GB2393075A

GB2393075A - Method and apparatus for selectively disabling mobile electronic equipment

Info

Publication number: GB2393075A
Application number: GB0220989A
Authority: GB
Inventors: Donald Power
Original assignee: NEC Technologies UK Ltd
Current assignee: NEC Technologies UK Ltd
Priority date: 2002-09-10
Filing date: 2002-09-10
Publication date: 2004-03-17
Anticipated expiration: 2022-09-10
Also published as: GB2393075B; GB0220989D0

Abstract

There is provided a method of selectively disabling an operation of a mobile electronic device having a location determination system and a counting system which comprises the steps of selectively identifying a preferred home location of the device and determining the current location of the device and in the event that the current location is different from the home location operating an appropriate counter of the counting system which on determination of an appropriate predetermined event the counter is varied by a preset value such that the device is subsequently at least partially disabled if the counter reaches or passes a preset cut-off value. There is further provided a mobile electronic device utilising such a method as a security system to render the device inoperable in the event of the occurrence of a number of pre-determined events when the device is remote from its home location, wherein a pre-determined event may be the expiry of a present period fo time, the making of an outgoing call, the expiry of a present period fo time during which the device is being operated, or the event may relate to the cost of the services used by the phone.

Description

Method and Apparatus tor Selectively Disahlin Mobile Electronic Equipment

The present invention relates to mobile electronic devices of the type which have 5 means Jor detecting relative location and, more specifically, to a method for selectively disabling such a device if its use or possession deemed to be unauthorized, and a device employing such method, thereby providing a theft deterrent for such mobile electronic equipment.

1() The rapid progress in recent electronic development, particularly within the field

of computers, mobile communication technology and smart-card technology, has resulted in the design and production of a high number of lightweight mobile devices which have not only improved the availability and portability of such technology but have also created a number of expensive articles which, due to 15 their compact and lightweight design, are highly desirable to thieves due to their ease of concealment and disposal. The subsequent increase in theft of such products has now prompted both manufacturers and government bodies to seek improved means of preventing and deterring the theft of this type of portable electronic equipment.

_() In the case of portable and laptop computers, such devices can be provided with appropriate password locks but quite often these must be manually input each time the computer is set down in order to "lock" the computer- an operation which is

often overlooked (either inadvertently or deliberately) by the user, thus making the deterrent factor dependent on the actual owner of the device. By providing systems that automatically activate a password lock, then this problem can be alleviated but at the inconvenience ot the user who may become frustrated at the 5 continuous need to unlock their equipment, which often results in this automatic lock function again being deliberately disabled by the owner. As such, the use of such password locks are thus ineffective as a theft deterrent system due to the inconvenience to the user often resulting in such systems being deactivated.

It) Within the field ot mobile communications, manufacturers have historically

addressed the problem by attempting to render the phones and other devices useless to a thief or unauthorized user. Current systems involve locking such phones to their removable SIM cards (Subscriber Identity Module) whereby the SIM card PIN number (Personal Identification Number, also referred to as CHVl 15 - Card Holder Verification 1) can be enabled so that a particular phone with a pre determined SIM card can only be activated by the appropriate code. However, again many users are reluctant to be inconvenienced by the need of entering PIN codes each time they power up their mobile communication devices, thereby negating the effectiveness of the security feature which again is often deliberately 2() disabled by the owner. Thus, whilst security systems are currently available for electronic devices, they usually require a high intensity user interaction making them undesirable and often unused, thus rendering such systems impotent as a large scale theft deterrent for this type of equipment.

It is therefore an object of the present invention to provide a method for selectively disabling operation of a mobile electronic device, and a mobile electronic device employing such a method, which alleviates the aforementioned 5 problems hl a comparatively unobtrusive manner and requiring minimal user interaction. According to the present invention there is now provided a method of selectively disabling operation of a mobile electronic device having a location determination 10 system and a counting system, comprising the steps of selectively identifying at least one preferred home location of the electronic device; determining current location of the device; L5 selling a counter of the counting system to a pre-determined initial value when the device determines. the home location; activating the counting system when the location determination system identifies a location tor the device different from the at least one preferred home location; 2() varying the counter by a preset value in response to a pre-determined event when counting system is activated; and at least partially disabling the device if the counter reaches or passes a preset cut-off value.

In this manner, should the electronic device be removed from its home location then an appropriate counting sequence will be initiated automatically, without the need ot input from the user, such that the device utilising such a method will have 5 a limited operational lifespan before being at least partially disabled.

