Wavecom W61PC V7.5.0 - Manual (Page 114)

104  Transmission Modes WAVECOM Decoder W61PC/LAN Manual V7.5
Transmission Modes
ACARS
Aircraft Communications Addressing and Reporting System (ACARS) is a carrier sensing, multiple access
packet radio system for aircraft communications. ACARS operates in the VHF band, mainly around 130
MHz, using 2400 bps NRZI coded coherent audio frequency MSK (Minimum Shift Keying - a particular form
of FSK) on AM to make use of standard aircraft AM communications equipment.
Parameter Value
Frequency range VHF
Operation modes CSMA/CD packet ARQ system
Modulation AM, SUB FSK
Symbol rate 2400 Bd
Center frequency 1800 Hz
Shift 1200 Hz
Receiver settings AM, BW = 3 kHz
Input format(s) AF, IF
Additional Info ITA-5 with parity and block coding
Frequencies Europe: 131.725, 131.525, 131.825 MHz
Frequencies USA: 131.550, 130.025, 129.125, 131.475, 130.450,
131.125, 136.700, 136.750, 136.800 MHz
Frequency Japan: 131.450 MHz
To receive ACARS an omni-directional 108-136 MHz antenna, a VHF AM receiver (scanner) with 13 kHz
channel bandwidth and a corresponding AF output is necessary. As the ACARS packets are very short, turn
the squelch of the receiver OFF.
Speed selection is not available for ACARS as only one speed is in use (2400 Baud)...