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:
Apr. 02, 1996
Filed:
Sep. 15, 1992
Richard J Cubbison, Jr, Westminster, CO (US);
AT&T Corp., Murray Hill, NJ (US);
Abstract
A non-invasive directional coupler (51) comprising a voltage probe (300) and a current probe (301) is used to detect and separate from each other digital pulses (quats) being transmitted in opposite directions on a digital ISDN subscriber loop 200 (U-interface 15). The voltage probe measures the sum of digital pulse voltage of the conductors (201, 202) of the loop while the current probe measures the difference of digital pulse currents of in the conductors. An equalizer (304) converts the difference of the currents into the difference of the corresponding voltages. The sum and difference voltage measurements are then added (305) and subtracted (306) respectively to obtain voltages for digital pulses propagating in each direction. The voltages are provided to a decoder (52) such as a protocol analyzer for processing to interpret the traffic being sent in each direction on the loop.