Preferably the counter will be reset to the pre-determined initial value when the device determines the home location, serving to automatically reset this type of security system when the device returns to its home location as indicative of the 1() device remaining in the possession of its legitimate owner. It is also preferred that the counting system is deactivated when the device determines the home location, so that the authorised user is continuously free to use the system at home.

By appropriate setting of the counter system, the user may continue using the 15 device 1or a pre-determined period before the counter reaches the preset cut-off value, whereby the pre-determined period is calculated so that, in normal operation, the operator is able to return to their home location before expiry of such period, thereby automatically resetting the counter. Thus the system provides a security mechanism which, in exceptional circumstances, whereby the 2() user either varies their normal routine or is indicative that the phone has been mis appropriated, will selectively disable the device.

is Usually, the pre-deterrnined event is the expiry of a preset period of time, which may be calculated in seconds, hours or minutes or any determined time period interval. 5 In certain embodiments of this invention, the location of the device is periodically determined automatically, by the device being appropriately programmed to undertake this process step at designated time intervals, or even to be monitored constantly. Alternatively, or in combination, the location may be determined in response to occurrence of the pre-detenmined event.

1(') Where the device incorporates an appropriate GPS system, the location determination system preferably determines the device location by the detection and analysis of signals from Global Positioning Satellites, allowing the home location to be determined by appropriate geographical reference.

Preferably, the device may comprise a mobile communication device, especially a mobile phone. Here the pre-detennined event may comprise the making of an outgoing call. or, alternatively (or again in combination), the expiry ot a preset period ol time during which the communication device is being operated during 2() either or both of the making or receiving a call. This allows the phone to be used either for a preset number of calls or allowing any number of calls up to a preset total duration.

Still furtller, the prc-determined event may alternatively comprise the determination of a pre-detennined cost value associated with a particular operation incurred during the making of a call. Thus, where the communication device not only determines the time of usage but is also able to calculate the cost 5 incurred by such usage, the counter can be activated so as to monitor cost of using the device, which itself may also be dependent on location.

For such communication devices, it is preferable that the location determination system uses mobile communications technology to determine at least one of Cell 1() Identity, Location Area Code, Mobile Country Code Mobile Network Code or Network Measurement results to identify the determined location. Alternatively, for such communication devices incorporating an appropriate GPS system, location may be determined by detection and analysis of appropriate signals emanating from appropriate satellites to determine relative geographical location, 15 either instead of or in combination of location determination using the aforementioned mobile communication technology data.

Usually, the pre-determined initial value of the counter is set greater than zero and the counter is varied by the subtraction of the preset value upon detection of a pre 2(:) determined event, whereby disabling of the device occurs when the counter reaches zero or a negative value, effectively providing a countdown system.

Alternatively, the counter may be set initially to zero and subsequently varied by

the addition of a preset value upon detection of a pre-determined event, wherein disablement occurs when a known cut off value is then reached by the counter.

Preferably, the step of disabling the device may comprise electronically locking its 5 operation or, alternatively or in combination with such electronic locking, mechanically preventing operation of the device, such as triggering operation of a manual restraint mechanism to specifically prevent actuation of mechanical buttons or switches of said device.

1() Where the device is capable of being electronically locked, the step of electronically locking the device is preferably reversible by input of a pre-selectcd cancel instruction, usually as a alphanumeric code.

In specific embodiments of the present invention, the step of reversing the 15 electronic locking of the device by input of cancel instruction may be limited to being dependent on determination of the home location. Thereby, should an unauthorized user not only acquire the device, but also the cancel instruction, the device would become inoperative if the user was unaware of the home location.

20 Preferably, input of the cancel instruction may reset the counter to the pre determined initial value, thereby re-initialising its function.

It is also preferred that the device may be allocated a plurality of preferred home locations, tor example, representative of home and work locations.

Furthermore, the method according to the preset invention may be selectively 5 deactivated by operation of a pre-selected disable instruction, usually comprising the input of a pre-determined electronic deactivation code.

It is preferred that the step of at least partially disabling the device will usually comprise disabling of pre-selected functions of the device, thereby allowing the It) device to remain operational for emergency use.

In a further enhancement of this invention, the method may also comprise generating an output signal upon the counter reaching the preset cut-off value, whereby, preferably, at least one of an audible, visual or mechanical warning is 15 generated on determination of the output signal, both serving to notify an authorised user that such a security feature requires to be reset and also providing means ot identifying a device that may have been misappropriated.

