Wavecom W74PC V8.7.0 - Manual (Page 107)

WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0 Analysis Tools
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quency. Although HF-ACARS may have a center frequency of 1440 Hz, it can also be detected when the
code check is set with center 1800 Hz.
Apart from HF-ACARS, which has a baud rate of 1800, all other MIL and STANAG modes operate at 2400
baud. However, the code check can automatically determine modes with different baud rates.
After the code check has determined a mode, the mode name is displayed in the text window. The confi-
dence parameter shows how good the match is, the highest possible value being 100%. When confidence
is greater than 90%, the code check automatically switches to the corresponding mode decoder using the
corrected center frequency.
MFSK Analysis
The MFSK analysis for the HF signal range employs a graphical display in two dimensions, frequency (y-
axis) and time (x-axis). Both values may be preset. This tool was originally developed for the analysis of
analogue tone call systems, but is equally suitable for evaluation of FSK and MFSK systems. In particular
the frequency and element duration is well displayed.
After starting MFSK Analysis the detected frequency values are displayed as pixels.
A monitored MFSK signal is easily recognized as stable lines. To stop the display from scrolling horizontal-
ly, click on the display. Measurement cursors for both the time axis and the frequency axis appear. The
display may be scrolled backwards, with a maximum range of 15 seconds when tracking rate is set to 1
ms, and 225 seconds when the tracking rate is set to 15ms. The scroll-back range for all tracking rate set-
tings in between varies accordingly.