Systems and methods of echo and noise cancellation in voice communication
US9088336B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2013 |
| Grant date | Jul 21, 2015 |
| Priority date | — |
| Expiry date | Sep 4, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/082
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In an example, time and frequency domain speech enhancement is implemented on a platform having a programmable device, such a PC or a smartphone running an OS. Echo cancellation is done first in time domain to cancel a dominant portion of the echo. Residual echo is cancelled jointly with noise reduction during a subsequent frequency domain stage. The time domain block uses a dual band, shorter length Adaptive Filter for faster convergence. Non-linear residual echo is cancelled based on an echo estimate and an error signal from the adaptive filters. A controller locates regions that had residual echo suppressed and which do not have speech and injects comfort noise. The controller can be full-duplex and operate non-linearly. An AGC selectively amplifies the frequency bins, based on the Gain function used by the residual echo and noise canceller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.