发明名称 |
Image communication system, and image communication apparatus and modem used in the system |
摘要 |
In an image communication system capable of performing communication at a plurality of transmission speeds, a transmission-side apparatus transmits a line condition check signal (a TCF signal of the CCITT facsimile recommendation T30, or the like) for determining a transmission speed prior to communication of image data. A reception-side apparatus determines an optimal transmission speed on the basis of a reception state of the line condition check signal (a square error accumulation value, an error count result, or the like in an equalizer of a reception-side modem), and informs the determined transmission speed or a fall-up or fall-down instruction of a transmission speed to a necessary step to the transmission-side apparatus. The optimal transmission speed according to a line condition can be set within a very short period of time.
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申请公布号 |
US5351134(A) |
申请公布日期 |
1994.09.27 |
申请号 |
US19920994471 |
申请日期 |
1992.12.21 |
申请人 |
CANON KABUSHIKI KAISHA |
发明人 |
YAGUCHI, TATSUYA;YOSHIDA, TAKEHIRO |
分类号 |
H04N1/333;(IPC1-7):H04N1/00 |
主分类号 |
H04N1/333 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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