Agilent Technologies FieldFox N9912A - Adjacent Channel Power Ratio

100 N9912A FieldFox User’s Guide
Frequency Span
Occupied BW is calculated from power that is measured over the entire
displayed Frequency Span. The frequency span can be entered using arbitrary
frequencies or by using a Radio Standard in conjunction with channel numbers.
Learn how to select a Radio Standard and channels on page 72.
To change Frequency Span:
 Press Freq/Dist
 Then Freq Span
 Enter a value using the numeric keypad, ▲|▼ arrows, or the rotary knob.
 Press Enter
Power Percent
This setting specifies the percentage of total measured power to display between
the vertical posts. The measurement defaults to 99% of the occupied bandwidth
power. The remaining power (1% of default setting) is evenly distributed; .5% of
the power on the outside of each side of the vertical posts.
To change Power Percent:
 Press Meas Setup 4
 Then Power Percent
 Enter a value between 10 and 99.99 using the numeric keypad, ▲|▼ arrows,
or the rotary knob.
 Press Enter.
Other Occupied Bandwidth Settings
All relevant FieldFox settings are made automatically to ensure the highest
accuracy, such as ResBW, VideoBW, and sweep (SwpAcquisition) speed. These,
and all other SA Mode settings, can be changed manually in a Occupied
Bandwidth measurement.
 Learn about Measurement Preset on page 97.
 Learn about Averaging on page 97.
Adjacent Channel Power Ratio(ACPR)
ACPR measures the power of a carrier channel and the power in its adjacent
(offset) channels. The measurement results can help you determine whether the
carrier power is set correctly and whether the transmitter filter is working
properly.
You can measure the channel power in one, two, or three adjacent (offset)
channels on the low frequency and high frequency side of the center channel.
Limits can be used to quickly see if too much power is measured in the adjacent
channels.