Patent US5087990A successfully refreshed from Google Patents.
Patent EP0112716A2 successfully refreshed from Google Patents.
EP0112716A2
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EP
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Secondary channel method and apparatus
Assignee: General Datacomm Inc
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Filing: 1983-12-21
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Granted: —
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Expires: 2003-12-21
Abstract
Abstract A secondary data channel is described for use in a four-wire communication system in which there is continuous wire between each of two coupling transformers at a first station and each of two coupling transformers at a second station. In accordance with the invention, the transformer windings at each station that are connected to the transmission line wires are equipped with center taps G that are connected to a secondary channel data set. By these means a secondary data signal can be transmitted from one station to another by applying a signal to the center taps of the two coupling transformers at one station and receiving such signals from the center taps of the two coupling transformers at the other station.
Inventors
- 👤 Hugh Michael Goldberg
- 👤 Lawrence Charles Dombrowski
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 20:34
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/20; H04B; H04B17/00; H04B17/0082; H04B17/0087; H04L1/00; H04L1/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
202 words
l. In a data communication system in which first and second stations are interconnected by a four-wire transmission line in which each wire of said transmission line is continuous between said first and second stations, apparatus providing for a secondary data channel comprising: first and second coupling transformers at said first station for coupling a primary data set transmitter to a first pair of wires and a primary data set receiver to a second pair of wires in said four-wire transmission line, and third and fourth coupling transformers at said second station for coupling a primary data set receiver and a primary data set transmitter to said first and second pairs of wires in said four-wire transmission line, each of said first, second, third and fourth transformers including a center-tapped winding having first and second terminals that are connected to one of said of pairs of wires in said four-wire transmission line interconnecting said stations and a center-tap, the center-taps of said first and second transformers being connected to a first secondary data set associated with said first station and the center taps of said third and fourth transformers being connected to a second secondary data set associated with said second station.
Claim 2
Dependent Claim
28 words
The apparatus of claim 1 further comprising first and second secondary data'sets, each secondary data set including a transmitter and a receiver equipped for full or half-duplex operation.
Claim 3
Dependent Claim
233 words
In a data communication system in which: first and second coupling transformers are located at a first station for coupling a primary data set transmitter to a first pair of wires and a primary data set receiver to a second pair of wires in a four-wire transmission line, and third and fourth coupling transformers are located at a second station for coupling a primary data set receiver and a primary data set transmitter to said first and second pairs of wires in said four-wire transmission line, each of said first, second, third and fourth transformers including a first winding connected to a primary data set transmitter or receiver and a second winding connected to one of said pairs of wires in said transmission line, and the wires of said transmission line are continuous between the second windings of said first and second coupling transformers at said first station and the second windings of said third and fourth coupling transformers at said second station, apparatus for providing a secondary data channel comprising: center taps in the second windings of each of said first, second, third and fourth transformers, means for connecting said center taps of the two transformers at one station to a first secondary channel data set associated therewith, and means for connecting said center taps of the two transformers at the other station to a second secondary channel data set associated therewith.
Claim 4
Dependent Claim
29 words
The apparatus of claim 3 further comprising first and second secondary data sets, each secondary data set including a transmitter and a receiver equipped for full or half-duplex operation.
Claim 5
Dependent Claim
215 words
In a data communication system in which: first and second coupling transformers are located at a first station for coupling a primary data set transmitter to a first pair of wires and a primary data set receiver to a second pair of wires in a four-wire transmission line, and third and fourth coupling transformers are located at a second station for coupling a primary data set receiver and a primary data set transmitter to said first and second pairs of wires in said four-wire transmission line, each of said first, second, third and fourth transformers including a first winding connected to a primary data set transmitter or receiver and a second winding connected to one of said pairs of wires in said transmission line, and the wires of said transmission line are continuous between the second windings of said first and second coupling transformers at said first station and the second windings of said third and fourth coupling transformers at said second station, a method of providing for a secondary data channel comprising the steps of: applying secondary data signals to center taps in the second winding of the two transformers at one station and receiving said secondary data signals from center taps in the second winding of the two transformers at the other station.
References Cited (Backward Citations)
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