Voice activity detector for controlling echo canceller

Details Voice activity detector for controlling echo canceller Voice activity detector for controlling echo canceller

1993-12-20

1995-07-18

Chin, Stephen

Telephonic communications

Echo cancellation or suppression

379407, 379410, 370 321, H04M 100, H04M 900, H04M 908, H04J 100

Patent

active

054349168

ABSTRACT:
In a voice activity detector for an echo canceller, a difference (a-b) is detected between a voltage at the receive path of a four-wire circuit of a hybrid transformer and a voltage at the transmit path of the four-wire circuit to produce a first difference signal, and an echo return loss (ERL) estimate is derived from the first difference signal. The first difference signal is compared with the ERL estimate to produce a first binary signal. A difference (b-c) is detected between the voltage at the transmit path and an output voltage of the echo canceller to produce a second difference signal, and an echo return loss enhancement (ERLE) estimate is derived from the second difference signal. The second difference signal is compared with the ERLE estimate to produce a second binary signal which forms together with the first binary signal one of a plurality of combinations of binary levels. The estimator of the echo canceller is enabled in response to a predetermined one of the combinations of binary levels and disabled in response to the other combinations.

REFERENCES:
patent: 3497641 (1970-02-01), Helder et al.
patent: 4469916 (1984-09-01), de Bergh et al.
patent: 4918727 (1990-04-01), Rohrs et al.
patent: 5343521 (1994-08-01), Jullien et al.
patent: 5353398 (1994-10-01), Sendyk et al.

Affiliated with

Also associated with

Rating

Voice activity detector for controlling echo canceller does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Voice activity detector for controlling echo canceller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Voice activity detector for controlling echo canceller will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2421673