Closed circuit television modem sharing system

• US 3,886,302 A
• Filed: 01/28/1974
• Issued: 05/27/1975
• Est. Priority Date: 01/28/1974
• Status: Expired due to Term

• Current Assignee: Thomas J. Kosco
• Original Assignee: Thomas J. Kosco
• Inventors: Kosco, Thomas J.
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Buczinski, S. C.
• Application Number:
  US05/437,410
• Time in Patent Office: 484 Days
• Field of Search: 325/308 178/5.1,DIG.13
• US Class Current: 380/211
• CPC Class Codes: H04N 7/17345 Control of the passage of the selected programme

Abstract

A system for controlling CATV program viewing in a plurality of modes of operation. In a first mode of operation, a downstream digital transmission causes control means to develop first binary data for comparison in a comparator with selected-channel code data from channel means to enable a first circuit to allow a first or second category program to be selected and received by a subscriber during a predetermined temporary period of time. In a second mode of operation the enabling of a second circuit by the subscriber will only cause the control means to be enabled if the subscriber is authorized to receive that selected first category program. In a third mode of operation the enabling of the second circuit by the subscriber will enable a third circuit to allow a selected second category program to be received. In a fourth mode of operation the selection of a third category program by the subscriber will enable a fourth circuit to allow that selected third category program to be received. MODEM sharing networks are provided in the cable system interconnecting a local processing center and the various subscriber terminals. Each MODEM sharing network has modulation and demodulation circuitry, and ability to handle about twelve subscriber terminals.

Claims

1. A subscriber type television system having a central television program gathering and processIng facility, a plurality of subscriber terminals and a cable distribution subsystem linking the facility with the subscriber terminals, the improvement comprising in combination:

at least one MODEM sharing network as an integral portion of the cable subsystem and interposed between said facility and plurality of subscriber terminals for enabling selection of video programs available at the central television program gathering and processing facility servient to the plurality of said terminals, said at least one MODEM sharing network including a data modulator-demodulator for modulation and demodulation of signals communicated in upstream and downstream paths respectively between the subscriber terminals and the facility; and

program control means as an integral portion of said at least one MODEM sharing network for enabling selection of at least one of four modes of operation of said system, said plurality of subscriber terminals each being devoid of capability for enabling selection of said at least one of the four modes of operation of said system and also being devoid of said modulator-demodulator.

2. The invention as stated in claim 1, including:

coaxial cable means for communicating television signals between the MODEM sharing network and the subscriber terminals; and

a telephone transmission line for communicating pulses between the MODEM sharing network and the subscriber terminals.

3. The invention as stated in claim 1, wherein the MODEM sharing network includes:

a data encoder in an upstream path to the facility for encoding data communicated from said terminals;

a data decoder in a downstream path to the terminals for decoding data communicated to said terminals; and

terminal address recognition logic means responsive to signals from said downstream path for ensuring proper communication between the local processing center and any of said terminals.

4. The invention as stated in claim 3, including a filter and combiner circuit responsive to signals communicated between the facility and any of the terminals.

5. The invention as stated in claim 2, wherein each of the terminals comprises:

a time division multiplexer and demultiplexer connected by means of the telephone transmission line to the MODEM sharing network.

6. The invention as stated in claim 4, including television signal switch means responsive to the filter and combiner and to the data decoder for passing the television signals to a preselected number of the subscriber terminals.

7. The invention as stated in claim 1, wherein said system has a plurality of channels for carrying television programs to the subscriber terminals, and wherein said program control means has means for providing at least one of the following modes of operation consisting of:

first means for providing preview enabling commands to the terminals so as to enable any of said terminals to preview any of the programs for a predetermined period of time free of charge;

second means for providing video enable commands to the particular one of the terminals making demand upon any of the programs restricted for viewing by a particular subscriber class and transmitting the restricted program on a pay basis wherever authorized, or inhibiting transmission of the demanded restricted program if unauthorized to receive same;

third means for providing a video enabling command to the particular one of the terminals making demand for transmission of any of the nonrestricted pay programs and billing the demanding subscriber for the channel selected; and

fourth means for providing any of the subscriber terminals access to any of the channels allocated for communication of nonscription television programs for viewing same, free of charge.

8. The invention as stated in claim 7, including:

means for controlling and storing channel enabling data responsive to any one of the first, second and third means so as to enable subscriber switching between the channels carrying the programs purchased without repetition by the subscriber of purchase requests therefor.