Title:
ECHO CANCELLER
Document Type and Number:
Japanese Patent JP2853455
Kind Code:
B2
Abstract:
PURPOSE: To obtain an echo canceller equipped with a digital interface having an excellent converging characteristic and an echo erasing capability, in a line in which a quantized noise or an over load noise generated on a PCM line or the like are present.
CONSTITUTION: This device is newly equipped with a subtracter 7 for a transmission output, subtracter 23 for a filter coefficient update, and non-linear quantization processor 24 which searches and outputs an optimal estimated echo whose difference from a transmitted input signal is the minimum based on the output of an echo estimating equipment 6 which prepares an estimated echo for an echo from an echo path. Then, the optimal estimated echo is subtracted from the transmitted input signal by the subtracter 7 for the transmission outputting use, transmitted to a far-end speaker as a residual echo, the estimated echo is subtracted from the transmitted input signal by the subtracter 23 for the filter coefficient update, inputted to the echo estimating equipment 6, and the filter coefficient of an adaptive filter is updated.
Inventors:
IIZUKA SHIGERU
HACHITSUKA YOTARO
HACHITSUKA YOTARO
Application Number:
JP14796392A
Publication Date:
February 03, 1999
Filing Date:
May 15, 1992
Export Citation:
Assignee:
KEI DEI DEI KK
International Classes:
H04B3/23; (IPC1-7): H04B3/23
Domestic Patent References:
| JP4213927A | ||||
| JP4286218A | ||||
| JP5129989A |
Other References:
菅谷史昭，飯塚茂，八塚陽太郎 著 “２つの疑似エコー推定回路を有するエコーキャンセラ”，１９９１年電子情報通信学会春季全国大会講演論文集，分冊３，（１９９１．３．１５）Ｐ．３−３１０
菅谷史昭，飯塚茂，八塚陽太郎 著 “ＰＣＭ回線の適用する２つの疑似エコー推定回路を有するエコーキャンセラ”，１９９１年電子情報通信学会秋季全国大会講演論文集，分冊３，（１９９１．８．１５）Ｐ．３−２４０
菅谷史昭，飯塚茂，八塚陽太郎 著 “ＰＣＭ回線の適用する２つの疑似エコー推定回路を有するエコーキャンセラ”，１９９１年電子情報通信学会秋季全国大会講演論文集，分冊３，（１９９１．８．１５）Ｐ．３−２４０
Attorney, Agent or Firm:
Keiichi Yamamoto