GB2381418A

GB2381418A - Multiple SIM mobile communications terminal

Info

Publication number: GB2381418A
Application number: GB0125921A
Authority: GB
Inventors: Tae Hyun Nam; Gaithri Maheswaranthan
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2001-10-29
Filing date: 2001-10-29
Publication date: 2003-04-30
Anticipated expiration: 2021-10-29
Also published as: GB0125921D0; GB2381418B

Abstract

A mobile communications terminal has two or more receiver circuits 130, 230 and is adapted to receive two or more SIMs (Subscriber Identity Modules) 102, 202 for simultaneously providing services or applications from different service providers or different subscriptions with the same service provider. The mobile terminal may also have more than one transmitter circuit. The terminal may share two receiver circuits between a greater number of subscriptions using an algorithm for assigning priorities to each subscription. The mobile terminal allows simultaneous use of call functions (voice or data), short message functions, registration functions (cell re-selection, PLMN selection, location updates) and supplementary service functions of different subscriptions.

Description

Multiple SIM Mobile Terminal This invention relates to mobile telecommunications terminals and methods of communicating via a mobile telecommunications network. More particularly, but not exclusively, the invention relates to a mobile communications terminal which is adapted to receive multiple SIM cards for simultaneously providing services from different service providers or simultaneously providing services from different subscriptions with the same service provider.

In a known conventional GSM (Global System for Mobile Communications) system, each mobile terminal, such as a mobile telephone handset, is provided with a SIM (Subscriber Identity Module), which is inserted into the mobile station in order to allow the mobile terminal to receive services in a GSM network from a particular service provider.

A typical SIM includes a microprocessor, memory elements and contacts for forming the data transfer interface between the SIM and the mobile terminal.

The SIM card stores information related to a particular subscription with a service provider. The SIM card is mostly removable from the mobile terminal and may be substituted by another SIM card for an alternative subscription. Thus different SIM cards may be used in one and the same terminal successively.

\lost mobile terminals can only receive a single SIM card in order to obtain the information relevant to a particular subscription. However, there are mobile terminals known in the art which simultaneously receive more than one SI ! \1 card or other subscriber identity module.

In patent application WO 99/45730 for example mobile phones are described which are designed to receive a plurality of different cards from different providers. If a user wants to place a call he may choose manually a particular provider who, for example. provides the best deal for a particular day, time or call destination. In addition. an automatic selection of the most convenient card may be chosen.

US patent 5. 764, 730 relates to a radiotelephone which provides for a plurality of subscriber identities. The radiotelephone network processes incoming and outgoing calls for the radiotelephone using any of the subscriber identities.

In US patent 5,764, 730 it is described that the plurality of subscriber identities may be registered simultaneously. When a call is transmitted or received using one subscriber identity. all other subscriber identities are deregistered while the call proceeds.

However, in the systems described above the abilities to handle simultaneously services from different subscriptions are significantly limited.

Conflicts might occur in a mobile terminal as described in the prior art when such a device simultaneously monitors paging channels from more than one service provider or from more than one subscription. The conflicts are

expected because the paging messages from different providers or different subscriptions might overlap in time.

If a mobile terminal is switched on and ready to receive services such as a call from a service provider, the subscriber needs to be registered in the cell of a location area in which the terminal is currently located. When the mobile station is moved into a place of another location area, the mobile station attempts to register the subscriber in a cell of that new location area by performing a location update procedure.

For this procedure the mobile terminal needs to transmit and receive messages to and from network nodes like the Mobile Switching Centre (MSC) and stores like the HLR and VLR of the serving network. A mobile terminal which is in the process of a call using a first service provider cannot perform a location update procedure with another service provider simultaneously.

Again, conflicts cannot be avoided in terminals according to the prior art because the two service providers may need to communicate with the mobile terminal at the same time.

It is thus an object of the present invention to alleviate the disadvantages described above and to provide a mobile station which is arranged to handle simultaneously services or applications from different subscriptions or different service providers.

According to one aspect of the present invention there is provided a mobile communications terminal comprising n receiver circuits and m transmitter circuits, said terminal being adapted to receive p subscriber

identifying means, wherein each subscriber identifying means provides access to services according to a particular subscription, and wherein n > : 2, m > : 1 and p > 2.

In this way multiple receiver circuits and multiple transmitter circuits are provided in a mobile terminal which may receive more than one subscriber identifying module, such that different communication applications may be carried out simultaneously for more than one subscription or more than one service provider.

