Spectrum Measurements
R&S
®
ESR
253
User Manual 1175.7068.02 ─ 12
New: OBW now also possible within defined search limits - multi-carrier OBW
measurement in one sweep
The occupied bandwidth of the signal can be determined within defined search limits
instead of for the entire signal. Thus, only a single sweep is required to determine the
OBW for a multi-carrier signal. To do so, search limits are defined for an individual car-
rier and the OBW measurement is restricted to the frequency range contained within
those limits. Then the search limits are adapted for the next carrier and the OBW is
automatically re-calculated for the new range.
The OBW measurement uses the same search limits as defined for marker search
(see
on page 206). However, only the left and right limits are consid-
ered.
To ensure correct power measurement, especially for noise signals, and to obtain the
correct occupied bandwidth, the following prerequisites and settings are necessary:
●
Only the signal to be measured is displayed on the screen. An additional signal
would falsify the measurement.
●
RBW << occupied bandwidth
(approx. 1/20 of occupied bandwidth, for voice communication type 300 Hz or 1
kHz)
●
VBW ≥ 3 x RBW
●
RMS detector
●
Span ≥ 2 to 3 x occupied bandwidth
Some of the measurement specifications (e.g. PDC, RCR STD-27B) require measure-
ment of the occupied bandwidth using a peak detector. The detector setting of the
R&S
ESR has to be changed accordingly then.
Measurements