US3859468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Redundant data transmission arrangement
Assignee: AT&T Inc
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Filing: 1973-07-25
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Granted: 1975-01-07
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Expires: 1993-07-25
Abstract
Abstract A loop data transmission arrangement is disclosed in which a plurality of transmission terminals are serially connected to a base terminal by a primary transmission line and a secondary transmission line over which time-divided data signals are transmitted in opposite directions by the base terminal. Each transmission terminal and the base terminal are equipped with individual fault detectors to monitor signal reception on both the primary and secondary lines. The transmission terminals contain storage devices for storing signals from the fault detectors. In addition, the transmission terminals contain circuitry responsive to the signal outputs of the fault detectors and the signals stored in the storage devices for controlling transmission of signals on the primary and secondary lines. The base terminal contains circuitry for responding to the detection of a fault on one of the lines by terminating data signal transmission on the other line. The base terminal is also capable of stopping data transmission on both lines. The cooperative operation of the transmission terminals and the base terminal when a transmission fault occurs results in the isolation of the fault and the restoration of communication by selectively effecting connections between the primary and secondary lines.
Inventors
- 👤 Nicholas Kimbrough Smith
- 👤 James Bartel Truesdale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:38
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/02; H04M9/022; H04M9/025; H04L; H04L12/00; H04L12/28; H04L12/42; H04L12/437
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
312 words
In a data transmission arrangement comprising a plurality of transmission terminals serially connected in a primary and a secondary transmission line, a transmission terminal for receiving signals from said primary transmission line at a primary receiving port, for transmitting signals to said primary transmission line at a primary transmitting port, for receiving signals from said secondary transmission line at a secondary receiving port and for transmitting signals to said secondary transmission line at a secondary transmitting port, comprising: a first fault detector connected to said primary receiving port for generating first control signals indicating that a transmission fault has occurred on said primary transmission line; a second fault detector connected to said secondary receiving port for generating second control signals indicating that a transmission fault has occurred on said secondary transmission line; a first storage means connected to said first fault detector and said second fault detector for storing said first control signals generated by said first fault detector when said second fault detector subsequently generates said second control signals; first gating means responsive to output signals from said first storage means for inhibiting the transmission to said secondary transmitting port of signals received at said secondary receiving port when said first storage means stores said first control signals; a signal processing means comprising an input port and an output port for processing time-divided signals to remove signals appearing in a selected time slot and to insert signals in that time slot; second gating means responsive to said first control signals for gating signals appearing at said secondary receiving port to said input port of said signal processing means when said first fault detector generates said first control signals indicating a transmission fault has occurred; and third gating means connected to said output port of said signal processing means for gating signals appearing at said output port to said primary transmitting port.
Claim 2
Dependent Claim
312 words
In a data transmission arrangement comprising a plurality of transmission terminals serially connected in a primary and a secondary transmission line, a transmission terminal for receiving signals from said primary transmission line at a primary receiving port, for transmitting signals to said primary transmission line at a primary transmitting port, for receiving signals from said secondary transmission line at a secondary receiving port and for transmitting signals to said secondary transmission line at a secondary transmitting port, comprising: a first fault detector connected to said primary receiving port for generating first control signals indicating that a transmission fault has occurred on said primary transmission line; a second fault detector connected to said secondary receiving port for generating second control signals indicating that a transmission fault has occurred on said secondary transmission line; a first storage means connected to said first fault detector and said second fault detector for storing said first control signals generated by said first fault detector when said second fault detector subsequently generates said second control signals; first gating means responsive to output signals from said first storage means for inhibiting the transmission to said secondary transmitting port of signals received at said secondary receiving port when said first storage means stores said first control signals; a signal processing means comprising an input port and an output port for processing time-divided signals to remove signals appearing in a selected time slot and to insert signals in that time slot; second gating means responsive to said first control signals for gating signals appearing at said secondary receiving port to said input port of said signal processing means when said first fault detector generates said first control signals indicating a transmission fault has occurred; and third gating means connected to said output port of said signal processing means for gating signals appearing at said output port to said primary transmitting port.
