMS averaging	Uses RMS averaging.
Peak hold	Uses peak hold averaging.

Default: No averaging

weighting mode

Weighting mode for RMS and vector averaging.

Name	Description
Linear	Uses linear weighting.
Exponential	Uses exponential weighting.

Default: Exponential

number of averages

Number of averages to use for RMS and vector averaging.

If weighting mode is Exponential, the averaging process is continuous. If weighting mode is Linear, the averaging process stops after this node computes the specified number of averages.

Default: 10

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error	error in contains an error
If no error occurred before the node runs, the node begins execution normally. If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.	If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

Averaged power spectrum of the input signal.

This output can return a cluster or a 1D array of clusters.

f0

Start frequency, in Hz, of the spectrum.

df

Frequency resolution, in Hz, of the spectrum.

magnitude

Magnitude of the averaged power spectrum.

Determining the unit of measurement

If the input signal is in volts (V), the unit of this output is volts-rms squared (V_rms² ) for power spectrum. If the input signal is not in volts, the units of this output is the input signal unit-rms squared for power spectrum. If this node returns results in decibels, and the input signal is in volts, the units of this output is dBV for power spectrum.

A Boolean that indicates whether the number of averages this node completed is greater than or equal to the specified number of averages.

averaging done is True if averaging mode is No averaging.

Number of averages this node completed.

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error	error in contains an error
If no error occurred before the node runs, the node begins execution normally. If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.	If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.