WO2001033528A1

WO2001033528A1 - Monitoring apparatus

Info

Publication number: WO2001033528A1
Application number: PCT/GB2000/004233
Authority: WO
Inventors: David Gooch
Original assignee: Kindertec Ltd.
Priority date: 1999-11-03
Filing date: 2000-11-03
Publication date: 2001-05-10
Also published as: AU1160101A; GB9925899D0

Abstract

A reassurance monitoring apparatus is disclosed comprising a first assembly to be located in a room with the person being monitored including a microphone adapted to convert sounds generated by the patient into an audio signal, a transmitter adapted to transmit a first signal representative of the audio signal, a receiver adapted to receive a second signal and a speaker adapted to generate an acoustic signal from information in the second signal; a second assembly located by the carer and comprising a microphone adapted to convert sounds generated by the carer into an audio signal, a transmitter adapted to transmit a third signal representative of the audio signal, a receiver adapted to receive the first signal and a speaker adapted to generate an acoustic signal from information in the first signal. The first assembly further includes at least one sensor adapted to generate an output signal indicative of a sensed parameter, the signal being transmitted by the transmitter to the receiver of the second assembly and the second assembly includes presentation means arranged to present information indicative of the sensed parameter to the carer.

Description

MONITORING APPARATUS

This invention relates to improvements in monitoring apparatus , and in particular to a reassurance monitoring apparatus for use by a carer in remotely monitoring the well-being of an adult or child that needs reassurance.

There are at present around 35 million carers in the UK and the USA alone who are responsible for looking after the well being of elderly or otherwise unfirm people who need care at home. A carer's primary need is monitor their "patients" well-being. Depending upon the condition of the patient this may require constant supervision.

Prior to recent advances in technology the only way to provide adequate care for a patient has been to ensure that someone is constantly on hand to regularly check the patient. Obviously, this is not always convenient or possible and at the least provides a severe restriction on the freedom of the carer.

At present, it is known to provide the patient with a panic-alarm button that is physically wired to a telephone. If the patient feels unwell the panic button can be activated which automatically dials a predetermined telephone number to alert staff, usually sited at a remote "call centre" . The service is expensive, typically requires periodic subscriptions to cover the costs of the call centre and relies upon the patient to recognise that they are unwell or in difficulty. It does not provide any information on the well being of the patient nor a direct link to the carer.

Initial market research has shown that many carers and patients experience a great deal of anxiety at night or when the carer is away from their charge. This anxiety is only partially relived by current products as the responsibility to monitor the well being of the patient either remains with the patient -as with panic alarm systems-or relies upon the carer making regular checks on the patient. An object of the present invention is provide apparatus which can be used by a carer to remotely monitor a patient and ameliorate the need to maintain regular physical contact with the patient in the home.

In accordance with a first aspect the invention provides a reassurance monitor for use by a carer to monitor a child or adult who requires reassurance, the apparatus comprising:

a first assembly to be located in a room with the person being monitored including a microphone adapted to convert sounds generated by the patient into an audio signal, a transmitter adapted to transmit a first signal representative of the audio signal, a receiver adapted to receive a second signal and a speaker adapted to generate an acoustic signal from information in the second signal; a second assembly located by the carer and comprising a microphone adapted to convert sounds generated by the carer into an audio signal, a transmitter adapted to transmit a third signal representative of the audio signal, a receiver adapted to receive the first signal and a speaker adapted to generate an acoustic signal from information in the first signal; and characterised in that the first assembly further includes at least one sensor adapted to generate an output signal indicative of a sensed parameter, the signal being transmitted by the transmitter to the receiver of the second assembly and in which the second assembly includes presentation means arranged to present information indicative of the sensed parameter to the carer.

It will of course be appreciated that the second signal (received by the first unit) and the third signal (transmitted by the second assembly) are essentially the same.

The invention thus provides a monitoring apparatus which allows two-way- audio communication between the carer and the person being monitored and additionally provides the carer with information on the well being of the person being monitored. This allows the carer to analyse the information remotely and provide reassurance to the monitored person as well as to allow them to ask questions to help improve their understanding of the situation.

Of course, it may be possible to provide a reassurance monitor that does not include any sensors or a presentation means but simply provides for conversation between the carer and the monitored person to provide reassurance.

The invention addresses the major shortcomings of prior art monitoring systems by giving the carer the ability to remotely observe the patient and talk to them. The patient is also reassured that the carer is on hand to provide immediate assistance or reassurance.

