Rohde & Schwarz R&S FSL3 - Page 227

Setting Traces – TRACE Key R&S FSL
1300.2519.12 4.42 E-11
In continuous sweep mode after the first statistics cycle, continuous averaging is performed.
The average trace n is calculated at each measurement point according to:
)(
1
)1(
1
)( nCurr
c
nAvg
c
c
nAvg +

= Equ. 4–2
with Avg = average trace; Curr = current trace
In single sweep mode, the same formula holds true if the Continue Single Sweep softkey is
pressed.
• sweep count = 0
In continuous sweep mode, a continuous average is calculated according to Equ. 4–3.
with c = 10:
)(
10
1
)1(
10
9
)( nCurrnAvgnAvg += Equ. 4–3
with Avg = average trace; Curr = current trace
Due to the weighting between the current trace and the average trace, past values 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.
• sweep count = 1
The current trace is displayed. No averaging is performed. This is a special case of Equ. 4–1 with
n = 0.
Detector overview
The measurement detector for the individual display modes can be selected directly by you or set
automatically by R&S FSL. The detector activated for the specific trace is identified in the respective
trace display field in form of an abbreviation (for details see detector list).
The detectors of the R&S FSL are implemented as pure digital devices. They collect signal power data
within each measured point during a sweep. The default number of sweep points is 501. The following
detectors are available:
Detector Indicator
Function
auto peak detector
(Auto Peak)
Ap determines the maximum and the minimum value within a
measurement point
peak detector
(Positive Peak)
Pk determines the maximum value within a measurement point
min peak detector
(Negative Peak)
Mi determines the minimum value within a measurement point
sample detector
(Sample)
Sa selects a random value within a measurement point
RMS detector (RMS)
Rm determines the root mean square power within a
measurement point
average detector
(Average)
Av determines the linear average power within a measurement
point
quasi peak detector
(Quasi Peak)
QP determines the quasipeak power within a measurement point
for EMI measurements (available from firmware version 1.10)