Wavecom W40PC, Руководство пользователя

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Advanced Topics WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
Because these kind of signals are not sent continuously, there is a need for a noise gate. The
status of it is displayed in the status bar. The noise gate examines the input signal and tries to
find out, if a valid signal is available which can be processed or if the input consists only of
noise.
After starting the "FSK Code Check Direct" the shift and the baud rate are determined. These
values are displayed in the appropriate fields after the measurement has taken place.
The software then proceeds with creating a list of the modes to check, which is displayed in the
”Modes to check” window.
The incoming bit stream is now tested continuously against the pre-selected modes.
The name of each identified system is displayed in the ”Detected modes” window. An
identified system may be
started immediately by double-clicking the system in the
”
Detected modes
” window.
The
Hits-Checks
will show you how often during checking a mode was successful. If you
see multiple modes on the screen, then this will give you an indication which mode you have
to try.
If a mode is uniquely identified, the software will switch to the identified mode and decoding
is initiated. If two or more different systems are identified an automatic switch to a mode will
not take place.
PSK SYMBOL RATE and PSK PHASE PLANE
The Phase Analysis tool is used for analyzing the characteristics of phase modulated signals,
and to a limited extent, M-ary PAM (Phase-Amplitude-Modulation) signals.
The Phase Analysis tool contains three components:
•
Asynchronous mode phase plane
•
Synchronous mode phase plane