The transmitter and receiver of the first assembly may be adapted to drive an antenna to respectively transmit a radio signal to and receive a radio frequency signal from an antenna of the second assembly . The antennas may each comprise two antennas (or more) to provide diversity of reception.

Similarly, the transmitter and receiver of the second assembly may be adapted to drive an antenna to respectively transmit a radio signal to and receive a radio frequency signal from an antenna of the first assembly.

The radio frequency signal may encode the speech of the patient or carer and optionally the sensed information as digitally encoded information. This enables a high degree of immunity to interference to be achieved when compared with the transmission which has been encoded as an analogue signal. Digital information can also be encoded for security to prevent eavesdropping. Of course, for some applications analogue encoding may be employed.

The first assembly and/or the second assembly may further be adapted to facilitate telephone calls over a telephone network. This may be through appropriate physical connection to a telephone line or through the provision of a suitable transmitter/receiver that is compatible with a mobile telephone network. The first assembly may be adapted to transmit tone-dialling signals for transmission over the telephone network.

The first and/or second assembly may be adapted to transmit both audio data and receive audio data encoding conversation between the_. patient or carer and the person called over the telephone network. It may also be adapted to transmit the sensor data from the or each sensor associated with the first assembly across a telephone network.

It is especially advantageous for the second assembly to operate as a telephone as it allows the carer to communicate with a third party (such as the ambulance or police service or a doctor) from a remote location as well as communicating with the patient.

The second assembly may permit the carer to make telephone calls via the first assembly in the manner of a conventional radio telephone system. Thus, audio data may be exchanged between the first unit and the second unit and passed on to the telephone network by the base unit. It may be arranged to operate in accordance with the guidelines for the DECT telephone system.

The first assembly may include a base station that comprises a housing adapted to support the microphone and speaker and the transmitter/receiver. Alternatively, it may comprise a two part housing with a first part defining a base station housing the transmitter/receiver and the second part comprising a handset housing the speaker and the microphone. In the latter case the speaker and microphone may be connected to the transmitter/receiver by a hard-wired connection or a wireless connection.

In another arrangement, two sets of microphone and speaker may be provided with one set in each part of a two-part housing. The first housing may include a support cradle for the second housing and may be adapted to detect when the second housing is placed in the support cradle. The first assembly may include one or more sensors adapted to monitor one or more conditions of the patient and or/one or more sensors adapted to monitor surrounding environment.

The sensors may include a temperature sensor adapted to measure the ambient temperature of the environment surrounding the sensor. This sensor may be built into the base station (where provided) or may be a separately mounted sensor connected to the base station by a hard-wired link or a wireless connection.

The sensors may further include a pressure sensor adapted to be operated by the patient. It may comprise a pad which may be placed under the patient, or under a mattress, cushion or rug which the patient normally lies, sits or stands on. The pressure sensor may be adapted to detect the force exerted by the patient on the pressure sensor. It may conveniently produce a first signal indicating the presence of the patient on the sensor and a second signal indicating that the patient is not present.

The sensors may further include a panic alarm switch or button which can be operated by the patient if they are in difficulty or require assistance. This may be connected to the first unit by a hard-wired connection or a wireless link.

In addition, the sensors may include a location indicator for use with mobile patients which senses the location of the patient within a room or building.

It is most preferred that one or more of the sensors include a transmitter and that the first assembly includes a dedicated receiver which is responsive to the signals issued by the transmitter(s) . The dedicated receiver may be housed within the base station (where provided) or may be provided in a separate housing and hard wired to the first unit.

The panic alarm may comprise a housing shaped as a pendant which is worn by the patient on a necklace or chain that conceals or functions as an antenna for transmitting the sensed parameter (i.e. operation of the panic alarm) . Alternatively, it may be worn on the wrist like a wristwatch.

Each sensor may transmit a coded signal, the code being unique to each sensor and the receiver may be adapted to only receive these coded signals. The dedicated receiver may include an area of memory into which the codes may be stored. The memory may be programmable and a programming means for entering the codes to the memory may be provided.

The transmitter of the first assembly may be adapted to transmit a radio wave signal of substantially 433MHz that is detected by the detector of the second assembly.

Similarly, the transmitter of the second unit may be adapted to transmit a radio wave signal of substantially 433MHz that is detected by the detector of the first assembly.

