Method and apparatus for echo canceler disablement
US5014307A · kind A · utility
11Cited by
2References
36Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1989 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Nov 14, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An echo canceler is disabled by sending two signals to it or in the alternate, by sending a single signal. The two signals are bit shifted replicas of each other. The nature of the sequence of the bits within the signals assures that one of the two signals or in the alternate case, a single signal will disable the echo canceler. All of these signals are not necessarily comprised solely of tone at a predetermined frequency; rather they may merely have sufficient energy at a disabling frequency and sufficient signal noise ratio to disable the echo cancelers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.