Rohde & Schwarz FSW13, User Manual

Page: 393 / 1150

Common Measurement Settings
R&S
®
FSW
393 User Manual 1173.9411.02 ─ 19
● "Signal Tracking Bandwidth": the frequency range around the center frequency
to be tracked
● "Signal Tracking Threshold": the minimum level the trace must reach to be
detected as a maximum
● "Signal Tracking Trace": the trace to be tracked
3. Activate signal tracking by selecting "State: ON".
After each sweep, the center frequency is set to the maximum signal found within
the searched bandwidth. If no maximum signal above the defined threshold value
is found in the searched bandwidth, the center frequency remains unchanged. The
search bandwidth and the threshold value are shown in the diagram by red lines
which are labeled as "TRK".
6.4 Amplitude and Vertical Axis Configuration
In the Spectrum application, measurement results usually consist of the measured sig-
nal levels (amplitudes) displayed on the vertical (y-)axis for the determined frequency
spectrum or for the measurement time (horizontal, x-axis). The settings for the vertical
axis, regarding amplitude and scaling, are described here.
● Impact of the Vertical Axis Settings .......................................................................393
● Amplitude Settings ................................................................................................ 395
● Scaling the Y-Axis .................................................................................................399
● How to Optimize the Amplitude Display ................................................................401
6.4.1 Impact of the Vertical Axis Settings
Some background knowledge on the impact of the described settings is provided here
for a better understanding of the required configuration.
● Reference Level ....................................................................................................393
● RF Attenuation ...................................................................................................... 394
● Scaling .................................................................................................................. 395
6.4.1.1 Reference Level
The reference level value is the maximum value the AD converter can handle without
distortion of the measured value. Signal levels above this value will not be measured
correctly, which is indicated by the "IF OVLD" status display. The reference level
should correspond with the maximum expected RF input level.
When determining the expected input level, consider that the power from all input sig-
nals contribute to the total power. The reference level must be higher than the total
power from all signals.
Amplitude and Vertical Axis Configuration