G-TOR operates at a radio channel rate of 100, 200 or 300 Bd. The quality of the radio channel determines the actual adjusted baud rate.
|
Parameter |
Value |
|
Frequency range |
HF |
|
Operation modes |
Simplex ARQ |
|
Modulation |
FSK |
|
Symbol rate |
100, 200 and 300 Bd adaptive |
|
Receiver settings |
DATA, CW, LSB or USB |
|
Input format(s) |
AF, IF |
|
Additional Info |
ITA-5 with block coding |
By clicking the Auto button, the demodulator will automatically adjust to the actual shift and center frequency followed by phasing with automatic baud rate and signal polarity detection.
With some skill the actual baud rate of G-TOR may be easily recognized. Baud rates of 100, 200 and 300 Baud may be manually selected. If so phasing will be accelerated.
After synchronism with a G-TOR signal has been achieved, the software will ensure the baud rate adaptation as is the case in Auto mode. After the end of transmission the software will re-synchronize.
The cycle duration of G-TOR is always 2.4 s. The data frame has a length of 1.92 s, which leaves 0.16 s for acknowledgement from the remote station. At 300 Baud 69 data bytes are transferred, at 200 Baud 45 bytes and at 100 Baud 21 bytes. After the end of the data block a control byte and a 16 bit CRC sum are appended.
On the receiving side up to 3 incorrect bits may be corrected using a (24, 12) Golay code. In addition the data bits are interleaved (bit interleaving).
The complex G-TOR system is described in detail by the manufacturer KANTRONICS in a booklet ("G-TOR, The New Mode, Articles, Charts, Protocol", edited by Shelley Marcotte).
Two code tables are defined for this mode, Code Table 0 and Code Table 1, which may be selected from Options/Code Table.