The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 07, 2000
Filed:
Jan. 28, 1998
Danny Amrany, Wayside, NJ (US);
Arnold Muralt, Fair Haven, NJ (US);
Globespan Semiconductor, Inc., Red Bank, NJ (US);
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 elimination filter is a low-pass filter configured to substantially block the passage of signals above the frequency of the ring signal (e.g., 20 hertz).