Common Analysis and Display Functions
R&S
®
FSVA3000/ R&S
®
FSV3000
490
User Manual 1178.8520.02 ─ 01
If you change any parameters that affect the scaling of the diagram axes, the
R&S
FSV/A automatically adapts the trace data to the changed display range. This
allows you to zoom into the diagram after the measurement to show details of the
trace.
How Many Traces are Averaged - Sweep Count + Sweep Mode
In "Average" trace mode, the sweep count and sweep mode determine how many
traces are averaged. The more traces are averaged, the smoother the trace is likely to
become.
The algorithm for averaging traces depends on the sweep mode and sweep count.
●
sweep count = 0
(default)
–
In
"Continuous"
sweep mode, a continuous average is calculated for 10
sweeps, according to the following formula:
10
*
9
MeasValue
Trace
Trace
old
Figure 9-11: Equation 1
Due to the weighting between the current trace and the average trace, past val-
ues have practically no influence on the displayed trace after about ten
sweeps. With this setting, signal noise is effectively reduced without need for
restarting the averaging process after a change of the signal.
–
In
"Single"
sweep mode, the current trace is averaged with the previously
stored averaged trace. No averaging is carried out for the first sweep but the
measured value is stored in the trace memory. The next time a sweep is per-
formed, the trace average is calculated according to the following formula:
2
MeasValue
Trace
Trace
old
The averaged trace is then stored in the trace memory.
●
sweep count = 1
The currently measured trace is displayed and stored in the trace memory. No
averaging is performed.
●
sweep count > 1
For both
"Single"
sweep mode and
"Continuous"
sweep mode, averaging takes
place over the selected number of sweeps. In this case the displayed trace is
determined during averaging according to the following formula:
1
1
)
(
1
n
i
n
i
n
MeasValue
T
n
Trace
Figure 9-12: Equation 2
Where n is the number of the current sweep (n = 2 ... Sweep Count).
No averaging is carried out for the first sweep but the measured value is stored in
the trace memory. With increasing n, the displayed trace is increasingly smoothed
since there are more individual sweeps for averaging.
Trace Configuration
