WO2006059915A1

WO2006059915A1 - Improvements in or relating to radio communications

Info

Publication number: WO2006059915A1
Application number: PCT/NZ2005/000315
Authority: WO
Inventors: Changburm Park; Anthony Daniel Hoffman; Anurasiri Gamalath; David John Mason; Johannes Maria Overtoom
Original assignee: Tait Electronics Limited
Priority date: 2004-12-02
Filing date: 2005-12-02
Publication date: 2006-06-08

Abstract

A two-way radio communication device (1) that operates over a two-way radio system via a radio transceiver module (3) and also has a cellular communication module (11) for operating over a cellular communication system. The device (1) having a controller (15) that automatically switches the device (1) to operate over the cellular communication system via the cellular communication module (11) when the device is outside the coverage of the two-way radio system and automatically switches the device back to operate over the two-way radio system when the device is within the coverage of the two-way radio system.

Description

IMPROVEMENTS IN OR RELATING TO RADIO COMMUNICATIONS

FIELD OF THE INVENTION

The present invention relates to radio communications and in particular, but not limited to, a radio communication device that is able to automatically switch between two-way radio communications and cellular communications depending on the location of the device.

BACKGROUND TO THE INVENTION

Two-way radio communication or Private Mobile Radio (PMR) is most commonly employed to maintain communications between personnel over a short distance, for example between security guards, courier staff and taxi drivers. Two-way radio communication devices can be as simple as walkie-talkies or more complex radio devices operating over trunked networks.

However, for applications requiring communications across considerable distances or where there are substantial physical obstacles, two-way radio communication is not suitable due to its limited operating range.

US Patent No. 5,553,117 discloses a communication device that includes an integral cellular telephone and two-way radio for use as an in- vehicle communication device. A user is able to manually select or switch between two-way radio communication and cellular telephone communication.

US Patent No. 6,415,158 discloses a dual mode mobile telephone that is able to be manually switched between a normal cellular operating mode and a two-way radio mode.

It is an object of the present invention to provide an improved radio communication device, or to at least provide the public with a useful choice. SUMMARY OF THE INVENTION

In a first aspect, the present invention broadly consists in a two-way radio communication device that operates over a two-way radio system via a radio transceiver module and also comprises: a cellular communication module for operating over a cellular communication system; and a controller that automatically switches the device to operate over the cellular communication system via the cellular communication module when the device is outside the coverage of the two-way radio system and automatically switches the device back to operate over the two-way radio system when the device is within the coverage of the two-way radio system.

Preferably, the cellular communication module and controller may be provided in a microphone module that is connected to the transceiver module. By way of example, the microphone module may comprise a housing that encloses the cellular communication module and controller, and the microphone module may further comprise a microphone, speaker and push-to-talk button that are integrated with the housing.

Preferably, the microphone module may comprise an attachment mechanism that is operable to securely attach the microphone module to clothing of a user. More preferably, the attachment mechanism may be an operable clip that is mounted to the microphone module and that is operable to clip the microphone module to clothing of a user.

Preferably, the device may further comprise an emergency switch that when triggered causes an emergency signal to be sent over the two-way radio system or cellular communication system to a base or other communication device. In one form, the emergency switch may be a manually operable switch that may be triggered manually by a user of the device. In another form, the emergency switch may be arranged to trigger automatically in response to predetermined movements of the device as sensed by a movement sensor. In yet another form, the emergency switch may be arranged to trigger automatically in response to a lack of movement of the device for a predetermined period of time as sensed by a movement sensor.

By way of example, the cellular communication module and controller may be provided in a microphone module that may be connected to the transceiver module by a connection cord that transfers signals between the microphone module and transceiver module, the emergency switch being located external to the microphone module.

Preferably, the connection cord extends from the microphone module and terminates at an attachment clip that is engageable with a complementary socket of the transceiver module and the emergency switch may be part of the attachment clip.

In one form, the device may comprise a location system that may be operable to obtain and provide representative location information relating to the physical location of the device. Preferably, the location system may comprise a Global Positioning System (GPS) module that is operable to receive and process GPS signals to determine the physical location of the device and generate representative location information. More preferably, the location system may further comprise a Radio Frequency Identification (RFID) module that is operable to communicate with external RFID devices whose physical locations are known to provide representative location information relating to the physical location of the device.

Preferably, the location system may be arranged to provide the representative location information to the controller upon request, the controller being arranged to send the representative location information over the two-way radio system or cellular communication system to a base or other communication device to enable the location of the device to be tracked. More preferably, the controller may be arranged to send the representative location information in response to operation of a request button of the device by a user or a request received over the two-way radio system or cellular communication system received from a base or other communication device. In one form, the two-way radio system may be a Private Mobile Radio (PMR) system operating on a tranked network. In another form, the two-way radio system may operate on a conventional two-way radio network.

In one form, the cellular communication module may comprise a General Packet Radio Service (GPRS) module that may be arranged to enable communication via GPRS over the cellular communication system. Preferably, the cellular communication system may be a Global System for Mobile Communications (GSM) network and the cellular communications module may further comprise a subscriber identification unit that provides subscriber identification information to enable access to the GSM network. More preferably, the subscriber identification unit may be a Subscriber Identity Module (SIM) card reader that may be arranged to extract subscriber identification information in the form of SIM data from a SIM card inserted into the reader to enable access to the GSM network.

Preferably, the controller may be arranged to automatically switch operation of the device from the two-way radio system to the cellular communication system when coverage from the two-way radio system drops below a predetermined signal strength threshold and automatically switch back to operation over the two-way radio system when coverage from the two-way radio system rises above the predetermined signal strength threshold. More preferably, the predetermined signal strength threshold may be the minimum level of signal strength required to maintain communication over the two- way radio system.

In a second aspect, the present invention broadly consists in a microphone device that is connectable to a radio transceiver that communicates voice data over a two-way radio system comprising: a housing for the microphone device components; microphone and speaker elements to enable communication of the voice data; a control button or buttons that are operable by a user to control the microphone and speaker elements to communicate the voice data; a cellular communication module that is operable to communicate the voice data over a cellular communication system; and a controller that controls whether the voice data is communicated over the two-way radio system via the radio transceiver or the- cellular communication system via the cellular communication module, the controller being arranged to automatically switch to communication over the cellular communication system when the radio transceiver is outside the coverage of the two-way radio system and automatically switch back to communicate over the two- way radio system when the radio transceiver is within the coverage of the two-way radio system.

Preferably, the control button(s) may comprise a push-to-talk button that may be operable by a user to control the microphone and speaker elements to communicate the voice data, the push-to-talk button being arranged to activate the microphone for voice data transmission when pressed and activate the speaker for voice data reception when not pressed.

Preferably, the housing of the microphone device may be connectable to the radio transceiver via a connection cord that transfers signals between the microphone device and radio transceiver, the connection cord extending from an input/output connection of the housing and terminating at an attachment clip that is engageable with a complementary socket of the radio transceiver.

In one form, the microphone device is mountable to clothing of a user. Preferably, an attachment mechanism is provided on the housing of the microphone device that is operable to securely attach the microphone device to clothing of a user. More preferably, the attachment mechanism may be an operable clip that may be mounted to the housing of the microphone device and that may be operable to clip the microphone device to clothing of a user.

Preferably, the microphone device may further comprise an emergency switch that when triggered causes an emergency signal to be sent over the two-way radio system or cellular communication system to a base or other communication device. In one form, the emergency switch may be a manually operable switch that may be triggered manually by a user of the device. In another form, the emergency switch may be arranged to trigger automatically in response to predetermined movements of the device as sensed by a movement sensor. In yet another form, the emergency switch may be arranged to trigger automatically in response to a lack of movement of the device for a predetermined period of time as sensed by a movement sensor.

Preferably, the device may comprise a location system that is operable to obtain and provide representative location information relating to the physical location of the device to the controller upon request, the controller being arranged to send the representative location information over the two-way radio system or cellular communication system to a base or other communication device to enable the location of the microphone device to be tracked. More preferably, the controller may be arranged to send the representative location information in response to operation of a request button of the microphone device by a user or a request received over the two-way radio system or cellular communication system received from a base or other communication device. In one form, the location system may comprise: a Global Positioning System (GPS) module that may be operable to receive and process GPS signals to determine the physical location of the microphone device and generate representative location information; and a Radio Frequency Identification (RFID) module that may be operable to communicate with external RFID devices whose physical locations are known to provide representative location information relating to the physical location of the microphone device.

In one form, the two-way radio system may be a Private Mobile Radio (PMR) system operating on a trunked network. In another form, the two-way radio system may operate on a conventional two-way radio network.

In one form, the cellular communication module may comprise a General Packet Radio Service (GPRS) module that may be arranged to enable communication via GPRS over the cellular communication system. Preferably, the cellular communication system may be a Global System for Mobile Communications (GSM) network and the cellular communications module may comprise a subscriber identification unit that provides subscriber identification information to enable access to the GSM network. More preferably, the subscriber identification unit may be a Subscriber Identity Module (SIM) card reader that may be arranged to extract subscriber identification information in the form of SIM data from a SIM card inserted into the reader to enable access to the GSM network.

Preferably, the controller may be arranged to automatically switch to communication over the cellular communication system when coverage from the two-way radio system drops below a predetermined signal strength threshold and automatically switch back to communicate over the two-way radio system when coverage from the two-way radio system rises above the predetermined signal strength threshold.

In a third aspect, the present invention broadly consists in a radio communication device that operates over a two-way radio system comprising: a Global Positioning System (GPS) module that is arranged to receive and process GPS signals to determine the physical location of the radio communication device and generate representative location information; a Radio Frequency Identification (RFID) module that is arranged to communicate with external RFID devices whose physical locations are known to obtain representative location information relating to the physical location of the radio communication device; and a controller that is operable to selectively obtain representative location information from either of the GPS or RFID modules for transmission over the two-way radio system.

Preferably, the controller may be arranged to obtain and transmit the representative location information over the two-way radio system in response to a request received from a base or other communication device over the two-way radio system.

Preferably, the controller may be arranged to obtain and transmit the representative location information over the two-way radio system in response to operation of a request button on the radio communication device by a user.

Preferably, the controller may be arranged to periodically obtain representative location information from the GPS module for periodic transmission over the two-way radio system. Preferably, the controller may be arranged to obtain representative location information from the RFID module in response to operation of a control button by a user, operation of the control button causing the RFID module to communicate with one or more of the external RFID devices to obtain the representative location information.

Preferably, the external RFID devices are transponders that each have a unique transponder identification (ID), the RFID module being arranged to extract the transponder ID from a transponder when in close proximity to that transponder, the transponder ID being associated with the known physical location of the transponder such that representative location information of the radio communication device can be determined. More preferably, the RFID module may be arranged to extract the transponder ID from a transponder by emitting radio frequency (RF) power toward the transponder in close proximity such that the transponder is activated to send its transponder ID back to the RFID module.

Preferably, the radio communication device may further comprise a cellular communication module for operating over a cellular communication system, the controller also being arranged to automatically switch the device to operate over the cellular communication system via the cellular communication module when the device is outside the coverage of the two-way radio system and automatically switch the device back to operate over the two-way radio system when the device is within the coverage of the two-way radio system. More preferably, the cellular communication module may comprise a General Packet Radio Service (GPRS) module that may be arranged to enable communication via GPRS over the cellular communication system, the cellular communication system being a Global System for- Mobile Communications (GSM) network and the cellular communications module further comprising a subscriber identification unit that provides subscriber identification information to enable access to the GSM network. In one form, the two-way radio system may be a Private Mobile Radio (PMR) system operating on a trunked network. In another form, the two-way radio system may operate on a conventional two-way radio network.

The term "coverage" as used in this specification and the accompanying claims refers to either geographically-set boundaries of a communications network or signal-strength boundaries beyond which the quality of communication using that network drops below an acceptable level, or both. It will be appreciated that the exact acceptable level will depend on the design of the communication network.

The term "module" as used in this specification and the accompanying claims may refer to a single component or a number of associated components depending on the context.

The term 'comprising' as used in this specification and claims means 'consisting at least in part of, that is to say when interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred forms of the radio communication device of the invention will now be described by way of example only and with reference to the accompanying drawings in which:

Figure 1 is a block diagram of the preferred form radio communications device; Figure 2 is a block diagram showing an example connectivity of the components in the preferred form radio communications device; Figure 3 is a perspective view of a prototype of the radio communications device;

Figure 4 is apian view of the radio communications device of Figure 3; and Figure 5 is a perspective view of the physical circuit layout in the radio communications device of Figure 3.

DETAILED DESCRIPTION OF PREFERRED FORMS

Referring to Figure 1, the preferred form radio communications device is shown generally by reference numeral 1. The device 1 comprises two main components - a microphone module 2 and a radio transceiver module 3. The transceiver module 3 may be carried in a carry case near the user's waist, attached to the user via a belt clip, or similar while the microphone module 2 is placed closer to the user's mouth and ears. In the preferred form shown, the microphone module 2 is formed as a lapel microphone. Alternatively it may be worn as a headset or incorporated in a helmet for example. The microphone module 2 and transceiver module 3 may be wired together via a connection cord or may communicate with each other utilising wireless technologies.

Alternatively the device of the invention may be a single integrated unit in one housing which is carried via a body or shoulder strap or in an external front pocket of a jacket just below the shoulder.

In the preferred form the transceiver module 3 includes a transceiver 4 which preferably operates over a PMR trunked network. A trunked network is one that allows users access to a pool of shared radio channels. When a call is placed, a channel from the pool is allocated to the call. Once the call is completed, the channel is returned back to the pool. Calls can be made in private and there is a more efficient use of radio network resources. The trunked radio technology is preferably based on the universal standard known as MPTl 327. It is also envisaged for the present invention to be used with simpler PMR systems, such as the registration and licence-free protocol of PMR466. The transceiver module 3 also includes a battery pack 5. It will be appreciated that the device does not necessarily have to operate over a trunked two-way radio network. Alternative forms of the device may operate over a conventional two-way radio network or any other type of two-way radio network or system. The- microphone module 2 includes a microphone 6 and a speaker 7 and a push-to-talk (PTT) button 8. The PTT button 8 is operable by a user to control the microphone 6 and speaker 7 elements of the microphone module 2 to enable the communication of voice. For example, the PTT button 8 is arranged to activate the microphone 6 for voice transmission when pressed and activate the speaker 7 for voice reception when not pressed.

