US4381427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Subscriber loop system for voice and data
Assignee: Nortel Networks Ltd
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Filing: 1981-06-16
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Granted: 1983-04-26
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Expires: 2001-06-16
Abstract
Abstract A subscriber loop system in association with a TDM telephone system provides voice and data communication with a remote telephone station set and an associated data port. The subscriber loop system includes a voice path and a data path. Supervisory and signalling circuits in the telephone set are used for generating and registering call control signals pertaining to both voice and data calls. The call control signals are labelled and multiplexed with data signals by local and remote line interface circuits for transmission therebetween. A codec in the voice path is caused to couple call progress signals (i.e. dial tone, ring back) to the telephone set during a data call progress, for audible signalling to a user. Changeover relays are connected in combination with the data path and the line interface circuits such that the line interface circuits are bypassed in the event of power failure of the remote line interface circuit, to provide a more direct connection between the signalling and supervision circuits and the TDM telephone system whereby ordinary voice telephone service is maintained in the event of such failure.
Inventors
- 👤 William E. Cheal
- 👤 Gokal C. Gupta
- 👤 Faramarz Sepahmansour
- 👤 Avnish K. Aggarwal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:08
CPC Classifications
H; H04; H04M; H04M11/00; H04M11/06; H04M11/068; H04Q; H04Q11/00; H04Q11/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
986 words
A subscriber loop system for providing a voice call operation along a first conductor path between a user multiline function (UMF) telephone terminal and a time division multiplex (TDM) telephone system, and for providing a data call operation along a second conductor path between a data port and the TDM telephone system, the TDM system providing at least one signalling and supervision (SS) path for communication with a controller in the TDM telephone system, and providing a plurality of time divided communication paths for communication through the TDM telephone system, the UMF telephone terminal including an SS circuit for storing dial pad and key depressions for transmission to the controller and for storing signalling states transmitted from the controller, the subscriber loop system comprising: a line interface means including; a codec responsive to an enable signal directed thereto by the TDM telephone system, for receiving analog information signals from the first conductor path and encoding said information signals to provide corresponding digital information signals for transmission along one of the plurality of communication paths as designated by the enable signal and for receiving digital information signals from the designated communication path and decoding said information signals to provide corresponding analog information signals for transmission along the first conductor path, digital circuits for exchanging data and SS information signals between the second conductor path and the TDM telephone system, the digital circuits being responsive to an enable signal directed thereto by the TDM telephone system for receiving digital information signals from one of the plurality of communication paths as designated by the enable signal and converting said information signals to corresponding information signals in an operating signal format of the second conductor path, for transmission along the second conductor path, and for receiving information signals in the operating signal format of the second conductor path and converting said information signals to corresponding information signals in an operating signal format of the plurality of communication paths, a voice call storage means and a data call storage means, included in the digital circuits, for storing digital SS information signals corresponding to SS information signals received by the digital circuits in the operating signal format of the second conductor path and pertaining to SS functions of voice calls and of data calls respectively, for transmission along the SS path, and; a line controller connected to the digital circuit for controlling operation of the digital circuits in exchanges of SS information signals between the second conductor path and the SS path, the line controller being responsive to the designation of the SS path and an assertion of either of the two previously mentioned enable signals to; (a) cause the digital circuits to receive digital SS information signals from the SS path, (b) label the received SS information signals to provide voice call and data call information signals in accordance with which of the two enable signals is asserted, (c) cause the digital circuits to transmit SS information signals corresponding to the labelled SS information signals along the second conductor path, (d) cue SS information signals, received by the digital circuits from the second conductor path, in the voice call storage means and in the data call storage means in accordance with voice call and data call labels received in association with the SS information signals, and (e) cause the digital circuits to pass signal contents of the voice call storage means and the data call storage means to the SS path in accordance with respective assertions of the enable signals; a remote line interface means including; digital circuits for exchanging data information signals between the data port and the second conductor path and for exchanging SS information signals between the SS circuit of the UMF telephone terminal and the second conductor path, the ditigal circuits being responsive to a time defining characteristics in the information signals transmitted from the first line interface means along the second conductor path for converting data information signals received from the second conductor path to corresponding digital signals compatible with a predetermined operating signal format of the data port for transmission to the data port, and for converting data information signals received from the data port to corresponding data information signals compatible with the operating signal format of the second conductor path for transmission along the second conductor path to the first line interface means, and also, for converting SS information signals received from the second conductor path to corresponding SS information in a signal format compatible with operation of the SS circuit for transmission to the SS circuits and for receiving SS information signals from the SS circuit and converting said SS information signals to corresponding SS information signals compatible with the operating signal format of the second conductor path for transmission along the second conductor path to the first line interface means, a shift key manually operable by a user for designating functions of SS information signals originating at the UMF telephone terminal as pertaining to a voice call and alternately to a data call, a directory number key and a directory number indicator, the directory number key being manually operable by a user to request service for a data call, a remote line controller connected to the digital circuits and being responsive to designation at the shift key to label SS information signals for transmission along the second conductor path as pertaining to one of a voice call and a data call, and being responsive to a request for service at the directory number key for generating data call labelled SS information signals corresponding to a request for service code for transmission via the digital circuits and the second conductor path to the first line interface means, and being responsive to SS information signals labelled as pertaining to a data call and corresponding to either of service initiated and service terminated codes for accordingly causing a corresponding indication at the directory number indicator.
Claim 2
Dependent Claim
986 words
A subscriber loop system for providing a voice call operation along a first conductor path between a user multiline function (UMF) telephone terminal and a time division multiplex (TDM) telephone system, and for providing a data call operation along a second conductor path between a data port and the TDM telephone system, the TDM system providing at least one signalling and supervision (SS) path for communication with a controller in the TDM telephone system, and providing a plurality of time divided communication paths for communication through the TDM telephone system, the UMF telephone terminal including an SS circuit for storing dial pad and key depressions for transmission to the controller and for storing signalling states transmitted from the controller, the subscriber loop system comprising: a line interface means including; a codec responsive to an enable signal directed thereto by the TDM telephone system, for receiving analog information signals from the first conductor path and encoding said information signals to provide corresponding digital information signals for transmission along one of the plurality of communication paths as designated by the enable signal and for receiving digital information signals from the designated communication path and decoding said information signals to provide corresponding analog information signals for transmission along the first conductor path, digital circuits for exchanging data and SS information signals between the second conductor path and the TDM telephone system, the digital circuits being responsive to an enable signal directed thereto by the TDM telephone system for receiving digital information signals from one of the plurality of communication paths as designated by the enable signal and converting said information signals to corresponding information signals in an operating signal format of the second conductor path, for transmission along the second conductor path, and for receiving information signals in the operating signal format of the second conductor path and converting said information signals to corresponding information signals in an operating signal format of the plurality of communication paths, a voice call storage means and a data call storage means, included in the digital circuits, for storing digital SS information signals corresponding to SS information signals received by the digital circuits in the operating signal format of the second conductor path and pertaining to SS functions of voice calls and of data calls respectively, for transmission along the SS path, and; a line controller connected to the digital circuit for controlling operation of the digital circuits in exchanges of SS information signals between the second conductor path and the SS path, the line controller being responsive to the designation of the SS path and an assertion of either of the two previously mentioned enable signals to; (a) cause the digital circuits to receive digital SS information signals from the SS path, (b) label the received SS information signals to provide voice call and data call information signals in accordance with which of the two enable signals is asserted, (c) cause the digital circuits to transmit SS information signals corresponding to the labelled SS information signals along the second conductor path, (d) cue SS information signals, received by the digital circuits from the second conductor path, in the voice call storage means and in the data call storage means in accordance with voice call and data call labels received in association with the SS information signals, and (e) cause the digital circuits to pass signal contents of the voice call storage means and the data call storage means to the SS path in accordance with respective assertions of the enable signals; a remote line interface means including; digital circuits for exchanging data information signals between the data port and the second conductor path and for exchanging SS information signals between the SS circuit of the UMF telephone terminal and the second conductor path, the ditigal circuits being responsive to a time defining characteristics in the information signals transmitted from the first line interface means along the second conductor path for converting data information signals received from the second conductor path to corresponding digital signals compatible with a predetermined operating signal format of the data port for transmission to the data port, and for converting data information signals received from the data port to corresponding data information signals compatible with the operating signal format of the second conductor path for transmission along the second conductor path to the first line interface means, and also, for converting SS information signals received from the second conductor path to corresponding SS information in a signal format compatible with operation of the SS circuit for transmission to the SS circuits and for receiving SS information signals from the SS circuit and converting said SS information signals to corresponding SS information signals compatible with the operating signal format of the second conductor path for transmission along the second conductor path to the first line interface means, a shift key manually operable by a user for designating functions of SS information signals originating at the UMF telephone terminal as pertaining to a voice call and alternately to a data call, a directory number key and a directory number indicator, the directory number key being manually operable by a user to request service for a data call, a remote line controller connected to the digital circuits and being responsive to designation at the shift key to label SS information signals for transmission along the second conductor path as pertaining to one of a voice call and a data call, and being responsive to a request for service at the directory number key for generating data call labelled SS information signals corresponding to a request for service code for transmission via the digital circuits and the second conductor path to the first line interface means, and being responsive to SS information signals labelled as pertaining to a data call and corresponding to either of service initiated and service terminated codes for accordingly causing a corresponding indication at the directory number indicator.
