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US3745253A Expired / Lapsed US ⏱️ 0.0 years remaining

Time division switching system

Assignee: AT&T Inc
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Filing: 1972-02-09
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Granted: 1973-07-10
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Expires: 1992-02-09
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Abstract

Abstract A time division communication system wherein a plurality of time slots occurs in repetitive cycles includes a plurality of stations each having a circuit for selectively coupling the associated station to first, second and third common buses, and a network for transferring signals from a first selected station to a second selected station in a distinct time slot. Each coupling circuit is operative to store signal samples from one of the first and third common buses, couple the stored signal to the associated line, and selectively connect the associated station to the second common bus during a distinct time slot. The signal transfer network receives a signal sample from a selected first coupling circuit store via the first bus and a sample of the signal appearing on the selected first station output via the second bus, generates a signal corresponding to the difference between the applied signal samples and applies the generated signal to the second station coupling circuit via the third common bus.

Inventors

  • 👤 R Carbrey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 03:35
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H04J; H04J3/00; H04J3/02; H04J3/04; H04J3/047

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 211 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of lines, first, second and third common buses, each line having means associated therewith for storing a signal incoming to said line received from said third common bus, means for coupling said stored signal from said store to said associated line, and means for coupling said associated line to said second common bus, and means operative in a distinct time slot for transferring a signal outgoing from a first line to a second line comprising means for applying the signal from the storing means associated with said first line to said first common bus, means for applying the sum of the coupled stored signal and the outgoing signal appearing on said first line to said second common bus, means connected to said first common bus and to said second common bus jointly responsive to the stored signal on said first common bus and the sum signal on said second common bus for removing said coupled stored signal from said sum signal, and means for applying the resulting signal corresponding to said first line outgoing signal from said removing means to the storing means associated with said second line via said third common bus.
Claim 2
Dependent Claim 211 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of lines, first, second and third common buses, each line having means associated therewith for storing a signal incoming to said line received from said third common bus, means for coupling said stored signal from said store to said associated line, and means for coupling said associated line to said second common bus, and means operative in a distinct time slot for transferring a signal outgoing from a first line to a second line comprising means for applying the signal from the storing means associated with said first line to said first common bus, means for applying the sum of the coupled stored signal and the outgoing signal appearing on said first line to said second common bus, means connected to said first common bus and to said second common bus jointly responsive to the stored signal on said first common bus and the sum signal on said second common bus for removing said coupled stored signal from said sum signal, and means for applying the resulting signal corresponding to said first line outgoing signal from said removing means to the storing means associated with said second line via said third common bus.
Claim 3
Dependent Claim 220 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; each station having an associated circuit including means for storing a signal incoming to said station from said third common bus and means for coupling said stored signal to said associated station; and means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, means connected to said first common bus and said second common bus responsive to the signal on said first station circuit storing means appearing on said first common bus and to the sum of the first station coupled stored signal and the signal outgoing from said first station appearing on said second common bus for cancelling said coupled stored signal in said sum signal on said second common bus with said stored signal on said first common bus, and means for applying the resulting signal corresponding to said first station outgoing signal from said cancelling means to said third common bus.
Claim 4
Dependent Claim 220 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; each station having an associated circuit including means for storing a signal incoming to said station from said third common bus and means for coupling said stored signal to said associated station; and means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, means connected to said first common bus and said second common bus responsive to the signal on said first station circuit storing means appearing on said first common bus and to the sum of the first station coupled stored signal and the signal outgoing from said first station appearing on said second common bus for cancelling said coupled stored signal in said sum signal on said second common bus with said stored signal on said first common bus, and means for applying the resulting signal corresponding to said first station outgoing signal from said cancelling means to said third common bus.
Claim 5
Dependent Claim 173 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; each station having an associated circuit including signal storing means and means for coupling said stored signal to said associated station; and means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, coupling means having a first input connected to said first common bus, a second input connected to said second common bus, and an output connected to said third common bus and comprising means for subtracting the signal on said first input from twice the signal on said second input in said distinct time slot, and means for applying the resultant difference signal to said output.
Claim 6
Dependent Claim 173 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; each station having an associated circuit including signal storing means and means for coupling said stored signal to said associated station; and means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, coupling means having a first input connected to said first common bus, a second input connected to said second common bus, and an output connected to said third common bus and comprising means for subtracting the signal on said first input from twice the signal on said second input in said distinct time slot, and means for applying the resultant difference signal to said output.
