New function, 1 high-speed transmission, 1 v.8/v.34 protocol – Canon FAX-L1000 User Manual

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FAX-L1000 Chapter 3: Technical Reference

3. NEW FUNCTION

3.1 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.

3.1.1 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

for

increasing the S/N (signal-to-noise) ratio and the probing technique

for measuring line

characteristics and optimizing 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

are available:

33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200,
4800, and 2400 bps

• The modulation speed (baud rate)

can be selected from among 2400, 3000, and 3200

symbols/sec (required) or 2743, 2800, and 3429 symbols/sec (option). The data
transmission speed can be set more finely than the previous modems.

NOTE

*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.