Spectrum Measurements
R&S
®
ESRP
247
User Manual 1175.7445.02 ─ 08
Working with Limit Lines in SEM Measurements
Using the R&S
ESRP, the spectrum emission mask is defined using limit lines. Limit
lines allow you to check the measured data against specified limit values. Generally, it
is possible to define limit lines for any measurement in Spectrum mode using the
[Lines] key. For SEM measurements, however, special limit lines are available via the
"Sweep List", and it is strongly recommended that you use only these limit line defini-
tions.
In the "Sweep List" you can define a limit line for each power class that varies its level
according to the specified frequency ranges. Distinguished limit lines
("_SEM_LINE_ABS<0...3>"/"_SEM_LINE_REL<0...3>") are automatically defined for
each power class according to the current "Sweep List" settings every time the settings
change.
The limit line defined for the current power class is indicated by a red line in the dis-
play, and the result of the limit check is indicated at the top of the diagram. Note that
only "Pass" or "Fail" is indicated; a "margin" function as for general limit lines is not
available.
The indicated limit line depends on the settings in the "Sweep List". Several types of
limit checks are possible:
Limit check type
Pass/fail criteria
Indicated limit line
Absolute
Absolute power levels may not
exceed limit line
Defined by the "Abs Limit Start"/ "Abs Limit
Stop" values for each range
Relative
Power deviations relative to the TX
channel power may not exceed limit
line
Defined by the "Rel Limit Start"/ "Rel Limit
Stop" values (relative to the center frequency)
for each range
Measurements