Echo cancellers for sparse channels
US7471788B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 2002 |
| Grant date | Dec 30, 2008 |
| Priority date | — |
| Expiry date | Jul 7, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention is an echo canceller for sparse channels in an echo channel. The echo channel receives a far-end input and a near-end input. An enable generator asserts a sparse update enable in response to detecting at least one of the double talk condition and an impulse response change. A main weight updater transfers shadow weights of the shadow filter to N sets of sparse weights in N sparse filters of the main filter according to the sparse update enable. A sparse main filter filters the far-end input non-adaptively to generate a main output. A long shadow filter filters the far-end input adaptively to generate a shadow output and to estimate delays of peaks of the sparse weights in the main filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.