DISPLAYING DATA TRANSMITTED BY RADIO

Abstract: A display system comprises a display apparatus such as an electronic notice board (36), TV set (46) or computer monitor. Radio messages are received by a point-to-point receiving apparatus (16), such as a wide area digital pager, adjustably mounted on the display apparatus. The receiving apparatus (16) generates non-electrical signals which are transmitted to the display apparatus, the display apparatus having means (40, 41, 42) enabling the signals to be displayed. The receiving apparatus (16) is adjusted to minimise the reduction in the quality of the radio signal received by said receiving apparatus.

Description: DESCRIPTION DISPLAYING DATA TRANSMITTED BY RADIO Technical Field The present invention relates to the displaying of data transmitted by radio and particularly but not exclusively to updating stored data by means of radio transmission. Background Art In applications such as electronic notice boards it is frequently required to update the information displayed. The updating can be done by transmissions through landlines from a central station, which has the disadvantage that the electronic notice board cannot be readily moved around. Alternatively the user equipment may incorporate a dedicated radio receiver which is hard wired into the electronic notice board and any updating is done by way of a radio transmission. Such an equipment is disclosed in British Patent Specification GB 2 247 332 A. Building a radio receiver into the electronic notice board or other end user equipment has a number of drawbacks in that the positioning of the equipment has to be a compromise between viewability and the best possible reception of radio signals and also any equipment containing a radio receiver has to be submitted for type approval by the Radio Regulatory Authorities. Individual type approval is necessary because, amongst other things, an electrically conductive link between the radio receiver and the end user equipment may affect the r.f. properties of the radio receiver. The consequence of this is that a manufacturer of equipment will be reluctant to have too many models because of the time and cost of obtaining type approval. Disclosure of Invention An object of the present invention is to convey data messages to a display apparatus without the necessity for the receiving equipment to be type approved each time. According to a first aspect of the present invention there is provided a display system comprising a radio-less visual display unit, means for semi¬ permanently adjustably affixing a radio apparatus to said display unit so that said radio apparatus may be oriented to substantially best receive a radio signal, said orientation of said radio apparatus being substantially independent of a current orientation of said display unit, and means for receiving an optical radiation signal transmitted from said radio apparatus. The present invention also provides a display system comprising a visual display apparatus which does not require radio-type approval as a pager, means for receiving a non-electrical signal from a radio apparatus for display on said display apparatus, and means for adjustably mounting the radio apparatus so that said display apparatus may be positioned for maximum desired viewability with at most a minimal error rate in the signal receivable at the location of said display apparatus. The present invention further provides a display system comprising a visual display apparatus which does not require radio-type approval as a pager, a point-to-point radio receiving apparatus having means for producing a non-electrical signal corresponding to a signal received by said receiving apparatus, and means for semi-permanently affixing said radio receiving apparatus to said display apparatus so that said display apparatus may be positioned for maximum desired viewability with a minimum achievable reduction in the quality of the radio signal received by said receiving apparatus at the location of said display apparatus. In accordance with the present invention the point-to-point receiving apparatus is a self contained unit which is physically independent of the visual display apparatus, which may comprise a TV set, a monitor of a personal computer, electronic notice board or other information display/or storage device. By using a visible/non-visible radiation link, the r.f. properties of the radio receiving means are not altered and in consequence it is the only part of the system which requires type approval so that a single type approved radio receiving apparatus can be used with any number of end user equipments without the need to seek separate type approval for each user apparatus. The radio receiving apparatus may comprise for example, a message pager with or without its own memory. The receiving apparatus may be mounted in the best position for receiving signals from a central station. The link from the receiving means to storage means in the user apparatus may comprise a light emitting diode in the receiver which is coupled to the storage means by an optical fibre which is terminated by a suitable decoder to convert optical signals into electrical signals suitable for storage. Alternatively the receiving means may be equipped with an infra-red emitter and the storage means with an infra-red receiver. Such an arrangement offers great flexibility in the relative positioning of the receiving means and the storage means, especially when incorporated in an end user device. The positioning of the radio receiving apparatus may be determined by minimising the error rate in the received signal. It is known from Japanese published patent application 59-169237 to provide two-way data transfer between a