Wavecom W74PC V8.7.0 - Manual (Page 198)

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Transmission Modes WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0
The decoder uses an equalizer to demodulate the high-speed PSK signal. To visualize the power of the
equalizer, the user can turn on the dedicated phase plane in Options -> Show Phase Plane. The points
in yellow refer to data symbols before equalization, whereas the blue points refer to data symbols after
equalization.
MIL-188-110B (Appendix C), STANAG 4539
The MIL-STD-188-110B "Interoperability and Performance Standards for Data Modems", published on
27th April 2000 by the US Department of Defense (DoD) includes in its appendices different kinds of mo-
dem waveforms. The Appendix C defines the HF data modem waveforms and coding specifications for data
rates above 2400 bps, i.e., for data rates of 3200, 4800, 6400, 8000 and 9600 bps. Uncoded operation at
12800 bps is a DO (Design Objective). The single-tone waveforms specified use 8-PSK, 16-, 32- and 64-
QAM on a single carrier frequency (1800 Hz) as the modulation techniques. The waveform has a unique
symbol rate of 2400 Bd. Together with a constraint length 7, rate 1/2 convolutional code (FEC), punctured
to rate 3/4, the various effective user data rates (except 12800 bps) are realized. A linear interleaver is
used to redistribute the FEC coded user data bits of a certain block length ranging from 0.12 sec to 8.64
sec, thus producing a delay in the data transmission.
Parameter Value
Frequency range HF
Operation modes PSK, Broadcast/Simplex FEC
Modulation 8-PSK, 16-QAM, 32-QAM and 64-QAM
Symbol rate 2400.0 Bd
Center frequency 1800 Hz
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
This mode is equivalent to NATO STANAG 4539.
MIL-188-110B Appendix C single-tone waveform has the following characteristics: