Subband acoustic echo canceller
US5721772A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1996 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Oct 15, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/082
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a subband acoustic echo canceller, FG/BG filters are provided in M ones of N subbands into which the received signal is divided, and adaptive filters are provided in the other remaining subbands. In the respective FG/BG filters, during the detection of a non-double-talk state their transfer logic parts output state signals GD-j, GD-k, . . . and their adaptive operation control parts each apply an adaptation condition signal ADP to the adaptive filter in each of the above-mentioned other remaining subbands when a predetermined number or more of the FG/BG filters output the state signals GD-j, GD-k, . . . The adaptive filter updates the subband estimated echo path coefficient only when it is supplied with the signal ADP.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.