portable terminal and a data transmitter by means of optical couplings. Both the portable terminal and the data transmitter have a photodetector and a light emitting diode. The portable terminal is received in a recess in the data transmitter, and the data transmitter's photodetector and LED are disposed opposite the portable terminals LED and photodetector, respectively. There is no disclosure of relaying data via a radio frequency link and physically separating the data terminal from the data transmitter. European Patent Specification 0 232 123 discloses a radio pager in which calling address signals together with time signals are stored by the pager in a random access memory. In response to a manual command signal the contents of a memory are read out and supplied to a light emitting device. More particularly, in order to print out the stored address signals, a photodetector is juxtaposed with the light emitter, the photodetector being connected to the printer. In order to provide the necessary juxtapositioning of the light emitter and photodetector, the printer has a light shield and the pager is inserted into the light shield in order to effect the optical coupling between the light emitter and the photodetector. There is no suggestion in that publication of address and time signals being printed out as they are received. European Patent Specification 0426 966 discloses the use of a pager with a separate TV set for additional message display. The pager may relay message data to the TV set by way of a bi-directional infra red link or an electrical communication cable coupled to the pager and the TV set. The use of an infra-red link means that the pager and TV set have to be arranged to provide a line of sight path which means that the pager may not be optimally positioned with respect to the reception of radio messages. Using an electrical communication cable has the drawback of desensitizing the receiver. Brief Description of Drawings The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a block schematic diagram of one embodiment of the invention, Figure 2 is a diagram illustrating the mounting of a pager on the housing of a tv set (or monitor), and Figure 3 is a diagram illustrating the mounting of a pager in a remote controller. In the drawings the same reference numerals have been used to indicate corresponding features. Modes for Carrying Out the Invention Figure 1 illustrates a digital paging system comprising a base station 10 including a processor 12 for formatting address and message data to be transmitted by a transmitter 14. Any suitable address and message format can be used for example the CCIR Radiopaging Code No. 1 , otherwise 5 known as POCSAG (Post Office Code Standardisation Advisory Group). Details of this radiopaging code are given in a book entitled "The book of the CCIR Radiopaging Code No. 1" published by the Radiopaging Code Standards Group (RCSG) in 1986. Appendix 1 discloses the Specification for a standard Code Format for use in Wide Area Radiopaging Systems the details of which will be known by those skilled in the art. However for the sake of completeness the signal format used comprises a batch structure consisting of preamble and a succession of concatenated batches. Each batch consists of a synchronisation codeword plus 8 frames each comprising 2 codewords, making a total of 17 codewords. There are two types of codewords, address codewords and message codewords, each comprising 32 bits. In the case of a message codeword 20 bits form a data field. Bits 20 and 21 of an address codeword are function bits and are used to select the format of decoding of concatenated message codewords. Appendix 1 , subsection 4.1 states that for the sole transmission of messages in decimal numbers, 4 bits per character are used and the function bits are set to 00. Subsection 4.2 refers to an Alpha-numeric or General Data Format and states that the ISO 7-bit coded character set is used and that the function bits are set to 11. When sending a message, the batch structure is maintained. Thus a message comprises an address codeword and concatenated message codewords plus a synchronisation codeword at the beginning of each batch. The illustrated system further comprises a point-to-point radio apparatus such as a pager 16 which may be either a modified tone only pager or numeric or alphanumeric message pager. The pager 16 comprises a radio frequency receiver 18 which is tuned (or tunable) to receive the address and message data transmitted by the base station 10. The receiver 18 is periodically energised to receive the synchronisation codeword in each batch and to be able to receive any address codewords transmitted in its predetermined frame and any concatenated message codewords. The receiver 18 has an output to a decoding stage 20 which includes means for error detection and correction within the limits possible by the radiopaging code used. The decoding stage 20 checks addresses transmitted in the appropriate frame for data transmitted to the particular pager. If a match is detected between the transmitted data and an internally stored address then the paging receiver 18 remains energised so that the concatenated message data codewords appear at the output of the stage 20, which output is connected to a microcontroller 22. A keypad 24 and alerting devices comprising a vibrator 26, acoustic transducer 28 and light emitting device, such as an LED 30, are connected to the microcontroller 22. The microcontroller 22 is connected to the microcontroller 22. The microcontroller 22 is arranged to supply suitably encoded data codewords to the LED 30 substantially contemporaneously with their receipt by the receiver 18, subject to signal processing delays. If the pager 16 is a message pager then a RAM 32 for storing message data is connected to the control 22 together with a LCD panel with associated drivers 34. Thus message codewords from the decoding stage 20 are supplied as a stream of, for example, ISO 7-bit characters to the RAM 32 by the controller 22. When a user wishes to display the message data he actuates the keypad 24 to cause the controller 22 to supply the ISO 7 bit characters to the LCD drivers 34 for display on the panel. A separate user equipment such as an electronic notice board 36 is optically coupled to the LED 30 by a suitably terminated optical fibre 38. The optical fibre 38 is connected to a RS 232 converter 40 which includes a light detector and a signal processor for converting received binary coded optical signals into electrical signals. A RAM 41 is coupled to the converter 40 for storing decoded data signals. Display driver circuitry 42 has an input coupled to an output of the converter 40 and an output coupled to the display device 44. In operation of the electronic notice board 36, display data is stored in its RAM 41. However, if the data is to be updated either on an individual basis or a group basis, then this is done by transmitting a message paging signal from the base station using an individual RIC or a group address RIC. A pager recognising its RIC remains energised to receive the message codewords, which are decoded and relayed to the microcontroller 22. It passes the codewords, if required re-encoded as ISO 7-bit characters, to the LED 30 which is energised in accordance with the binary coding of the message data so as to produce an optical signal version of this data. The optical signal is relayed by way of the optical fibre 38 to the RS 232 converter 40, which converts it to an electrical signal suitable for storage in the RAM 41. In the case of the pager 16 being a message pager, then optionally any message data can be stored in the RAM 32 for subsequent transfer to the LED 30 and onward transmission to the driver circuitry 42. In order to adjust the mounting of the pager 16 for the best reception of radio signals a tiltable and rotational mounting means 50 is provided. The means 50 comprises a base member 52 attached to the top (or side) of the electronic notice board 36. A two-part universal joint type of mounting means is provided at the opposite end of the base member 52. The universal joint shown in Figure 1 comprises a part-spherical cup 58 attached to the base member 52 and a ball 60 which is a friction fit in the cup 58. A mounting bracket 62 is attached to the ball 60 so as to be moveable therewith. Other known types of universal joint type of mounting means may be used including providing a clamping device on the base member 52 which can be used to clamp a ball when the optimum position of the pager has been determined. The mounting bracket 62, which may comprise a light-tight box, has a socket 64 for receiving one end of an optical fibre 38, the other end of which is coupled to the converter 40. In setting-up the display arrangement the pager 16 is placed in the mounting bracket 62 so that the LED 30 is aligned with the socket 52. The mounting bracket 62 is adjusted by way of the universal joint, to obtain an acceptable, if not optimum, angular position for the pager 16 to receive paging signals. One method by which the user can determine an acceptable angular position for the pager 16 is for the pager decoder 20 to measure the error rate in the decoded signal and for the controller 22 to send the error rate to be displayed on the display device 44. The mounting bracket 62 carrying the pager 16 is then adjusted until the error rate is zero or has a minimum value. Since all pagers operating in accordance with the POCSAG protocol are energised to receive the sync codewords, the error check can be done on the sync codewords. Once an acceptable position has been found, further adjustment is unnecessary. Figure 2 shows a display arrangement for use with an alternative display unit such as a TV set 46 (or computer monitor). With such an arrangement a user may carry the pager with them when away from home or office but on return the pager can be coupled to the display unit for displaying not only paging messages but also additional information, such as local news, which may be transmitted by a local radio company to subscribers. Referring to Figure 2, the TV set (or computer type monitor) 46 may be controlled manually or by an infra-red remote controller 48. The means 50 for detachably mounting a pager 16 is similar in many respects to that shown in Figure 1 but the base member 52 includes a suction cup for attaching the member 52 semi-permanently to the top or side surface of the TV set 46. As the remainder of the mounting arrangement is similar to that shown in Figure 1 , in the interests of brevity it will not be described again. In use a user places his/her pager 16 in the mounting bracket 62 so that the LED 30 (Figure 1) is aligned with the socket 52 and switches-on the TV set 46. The user then adjusts the mounting bracket 62, by way of the universal joint, to obtain an acceptable, if not optimum, angular position for the pager 16 to receive paging signals. One method of determining an acceptable position is by measuring the error rate, as described with reference to Figure 1. By suitably adapting the pager 16 and the TV set 46, the pager can derive its electrical power from the TV set. Also paging signals derived from the TV set's antenna may be supplied to the pager. However, such options are not always possible with pagers because their small physical size can limit the number of extra external electrical connections which can be provided. 