The first assembly may be operated from one or more batteries or may be mains operated. It may comprise a plastic housing which contains the electronic circuitry required to process data from the input devices and to drive the output devices and the transmitter/receiver.

The first assembly may be adapted to provide hands free speech for the patient, allowing it to be located on a bedside cabinet or at some other convenient location in the room. By hands free speech we mean that the unit will automatically recognise sounds produced by the patient and transmit them to the second unit without the patient having to physically interact with the unit. For example, most simple telephones require the user to pick up a handset which activates the telephone. With hands free operation the unit is always ready to transmit and receive sound.

The second assembly may comprise a hand held unit. This may have an appearance similar to a cordless telephone handset with a main body housing the speaker and the microphone. It may be battery operated and include a battery compartment built into the housing which receives one or more batteries. The or each battery may preferably comprise a rechargeable battery.

The presentation means of the second assembly may include one or more visual displays or audible indicators. Examples are incandescent lights, light emitting diodes, loudspeakers and piezoelectric buzzers. This allows the carer to monitor the parameters sensed by the sensors remotely using the second assembly.

Where applicable, the visual display may include a liquid crystal display panel or other display of the temperature as sensed by the temperature sensor associated with the first unit.

A visual display of the pressure sensed by the pressure sensor (where provided) may also be given. This may comprise a light or an array of lights which vary in intensity with the output of the pressure sensor. For instance, the light or lights may normally be extinguished but may be illuminated when the pressure sensor detects that the patient has moved. An audible alarm may also or alternatively be raised.

The second assembly may also include one or more user-operable input devices . These may include a volume control switch that adjusts the volume of the output of the loudspeaker. A similar volume control may be provided at the first assembly.

An On/off switch may also be provided, as well as a mute switch that enables the carer to temporarily disable the microphone when a private conversation is required with a third party.

A further input device comprises a switch which when operated prevents the patient from using the first assembly as a telephone. This allows the user to prevent the patient from making nuisance phone calls. When the patient is barred any calls may instead be directed to the second assembly so that instead of making a telephone call the patient is put in voice contact with the carer. The bar can be cancelled by operating this input device if the carer is away to allow emergency calls to be made. Where appropriate the "bar" switch could be electronic and operated remotely from the second assembly.

A keypad may be provided on the second assembly whereby the carer can dial telephone numbers to make telephone calls. Operation of the keypad may be arranged to generate data that is transmitted to the base station. The base station may detect this information and dial the telephone number by generating a set of appropriate tone dial signals.

A still further input device may be adapted to permit the carer to disable one or more of the input devices connected to or forming part of the first unit. This allows the carer to prevent the second unit issuing unwanted visual or audible information form sensors which are not required. For example, the carer can disable the panic alarm sensor once it has initially been activated and acknowledged by the carer, or disable the pressure sensor input device if they know that the patient is out of bed or otherwise away from the sensor.

The apparatus may further include a charging unit which is adapted to receive the second assembly. This charging unit may include at least one conductive terminal that co-operates with one or more corresponding terminals on the second unit to permit electrical charge to flow from the charging unit to the second unit. This is suitable for charging any rechargeable batteries located in the second assembl) .

A light may be provided on the second assembly (or other visual or audible display) that informs the carer that the unit is being charged. A separate display may be provided that indicates the amount of charge stored in the battery or batteries.

In an alternative, or additionally the second assembly may comprise a handheld unit and the first assembly may include a docking bay for supporting the second unit whilst it is charged. The first assembly may also include one or more conductive terminals in the docking bay that co- operate with corresponding conductive terminals on the second assembly to permit electrical charge to flow from the first assembly to the second assembly. This allows the second assembly to be recharged by the first assembly.

The first assembly and/or the second assembly and/or the charging unit may include a memory interface adapted to receive a removable electronic memory device that contains data relating to the patient. This data could include details of the medication used or previously taken by the patient. The memory device may comprise a smart card which is received in a compatible slot in the assembly(s) .

In accordance with a second aspect the invention provides a monitoring apparatus comprising: a first telephone unit capable of transmitting and receiving audio signals over a telephone network, a second telephone unit capable of transmitting and receiving audio signals over the telephone network, and in which the first unit is adapted to transmit data sensed by one or more sensors whilst the second unit includes a presentation means adapted to display the sensed data.

It will be appreciated that the second aspect of the invention may encompass any of the features of the first aspect of the invention.

