Rohde & Schwarz FSW Series, User Manual

Page: 87 / 371

Configuration
R&S
®
FSW-K7
87 User Manual 1173.9240.02 ─ 17
Note that for input from the External Mixer (R&S FSW-B21) the maximum reference
level also depends on the conversion loss; see the R&S FSW I/Q Analyzer and I/Q
Input User Manual for details.
Remote command:
DISPlay[:
​
WINDow<n>]:
​
TRACe:
​
Y[:
​
SCALe]:
​
RLEVel
​
on page 234
Shifting the Display (Offset) ← Reference Level
Defines an arithmetic level offset. This offset is added to the measured level irrespec-
tive of the selected unit. The scaling of the y-axis is changed accordingly.
Define an offset if the signal is attenuated or amplified before it is fed into the
R&S
FSW so the application shows correct power results. All displayed power level
results will be shifted by this value.
Note, however, that the Reference Level value ignores the "Reference Level Offset". It
is important to know the actual power level the R&S FSW must handle.
To determine the required offset, consider the external attenuation or gain applied to
the input signal. A positive value indicates that an attenuation took place (R&S
FSW
increases the displayed power values) , a negative value indicates an external gain
(R&S
FSW decreases the displayed power values).
The setting range is ±200 dB in 0.01 dB steps.
Remote command:
DISPlay[:
​
WINDow<n>]:
​
TRACe:
​
Y[:
​
SCALe]:
​
RLEVel:
​
OFFSet
​
on page 235
Unit ← Reference Level
The R&S FSW measures the signal voltage at the RF input. In the default state, the
level is displayed at a power of 1 mW (= dBm). Via the known input impedance (50 Ω
or 75 Ω, see
"Impedance" on page 57), conversion to other units is possible. The fol-
lowing units are available and directly convertible:
●
dBm
●
dBmV
●
dBμV
●
dBμA
●
dBpW
●
Volt
●
Ampere
●
Watt
Remote command:
INPut:
​
IMPedance
​
on page 183
CALCulate<n>:
​
UNIT:
​
POWer
​
on page 234
Setting the Reference Level Automatically (Auto Level) ← Reference Level
Automatically determines the optimal reference level for the current input data. At the
same time, the internal attenuators and the preamplifier (for analog baseband input:
the full scale level) are adjusted so the signal-to-noise ratio is optimized, while signal
compression, clipping and overload conditions are minimized.
In order to do so, a level measurement is performed to determine the optimal reference
level.
Input and Frontend Settings