Method and apparatus for detecting a telephone CPE alerting signal
US6122353A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1997 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Jul 14, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/428
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for verifying that a CAS (Customer Premises Equipment Alerting Signal) detect signal, which indicates the presence of a CAS on a transmission channel, is a valid detect signal, includes structure and process steps for suppressing a signal originating at a local telephone in response to the CAS detect signal. A determination is made whether the CAS detect signal remains in a predetermined condition at a predetermined time after the local telephone signal is suppressed. A validity signal is output when the CAS detect signal remains in the predetermined condition at the predetermined time. False detections are thereby minimized by ignoring detections caused by a signal originating at the local telephone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.