Speakerphone linear comparator
US4492824A · kind A · utility
3Cited by
6References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 11, 1983 |
| Grant date | Jan 8, 1985 |
| Priority date | — |
| Expiry date | Aug 11, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/10
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
There is disclosed a precision linear comparator for a speakerphone circuit having two rectifying constant voltage nodes for separately summing two groups of signals derived from a speakerphone transmit channel and receive channel and supplying at an output terminal a signal representative of the difference between two unblocked summed signals. Each node blocks its summed signal if the signal is not representative of a true voice signal. A null signal is supplied at the output terminal during the absence of unblocked summed signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.