Method and apparatus for the generation of analog telephone signals in digital subscriber line access systems
US6208637A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 15, 1999 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Jan 15, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2213/13298
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for providing analog telephony services over a digital subscriber loop access system is presented. Digital subscriber loop technologies including Asymmetric Digital Subscriber Loop (ADSL) leave existing POTs services undisturbed by utilizing spectrum above the POTs band for data services. An Asynchronous Transfer Mode (ATM) cell mapping is utilized on an ADSL linecard which permits flexible mapping of compressed or uncompressed voice signals into ATM cells along with overhead and signaling channels. Echo cancellation is used to enhance the voice quality in compressed voice signals. The ATM cells can be transmitted to a subscriber residence or a business and one to four additional analog telephony lines supported a receiving units, in addition to data services. This allows the first telephone line to be operated in the traditional manner as an analog connection over the twisted wire pair, data services provided in the ADSL connection, and additional phone lines to be supported without the installation of more twisted wire pair connections to the residence or business.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.