There will now be described, by way of example only, several embodiments of the present invention with reference to the accompanying drawings of which:

Figure 1 is a schematic overview of a monitoring apparatus in accordance with one aspect of the present invention;

Figure 2(a) is a plan view and 2(b) is a side view of the base unit and the handheld second unit of the apparatus;

Figure 3 is a view of the underside of the second unit (which is obscured in Figure 2(a) ; Figure 4 is a perspective view of a sensor pad for incorporation into the monitoring apparatus to monitor pressure applied to the pad by the patient;

Figure 5 is an illustration of a charging pedestal that can be used to recharge batteries in the second unit when placed on the pedestal;

Figure 6 is an illustration of a panic alarm comprising a pendant attached to a necklace;

Figure 7 is a schematic of the electronic circuitry of the base unit;

Figure 8 is a corresponding schematic of the circuitry of the second unit;

Figure 9 is representation of the mode of operation of the apparatus of Figure 1 ;

Figure 10 is a representation of the mode of operation of a modified apparatus including telephone network functionality;

Figure 11 is a representation of the mode of operation of an alternative apparatus which includes a telephone accessory; and

Figure 12(a) is a side view and (b) is a plan view of the telephone accessory shown in Figure 11.

The apparatus is illustrated schematically in Figure 1 of the accompanying drawings. It comprises several units that together permit a carer to monitor and communicate with a patient from a remote location. The key units, which will each be described in turn, are as follows:

First Unit (The "base" unit) Second unit (The "handset") Charger pedestal Bed Sensor Portable alarm OEM charger Pluggable receiver

The first unit (or "base unit") 1 is located by the patient, for example on a bedside cabinet. The second unit (or "handset") 2 is carried by the carer and allows information sent from the receiver to be monitored. It also allows two way radio frequency communication between the carer and the patient to be maintained. The second unit 2 is battery powered for maximum portability and can be placed on the charger pedestal 3 to recharge or top-up the batteries.

The first unit 1 is connected to a bed sensor mat 4 and portable alarm 5 to monitor the patient and allow the patient to alert the carer in an emergency, whilst the pluggable receiver 6 enables the first unit 1 to receive signals from the sensor mat and alarm using wireless communications protocols.

An important aspect of the assembly is the ability of the base unit 1 to connect to the telephone network. This allows either the patient to contact third parties from the base unit or the carer to make calls from the second unit via the base unit in the manner of a conventional cordless telephone.

Not all embodiments of the invention include the facility to operate as a telephone in this way.

THE BASE UNIT

The base unit 1 comprises a hollow plastic housing 100 as shown in the concept illustrations of Figure 2(a) and 2(b) of the accompanying drawings . A lower part of the housing 100 defines a base which is provided with four rubber feet 101 for stability on a flat surface (only two are visible) .

An electrical cable (not shown) provided with a suitable plug connects with a corresponding socket 102 provided in a rear face of the housing in turn connected to the electronic circuit within the housing. The cable, which is supplied with the base unit, includes a small transformer which is designed to be connected to a domestic electricity supply through an electrical plug and socket. The plug format and the rating of the transformer will vary depending upon the country of use for the apparatus. In all cases, only a low voltage is passed to the base unit along the cable, such a 5 volts DC.

The housing 100 accommodates an electrical circuit (not shown) which is powered from the electricity supply or from one or more rechargeable batteries located within a battery compartment that is covered by a lid on the base of the housing. The batteries can be recharged by drawing current from the mains power supply.

The electrical circuit interconnects various input devices including a microphone MP1 with various output devices including a radio frequency antenna ANT1 and a loudspeaker LSI .

The antenna ANT1 is wholly accommodated within the housing 100 and extends substantially vertically from the base of the housing to its upper surface when the housing 100 is placed in its position of use on a bedside cabinet or other suitable surface.

An upper face 103 of the housing includes a set of three small perforations 104a behind which the microphone MP1 is located. The microphone MP1 is adapted to produce an output signal in response to a range of frequencies corresponding to those present in human speech.

