Anti-howling structure
US7991146B2 · kind B2 · utility
4Cited by
5References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 15, 2005 |
| Grant date | Aug 2, 2011 |
| Priority date | — |
| Expiry date | Jan 2, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/082
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.