Preferably, the number of receiver circuits is more than the number of transmitter circuits. This is advantageous for certain embodiments of the present invention, because certain applications such as idle mode services may only require receiver circuits. In this way these applications may be carried out simultaneously to other applications without the need of providing as many transmitter circuits as receiver circuits. A mobile terminal of such a design can be provided at a lower cost compared to a terminal with the same number of receiver and transmitter circuits. Also, the power consumption of such a terminal is lower than for a terminal with n receiver and n transmitter circuits.

In preferred embodiments of the present invention, the mobile terminal may receive more subscriber identifying means than it has receiver circuits. With such a mobile terminal idle mode applications may be handled simultaneously for all subscriptions for which subscriber identifying means may be received. Preferably, the terminal is further adapted to alert a user to

new or incoming applications. In this way the user may choose to terminate or put on hold an ongoing communications application when a new application comes in. In systems according to the prior art such incoming applications usually cannot be handled because there is no receive and/or transmitter circuit available.

According to another aspect of the present invention, there is provided a mobile terminal for communicating via a cellular telecommunications network adapted to receive more than one subscriber identifying means, each subscriber identifying means providing information to allow said mobile terminal to receive services according to a particular subscription, and said mobile further being adapted to handle simultaneously communications applications from different subscriptions.

Preferably, the terminal comprises n receiver circuits and m transmitter circuits, wherein n 2 and m > 1.

According to another aspect of the present invention, there is provided a method of communicating via a cellular telecommunications network, wherein n receiver circuits are shared in a single mobile terminal in order to provide services for at least n subscriptions from one or more service providers simultaneously.

By providing multiple receiver and/or transmitter circuits and by sharing receiver and/or transmitter circuits services may be handled simultaneously in an efficient way. In this way, for example, a mobile

terminal with n receiver circuits may handle more than n applications simultaneously.

According to yet another aspect of the present invention, there is provided a method of co-ordinating multiple receiver circuits and at least one transmitter circuit in a mobile terminal for simultaneously providing services according to multiple subscriptions with one or more service providers.

Further aspects and advantages of the invention will be appreciated from the following description and accompanying drawings, wherein: Figure 1 is a general schematic outline of a GSM mobile telecommunications network in which the present invention can be implemented; Figure 2 is a schematic illustration showing elements of a mobile terminal according to the prior art; Figures 3 to 5 are schematic illustrations showing elements of a mobile terminal with one transmitter circuit and two receiver circuits, two transmitter circuits and two receiver circuits. and two transmitter circuits and three receiver circuits, respectively, according to different embodiments of the present invention; Figures 6 and 7 are schematic diagrams showing communications terminating and originating at the receiver and transmitter circuits of a mobile terminal according to two different embodiments of the present invention;

Figures 8 A and B are flowchart diagrams illustrating the procedure of determining whether receiver circuits are available according to two embodiments of the present invention; Figure 9 is a flowchart diagram illustrating sequence idle mode procedures according to aspects of the present invention; Figures 10 A and B are parts of a flowchart diagram and Figure 11 is a further flowchart diagram illustrating sequence dedicated mode procedure according to aspects of the present invention; and Figure 12 is a flowchart diagram illustrating the overall control over a mobile terminal according to one embodiment of the present invention.

In Figure 1 a schematic outline of a mobile telecommunications network according to the GSM standard is shown. A Mobile Switching Centre (MSC) is connected via communication links to a number of Base Station Controllers (BSCs) 4. The BSCs are dispersed geographically across areas served by the Mobile Switching Centre 2. Each BSC 4 controls one or more Base Transceiver Stations (BTSs) 6 located remote from, and connected by further communication links to, the BSC 4. Each BTS 6 transmits radio signals to, and receives signals from, mobile stations 8 which are in an area served by that BTS 6. The area is referred to as a"cell". A GSM network is provided with a large number of such cells. which are ideally contiguous to provide continuous coverage over the whole network territory.

The mobile switching centre is provided with a Home Location Register (HLR) 12 which is database storing subscriber data. The mobile

Switching Centre 2 is also provided with a Visitor Location Register (VLR) 14 which is a database temporarily storing subscriber data for mobile stations which are active in the area served by the Mobile Switching Centre 2.

In Figure 2 a schematic diagram of a mobile telephone handset 100 according to the prior art is shown. A SIM 102 is connected to the handset.

Communications with the SIM 102 and input via the user interface 104 are controlled 0 : microcontroller 106. The microcontroller further controls the transmission and reception of the radio signals via transceiver circuit 128 and receiver circuit 130. Other elements of the handset include a GMSK (Gaussian Minimum Shift Keying) modulator 118 and demodulator 124, a channel coder 120 and decoder 122 and a baseband filter 126.

Microcontroller 106 is connected to a transmitter power control digital to analog converter (DAC) (114). a receiver automatic gain controller (AGC) DAC (116) and an automatic frequency correction (AFC) DAC (108). The timing is controlled by a reference clock (110) and a timing block (112).

In mobile stations known in the an which are adapted to receive simultaneously two or more SIM cards, the other SIM card (s) are also connected to the microcontroller. However, the elements related to the transmission and reception of radio signals (108 to 130) are not modified.

In Figure 3 a mobile terminal is shown according to one embodiment of the present invention. Here, a second SIM 202 is provided in addition to a first SIM 102. In this case all SIMs are connected to and controlled by the microcontroller 106. Elements which correspond to the elements as described

with reference to Figure 2 are depicted by the same reference numerals. The terminal comprises one transmitter circuit 128 and two receiver circuits 130 and 230. Furthermore, all elements directly related to the receiver circuits are provided twice. For example, a second channel decoder 222, GMSK demodulator 224, baseband filter 226 and elements 208 to 212 and 216 are provided. In addition a multiplexer 240 is connected to the two receiver circuits 130 and 230 and transmitter circuit 128. In this way the terminal may share the two receiver circuits for different applications. Alternatively, a plurality of p SIMs may be provided.

In Figure 4 a further embodiment of the present invention is shown.

Here a mobile terminal with two transmitter circuits 128 and 228 and two receiver circuits 130 and 230 is shown. Similarly to the embodiment shown in Figure 3, here all elements related to the receiver circuit (108 to 112,116, 122 to 126,208 to 212,216 and 222 to 226) and all elements related to the transmitter circuit (114,118, 120,214, 218 and 220) are provided twice. The two receiver circuits 130,120 and the two transmitter circuits 128,228 are connected to multiplexer 240. The mobile station described above is able to receive p different SIM cards, as is depicted in Figure 4 and is further able to share the two receivers and two transmitter circuits between different applications of the p subscriptions.

In Figure 5 yet another embodiment of the present invention is shown.

Here two transmitter circuits (128 and 228) and three receiver circuits (130, 230 and 330) are provided. All receiver and transmitter circuits are connected

to multiplexer 240. Again, the terminal is adapted to receive p different SIM cards, and the microcontroller 106 controls the distribution of the receiver and transmitter circuits to the applications of the p subscriptions.

In the embodiment described with reference to Figures 3 to 5 the relevant element related to the receiver and transmitter circuits are duplicated. Alternatively, multiple receiver and/or transmitter circuits are implemented in other ways, for example such that the circuits share at least some individual components.

A mobile terminal with p SIM cards may either allow subscription with p different service providers, p different subscriptions with one and the same service provider or a combination of the previous two options.

When a GSM mobile station is powered on, it may either be in a socalled idle mode, where the station listens to broadcast channels, but has no channel of its own. or in dedicated mode. where a bi-directional channel is allocated to the mobile station for communication with the network.

In the idle mode the mobile station continuously monitors the paging channel (PCH) of the serving cell of a particular service provider in order to intercept paging messages, for example if its user is being called, or short messages sent to the terminal. In order to handle multiple subscriptions of different service providers simultaneously, a terminal has to be able to monitor the paging channels of the different serving cells associated with the respective service providers. It may happen that the paging signals of the different cells overlap in time. In order to avoid such potential conflicts a

mobile terminal according to embodiments of the present invention is provided with at least two receiver circuits.

A GSM mobile terminal usually performs measurements relating to other, neighbouring, cells of the same service provider in between monitoring the serving cell. It is therefore advantageous to provide more than one receiver in a mobile terminal handling multiple subscriptions in order to cope with possible conflicts in monitoring different serving cells and to allow sufficient neighbour cell measurements.

A mobile provided with one transmitter circuit and more than one receiver circuits may for example monitor paging channels of different serving cells and simultaneously accept an incoming call. With reference to Figure 6, an example is given of how a mobile terminal according to one embodiment of the present invention is able to alert a user that a paging message is coming in from a first subscription X of a first network PLMN X while the user is in a call via a second network PLMN Y using a second subscription Y. It is noted that PLMN X may also be the same network as PLMN Y.

