Rohde & Schwarz FSWP Series - FFT Length; Window Overlap

Configuration
R&S
®
FSWP
62User Manual 1177.5856.02 ─ 07
Note that if the advanced FFT mode is used, the RBW settings are not available.
For more information see Chapter 4.5.4, "Frequency Resolution of FFT Results -
RBW", on page 32.
Transformation Algorithm ← Advanced FFT mode / Basic Settings
Defines the FFT calculation method.
"Single"
One FFT is calculated for the entire record length; if the FFT Length
is larger than the record length, zeros are appended to the captured
data.
"Averaging"
Several overlapping FFTs are calculated for each record; the results
are combined to determine the final FFT result for the record. The
number of FFTs to be averaged is determined by the Window Overlap
and the Window Length .
Remote command:
[SENSe:]IQ:FFT:ALGorithm on page 130
FFT Length ← Advanced FFT mode / Basic Settings
Defines the number of frequency points determined by each FFT calculation. The more
points are used, the higher the resolution in the spectrum becomes, but the longer the
calculation takes.
In advanced FFT mode, the number of measurement points is set to the FFT length
automatically.
Note: If you use the arrow keys or the rotary knob to change the FFT length, the value
is incremented or decremented by powers of 2.
If you enter the value manually, any integer value from 3 to 524288 is available.
Remote command:
[SENSe:]IQ:FFT:LENGth on page 130
Window Function ← Advanced FFT mode / Basic Settings
In the I/Q analyzer you can select one of several FFT window types.
The following window types are available:
●
Blackman-Harris
●
Flattop
●
Gauss
●
Rectangular
●
5-Term
Remote command:
[SENSe:]IQ:FFT:WINDow:TYPE on page 131
Window Overlap ← Advanced FFT mode / Basic Settings
Defines the part of a single FFT window that is re-calculated by the next FFT calcula-
tion when using multiple FFT windows.
Remote command:
[SENSe:]IQ:FFT:WINDow:OVERlap on page 131
Data Acquisition and Bandwidth Settings