GB2253291A

GB2253291A - Signalling apparatus

Info

Publication number: GB2253291A
Application number: GB9117230A
Authority: GB
Inventors: Kevin Bell; Martin Ward
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-02-26
Filing date: 1991-08-09
Publication date: 1992-09-02
Anticipated expiration: 2011-08-09
Also published as: GB9117230D0; GB2253291B

Abstract

A signalling apparatus comprises an operator unit (10) and a responder unit (11), each of the operator and responder units (10, 11) comprising means to transmit and receive data signals from one to the other, each of the operator (10) and responder units (11) being adapted to verify that any data signal received thereby, is that which is expected by the unit, one of the responder and operator units (11) when data signal exchange between the operator and responder units (10, 11) is completed, actuating an actuating means (25) to enable an operating function to be performed. <IMAGE>

Description

Title: "Signalling apparatus" Description of the Invention This invention relates to a signalling apparatus and more particularly but not exclusively to a signalling apparatus in which infrared signals can be transmitted from one unit to another to provide remote control over an operating function.

For example, the operating function may be the actuation of a lock of a door of a vehicle or a building, or the arming/disarming of an alarm, or the closing or opening of a valve or switch,or the operation of a motor, or any other function desired.

An Infrared signalling device is known from GB 2192665 which has an operating unit comprising an infrared transmitter and receiver and a responder unit comprising a transmitter and receiver, the transmitter and receiver units being arranged to transmit and recognise respectively, a particular coded infrared signal, and the responder unit when recognising a correct coded signal, actuating an actuator means so that the operating function can be performed.

Although such signalling devices do provide a degree of security it is possible for an unauthorised person to decipher the code of the infrared signal which the responder unit recognises.

According to one aspect of the invention we provide a signalling apparatus comprising an operator unit and a responder unit, each of the operator and responder units comprising means to transmit and receive data signals from one to the other, each of the operator and responder units being adapted to verify that any data signal received thereby is that which is expected from the other unit, one of the operator and the responder units, when valid data signal exchange between the operator and responder units is completed, actuating an actuating means to enable an operating function to be performed.

Thus a signalling apparatus in accordance with the present invention provides for greater security than known signalling devices because of the requirement for an exchange of data signals between the operator and responder units which data signals are each verified by the receiving unit.

The invention is particularly suited to an apparatus in which the signals transmitted between the operator and responder units are infrared signals, although other types of signals such as radio, ultrasonic, etc. could be used.

The invention will now be described with reference to the accompanying drawings in which: FIGURE 1 is a purely illustrative view of a signalling apparatus in accordance with the invention; FIGURE 2 is an illustrative diagram showing the operation of the signalling apparatus of Figure 1.

Referring to the drawings there is shown a signalling apparatus comprising an operator unit 10 and a responder unit 11. The operator unit 10 is small, light and fully portable having its own internal battery power supply, whereas the responder unit 11 is mounted, in this example in a door, and may be arranged to be powered from the mains via a suitable in-built, or exteriorly located transformer, preferably with a battery back up, or solelv by battery.

The operator unit 10 is transportable in much the same manner as a key, and is used when operated, by an operator pressing an actuator button 14 which causes an infrared initial signal to be transmitted as indicated by beam B.

To show to an operator that the operator unit 10 is working, a light emitting diode 15 may be arranged to flash or an audible signal emitted when button 14 is depressed.

The responder unit 11 controls the operation of a lock of the door 12 and prevents the door 12 being opened in its jamb 16 until the lock is released by the responder unit 11.

Referring now also to Figure 2, until the responder unit 11 is initially signalled by the operator unit 10, the responder unit 11 will be in a quiescent mode, using minimal power. The responder unit 11 is preferably arranged automatically to return to this quiescent mode a preset time after the responder unit 11 has been signalled to operate the lock.

When the operator unit 10 is operated, an initial signal I will be transmitted from the operator unit 10 to the responder unit 11, the initial signal I comprising a coded infrared signal. The signal I will be received by a sensor means of the responder unit 11, which, upon recognising the signal, will switch to a responsive mode.

The initial signal I or a subsequent signal sent to the responder unit 11, contains information about data subsequently to be transmitted as well as for example information, such as an operator identification number, about the operator unit 10. In the present case, the operator unit 10, contains in a memory 20 a plurality of sets of data A-F, one of which (B) will be chosen for transmission to the responder unit 11 during subsequent data exchange. The initial signal I includes the information (B) to inform the responder unit 11 to expect to receive data from set B.

The responder unit 11, in response to the initial signal I transmits an initial response signal RI back to the operator unit 10. The initial response signal RI also comprises a coded infrared signal, which is preferably different from the initial signal I which caused the responder unit 11 to switch to a responsive mode.

In this example, the initial response signal RI contains information (D) about data subsequently to be transmitted. Alternatively, information (D) may be contained in a subsequent response signal and any responder identification information e.g. number, may be included. The responder unit 11, like the operator unit 10, contains a memory 21 which has the plurality of sets of data A F, one of which (D) is transmitted to the operator unit during the subsequent data exchange.

The initial signal RI from the responder unit 11, includes the information (D) to inform the responder unit to expect data from set D.

The operator unit 10 may randomly select which of the sets of data A F in memory 20 will be sent to the responder unit 11, prior to transmitting the initial signal I. Similarly, upon being switched to a responsive state, the responder unit 11 may randomly select which of the sets of data A-F in its memory 21 will be sent to the operator unit 10.

Upon receiving the initial response signal RI. the operator unit 10 transmits a first data signal B(J) which may again be a coded infrared signal, the data in the signal B(J) being, as an example, element J from set B.

The responder unit 11 receives the first data signal B(J) from the operator unit 10 and verifies that the signal contains the first data element J the responder unit 11 is expecting to receive from the operator unit 10.

Upon such verification check being successful, the responder unit 11 transmits its own first data signal D(I) to the operator unit 10, which in turn verifies that the signal D(I) received contains the data element I which it is expecting to receive from the responder unit 11.

This data exchange can be arranged to continue for as many times as required. However each transmitted data signal is verified bv the unit 10 or 11 before the next data signal is transmitted from the respective unit 10, 11.

Where any one data signal from either the operator 10 or responder units 11 fails verification e.g. through transmission errors rather than data errors, the apparatus may be arranged for the receiving unit to prompt the transmitting unit, to retransmit the data signal before data exchange continues or the actuating means is activated.

In this example, the data set D contains the data elements "I" "A" "N" "S" and the data set B, the data elements "J" "O" "H" "N", the elements each being transmitted one at a time so that each data element is verified, one at a time. The data sets A-F may contain any alpha-numeric character, or indeed any character of an ASCII keyboard, and the data exchange may involve the exchange of many more data elements from many more data sets than indicated in this example.

If at any time verification fails, data exchange may cease until the operator unit 10 is reactivated, to issue a new initial signal I, so that data exchange takes place from the beginning of the sequence.

Preferably however, in the event that verification fails, for example, if the responder unit 11 receives a data signal which it is not expecting to receive, the responder unit 11 transmits a false data signal for example from a dummy memory set X.

The false data signal preferably appears to be a legitimate data signal although the responder unit 11 will not activate any actuating means, even if a legitimate data signal is subsequently received, until the responder unit 11 again receives an initial signal I from the operator unit 10 containing information about which of the sets of data A-F will subsequently be sent.

Similarly, if the operator unit 10 receives an unexpected data signal, the operator unit 10 transmits a false data signal from a dummy memory set X.

Thus each of the operator and responder units 10,11, will respond to data signals which fail verification in just the same way that thev would respond to expected data signals, but by transmitting false data signals in response. Thus anyone attempting to open the lock of door 12 without a correct operator unit 10, would appear to be succeeding in exchanging data with the responder unit 11, although at the end of data exchange, the lock of door 12 would not be opened by the responder unit 11.

When data exchange between units 10,11, is complete, the units may issue an acknowledgement signal to the other unit.

When a correct and properly verified exchange of data signals between the operator and responder units 10,11, is complete the responder unit 11 actuates an actuating means 25 which in the present example comprises a circuit which provides power to a solenoid, to move a dead bolt of the lock of door 12.

If the dead bolt is in an extended condition such that the door 12 is locked in its jamb 16, the solenoid will be actuated to withdraw the bolt to unlock the door and permit the door 12 to be opened. Conversely, if the dead bolt is already withdrawn, the solenoid will be driven by the actuating means to extend the bolt into engagement with a keeper of the jamb 16 thus to lock the door 12 in its closed position.

Each of the operator unit 10 and responder unit 11 comprises a programmable microprocessor, which is preferably software configured so that the operator and responder units 10, 11 operate as described. Each unit 10, 11 thus learns from the other unit which data set A-F to expect to receive from the other of the units 11, 10 during data exchange and only transmits the correct next data signal to the other unit when the incoming data signal has been verified as being the correct expected data signal.

The microprocessor may comprise a ROM, and/or a RANI. and/or an EPROM, and/or an EEPROM and/or ASIC, as desired.

The responder unit 11 may be connected to auxiliarv devices, each auxiliary device having an associated actuating means which is actuated by responder unit 11 under the control of the operator unit 10 as hereinbefore described, to perform an operating function.

Various modifications may be made without departing from the scope of the invention.

Particularly, in the example described, the signals transmitted between the operator and responder units 10, 11 have been described as comprising infrared signals. Any other types of signal suitable to a particular application could alternatively be used, such as radio or ultrasonic signals.

In the example described, the responder unit 11 is mounted in a door 12, although for a similar application could alternatively be mounted in the jamb 16.

The responder unit 11 may be used for a wide variety of other applications, in each case the responder unit 11, when the exchange of data signals is completed, actuating the actuating means so that an operating function can be performed. For example, the actuating means 25 instead of driving a solenoid, may actuate a relay, a switch or a motor, and the operating function may comprise the switching on or off of a lamp, a motor, a solenoid or any other operating function desired.

If desired, the apparatus can be arranged to permit only a predetermined time limit for data exchange between the operator and responder units 10,11, to be completed, to provide additional security against any unauthorised attempt to actuate the actuating means.

Also, if desired, after an unsuccessful attempt by an unauthorised person to activate the actuating merans, the apparatus may require a predetermined time to elapse before further attempts may be made.

If desired, there may be provided means to override the signalling apparatus described. For example, the operator and/or responder units 10,11, may be programmed so that the door 12 cannot be opened, or can only be opened between certain times.

In an application of the invention to the control of a valve for example, the valve may be arranged to remain open or closed if a parameter is exceeded.

e.g. flow rate or temperature, even though the responder unit 11 receives correct data signals from a legitimate operator unit 10.

In another embodiment, not shown, and in a suitable application, instead of the responder unit 11 actuating the actuating means 25, the operator unit 10 may actuate an actuating means to enable an operating function to be performed. In this event, the responder unit 11 may be portable and the operator unit 10 a fixed or portable unit as desired.

In yet another embodiment, the operator unit which sends the initial signal may be actuated automatically, for example by a person wearing or carrying the unit, entering a monitored area. When data exchange between the operator and responder units is complete, the operator or the responder unit may be arranged to actuate the actuating means.

If desired, means may be provided to enable the operator and/or responder units to be reprogrammed to send and expect to receive different data sets. Such means may be provided by a mobile scanner which is able to interact with the operator and/or responder units 10,11, by infrared, radio, ultrasonic or other signals.

