Title:
ECHO CANCELLER
Document Type and Number:
Japanese Patent JP3680009
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To easily improve the rise responsiveness of an echo canceller by making the tap coefficient of an adaptive filter to be able to be converged in a short time with a small computing amount.
SOLUTION: This echo canceller is provided with a second adaptive filter 14c for learning, an adder 14d for learning, and first and second inverse filters 14e and 14f, in addition to a first adaptive filter 14a and an adder 14b, both of which are used for canceling acoustic echoes in transmitting voice signals. The inverse filters 14e and 14f generate white noise signals, from which the correlation between received digital voice signals and the correlation between the acoustic echoes are removed, based on an LPC parameter reproduced by means of a voice-decoding circuit 9, and the second adaptive filter 14c and adder 14d are caused to make learning based on the white noise signals. Then pseudo echoes, used for canceling the acoustic echoes, are generated by transferring the tap coefficient updated through the learning of the filter 14c and adder 14d to the first adaptive filter 14a.
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Inventors:
Yuji Okuda
Application Number:
JP2001224598A
Publication Date:
August 10, 2005
Filing Date:
August 11, 1994
Export Citation:
Assignee:
Toshiba Corporation
International Classes:
H03H21/00; H04B3/23; H04M1/60; (IPC1-7): H04B3/23; H04M1/60
Domestic Patent References:
| JP63248226A | ||||
| JP4022227A | ||||
| JP5083166A | ||||
| JP7066757A | ||||
| JP64002424A | ||||
| JP5145378A |
Attorney, Agent or Firm:
Takehiko Suzue
Sadao Muramatsu
Atsushi Tsuboi
Ryo Hashimoto
Satoshi Kono
Makoto Nakamura
Shoji Kawai
Sadao Muramatsu
Atsushi Tsuboi
Ryo Hashimoto
Satoshi Kono
Makoto Nakamura
Shoji Kawai