Further according to the present invention there is also provided a mobile 20 electronic device having a location determination system, a counting system having a counter, a memory system for retaining a code indicative of at least one preferred home location for the device and a security mechanism for selectively disabling the device upon receipt of a pre-selected signal, wherein the counter is

automatically reset to a prc-determined initial value upon detection of location having a location code comparable to the code of the preferred home location, whereby the counting system its responsive to a predetermined event so as to vary the value of the counter by a preset value as a result thereof when the location 5 determination system also determines a location different to the preferred home location, the counting system comprising means for generating the pre-selected signal upon variation of the counter to a preset cut-off value.

Preferably, the location determination system will comprise at least one of a Cell 1() Identity system, a Location Area Code identification system, a Mobile Country Code identification system, a Mobile Network Code identification system or a Network Measurement system to identify the determined location using mobile communication technology.

15 It is also preferred that the device further comprises a keypad and a security mechanism override circuit responsive to a pre-determined code entered on the keypad to reset the security mechanism and reset the counter.

One such device may comprise a mobile communication device, especially a 2() mobile telephone.

There will now be described, by way of example only, several preferred embodiments of the present invention with reference to the accompanying illustrative drawings in which: 5 Figure I is a flowchart showing a procedural embodiment according to the present invention; and; Figure 2 is a flowchart showing an alternative procedural embodiment of the present invention.

1(') The preferred embodiment to the present invention will now be described with reference to mobile telephones, although it is to be appreciated that the technology and security system to be herein described is not limited to such devices but may be utilised for all portable electronic equipment which have appropriate hardware 15 and/or software capable of identifying at least a relative location of the device and also a means for counting a pre-deterrnined event, whether such events are operational or time dependent.

Mobile phones, being lightweight and compact, are highly susceptible to theft. To 2() address this problem in the past, such phones were provided with security software allowing the authori.sed user to input a password code which would activate or deactivate the phone. Additionally, with the introduction of removable

SIM cards and the ability for a user to transfer the SIM card from one phone to

another phone (the SIM card identifying the user and their particular system requirements) appropriate security systems were developed to provide each SIM card with a unique PIN number (CHV L - Card Holder Verification 1 Number) which was embedded hi the card itself. Mobile phones, each time when powered 5 up, arc pre-programmcd to prompt the user to enter the correct PIN (CHV 1) number to be verified against the SIM card. The drawback of such a simple system, is firstly, the inconvenience to the authorised user who is repeatably required to enter their authorization code (and subsequently is enticed to disable such a security feature) and, secondly, since the required PIN number is simply to 1() provide authorised access to the SIM card, in stolen phones the SIM card is simply removed and replaced with a new, legally purchased SIM card with a new CHV1 PIN number.

Additional developments have attempter to address this problem by subsequently 15 introducing.software developments allowing the phones themselves to be selectively locked to appropriate SIM cards, whereby the user (or manufacturer) its able, upon insertion of the appropriate SIM card into an appropriate phone, to activate appropriate code recognition software within the phone so that the phone is only operable with that appropriate SIM card. Whilst this feature is of 9) considerable use as a deterrent to theft, it still requires that the primary operation of the CHVI recognition software remains active so as to continually require (on powering up) the authorised user to input the CHV1 PIN number to ensure that the phone has not been stolen. If the CHVI recognition feature is disabled and the

phone subsequently stolen, the phone remains operable with the original STM card. Therefore, in order to be used el'fectively, existing security systems still require the user to input an appropriate CHVI PIN number each time the mobile phone is powered up, which, as previously described, most end users are reluctant 5 lo do and thus the security system tends to be ignored (and de-activated) thereby undermining the benel'its of such a universal deterrent to thei't. Therefore, as with the majority of the existing security systems adopted by the mobile phone manufacturers, these systems all involve a high degree of interaction and password input by the end user who is reluctant to be inconvenienced by such I O systems.

The current invention overcomes the problem of existing systems for mobile communication devices by providing an automated security feature which is capable of partially or wholly disabling the mobile phone without the need for 15 interaction and continuous re-setting of the security system by the authorised user.

Mobile phones, by their very definition, are intended to be portable and carried by the user. However, it is also recognised that the user is able to define an appropriate "home location" be it a residential address, a work address or in tact 2() the location of the charger (such as in a car) . It is further recognised that all conventional mobile phones have appropriate location detection software which continuously monitor the relative location of that particular electronic device in relation to the communication network in order to efficiently detect the most

appropriate base station of the mobile communication network with which to interact upon usage of the mobile telephone.

