Ring filter for pots communication system
US6144733A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1998 |
| Grant date | Nov 7, 2000 |
| Priority date | — |
| Expiry date | Jan 28, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/007
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An line interface circuit at a central office of a telecommunication system provides improved noise immunity to a ring signal. In accordance with one aspect of the invention, the line interface circuit includes a signal line having a first end for connection to a ring signal generating source and a second end for communication with a customer premises via a local loop. A POTS filter is electrically connected to the signal line. Preferably, the POTS filter is a relatively simple and thus inexpensive low-order filter, which may be implemented as a simple L-C circuit. The preferred embodiment of the present invention further includes a POTS communication device electrically connected to the signal line at a point between the POTS filter and the first end. In this regard, the POTS communications device broadly denotes any device designed to communicate information within the POTS frequency band, such as a telephone (e.g., voice information), a facsimile machine, a PSTN modem, etc. The circuit further includes a ring signal noise elimination filter integrally connected to the signal line and interposed between the POTS filter and the ring signal generating source. The ring signal noise …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.