Claim 3
Dependent Claim
135 words
The transmission arrangement of claim 1 wherein said transmission terminal further comprises: a second storage means connected to said first fault detector and to said second fault detector for storing said second control signals generated by said second fault detector when said first fault detector generates first control signals indicating a transmission fault has occurred; wherein said third gating means is connected to said second storage means for inhibiting the gating of signals from said output port of said signal processing means to said primary transmitting port when said second storage means stores second control signals indicating a transmission fault has occurred; and fourth gating means connected to said output port of said signal processing means and to said second fault detector for gating signals appearing at said output port to said secondary transmitting port.
Claim 4
Dependent Claim
132 words
The transmission arrangement of claim 2 wherein said transmission terminal further comprises: means connected to said first storage means and to said second fault detector for generating first output signals when said first storage means stores first control signals indicating a transmission fault has occurred and said second fault detector generates second control signals indicating a transmission fault has occurred; means for gating said first output signals to said secondary transmitting port; means connected to said second storage means and said first fault detector for generating second output signals when said second storage means stores second control signals indicating a transmission fault has occurred and said first fault detector generates first control signals indicating a transmission fault has occurred; and means for gating said second output signals to said primary transmitting port.
Claim 5
Dependent Claim
151 words
A data transmission terminal for operation in a loop transmission system comprising first and second transmission lines, the combination comprising: first and second input ports for connection to first and second input lines respectively; first and second output ports for connection to first and second output lines respectively; first and second detector means for monitoring information received on said first and second input ports ane for generating normal and fault output signals indicating the presence and absence of signals at said input ports; register means responsive to the output signals of said detector means for generating state signals; switching means responsive to said state signals and said detector means output signals for selectively connecting said first and second input ports to said first and said second output ports; and signalling means responsive to said state signals and said detector output signals for generating and transmitting restart signals on said transmission lines.
Claim 6
Dependent Claim
151 words
A data transmission terminal for operation in a loop transmission system comprising first and second transmission lines, the combination comprising: first and second input ports for connection to first and second input lines respectively; first and second output ports for connection to first and second output lines respectively; first and second detector means for monitoring information received on said first and second input ports ane for generating normal and fault output signals indicating the presence and absence of signals at said input ports; register means responsive to the output signals of said detector means for generating state signals; switching means responsive to said state signals and said detector means output signals for selectively connecting said first and second input ports to said first and said second output ports; and signalling means responsive to said state signals and said detector output signals for generating and transmitting restart signals on said transmission lines.
Claim 7
Dependent Claim
70 words
A data transmission terminal in accordance with claim 4 wherein said register means comprises: first and second flip-flops respectively associated with said first and second threshold detectors; and means jointly responsive to said detector means fault output signals for setting the one of said flip-flops associated with the first one of said detector means to generate a fault output signal indicating the absence of signals on the associated input port.
Claim 8
Dependent Claim
78 words
A data transmission terminal in accordance with claim 5 wherein said signalling means comprises: means responsive to said state signals and said detector means fault output signals for generating and transmitting restart signals on said first output port when said first input port was the first to exhibit the absence of signals and for generatinG and transmitting restart signals on said second output port when said second input port was the first to exhibit the absence of signals.
Claim 9
Dependent Claim
41 words
A data transmission terminal in accordance with claim 6 wherein each data transmission terminal further comprises: means responsive to said restart signal for resetting the one of said flip-flops associated with the one of said input ports receiving said restart signals.
Claim 10
Dependent Claim
58 words
A data transmission terminal in accordance with claim 4 wherein said signalling means further comprises means responsive to fault output signals generated by the detector means associated with one of said input ports, commencing after the setting of the flip-flop associated with the other of said input port for generating restart signals on both of said output ports.
