Wavecom W61PC V7.5.0 - Manual (Page 94)

84  Analysis Tools WAVECOM Decoder W61PC/LAN Manual V7.5
MIL-STANAG Code Check
The MIL/STANAG code check analysis tool is used to determine whether a signal is one of the following
MIL/STANAG and related transmission modes:
 HF-ACARS
 MIL-188-110A
 MIL-188-110B
 MIL-188-141B
 STANAG-4285
 STANAG-4529
STANAG-4415 is a sub-mode of MIL-188-110A and is detected as this mode. STANAG-4481 is a sub-mode
of STANAG-4285 and is detected as this mode.
This analysis feature can be started from the HF-Modes | Analysis | MIL-STANAG Code Check menu,
from the Analysis Selector.
The center frequency can be set by the user. The default value for the code check is 1800 Hz, as shown in
the user interface. The center frequency of HF-ACARS (1440 Hz) can be selected from a list. After the cen-
ter frequency is set, the code check searches for the mode within a range of ± 100 Hz of the center fre-
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.