In particular, mobile phones are often referred to as cellular phones due to the fact 5 that the mobile communication networks operate on a cell basis. Each service provider has developed a network of appropriate communication base stations and transmitters around their particular territory, dividing the territory into a number of areas serviced by each particular base station, which areas are referred to as "cells" (hence adoption of the term "cellular network"). The cells vary in size and 1() shape and arc dependent on the number of envisaged users within a particular area and the number of base stations and transmitters that are therefore allocated to a particular area. For example, a major city or town will have a high concentration of transmitters and base stations due to the high intensity of use of the mobile communication network, thereby creating relatively small cells as compared to IS rural areas whereby the users requiring operation of that mobile communication network are considerably reduced thus reducing the intensity of use on each base station. Authorised users of such mobile telephones often move from one cell to another 2() and, therefore, in order for the mobile phone to operate correctly and efficiently, it is important that the phone understands where it currently is in relation to the cells and thus periodically, and automatically, operates appropriate software to detect and communicate with the nearest base station and transmitter in order to identify

which particular cell the user is currently in. Thus, when the user wishes to operate the phone, the phone l;nows which transmitter it is trying to connect with.

Each particuhr cell its allocated an appropriate identification code recognized by the phone.

- Conventially, mobile phones are able to identify their location within one or more cellular networks by using one or more of the standard location identification systems which are able to determine and identify from the array of local transmitters one of a number of Cell Identification Codes (Cell Identity 1() Codes), in particular these include Cell Identity, Location Area Code, Mobile Comtry Code and Mobile Network Code. The exact electronic systems and software conventionally employed in mobile phones, and the method employed to determine these cell identification codes are well understood within the mobile phone hldr.stry and have standard features employed in all mobile phones. As 15 such, operation of such systems and use of these identification codes will not be described in detail herein but is considered to be common practice within the mobile phone industry readily incorporated into the current invention. The important feature here is that the phones are able to automatically determine their relative location within, one or more cell networks by reference to an identification 2() of one or more such codes. It is also important to note that operation of the current invention is not dependent on identification of a geographical location but is able to operate by determination of a location within a ceil network (ie. relative location).

Is The legitimate owner or user of such a mobile phone is thus able to readily identify an appropriate home location for their communication device during an initial set-up procedure (when the phone is first switched on or, upon accessing an 5 appropriate menu within the phone handset itself) whereby the user is simply able to request the phone to detect its location within the cellular network when at an appropriate location which he wishes to have designated as "home" location, using one of the location determination system of the type as described above, and to then allocate an appropriate code indicative ot the home location. If required, 1() the user will also be able, by selection of an appropriate menu driven system, to allocate any number of locations to be identified as acceptable home locations (when based at such additional locations). This will serve a dual purpose of allowing, for example, both residential home and a work home location to be set as home locations or, where a user may actually live in the region of cell IS boundary, then all cells party to that boundary could be entered as home location to adequately cover the appropriate geographical home location.

The current invention now provides for the phone to be simply programmed with an improved security system utilising standard mobile phone systems by use of 2() appropriate software implementation.

Primarily all modern electronic devices utilise an electronic clock to coordinate their electronic operation and, in its simplest form, the current invention provides

for the measuring or detection of a pre-determined number of events occurring when the phone location system detects the phone is remote from its home location. 5 Most mobile phones will undertake a periodic, automated, location detection operation (for example every ten seconds) and determine the cell in which it is currently located and a cell code (usually alphanumeric or electronic) allocated thereto. By a simple comparison, using appropriate software, against the preset code allocated to the home location, a simple comparator circuit or programme 1() will determine whether or not the phone is in its home location.

The simplest pre-determined event is considered to be the elapse of a known period ol time. In a preferred embodiment of the current invention the pre clctermined event will be established as the expiry of a period of one hour whereby 15 the counter may be preset to an initial value of eighteen, indicative of eighteen hours, whereby the system, on detection of the expiry of each one hour period subsequent to the phone initially detecting its removal from the home location, will effect the counter value being reduced by one. This is by way of example only and it will be appreciated that it will be only a minor amendment to set the 2() counter in minutes or even seconds with appropriate variations on the initial preset value of the counter and the pre-determined time event being reflected in minutes or seconds etc.

In the event that the counter then reaches a preset minimum value, usually set at zero, the system will recognise that the number of pre- determined events has equalled or exceeded the preset number that is considered acceptable for that particular mobile phone. Therefore, when the counter reads zero or a negative 5 value, an appropriate signal is generated by the counting system which will then selectively disable all or some functions of the mobile phone. Preferably, such security systems even when activated so as to disable the primary functions of the phone will still allow emergency calls to be made and calls to be received.

