Echo canceller
US4868874A · kind A · utility
17Cited by
4References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1987 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Apr 16, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/238
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An echo canceller which cancels an echo by generating a replica of echo from the transmit data when the signal from the transmit line appears as an echo signal on the receive line, and subtracting the replica of echo from the echo signal in a circuit for connecting a transmit line and receive line to the full duplex transmission line through a hybrid circuit. The echo canceller for generating a replica of echo is composed of the first circuit which generates a replica of echo of limited length and a second circuit in which generates a replica of echo for eliminating the residual echo that is not cancelled by the first circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.