The device may also comprise an emergency switch which when triggered or actuated will transmit an emergency signal from the device 1 to a base or other communication device. It will be appreciated that the emergency switch may be a manually operable switch, such as a button 9 located either on the microphone module 2 or external to the microphone module on the connection cord or some other part of the device, that may be activated by a user when they are in trouble or danger. Alternatively or additionally, the emergency switch may be arranged to trigger automatically in response to predetermined movements or lack of movement of the device or the user carrying or wearing the device as sensed by a sensor. For example, the emergency switch may be in the form of a man-down switch that is automatically activated if the user falls down, either due to an accident or an assault, or if the user is still and lacks movement for a predetermined period of time due to being knocked unconscious or being incapacitated in some other way. Any suitable tilt switch or movement detector or sensor may be used, employing for example a ball-bearing or the like that moves to make or break electrical contact depending on orientation.

When the device 1 is within the coverage of the two-way radio network, communication to and from device 1 is carried over the two-way radio network through radio antenna 10. The device 1 is preferably set-up to communicate (voice and/or data) over the two- way radio network by default.

When the device 1 goes beyond the coverage of the two-way radio network, the device switches operation to communicate over a cellular system via a cellular communication module. It will be appreciated that any cellular system or network may be used, such as systems based on TDMA, CDMA, GSM or any other protocol. Further, various cellular communications modules may be utilised depending on the particular cellular communications network selected. By way of example, the preferred form device 1 utilises a GPRS module 11 to enable cellular communications (voice and/or data) to be sent using GPRS technology. The cellular communication system is compatible with the transmission technology of the General Packet Radio Service (GPRS), which provides the device 1 with the capability to send data over the Internet. Provided the device is within coverage of the cellular system or network, information can be sent or received via GPRS as the need arises. There is no requirement for the device to dial-up for access to the Internet. This "always connected" feature is desirable as it provides a seamless connectivity to the Internet.

As with most cellular networks, the user will have to provide a unique subscriber identification to obtain access to the cellular network. A Subscriber Identity Module (SIM) is used in Global System for Mobile Communications (GSM) networks for this purpose. Therefore, to communicate using GPRS over GSM, the device 1 must be able to provide SIM data. For this purpose, a SIM card reader 12 is provided that is arranged to extract SIM data from a SIM card inserted in the reader.

A controller 15 is arranged to monitor the device's coverage by the two-way radio network. The controller is arranged to automatically switch operation of the device from the two-way radio system to the cellular network and in the preferred form communication via GPRS over GSM, when signal strength on the two-way radio system falls below a predetermined threshold, and to switch operation of the device back to two-way radio when the device returns to within coverage at acceptable signal strength for the two-way radio system. By way of example, the predetermined signal strength threshold may be set at the minimum level of signal strength required to maintain communication over the two-way radio system without drop-out. Thus, as a user such as a security guard moves within a large building or mall for example where two-way radio signal strength may be limited, the device will maintain communication with base over the cellular network. Communications are redirected from trunked radio to the cellular network so that the user maintains contact with the base when outside coverage by the trunked radio network, by automatically switching to the cellular network. The controller 15 may be a programmable device, such as a microprocessor, microcontroller, programmable logic controller or any other suitable electronic controller device.

The preferred form device is also provided with a location system that is operable to obtain and provide representative location information relating to the physical location of the device. The location system provides functionality that enables the device to report to a base or other communication device its location so that the base or person using the other communication device may monitor and track the location of the device or more particularly of a person carrying the device. For example, in security applications, a base may wish to monitor the location of all of its security personnel to maximise personnel distribution or for safety. In the preferred form, the location system is operated by the controller 15 and the location system provides representative location information to the controller upon request from the controller. The request from the controller 15 may be initiated in response to operation of a request button on the device 1 by a user or a request signal received over the two-way radio system or cellular communication system from a base or other communication device. Once the controller 15 receives the representative location information it arranges the transmission of the location data over the two-way radio system or cellular communication system to a base or other communication device.

In the preferred form, the location system of the device 1 comprises a Global Positioning System (GPS) antenna 13 and GPS module 14. The GPS module 14 receives and processes GPS signals received by the GPS antenna 13 to determine the physical location of the device and generate representative location information or data. The GPS module 14 is coupled to the controller 15, which receives and stores the relevant output data from the GPS module. Upon receipt of an interrogation signal, the extracted information is sent to base over the two-way radio network if the device is in range of that network, or over the cellular network and/or Internet through GPRS module 11. Alternatively the device may be arranged to transmit location information to base periodically without interrogation. As long as the device 1 is in range of receiving a GPS signal, the location of device 1 can be accurately determined. If the device 1 is expected to be utilised in areas where GPS signal reception is weak, such as within buildings, the location system of the device 1 may also comprise a radio frequency identification (RFID) functionality as a back-up location tracking system to GPS. In particular, the location system may additionally include an RFID module that is operable to communicate with external RFID devices whose physical locations are known to provide representative location information. For this dual location system, the controller is operable to selectively obtain representative location information from either of the GPS or RFID modules for transmission over the two-way radio system or cellular communication system. In particular, the controller may be arranged to obtain representative location information from the GPS module by default, but to then obtain representative location information from the RFID module upon operation of a control button by a user.

