BIRD SignalHawk SH-36S-RM-ASL, Руководство по эксплуатации

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Measurements
109
Occupied Bandwidth Measurement
Occupied Bandwidth measures the frequency band bandwidth that contains a specified
percentage of the total power of the signal.
Occupied Bandwidth measurement gives best results with single-peaked signals. Bandwidth can
be defined in two ways, % or dBc, 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.
Occupied Bandwidth Setup
For the best accuracy, set the center frequency so the main or carrier signal is centered on the
screen before taking measurements.
The Occupied Bandwidth Measurement can be turned on using the Start Menu or the Measure
Menu .
1. Click on the Measure Menu button ( 5 ). See Occupied Bandwidth Measurement Figure .
2. Click on Occupied BW: Menu Button.
3. If measurement is not already on, Click on Occupied BW: On/Off option ( 1 ) to turn on
measurement.
NOTE
Underlined option is the active option.
4. Click on Threshold Mode option ( 2 ) to select either % or dBc.