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Common Analysis and Display Functions
R&S
®
FSW
486
User Manual 1173.9411.02 ─ 19
For n dB down markers, additional information is displayed, see
"Measuring Characteristic Bandwidths (n dB Down Marker)"
Marker information in marker table
In addition to the marker information displayed within the diagram area, a separate
marker table may be displayed beneath the diagram. This table provides the following
information for all active markers:
Type
Marker type: N (normal), D (delta), T (temporary, internal) and number
Ref
Reference marker for delta markers
Trc
Trace to which the marker is assigned
X-value
X-value of the marker
Y-value
Y-value of the marker
Function
Activated marker or measurement function
Function Result
Result of the active marker or measurement function
7.4.1.4
Searching for Signal Peaks
A common task in spectrum analysis is determining peak values, i.e. maximum or mini-
mum signal levels. The R&S
FSW provides various peak search functions and applica-
tions:
●
Setting a marker to a peak value once (Peak Search)
●
Searching for a peak value within a restricted search area (Search Limits)
●
Creating a marker table with all or a defined number of peak values for one sweep
(Marker Peak List)
●
Updating the marker position to the current peak value automatically after each
sweep (Auto Peak Search)
●
Creating a fixed reference marker at the current peak value of a trace (Peak
Search)
Peak search limits
The peak search can be restricted to a search area. The search area is defined by limit
lines which are also indicated in the diagram. In addition, a minimum value (threshold)
can be defined as a further search condition.
When is a peak a peak? - Peak excursion
During a peak search, for example when a marker peak table is displayed, noise val-
ues may be detected as a peak if the signal is very flat or does not contain many
peaks. Therefore, you can define a relative threshold ("Peak excursion"). The signal
level must increase by the threshold value before falling again before a peak is detec-
ted. To avoid identifying noise peaks as maxima or minima, enter a peak excursion
value that is higher than the difference between the highest and the lowest value mea-
sured for the displayed inherent noise.
Marker Usage