By way of example, areas within a building may be provided with radio transmitters or RFID transponders that are each able to transmit a unique transponder identification (ID) via an RF signal. The transponders may be located in distinct areas, such as at the entrance of rooms within the building. Device 1 is provided with an RFID module or reader 16 that is arranged to extract the transponder ID from a transponder when in close proximity to the transponder. For example, the RFID module of the device 1 may be operable, by a button or other control signal, to emit a burst of RF power toward a transponder when in close proximity to thereby activate the passive transponder to transmit its transponder ID via an RF signal. The RFID module of the device 1 receives the signal, extracts the transponder ID and then forwards it back to base either via the two-way radio network or the cellular network. The proximity required between the device and each transponder for effective operation will depend on the design parameters and components, but could be as small as a few centimetres or as large as a few meters or more.

With such a configuration, the base would have a database of each transponder ID and its respective physical location. By comparing the unique transponder ID forwarded by the device 1 and the information in the database, the location of device 1 can be determined. The more transponders used, the more accurate the determination of the location of the device 1.

It will be appreciated that the RFID location determination system may be implemented in alternative ways. For example, an opposite arrangement may be implemented whereby instead of having an RFID reader 16 in the device 1 interacting with external transponders, an RFID transmitter may be provided in the device that interacts with external radio frequency receivers. In particular, the RFID transmitter may be arranged to transmit a unique identification (ID) when in proximity to an external radio frequency receiver. Like the transponders, the radio frequency receivers may be arranged throughout a certain area and would be capable of forwarding the received unique ID from the device 1 back to a base. Again, the base will ideally have a database in which the radio frequency receivers are catalogued with their physical location. Based on the radio frequency receiver which forwarded the ID, the location of device 1 can be determined.

Referring to Figure 2, an example circuit layout of the microphone module 2 is shown. It is emphasised that this circuit layout is only an example layout and that the invention does not necessitate this precise layout or all of the shown components.

The circuit layout is divided into two main Printed Board Assemblies (PBAs) — the location/control PBA 19 and the cellular communication PBA 20, each shown enclosed by dashed lines. The location/control PBA 19 allows for the connection of the radio communication components previously described, namely the microphone 6, speaker 7 and PTT button 8. As will be described in greater detail below, this allows the location/control PBA 19 to direct the communications coming into and out of the components according to the mode of operation.

External to the location/control PBA 19, the communication components are connected to the transceiver module (not shown) through the EMI filter 21 and the input/output connector 22. The EMI filter 21 essentially protects the circuit against high voltage electric discharges and against strong electromagnetic fields, picked up via Electro- Magnetic Interference (EMI). As previously stated, an emergency or man-down switch 23 is preferably provided external to the radio microphone. The man-down switch 23 is thus connected to the location/control PBA 19 via connector 22.

The location/control PBA 19 is also provided with a GPS module 14 and a GPS antenna 13. This allows location tracking of the device or of a user in possession of the device. A back-up battery 24 is provided to ensure the GPS module 14 does not lose its almanac after a power-down, turn-off or disconnect from the battery. The almanac resides in volatile memory in the GPS module 14 and contains the last recorded positioning data to ensure fast lock-on upon power up.

The device in Figure 2 is also provided with an RFID location tracking feature. The RFID module 25, through the antenna 26, is able to transmit and/or receiver location tracking information via interaction with external RFID devices fixed in various locations as described previously.

Referring to the cellular communication PBA 20, the GPRS module 11 and SIM card reader 12 as previously described are shown. Communication between the cellular communication PBA 20 and the location/control PBA 19 is done via interface 27 and EMI filter 28. The EMI filter 28 is a preferable addition to ensure the device is protected against handling damage during manufacturing, assembly, testing and repair in the field. The EMI filter 28 may also protect the circuitry on one PBA from unwanted signal, generated on the other PBA. However the EMI filter 28 is not an essential feature and may be omitted.

The various elements of the device operate under low voltages, which result in a substantial power loss when regulated from linear regulators. In the preferred form, to overcome this problem and to optimise battery life the supply management on the cellular communication PBA 20 comprises a number of components to regulate and minimise power consumption from the battery. A shielded DC-DC converter 42, also called a Buck Regulator, converts the battery voltage to the 3.3V required to operate the GPRS module 11 and the SIM card reader 12. The GPRS module requires short pulses of high current for its transmissions, and to suppress the heavy current load the GPRS module 11 demands components 30 to 35 are provided. To avoid overloading the supply circuitry in the device the GPRS module 11 derives its current from a super capacitor 35. Upon power-up, when the super cap is without charge, the battery will need to supply the current to charge the capacitor 35. To ensure the supply circuitry in the device does not overload, a current sensor 31 drives a charge control 32 so that a switch 33 is opened just enough for the appropriate charge current to flow to the super capacitor 35. The discharges by the GPRS module 11 are compensated via the same circuitry. The charge control 32 uses the output from a switched mode power supply 29 to compare the voltage on the capacitor with a 3.3V-reference 34 to ensure that the voltage remains within the specification window of the GPRS module 11. Lastly the switch 33 is completely turned off when the battery voltage is considered too low by the battery sensor 30.

