Wavecom W40PC, Manual

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WAVECOM Decoders v6.15 W40PC, W41PC, W51PC Transmission Modes
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In addition to the time multiplexing of several channels (division channels), each division
channel may be further subdivided into sub-channels resulting in a multitude of possible modes
of operation. At present however no transmissions with sub-channel division are known.
Systems employing sub-channel division may be recognized by the rhythmic blinking of the
Error indication (system state) in the decoder status bar.
ARQ6-90 and ARQ6-98
Parameter Value
Frequency range HF
System SIMPLEX, ARQ System
Baudrate 200 Baud, variable 30-650 Baud
Modulation SSB or DIRECT-FSK
Receiver settings CW, LSB or USB
Signal source(s) AF, HF or IF
Alphabet Sitor
ARQ6-90 and ARQ6-98 operate at a speed of 200 Baud on the radio link.
ARQ6-90 and ARQ6-98 systems transmit 6 characters of 7 bits each in every data block
resulting in a total of 42 bits. The SITOR alphabet with a mark-space ratio of 3:4 is used.
Both systems operate on the ARQ principle. Using the ARQ method, a data block of 42 bits is
transmitted. The SITOR alphabet is used to protect the transmitted data. After each
transmission the direction of transmission is reversed and the remote station acknowledges
error-free data or requests a repetition of data received in error.
The two systems only differ in the duration of the request cycle interval.
A complete cycle for ARQ6-90 has a duration of 450 ms of which the data block is 210 ms an
interval is 230 ms.
A complete cycle for ARQ6-98 has a duration of 490 ms of which the data block is 210 ms an
interval is 280 ms.
ASCII
Parameter Value
Frequency range HF
System STANDARD, Out of sync Start-Stop System
Baudrate 50 - 1200 Baud
Modulation SSB or DIRECT-FSK
Receiver settings CW, LSB or USB
Signal source(s) AF, HF or IF
Alphabet ITA-5
For ASCII mode standard baudrates from 110 to 300 Baud are available. Non-standard
baudrates may be selected using the Baudrate menu item.
The ASCII code, which is adapted as the CCITT ITA-5 alphabet, is used in all kinds of data
transfer of information between computers or computer based equipment. The code consists of
a start bit, 7 or 8 data bits, one parity bit (optional) and 1 or 2 stop bits.
The parity bit allows error detection to be made. The number of “1”’s are counted. If an odd
number is found and parity has been defined as ODD, then the parity bit should be “1”,