Wavecom W-CLOUD, Руководство пользователя

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WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V9.1.0 Analysis Tools
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FFT (HF, SUB, DIR and SAT)
FFT Type Start Frequency End Freqeuncy
FFT HF Offset Frequency Bandwidth
FFT SUB Offset Frequency Bandwidth
FFT DIR Offset Frequency – Bandwidth/2 Offset Fre Bandwidth/2
FFT SAT Offset Frequency – Bandwidth/2 Offset Fre Bandwidth/2
Tuning FFT or Sonagram
In some modes a Tuning FFT or Sonagram is available. The FFT or Sonagram can be used to set the
center frequency, shift, and passband filter.
Tuning FSK Signals
Mark and Space are selected with the right and left cursor. The precision of the center frequency is very
important and directly influences the performance of the decoder .
After every change, the center frequency and shift are automatically updated.
Automatic tuning is also available. It works perfectly as long as there is only one input signal present in
the spectrum. To apply a filter, see “
Passband Filter Support ” on page 78.
Options can be set using the right mouse button or the context menu (see “ FFT/Sonagram Context Menu ”
on page 72). It is possible to remove the tuning FFT or Sonagram in the View Menu .
Tuning MFSK Signals
The highest and lowest tone of the signal is selected with the right and left cursor. The precision of the
center frequency is very important and directly influences the performance of the decoder.
After every change, the center frequency and shift are automatically updated.
Another tuning cursor group with 8 (green) cursors helps to measure the center, bandwidth and the dis-
tance between multiple carriers in a more convenient way. The 8 cursors can be moved freely. This fea-
ture is helpful when measuring signals with non-equal carrier distance (as CHINESE 4+4 signal).