:FUNCtion<m> Commands
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Keysight InfiniiVision M9241/42/43A PXIe Oscilloscopes SCPI Programmer's Guide
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:FUNCtion<m>[:FFT]:DETection:TYPE
Command Syntax
:FUNCtion<m>[:FFT]:DETection:TYPE <type>
<type> ::= {OFF | SAMPle | PPOSitive | PNEGative | NORMal | AVERage}
<m> ::= 1-4 in NR1 format
The :FUNCtion<m>[:FFT]:DETection:TYPE command sets the FFT detector
decimation type.
Detectors give you a way of manipulating the acquired data to emphasize different
features of the data. Detectors reduce (decimate) the number of FFT points to at
most the number of specified detector points. In this reduction, sampled FFT
points are bucketized, that is, split into a number of groups that equals the
specified number of detector points. Then, the points in each bucket are reduced
to a single point according to the selected detection type. The detector types are:
• OFF — No detector is used.
• SAMPle — Takes the point nearest to the center of every bucket.
• PPOSitive (+ Peak) — Takes the most positive point in every bucket.
• PNEGative (- Peak) — Takes the most negative point in every bucket.
• AVERage — Takes the average of all points in every bucket.
• NORMal — Implements a rosenfell algorithm. This method to picks either the
minimum or maximum sample in every bucket depending on whether the data
is monotonically increasing, decreasing, or varying. For details, see the
Spectrum Analysis Basics application note
at www.keysight.com.
When detectors are used, the FFT's output is decimated, and any analysis is
performed on the reduced or detected data set.
Query Syntax
:FUNCtion<m>[:FFT]:DETection:TYPE?
The :FUNCtion<m>[:FFT]:DETection:TYPE? query returns the FFT detector type
setting
Return Format
<type><NL>
<type> ::= {OFF | SAMPle | PPOSitive | PNEGative | NORMal | AVERage}
See Also
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