Title:
DOUBLE-TALK DETECTION DEVICE, ECHO CANCELLER USING DOUBLE-TALK DETECTION DEVICE AND ECHO SUPPRESSOR USING DOUBLE-TALK DETECTION DEVICE
Document Type and Number:
WIPO Patent Application WO/2000/051262
Kind Code:
A1
Abstract:
A first false echo signal which approximates an echo of a receiving signal overlapping a transmitting signal is produced from a past delayed receiving signal according to a filter factor, and a first residual signal is produced from the first false echo signal and a delayed transmitting signal. A filter factor is updated so as to reduce the first residual signal. When a single-talk condition based on the voice of a far-end speaker for a receiving signal migrates to a double-talk condition based on an addition of a voice of a near-end speaker to a transmitting signal, a filter factor deteriorates. A second false echo signal is produced from a receiving signal currently received according to an updated filter factor. Since there exists a time-wise deviation between a signal related to filter factor updating and a signal related to the generation of the second false echo signal, a deterioration component is indicated in a delayed second residual signal produced from the second false echo signal to enable the detection of a double-talk condition according to the difference between the delayed second residual signal and the first residual signal.
Inventors:
TASAKI HIROHISA (JP)
MATSUOKA BUNKEI (JP)
KAJIYAMA IKUO (JP)
TAKAHASHI SHINYA (JP)
MATSUOKA BUNKEI (JP)
KAJIYAMA IKUO (JP)
TAKAHASHI SHINYA (JP)
Application Number:
PCT/JP2000/001068
Publication Date:
August 31, 2000
Filing Date:
February 24, 2000
Export Citation:
Assignee:
MITSUBISHI ELECTRIC CORP (JP)
TASAKI HIROHISA (JP)
MATSUOKA BUNKEI (JP)
KAJIYAMA IKUO (JP)
TAKAHASHI SHINYA (JP)
TASAKI HIROHISA (JP)
MATSUOKA BUNKEI (JP)
KAJIYAMA IKUO (JP)
TAKAHASHI SHINYA (JP)
International Classes:
H04B3/20; H04B3/23; H04M1/60; (IPC1-7): H04B3/04; H04M1/60; H04M9/08
Foreign References:
| EP0667700A2 | 1995-08-16 | |||
| JPS62176338A | 1987-08-03 | |||
| EP0667700A2 | 1995-08-16 | |||
| JPS62176338A | 1987-08-03 |
Other References:
KAZUO OCHIAI ET AL.: "Echo Canceler with Two Echo Path Models", IEEE TRANSACTIONS ON COMMUNICATIONS,, vol. COM-25, no. 6, June 1977 (1977-06-01), pages 589 - 595, XP002927500
K. OCHIAI ET AL.: "Echo Canceler with Two Echo Path Models", IEEE TRANSACTIONS ON COMMUNICATIONS, vol. COM-25, no. 6, June 1977 (1977-06-01), pages 589 - 595
See also references of EP 1071225A4
K. OCHIAI ET AL.: "Echo Canceler with Two Echo Path Models", IEEE TRANSACTIONS ON COMMUNICATIONS, vol. COM-25, no. 6, June 1977 (1977-06-01), pages 589 - 595
See also references of EP 1071225A4
Attorney, Agent or Firm:
Tazawa, Hiroaki (Kasumigaseki 3-chome Chiyoda-ku Tokyo, Kasumigaseki 3-chome Chiyoda-ku Tokyo, JP)
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