R&S ESU Series Operating Manual page 228

R&S ESU
Measurement of Occupied Bandwidth
An important characteristics of a modulated signal is its occupied bandwidth. In a
radio communications system for instance the occupied bandwidth must be limited
to enable distortion-free transmission in adjacent channels. The occupied bandwidth
is defined as the bandwidth containing a defined percentage of the total transmitted
power. A percentage between 10% and 99.9% can be set on the R&S ESU.
OCCUPIED
OCCUP BW ON | OFF
BANDWIDTH
% POWER BANDWIDTH
CHANNEL BANDWIDTH
ADJUST REF LVL
ADJUST SETTINGS
The OCCUPIED BANDWIDTH softkey activates measurement of the occupied
bandwidth according to the current configuration and opens the submenu for config-
uring the measurement. The softkey is available only in frequency domain (span >
0) and is highlighted when the measurement is switched on.
In the spectrum display mode, this measurement determines the bandwidth that
contains a predefined percentage of the power of the displayed frequency range (%
POWER BANDWIDTH softkey). The occupied bandwidth is output in the marker dis-
play field and marked on the trace by temporary markers.
•
•
OCCUP BW The OCCUP BW ON/OFF softkey switches measurement of the occupied band-
ON | OFF width on or off.
Remote command:
% POWER The % POWER BANDWIDTH softkey opens the entry of the percentage of power
BANDWIDTH related to the total power in the displayed frequency range which defines the occu-
pied bandwidth (percentage of total power).
The valid range of values is 10% to 99.9%.
Remote command:
CHANNEL The CHANNEL BANDWIDTH softkey opens an input window for defining the chan-
BANDWIDTH nel bandwidth for the transmission channel. For measurements in line with a specific
transmission standard, the bandwidth specified by the standard for the transmission
channel must be entered. The default setting is 14 kHz.
The specified channel bandwidth is used for optimization of the test parameters of
the R&S ESU with ADJUST SETTINGS.
Remote command:
Operating Manual 1302.6163.12 - 03
The softkey is only available in the frequency domain (span > 0).
The measurement is performed on the trace with marker 1. In order to evaluate
another trace, marker 1 must be placed on another trace by means of SELECT
TRACE in the MARKER menu
CALC:MARK:FUNC:POW:SEL OBW
CALC:MARK:FUNC:POW:RES? OBW
CALC:MARK:FUNC:POW OFF
SENS:POW:BWID 99PCT
SENS:POW:ACH:BWID 14kHz
Instrument Functions
Analyzer Mode
4.197