Rohde & Schwarz FSW-K40, Руководство пользователя

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Measurements and Result Displays
R&S
®
FSW-K40
14 User Manual 1173.9286.02 ─ 15
3 Measurements and Result Displays
Access :
The Phase Noise application measures the phase noise of a single sideband of a car-
rier.
It features several result displays. Result displays are different representations of the
measurement results. They may be diagrams that show the results in a graphic way or
tables that show the results in a numeric way.
In the default state of the application, only the graphical display of phase noise results
is active.
Phase Noise Diagram ................................................................................................... 14
Residual Noise .............................................................................................................. 15
Spot Noise .....................................................................................................................16
Spur List ........................................................................................................................ 17
Sweep Result List ......................................................................................................... 18
Spectrum Monitor ..........................................................................................................19
Frequency Drift ..............................................................................................................20
Frequency and Level Stability ....................................................................................... 21
Reference Measurement ...............................................................................................21
Phase Noise Diagram
The phase noise diagram shows the power level of the phase noise over a variable fre-
quency offset from the carrier frequency.
Measurement range
The unit of both axes in the diagram is fix. The x-axis always shows the offset frequen-
cies in relation to the carrier frequency on a logarithmic scale in Hz. It always has a
logarithmic scale to make sure of a equal representation of offsets near and far away
from the carrier. The range of offsets that the x-axis shows is variable and depends on
the measurement range you have defined and the scope of the x-axis that you have
set.
For more information on the measurement range see Chapter 4.3, "Measurement
Range" , on page 24.
If the measurement range you have set is necessary, but you need a better resolution
of the results, you can limit the displayed result by changing the x-axis scope. The
scope works like a zoom to get a better view of the trace at various points. It does not
start a new measurement or alter the current measurements results in any way.
The y-axis always shows the phase noise power level contained in a 1 Hz bandwidth in
relation to the level of the carrier. The unit for this information is dBc/Hz and is also fix.
Y-axis scale
The scale of the y-axis is variable. Usually it is best to use the automatic scaling that
the application provides, because it makes sure that the whole trace is always visible.
You can, however, also customize the range, the minimum and the maximum values
on the y-axis by changing the y-axis scale.