Anti-howling structure

Details Anti-howling structure Anti-howling structure

2011-08-02

2011-08-02

Jamal, Alexander (Department: 2614)

Telephonic communications

Echo cancellation or suppression

Disable or inhibit function

Reexamination Certificate

active

07991146

ABSTRACT:
A howling control structure for a full duplex communication system. The structure is implemented as part of an acoustic echo canceller having a conventional transversal adaptive filter. A second transversal adaptive filter, shorter than the conventional filter, that adapts even in the absence of speech in its reference signal, is provided. The short filter adapts quickly and provides enough echo cancellation to prevent howling from occurring, even if the echo path is changed significantly during silence periods.

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