GB2283398A

GB2283398A - An interactive television system

Info

Publication number: GB2283398A
Application number: GB9322226A
Authority: GB
Inventors: Mohammed Alam; Abdul Majid Hassan
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-10-28
Filing date: 1993-10-28
Publication date: 1995-05-03
Also published as: GB9322226D0

Abstract

An interactive television system e.g. for hotels comprises a plurality of interface units 11 for connecting audio and/or video signals to a predetermined channel of respective television receivers 10. The interface units 11 are connected via a two-way cable to a control unit 30, 31 having a plurality of signal output channels, each interface unit 11 being arranged to connect an output from the control unit to the input channel of its respective television receiver. The control unit 30, 31 responds to control signals from each interface unit to control respective sources A to E of audio and/or video signals which are connected to the input channel of their respective television receivers 10, e.g. interactive type compact disc players, computers/wordprocessors, video cassette recorders and computer games consoles. <IMAGE>

Description

An Interactive Television System This invention relates to an interactive television system in which the viewer is able to select and control one of a variety of input sources to their television receiver.

Distributed television systems are known which comprise a plurality of subscribers each connected to a cable carrying a large number of television channels. Each subscriber is able to select from any one of these television channels, which may include channels received by a VHF/UHF aerial or satellite dish.

It has been proposed to provide so-called interactive television systems in which the subscriber or viewer is able to select and control the images on their monitor. These systems involve complicated cabling, and thus it is difficult to upgrade conventional cable distributed television systems for interactive use.

We have now devised a interactive television system which can utilise the cables used in conventional distributed television systems.

In accordance with this invention, there is provided an interactive television system comprising a plurality of interface units for connecting audio and/or video signals to a predetermined input channel of respective television receivers, the interface units being connected to a control unit having a plurality of signal output channels, each said interface unit being arranged to connect a said output channel to the input channel of its respective television receiver, the control unit being responsive to control signals from each of the interface units so as to control respective sources of the audio and/or video signals which are connected to the input channel of their respective television receivers.

Thus, each viewer or subscriber is able to receive a channel which they can control, the audio and/or video signals being transmitted to the television receivers using conventional techniques. The control unit may control sources of audio and/or video signals such as interactive type compact disc players (CDI), computers/wordprocessors, video cassette recorders and computer games consoles, each viewer or subscriber being able to select and control one of these sources.

Preferably the interface units are connected to a cable which carries the audio and/or video signals in one direction from the control unit, and which feeds the control signals in the reverse direction to the control unit. The interface units are preferably connected in parallel to the cable.

In one embodiment each television receiver is allocated an output channel from the control unit, the interface units being arranged to connect the input channel of their respective television receivers to their allocated output channel from the control unit, and the control unit being initially responsive to said control signals from each said interface unit to connect a selected source of audio and/or video signals to their respective allocated output channel.

In an alternative embodiment, the control unit outputs a plurality of output channels each carrying audio and/or video signals from separate sources, the interfaces each being arranged to switch a said output channel carrying signals from a selected source to the input channel of its respective television receiver.

Preferably the interface units output their respective control signals to the control units on separate channels.

Alternatively the interface units may output their respective control signals all onto the same channel together with an address signal which enables the control unit to determine the source of the control signals.

Preferably the cable comprises a co-axial cable.

Alternatively the cable may comprise an optical fibre cable.

Preferably each interface unit processes the audio and/or video signals received from the control unit, so that signals on a channel connected to its said television receiver are not fed to the television receiver of another interface unit. Thus, viewers or subscribers are not able to receive signals being sent to other viewers or subscribers.

Preferably the interface units are arranged to feed a plurality of input channels to their respective television receivers, at least one of the channels carrying signals which can be received by all of the receivers. Thus, each of the viewers or subscribers are able to receive at least one general channel, say from an aerial or satellite dish, in addition to the interactive channel over which they have control.

An embodiment of this invention will now be described by way of example only and with reference to the accompanying drawings, in which: FIGURES la and lb together form a block diagram of an interactive television system in accordance with this invention.