In step 401 the transmitter sends uplink (UL) voice signals via the traffic channel (TCH) to the serving base station of the second network PLMN Y. In step 402 the first receiver receives down link (DL) voice signals from the serving base station, again via the TCH.

When the first receiver (Receiver 1) is not occupied by the reception of voice signals according to step 402, Receiver 1 may perform neighbour cell

measurements and receive signals from different neighbour cells of the network PLMN Y via a common control channel (CCCH), as is indicated in step 403.

Simultaneously to the ongoing call (steps 401 and 402), the terminal may receive (step 404) a paging message from the serving base station of the network PLMN X via the CCCH at the second receiver (Receiver 2). The mobile terminal may then alen the user of the incoming paging signal (step 405).

The user can then decide if he wants to clear the current call in order to accept the incoming call or communication from network PLMN X or if he prefers to continue with the ongoing call using network PLMN Y. The call may be for example a voice or a data call. or alternatively a short message may be received.

However, while the user is in an ongoing communication using a first subscription, he cannot discover the reason for an incoming paging (i. e. whether it is due to a data call. voice call or SMS message) unless he clears the ongoing call. \\'hen the second receiver is not occupied, Receiver 2 may perform neighbour cell measurements and receive signals from different neighbour cells of the network PLMN X via a CCCH in step 406.

The same functionalities or communication applications as described above are of course possible with a terminal providing n receiver circuits and one transmitter circuit. A terminal with n receiver circuits and one transmitter circuit is also able to handle other applications simultaneously. Such a mobile

terminal may for example clear an ongoing call and accept a new call using another subscription. However, only one call may be accepted simultaneously, the other subsequent pagings being ignored. Also other applications such as dedicated mode procedures (e. g. registration or routing area updates) may be delayed until a receiver and transmitter circuit become available when the call is finished.

A terminal with n receiver circuits may receive more than n SIM cards for more than n different subscriptions. However, a terminal with n receiver circuits can only handle p subscriptions (for p > n) simultaneously if a procedure is defined to assign receiver circuits to the communications applications if more than n receiver circuits are required.

In a preferred embodiment of the present invention a technique for sharing n receivers between p subscriptions is based on the assignment of priorities. The receiver circuits are then assigned to the different communication applications of the p subscriptions according to the given priorities.

The degree of service availability for the active subscriptions will also depend on the choice of the algorithm for assigning receiver circuits if applications compete for the receiver circuits. Thus it is important to provide an efficient procedure to assign receiver and transmitter circuits. One possibility is to assign receiver circuits according to a priority algorithm.

Figure 8A is a flowchart diagram showing the procedure of determining whether a receiver circuit is available for a particular

communications application using a priority algorithm for assigning receiver circuits.

In step 602 a receiver circuit is required for an application X. Thus it is enquired in step 603 if there is an unused receiver circuit available. If the answer is yes. then an indication is given X in step 604 that the receiver circuit can be used for an application and the procedure ends in step 612. If there is no unused receiver circuit available, it is asked for the priority x of application X in step 605. It is now enquired whether there is a receiver circuit in use for an idle mode procedure having a priority smaller than the priority x of application X in step 606. If yes, then the receiver circuit used for this process with lower priority is released (step 609) and subsequently available for application X. An indication is given in step 610. However, if no such receiver circuit with a priority less than x is available, there is no receiver circuit available for application X. An indication is given and the procedure is ended (steps 607 and 608).

An alternative to the use of priorities is to use the effectiveness of each idle mode process as the criterion for assigning receiver circuits. Effectiveness could be a measure of the rate of cell power measurements, reading of system information and reading of paging messages. The idle mode process that is least effective is the one that would give up its use of a receiver circuit when a circuit is be allocated. The effectiveness could for example be monitored continuously.

Such a procedure is illustrated in Figure 8B. Steps 601 to 604 are the same as in Figure 8A. However, after step 603 it is enquired in step 613 whether there are any receiver circuits being used in idle mode procedures. If the answer is affirmative, then the receiver circuit used in an idle mode procedure with the lowest effectiveness is released in step 614. If the effectiveness of all procedures is equal, then a receiver circuit may for example be chosen at random. The procedure then continues in step 610 by indicating that a receiver circuit is available. If no receiver circuit is used in an idle mode procedure, then the procedure continues in step 607 by indicating that no receiver circuit is available.