The microphone module 2 is controlled by the controller 15, which is shown in the form of a Micro Controller Unit (MCU). As shown in Figure 2 the controller 15 is connected to the GPS module 14 through a multiplexer 36, the RFID module 25 and the GPRS module 11 through the inter board connector 27 and EMI filter 28. The controller 15 is also connected to the transceiver module 3 and the communication components (microphone 6, speaker 7 etc.) via the multiplexer 36.

The controller 15 has two serial ports. One of the ports is connected to the GPRS module 11, while the other is connected to the GPS module 14, the radio transceiver 3 and the RFID module 25 via the multiplexer 36. The default setting of the multiplexer 36 is in connection with the GPS module 14, which updates the controller 15 with new position data once per second.

The controller 15 is responsible for changing the multiplexer 36 path. In terms of location-determination, when the device receives a poll request for the position information, the data causes an interrupt, which forces the controller 15 to change the path of the multiplexer 36 to connect to the radio network. Data exchanged over the serial port then results in a transmission of the position data over the trunked radio network. When the device loses reception of the radio service, it sends a command to the controller 15 to establish a cellular and/or Internet connection. A poll request for position information via the cellular/Internet network is dealt with in similar fashion, although the controller 15 does not have to change the path of the multiplexer 36 as the GPRS module 11 has its own serial path.

As mentioned above, the controller 15 is also coupled to the RFID components. In the embodiment where the pressing of a button is required to initiate RFID transmission/reception, the pressing of that button will cause the controller 15 to change the path of the multiplexer 36 to the RFID module 25 in Figure 2. Data is then exchanged between the RFID module 25 and the controller 15. Following this, the controller 15 either processes/forwards the data via the two-way radio system or via the cellular/Internet system through the GPRS module 11.

Figures 3 to 5 show an example of how the circuit shown in Figure 2 can be incorporated within a lapel microphone of a two-way radio. The lapel microphone, shown generally as 37, is attached to the transceiver module (not shown) by coil cord 38. The connection between the cord 38 and the transceiver module is made using an attachment clip or connector 39 that engages a complementary socket of the transceiver module.

In use, the lapel microphone 37 is clipped onto a user's lapel or any other area of a user's clothing using operable clip 40 so as to locate the microphone near the user's ears and mouth. It will be appreciated that any other appropriate attachment mechanism may alternatively be used to securely attach the microphone 37 to clothing of a user. The cord 38 then connects the lapel microphone 37 via attachment clip 39 to a transceiver module that would normally be carried near the user's waist. In the form shown, the emergency switch (23 in Figure 2) is provided on the attachment clip 39, but it could be located on any other part of the device.

Figure 4 shows the lapel microphone 37 with its cover removed, showing the cellular communication PBA 20. In Figure 5, both location/control PBA 19 and cellular communication PBA 20 are shown. Most clearly visible in this view are the Super Cap 35, GPS antenna 26, GPS module 14 and the SIM card reader 12.

The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention as defined by the accompanying claims.

Claims

1. A two-way radio communication device that operates over a two-way radio system via a radio transceiver module and also comprises: a cellular communication module for operating over a cellular communication system; and a controller that automatically switches the device to operate over the cellular communication system via the cellular communication module when the device is outside the coverage of the two-way radio system and automatically switches the device back to operate over the two-way radio system when the device is within the coverage of the two-way radio system.

2. A two-way radio communication device according to claim 1 wherein the cellular communication module and controller are provided in a microphone module that is connected to the transceiver module.

3. A two-way radio communication device according to claim 2 wherein the microphone module comprises a housing that encloses the cellular communication module and controller, the microphone module further comprising a microphone, speaker and push-to-talk button that are integrated with the housing.

4. A two-way radio communication device according to claim 2 or claim 3 wherein the microphone module comprises an attachment mechanism that is operable to securely attach the microphone module to clothing of a user.

5. A two-way radio communication device according to claim 4 wherein the attachment mechanism is an operable clip that is mounted to the microphone module and that is operable to clip the microphone module to clothing of a user.

6. A two-way radio communication device according to any one of the preceding claims wherein the device further comprises an emergency switch that when triggered causes an emergency signal to be sent over the two-way radio system or cellular communication system to a base or other communication device.

7. A two-way radio communication device according to claim 6 wherein the emergency switch is a manually operable switch that may be triggered manually by a user of the device.

8. A two-way radio communication device according to claim 6 wherein the emergency switch is arranged to trigger automatically in response to predetermined movements of the device as sensed by a movement sensor.

9. A two-way radio communication device according to claim 6 wherein the emergency switch is arranged to trigger automatically in response to a lack of movement of the device for a predetermined period of time as sensed by a movement sensor.

