AU620808B2

AU620808B2 - Distribution apparatus

Info

Publication number: AU620808B2
Application number: AU17558/88A
Authority: AU
Inventors: John William Burden
Original assignee: ZEGUM Pty Ltd
Current assignee: ZEGUM Pty Ltd
Priority date: 1987-06-09
Filing date: 1988-06-09
Publication date: 1992-02-27
Anticipated expiration: 2008-06-09
Also published as: AU1755888A

Description

x4 620808 COMMONWEALTH OF AUSTRALIA Patents Act 1952 4CR4UW-X 3Ei 1 IWJIEM4 (Patent Application No. PI 2361) I I

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C S C, C P-nM1DT :uFPV QDV'TVTf'AqTnW 1UnD 'PUV TIJIFDM'TAMh VMMTTIn.- "DISTRIBUTION APPARATUS" The following statement is a full description of this invention, including the best method of performing it known to us:- 2 This invention relates to audio, video and data distribution apparatus and to methods of distributing electronic data.

This invention has particular but not exclusive application to the distribution,of audio, video and data within passenger compartments of vehicles, and for illustrative purposes reference will be made to such application. However, it is to be understood that this invention could be used in other applicationE, such as the 1O: 0 distribution of audio, video a data within buildings.

Passenger vehicles of all types are now often fitted with systems to distribute information and entertainment to the passengers. A central system aboard the vehicle generates electrical signals from recorded media or by receiving broadcast signals and distributes this information in the form of electrical signals to outlets located near the passenger seats. Passengers are issued with headphones which plug into these outlets so that they may listen to programs without disturbing other passengers. Frequently, a number of 2 programs are distributed simultaneously and each outlet is provided with a selector switch to enable each passenger to ichoose the program which they desire to hear. New vehicle designs incorporate more elaborate distribution systems in which video information is displayed on individual display units near each passenger.

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i L- i lrrr~ -ar 3 The electrical wiring necessary to provide this service can be very complex, and the cost of installing it can be high, particularly when the facility is being added to an existing vehicle. Repairr and maintenance can also be a problem, as the equipment is usually installed within confined spaces.

The present invention aims to alleviate the above disadvantages and to provide distribution means and methods which will be reliable and efficient in use. Other objects 10 and advantages of this invention will hereinafter become apparent.

With the foregoing and other objects in view, this invention in one aspect resides broadly in information distribution apparatus for relaying information signals within a vehicle, said information distribution apparatus including:electrical signal generation means for generating an information signal having a plurality of channels; an information signal antenna from which said information signal is distributed within the vehicle, said information signal antenna being a slotted co-axial cable extending within the vehicle and Sreceiving means for receiving said distributed information signal, said receiving means being a plurality of personally portable wireless signal receivers for receiving said distributed information signal.

Preferably the wireless distribution means is an electromagnetic system such as a radio transmitter, but of course other distribution systems may be used if desired.

For instance, infra-red light systems may be used as a distribution means.

Preferably, a radio distribution system t; rti tr t

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til t, C I r i7 \4A 4 is used and the transmitting antenna is in the form of slotted or "leaky" co-axial cable installed longitudinally within the passenger compartment. Of course other forms of antenna such as pairs of parallel conductors may be used if desired.

Preferably a plurality of generation means is provided, and the generation means may include broadcast programs received by the vehicle, pre-recorded programs replayed on the vehicle, live commentaries or announcements, or paging signals. Selected generation means may include information in foreign languages for tourists. Preferably the encoding means uses frequency modulation, but of course other encoding means such as amplitude modulation may be used if desired.

The generation means may include encoding means for 1 encoding the outputs of a plurality of encoding switches placed in selected locations within the vehicle, whereby the electromagnetic distribution may distribute within the vehicle radiated information related to the location of an actuated encoding switch. The encoding switch may include 2C encoding means and may be connected directly to the transmitting antenna for radiating the output of the encoding means, or may include modulating means whereby the outputs from a plurality of encoding switches may be transmitted in multiplexed form to a common encoding means. Preferably, however, a plurality of encoding switches is wired to a common encoding means, and the latter is programmed to transmit to the transmitting antenna respective encoded signals characteristic of the respective encoding signals.

Reception means may be provided for receiving the signal distributed by the wireless distribution means and decoding or demodulating the signal for the production of audio, video or data information. Preferably the wireless receivers are in the form of headphones incorporating tuning means for I 0 e selecting the desired channel of information and control means for adjusting the sound level of the headphones, although of course standard portable radios may be used if I desired. Special headsets with high output power may be provided for passengers with hearing problems. The use of portable reception and decoding means enables passengers to °1*1 move around within the passenger compartment without interruption to their listening.

The wireless receivers may also include decoding receivers such as remote "pagers" having selective decoding characteristics whereby messages may be transmitted to selected wireless receivers, such as those used by service personnel who may include stewards, hostesses and waiters.

The decoding receivers may include headphones, but preferably the decoding receivers include inbuilt audible warning means and may also include a visual display indicating the nature of a transmitted message. In particular, a transmitted 6 message may be in the form of information related to the location of an encoding switch which has been actuated.

Preferably, if the distribution apparatus is to be used in a vehicle with multiple passenger compartments, the slotted co-axial cables in separate compartments are connected together externally by external connection means in the form of low-leakage co-axial cables. The external connection means may be formed as fixed wiring, but it is preferred that they be detachably attachable, whereby adjacent passenger compartments may be moved apart for purposes such as servicing. The external connection means may be formed as a connection separate from a standard power cable connection assembly. Preferably, however, the external connection means is integrated with the standard power ,1s' connection assembly such that no extra electrical connections I need be made for the distribution apparatus. Booster amplifiers may be added to the system to compensate for losses on long runs of antennae.

In a vehicle having multiple passenger compartments, ?2A a single common encoding means may be provided for a plurality of passenger compartments, but it is preferred that a common encoding means be provided for each passenger compartment having encoding switches, whereby electrical wiring between encoding switches and common encoding means may be simplified, particularly in the case of an articulated 4

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train of passenger carriages, where electrical wiring to a single common encoding means would be required to be detachably attached between the passenger carriages.

In another aspect of this invention, a wireless receiver may draw the power necessary for its operation, as well as the information, from the transmitted signal whereby dependence on batteries internal to the wireless receiver may be reduced or eliminated.

In order that this invention may be more easily 1 understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate r i Ipreferred embodiments of the invention, wherein:- FIG. 1 is a schematic diagram of a single channel distribution apparatus; 15 FIG. 2 is a schematic diagram of a multi-channel t t: distribution apparatus; FIG. 3 is a schematic diagram of the multi-channel distribution apparatus adapted for use in a multiconpartment vehicle such as a train, and 2FIG. 4. is a cross-section of a passenger rail car showing the installed antennae.

In FIG. 1, a transmitting assembly 10 includes a program source 11, a radio-frequency encoder 12 and a transmitting antenna system 13. The transmitting antenna system 13 is enclosed within a vehicle passenger compartment 14 and 1 i4 hy~~P~ transmits to receivers 15 within the vehicle passenger compartment 14.

In use, the transmitting assembly 10 is operated by energising the program source 11. The output from the program source 11 is fed to the input of the radio frequency encoder 12 in which it is used to modulate a radio frequency oscillation generated within the radio frequency encoder 12.

The modulated radio frequency signal passes to the transmitting antenna 13 which radiates an electromagnetic field within the passenger compartment 14 of the vehicle. The radiated power need only be very small because of the short range involved. This signal is received S by receivers 15 within the passenger compartment 14 which are tuned to the frequency of the signal radiated by the transmitting antenna 13.

SAs shown on FIG. 2, a program source assembly a ai includes radio receivers 21 and 22, recorded program players 23 and 24, and public address system 25. Each program source sends its program to a radio frequency encoder 26. The radio frequency encoders 26 encode the programs input to them onto different radio frequencies. A mixer 27 combines the encoded outputs from the radio frequency encoders 26 and feeds the transmitting antenna system 28. The transmitting antenna system 28 is enclosed within a vehicle passenger compartment 29 and transmits to receivers 30 within the vehicle passenger II._ Scompartment 29.

In use, the program source assembly 20 is operated by energising any or all of the program sources 21 to 25. These feed their outputs to the inputs of radio frequency encoders 26 where they are used to modulate radio frequency oscillations generated within the radio frequency encoders 26. All radio frequency encoders operate on different radio frequencies. The outputs of all radio frequency encoders 26 are fed into a mixer 27 which produces a summation of all the input signals at its output. This output is fed to the transmitting antenna system 28 within the passenger compartment 29 of the vehicle and the signal radiated by the transmitting antenna system 28 is received by receivers 30 which can be tuned to select the radio frequency which is modulated by the program source chosen by the listener.

In FIG. 3, a transmitting assembly 30 includes program sources 31, radio frequency encoders 32, and a mixer/buffer amplifier 33. A transmitting antenna 34 in the form of a slotted co-axial cable is connected to the mixer/buffer amplifier 33 and runs the length of the passenger compartment The transmitting antenna 34 terminates in a socket 36 accessible externally to the passenger compartment 35. A socket 37 is attached externally to a second passenger compartment 38 and connected electrically to a further I _Y_~Ln~RI transmitting antenna 39. Sockets 36 and 37 are connected by connecter cables 40 formed from low-loss fully-shielded coaxial cable. The further transmitting antenna 39 passes through the second passenger compartment 38 and is terminated in a socket 41 accessible externally to the second passenger compartment 38. The socket 41 may be used to connect to further passenger compartments through further connecter cables.