According to embodiments of the present invention, it is possible for a terminal with n receiver circuits to provide simultaneous idle mode service for more than n subscriptions.

An example procedure of assigning receiver circuits to idle mode procedures when n receiver circuits are shared for more than n subscriptions is illustrated in the flowchart diagram of Figure 9.

In step 702 an idle mode procedure has to be carried out and thus a receiver circuit is required (703). If no receiver circuit is available, the idle mode procedure cannot be carried out (step 705) and the procedure continues with step 701. The procedure may for example be delayed until a receiver circuit becomes available. If a receiver circuit is available, it can be used to receive signals over the required channel (step 706). The idle mode procedure is carried out (step 707) and the results are made available in step 708.

Subsequently the receiver circuit is released (step 709) and is available for other applications.

With a mobile terminal providing at least two receiver circuits but only one transmitter circuit, as described above, the user may for example choose to clear the ongoing call (steps 401 and 402) before accepting the second call of which he was alerted in step 405. However, the mobile terminal cannot perform two functions or communications applications simultaneously which both need a transmitter circuit. For example, the mobile station cannot accept two calls.

In a second embodiment. as described with reference to Figure 4, a mobile terminal is provided with two receiver circuits and two transmitter circuits. In addition to the communications application described above, a mobile terminal may for example be used to explicitly reject a second call while in an existing call or to clear one of two simultaneous calls.

More generally. such a mobile terminal provides for simultaneous use of dedicated mode procedures for two (or more) different subscriptions. Such dedicated mode procedures may for example include call functions (voice or data), short message functions, registration functions and supplementary service functions. Registration functions may, for example, include procedures like cell re-selection, manual or automatic PLMN selection or periodic location updates.

With reference to Figure 7, an example is now given of how a terminal according to embodiments of the present invention may simultaneously

handle dedicated mode functions, i. e. how the terminal registers subscription X with network PLMN X whilst in an ongoing call using subscription Y and network PLMN Y. Steps 501 to 503 are analogous to steps 401 to 403 of Figure 6.

Simultaneously to the ongoing call via network PLMN Y (steps 501 and 502), the terminal registers a second subscription X with network PLMN X in steps 504 and 505. The second transmitter circuit (Transmitter 2) sends uplink registration messages (step 504) via a dedicated control channel (DCCH) to the serving base station of network PLMN X. The second receiver circuit (Receiver 2) receives downlink registration messages from the serving base station in sep 505, again via a DCCH. When the second receiver is not occupied by the reception of the downlink messages according to step 505, Receiver 2 may perform neighbour cell measurements and receive signals from CCCHs in step 506.

A terminal according to the described embodiments of the present invention automatically pairs the transmitter circuit with the appropriate receiver circuits.

The simultaneous provision of other dedicated mode procedures works according to the same principles.

Figures 10 and 11 are flowchart diagrams illustrating examples of dedicated mode procedures carried out by mobile terminals according to the present invention.

With reference to Figures 10 A and B an example is given how a mobile station with more than one receiver and transmitter circuits may handle an incoming paging message for a particular subscription.

After the paging message for an incoming communications application has been received (step 802), it is enquired in step 803 whether a transmitter circuit is currently available. If the answer is negative, the user is alerted to the incoming paging message in step 807. The user may then decide whether he wants to clear the (or one of the) ongoing call (s) in order to make a transmitter circuit available for the incoming application (step 808).

If no call (or alternatively another application requiring a transmitter circuit) is cleared. then the dedicated mode procedure cannot be carried out and the incoming paging message is not answered (step 809).

If an application is cleared in step 808. then a response is given to the paging in step 806. However, if on the other hand a transmitter is found to be directly available in step 803, it is noted in step 804 that a receiver circuit is required. It is now checked in step 805 whether a receiver circuit is available.

If not. again the user is alerted in step 807 and it is continued with step 808.

If a receiver circuit is available, the incoming paging message is again answered in step 806. If no receiver circuit is available in step 805, the process is continued in step 807, alerting the user to the paging. It is now checked in step 810 whether the call requires user interaction. If the answer is negative, a sequence call accept procedure is carried out in step 814. If user interaction is required. the user is alerted to the call in step 811. If the user

accepts the call in step 812, the sequence call accept procedure can now be carried out (step 814). If, on the other hand, the user does not accept the call, a sequence call reject procedure is carried out in step 813 and the procedure is ended (step 819).

