Acoustic echo reduction circuit for a...

Details Acoustic echo reduction circuit for a... Acoustic echo reduction circuit for a...

2007-08-10

2011-11-29

Chang, Kent (Department: 2617)

Telecommunications

Transmitter and receiver at same station

Radiotelephone equipment detail

C455S569200, C379S388010, C379S406050, C379S406010, C379S387010, C348S611000, C348S607000

Reexamination Certificate

active

08068884

ABSTRACT:
A device comprising a circuit for picking up acoustic signals with the microphone; a circuit for playing back audio signals with an amplifier and a loudspeaker; an interface circuit for interfacing with a telephone network or a cell phone; and a circuit for digitally processing audio signals and reducing the acoustic echo that results from interaction of the loudspeaker with the microphone. The circuit for digitally processing audio signals comprises: an echo cancellation stage with an adaptive linear filter suitable for subtracting from the signal picked up by the microphone a reference signal that is derived from the signal received at the output from the interface; a gain control stage for suppressing the residual echo, and a stage for selectively reducing the background noise present in the signal received at the output from the echo suppression stage.

REFERENCES:
patent: 6442275 (2002-08-01), Diethorn
patent: 6970558 (2005-11-01), Schmidt
patent: 2002/0154761 (2002-10-01), McLaughlin et al.
patent: 2004/0052358 (2004-03-01), Lashley et al.
patent: 2005/0286714 (2005-12-01), Tokuda
patent: 0596623 (1994-05-01), None
patent: 60-102052 (1985-06-01), None
patent: 2-209027 (1990-08-01), None
patent: 96/26592 (1996-08-01), None
patent: 0025441 (2000-05-01), None

Affiliated with

Also associated with

Rating

Acoustic echo reduction circuit for a... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Acoustic echo reduction circuit for a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Acoustic echo reduction circuit for a... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-4311931