(4)Training
The training is performed in the binary procedure to surely transmit the image signals.
•Training signal
The training signal is transmitted following the DCS signal at the modem speed specified by the DCS signal. Responding to this training signal, the receiving side adjusts the
•Format of the training signal - 14.4 Kbps, 12 Kbps
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| Alternation | Equalizer |
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| adjustment | information | Scrambled binary data “1” |
| TCF | ||
| of ABAB |
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| pattern | sequence |
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| 106 msec | 1240 msec | 27 msec | 20 msec |
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| 1393 msec |
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-9600 bps, 7200 bps
Segment 1 Segment 2 / Segment 3 | Segment 4 |
V.29
No signal | Repeating | |
signal | ||
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20 msec | 53 msec+160 msec | |
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| 253 msec |
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Scrambled data “1” | TCF |
(Hexa or octal)
20 msec
-4800 bps, 2400 bps
| Segment 1Segment 2 Segment 3 | Segment 4 | Segment 5 |
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| Non- |
| Continuous | 0° to 180° |
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| 180° phase |
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V.27ter | modulated | No signal | Scrambled data “1” | TCF | |||
inversion | |||||||
| carrier |
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| (Binary) | (Binary) | (Hexa or octal) |
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4,800 bps: 923 msec,
2,400 bps: 1158 msec
•TCF signal
An error may occur in the image data if the training is not performed correctly. The transmit- ting side sends a TCF signal and checks if any error occurs in image data before the image data communication to follow. When the receiving side detects an error in the TCF signal, it transmits an FTT signal to the transmitting side to request the retraining. When there is no error, the receiving side transmits a CFR signal.
The TCF signal transmits all zeros for 1.5 seconds at the same modem speed as that for the training signal.
© 2003 - 2008 TOSHIBA TEC CORPORATION All rights reserved | |
DIALING/COMMUNICATION CONTROL |
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3 - 12
04/06