The upper face of the housing also includes a number of perforations 104b behind which is mounted the loudspeaker LSI that generates an audible waveform which permits speech to be reproduced . The loudspeaker LSI is connected to the electronic circuit by electrical cables and is driven from an audio signal generated by the electronic circuit located within the housing. An optional beeper, such as a piezo-electric speaker, may also be provided which is again connected to the electrical circuit by a suitable electrical cable. The beeper is used to issue an audible indication of operational status of the base unit. A thermistor TS is also located within the housing behind a set of openings 105 which permits air too circulate around the thermistor TS. The thermistor TS produces a temperature signal in the form of a voltage that increases as the ambient temperature increases. This signal is fed to the electronic circuit along an electrical cable.

On the side of the housing a small recess is provided into which a telephone socket 106 is accommodated. The socket receives a suitable plug of a telephone cable and is connected internally to the electronic circuit.

A night light 107 is provided at the front of the housing which provides a reassuring soft glow of light for the patient as well as helping the patient to identify the location of the unit in an unlit room such as at night time. A switch 108 next to the night light allows the patient to switch the night light on or off as required.

Other input devices located on the housing include a power On/Off switch 109 which can be operated by the user, a volume control switch/mute switch 110 which adjusts the volume of the sound generated by the loudspeaker and on some models a numeric key pad (not shown) which can be operated by the patient to initiate a telephone call using the base unit. The call pad is back-lit.

Finally, on the base of the housing 100 a row of contacts (not shown) are provided which permit the unit to programmed during production on the assembly line. These contacts are connected through a ribbon cable to the electronic circuit.

Finally the housing includes an area on its upper face which is adapted to receive the second unit 200 when it is not in use.

The electronic components associated with and forming a part of the base unit are shown schematically in Figure 7 of the accompanying drawings. The electronic circuit within the housing is provided on a single printed circuit board which carries a number of conductive tracks that extend from the input and output devices, power supply cable etc. to electrical components supported by the board. The circuit is protected from external sources of electromagnetic interference by a conductive shield which surrounds the circuit within the housing and connected to an earth point on the circuit board. The shield can be provided by coating the inside of the plastic housing with a conductive paint. Of course, care needs to be taken that the antenna is free to radiate without being blocked by the shield.

The circuit board supports a programmable processing unit or processor 700 which is driven from a quartz crystal oscillator 701 , a connection to the positive voltage supply 702 (from the batteries or the power cable) and a negative or earth connection 703. The processing unit 700 includes an area of memory 704 which contains a programme of operating instructions that are loaded during production through the terminals on the base of the housing 100.

The inputs to the processing unit are provided by connections from the tracks on the circuit board connected to the input devices (the power switch, the thermister 705 and the output of the pluggable receiver 706) .

The output of the microphone MP1 is fed to an amplifier 707 and then to a baseband processor 708. The baseband processor produces a digital signal indicative of the sound recorded by the microphone which is passed to an RF transceiver 709 which drives the antenna ANT1.

The processor 700 also produces a data output signal 713 dependent upon the status of the temperature sensor 705 and the output from the pluggable receiver 706. This data output encodes the sensor information and is fed to the baseband processor and then to the RF transceiver 709.

The antenna therefore radiates a radio frequency signal containing both audio information from the microphone and data from the sensors. THE SECOND UNIT

This comprises a small hand held device 200 similar in appearance to a mobile or cellular telephone. The device is illustrated in Figures 2(a) , 2(b) and Figure 3 of the accompanying drawings .

The unit 200 comprises a plastics housing 201 having an opening (not shown) on its underside that allows access to a battery compartment. A rechargeable battery can be located within the battery compartment which is connected to an electronic circuit within the housing. The battery provides all the power required by the electronic circuit and also powers the input and output devices.

The handheld unit 200 can be recharged by placing the hand-held unit 200 on a recharging pedestal where current is passed to the batteries through an array of electrical contacts on the base of the unit. The case design is symmetrical around the electrical contacts.

The unit includes a radio frequency antenna ANT2 for receiving radio frequency signals from and transmitting radio frequency signals to the antenna ANT1 of the base unit 100. The inside of the housing is also shielded to protect the electronic circuit from unwanted external sources of electromagnetic radiation.

The housing 200 supports a speaker LS2 towards one end behind a group of cut-outs 201 in the housing and a small microphone MP2 at the other end. The microphone is located behind three small cut-outs. Both the speaker LS2 and the microphone MP2 are connected to respective electronic amplifiers through suitable electrical cables.

