US3566031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct-current data set arranged for polar signaling and full duplex operation
Assignee: AT&T Inc
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Filing: 1968-12-23
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Granted: 1971-02-23
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Expires: 1988-12-23
Abstract
Abstract A data set receiver detects the direction and magnitude of the cumulative polar loop current on a full duplex two-wire line. The detected signals are applied to a signal slicer which is biased to discriminate between incoming and outgoing signals. The bias is modified to change the slicing level to compensate for the outgoing signal currents. Changes in the output of the slicer are momentarily precluded after transitions of the outgoing signals to filter out line transients. An alarm circuit for line signal failure is also included in the set.
Inventors
- 👤 John T Carbone
- 👤 Robert C Morris
- 👤 George Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:04
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/14; H04L5/1423
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
111 words
In a full duplex data set including means for applying direct-current signals to a communication line, means for detecting the magnitude of the cumulative signaling current in said line, and further means jointly operated by the magnitude of the cumulative signaling current in the line and the means for applying the direct-current signals to the line for recognizing incoming direct-current signals characterized in that said further means includes a signal slicer having an input connected to the detecting means and other means responsive to the applying means and controlled in accordance with the signals applied to the line by said applying means for varying the slicing level of the signal Slicer.
Claim 2
Dependent Claim
111 words
In a full duplex data set including means for applying direct-current signals to a communication line, means for detecting the magnitude of the cumulative signaling current in said line, and further means jointly operated by the magnitude of the cumulative signaling current in the line and the means for applying the direct-current signals to the line for recognizing incoming direct-current signals characterized in that said further means includes a signal slicer having an input connected to the detecting means and other means responsive to the applying means and controlled in accordance with the signals applied to the line by said applying means for varying the slicing level of the signal Slicer.
Claim 3
Dependent Claim
38 words
In a full duplex data set in accordance with claim 1 wherein said other means produces a bias voltage for said signal slicer, the magnitude of said bias voltage being controlled by the signals applied to the line.
Claim 4
Dependent Claim
33 words
In a full duplex data set in accordance with claim 2 wherein said detecting means produces a signal voltage having a magnitude designating the magnitude of the cumulative signaling current in the line.
Claim 5
Dependent Claim
28 words
In a full duplex data set in accordance with claim 3 wherein said signal slicer comprises a difference amplifier for comparing the signal voltage with the bias voltage.
Claim 6
Dependent Claim
140 words
A full duplex polar signaling data system having at least one local and one remote station, each station having means for impressing current on the signaling line so that the direction of the current impressed by each station corresponds to the data signal being transmitted and the magnitude and direction of the cumulative line current is determined by the currents impressed by both stations, and means for recovering incoming signals, said recovering means comprising: detecting means for producing a signal voltage having a magnitude controlled by the direction and magnitude of the line current; means for producing a bias voltage having a magnitude controlled by the direction of the current impressed on the line by the local station; and a signal slicer for opposing the signal voltage with the bias voltage to recover the incoming signals from the remote station.
Claim 7
Dependent Claim
140 words
A full duplex polar signaling data system having at least one local and one remote station, each station having means for impressing current on the signaling line so that the direction of the current impressed by each station corresponds to the data signal being transmitted and the magnitude and direction of the cumulative line current is determined by the currents impressed by both stations, and means for recovering incoming signals, said recovering means comprising: detecting means for producing a signal voltage having a magnitude controlled by the direction and magnitude of the line current; means for producing a bias voltage having a magnitude controlled by the direction of the current impressed on the line by the local station; and a signal slicer for opposing the signal voltage with the bias voltage to recover the incoming signals from the remote station.
Claim 8
Dependent Claim
20 words
A full duplex polar signaling data system in accordance with claim 5 wherein said signal slicer comprises a difference amplifier.
Claim 9
Dependent Claim
45 words
A full duplex polar signaling data system in accordance with claim 5 wherein said signal slicer further includes means at the output thereof for filtering out line transients caused by reversals in the direction of the current impressed on the line by the station thereat.
Claim 10
Dependent Claim
35 words
A full duplex polar signaling data system in accordance with claim 7 wherein said further means includes means responsive to any one of the reversals for momentarily precluding any output change of the signal slicer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-22 | 1974-08-24 | 1975-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-22 | 1978-08-24 | 1979-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-22 | 1982-08-24 | 1983-02-23 | $7700.00 | Window Closed / Lapsed |