9 Figure 3 illustrates another variant in which a TV set remote controller 48 is adapted to receive the pager 16 and for data messages to be transmitted to a detector 70 on the TV set by way of an infra-red link. The data messages are stored in a RAM (not shown) for subsequent display. The signal coupling of the pager 16 to the circuitry of the remote controller 48 being by way of an optical link, for example an optical fibre 38. The display panel of the pager 16, if visible, or of the remote control unit can be used to display the error rate but otherwise it can be displayed on screen as described with reference to Figure 2. Although not shown a mouse of a personal computer can be adapted in this way to enable pager messages to be displayed on the monitor screen. In the described and illustrated embodiments since the pager 16 is not electrically connected to the electronic notice board, TV set or other display device then one or two type approved pagers can be used with a large variety of electric notice boards or other display devices. The pager 16 can be positioned for the optimum reception of radio signals and can be separate from other sources of radio interference. Although in the described embodiment light in the visible part of the spectrum is produced by the LED 30, other emitters, such as infra red emitters, may be used with appropriate detectors, for example, as used in television remote controllers. Although the pager has been shown mounted externally of the display apparatus, it is also possible for it to be mounted internally of the display apparatus, particularly when the apparatus includes a cathode ray tube having plenty of unused space around the tube neck. In such an arrangement the optical fibre 38 may be omitted and a light sensor is juxtaposed in a light tight manner with the light emitter of the pager 16. From reading the present disclosure, other modifications and variations will be apparent to persons skilled in the art. Such modifications and variations may involve equivalent features and other features which are already known in the design, manufacture and use of information transmission systems and devices and component parts thereof and which may be used instead of or in addition to features already disclosed herein. Industrial Applicability Display apparatus which can be updated by transmitting suitable radio messages.

Claims: CLAIMS 1. A display system comprising a radio-less visual display unit, means for semi-permanently adjustably affixing a radio apparatus to said display unit so that said radio apparatus may be oriented to substantially best receive a radio signal, said orientation of said radio apparatus being substantially independent of a current orientation of said display unit, and means for receiving an optical radiation signal transmitted from said radio apparatus. 2. A system as claimed in Claim 1 , characterised in that the radio apparatus comprises means for measuring the error rate in a received signal and for transmitting the error rate as an optical radiation signal, whereby said display unit displays the error rate and the radio apparatus is oriented to minimise the error rate. 3. A system as claimed in Claim 2, characterised in that said display unit comprises signal storage means for storing an electrical version of the optical radiation signal. 4. A system as claimed in Claim 1, characterised by an optical fibre coupling an output of the radio apparatus to an input of the display unit. 5. A display system comprising a visual display apparatus which does not require radio-type approval as a pager, means for receiving a non¬ electrical signal from a radio apparatus for display on said display apparatus, and means for adjustably mounting the radio apparatus so that said display apparatus may be positioned for maximum desired viewability with at most a minimal error rate in the signal receivable at the location of said display apparatus. 6. A display system as claimed in Claim 5, characterised in that the display apparatus comprises a TV set and a remote controller for the TV set, and in that the radio apparatus is located in said remote controller. 7. A display system comprising a visual display apparatus which does not require radio-type approval as a pager, a point-to-point radio receiving apparatus having means for producing a non-electrical signal corresponding to a signal received by said receiving apparatus, and means for semi-permanently affixing said radio receiving apparatus to said display apparatus so that said display apparatus may be positioned for maximum desired viewability with a minimum achievable reduction in the quality of the radio signal received by said receiving apparatus at the location of said display apparatus. 8. A display system as claimed in Claim 7, characterised in that the radio receiving apparatus comprises means for measuring the error rate in a received signal and for transmitting the error rate as a non-electrical signal, whereby said display unit displays the error rate and the radio apparatus is oriented to minimise the error rate. 9. A system as claimed in Claim 8, characterised in that said display unit comprises signal storage means for storing an electrical version of the non-electrical signal. 10. A system as claimed in Claim 9, characterised in that the non- electrical signal is an optical signal and in that an optical fibre is provided coupling an output of the radio receiving apparatus to an input of the display unit.

Inventors: MCPERSHON ANDREW DAVID, SHARPE ANTHONY KEITH, MCPERSHON, ANDREW, DAVID, SHARPE, ANTHONY, KEITH
Applicants: PHILIPS ELECTRONICS NV, PHILIPS NORDEN AB, PHILIPS ELECTRONICS N.V.
Application year: 1997
Main classification: G08B5
IPC codes: G08B5, H04B1, H04B10