System and method for embedding digital information in a dial tone signal
US6661880B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2001 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | Jan 5, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/06
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Systems and methods for embedding, detecting and extracting access information from a dial tone of a private branch exchange system. The access information is embedded at the zero crossings of the dial tone. This has a minimal effect on the audible quality of the dial tone. A connecting device, such as a modem, receives the altered dial tone having access information. The access information is extracted by the connecting device and displayed to a user. The access information is automatically downloaded by the connecting device upon connecting to the private branch exchange without interaction from a user by having the connecting device go off hook such that the dial tone is received. The connecting device detects, extracts and displays the access information. After the access information is displayed to a user, the connecting device can await further user interaction or immediately make use of the access information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.