Keysight N9913B, Руководство пользователя

Страница: 217 / 896

Keysight N9938-90006 User’s Guide 217
SA (Spectrum Analyzer) Mode (Option 233–Mixed Analyzers)
Channel Measurements
Old Data Indicator (*)
In SA mode, when the current trace does not exactly match the annotation that
is on the screen, an asterisk is displayed in the upper-right corner of the screen
graticule area. This would occur, for example, when the Res BW setting is
changed while in sweep Hold mode. The annotation is changed immediately,
but the trace is not updated until the next sweep occurs. Therefore, the current
data trace does not match the screen annotation. See the asterisk in Figure
9-1 on page 147 .
Channel Measurements
The following Channel Measurements are offered in SA Mode:
Channel Power
“Channel Power (CHP)” on page 218
Occupied Bandwidth “Occupied Bandwidth” on page 220
Adjacent Channel Power Ratio “Adjacent Channel Power Ratio (ACPR)”
on page 222
Radio Standards and Channel Measurements
To tune the frequency range of any of the Channel Measurements using
channels instead of frequency, first select a Radio Standard, then select Units =
CHAN. Learn how to select a Radio Standard and channels in “How to select a
Radio Standard” on page 154 .
When you first select a Radio Standard, then select a Channel Measurement:
— With Units = FREQ selected, the center frequency and span will ALWAYS
change to the full frequency range of that standard (Uplink and Downlink)
to allow for a quick scan of energy. The X-axis annotation indicates the
frequency range.
— With Units = CHAN selected, the FieldFox chooses either the uplink or
downlink band, and displays that range of frequencies. You can then tune
within that Standard using Start CHAN, Stop CHAN, or Center CHAN. The
X-axis annotation indicates the frequency range.
When you first select a Channel Measurement , then select a Radio Standard ,
the BW, Offset, RRC, Integration BW, and Span settings are changed to those
of the standard. In addition, Res BW can also change when set to
‘Auto(couple)’. However, center frequency is NOT changed unless you first
select Units = CHAN.
Measurement Preset
Measurement Preset allows you to easily reset any of the channel
measurements to its default settings. The Center Frequency, Preamp ON|OFF,
RF Attenuation, Markers, Limits, and Radio Standard settings are NOT reset.