Terminal device and method for switching modules of the terminal device

Abstract

This technology enables communication between terminal devices even when outgoing call restrictions are in place. [Solution] The terminal device includes a communication unit that receives notification information from a base station, and a switching unit that identifies an access class subject to transmission restriction from the notification information, and if a first module unit that records the same access class as the identified access class is being used, it performs a switching process to a second module unit that records an access class with a different value from the identified access class from among a plurality of module units.

Description

Technical Field

[0001] The present disclosure relates to a terminal device and a module switching method for a terminal device.

Background Art

[0002] Generally, an LTE (Long Term Evolution) system is composed of at least an EPC (Evolved Packet Core) which is a core network, an eNB (evolved Node B) which is a base station, and a communication terminal such as a smartphone.

[0003] The eNB is connected to the EPC that manages the eNB on a national scale via an S1 interface. The communication terminal connects to the eNB to perform communication. Also, communication terminals with different connected eNBs communicate via the EPC.

[0004] In a PS (Public Safety)-LTE system, a local core network device (local EPC) responsible for a small-scale area compared to the EPC is installed in the same premises as the eNB. The eNB is preset to make S1 connections to a plurality of EPCs (including the local EPC).

[0005] Also, in the LTE system, a function (call restriction) for restricting the outgoing calls of communication terminals such as smartphones is used. The call restriction is performed using the notification information transmitted by the eNB and the AC (Access Class) recorded in the USIM (Universal Subscriber Identity Module) of the communication terminal.

[0006] Patent Document 1 below describes that a second terminal, having received call restriction information from both the first and second eNBs, is unable to make calls to the second eNB but can make calls to the first eNB, and therefore connects to the first eNB. Similarly, a first terminal, having received call restriction information from the first eNB, is also able to make calls to the first eNB and therefore connects to the first eNB. This enables communication between the first and second terminals via the first eNB and the local EPC. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] International release 2023 / 105572 [Overview of the project] [Problems that the invention aims to solve]

[0008] For example, if the backhaul connection between the EPC and the eNB is interrupted, outgoing traffic restrictions are imposed at the eNB. In the event of a disaster or other incident that causes a backhaul interruption, it is desirable to use access classes to control the connection to another common eNB. However, communication terminals located outside the service area of ​​another eNB will be unable to communicate with communication terminals located within the service area of ​​that eNB. This problem cannot be solved even by using the invention disclosed in Patent Document 1.

[0009] This disclosure has been made in view of the above-mentioned issues, and one exemplary purpose thereof is to provide a technology that enables communication between communication terminals even when outgoing transmission restrictions are in place. [Means for solving the problem]

[0010] Each terminal device relating to an exemplary aspect of this disclosure comprises a plurality of module means recording different access class values, a communication means for receiving broadcast information from a base station, and a switching means for identifying an access class subject to transmission restriction from the broadcast information, and, if a first module means recording the same access class as the identified access class is being used, executing a switching process to a second module means from the plurality of module means recording an access class with a different value from the identified access class, wherein the communication means uses the second module means to connect to the base station and communicate with other terminal devices.

[0011] A module switching method for a terminal device relating to an illustrative aspect of this disclosure includes: receiving broadcast information from a base station; identifying an access class subject to transmission restrictions from the broadcast information;, if a first module is being used that has the same access class value as the identified access class recorded, performing a switching process from among a plurality of modules to a second module that has an access class value different from the identified access class recorded; and using the second module, connecting to the base station and communicating with other terminal devices. [Effects of the Invention]

[0012] According to the illustrative aspects of this disclosure, one exemplary effect is that communication can be carried out between communication terminals even when outgoing transmission restrictions are imposed. [Brief explanation of the drawing]

[0013] [Figure 1] This is a block diagram showing an example configuration of a terminal device related to this disclosure. [Figure 2] This is a flowchart illustrating the processing procedure of the terminal device related to this disclosure. [Figure 3] This is a block diagram showing an example configuration of a terminal device related to this disclosure. [Figure 4] This is a block diagram showing an example configuration of a wireless communication system including a terminal device related to this disclosure. [Figure 5] This diagram schematically illustrates the processing of terminal equipment when a backhaul disconnection occurs between the EPC and the eNB. [Figure 6] This is a flowchart illustrating the processing procedure of the terminal device related to this disclosure. [Figure 7] This is a diagram showing an example of computer hardware. [Modes for carrying out the invention]

[0014] The following are examples of embodiments of the present invention. However, the present invention is not limited to the exemplary embodiments shown below, and various modifications are possible within the scope of the claims. For example, embodiments obtained by appropriately combining the technical means employed in each of the exemplary embodiments shown below may also be included in the scope of the present invention. Furthermore, embodiments obtained by appropriately omitting some of the technical means employed in each of the exemplary embodiments shown below may also be included in the scope of the present invention. In addition, the effects mentioned in each of the exemplary embodiments shown below are examples of effects that can be expected in that exemplary embodiment and do not define the scope of the present invention. That is, embodiments that do not produce the effects mentioned in each of the exemplary embodiments shown below may also be included in the scope of the present invention.

