Title:
ECHO CANCELING METHOD AND DEVICE
Document Type and Number:
Japanese Patent JP3573241
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide an echo canceling method and a device by which an echo signal is sufficiently canceled without causing deterioration in speech quality depending on the quantity of a transmission delay.
SOLUTION: A filter coefficient of each of adaptive filters 44-1 to 4-N composed of a pseudo echo path of each frequency band is sequentially corrected to minimize a cancellation error of an echo signal and a tap length assignment circuit 51 decides a tap length indicating a number of the filter coefficient of each adaptive filter based on a sufficient echo required for a suppression quantity decided by a mean power level of an echo voice signal taking the masking effect with a speech voice into account and by an audible level for a human voice.
Inventors:
Sumiu Sakauchi
Shoji Makino
Yoichi Haneda
Junji Kojima
Shoji Makino
Yoichi Haneda
Junji Kojima
Application Number:
JP5954997A
Publication Date:
October 06, 2004
Filing Date:
March 13, 1997
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
H04R3/02; H03H17/02; H03H21/00; H04B3/20; H04M1/60; (IPC1-7): H03H21/00; H04B3/20; H04M1/60; H04R3/02
Domestic Patent References:
| JP9008709A | ||||
| JP64029094A | ||||
| JP633829A |
Other References:
阪内澄宇,牧野昭二,拡散通信システムにおける周波数帯域別所要エコー抑圧量の検討,日本音響学会平成8年度秋季研究発表会講演論文集-1-,日本,日本音響学会,1996年 9月25日,第547頁~第548頁
Attorney, Agent or Firm:
Hidekazu Miyoshi
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