Calculate:fft - Rigol DS4000E Series Programming Manual

RIGOL

:CALCulate:FFT

Command List:
:CALCulate:FFT:HCENter

:CALCulate:FFT:HOFFset

:CALCulate:FFT:HSCaLe

:CALCulate:FFT:HSPan

:CALCulate:FFT:SOURce

:CALCulate:FFT:SPLit

:CALCulate:FFT:VOFFset

:CALCulate:FFT:VSCale
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:CALCulate:FFT:VSMode
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:CALCulate:FFT:WINDow
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:CALCulate:FFT:HCENter
Syntax
:CALCulate:FFT:HCENter <center>
:CALCulate:FFT:HCENter?
Description
Sets or queries the center frequency of FFT operation. The default unit is Hz.
Parameter
Name Type
<center> Real
Return Format
The query returns the center frequency in scientific notation.
:CALCulate:FFT:HOFFset
Syntax
:CALCulate:FFT:HOFFset <offs>
:CALCulate:FFT:HOFFset?
Description
Sets or queries the horizontal position of the FFT operation waveform. The default unit is Hz.
Parameter
Name Type
<offs> Real
Remarks
The range of <offs> is related to the on/off status of the anti-aliasing function, FFT sample rate (Sa),

and FFT horizontal scale (Hspan). The relationship is shown as below:
When the anti-aliasing function is disabled, the range of <offs> is from (max{-0.5 x Sa, -14 x Hspan})
to (0.5 x Sa).
When the anti-aliasing function is enabled, the range of <offs> is from (max{-0.4 x Sa, -14 x Hspan})
to (0.4 x Sa).
Note: max{A, B} indicates selecting a greater value from A and B.
FFT Sample Rate = Number of Pixels Per Grid Horizontally/Horizontal Time Base

Wherein, Number of Pixels Per Grid Horizontally is related to the on/off status of FFT anti-aliasing
function. When the function is disabled, Number of Pixels Per Grid Horizontally is 50; when enabled, it
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Range
FFT horizontal position + 7 x FFT horizontal scale
Range
Refer to Remarks
Chapter 2 Command System
Default
8.750 MHz
Default
0
DS4000E Programming Guide