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. 02, 1982
Filed:
Jun. 30, 1980
Charles W Chambers, Jr, Downers Grove, IL (US);
Tellabs, Inc., Lisle, IL (US);
Abstract
An improved impedance canceller circuit, for use with two-wire transmission systems of the type encountered in telephony, is adapted to be interfaced with the wires and operates in a manner to effectively eliminate or cancel an unwanted impedance across the wires. The impedance canceller includes a current source, and essentially supplies on the wires all of the current that would otherwise be required by the unwanted impedance in response to a metallic voltage applied across the wires by a signal source, so that the signal source does not supply such current and the unwanted impedance appears as an open circuit to the metallic voltage. At the same time, the impedance canceller provides common mode rejection to longitudinal voltages on the wires.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile