Cable network data transmission system

• US 4,623,920 A
• Filed: 01/20/1983
• Issued: 11/18/1986
• Est. Priority Date: 04/15/1982
• Status: Expired due to Term

• Current Assignee: Le Groupe Videotron Limitee, Telecable Videotron Limitee
• Original Assignee: Le Groupe Videotron Limitee
• Inventors: Champagne, Jean-Paul, Dufresne, Michel, Scott, Pierre, Dufresne, Daniel, Courtney, John
• Primary Examiner(s): Buczinski, Stephen C.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/459,673
• Time in Patent Office: 1,398 Days
• Field of Search: 358/122, 358/123, 358/114
• US Class Current: 380/240
• CPC Class Codes: H04N 7/165 Centralised control of user terminal subsequent to an upstream request signal H04N7/17345; Registering at central by two-way working H04N7/17309
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

A system for providing television, information and data signals via a transmission network to selected subscribers, to groups of subscribers, or to all subscribers connected in common to the transmission network. An address code signal is stored at the subscriber station, and an option code signal is sent to the particular subscriber station from a head end of the network. Signals having an address portion designative of the option code or address code signal are sent down the transmission line and are translated by the subscriber station in the event the address matches the first and second code signal. Thus signals can be sent to all subscribers which have option codes designated by the address of data packets transmitted down the transmission line. These groups of subscribers can be all subscribers, individual smaller groups of subscribers, or a group consisting of even a single subscriber. The option codes can be changed from the head end at will. Consequently data can be transmitted to various subscribers designated form the head end under its complete control. The data can be control signals for controlling the unscrambling of pay-TV signals, software for operating a microcomputer peripheral, data to enable operation of a local television channel converter to facilitate selection of particular channels depending on service paid for, etc. Since the option codes can be changed from the head end, cheating of the system is inhibited and the requirement to send service personnel to each subscriber to enable the acquisition of changed services is avoided.

Claims

1. A signal transmission system comprising:

(a) a head end,

(b) a transmission medium, connected to the head end, for carrying signals from the head end,

(c) a plurality of subscriber stations connected to the transmission medium,

(d) means at said subscriber stations for receiving and storing predetermined station address signals from the transmission medium,

(e) means at said subscriber stations which have stored said station address signals, for receiving and storing program signals from said transmission medium having an address component which matches said stored address signals,

(f) means at said subscriber stations having certain ones of said station address signals for receiving further signals from the transmission medium, having an address component which matches said certain ones of said address signals, and for translating said further signals, said translation being dependent on the prior storage of said program signals.

10. A signal transmission system as defined in claim 1, 2 or 5 in which the transmission medium is a CATV network.

11. A signal transmission system as defined in claim 1, 2 or 5 in which the head end is comprised of means for generating said signals in asynchronous packets in HDLC format.

12. A signal transmission system as defined in claim 1, 2 or 5 in which the head end is comprised of a mass digital signal storage system for storing said signals in predetermined order, a buffer memory for storing sequential strings of said signals, and means for applying said strings of said digital signals to the transmission medium according to said order.

13. A signal transmission system as defined in claim 1, 2 or 5 in which the head end is comprised of a mass digital signal storage system for storing said signals in predetermined order, a buffer memory for storing sequential strings of said signals, and means for applying said strings of said digital signals to the transmission medium according to said order, a source of television signals, and means for applying the television signals to the transmission medium with said strings of said digital signals, in different frequency bands.

14. A signal transmission system as defined in claim 1, 2 or 5 in which the head end is comprised of signal source means for generating signals for transmission on the transmission medium, a mass digital signal storage system for carrying said signals in digital form according to a predetermined order, and for sequentially reading said signals, a buffer memory for storing sequential strings of said signals, means for applying said strings to the transmission medium in a predetermined frequency band, and means for applying broadcast televison signals to said transmission medium in other frequency bands.

2. A signal transmission system comprising:

(a) a head end,

(b) a transmission medium connected to the head end, for carrying signals from said head end,

(c) a plurality of subscriber stations connected to the transmission medium, in which each subscriber station includes

(i) means for storing a first predetermined address code signal,

(ii) means for receiving from the transmission medium and storing a second predetermined option code signal,

(iii) means for receiving and storing a signal having an address component designative of the first or second code signals, and

(iv) means for translating said latter signal in the event the address component matches said first or second code signals, and thereby enabling operation of the subscriber station in response thereto.

3. A signal transmission system as defined in claim 2, in which said translating means includes means for enabling said subscriber station to translate further signals in a manner prescribed by said latter signal upon reception by the subscriber station of signals having an address component designative of the first or second code signals.

4. A signal transmission system as defined in claim 3, further including means for receiving and translating signals from the transmission medium having either no address component or an address component restricted to said first predetermined code signal and for displaying said translated signal.

5. A signal transmission system comprising:

(a) a head end,

(b) a transmission medium connected to the head end, for carrying signals from the head end,

(c) a plurality of subscriber stations connected to the transmission medium, each station comprising

(i) first memory means for permanently storing a first address code signal,

(ii) second memory means for storing a service code signal,

(iii) third memory means for storing a control signal,

(iv) means for providing a signal to a display device,

(v) means for controlling the application of a signal broadcast on said transmission medium to the display device,

(vi) data acquisition circuit means for applying the service code signal to the second memory means in the event of reception from the transmission medium of a service code signal having an address component matching the address code signal, and for applying to and storing a control signal in the third memory means in the event of reception of a signal from the transmission medium having a component which is an address matching the service code signal and a control signal component, and

(vii) processor means for operating the controlling means according to the control signal in response to reception from the transmission medium of said broadcast signals of a kind controllable by said control signal.

6. A signal transmission system as defined in claim 5 in which the controlling means is comprised of a television signal unscrambler.

7. A signal transmission system as defined in claim 5 in which the controlling means is comprised of a television signal channel converter.

8. A signal transmission system as defined in claim 5 in which the controlling means is comprised of a video display generator.

9. A signal transmission system as defined in claim 5 in which the controlling means is comprised of a television signal unscrambler, a television signal channel converter, and a video display generator.

15. A subscriber station for connection to a tranmission medium for controlling the translation of signals carried by the transmission medium for application to a display device comprising:

(i) first memory means for permanently storing a first address code signal,

(ii) second memory means for storing a service code signal

(iii) third memory means for storing a control signal

(iv) means for providing a signal to a display device

(v) means for controlling the application of a signal broadcast on said transmission medium to the display device,

(vi) data acquisition circuit means for applying the service code signal to the second memory means in the event of reception from the transmission medium of a service code signal having an address component matching the address code signal, and for applying and storing a control signal to the third memory means in the event of reception of a signal from the transmission medium having an address component matching the service code signal and a control signal component, and

(vii) processor means for operating the controlling means according to the control signal in response to reception from the transmission line of said broadcast signals of a kind controllable by said control signal,

whereby a display signal is provided for application to the display device.

16. A signal transmission system as defined in claim 15 in which the controlling means is comprised of a television signal channel converter, for converting a predetermined display device channel to a broadcast television channel received from the transmission medium under control of the processor means according to the control signal.

17. A signal transmission system as defined in claim 15 in which the controlling means is comprised of a video display generator, for generating alphanumeric character and/or pattern signals under control of the processor means according to the control signal.

18. A subscriber station as defined in claim 15, including:

(a) a demodulator for connection to the transmission medium, for converting digital signals carried by the transmission medium to baseband,

(b) a bus system

(c) said data acquisition means including means for receiving the baseband digital signals and applying them to the bus system,

(d) a logical address memory, forming said first memory means, for permanently storing said first address code signal, connected to the bus system,

(e) a random access memory, forming the second memory means, for storing said service code signal as an option table, connected to the bus system,

(f) a random access memory connected in a circuit to the data acquisition circuit and to the bus system for storing said control signals,

(g) input-output circuit means connected to the bus system having a plurality of input and output control ports,

(h) a television signal unscrambler having an input for connection in an input circuit path to the transmission medium, an output for connection in an output circuit path to a display device, and a control input connected to an output control port of the input-output port means,

whereby the unscrambler is enabled upon generation of an unscramble signal by the processor means, applied to the input-output circuit means, under control of said control signal.

19. A subscriber station as defined in claim 18, further including a video display generator connected to the bus system for generating alphanumeric characters and/or pattern signals under control of the processor according to the control signal.

20. A subscriber station as defined in claim 18, further including a video display generator connected to the bus system for generating alphanumeric characters and/or pattern signals under control of the processor according to the control signal, means for receiving input order signals at an input control port, and means for generating further alphanumeric characters and/or pattern signals under control of the processor dependent on the interaction between said order signals and said control signals.

21. A subscriber station as defined in claim 15 in which the controlling means is comprised of a microcomputer.

22. A subscriber station as defined in claim 15 in which the display device is comprised of a printer.

23. A subscriber station as defined in claim 15 in which the controlling means is comprised of a facsimile display apparatus.