Keysight Technologies N9321C, Руководство пользователя

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Key Reference
Meas
Occupied BW
Occupied Bandwidth integrates the power of the displayed
spectrum. The power-bandwidth routine first computes all signal
power contained in the trace, then calculates the span containing
the power of the specified percentage. The percentage value
default is 99% of the occupied bandwidth power.
For 99% occupied power bandwidth, Markers are placed at the
frequencies on either side of 99% of the power. 1% of the power is
evenly distributed outside the markers. The difference between the
marker frequencies is the 99% power bandwidth.
This is the main menu of occupied bandwidth measurement
including all related parameters and measurement results.
The occupied bandwidth function also indicates the difference
between the center frequency and the center frequency of the
channel. This “
Transmit Freq Error
” is defined
as the difference between the (f
1
+ f
2
)/2 and the tuned center
frequency of the signal.
• Selecting a Method
Press
MEAS > OBW > Method
to toggle the occupied bandwidth
measurement mode between
percentage (%)
and
dBc
.
• Setting Percentage (%)
Press
{OBW > Method > Percent
to edit the percentage of signal
power used when determining the occupied bandwidth. Press
{%}
to set the percentage ranging from 10.00% to 99.99%.
NOTE
To get the correct measurement result, first set the center frequency,
reference level, and channel spacing.