The position of the speaker LS2 and the microphone MP2 and the shape of the housing 200 is chosen to permit the carer to speak into the microphone whilst listening to the sound generated by the loudspeaker. A secondary speaker (not shown) may be located on the rear of the unit which is more powerful than the first to permit hands free operation of the unit. The speaker is arranged to generate sufficient audio levels to allow voice output from the speaker to be clearly heard over a distance of up to 6 metres at normal speech levels.

In the centre of the housing 200 is a linear array of lights 202 such as a light emitting diodes located behind a plastic diffuser.

The housing also supports a visual display panel 203 for the presentation of visual information sent by the base unit including a display of the ambient temperature of the air around the base unit and of the status of any additional sensors such as the panic alarm or the sensor mat.

The housing 200 also supports a selection of input devices comprising user operable switches which are connected to the electronic circuit located within the housing through one or more cables. The switches perform the following functions:

The electronic circuit within the housing is provided on a printed circuit board and includes a selection of input and output devices located within the housing. The various parts of the electronic circuit and their interconnection with the other parts of the circuit are illustrated schematically in Figure 8 of the accompanying drawings .

The circuit is similar to that provided in the base unit. The circuit board supports a programmable processing unit or processor 800 which is driven from a quartz crystal oscillator 801 , a connection to the positive voltage supply 802 (from the batteries or the power cable) and a negative or earth connection 803. The processing unit 800 includes an area of memory 804 which contains a programme of operating instructions that are loaded during production through the terminals on the base of the housing 200. The inputs to the processing unit 800 are provided by connections from the tracks on the circuit board connected to the input devices (the power switch, the thermister 805 and the output of the pluggable receiver 806) .

The output of the microphone MP1 is fed to an amplifier 807 and then to a base band processor 808. The baseband processor 808 produces a digital signal indicative of the sound recorder by the microphone which is passed to an RF transceiever driven by a crystal oscillator 810 which drives the antenna ANT1.

The processor 800 also produces a data output signal 813 dependent upon the status of the keypad 805 and other switches provided on the housing. This data output is fed to the base band processor. This produces a digital signal indicative of the data which is fed to the RF transciever 809.

The antenna ANT2 therefore radiates a radio frequency signal containing both audio information from the microphone and data relating the position of the switches and the keys of the keypad 805.

The RF amplifier 809 and baseband processor 8908 also amplifies signals received by the antenna. These signals are passed to an audio amplifier 811 for reproduction of the extracted signal.

The output of the baseband receiver is also fed to the processing unit. This extracts the transmitted sensor data. The processing unit 800 processes this data before producing a signal indicative of the value of the data to a display 820 and/or and alarm buzzer 821.

On/off power 204-allows the user to switch off the unit to preserve battery power.

Volume control 205- adjusts the volume of the loudspeaker

Call function cancel-206- this can be used to prevent telephone calls being made from the base unit by the patient, for example by transmitting a signal to the base unit to disable the keypad of the base unit. Portable alarm function cancel- 208 disables any alarm signals generated when the panic alarm has been activated.

Hands free select- switches between hands free and normal operation by varying the sensitivity of the microphone and the amplitude of speech signals emitted by the loudspeaker.

Mute button - this may be combined with the volume control or as a separate switch 207.

The handset 200 is so constructed and arranged to provide 6 meters hands free full duplex operation for speech between the carer and the base unit when in the hands free setting. The radio signal sent by the transmitter should be sufficiently powerful to permit a 100 metre range between the base station and the hand held unit to be achieved when used indoors with an open field range of up to 400 metres.

The transmitted signal is encoded with a unique code so that the system will not interfere with similar systems used by neighbours, and provides for a 12 hour battery life between recharges.

CHARGING PEDESTAL

This is illustrated in Figure 5 of the accompanying drawings . The pedestal comprises a housing 300 which has a lower portion defining a base and a recess 301 on its upper face. A set of electrical contacts 302 are located at the base of the recess. The electrical contacts 302 cooperate with corresponding contacts provided on the handset 200 to permit charge to be supplied to the batteries in the handset 200. The recess 301 is arranged to accommodate the handset in a number of different orientations whilst still permitting charging.

The housing 300 contains a step-down transformer and a battery charge circuit supplied by the transformer. An electrical lead extends from the housing to permit connection of the transformer to a domestic electricity supply.

A small light emitting diode 303 is provided on the housing which is illuminated to indicate that the handset is correctly engaged with the pedestal for charging, whilst a further light emitting diode 304 is provided which is illuminated whenever power is connected to the pedestal.

