Echo canceler far end energy discriminator
US4405840A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1981 |
| Grant date | Sep 20, 1983 |
| Priority date | — |
| Expiry date | Mar 5, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Energy in a received signal is distinguished as being whole band energy or partial band energy by comparing an average value of the received signal to a modified magnitude value of the received signal. When the modified magnitude value exceeds the average value, the received signal includes whole band energy, otherwise the received signal includes only partial band energy. This technique is employed in an echo canceler to enable updating an echo path estimate during intervals that the received signal includes whole band energy and to inhibit updating of the echo estimate being generated when the received signal includes only partial band energy
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.