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Analysis Tools
WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V9.1.0
Waterfall (HF, SUB, DIR and SAT)
FFT Type
Start Frequency
End Freqeuncy
Waterfall HF
Offset Frequency
Bandwidth
Waterfall SUB
Offset Frequency
Bandwidth
Waterfall DIR
Offset Frequency – Bandwidth/2
Offset Fre Bandwidth/2
Waterfall SAT
Offset Frequency – Bandwidth/2
Offset Fre Bandwidth/2
Sonagram
A second widespread method for FFT display is the real-time sonagram, which displays the amplitude and
frequency values produced by the FFT over time. In the sonagram, the signal amplitude is displayed by
colour, with different colours representing different amplitudes. Sometimes this display is also called
“Spectrogram”.
This amplitude related spectrum analysis mode offers many hints to the distribution of a signal spectrum.
The operation is numerically identical to the real-time waterfall analysis, and is simply a different method
of visualisation.
Options can be set using the right mouse button or the context menu (see “
on page 72). It is possible to remove the tuning FFT or Sonagram in the
View Menu
.
Making measurements
With the four cursors it is possible to make measurements in the frequency and time domain. To enable
the time cursors, click into the sonagram to freeze the screen. Then click with the right mouse button to
get the menu to set the time cursors.
T1
Add first cursor to the actual mouse position
T2
Add second cursor to the actual mouse position
Move Move T1 cursor and T2 cursor simultaneously
It is also possible to drag the cursor to a new location. If the cursor line gets in the upper our lower part of
the window, then the window will scroll automatically.