10. A two-way radio communication device according to any one of claims 6-8 wherein the cellular communication module and controller are provided in a microphone module that is connected to the transceiver module by a connection cord that transfers signals between the microphone module and transceiver module, the emergency switch being located external to the microphone module.

11. A two-way radio communication device according to claim 10 wherein the connection cord extends from the microphone module and terminates at an attachment clip that is engageable with a complementary socket of the transceiver module and the emergency switch is part of the attachment clip.

12. A two-way radio communication device according to any one of the preceding claims wherein the device comprises a location system that is operable to obtain and provide representative location information relating to the physical location of the device. ■ 13. A two-way radio communication device according to claim 12 wherein the location system comprises a Global Positioning System (GPS) module that is operable to receive and process GPS signals to determine the physical location of the device and generate representative location information.

14. A two-way radio communication device according to claim 13 wherein the location system further comprising a Radio Frequency Identification (RFID) module that is operable to communicate with external RFID devices whose physical locations are known to provide representative location information relating to the physical location of the device.

15. A two-way radio communication device according to any one of claims 12-14 wherein the location system is arranged to provide the representative location information to the controller upon request, the controller being arranged to send the representative location information over the two-way radio system or cellular communication system to a base or other communication device to enable the location of the device to be tracked.

16. A two-way radio communication device according to claim 15 wherein the controller is arranged to send the representative location information in response to operation of a request button of the device by a user or a request received over the two-way radio system or cellular communication system received from a base or other communication device.

17. A two-way radio communication device according to any one of the preceding claims wherein the two-way radio system is a Private Mobile Radio (PMR) system operating on a trunked network.

18. A two-way radio communication device according to any one of claims 1-16 wherein the two-way radio system operates on a conventional two-way radio network. 19. A two-way radio communication device according to any one of the preceding claims wherein the cellular communication module comprises a General Packet Radio Service (GPRS) module that is arranged to enable communication via GPRS over the cellular communication system.

20. A two-way radio communication device according to any one of the preceding claims wherein the cellular communication system is a Global System for Mobile Communications (GSM) network and the cellular communications module further comprises a subscriber identification unit that provides subscriber identification information to enable access to the GSM network.

21. A two-way radio communication device according to claim 20 wherein the subscriber identification unit is a Subscriber Identity Module (SIM) card reader that is arranged to extract subscriber identification information in the form of SIM data from a SIM card inserted into the reader to enable access to the GSM network.

22. A two-way radio communication device according to any one of the preceding claims wherein the controller is arranged to automatically switch operation of the device from the two-way radio system to the cellular communication system when coverage from the two-way radio system drops below a predetermined signal strength threshold and automatically switch back to operation over the two-way radio system when coverage from the two-way radio system rises above the predetermined signal strength threshold.

23. A two-way radio communication device according to claim 22 wherein the predetermined signal strength threshold is the minimum level of signal strength required to maintain communication over the two-way radio system.

24. A microphone device that is connectable to a radio transceiver that communicates voice data over a two-way radio system comprising: a housing for the microphone device components; microphone and speaker elements to enable communication of the voice data; a control button or buttons that are operable by a user to control the microphone and speaker elements to communicate the voice data; a cellular communication module that is operable to communicate the voice data over a cellular communication system; and a controller that controls whether the voice data is communicated over the two- way radio system via the radio transceiver or the cellular communication system via the cellular communication module, the controller being arranged to automatically switch to communication over the cellular communication system when the radio transceiver is outside the coverage of the two-way radio system and automatically switch back to communicate over the two-way radio system when the radio transceiver is within the coverage of the two-way radio system.

25. A microphone device according to claim 24 wherein the control button(s) comprises a push-to-talk button that is operable by a user to control the microphone and speaker elements to communicate the voice data, the push-to-talk button being arranged to activate the microphone for voice data transmission when pressed and activate the speaker for voice data reception when not pressed.

26. A microphone device according to claim 24 or claim 25 wherein the housing of the microphone device is connectable to the radio transceiver via a connection cord that transfers signals between the microphone device and radio transceiver, the connection cord extending from an input/output connection of the housing and terminating at an attachment clip that is engageable with a complementary socket of the radio transceiver.

27. A microphone device according to any one of claims 24-26 wherein the microphone device is mountable to clothing of a user.

28. A microphone device according to claim 27 wherein an attachment mechanism is provided on the housing of the microphone device that is operable to securely attach the microphone device to clothing of a user. 29v A microphone device according to claim 28 wherein the attachment mechanism is an operable clip that is mounted to the housing of the microphone device and that is operable to clip the microphone device to clothing of a user.

30. A microphone device according to any one of claims 24-29 wherein the microphone device further comprises an emergency switch that when triggered causes an emergency signal to be sent over the two-way radio system or cellular communication system to a base or other communication device.

31. A microphone device according to claim 30 wherein the emergency switch is a manually operable switch that may be triggered manually by a user of the device.

32. A microphone device according to claim 30 wherein the emergency switch is arranged to trigger automatically in response to predetermined movements of the device as sensed by a movement sensor.