Claim 7
Dependent Claim 65 words
A time division communicAtion system according to claim 3 wherein the means in said associated circuit for coupling the stored signal to the associated station comprises amplifying means and impedance means, said amplifying means including an input connected to said storing means and an output connected to one terminal of said impedance means, the other terminal of said impedance means being connected to said station.
Claim 8
Dependent Claim 63 words
A time division communication system according to claim 4 wherein said amplifying means comprises an insulated gate field effect transistor having a source electrode, a drain electrode and a gate electrode, said gate electrode being connected to said storing means, said drain electrode being connected to a voltage source, and said source electrode being connected to said one terminal of said impedance means.
Claim 9
Dependent Claim 193 words
A time division communication system according to claim 4 wherein each of said first, second, and third connecting means comprises a semiconductor bidirectional switch having first, second and control electrodes, each switch being responsive to a signal applied to its control electrode for providing a conductive path between its first and second electrodes, the first electrode of said first switch being connected to said first common bus, the second electrode of said first switch being connected to said first station storing means, the first electrode of said second switch being connected to said second common bus and the second electrode of said second switch being connected to said first station, the first electrode of said third switch being connected to said third common bus and the second electrode of said third switch being connected to said second station storing means, and further comprising control means for generating first, second, and third control signals, means for applying said first control signal to said first switch control electrode, means for applying said second control signal to said second switch control electrode, and means for applying said third control signal to said third switch control electrode.
Claim 10
Dependent Claim 56 words
A time division communication system according to claim 6 wherein each of said semiconductor bidirectional switches comprises an insulated gate field effect transistor having a source electrode, a drain electrode and a gate electrode, said first electrode being said source electrode, said second electrode being said drain electrode, and said control electrode being said gate electrode.
Claim 11
Dependent Claim 282 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second, third and fourth common buses; each station having an associated circuit including signal storing means and means for coupling said stored signal to said associated station; means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station circuit storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, means connected to said first common bus and said second common bus responsive to the signal appearing on said first common bus and the first station coupled stored signal and the signal outgoing from said first station appearing on said second common bus for producing a signal corresponding to the signal outgoing from said first station, and means for applying the said produced signal to said third common bus; and means for transferring a signal from said second station to said first station in said distinct time slot including fourth means for connecting said second station to said fourth common bus, means connected to said third and fourth common buses responsive to the signal on said second station circuit storing means applied to said third common bus and the second station coupled stored signal and the signal outgoing from said second station applied to said fourth common bus foR generating a signal corresponding to the signal outgoing from said second station, and means for applying said generated signal to said first common bus.
Claim 12
Dependent Claim 282 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second, third and fourth common buses; each station having an associated circuit including signal storing means and means for coupling said stored signal to said associated station; means for transferring a signal from a first station to a second station in a distinct time slot comprising first means for connecting said first station circuit storing means to said first common bus, second means for connecting said first station to said second common bus, and third means for connecting said second station storing means to said third common bus, means connected to said first common bus and said second common bus responsive to the signal appearing on said first common bus and the first station coupled stored signal and the signal outgoing from said first station appearing on said second common bus for producing a signal corresponding to the signal outgoing from said first station, and means for applying the said produced signal to said third common bus; and means for transferring a signal from said second station to said first station in said distinct time slot including fourth means for connecting said second station to said fourth common bus, means connected to said third and fourth common buses responsive to the signal on said second station circuit storing means applied to said third common bus and the second station coupled stored signal and the signal outgoing from said second station applied to said fourth common bus foR generating a signal corresponding to the signal outgoing from said second station, and means for applying said generated signal to said first common bus.
Claim 13
Dependent Claim 214 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; means for generating first, second and third control signals; each station having an associated coupling circuit comprising storing means, means responsive to said first control signal for connecting said storing means to said first common bus, means for coupling the signal in said storing means to said associated station, means responsive to said second control signal for connecting said associated station to said second common bus, and means responsive to said third control signal for connecting said associated station to said third common bus, and means operative in a distinct time slot for transferring a signal from a first station to a second station comprising means for applying said first and second control signals to said first station coupling circuit, means for applying said third control signal to said second station coupling circuit, and means having a first input connected to said first common bus, a second input connected to said second common bus, and an output connected to said third common bus for subtracting the signal on said first input from twice the signal on said second input and for applying the resultant difference to said output.
