Passive splitter filter for digital subscriber line voice communication for complex impedance terminations
US6137880A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 1999 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Aug 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2213/13396
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A dual-mode filter network for an Asymmetric Digital Subscriber Line (ADSL) has a first frequency response when the Plain Old Telephone Service (POTS) telephone is on-hook and has a second frequency response when the POTS telephone is off-hook. A detector is used to determine the on-hook/off-hook status. The dual-mode filter network may be situated at the central unit and connected to a Public Switched Telephone Network (PSTN) while the detector at the remote unit connected between the POTS low pass filter and the POTS telephone. In such case, the detector outputs a signal which is transmitter via the twisted pair on an overhead channel. Alternatively, the dual-mode filter and the detector may be co-located at either the central unit or at the remote unit. Regardless of where it, or the detector are located, the dual-mode filter network has at least different combinations of components which are activated, depending on the on-hook/off-hook status of the POTS phone. In addition, a single-mode filter instead of the dual-mode filter can be used at the remote unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.