:MEASure:FFT:FPSDensity

FFT Power Spectral Density Commands

Command Syntax

:MEASure:FFT:FPSDensity

Query Syntax

:MEASure:FFT:FPSDensity?

Description

Measures the power of the FFT within the band specified referenced to 1 Hz.

Multiple bands may be measured simultaneously using multiple measurements.

To set up FFT function waveforms, see :FUNCtion:FOPerator.

You can specify the frequency band using these commands:

The query form of the command returns the measured value.

Measurement Ready?

To confirm that the measurement is ready to read, you can query the measurement's status:

if ('CORR' in Infiniium.query(':MEASure:FFT:FPSDensity:STATus?')):
	measurement = Infiniium.query(':MEASure:FFT:FPSDensity?')

If averaging is turned on (:ACQuire:SMODe AVERage), you can also confirm if the measurement result is ready by comparing the number of specified averages (:ACQuire:COUNt?) versus the number of measurement sweeps that have occurred (:ACQuire:COUNt?). The technique uses the :COUNt? common measurement query. For example,

if (Infiniium.query(':MEASure:FFT:FPSDensity:COUNt?') >= Infiniium.query(':ACQuire:COUNt?')):
	measurement = Infiniium.query(':MEASure:FFT:FPSDensity?')

You can also use an acquisition limit test to test that a number of waveforms or samples have completed before returning a measurement. Refer to the :LTESt:ACQuire:CTYPe command.

Querying Measurement Results and Statistics

You can query measurement results using the :MEASure:FFT:FPSDensity? query after making the proper instance settings.

If a measurement is installed into Results table (using the :MEASure:FFT:FPSDensity command) and you have made the proper instance settings, you can query statistics using common child queries.

Also, you can query measurement results and statistics directly from the Results table (without having to make the proper instance settings beforehand). See Querying Measurement Results and Statistics.