Title:
VOLUME CONTROL FOR A COMMUNICATIONS DEVICE INCLUDING AN ECHO CANCELLER
Document Type and Number:
WIPO Patent Application WO2000070853
Kind Code:
A3
Abstract:
In handsfree communications devices including a linear echo or noise canceler, both analog and digital gain factors are adjusted in response to user volume control inputs, the analog gain factor being frozen during active communications (e.g., during telephone calls). By providing dual user controls, one of which is disabled when a call is in progress, embodiments of the invention provide the wide dynamic range required in most handsfree applications without degrading performance of the linear echo canceler.
Inventors:
ROMESBURG ERIC DOUGLAS
MAKOVICKA THOMAS JOHN
MAKOVICKA THOMAS JOHN
Application Number:
PCT/US2000/006716
Publication Date:
July 12, 2001
Filing Date:
May 12, 2000
Export Citation:
Assignee:
ERICSSON INC (US)
International Classes:
H04M9/08; (IPC1-7): H04M9/08
Foreign References:
| EP0999689A1 | 2000-05-10 | |||
| EP0515242A1 | 1992-11-25 |
Other References:
KUO S M ET AL: "ACOUSTIC NOISE AND ECHO CANCELLATION MICROPHONE SYSTEM FOR VIDEOCONFERENCING", IEEE TRANSACTIONS ON CONSUMER ELECTRONICS,US,IEEE INC. NEW YORK, vol. 41, no. 4, 1 November 1995 (1995-11-01), pages 1150 - 1158, XP000553493, ISSN: 0098-3063
MAKINO S ; KANEDA Y: "Acoustic echo canceller algorithm based on the variation characteristics of a room impulse response", ICASSP 90. 1990 INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (CAT. NO.90CH2847-2), vol. 2, 3 April 1990 (1990-04-03) - 6 April 1990 (1990-04-06), ALBUQUERQUE, NM, USA, pages 1133 - 1136, XP002157125
BERSHAD N J ET AL: "Saturation effects in LMS adaptive echo cancellation for binary data", IEEE TRANSACTIONS ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING,US,IEEE INC. NEW YORK, vol. 38, no. 10, 10 October 1990 (1990-10-10), pages 1687 - 1696, XP002122020
MAKINO S ; KANEDA Y: "Acoustic echo canceller algorithm based on the variation characteristics of a room impulse response", ICASSP 90. 1990 INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (CAT. NO.90CH2847-2), vol. 2, 3 April 1990 (1990-04-03) - 6 April 1990 (1990-04-06), ALBUQUERQUE, NM, USA, pages 1133 - 1136, XP002157125
BERSHAD N J ET AL: "Saturation effects in LMS adaptive echo cancellation for binary data", IEEE TRANSACTIONS ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING,US,IEEE INC. NEW YORK, vol. 38, no. 10, 10 October 1990 (1990-10-10), pages 1687 - 1696, XP002122020
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