Steward call switches 42 and 43 are placed in selected 119, locations along the length of each passenger compartment v- and 38 respectively. The call switches 42 are connected to an encoder 44 associated with passenger compartment 35 which .t produces a switch code characteristic of the location of each of the call switches 42 when it is operated, and which 1' modulates the switch code to produce a steward call signal which is fed to the antenna 34, along with a compartment code t characteristic of the encoder 44. The steward call signal may be received by a pager receiver carried by a steward, the pager producing &n audible alarm to indicate that a call switch has been operated and displaying on an alphanumeric display the encoder identification code and the call switch location code. Similarly, the call switches 43 are connected to an encoder 45 associated with passenger compartment 38.

In use the transmitting assembly 30 is operated by energising the program sources 31 and modulating radio 11 frequency carriers with radio frequency encoders 32. The outputs from the radio frequency encoders 32 are mixed and amplified by the mixer/buffer amplifier 33 before being fed to the transmitting antenna 34 within the passenger compartment 35. The transmitting antenna 34 radiates its signals within the passenger compartment 35. a further transmitting antenna 39 is located within the second passenger compartment 38. It receives its signal from the transmitting antenna 34 through a connection between the I O1do passenger compartment 35 and the second passenger compartment 38 through the connecter cable 40 which is formed of lowloss cable which transmits the signal with minimal external I T radiation. Further passenger compartments may be added to the system by interconnecting the antenna systems within them in series with the abovementioned transmitting antennae. In an installation comprising many passenger compartments, it may be necessary to provide buffer amplifiers at intervals along the antenna system.

If a passenger in compartment 35 desires to call a 0..

7 1O steward to his location, he presses the closest call switch 42, producing an output signal from the encoder 44 in the form of a radio-frequency signal encoded with the identity of the encoder 44 and the call switch 42. The transmitted signal may be received by a pager receiver carried by a steward, and the pager may display a code characteristic of 1 i the location of the call switch 42, enabling the steward to determine the location at which his services are required.

In FIG. 4, the passenger compartment 50 of the vehicle 51 contains passenger seats 52 and luggage racks 53. The transmitting antenna 54 in the form of a slotted co-axial cable mounted between a non-conducting false ceiling 55 and the conductive roof of the passenger compartment 56.

It will of course be realised that while the above has been given by way of illustrative example of this invention, 0. all such and other modifications and variations thereto as O 0 would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein defined in the appended claims.

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Claims

2. Information distribution apparatus as claimed in claim i, wherein said electrical signal generation means includes a radio transmitter.
3. Information distribution apparatus as claimed in claim 1 or claim 2, wherein said information signal antenna is a linear antenna disposed longitudinally within said vehicle.
4. Information distribution apparatus as claimed in any one of claims 1 to 3, wherein said electrical signal generation means includes playback apparatus for pre-recorded 14 information. Information distribution apparatus as claimed in any one of claims 1 to 4, wherein said electrical signal generation means includes radio reception apparatus for receiving radio signals transmitted externally of said vehicle.
6. Information distribution apparatus as claimed in any one of claims 1 to 3, wherein said electrical signal generation t means includes a plurality of encoding switches and encoding ttl means for said encoding switches for producing electrical signals characteristic of respective encoding switches. .I 7. Information distribution apparatus as claimed in any one of claims 1 to 6, wherein said vehicle is the passenger compartment of a vehicle. itt 4 8. Information distribution apparatus as claimed in claim 7, wherein said passenger compartment constitutes one of a plurality of passenger compartments. L 9. Information distribution apparatus as claimed in claim 8, wherein selected passenger compartments include respective pluralities of encoding switches and respective encoding means. Information distribution apparatus as claimed in any one Z -G is W -VY C-' of claims 7 to 9, wherein selected passenger compartments are joined external of said passenger compartments by detachably attachable shielded information signal antenna. ii. Information distribution apparatus as claimed in any one of claims 2 to 10, wherein said wireless signal receivers transform a selected one of said signal channels into audio, video and/or data output.
12. Information distribution apparatus as claimed in Claim i i11, wherein said reception means includes a headphone-like I audio receiver for receiving the output from selected one of said information signals.
13. Information distribution apparatus as claimed in Claim 11, wherein said reception means includes a portable paging o: device for receiving the output from selected encoding means. I o
14. A method of distributing information within a vehicle including:- providing information distribution apparatus for relaying information signals within a vehicle, said information distribution apparatus including electrical signal generation means for generating an information signal having a plurality of signal channels; an information signal antenna extending within the vehicle from which said information signal is distributed, said information signal I !I ~IT~ 16 antenna being a slotted co-axial cable; providing receiving means for receiving said distributed information signal, said receiving means being a plurality of personally portable wireless signal receivers for receiving said distributed information signal and transforming said output into audio, video or data output, and operating said information distribution apparatus and said reception means whereby information is transferred from isaid information signal antenna to said reception means within the vehicle. i *I I t Information distribution apparatus susbstantially as hereinbefore described with reference to the accompanying drawings. t 4 I t DATED THIS eleventh DAY OF December, 1991. ZEGUM PTY LTD BY PIZZEY AND COMPANY PATENT ATTORNEYS -'i O o