GB2378874A

GB2378874A - Audiovisual distribution system

Info

Publication number: GB2378874A
Application number: GB0110513A
Authority: GB
Inventors: Frank Ainscow
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-04-30
Filing date: 2001-04-30
Publication date: 2003-02-19
Also published as: GB0110513D0

Abstract

This invention provides for the distribution of audio and video programme material amongst a number of locations within a building, or other environment such as a vehicle, to enable entertainment, communication and other facilities to be used at those locations without limitation by the siting of the primary equipment. The system comprises fixed cabling 1 of standard type, e.g. category 5, local cables which connect individual items of equipment to outlets of the fixed cabling and a central switching point at which the cables are linked together. Linking may be performed manually using a patch panel 2 or automatically under remote control by users. There is provision for users to control the operation of remote equipment using a control channel in the distribution system.

Description

Audiovisual Distribution System This invention provides for the distribution of audio and video programme material amongst a number of locations within a building, or other environment such as a vehicle, to enable entertainment, communication and other facilities to be used at those locations without limitation by the siting of the primary equipment Definition of terms.

In this specification, the following terms are defined: Programme material-sound and/or images conveyed electronically for purposes of entertainment, communication, security etc.

Programme source-a device which derives programme material from some other source, such as a broadcast, a camera/microphone or a recording.

Delivery device-a device which converts programme material from electronic form into human-usable form, i. e. images and sound.

Electronic communication and entertainment equipment is now commonplace in homes and offices. Most such equipment is self-contained and delivers audio and video information at its own location only. Where the material is required at several locations, it is usually necessary to duplicate the equipment at each place, which may be costly and inconvenient.

It would be desirable to allow the audio and video programme material created by a programme source at one location in an environment to be distributed, under user control, to other locations, while allowing the user at the destination location to control the originating programme source by means of its native remote control features. To facilitate the use of the system, it should be compatible with a wide variety of standard appliances, including television receivers and hi-fi systems, requiring no modification of the appliance for connection to the system. Further, the communication medium should be a standard cable type which can be shared with other forms of information distribution such as a computer network, security systems or telephone extensions According to the present invention, there is provided an audiovisual distribution system in which audio and video signals are carried from a source point to one or more destination point (s) by means of standard cabling, the connections between sources and destinations being modifiable from time to time to allow each destination to receive different material at different times.

To facilitate understanding of the invention, its essential features are described in more detail.

The audiovisual distribution system comprises three components: installed cabling, which is generally permanently attached to the environment, a central switching point or system centre, and local cables which are used to connect individual appliances to the installed cabling.

Under this system, the environment is equipped with cables connecting each point of connection to a central switching location-the system centre-where the cables may be linked from time to time to provide a through connection between source and delivery point. Each cable is capable of carrying up to four simultaneous analogue signal channels, of which one has sufficient bandwidth to carry a video signal. Two channels may carry stereophonic sound signals, and the fourth is available to carry control information in the reverse direction, from the delivery location to the source. An example of suitable cable is standard category 5 four-pair cable, but others are also possible, including coaxial or fibre-optic cable with suitable modulation equipment.

The installed cable may be contained within the fabric of the building or laid on the surface. In either case, it is terminated at the distributed connection points in standard, possibly wall-mounted, sockets, for example RJ45 as used in Ethernet I OBaseT systems.

Local connection of the source and delivery equipment is by means of local cables pluggable at one end into the wall socket and at the other end into the standard appliance connectors-typically Scart or multiple RCA-Phono sockets. Adaptation of the appliances to the system is done by choosing an appropriate cable. In some options, the local cable may include an infrared receiver or emitter to provide communication of control signals to a source appliance or from a remote controller located near the delivery device.

The system centre may take various forms, having always the function of linking together pairs or groups of cables. In a simple implementation of the system, the links may be made manually by plugging patchcords into a patch panel located at the system centre. In a more complex implementation, the links are made electronically by means of a switching device which is controlled from the programme delivery points using the same control channel that carries control information from the user to the source.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which :- Figure I shows a possible implementation of the system centre. In this example, the installed cables I are terminated at the system centre in a patch panel 2 and the individual cables are linked by patchcords 3 to the inputs and outputs of a switching device 4. Also in this example, an Ethernet hub 5 is shown connected to other cables in the patch panel, to illustrate the sharing of the cable installation by other services.

Figure 2 shows the local connections at the source and destination locations. In example a), a programme source device 6 is connected by local cable 7 to a wall socket 8 and thence through the installed cable to the system centre. In example b), the signals delivered from the system centre to another wall socket 8 are carried by a different form of local cable 9 to delivery device 10. All connections to the wall sockets are by RJ45 connectors. Local cable 7 carries at the device end three RCA-Phono connectors through which to connect with the source appliance, and also incorporates an infrared emitter 12 by means of which control signals are applied to source device 6 to control its operation. Local cable 9 carries a Scart connector 13 and an infrared receiver 14 by means of which control signals are captured from a remote controller 15 and relayed via the system centre to the connected source device.

Figure 3 shows a schematic representation of the internal structure of the switching device.

In this example, incoming signals carried from source devices by the cables are applied to the input connectors 16 of the switching device 17. The central switching function is carried out by one or more semiconductor AN switching devices 18 operated by a microcontroller 19 using a standard control interface 20. The selected signals are presented at output connectors 21 for transmission through the cables to the selected destinations.

Again in this example, the volume setting at each output is controllable and set to a default level for each input device, to prevent sudden changes of volume on switching channels. Generally this is independent of the volume control at the delivery point Incoming infrared control signals in the back channels arrive from the destination locations at the output connectors 21 and are received by infrared receiver 22 for decoding by the micorcontroller 19. Where appropriate, these signals are relayed to infrared transmitter 23 for onward tranmission to the controlled source devices.

Otherwise, the signals are treated as commands and influence the operation of the switching device.

An on-screen text generator 24 is incorporated to enhance the ergonomic behaviour of the system by providing feedback to the user of the state of the system and the response to his command actions. The text is treated as a video input and switched by the operation of the AN switches 18 to the output currently using it.

In this example, a video signal detector 25 is provided to allow the microcontroller 19 to determine the operational state of a video source connected at any of the inputs 16.

Claims

1. An audiovisual distribution system in which audio and video signals are carried from a source point to one or more destination point (s) by means of standard cabling, the connections between sources and destinations being modifiable from time to time to allow each destination to receive different material at different times.

2. An audiovisual distribution system as claimed in Claim I wherein the audio and video signals are transmitted at baseband using separate wire pairs in a standard cabling system such as category 5 with RJ45 connectors.

3. An audiovisual distribution system as claimed in Claim I or Claim 2 wherein a back channel is used to carry remote control information from the destination point to the source point to allow control of the source equipment by a user located at the destination point

4. An audiovisual distribution system as claimed in Claim 3 wherein connections between sources and destinations are made and broken by means of an electronic switching device which operates under the control of users located at the destination points.

5. An audiovisual distribution system substantially as described herein with reference to figures I-3 of the accompanying drawing.