33. A microphone device according to claim 30 wherein the emergency switch is arranged to trigger automatically in response to a lack of movement of the device for a predetermined period of time as sensed by a movement sensor.

34. A microphone device according to any one of claims 24-33 wherein the device comprises a location system that is operable to obtain and provide representative location information relating to the physical location of the device to the controller upon request, the controller being arranged to send the representative location information over the two-way radio system or cellular communication system to a base or other communication device to enable the location of the microphone device to be tracked.

35. A microphone device according to claim 34 wherein the controller is arranged to send the representative location information in response to operation of a request button of the microphone device by a user or a request received over the two-way radio system or cellular communication system received from a base or other communication device.

36. A microphone device according to claim 34 or claim 35 wherein the location system comprises: a Global Positioning System (GPS) module that is operable to receive and process GPS signals to determine the physical location of the microphone device and generate representative location information; and a Radio Frequency Identification (RFID) module that is operable to communicate with external RFID devices whose physical locations are known to provide representative location information relating to the physical location of the microphone device.

37. A microphone device according to any one of claims 24-36 wherein the two-way radio system is a Private Mobile Radio (PMR) system operating on a trunked network.

38. A microphone device according to any one of claims 24-36 wherein the two-way radio system operates on a conventional two-way radio network.

39. A microphone device according to any one of claims 24-38 wherein the cellular communication module comprises a General Packet Radio Service (GPRS) module that is arranged to enable communication via GPRS over the cellular communication system.

40. A microphone device according to any one of claims 24-39 wherein the cellular communication system is a Global System for Mobile Communications (GSM) network and the cellular communications module comprises a subscriber identification unit that provides subscriber identification information to enable access to the GSM network.

41. A microphone device according to claim 40 wherein the subscriber identification unit is a Subscriber Identity Module (SIM) card reader that is arranged to extract ■subscriber- identification information in the form of SIM data from a SIM card inserted into the reader to enable access to the GSM network.

42. A microphone device according to any one of claims 24-41 wherein the controller is arranged to automatically switch to communication over the cellular communication system when coverage from the two-way radio system drops below a predetermined signal strength threshold and automatically switch back to communicate over the two-way radio system when coverage from the two-way radio system rises above the predetermined signal strength threshold.

43. A radio communication device that operates over a two-way radio system comprising: a Global Positioning System (GPS) module that is arranged to receive and process GPS signals to determine the physical location of the radio communication device and generate representative location information; a Radio Frequency Identification (RFID) module that is arranged to communicate with external RFID devices whose physical locations are known to obtain representative location information relating to the physical location of the radio communication device; and a controller that is operable to selectively obtain representative location information from either of the GPS or RFID modules for transmission over the two-way radio system.

44. A radio communication device according to claim 43 wherein the controller is arranged to obtain and transmit the representative location information over the two- way radio system in response to a request received from a base or other communication device over the two-way radio system.

45. A radio communication device according to claim 43 or claim 44 wherein the controller is arranged to obtain and transmit the representative location information over the two-way radio system in response to operation of a request button on the radio communication device by a user. 46. A radio communication device according to any one of claims 43-45 wherein the controller is arranged to periodically obtain representative location information from the GPS module for periodic transmission over the two-way radio system.

47. A radio communication device according to any one of claims 43-46 wherein the controller is arranged to obtain representative location information from the RFID module in response to operation of a control button by a user, operation of the control button causing the RFID module to communicate with one or more of the external RFID devices to obtain the representative location information.

48. A radio communication device according to any one of claims 43-47 wherein the external RFID devices are transponders that each have a unique transponder identification (ID), the RFID module being arranged to extract the transponder ID from a transponder when in close proximity to that transponder, the transponder ID being associated with the known physical location of the transponder such that representative location information of the radio communication device can be determined.

49. A radio communication device according to claim 48 wherein the RFID module is arranged to extract the transponder ID from a transponder by emitting radio frequency (RF) power toward the transponder in close proximity such that the transponder is activated to send its transponder ID back to the RFID module.

50. A radio communication device according to any one of claims 43-49 wherein the radio communication device further comprises a cellular communication module for operating over a cellular communication system, the controller also being arranged to automatically switch the device to operate over the cellular communication system via the cellular communication module when the device is outside the coverage of the two-way radio system and automatically switch the device back to operate over the two-way radio system when the device is within the coverage of the two-way radio system. 51. A microphone device according to claim 50 wherein the cellular communication module comprises a General Packet Radio Service (GPRS) module that is arranged to enable communication via GPRS over the cellular communication system, the cellular communication system being a Global System for Mobile Communications

(GSM) network and the cellular communications module further comprising a subscriber identification unit that provides subscriber identification information to enable access to the GSM network.

52. A radio communication device according to any one of claims 43-51 wherein the two-way radio system is a Private Mobile Radio (PMR) system operating on a trunked network.

53. A radio communication device according to any one of claims 43-51 wherein the two-way radio system operates on a conventional two-way radio network.