Claim 14
Dependent Claim 214 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second and third common buses; means for generating first, second and third control signals; each station having an associated coupling circuit comprising storing means, means responsive to said first control signal for connecting said storing means to said first common bus, means for coupling the signal in said storing means to said associated station, means responsive to said second control signal for connecting said associated station to said second common bus, and means responsive to said third control signal for connecting said associated station to said third common bus, and means operative in a distinct time slot for transferring a signal from a first station to a second station comprising means for applying said first and second control signals to said first station coupling circuit, means for applying said third control signal to said second station coupling circuit, and means having a first input connected to said first common bus, a second input connected to said second common bus, and an output connected to said third common bus for subtracting the signal on said first input from twice the signal on said second input and for applying the resultant difference to said output.
Claim 15
Dependent Claim 335 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second, third and fourth common buses; means for generating first, second, third and fourth control signals; each station having an associated coupling circuit comprising storing means, means responsive to said first control signal for connecting said storing means to said first common bus, means for coupling the signal in said storing means to said associated station, means responsive to said second control signal for connecting said associated station to said second common bus, means responsive to said third control signal for connecting said associated station storing means to said third common bus, and means responsive to said fourth control signal for connecting said associated station to said fourth common bus; means operative in a distinct time slot for transferring a signal from a first station to a second station comprising means for applying said first and second control signals to said first station coupling circuit, means for applying said third control signal to said second station coupling circuit, means responsive to the signal in said first storing means appearing on said first common bus and to said first station coupled stored signal and the outgoing signal from said first station appearing on said second common bus for producing a signal corresponding to the first station outgoing signal, and means for applying said produced signal to said third common bus; and means for transferring the signal from said second station to said first station in said distinct time slot including means for applying said fourth control signal to said second station coupling circuit, means responsive to the signal in said second station storing means appearing on said third bus and to the second station stored signal and the outgoing signal from said second station appearing on said fourth common bus for generating a signal corresponding to the outgoing signal from said second station, and means for applying said generated signal to said first common bus.
Claim 16
Dependent Claim 335 words
A time division communication system wherein a plurality of time slots occurs in repetitive cycles comprising a plurality of stations; first, second, third and fourth common buses; means for generating first, second, third and fourth control signals; each station having an associated coupling circuit comprising storing means, means responsive to said first control signal for connecting said storing means to said first common bus, means for coupling the signal in said storing means to said associated station, means responsive to said second control signal for connecting said associated station to said second common bus, means responsive to said third control signal for connecting said associated station storing means to said third common bus, and means responsive to said fourth control signal for connecting said associated station to said fourth common bus; means operative in a distinct time slot for transferring a signal from a first station to a second station comprising means for applying said first and second control signals to said first station coupling circuit, means for applying said third control signal to said second station coupling circuit, means responsive to the signal in said first storing means appearing on said first common bus and to said first station coupled stored signal and the outgoing signal from said first station appearing on said second common bus for producing a signal corresponding to the first station outgoing signal, and means for applying said produced signal to said third common bus; and means for transferring the signal from said second station to said first station in said distinct time slot including means for applying said fourth control signal to said second station coupling circuit, means responsive to the signal in said second station storing means appearing on said third bus and to the second station stored signal and the outgoing signal from said second station appearing on said fourth common bus for generating a signal corresponding to the outgoing signal from said second station, and means for applying said generated signal to said first common bus.
Claim 17
Dependent Claim 198 words
A time division communication system according to claim 10 wherein said signal producing means comprises a first operational amplifier having first and second inputs and an output, said first input being coupled to said first common bus, said second input being coupled to said second common bus, and said output being connected to said third common bus, said first operational amplifier being opeRative to subtract the signal on said first input from twice the signal on said second input and to apply a signal corresponding to the resultant difference to said output, and said signal generating means comprising a second operational amplifier having first and second inputs and an output, the first input of said second amplifier being coupled to said third common bus, the second input of said second amplifier being coupled to said fourth common bus, and the output of said second amplifier being connected to said first common bus, said second amplifier being operative to subtract the signal on the first input of said second amplifier from twice the signal on the second input of said second amplifier and to apply a signal corresponding to the resultant difference to the output of said second amplifier.

References Cited (Backward Citations)

US3251947A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-07-09 1977-01-08 1977-07-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-07-09 1981-01-08 1981-07-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-07-09 1985-01-08 1985-07-10 $7700.00 Window Closed / Lapsed

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