Claim 3
Dependent Claim
100 words
A subscriber loop system as defined in claim 1 wherein the line controller is also responsive to a request for service code from the remote line controller followed by a service initiated code in response thereto from the TDM telephone system for asserting a switch codec signal, the subscriber loop system further comprising: gating means for directing the enable signal associated with a data call to the codec during assertion of the switch codec signal, whereby audible signalling normally associated with progress of a voice call is available at the associated UMF telephone terminal during progress of a data call.
Claim 4
Dependent Claim
247 words
A subscriber loop system as defined in claims 1 or 2 further comprising: a control conductor path for connection between the line interface means and the remote line interface means; in the line interface means, SS interface means responsive to designation of the SS path and assertion of the first mentioned enable signal for converting digital SS information signals from the SS path to corresponding SS information signals compatible with operation of the SS circuit in the UMF telephone terminal and for converting SS information signals from the UMF telephone terminal to corresponding SS information signals compatible with the operating signal format of the SS path for transmission along the SS path, changeover means connecting the digital circuits to the second conductor path and responsive to a changeover signal for disconnecting the digital circuits from the second conductor path, connecting the SS interface means to the second conductor path and providing access for transmission along the SS path; in the remote line interface means, a remote changeover means for connecting the remote line interface means to the second conductor and the SS circuit of the UMF telephone terminal, the remote changeover means being responsive to a failure of the local power supply for disconnecting the remote line interface means from the second conductor path and the UMF telephone terminal, for connecting the second conductor path directly to the UMF telephone, and for transmitting the changeover signal to the first line interface means via the control conductor path.
Claim 5
Dependent Claim
301 words
A subscriber loop system including a voice path having a voice loop and interface means for exchanging voice band signals, via the voice loop, between a TDM telephone system and a telephone set; a separate data path having a data loop for exchanging voice call control signals between a signalling and supervision circuit in the telephone set and the TDM telephone system; feed means for supplying operating current from the TDM telephone system along said loops for operation of the telephone set; and a data transmission system for utilizing the data loop and the signalling and supervision circuit to provide a data call feature, the data transmission system comprising: a data port; a line interface means for multiplexing information signals, the information signals corresponding to data signals, data call control signals and the voice call control signals from the TDM telephone system, for transmission along said data loop, and for demultiplexing information signals from the data loop to provide data signals, for transmission through the TDM telephone system, and data call control signals and voice call control signals for transmission to a controller in the TDM telephone system; a remote line interface means for multiplexing information signals, the information signals corresponding to data signals from the data port, data call control signals and voice call control signals from the signalling and supervision circuit, for transmission along said data loop to the line interface means, and for demultiplexing information signals transmitted along the data loop from the line interface means to provide data signals for transmission to the data port, and data call and voice call control signals for use in the signalling and supervision circuit whereby indicators and manually operable keys associated with the signalling and supervision circuit serve as a user interface for data calls in addition to voice calls.
Claim 6
Dependent Claim
301 words
A subscriber loop system including a voice path having a voice loop and interface means for exchanging voice band signals, via the voice loop, between a TDM telephone system and a telephone set; a separate data path having a data loop for exchanging voice call control signals between a signalling and supervision circuit in the telephone set and the TDM telephone system; feed means for supplying operating current from the TDM telephone system along said loops for operation of the telephone set; and a data transmission system for utilizing the data loop and the signalling and supervision circuit to provide a data call feature, the data transmission system comprising: a data port; a line interface means for multiplexing information signals, the information signals corresponding to data signals, data call control signals and the voice call control signals from the TDM telephone system, for transmission along said data loop, and for demultiplexing information signals from the data loop to provide data signals, for transmission through the TDM telephone system, and data call control signals and voice call control signals for transmission to a controller in the TDM telephone system; a remote line interface means for multiplexing information signals, the information signals corresponding to data signals from the data port, data call control signals and voice call control signals from the signalling and supervision circuit, for transmission along said data loop to the line interface means, and for demultiplexing information signals transmitted along the data loop from the line interface means to provide data signals for transmission to the data port, and data call and voice call control signals for use in the signalling and supervision circuit whereby indicators and manually operable keys associated with the signalling and supervision circuit serve as a user interface for data calls in addition to voice calls.
