The Spectrum Application (RF Measurements)
R&S
®
FPL1000
260
User Manual 1178.3370.02 ─ 11
The results of the initial peak search are shown in the Marker Table (see
ter 6.2.14.2, "EMI Measurement Results"
Peak searches can be performed automatically or manually.
Automatic peak search
If enabled, the automatic peak search starts as soon as you select the EMI measure-
ment and one or more markers are active. During automatic peak search, the
R&S
FPL1000 looks for the strongest peaks in the frequency range you are measuring
and positions a marker on those peaks after each sweep. If a
limit line
is assigned to
the trace, the peak search is based on the level difference between the trace and the
limit line. For each active marker, a peak is searched. You can use up to 16 markers
simultaneously.
The largest peak is always assigned to the active marker with the lowest number; sub-
sequent peaks are assigned to the active markers in ascending order.
The R&S
FPL1000 allows you to distribute markers among several traces. If you do so,
the marker with the lowest number assigned to a particular trace is positioned on the
largest peak of the corresponding trace.
Manual peak search
If automatic peak search is off, you can set the markers to any frequency you need
more information about manually. You can change the marker position with the rotary
knob or the cursor s, or position it to a particular frequency with the number s.
Setting markers is the same as setting markers in other spectrum measurements. For
more information, see
Searching for peaks over several traces
You can search for peaks on six traces simultaneously with a different weighting detec-
tor for each trace.
In this case, the R&S
FPL1000 searches for peaks on all traces separately, if you have
assigned at least one marker to each trace.
A typical selection for EMI measurement is to use the peak and the average detector.
After initial measurement, search for peaks on the peak trace and the average trace
separately. Thus, you can consider the distribution of narrowband and wideband sour-
ces of interference.
Example:
●
In the initial measurement, determine the peak on one trace using the average
detector by assigning a marker to that trace. For the marker frequency, perform a
refined measurement using the CISPR or RMS average detector.
●
In the initial measurement, determine the peak on another trace using the peak
detector by assigning another marker to that trace. For this marker frequency, per-
form a refined measurement using the quasi-peak detector.
Measurements and Results
