Common Measurement Settings
R&S
®
FSW
471
User Manual 1173.9411.02 ─ 43
Table 8-2: Optimization parameters in FFT mode
Optimization mode
Description
Dynamic
Optimizes the dynamic range by using the narrowest possible subspan (depending
on the RBW).
The autorange function for the internal IF gain calculation is activated to obtain the
best control range for the A/D converter.
Speed
Optimizes the sweep rate by using the widest possible subspan (depending on the
RBW).
The autorange function for the internal IF gain calculation is deactivated. (Note: set
the reference level accordingly to optimize the control range for the A/D converter).
It is recommended that you set the
to "Auto" to optimize the sweep
rate.
Auto
Uses a medium-sized subspan to obtain a compromise between a large dynamic
range and a fast sweep rate.
The autorange function for the internal IF gain calculation is deactivated. (Note: set
the reference level accordingly to optimize the control range for the A/D converter).
Note: FFT mode and external mixers (R&S
FSW-B21)
The subspan optimization modes "Dynamic" and "Auto" include automatic suppression
of unwanted mixing products. Thus, when using external mixers (R&S
FSW-B21), use
the "Speed" mode to obtain similar results in FFT mode as in frequency sweep mode.
Zero span mode
For zero span measurements, the optimization mode defines the selection of the A/D
converter prefilter.
Table 8-3: Optimization parameters in zero span mode
Optimization mode
Description
Dynamic
The narrowest filter possible (depending on the RBW) is used.
Speed
The widest filter possible (depending on the RBW) is used.
Auto
A medium-sized prefilter is used.
Note: EMI measurements
For EMI measurements (using R&S
FSW-K54), "Dynamic" mode is not supported.
"Auto" mode always uses "Speed" optimization.
Remote command:
Sweep Type
Defines the sweep type.
"Sweep"
In the standard sweep mode, the local oscillator is set to provide the
spectrum quasi analog from the start to the stop frequency.
"Auto"
Automatically sets the fastest available sweep type for the current
measurement (Frequency or FFT). Auto mode is set by default.
Bandwidth, Filter and Sweep Configuration