However, an exact mode of disablement of the mobile phone can be either pre 1 () programmed by the manufacturer or selectively chosen during a set-up phase by the phone owner by use of conventional menu driven options.

With reference to Figure 1 the current invention will now be described in more detail. Firstly, the security feature of the invention is activated by, for example, 15 switcilhg the phone on or entering an appropriate activation sequence through a menu driven option control or by unlocking the phone from a previously secured or locked configuration. An initial operation at step (1()) is carried out to reset the counter of the counting system as the preset value which, in this embodiment, will he eighteen representative of eighteen hours. Subsequently, the phone will be 2() programmed to undertake a location determination step (2()) by accessing the Cell Identity Code to determine the appropriate location code indicative of the determined location. At step (30), the phone will undertake a comparison of the determined location against the accepted home location codes to determine

whether or not the phone is in the or a home location. If home location is detected then the programme is returned to step (10) to reset the counter at 18, which el't'ectively maintains the counter at its maximum value and serves to effectively disable the security function. It'it is determined that the phone is not at its home 5 location it will then undertake to determine whether or not a specific pre detcrmined event has been detected which, in this situation, will be the elapse of a fixed period of time ( I hour). If in the event detection has not been detected then the system resets to step (20) and again determines the location. However, in the event that a pre-determined event has occurred at step (4()) then the counter is It) adjusted by the appropriate value at step (SO), which, in this case, will be the subtraction of the value of 1 from the counter value. A determination step (60) then determines whether or not the counter is less than or equal to zero. If the counter has not reached the zero value then the system resets to step (20) and again determines location. However, in the event that 18 pre-determined events 15 have been detected without determination of the home location then the counter will reach zero whereby the device will be disabled at step (70) by disabling all or certain l'unction.s ol' that mobile phone. Subsequent entry of the reset or cancel code will then return thc.system to the start to be reactivated.

?() In the event that the phone is still retained by the legitimate owner, the disablement can be selectively cancelled by the input of an appropriate cancel code through the keypad in a conventional manner. However, for the majority of occasions, a user would expect to return to the home location within an eighteen

hour period. In the event that they do so before the counter has reached the preset cut-otl value of zero and the phone subsequently determines that the device has returned to the home location, during a location determination step, then the counter may be returned to its initial value of eightec n and the security function 5 disabled whilst the phone is in and remains within the pre-determined home location. Thus whilst the phone remains in its home location the security feature is disabled and the user is free to use the device without fear of disablement and the need for re-entering a disarm code.

1() In its simplest fond, the countin, device will comprise a conventional electronic timer or clock for operating in a countdown mode.

Thins, the current invention provides for a mobile phone which, when removed Irom its home location, may be used with impunity for a certain period of time 15 before becoming disabled and necessitating the entry of a security code, W}liCh serves as a reset or cancel instruction to override the disablement. The basic principle adopted here, is that a legitimate owner will periodically return to the home location whereas if the phone is stolen it is highly unlikely to be returned to that home location, and certainly not on a regular basis. 2() Whilst the basic preferred embodiment described above outlines one

method of achieving the current invention, it will be appreciated that its implementation may be effected in numerous ways. In particular, instead of utilising a counting system

having a countdown function, the counter may initially be set at zero whereas the cut-off value may be set at a pre-determined number and the counting system opcratccl so that the counter increases by one on detection of each pre-clctcrmined evc',t. In either case, the exact number of pre-.selected events that may be 5 achieved before the device is selectively disabled can be pre-determined by either the manufacturer or by the user specific to their particular requirements.

In addition, whilst the preferred embodiment relies on the measurement of time that the device is away from the home location (as determination of an "event") 10 before disabling the mobile phone, any other means of measurement of use are equally applicable. For example, the pre-selected event may be the number of outgoing calls that may be made by the mobile phone, or it may be set as a number of incoming calls received by the mobile phone (a particular advantage that should the phone be stolen then the user may legitimately call their own 15 number for the known number of permitted events to disable it in a rapid manner).

Still further, it is also possible that the measurement of use be determined by the number ol minutes actually used for making outgoing calls (or alternatively incoming calls), thus the measurement of use would be independent of the number ot calls made but would simply restrict how long the phone could be used to make 2() or receive calls.

In a further enhancement, many modern mobile phones are further provided with means tor not only determining the period that a call is being made but is able to

identify the exact mode of that outgoing call and for specific times, tariffs and localion.s is able to calculate the cost value of such calls whereby the expenditure of a calculated value will equal the expiry of a pre-determined event. Thus the measure of use could be dependent on the value of calls being made on such a 5 mobile communication device. This has the enhanced benefit that, a thief is unable to Am up a very large bill on the phone before it is cancclled or the theft is even detected.

It is also possible that the measurement of the pre-detcrmined event could be the 1() number of times the phone is recharged or any other function which can be counted in some form or other. For example, the number of different cells located during movement of the phone, the number of times the mobile phone is switched on or oft, the number of times the keypad is activated. All such functions can be considered as a pre-determined event and can be counted, and thus can be used to 15 drive an appropriate counter of the counting system up to a preset maximum number of events whereby the security system is then implemented to partially disable the phone. The major benefit ot this invention is that current mobile phone technology and hardware already permit the detection and measurement of all of the "events" and the counting of such events is easily achieved by simple 2() software implementation, avoiding the additional cost of hardware modification.

A second example ot the current invention will now be described with reference to the flowchart shown in Figure 2. The programmed security feature is again

initiated in a similar manner to that described with reference to Figure 1, ea. by resetting the security feature, or, alternatively, by simply switching the phone on.

At.step (11()) the counter is reset to a pre-determined value which in this embodiment will be zero. Subsequently, at step (120) the device is programmed 5 to determine whether or not an event is being detected which, in this embodiment will be the making of an outgoing call from the mobile phone. If no event is detected the system simply loops back to step (12()) until such time that an event is detected. The mobile phone then is asked, at step (125) to determine its current location and is then able to retrieve that data from the standard location 1() determination system within the mobile phone. At step (130) the current location code is compared to the home location code or codes and, in the event that a home location is determined, the security system simply resets to step (110) and the counter is reset back to zero, effectively disabling the security system in the event that the phone determines it is still at or has returned to its home location.

15 However, if at step (130) it is detennined that the phone is remote from the home location the counter is suitably adjusted, at step (14()), by, in this particular example, increasing the counter value by l. At step ( 150) the programmed secfity system determines whether or not the counter has reached a pre determined maximum value of X (where X is representative of a number of 2() allocated calls that the phone can be used tor once the security system is activated). If the counter value has not reached X the system returns to step (120) to detect a further event. In the event at step (150) the counter is determined to have reached or exceeded the value of X then the device is again disabled by one

or more of the options previously discussed. This particular example utilises the detection ot a particular prc-determined event in order to determine the phone location, whereas the embodiment shown in Figure I continuou. sly monitored the phone location.

In a further enhancement of the present invention, it is also possible that the security system may be limited to being reset by input of the appropriate security (reset or cancel) code only when the device is at its home location. This would acidress the issue that should a thief physically threaten the user to reveal the reset l() code, then it is u nlikely that the thief would also be able to detect the known home location. As an additional innovative feature, the generation of the signal by the cou.,nting system when the counter reaches the preset value (used primarily to partially 15 disable the phone) can also be used to generate an appropriate warning or alarm signal. Such a signal is u.seci to activate an audible, visual or mechanical warning either simultaneously with disablement of the device, or prior to deactivation of the device such as to serve a warning to the user that it will be necessary to enter an appropriate cancel instruction imminently.

_ () Examples of such warnings would be the commencement of an audible alarm, or, for phones having vibrating alert, activation of the vibration alert system. Both the generation of a noise and vibratory alert would be unpleasant and conspicuous

and would further.scrve as a deterrent to a thief who is unable to deactivate such warnings. Such features would also he indicative of a potentially stolen device, thereby rendering such devices highly unattractive to thieves.

5 An example ol a visual warning signal that could be generated would be to completely blank out the display screen of the phone making its operation extremely difficult or, to simply place a written message on the display screen such as "Stolen Device".

10 One of the major benefits of this current invention is that it is readily implemented by simple software modifications to existing mobile telephones utilising the existing location determination systems and clock systems within the hardware already h.stalled in the device. It also provides the opportunity for the user to readily tailor the security system to their own needs whereby a light user can set 15 the measure of use facility to their particular needs as compared to a heavy user who continuously and frequently makes outgoing calls or uses the phone for long periods in any one day.

It is to be further appreciated that whilst most mobile communication devices, 2() automatically, pcriociically determine the device location, the system can be further modified such that initiation of the predetermined event (such as the making of an outgoing call) will automatically cause the mobile phone to undertake a location determination step to determine whether or not the security

system should be activated. This is applicable to any one of the predetermined events mentioned above.