Claim 7
Dependent Claim
154 words
A subscriber loop system as defined in claim 4 wherein the interface means in the voice path is responsive to call enable signals coupled from the TDM telephone system for exchanging said voice band signals, the line interface means is responsive to a data call control signal corresponding to a request for service code from the remote line interface means, followed by a service initiated code being asserted in response thereto by the TDM telephone system, for asserting a switch signal, the subscriber loop system further comprising: gating means responsive to the switch signal for coupling data call enable signals generated in the TDM telephone system to the interface means to cause encoded call progress tone signals to be interfaced with the voice loop; whereby call progress tone signals generated in the TDM telephone system and related to the progress of the data call are audibly available to a user at the telephone set.
Claim 8
Dependent Claim
185 words
In a subscriber loop system as defined in claims 4 or 5 the data transmission system further comprising: in the remote line interface means, a power supply operable from a source of power other than a source of power related to the TDM telephone for supplying operating current to the remote line interface means, and changeover means for connecting the remote line interface means in series between the telephone set and the data loop in response to operating current from the power supply and in the absence of said operating current for disconnecting the remote line interface means and directly connecting the data loop to the telephone set, and for generating a changeover signal, in the line interface means, changeover means responsive to the changeover signal for connecting the interface means to the data loop, and for disconnecting the line interface means, whereby in the event that operating current is unavailable at the remote line interface means, voice call control signals continue to be exchanged between the telephone set and the controller in the TDM telephone system via the interface means and the data loop.
Claim 9
Independent Claim
179 words
A method for providing data communication in addition to voice communication via a subscriber loop system having voice and data paths for coupling analog voice signals and call control signals respectively between a TDM telephone system and a remote telephone set having dial pad, keys, indicators and a dial pad for interfacing call progress and control function with a user, the method comprising the steps of: (a) providing a data port in association with the remote telephone set; (b) distinguishing call control signals as pertaining to one of a voice call function and a data call function; and at opposite ends of the data path, (c) multiplexing data signals alternately with one of voice call control signals and data call control signals into a data transmission stream, (d) receiving the data transmission stream from the opposite end, and (e) demultiplexing the received data transmission to provide the call control signals and the data signals; whereby at the remote telephone set both data and voice call control signals are interfaced with a user via the dial pad, keys and indicators.
Claim 10
Independent Claim
179 words
A method for providing data communication in addition to voice communication via a subscriber loop system having voice and data paths for coupling analog voice signals and call control signals respectively between a TDM telephone system and a remote telephone set having dial pad, keys, indicators and a dial pad for interfacing call progress and control function with a user, the method comprising the steps of: (a) providing a data port in association with the remote telephone set; (b) distinguishing call control signals as pertaining to one of a voice call function and a data call function; and at opposite ends of the data path, (c) multiplexing data signals alternately with one of voice call control signals and data call control signals into a data transmission stream, (d) receiving the data transmission stream from the opposite end, and (e) demultiplexing the received data transmission to provide the call control signals and the data signals; whereby at the remote telephone set both data and voice call control signals are interfaced with a user via the dial pad, keys and indicators.
Claim 11
Dependent Claim
174 words
A subscriber loop system including interface circuitry for interfacing conductor paths in a subscriber loop with a telephone system, and remote apparatus connected with the subscriber loop, the remote apparatus including a centrally energized portion which depends on energizing current from the telephone system for its operation and a remotely energized portion which depends on energizing current from another source for its operation, the subscriber loop system being characterized by: said interface circuitry having a first configuration for normal operation and including changeover means responsive to a changeover signal for switching the interface circuit into a second configuration for limited operation; said remote apparatus having a first configuration for normal operation and including a remote changeover means responsive to interruption of the energizing current from said other source for switching the remote interface circuit into a second configuration for a limited operation of the centrally energized portion, and for generating the changeover signal; and means in the subscriber loop system for coupling the changeover signal from the remote apparatus to the line interface circuitry.
Claim 12
Dependent Claim
174 words
A subscriber loop system including interface circuitry for interfacing conductor paths in a subscriber loop with a telephone system, and remote apparatus connected with the subscriber loop, the remote apparatus including a centrally energized portion which depends on energizing current from the telephone system for its operation and a remotely energized portion which depends on energizing current from another source for its operation, the subscriber loop system being characterized by: said interface circuitry having a first configuration for normal operation and including changeover means responsive to a changeover signal for switching the interface circuit into a second configuration for limited operation; said remote apparatus having a first configuration for normal operation and including a remote changeover means responsive to interruption of the energizing current from said other source for switching the remote interface circuit into a second configuration for a limited operation of the centrally energized portion, and for generating the changeover signal; and means in the subscriber loop system for coupling the changeover signal from the remote apparatus to the line interface circuitry.
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) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |