WO2013011259A1

WO2013011259A1 - Alerting system

Info

Publication number: WO2013011259A1
Application number: PCT/GB2012/000599
Authority: WO
Inventors: Leonard Maxwell
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-18
Filing date: 2012-07-17
Publication date: 2013-01-24
Anticipated expiration: 2014-01-18
Also published as: GB2493042A; GB201112339D0; GB201203483D0

Abstract

A system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game is disclosed. The system comprising a referee module 10 to be worn by the referee during use and at least one player module 12 to be worn by a respective player during use. The referee module comprising a microphone, means for detecting a predetermined audio signal received through the microphone, and a transmitter responsive to detection of the predetermined audio signal to transmit an alert signal to a receiver of the or each player module. The player module further comprises means to alert the or each player to receipt of the alert signal.

Description

Alerting system

Field of the Invention

The present invention relates to an ale rTng system, apparatus and method. More especially the invention relates to an alerting system, apparatus and ^"method designed to assist hearing-impaired people in sporting events and which is useful for training purposes .

Background of the Invention

It is difficult for persons with hearing impairment to participate in sports games that require aural signals, such as a whistle or a shout to signify events within the game. If a player cannot hear a referee or umpire's whistle, then they will not know that an event has occurred. The present invention seeks to provide a system including apparatus for being worn in a game, for example by a person with a hearing impairment and also a referee, umpire, assistant, official or coach to allow the person with the impairment to instantly recognise when a signal has been made by the referee etc.

Summary of Invention

According to one aspect of the invention, there is provided a system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game, the system comprising a referee module to be worn by the referee during use and at least one player module to be worn by a respective player during use, the referee module comprising a microphone, means for detecting a predetermined audio signal received through the microphone, and a transmitter responsive to detection of the predetermined audio signal to transmit an alert signal to a receiver of the or each player module, the player module further comprising means to alert the or each player to receipt of the alert signal.

The detecting means is preferably configured to detect, and the transmitter is responsive to, an audio signal corresponding to a referee's whistle or the like. For this purpose, a digital or analogue processing means can be provided to identify the appropriate frequency/pitch of the whistle. In the case of a digital processing means, a signature matching the whistle sound, when digitised, can be stored, and a processor used to perform the comparison and any required filtering to remove background noise.

The microphone may be configured to have a pickup range of, substantially, four feet or less. Again, this is to avoid the transmitter sending an alert signal in response to background noise, or perhaps from other whistles used further away on adjoining pitches.

The alert means of the player module may comprise a vibrating unit responsive to receipt of the alert signal. Such a vibrating unit is a type of so-called haptic actuator for providing feedback to a body part of a wearer. As an alternative to a vibrating unit, other types of haptic actuators might be employed.

The referee module and the or each player module may comprise means for establishing a paired data channel over which the alert signal is transmitted from the referee module to the or each player module using a pairing key or code.

The pairing means of the or each player module may be configured to operate in a pairing/learn mode.

In said mode, detection of a predetermined audio signal at the. referee module may be effective to cause transmission of the pairing key or code to the or each player module. The pairing means of the referee module and the or each player module can be configured to operate in the pairing/learn mode in which the pairing key or code is generated at one module and transmitted to the or each other module. In the preferred embodiment, the referee module is configured to generate the pairing key or code when in the pairing/learn mode and to transmit said key or code to the or each player module operating in the pairing/learn mode.

The system may further comprise a control module configured to emit a control signal, and in which the referee module and/or the or each player module is configured to enter its pairing/learn mode in response to receiving said control signal. The control module may comprise a unit with a surface through which the control signal is wirelessly emitted and in which the referee module and/or the or each player module is configured to enter their respective pairing/learn modes when swiped along said control module surface.

The control module may be joined as part of a single physical unit with a charging module configured to charge an internal battery of the modules.

The charging module may be configured to charge the modules using inductive charging. The charging module may be configured to charge simultaneously a plurality of modules.

The referee module and the or each player module may be of substantially similar appearance and each may have an electronic visual indicator thereon responsive to being switched on or being charged to indicate whether the module is a referee module or a player module. Light Emitting Diodes (LEDs) or a Liquid Crystal Display (LCD) may be used for this purpose. One colour may indicate a referee module and a different colour indicates a player module. The LED or LCD may have a modified appearance when being charged and/or in the learning mode. The referee module and the or each player module may each be provided with an arm or leg -band for being mounted on, and located next to, a wearer's arm or leg.