Referring to Figure la of the drawings, there is shown an interactive television system comprising a plurality of television receivers 10 having their RF inputs connected to respective interface units 11. Each interface unit 11 has inputs for connecting to control devices such as a keyboard 12, a joystick/pad 13 and a mouse 14. The interface units 11 also have inputs for connecting to monitoring devices such as a motion detector 15, panic button 16 and an air conditioning monitor 17. The interface units 11 are connected in parallel to a co-axial cable 18.

A satellite dish 20 and aerial 21 are connected to respective inputs of a combiner and RF amplifier 23. The output of the combiner/amplifier 23 is connected to a tap 24 which feeds the signals output from the combiner/amplifier 23 in one direction along the co-axial cable 18 to the interface units 11. The tap 24 also feeds signals flowing in the reverse direction on the cable 18 to the control unit of the system via a co-axial cable 22.

Referring to Figure lb, there is shown the control unit for the system, which unit comprises a controller 30 and a signal unit 31. The controller 30 comprises a modulator/demodulator (MODEM) 32, memory 33, a central processing unit (CPU) 34 and an output interface 35. The output interface 35 has outputs connected to a plurality of devices A-E which can be controlled by the viewers or subscribers. These devices may include a computer/ wordprocessor, interactive type compact disc player (CDI), computer games console, video cassette player and management unit. The audio and video outputs of the devices A-E connect to an exchange 36 which is controlled by the CPU 34, and the audio and video output from the exchange is connected to an RF modulator 37. The RF output from the modulator 37 is connected via a co-axial cable 39 to an input of the combiner/amplifier 23.The exchange 36 also has audio and video outputs 38 which may be connected directly to peripheral devices.

In use, the interactive television system defined above may be installed in a hotel, hospital or other location where a plurality of television receivers are connected via co-axial cables to a source of television signals. The satellite dish 20 and aerial 21 receive television signals, which are applied via the combiner/amplifier 23, cable 18 and the interface units 11 to the RF input of each television monitor 10. The television monitor 10 comprises a tuner which demodulates the signals at its RF input, and a memory which can be programmed with tuning data so that the television can be tuned to a desired television channel by entering the program number assigned to that channel.

The system may be configured so that the control unit (Figure lb) outputs a different interactive television channel to each of the television monitors 10. These interactive channels are output from the control system on separate UHF/VHF frequency channels. Thus, the number of frequency channels output corresponds to the number of interface units 11 being served by the system. Each interface unit 11 is arranged to pass its respective interactive channel to its television receiver 10, and to block the interactive channels intended for the other units 11. For convenience, the interface units 11 may remodulate their respective interactive channels onto the same frequency channel.

When a viewer or subscriber tunes his television receiver to the interactive channel he will be presented with a menu listing the option available, e.g.: 1) LASER DISC PLAYER 2) COMPUTER GAMES CONSOLE 3) COMPUTER/WORDPROCESSOR 4) VIDEO CASSETTE RECORDER.

He can select from one of the options by pressing the appropriate number on the keyboard 12. A sub-menu may then be presented e.g. giving a list of the films, computer games or software packages available for that option. Each interface unit 11 comprises an RF modulator which modulates the control signals from the keyboard 12, joystick/pad 13, mouse 14 and monitoring devices 15-17 onto a frequency channel. Each interface unit 11 may output its control signals on a separate frequency channel so that the controller 30 can recognise the source of the control signals. Alternatively, the control signals from the different interface units 11 may be sent all on the same frequency channel but with address codes to identify the source of the signals.

The MODEM 32 of the controller 30 demodulates the transmitted control signals. The demodulated control signals are applied to the memory 33 which determines the source of the signals and the nature of the request being made. This information is then passed to the CPU 34 which outputs signals to control one of the devices A-E. The output interface 35 converts the control signals from the CPU 34 into serial or parallel control signals which can be applied to control the devices A-E.

The video and audio output signals from each of the devices A-E are applied to the exchange 36 which multiplexes the signals into the RF modulator 37. The RF modulator 37 modulates the signals output from the exchange onto the appropriate UHF/VHF frequency channels. The output from the modulator 37 is applied to the co-axial cable 39 which connects to the combiner/amplifier 23.

Thus, if a viewer or subscriber wants to watch a film he can select the film from his on-screen menu. The controller 30 recognises the control signals from his interface unit 11 and selects the appropriate device e.g. A. The output signals from that device are then applied to the frequency channel which is allocated to his interface unit. The film may be stopped, replayed, played in slow-motion etc by sending control signals from the keyboard 12 or mouse 14. The controller may be arranged to record each viewer's or subscriber's use of the system, so that statistics of system usage can be prepared e.g.

for charging purposes.

The system may be used to play computer games, in which case the output from the computer games console device may be switched to two or more frequency channels, so that people in different locations can play against each other.

The viewers or subscribers are able to type letters etc by selecting the wordprocessor option of the computer. The output from the wordprocessor may be directed to a printer or to another viewer or subscriber connected to the system.

Alternatively the viewer or subscriber may wish to use an alternative software package on the computer.

The monitoring devices 15-17 control a management system device e.g. E, so as to operate an intruder alarm, air conditioning or other service. The management system may output video signals, so that the viewer or subscriber can interrogate the system or control and change its operation.

The number of television receivers which may be served by the system is limited by the bandwidth of the co-axial cable. However, the system may be configured so that the control unit outputs signals from each device A-E as separate UHF/VHF frequency channels. Thus, if a viewer or subscriber wants to watch a film, he can select the film from his onscreen menu as before. The controller 30 recognises the control signals from his interface unit 11, and the modem 32 sends control signals back to the interface unit 11 to switch the channel of the selected device to the input of the receiver.

It will be appreciated that the interactive television system is extremely versatile, yet inexpensive and uncomplicated to install. The system may be installed alongside of an existing television system in which viewers or subscribers are connected via co-axial or optical fibre cables to a source of television signals.

Claims

1) An interactive television system comprising a plurality of interface units for connecting audio and/or video signals to a predetermined input channel of respective television receivers, the interface units being connected to a control unit having a plurality of signal output channels, each said interface unit being arranged to connect a said output channel to the input channel of its respective television receiver, the control unit being responsive to control signals from each of the interface units so as to control respective sources of the audio and/or video signals which are connected to the input channel of their respective television receivers.

2) An interactive television system as claimed in claim 1, in which the interface units are connected to a cable which carries the audio and/or video signals in one direction from the control unit, and which feeds the control signals in the reverse direction to the control unit.

3) An interactive television system as claimed in claim 2, in which the interface units are connected in parallel to the cable.

4) An interactive television system as claimed in claim 2 or 3, in which the cable is a co-axial cable.

5) An interactive television system as claimed in claims 2 or 3, in which the cable is an optical fibre cable.

6) An interactive television system as claimed in any preceding claim, in which each television receiver is allocated an output channel from the control unit, each interface unit being arranged to connect the input channel of its respective television receiver to the output channel from the control unit allocated to that television receiver, and the control unit being initially responsive to said control signals from each said interface unit to connect a selected source of audio and/or video signals to their respective allocated output channel.

7) An interactive television system as claimed in any of claims 1 to 5, in which the control unit outputs a plurality of output channels each carrying audio and/or video signals from separate sources, the interfaces each being arranged to switch a said output channel carrying signals from a selected source to the input channel of its respective television receiver.

8) An interactive television system as claimed in any preceding claim, in which the interface units output their respective control signals to the control units on separate channels.

9) An interactive television system as claimed in any of claims 1 to 7, in which the interface units are arranged to output their respective control signals all onto the same channel together with an address signal which enables the control unit to determine the source of the control signals.

10) An interactive television system as claimed in any preceding claim in which each interface unit is arranged to process the audio and/or video signals received from the control unit, so that signals on the input channel of its said input channel are not fed to the television receiver of another interface unit.

11) An interactive television system as claimed in any preceding claim, in which the interface units are arranged to feed a plurality of input channels to their respective television receivers, at least one of the channels carrying signals which can be received by all of the receivers.

12) An interactive television system substantially as herein described with reference to the accompanying drawings.