After the call accept procedure has been carried out in step 814, the mobile station handles the ongoing call in the usual way (step 815). After the call is finished (step 816), the call is cleared in step 817 by a sequence call clearing procedure and the transmitter and receiver circuits are released (step 818). They are now available for further applications.

Figure 11 illustrates how a call request or telephone application is handled from a mobile terminal with more than one transmitter and receiver circuits. After the call request or a request for a phone application has been received from the user in step 902, the steps of checking whether transmitter and receiver circuits are available (steps 903 and 905) are equivalent to steps 803 to 805 of Figure 10.

If no transmitter and/or receiver circuit is available, the call request is rejected in step 909 and the user informed in step 910. If both circuits are available, a sequence call set-up is performed in step 906. If the call set-up is successful (step 907), the user is then in a call using a particular subscription.

If the call set-up is not successful, the user is informed in step 910.

With reference to Figure 12 now an example of the overall call control of a mobile terminal according to the present invention is described. After the mobile station is switched on in step 1002, the subscriber information from all

inserted SIM cards is read in step 1003. It is checked in step 1004 whether all subscriptions are activated.

If the answer is negative, a number of idle mode procedures are created for a first non-activated subscription in step 1005. First a cell power measurement procedure is created, another idle mode procedure is created for reading system information messages and subsequently a process is created

for monitoring paging messages according to the first subscription.

9 Subsequently a dedicated mode procedure is created (step 1006) for the first subscription. It is then checked again in step 1004 if all subscriptions are activated. If not. steps 1005 and 1006 are repeated with a second and any further non-activated subscription until all subscriptions are activated.

Subsequently, the subscriptions and the different applications of the subscriptions are prioritised in step 1007 if a priority algorithm is used for assigning receiver circuits. The subscriptions and applications may for example be automatically prioritised according to a predetermined order.

Alternatively, or additionally, the user may manually set the priorities for one or more particular subscriptions/applications. If other methods are used to assign the receiver (or transmitter) circuits, then other processes may be activated in step 1007. such as a process for monitoring the effectiveness of the idle mode procedures in case that an effectiveness criterion is used.

In step 1008 a process is created to determine if a receiver circuit is available, such as the process explained with reference to Figure 8 above. In step 1009 the mobile terminal is activated. If the mobile station is now

powered down (step 1010), all ongoing calls or communication applications and all subscription registrations with service providers are cleared (steps 1011 and 1012).

Generally, the number of transmitter circuits in a mobile terminal does not need to be the same as the number of receiver circuits. For many applications it is advantageous to provide more receiver circuits as transmitter circuits because some applications such as for example idle mode procedures require solely receiver circuits and no transmitter circuits. In such configurations the mobile terminal may for example be able to perform neighbour cell measurements or to receive paging messages with additional receiver circuits simultaneously with ongoing dedicated mode procedures which require both receiver and transmitter circuits.

As mentioned above, the number of subscriptions for which there is idle mode service available may be greater than the number of receiver circuits. The number of subscriptions for which there is service available is generally determined by the number of receiver circuits, the cell configuration and the relationship in time between cells of different subscription, the services offered by the service providers and the proportion of subscriptions for which dedicated mode services are ongoing.

The number of subscriptions which are simultaneously in dedicated mode service is usually limited by the number of transmitter circuits in the mobile terminals. For many applications the transmitter circuits cannot be multiplexed between channels for different subscriptions, because the mobile

station does not have influence on the timing of many dedicated mode services, and thus an overlap between different dedicated mode channels of different subscriptions cannot necessarily be avoided.

However. for certain applications or in certain circumstances, the multiplexing of transmitter circuits might be possible, and in these instances more applications mas be provided simultaneously than there are transmitter circuits provided in a mobile terminal.

A mobile terminal according to embodiments of the present invention may indicate subscriptions for which there is currently service provided.

The SIM Toolkit or SIM Application Toolkit extends the role of the SIM card and allows the SINI card to be programmed to carry out new functions. The SIM card may for example access the network or control access to the network. Thus the SIM Toolkit function may also require dedicated mode sen ices. The SIM Toolkit function is directly associated with the SIM of a particular subscription.