According to a second aspect, there is provided a system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game, the system comprising: a referee module * having a microphone, means for detecting a predetermined audio signal and means responsive to said detection to transmit an alert signal over a paired communications channel; a plurality of player modules for being worn by players of a game, each player module having a receiver for receiving the alert signal over the paired communications channel from the referee module and, means responsive to receiving the alert signal to initiate a haptic actuator, for example a vibrating unit, for signalling the alert signal to the wearer.

The system may further comprise a charging and control module for charging the referee and player modules and which is further configured to put one or more modules into a learn mode in which a paired communications channel is established between the referee module and each of the player modules.

According to a third aspect, there is provided a referee module for use in the system according to the first or second aspects defined above.

According to a fourth aspect, there is provided a player module for use in the system according to the first or second aspects defined above.

According to a fifth aspect, there is provided a system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee, the system comprising: a first module for use by a referee's assistant, the first module

r

comprising a button or switch, and a transmitter responsive to user operation of the button or switch to transmit a first alert signal; and at least one player module to be worn by a respective player during use, the or each player module comprising a receiver and means responsive to receipt of the first alert signal to control a visual or haptic alert device for alerting the player.

The first module may comprise a plurality of buttons or switches, and the transmitter may be responsive to user operation of the buttons or switches to transmit a different respective alert signal, and wherein the at least one player module may be configured to control the visual or haptic alert device dependent on the received alert signal.

According to a sixth aspect, there is provided a method for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game, the method comprising :

in a referee module, detecting a predetermined audio signal received through a microphone, and responsive to detection of the predetermined audio signal, transmitting an alert signal, and

in a player module, responsive to detection of the alert signal, outputting a further signal to alert the or each player to receipt of the alert signal.

A computer program may be provided which, when executed by a processor, is operable to perform the above described method steps .

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying figures, in which

Figure 1 is a schematic illustration of components of a system according to a first embodiment; Figures 2(a)- (c) are schematic illustrations showing how modules of the Figure 1 system can be initiated and charged;

Figure 3 is a schematic illustration of how modules of the Figure 1 system are put into a learn mode;

Figure 4 is a block ^' diagram showing functional components of a first type of module of the system shown in Figure 1;

Figure 5 is a block diagram showing functional components of a second type of module of the system shown in Figure 1;

Figure 6 is a flow chart indicating processing steps performed by the first type of module, as shown in Figure 4; and

Figure 7 is a flow chart indicating processing steps performed by the second type of module, as shown in Figure 5.

Detailed Description of Preferred Embodiments

In a first embodiment, to be described with reference to the Figures, an alert system is employed in which the whistle sound made by a sports referee or umpire is detected by a microphone within a referee transmitting module and is effective to cause transmission of an alert signal to one or more player receiving modules being worn by players and to which the referee module is paired. In this way, players with a hearing impairment can be alerted to the blowing of the whistle notwithstanding the fact they cannot hear it.

Referring first to Figure 1, an alert system according to the first embodiment comprises a referee transmitting module 10, at least one player receiving module 12, an inductive charging block 14 and an AC power adapter 16 for powering the charging block.

Each module 10, 12 is fully enclosed, shock resistant and waterproof. Each module 10, 12 has substantially the same appearance in terms of its outer casing. Referee Module 10

The referee module 10 comprises a printed circuit board and associated circuit components. Referring to Figure 4, said circuit components include a controller/processor 106, . one or more rechargeable Ni-MH batteries 116, a microphone 118, a tri colour LED 120, RAM 114, a wireless communications module 122 and associated antenna 124, and a memory 112 on which is stored an operating system 126 and one or more software applications 128. A Hall Effect switching device (not shown) can also be provided. The controller/processor 106 is arranged to operate under the control of the software application (s) 128. The controller 106 is connected to each of the other components (except the battery 116) in order to control operation thereof.

The memory 112 may be a non-volatile memory such as read only memory (ROM) a hard disk drive (HDD) or a solid state drive (SSD) . The RAM 114 is used by the controller 106 for the temporary storage of data. The operating system 126 may contain code which, when executed by the controller 106 in conjunction with RAM 114, controls operation of each of the hardware components of the terminal .

The controller 106 may take any suitable form. For instance, it may. be a microcontroller, plural microcontrollers, a processor, or plural processors.

The microphone 118 is associated with an analogue to digital converter (ADC) (not shown) that converts the received audio signal into data for processing by the controller 106 under control of the software application 128. The software application 128 is configured to perform the following method steps, for which also refer to Figure 6:

1. receiving audio data from the microphone and ADC; 2. identifying whether the received audio data corresponds to predetermined reference data, e.g. corresponding to the data signature of a referee's whistle, and if so;

3. transmitting a wireless alert signal.

The predetermined reference data is stored on the memory 112 and can be provided as a factory default, or stored as part of a user- initiated learn process. Step 2 is a data processing step that involves comparing the received audio data with the signature represented by the reference data to identify a match, or substantial match. This may employ frequency/pitch matching and other known methods.

As will be described further below, the wireless alert signal transmitted in step 3 is done over a coded channel which is established in a prior learning mode; specifically, a pairing or binding code is generated at the referee module 10 and passed to the or each player module 12 to ensure that the alert signal is only understood or detected by paired player modules. This avoids interference which can occur if different sports events (e.g. different soccer matches) are taking place in close proximity.

The above digital processing steps can also be performed using analogue circuitry as an alternative.

Player Module (s) 12

The or each player module 12 comprises a printed circuit board and associated circuit components. Referring Figure 5 , said circuit components include a controller/processor 206, one or more rechargeable Ni-MH batteries 216, a haptic actuator in the form of a vibrating module 218, a tri-colour LED 220, RAM 214, a wireless communications module 222 and associated antenna 224, a memory 212 on which is stored an operating system 226 and one or more software applications 228. A Hall Effect switching device may also be provided. The controller/processor 206 is arranged to operate under the control of a computer program which, when executed by the processor, performs certain functions. The controller 206 is connected to each of the other components (except the battery 216) in order to control operation thereof.

The memory 212 may be a non-volatile memory such as read only memory (ROM) a. hard disk drive (HDD) or a solid state drive (SSD) . The RAM 214 is used by the controller 206 for the temporary storage of data. The operating system 226 may contain code which, when executed by the controller 206 in conjunction with RAM 214, controls operation of each of the hardware components of the terminal .

The controller 206 may take any suitable form. For instance, it may be a microcontroller, plural microcontrollers, a processor, or plural processors.

The controller 206, under control of the software application 228, is configured to receive via the antenna 224 and associated wireless communication module 222 an alert signal transmitted from the referee module 10 over the paired communications channel.

The software application 228 is configured to perform the following method steps, for which refer also to Figure 7 : receiving the alert signal; and

responsive to the alert signal, operating the hapt actuator, i.e. causing the vibrating module to vibrate.

The above steps can also be performed using analogue circuitry as an alternative.

Both the referee module 10 and player module 12 are designed to be worn by a person during a sports game. Typically they will be worn within an armband. The armband may comprise an elasticated band with a retaining pocket in which the relevant module 10, 12 sits. The modules 10, 12 are removable from the main armband structure to allow separate cleaning and washing of the modules and armbands .

During use, and when the referee blows a whistle, the microphone 118 within the referee module 10 receives the audio signal which is analogue to digital converted (ADC) and passed to the controller 106 of the module. The controller 106 is arranged, under control of the software application 128 to analyse the digital data, and detect the whistle sound by means of comparing it with the stored reference data.

The pick-up detection range of the microphone is limited to approximately 4 feet around the referee so that background sounds will not be detected.

Once detected the controller 106 of the referee module 10 transmits a secure coded RF signal to all associated player modules 12. As indicated above, this association is set in a prior pairing or binding operation in a learn mode. Once received, the player modules processors will cause the vibration module to vibrate thereby alerting the player to the fact that the referee has blown the whistle.

The modules 10, 12 are initially provided in a factory default or sleep mode to preserve battery life.

Charging Unit 14

The charging unit 14 is a module which combines in one integral unit the functionality of an inductive charger and a command module for initiating the system and for putting the referee and player modules 10, 12 into a learn mode and operational mode depending respectively on the orientation of the module, to be described below. The AC power adaptor 16 connects the charging unit 14 to mains power. To initiate the system, a user swipes the referee and player modules 10, 12 across one end of the charging unit 14, for which see Figure 2(a). Specifically, swiping is performed side-on along an end face of the charging unit 14 which comprises internal circuitry for emitting a wireless control signal which is receivable by the modules 10, 12.

In response to being swiped side-on in the above manner, each of the referee and player modules 10, 12 indicates their oken' state and whether they are a referee and player module by means of their in-built LED, 120, 220. The LEDs 120, 220 show different colours indicating whether the respective module is a referee module 10 (e.g. yellow) or a player module 12 (e.g. green).

To fully charge a module 10, 12, the module is placed fully over the charging unit 14, for which see Figure 2(b). The optimal position for charging is having the module 10, 12 adjacent the lower edge of the charging unit 14, with the LED 120, 220 on the left-hand side. A marking may be provided on the charging surface indicating the specific position where the module 10, 12 should be placed. Alternatively, or additionally, a projecting lip can be provided on the lower edge of the charger to indicate to a user this optimal charging position whereby the module 10, 12 rests on the lip.

As can be seen from Figure 2(c), this charging module 14 can charge up to three modules at any one time. It will be appreciated that the module could comprise more sections to increase the number of modules that can be charged simultaneously.

Setup Process and Learn Mode In order to avoid interference and/or prepare the referee, and player modules 10, 12 for a game, an initial setup process is used.

In this case, each player module 12 is synchronised or paired or bound with a referee module 10 by first placing the modules in a "learn mode". The modules are placed into learn mode by means of a user swiping the modules down the end of the charger unit 14, as is shown in Figure 3. Again, swiping is performed along an end face of the charging unit 14 which comprises internal circuitry for emitting the above-mentioned wireless control signal receivable by the modules 10, 12. Note that the orientation of the module 10, 12 in this case is different from that used in the initiation step referred to above, and shown in Figure 2(a). To initiate the learn mode, the base/bottom of the module 10, 12 is swiped along the end face.

Circuitry in the modules 10, 12 is configured to identify the orientation in order to understand whether the received control signal is to initiate the module or put it in the learn mode. For example, a first detector (not shown) is provided in the side of the module for detecting the initialisation side-on swipe and a second detector (not shown) is provided in the base of the module for detecting the learn mode setup.

The LED 220 of the player modules 12 is configured to change colour to signify that the module is in learn mode and/or when it is synchronised with the referee module 120 ready for use. Alternatively, or additionally, the LED 220 may strobe.

The referee module 10 is paired with the player module (s) 12 ether by blowing a whistle, which causes generation of a pairing key or code which is transmitted to the player module (s) to cause pairing. Alternatively, the referee module 10 is swiped down the side of the charger module 14 as indicated above to cause generation and transmission of the pairing key or code.

The pairing key or code generated at the referee module 10 may be unique to that module or is changed to one that is different from the previous, or a plurality of previously-generated keys or codes. The pairing key or code may be generated randomly or by incrementing a counter which acts as a seed.

The or each player module 12 will receive the transmitted pairing key or code from the referee module 10 for storing in the memory 212. It will remain stored until a new key or code is learnt or the memory is cleared.

To clear the current pairing key or code from the memory 212 of a player module 12, the module should be placed into learn mode as described above and the module then swiped for a second time; this will take the module out of the learn mode and clear the memory which is indicated by the LED 220 turning off.

Although a vibrating module 218 is provided in this case as the means to alert a wearer as to the alert signal, other forms of haptic actuator may be used to provide feedback to a wearer' s body .

Instead of providing the above-described functionality within dedicated referee and player modules 10, 12, the functionality can be provided within an application for storing and execution on a user terminal such as a smartphone, PDA or tablet. Most smartphones, for example, include a microphone and vibrating module as well as wireless transmission and reception capabilities. Accordingly, the smartphone can operate under the control of an application which can provide either or a selected one of the referee module functionality and player module functionality, e.g. as shown in Figures 6 and 7 respectively. Separate applications can be provided, or a combined application switchable between the two modes. 000599

14

The software application 128, 228 of both modules 10, 12 can be modified to generate, and respond to, different alert signals. For example, at the referee module 10, a first alert signal can be transmitted in response to receipt of an audio signal of first duration or signature, whereas a second, different, alert signal is transmitted in response to receipt of an audio signal or second, different duration or signature. At the player terminal 12, the type of feedback, whether vibration or otherwise, given to the wearer is different depending on the alert signal received. The vibrating module 218 may for example vibrate for a different duration, or vibrate in distinct pulses to help the wearer distinguish between the received audio signals.

Typical hardware specifications of the referee module 10 (transmitter), player module 12 (receiver) and charger module 14 are provided below.

Transmitter

Battery voltage 4.8V DC (4* 1.2V)

Battery capacity 120mA

Battery type 1/3 AAA Nickel metal hydride

Battery Charging Constant current via inductive coupling

charger

Charge Current 12mA (C/10) .

Operating current Transmit 70mA

active 2mA

Standby 50 hours . (no activations)

time (active)

Standby time (sleep 150 hours

mode)

Number off > 100 from a full charge over a 90 minute activations game

Transmit Frequency 869.5MHz

Transmit Power 70 W

Frequency control Crystal controlled PLL

Out of band Better than -65dbm

emissions

Bandwidth +/- 25Khz @-3dbm

Modulation Mode OOK

Code Format 8 Bit + 1 start Bit allowing 255 unique

codes expandable to 16.7 million if requ

Antenna Internal Tuned Loop

Approvals EN 300 - 220

Dimensions (mm) 68 x 47 x 20mm

Weight 60 grams

Operat ng 0° to +40° C

Temperature

Plastic ABS Polycarbonate mix Receiver

Battery voltage 4.8V DC (4* 1.2V)

Battery capacity 120mAh

Battery type 1/3 AAA Nickel metal hydride

Battery Charging Constant current via inductive coupling charger

Charge Current 12mA (C/10) .

Operating current Receive 13 mA

sleep mode SOOuA

Average active current 1mA

Standby time (active) 100 hours .

Standby time (sleep 30 days

mode)

Activations > 100 from a full charge over a 90 minute game

Receive Frequency 869.5MHz

Receive Sensitivity -109dBm

Image rejection Better than 53dbm suppression

Frequency control Crystal controlled PLL

RF emissions Less than - 76 dbm

Bandwidth +/- 75khz

Receiver type Single conversion with 10.7mhz IF

Modulation Mode OOK

Code Format 8 Bit + 1 start Bit allowing 255 unique codes expandable to 16.7 million if required

Antenna Internal Tuned Loop

Approval s EN 300 - 220

Dimensions (mm) 68 x 47 x 20mm

Weight 60 grams

Operating Temperature 0° to +40° C

Plastic ABS Polycarbonate mix

Charger

Supply vol tage 20V DC

Supply Current 250mA Maximum

Charge type Constant current Via inductive coupling

Charge time 16 hours maximum from flat

Charge Current 12mA (C/10) (set by the pager on charge)

Dimensions (mm) 150 x 87 x 35mm (width*depth*high)

Weight 220 grams

Operating Temperature 0° to +40° C

Plastic ABS Pol carbonate mix

A second embodiment will now be described.

In this embodiment, instead of a referee carrying a referee module, a linesman, coach or refereeing assistant carries a third, different, module which comprises a key, button or switch, and preferably two or more keys, buttons or switches. Operation of the or each key, button or switch on this third module causes transmission of a respective alert signal to one or more player modules with which the third module is paired (using the same learning mode operation described above) . At the player module (s), a different alert is provided to the wearer depending on the button pressed, and therefore the alert signal received. The alert may be a particular duration of vibration, or sequence of vibrations.

For example, a linesman on hearing a referee blow a whistle for a free-kick may press a first button which causes transmission of a first alert signal to each player module. This in turn causes a vibration on the player modules of a first duration, e.g. 1 second. If the linesman hears the referee blow the whistle for the end of half or game (which will generally sound different) then a second button is pressed to cause a second alert signal to be transmitted. At the player modules, a vibration of longer duration may be initiated, or a pulsed vibration.

In this second embodiment, no microphone is required at the third module .

It will be appreciated that the foregoing are merely an examples of embodiments of an alert system and just some examples of its use. The skilled reader will readily understand that modifications can be made thereto without departing from the true scope of the invention.

Claims

1. A system for alerting a person with a hearing impairment participating in a game to a signal■ provided by a referee of the game, the system comprising a referee module to be worn by the referee during use and at least one player module to be worn by a respective player during use, the referee module comprising a microphone, means for detecting a predetermined audio signal received through the microphone, and a transmitter responsive to detection of the predetermined audio signal to transmit an alert signal to a receiver of the or each player module, the player module further comprising means to alert the or each player to receipt of the alert signal.

2 . A system according to claim 1, wherein the detecting means is configured to detect and the transmitter is responsive to, an audio signal corresponding to a referee's whistle or the like.

3. A system according., to claim 1 or claim 2, wherein the microphone is configured to have a pickup range of, substantially, four feet or less.

4. A system according to any preceding claim, wherein the alert means of the player module comprises a vibrating unit responsive to receipt of the alert signal.

5. A system according to any preceding claim, wherein the referee module and the or each player module comprise means for establishing a paired data channel over which the alert signal is transmitted from the referee module to the or each player module using a pairing key or code.

6. A system according to claim 5, wherein the pairing means of the or each player, module is/are configured to operate in a pairing/learn mode and in which, in said mode, detection of a predetermined audio signal at the referee module is effective to cause transmission of the pairing key or code to the or each player module.

7. Ά system according to claim 5 or claim 6, wherein the pairing means of the referee module and the or each player module is/are configured to operate in a pairing/learn mode in which the pairing key or code is generated at one module and transmitted to the or each other module.

8. A system according to claim 7, wherein the referee module is configured to generate the pairing key or code when in the pairing/learn mode and to transmit said key or code to the or each player module operating in the pairing/learn mode.

9. A system according to claim 7 or claim 8, further comprising a control module configured to emit a control signal, and in which the referee module and/or the or each player module is configured to enter its pairing/learn mode in response to receiving said control signal.

10. A system according to claim 9, wherein the control module comprises a surface through which the control signal is wirelessly emitted and in which the referee module and/or the or each player module is configured to enter its pairing/learn mode when swiped along said control module surface.

11. A system according to claim 9 or claim 10, wherein the control module is joined as part of a single physical unit with a charging module configured to charge an internal battery of the modules .

12. A system according to claim 11, wherein the charging module is configured to charge the modules using inductive charging.

13. A system according to claim 11 or claim 12, wherein the charging module is configured to charge simultaneously a plurality of modules .

14. A system according to any preceding claim, wherein the referee module and the or each player module are of substantially similar appearance and each has an electronic visual indicator thereon responsive to being switched on or being charged to indicate whether the module is a referee module or a player module .

15. A system according to any of claims 5 to 12, or any claim dependent thereon, wherein the referee module and the or each player module has an electronic visual indicator thereon which changes appearance when the respective module is in the pairing/learn mode.

16. A system according to any preceding claim, wherein the referee module and the or each player module are each provided with an arm or leg -band for being mounted on, and located next to, a wearer's arm or leg.

17. A system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game, the system comprising:

a referee module having a microphone, means for detecting a predetermined audio signal and means responsive to said detection to transmit an alert signal over a paired communications channel; a plurality of player modules for being worn by players of a game, each second module having a receiver for receiving the alert signal over the paired communications channel from the referee module and, means responsive to receiving the alert signal to initiate a haptic actuator, for example a vibrating unit, for signalling the alert signal to the wearer.

18. A system according to claim 17, further comprising a charging and control module for charging the referee and player modules and which is further configured to put one or more modules into a learn mode in which a paired communications channel is established between the referee module and each of the player modules.

19. A referee module for use in the system according to any preceding claim.

20. A player module for use in the system according to any preceding claim.

21. A system for alerting a person with a hearing impairment participating in a game to a signal provided by a referee, the system comprising:

a first module for use by a referee's assistant, the first module comprising a button or switch, and a transmitter responsive to user operation of the button or switch to transmit a first alert signal; and

at least one player module to be worn by a respective player during use, the or each player module comprising a receiver and means responsive to receipt of the first alert signal to control a visual or haptic alert device for alerting the player.

22. A system according to claim 21, wherein the first module comprises a plurality of buttons or switches, and the transmitter is responsive to user operation of the buttons or switches to transmit a different respective alert signal, and wherein the at least one player module is configured to control the visual or haptic alert device dependent on the received alert signal.

23. A method for alerting a person with a hearing impairment participating in a game to a signal provided by a referee of the game, the method comprising: