Wavecom W-SPECTRA (Automatic Monitoring System) V1.1.0 - Manual (Page 124)

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Transmission Modes WAVECOM Monitoring System W-SPECTRA, W-SPEED Manual V1.1.0
Parameter Value
Frequency range HF
Operation modes Broadcast /Simplex FEC
Modulation FSK
Symbol rate 100.05 Bd, variable 30-650 Bd
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
Additional Info ITA-2 with 10 Bit redundancy
HNG-FEC operates at a symbol rate of 100.05 Baud on the radio link.
HNG-FEC employs bit spreading (interleaving) with a distance of 64 bits, each new character starting at
intervals of 15 bits. The software synchronizes to traffic as well as idle bit patterns. The idle binary bit pat-
tern is given by 110 100 110 010 011.
Transmission reliability for HNG-FEC is good with the code spread offering additional immunity against
burst errors.
HNG-FEC is started by clicking the Auto button or by selecting a Baudrate in the Demodulator menu.
By toggling the ECC item in the Options menu error correction may be enabled or disabled.
ICAO SELCAL
ICAO selective calling was initially defined in 1985 using twelve tones (Tones "A" to "M", but without tone
"I"). In 1994 the ICAO calling system, also known as ANNEX10, was extended with the additional tones
"P", "Q", "R" and "S" and now operates with 16 tones.
Parameter Value
Frequency range HF
Operation modes Analogue Selcal
Symbol rate 1000 ms
Modulation USB
Receiver settings USB
Input format(s) AF, IF
The allocation of selective call addresses is exclusively managed by Aeronautical Radio, Inc. ARINC (ICAO
Designator Selcal Registry).
Each address consists of two pairs of tones, e.g., "AB-CD". Both pairs have a duration of 1,000 ms. Be-
tween each pair an interval of 200 ms is inserted. ICAO Selcal is used on all frequency bands (HF and
VHF/UHF).
ICAO Selcal Tone Allocation
Designation Frequency (Hz) Designation Frequency (Hz)
RED "A" 312.6 RED "J" 716.1
RED "B" 346.7 RED "K" 794.3
RED "C" 384.6 RED "L" 881.0
RED "D" 426.6 RED "M" 977.2
RED "E" 473.2 RED "P" 1083.9
RED "F" 524.8 RED "Q" 1202.3
RED "G" 582.1 RED "R" 1333.5