| 摘要 |
PROBLEM TO BE SOLVED: To obtain a facsimile transmitter where a coding rate of a G3 facsimile signal coder in combination with a voice coder at a low bit rate can be enhanced. SOLUTION: When detecting a G3 facsimile signal, a changeover switch control circuit 5 of this facsimile transmitter generates a switch control signal e. A CLAD device 4 multiplexes voice signal coding output data and a G3 facsimile signal coding output data, assembles the multiplexed data into cells and transmits them to a transmission line. Upon the receipt of the switch control signal, a band control circuit 6 checks traffic of the transmission line and generates a rate change permission signal to a G3 facsimile signal coder 2 when the extension of the frequency band is available. Upon the receipt of the rate change permission signal, a coding rate control circuit 7 changes a coding rate of the G3 facsimile signal to generate a band extension request signal g. The band control circuit 6 receives the band extension request signal g to extend the transmission signal frequency band.
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