If the SIM Toolkit application requires dedicated mode services, the coordination of the receiver and transmitter circuits is handled in the same way as for a mobile originated SMS call. If the SIM Toolkit function is initiated from the network side. then the receiver and transmitter circuits are coordinated in the same way as for a SMS message terminating in the mobile terminal. However. if the SINI Toolkit application is initiated by the user, then the user may indicate which subscription the SIM Toolkit application shall use.

Whilst in the above described embodiments a communications network and mobile stations according to the GSM standard are described, it is appreciated that the invention may alternatively be implemented into networks of any other standard, including any third generation standard.

Moreover, the invention may also be implemented into multi-standard mobile terminals, such that receiver and transmitter circuits are co-ordinated for networks of compatible technology. GSM 900, DCS 1800, PCS 1900, GPRS and EDGE are all suitable, as for these modes the lower layer technology for the receiver and transmitter channels are compatible.

The invention may also be applied to multiple subscription CDMA mobile terminals, i. e. where all subscriptions are according to the CDMA standard.

Whilst in the above described embodiments a SIM is described, it is appreciated that subscriber identifying means or information storage means other than a SIM card may be used.

Whilst in the above described embodiments a priority algorithm or a effectiveness criterion is used to assign receiver or transmitter circuits to communication applications and/or idle mode procedures if more circuits are required at the same time than are available, it is appreciated that alternatively other procedures may be used which assign receiver and transmitter circuits to communication applications and/or idle mode procedures.

It is to be understood that the embodiments described above are preferred embodiments only. Namely, various features may be omitted,

modified or substituted by equivalents without departing form the scope of the present invention. which is defined in the accompanying claims.

Claims

CLAIMS:

1. A mobile communications terminal comprising n receiver circuits and m transmitter circuits, said terminal being adapted to receive p subscriber identifying means, wherein each subscriber identifying means provides access to services according to a particular subscription, and wherein n 2, m 1 and p > 2.

2. A mobile terminal according to claim 1, wherein n m.

3. A mobile terminal according to claim 1 or 2, wherein n > m.

4. A mobile terminal according to claim 1,2, or 3, wherein p > n.

5. A mobile terminal according to any of claims 1 to 4, wherein said terminal is adapted to handle idle mode applications for p different subscriptions simultaneously.

6. A mobile terminal according to any of claims 1 to 5, wherein said terminal is adapted to simultaneously handle a communications application for a first subscription and at least one idle mode application for a second subscription.

7. A mobile terminal according to any of claims 5 or 6, wherein said idle mode application comprises any of the following applications: reading of system information, cell power measurements, monitoring of paging channels and synchronisation to cells.

8. A mobile terminal according to claim 5,6 or 7, wherein said terminal is further adapted to alert a user to potential communications applications.

9. A mobile terminal according to any preceding claim, wherein

m2.

10. A mobile terminal according to claim 9, wherein said terminal is adapted to perform simultaneously communications applications for up to m different subscriptions.

11. A mobile terminal for communicating via a cellular telecommunications network adapted to receive more than one subscriber identifying means, each subscriber identifying means providing information to allow said mobile terminal to receive services according to a particular subscription and said mobile terminal further being adapted to handle simultaneously communications applications from different subcriptions.

12. A mobile terminal according to claim 11, said terminal comprising n receiver circuits and m transmitter circuits, wherein n > 2 and m > 1.

13. A mobile terminal according to claim 6,10, 11 or 12, wherein said communications application comprises any of the following applications: voice call, data call, registration, location update procedure, SIM Toolkit applications, short messages and supplementary service functions.

14. A method of communicating via a cellular telecommunications network, wherein n receiver circuits are shared in a single mobile terminal in order to provide services for at least n subscriptions from one or more service providers simultaneously.

15. A method according to claim 14, wherein a priority is assigned to any of said services and if more than n receiver circuits are required said receiver circuits are conferred according to said priorities.

16. A method according to claim 14 or 15, wherein m transmitters are shared in said mobile terminal in order to provide simultaneously services for said at least n subscription.

17. A method according to claim 14,15 or 16, wherein a priority is assigned to any of said services and if more than n receiver circuits are required said transmitter circuits are conferred according to said priorities.

18. A method according to claim 16 or 17, wherein up to m communications applications are handled simultaneously.

19. A method of co-ordinating multiple receiver circuits and at least one transmitter circuit in a mobile terminal for simultaneously providing services according to multiple subscriptions with one or more service providers.

20. A method according to claim 19, wherein multiple transmitter circuits are co-ordinated.