Claim 11
Dependent Claim
248 words
In a data transmission arrangement which comprises first and second transmission lines, a base terminal connected to said transmission lines for transmitting time-divided signals in a first direction on said first line and in a second direction on said second line, a plurality of transmission terminals serially connected in both of said transmission lines and a fault isolation arrangement for isolating transmission line faults by opening the serial connection of said first line and connecting said first line to said second line in the transmission terminal adjacent to the fault on one side and opening the serial connection of said second line and connecting said second line to said first line in a transmission connecting said second line to said first lin in a transmission terminal adjacent to said fault on the other side; a reconfiguration arrangement, comprising: means located in said base terminal for momentarily interrupting the time-divided signals on both of said first and said second transmission lines and wherein said transmission terminals further comprise: a register circuit for generating state signals indicating that the transmission terminal associated therewith is adjacent to a fault; a restart arrangement responsive to said state signals and to the interruption of signals on both said first and said second lines for generating and transmitting restart signals on both said first and second lines; and circuit arrangements responsive to said restart signals for disconnecting interconnections between said first and said second lines and for reestablishing the serial connection of said terminals.
Claim 12
Dependent Claim
248 words
In a data transmission arrangement which comprises first and second transmission lines, a base terminal connected to said transmission lines for transmitting time-divided signals in a first direction on said first line and in a second direction on said second line, a plurality of transmission terminals serially connected in both of said transmission lines and a fault isolation arrangement for isolating transmission line faults by opening the serial connection of said first line and connecting said first line to said second line in the transmission terminal adjacent to the fault on one side and opening the serial connection of said second line and connecting said second line to said first line in a transmission connecting said second line to said first lin in a transmission terminal adjacent to said fault on the other side; a reconfiguration arrangement, comprising: means located in said base terminal for momentarily interrupting the time-divided signals on both of said first and said second transmission lines and wherein said transmission terminals further comprise: a register circuit for generating state signals indicating that the transmission terminal associated therewith is adjacent to a fault; a restart arrangement responsive to said state signals and to the interruption of signals on both said first and said second lines for generating and transmitting restart signals on both said first and second lines; and circuit arrangements responsive to said restart signals for disconnecting interconnections between said first and said second lines and for reestablishing the serial connection of said terminals.
Claim 13
Dependent Claim
252 words
The data transmission arrangement of claim 9 wherein said fault isolation arrangement comprises: means, located in said base terminal, responsive to an interruption of signals on either of said first transmission lines for interrupting the transmission on the other of said lines; determining means in each of said transmission terminals responsive to the interruption of signals on both of said transmission lines for generating output signals indicating, with respect to the associated transmission terminal, which of said lines was the first to exhibit signal interruption; a first switching arrangement in each of said transmission terminals responsive to said determining means for disconnecting the serial connection of said second line and connecting said second line to said first line when said first line is the first to exhibit signal interruption; a second switching arrangement in each of said transmission terminals responsive to said determining means for disconnecting the serial connection of said first line and connecting said first line to said second line when said second line was the first to exhibit signal interruption; means responsive to said determining means for transmitting restart signals on the one of said transmission lines which was the first to exhibit signal interruption; means in each of said transmission terminals responsive to restart signals received on said transmission lines for maintaining their serial connection in said first and said second line; an means located in said base terminal responsive to said Restart signals for reestablishing the transmission of time-divided signals on said first and said second lines.
Claim 14
Dependent Claim
89 words
The fault isolation arrangement in accordance with claim 10 wherein said register circuits comprise a first flip-flop associated with said first line and a second flip-flop associated with said second line; means responsive to said determining means output signals and the interruption of signals on both of said lines for setting the one of said flip-flops associated with the first transmission line to exhibit signal interruption; and means responsive to said restart signals for resetting the flip-flop associated with the transmission line on which said restart signals are received.
References Cited (Backward Citations)
US3519935A
Cited
US3519750A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |