High-Speed Transmission; V.8/V.34 Protocol - Canon MultiPASS C530 Service Manual

MultiPASS C530/C560 Chapter 2: Technical Reference
8. NEW FUNCTION

8.1 High-speed Transmission

The image transmission time is reduced drastically compared with the previous models by the V.34 modem
(maximum transmission speed 33600 bps) recommended by ITU-T.

8.1.1 V.8/V.34 protocol

a) Outline
• The V.8 protocol is used as the startup protocol to move to V.34. The V.8 protocol enables
connection with fax machines, data modem and equipment using existing V-series modems. The
V.34 modem contains a modem circuit based on the previous recommendation to connect with the
previous modems and has upper compatibility.
• The actual data transmission speed is improved entirely on average by speeding the modulation
method and utilizing new techniques, such as the pre-emphasis technique
(signal-to-noise) ratio and the probing technique
the modem operation according to the line condition.
• The V.8 protocol, V.34 pre-protocol and post-protocol use full-duplex transmission to speed the
processing.
• Fourteen image transmission speeds
33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200, 4800, and
2400 bps
• The modulation speed (baud rate)
(required) or 2743, 2800, and 3429 symbols/sec (option). The data transmission speed can be set
more finely than the previous modems.
NOTE
*3
are available:
*4
can be selected from among 2400, 3000, and 3200 symbols/sec
*1 The output level of a high-frequency zone with comparatively high noise is raised,
and then the transmission signal is sent.
*2 A tone signal known as a probing signal (L1 and L2) is output, and the receiving
side measures the characteristics of the line.
*3 The data signaling rate is recorded in the ITU-T standards manual. Image
transmission speed means the same as data signaling rate.
*4 The symbol rate is recorded in the ITU-T standards manual. Symbol rate means the
same as moderation speed and baud rate.
2743 symbol/sec cannot be used with this fax.
*2
for measuring line characteristics and optimizing
2-36
*1
for increasing the S/N