Bird Technologies SH-36S-RM-Manual - Manual (Page 69)

Measurements
53
Occupied Bandwidth Measurement
Occupied Bandwidth measures the frequency band bandwidth that
contains a specified percentage of the total power of the signal.
It gives best results with single-peaked signals. Bandwidth can be
defined in two ways. Both give measurement results in Hz units.
Threshold Modes
%
The calculated occupied bandwidth represents the user specified percent
of the total power of the displayed span. Best for Watts power units.
dBc
The bandwidth is calculated by finding the frequencies above and below
the center or carrier frequency that is the user specified dB below the
carrier level. This method is best for measuring dBm power units.
Setting Occupied Bandwidth
Note:
For the best accuracy, set the center frequency so the
main or carrier signal is centered on the screen before taking
measurements.
1. Select either % or dBc under Threshold Mode.
2. Do one of the following:
z If the % Threshold has been selected, go the % soft key
and set the desired threshold via either the mouse scroll wheel
or keyboard.
z If the dBc Threshold has been selected, go the dBc and set the
desired threshold via either the mouse scroll wheel or keyboard.
Note:
The threshold and the measured bandwidth will be
displayed in the “measurement settings” area at the bottom of
the display. Markers 1 and 2 will be turned on, and placed at
the band edges.
Figure 37 Example, Occupied Bandwidth
Measurement
Settings