Whilst the preferred embodiment has also been described with reference to a 5 mobile phone, the invention is equally applicable to all other forms of mobile electronic equipment which have the ability to access relative location information and an appropriate counting system, for example, a clock or timer. In particular, whilst this system can be implemented in a mobile telephone by the handset manufacturer alone, the system is equally applicable to implementation in the SIM 10 card or (other smarl-cards) with access to such time (or any other counting system) and location information. In particular, the application to a SIM card is of particular interest as detection of the expiry of the measurement of use could then be used to activate the CHV1 PIN code requesting that the user re-enters such PIN code otherwise rendering the SIM card useless to a thief. In particular, the 15 mechanism could be implemented in the SIM card instead of the phone by use of an appropriate SIM tool kit application using commands that have already been standardi.secl within the industry and are commonly available on SIMs.

Specifically, the location can be identified using the location status event and usage can be monitored by, for example, timer expiration or call connected event.

2() In this manner, whilst the SIM card itself is not capable of directly determining its location, it is able to do so by accessing the appropriate hardware of a mobile phone to determine its location. In implementation, using a SIM tool kit could operate in any phone that supports the required SAT commands whereby the SIM

application would be able to carry out all necessary interactions with the user via appropriate SAT commands. An additional benefit is that the appropriate reset code required by the user to enable the feature to be reset could be the default CHV1 PIN code, thus avoiding a proliferation of codes.

s Of course, when implemented he the SIM card, the system will protect the SIM card as opposed to the phone. However, it is feasible that both the phone and the SIM card could be protected ulilising the same mechanism and also by utilising the same reset code equivalent to the CHVI PIN code. Thus the term "electronic It) device" used in reference to the invention is intended to extend to cover SIM cards as wcil as mobile communication devices such as mobile telephones.

As is conventional for all types of security systems for electronic devices, the set-

up procedure should be readily accessible by the user so as to tailor the security 15 system to their particular requirements. It is therefore possible to use conventional methods of updating the necessary settings of the security system but only upon entry of the appropriate security reset code confirming that such information its being input by the authorised user.

2() Other envisaged usage of the current invention could be for all types of mobile electronic equipment which can detect location with reference to other equipment to which they are engageable with or operatively connectable to, and whose location is known. Such other equipment may be able to determine its location by

virtue of being in a fixed position (such as an ATM - Automatic Teller Machines), or because it incorporates a location detection system of its own (ea. CPS systems). In the case of fixed equipment, the identity of the equipment may be considered to effect location determination. In practice, the step of determining 5 location in order to determine whether the device is at the or an acceptable home location can be achieved by determining such information from other equipment from which the device is able to interact. For example, a conventional smartcard credit card is able to determine its location from engagement with an ATM machine which, if recognized as a ATM regularly used by the authorised card 1() owner, may be set as a home location, thereby allowing the card to be used. This procedure would then only allow limited number of uses of the card at ATM machines remote from such "home" ATM (without returning to such home ATM) before it its disabled.

15 Alternatively, an appropriate GPS system can be incorporated into such mobile electronic devices and utilised to determine location geographically by analysis of the appropriate signals issuing from the GPS satellites in a conventional manner.

This allows for home location to be determined within certain geographical perimeters detectable by use of such GPS technology.

9() Such a security system can be further expanded for use with all forms of smart cards. For example, modern financial payment or debit cards utilising smart-card technology have access to time and location information. Many modern payment

cards utilising smart-card technology interact with card readers which allow the smart-carcl to determine geographical location from information derived from the reader,.md can be readily programmed so as to limit the number of payments that can he made by such cards remote from a predetermined geographical region or 5 location or the duration that such card remains activated without determining a return to a home location, such that in the event that the smart-card is removed illegally from its authorised user and attempted for use elsewhere it will be quickly prohibited if that use is outside of the determined home location. Tn another example, the smart-card could be usable within a geographical home 1() location of the user in an appropriate reader for making electronic payments from such home reader but limited to the number oi payments that may be made from remote readers or the duration the card remains active if it is unable to determine a return to the home reader.