The features disclosed in the foregoing description the following claims or the accompanying drawings, expressed in their specific forms or in the terms or means for performing the desired function, or a method or process for attaining the disclosed result, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A signalling apparatus comprising an operator unit and a responder unit, each of the operator and responder units comprising means to transmit and receive data signals from one to the other, each of the operator and responder units being adapted to verify that any data signal received thereby is that which is expected from the other unit, one of the operator and the responder units, when data signal exchange between the operator and responder units is completed, actuating an actuating means to enable an operating function to be performed.

2. An apparatus according to claim 1 wherein the signals transmitted between the operator and responder units are infrared signals.

3. An apparatus according to claim 1 or claim 2 prior to the data signal exchange, the operator unit is adapted to transmit an initial signal to the responder unit.

4. An apparatus according to claim 3 wherein the initial signal transmitted by the operator unit contains information about the subsequent data signal or signals the operator unit is to transmit.

5. An apparatus according to claim 3 or claim 4 wherein upon sensing the initial signal from the operator unit, the responder unit transmits an initial response signal to the operator unit which contains information about the subsequent data signal or signals to be transmitted by the responder unit.

6. An apparatus according to claim 5 wherein upon receiving the initial signal from the operator unit, the responder unit switches from a quiescent mode to a responsive mode and transmits the initial response signal to the operator unit.

7. An apparatus according to claim 6 wherein after being inactive for a preset time after data exchange, the responder unit returns itself to a quiescent mode in which it is ready to recognise the initial signal from the operator unit.

8. An apparatus according to claim 6 wherein the responder unit returns to a quiescent mode after data exchange upon receipt of a particular signal from the operator unit.

9. An apparatus according to any one of claims 1 to 8 wherein the operator unit has in a memory thereof, a plurality of sets of data, the operator unit selecting one of the sets of data and transmitting the selected data set to the responder unit during the data exchange.

10. An apparatus according to claim 9 wherein the operator unit selects which of the plurality of sets of data to transmit, randomly.

11. An apparatus according to claim 9 or claim 10, where appendant to claim 4, wherein the initial signal transmitted by the operator unit informs the responder unit which of the sets of data to expect to receive from the operator unit during the data exchange.

12. An apparatus according to any one of claims 1 to 11 wherein the responder unit has in a memory thereof, a plurality of sets of data, the responder unit selecting one of the sets of data and transmitting the selected data set to the operator unit during the data exchange.

13. An apparatus according to claim 12 wherein the responder unit selects which of the plurality of sets of data to transmit, randomly.

14. An apparatus according to claim 12 or claim 13, where appendant to claim 5, wherein the initial response signal transmitted by the responder unit informs the operator unit which of the sets of data to expect to receive from the responder unit during the data exchange.

15. An apparatus according to any one of the preceding claims wherein the data transmitted during the data exchange comprises any numeric, alphabet or other character from an ASCII keyboard, or a combination of any of these.

16. An apparatus according to any one of the preceding claims wherein in the event that the responder unit or the operator unit receives a data signal at least during the data exchange, which is verified by the unit as not being that expected from the other unit, the respective responder or operator unit is adapted to transmit a false data signal.

17. An apparatus according to claim any one of claims 1 to 16 wherein the operator and responder units comprise microprocessors, the microprocessors or the circuits of which the microprocessors are a part, of the operator and/or responder units being software configured and comprising a RAM, and/or a ROM, and/or an EPROM and/or EEPROM and/or ASIC.

18. An apparatus according to any one of the preceding claims wherein at least one of the operator and responder units, is fully portable having its own battery power supply.

19. An apparatus according to any one of the preceding claims wherein one of the operator or responder units is powered from the mains, optionally with a battery back up.

20. An apparatus according to claim 19 wherein the operator unit and/or the responder unit has a battery backup power supply.

21. An apparatus according to any one of the preceding claims wherein the actuating means comprises a circuit or switch which is arranged to supply power or discontinue the supply of power to an operating means.

22. An apparatus according to claim 21 wherein the operating means comprises a solenoid or an electrical switch or a motor.

23. A signalling apparatus substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

24. Any novel feature or novel combination of features as herein defined and/or shown in the accompanying drawings.