THE SENSOR PAD

The sensor pad 400 is illustrated in Figure 4 of the accompanying drawings.

This is available as an optional accessory which provides an additional input to the base unit. The pad is supplied with a length of electrical lead that plugs into a discrete socket provided on the rear of the base unit 100. Alternatively, the sensor pad 400 may be connected to the base unit 100 through a wireless link, such as an infra-red connection. If the infra-red connection is provided, data may be transmitted periodically by the pad to the base unit.

The infra-red connection is achieved using a pluggable receiver 500 that is fitted to an input socket on the base unit 100. The sensor mat 400 includes a radio frequency transmitter that communicates with a radio frequency receiver in the pluggable receiver, for instance transmitting a coded signal at 433Mhz. The coding ensures that the pluggable receiver 500 only detects signals sent by the correct sensor pad 400 and not a pad on a neighbour's bed.

The pad 400 includes a battery compartment (not shown) and a pressure sensor which produces an output signal depending upon the pressure applied to the pad 400 by the patient. It may be placed under the patient or a mattress on which the patient lies . Depending on the sensitivity of the sensor pad it may either detect the presence of the patient or may detect the movement of the patient as they are breathing. The sensor 400 transmits a signal indicative of pressure at pre-set intervals. This preserves power when compared to a continuous transmission. However, if the sensed pressure changes it will transmit immediately, for example to indicate that the patient is no longer in bed or has stopped breathing. It will also transmit immediately that a patient gets into bed.

PLUGGABLE RECEIVER

The pluggable receiver 500 comprises a small plastics housing for a radio frequency receiver that detects signals around 433Mhz from the sensor pad or other input devices and passes the received signal to the base unit 100. Although it can not be seen in the accompanying concept drawings, the receiver is adapted plug into a recess provided in the base of the base unit and is unobtrusive in use.

The receiver includes a coding circuit which includes an area of memory into which a code indicating the encoding used by the input device is stored. Only received signals that include the code are passed to the base unit by the receiver.

To allow the code to be entered to the memory an infra-red input port or an array of conductive contacts are provided which co-operate with similar ports on the input devices .

PORTABLE ALARM

An embodiment of a portable alarm 600 is shown in Figure 6 of the accompanying drawings.

This is an additional input device that can be used in combination with the pluggable receiver to provide increased functionality to the apparatus . It may be accommodated within the base unit when not in use. The alarm comprises a splash or water proof hollow pendant 501 which supports a push button 502 that can be depressed by a patient if they are in difficulty. The button 502 is normally open and when depressed makes a contact to an electrical circuit (not shown) contained within the pendant. The electrical circuit generates a radio frequency signal that is transmitted by an antenna 503 integrated within a necklace from which the pendant is hung to the pluggable receiver. The signal is transmitted at a frequency of 433MHz or any other frequency that is compatible with the detecting range of the receiver of the base unit 100 or of the pluggable receiver 400.

Of course, the panic alarm need not be in the shape of a pendant and may alternatively be provided as a keyfob.

As for other input devices the alarm is provided with a unique code which is stored within memory in the pluggable receiver. The code is transmitted when the alarm button is operated to ensure the alarm does not conflict with other apparatus within radio range.

Figures 9 to 11 illustrate the use of the apparatus by a carer and the patient.

In Figure 9 the base unit is provided on a bedside table next to the patient. The handheld second unit is placed on a desk top next to the carer. This arrangement allows the patient and carer to hold a two-way communication and for the carer to monitor the temperature in the room.

In Figure 10 the base unit is now attached to a sensor mat allowing the carer to monitor the location of the patient from the second unit. Additionally the base unit includes functionality that permits telephone calls to be made to a third party over a telephone network. The carer may also make telephone calls via the second unit which is routed through the base unit.

Finally, Figure 11 illustrates the use of an optional telephone unit fitted with a presentation means that allows the carer to hold a two way conversation with the patient over a telephone network as well as monitor the well being of the patient from a built in presentation means. Figure 12(a) is a plan view and (b) is an elevational view of the telephone handset accessory. It comprises a main housing that accommodates a microphone and a loudspeaker and a liquid crystal display panel that presents data sent by the base unit 100 across the telephone network. This allows data such as room temperature and status of the optional sensor mat to be monitored by the carer from any remote location where a telephone call to a compatible network can be made.

It will, of course, be appreciated that in one arrangement the telephone accessory may be used as a substitute for the second handheld unit, allowing the handheld unit to be omitted altogether.

