Echo canceller

Details Echo canceller Echo canceller

1997-03-25

1999-09-28

Matar, Ahmad F.

Telephonic communications

Subscriber line or transmission line interface

Network interface device

379411, 379406, H04M 100

Patent

active

059600772

ABSTRACT:
A counter increments a count value every given time period. An adaptive operation control unit selects channels in which adaptive operations are done from all the channels in obedience to the count value to output produced selection signals to AND circuits. Double-talk detection circuits judge the presence/absence of a double-talk state and output detection signals to the AND circuits. The AND circuits operate logical AND of the selection signals and the detection signals and output the logical AND results as control signals to filter coefficient updating circuits. The filter coefficient updating circuits update or do not update filter coefficients stored in FIR filter units according to the control signals. The FIR filter units produce echo replicas by calculating convolutions of the filter coefficients and the receive signals. Subtractors subtract the echo replicas from transmission signals to output residual signals.

REFERENCES:
patent: 3894200 (1975-07-01), Campenella et al.
patent: 4894820 (1990-01-01), Miyamoto et al.
patent: 4918727 (1990-04-01), Bohrs et al.
patent: 5371789 (1994-12-01), Hirano
patent: 5396554 (1995-03-01), Hirano et al.
patent: 5483594 (1996-01-01), Prado et al.
patent: 5513265 (1996-04-01), Hirano

Affiliated with

Also associated with

Rating

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 Echo canceller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Echo canceller will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-712730