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Claims

C1 alms 1. A method of selectively disabling operation of a mobile

electronic device having a location determination system and a counting system, comprising 5 the steps of a) selectively identifying at least one preferred home location of said electronic device; b) determining current location of.said device; c) setting a counter of said counting system to a pre-determined initial JO value when said device determines said home location; d) activating said counting system when said location determination system identifies a location for said device different from said at least one preferred home location; e) varying said counter by a preset value in response to a pre-determined 15 event when counting system is activated; if at least partially disabling said device if said counter reaches or passes a preset cut-off value.
2. A method as claimed in claim I wherein said counter is reset to said pre 2() determined initial value when said device determines said home location.
a. A method as claimed in either of the preceding claims wherein said counting.system is deactivated when said device determines said home location. 5
4. A method as claimed in either of the preceding claims wherein said pre determined event is the expiry of a preset period of time.
5. A method as claimed in any one of the preceding claims wherein the location of the device is periodically determined automatically.

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6. A method as claimed in any one of the preceding claims wherein said location its determined in response to occurrence of said predetermined event. 15
7. A method as claimed in any one of the preceding claims wherein said location determination system determines location by the detection and analysis of signals from Global Positioning Satellites.
8. A method as claimed in any one ol the preceding claims wherein said 2() device is a mobile communication device.
9. A method as claimed in claim 8 wherein said pre-determined event comprises the making of an outgoing call on said communication device.
l (). A method as claimed in claim 8', wherein said pre-determined event comprises the expiry of a preset period of time derring which the communication device its being operated during either or both of the 5 making or receiving a call.
A method as claimed in claim 8 wherein said pre-determined event comprises the determination of a pre-deterrinined cost value associated with a particu..lar operation incl rred during the making, of a call.
12. A method as claimed in any one of claims to 1 l wherein said the location determination system uses mobile communications technology to determine at least one of Cell Identity, Location Area Code, Mobile Country Code Mobile Network Code or Network Measurement results to 15 identify the determined location.
13. A method as claimed in any one of the preceding claims wherein said pre determined initial value of said counter is set greater than zero and counter is varied by the subtraction of said preset value upon detection of a pre 2() detennhlecl event, whereby disabling of said device occurs when the counter reaches zero or a negative value.
14. A method as claimed in any one of the preceding claims wherein the step of disabling said device comprises electronically locking the operation of the device.

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15. A method as claimed in any one of the preceding claims wherein the step of disabling said device comprises mechanically preventing operation of the device.

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16. A method as claimed in claim 14 wherein the step of electronically locking the device is reversible by input of a preselected cancel instruction.
17. A method as claimed in claim 16 wherein said step of reversing said electronic locking of said device by input of cancel instruction is limited to 15 being dependent on determination of said home location.
18. A method as claimed in either claim 16 or claim 17 wherein input of said cancel instruction resets the counter to said pre-determined initial value.

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19. A method as claimed in any one of the preceding claims having a plurality of preferred home locations.
20. A method as claimed in any one of the preceding claims which is selectively deactivated by operation of a pre-selected disable instruction.
21. A method as claimed in claim 2() wherein operation of said preselected S disable instruction comprises input of a pre-determined electronic deactivation code.
22. A method as claimed in any one of the preceding claims wherein the step of at least partially disabling said device comprises disabling of pre 10 selected functions of said device.
23. A method as claimed in any one of the preceding claims further comprising generating an output signal upon said counter reaching said preset cut-off value.
24. A method as claimed in claim 23 wherein at least one of an audible, visual or mechanical warning is generated on determination of said output signal.
25. A mobile electronic device having a location determination system, a 20 counting system having a counter, a memory system for retaining a code indicative of at least one preferred home location for said device and a security mechanism for selectively disabling said device upon receipt of a pre-selected signals wherein said counter is automatically reset to a pre

En' determined initial value upon detection of location having a location code comparable to said code of said preferred home location, whereby said counting system is responsive to a pre-determined event so as to vary the value of said counter by a preset value as a result thereof when said 5 location determination system also determines a location different to said preferred home location, said counting system comprising means for generating said pre-selected signal upon variation of said counter to a preset cut-off value.

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26. A device as claimed in claim 25 wherein said location determination system will comprise at least one of a Cell Identity system, a Location Area Code identification system, a Mobile Country Code identification system, a Mobile Network Code identification system or a Network Measurement system to identify the determined location using mobile 15 communication technology.
27. A device as claimed in claim 25 or claim 26 further comprising a keypad and a security mechanism override circuit responsive to a predetermined code entered on said keypad to reset said security mechanism and reset 2() said counter.
28. A device as claimed in any one of claims 25 to 27 comprising a mobile communication device.
29. A method of selectively disabling operation of a mobile electronic device substantially as herein described with reference to the accompanying figures. s 3(). A mobile electronic device substantially as herein described with reference to the accompanying figures.

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