Wavecom W40PC, Руководство пользователя

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Advanced Topics WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
and RQ are important additional classification aids in determining the mode under
examination.
In the case of ITA-5 (ASCII) systems only one data line is displayed as the ITA-5 alphabet has
no LTRS-FIGS shift.
Fast Scan / Full Scan
The software then proceeds with creating a list of the modes to check, which is displayed in the
”Modes to check” window. This list depends on the adjustment ”Fast Scan” or ”Full Scan”. In
”Fast Scan” mode, the list only contains the modes, which are known to use the detected baud
rate. In case of ”Full Scan” every mode is listed, which is suited to run the ”FSK Code Check”.
It is possible to change the detection mode between Fast Scan and Full Scan. You can
switch between the two modes by two different ways:
•
Menu Options
,
Scan Mode
•
Click into the mode field on the decoder status bar.
Fast Scan evaluates not all possible combinations. It makes a pre evaluation according to an
internal list, this safes time.
In Full Scan all possible combinations are evaluated.
VHF FSK CODE CHECK INDIRECT (W51PC, W40PC)
"FSK Code Check Indirect" is started in automatic mode by selecting the Code Check button
or from "
VHF/UHF-Modes/Analysis INDIRECT/FSK Code Check
".
The Analysis is started with the input, gain, translation frequency etc. that was used, last time
in a VHF INDIRECT mode. This selection is only available in the menu Preferences… the
"When selecting the toolbar "Analysis Buttons" start HF analysis mode" is not enabled. (See
Preferences…
on page 54)
As an additional help "FSK Code Check Indirect" also offers an option to start the analysis
manually after user entry of baud rate, shift and center frequency. The software will then start
the analysis using the pre-selected parameters.
”FSK Code Check Indirect” is a continuous process. If the baudrate, the center and the shift are
determined correctly, there is no need to restart the analysis, even in case of strong
disturbances during signal sampling. In such a case, the detection of a mode needs more time.
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.