| 摘要 |
PROBLEM TO BE SOLVED: To reduce a circuit scale by having a small dynamic range of a tap coefficient within an echo replica generation part in an echo canceler. SOLUTION: An echo replica generation part 110 generates an echo replica 4 from a transmitted signal 3, and an echo replica range variation part 120 receives a set value 9 from an automatic gain control circuit and varies the echo replica 4 outputted from the echo replica generating part 110. An echo subtraction part 130 cancels an echo signal contained in a received signal 6 and an echo signal in signals coming from the counter side with a new echo replica 5 outputted by the echo replica range variation part 120. An echo residual variation part 140 receives an echo residual 7 outputted from the echo subtraction part 130 and the AGC set value 9 and varies the range of the echo residual for updating the tap coefficient of the echo replica generation part 10. COPYRIGHT: (C)2003,JPO
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