Claims

1. A reassurance monitoring apparatus for use by a carer to monitor a child or adult who requires reassurance, the apparatus comprising: a first assembly to be located in a room with the person being monitored including a microphone adapted to convert sounds generated by the patient into an audio signal, a transmitter adapted to transmit a first signal representative of the audio signal, a receiver adapted to receive a second signal and a speaker adapted to generate an acoustic signal from information in the second signal; a second assembly located by the carer and comprising a microphone adapted to convert sounds generated by the carer into an audio signal, a transmitter adapted to transmit a third signal representative of the audio signal, a receiver adapted to receive the first signal and a speaker adapted to generate an acoustic signal from information in the first signal; and characterised in that the first assembly further includes at least one sensor adapted to generate an output signal indicative of a sensed parameter, the signal being transmitted by the transmitter to the receiver of the second assembly and in which the second assembly includes presentation means arranged to present information indicative of the sensed parameter to the carer.

2. Apparatus according to claim 1 in which the transmitter and receiver of the first and second assemblies are adapted to respectively transmit and receive a radio frequency signal.

3. Apparatus according to claim 2 in which the radio frequency signal encodes the speech of the patient or carer and the sensed information as digitally encoded data.

4. Apparatus according to any preceding claim in which the first assembly and/or the second assembly are further adapted to make telephone calls over a telephone network.

5. Apparatus according to claim in which the first assembly is adapted to generate tone-dialling signals for transmission over the telephone network.

6. Apparatus according to any preceding claim in which the first assembly comprises a housing adapted to support the microphone and speaker and the transmitter/receiver.

7. Apparatus according to any one of claims 1 to 5 in which the first assembly comprises two discrete housings with a first housing supporting the transmitter/receiver and the second housing supporting the speaker and the micro-phone.

8. Apparatus according to any preceding claim in which the first assembly include one or more sensors adapted to monitor one or more conditions of the patient and/ or one or more sensors adapted to monitor surrounding environment.

9. Apparatus according to claim 8 in which the first assembly includes a temperature sensor adapted to measure the ambient temperature of the environment surrounding the sensor.

10. Apparatus according claim 8 or claim 9 in which the first assembly further includes a pressure sensor adapted to be operated by the patient.

11. The apparatus of claim 10 in which the pressure sensor comprises a pad which may be placed under the patient.

12. Apparatus according to any one of claims 8 to 11 in which the first assembly further includes a panic alarm switch or button which can be operated by the patient if they are in difficulty or require assistance.

13. Apparatus according to any preceding claim in which one or more of the or each sensors includes a transmitter and that the first assembly includes a dedicated receiver which is responsive to the signals issued by the transmitter(s) .

14. The apparatus of claim 13 as dependent on claim 12 in which the panic alarm comprises a housing shaped as a pendant which is worn by the patient on a necklace or chain that conceals or functions as an antenna for transmitting the sensed parameter (i.e. operation of the panic alarm) .

15. Apparatus according to any preceding claim in which the or each sensor may transmits a coded signal, the code being unique to each sensor and in which the receiver is adapted to only receive these coded signals.

16. Apparatus according to claim 15 in which the dedicated receiver includes an area of memory into which the codes may be stored.

17. Apparatus according to any preceding claim in which the second assembly comprises a hand held unit.

18. Apparatus according to any preceding claim in which the presentation means of the second assembly includes one or more visual displays or audible indicators.

19. Apparatus according to any preceding claim when dependent from claim 3 in which the second assembly includes a switch which when operated prevents the patient from using the first assembly as a telephone.

20. Apparatus according to any preceding claim when dependent from claim 3 in which a keypad is provided on the second unit whereby the carer can dial telephone numbers to make telephone calls .

21. Apparatus according to any preceding claim in which the second assembly includes an input device adapted to permit the carer to disable one or more of the input devices connected to or forming part of the first assembly.

22. Apparatus according to any preceding claim in which the second assembly is battery operated and further including a charging unit which is adapted to recharge the second unit.

23. A monitoring apparatus comprising: a first telephone unit capable of transmitting and receiving audio signals over a telephone network, a second telephone unit capable of transmitting and receiving audio signals over the telephone network, and in which the first unit is adapted to transmit data sensed by one or more sensors over the telephone network whilst the second unit includes a presentation means adapted to display the transmit data.