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Converts either the power, amplitude, or gain (amplitude ratio) spectrum to alternate formats including Log (decibel and dbm) and spectral density.

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spectrum in

On input, the spectrum of a time domain signal. It can be of type specified by the spectrum type selector.

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spectrum type

Type of spectrum.

Power (Vrms^2)

Sets the type of spectrum in to power.

Amplitude (Vrms)

Sets the type of spectrum in to amplitude.

Gain (amplitude ratio)

Sets the type of spectrum in to gain.

Default: Power (Vrms^2)

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log?

Linear or log spectrum output.

Linear 0
DB 1
DBm 2

Default: 1—DB

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display unit

The output unit for the spectrum. You can set display unit to one of the values listed in the following table. The last four selections are amplitude spectral density (4,5) and power spectral density (6,7). The control cluster window constants contains constants for the selected window (from the Scaled Time Domain Window node). You need this input only when you use the spectral density output formats (the last four output unit selections).

Vrms

Displays units in volts rms.

Vpk

Displays units in volts peak.

Vrms^2

Displays units in squared rms.

Vpk^2

Displays units in squared peak.

Vrms/rtHz

Displays units in rms per root Hz.

Vpk/rtHz

Displays units in peak per root Hz.

Vrms^2/Hz

Displays units in squared rms per Hz.

Vpk^2/Hz

Displays units in squared peak per Hz.

Default: Vrms

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df

The line frequency interval of the input spectrum. You need this input only when you use the spectral density output formats (the last four display unit selections).

Default: 1.0

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window constants

The window constants for the selected window. You obtain window constants from the Scaled Time Domain Window node. You need this input only when you use the spectral density output formats, the last four display unit selections.

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eq noise BW

The equivalent noise bandwidth (ENBW) of the window that was used. You can use this value to divide a sum of individual power spectra of the power spectrum or to compute the power in a given frequency span.

Default: 1.0

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coherent gain

The inverse of the scaling factor applied to the window.

Default: 1.0

Default: rectangular window (no window)

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signal unit

A string containing the unit of the input time domain signal. If the original signal unit was in volts, then this input should contain the letter V for volts.

Default: V

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spectrum out

On output, the spectrum in the form specified by log? and display units.

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spectrum unit

A string containing the unit of the output spectrum. If the output spectrum is in decibels form, the unit is prepended by dB.