[0015] [First Exemplary Embodiment] A first exemplary embodiment, which is an example of an embodiment of the present invention, will be described in detail with reference to the drawings. This exemplary embodiment is the basic form for each of the exemplary embodiments described later. The scope of application of each technical means adopted in this exemplary embodiment is not limited to this exemplary embodiment. That is, each technical means adopted in this exemplary embodiment can also be adopted in other exemplary embodiments included in this disclosure, to the extent that no particular technical problems occur. Furthermore, each technical means shown in the drawings referenced to explain this exemplary embodiment can also be adopted in other exemplary embodiments included in this disclosure, to the extent that no particular technical problems occur.

[0016] (Configuration of Terminal Device 1) The configuration of terminal device 1 will be described with reference to FIG. 1. FIG. 1 is a block diagram showing a configuration example of terminal device 1. Terminal device 1 includes a first module unit 11, a second module unit 12, a communication unit 13, and a switching unit 14. Hereinafter, the case where terminal device 1 performs wireless communication in the LTE system will be described, but it can also be applied to the case where terminal device 1 performs wireless communication in 5G (the fifth-generation mobile communication system) or the like.

[0017] The first module unit 11 and the second module unit 12 each record access classes with different values. The first module unit 11 and the second module unit 12 may be, for example, USIM cards mounted in terminal device 1, or software having functions equivalent to those of the USIM cards mounted in terminal device 1. Hereinafter, the first module unit 11 and the second module unit 12 may also be referred to as USIMs.

[0018] In the LTE system, the base station stores in each cell it operates in the form of a master information block (MIB (Master Information Block)) and a plurality of system information blocks (SIB (System Information Block)), and broadcasts them periodically as notification information. Among the SIBs, SIB2 particularly includes radio resource configuration information, prohibition information, and radio resource configuration of common channels.

[0019] The access class is one of the information included in SIB2 and is information for designating a terminal device that performs call restriction. For example, if the bit string of AC-BarringInfo notified by the base station in the notification information (SIB2) is "10000", the terminal device of AC11 will be subject to call restriction.

[0020] For example, if the access class recorded in the first module unit 11 is "AC11", and the access class subject to call restriction notified by the base station is "AC11", then the terminal device 1 will be subject to call restriction if it is using the first module unit 11.

[0021] The communication unit 13 receives broadcast information from the base station. The communication unit 13 is the part that performs wireless communication with base stations such as eNB in ​​an LTE system and gNB (next generation NodeB) in 5G.

[0022] The switching unit 14 identifies the access class subject to transmission restriction from the broadcast information, and if it is using the first module unit 11 which has the same access class value as the identified access class recorded, it performs a switching process to the second module unit 12 which has an access class with a different value from the identified access class recorded from among the multiple module units.

[0023] For example, suppose the first module unit 11 has access class "AC11" recorded, and the second module unit 12 has access class "AC12" recorded. If the access class subject to the transmission restriction notified by the broadcast information is "AC11", the switching unit 14 executes a switching process from the first module unit 11, which has access class "AC11", to the second module unit 12, which has access class "AC12".

[0024] The communication unit 13 then uses the second module unit 12 to connect to the base station and communicate with other terminal devices.

[0025] (Effect of terminal device 1) As described above, in terminal device 1, if the switching unit 14 is using the first module unit 11 which has the same access class value as the identified access class recorded, it performs a switching process from among the multiple module units to the second module unit 12 which has an access class value different from the identified access class recorded. Therefore, even if outgoing call restrictions are in place, communication can be performed between terminal devices.

[0026] (The flow of the module switching method) The flow of the module switching method S1 for terminal device 1 will be explained with reference to Figure 2. Figure 2 is a flowchart showing the flow of the module switching method S1. As shown in Figure 2, the module switching method S1 includes processes S11 to S14.

[0027] First, the communication unit 13 receives broadcast information from the base station (S11). The communication unit 13 is the part that performs wireless communication with base stations such as eNB in ​​an LTE system or gNB in ​​5G.

[0028] Next, the switching unit 14 identifies the access class subject to transmission restriction from the notification information and determines whether or not the first module unit 11, which has the same access class value as the identified access class recorded, is being used (S12).

[0029] If the switching unit 14 determines that it is not using the first module unit 11 which has the same access class recorded as the value of the identified access class (S12, No), it returns to step S11 and the subsequent processing is carried out.

[0030] Furthermore, if the switching unit 14 determines that it is using the first module unit 11 which has the same access class value as the identified access class recorded (S12, Yes), it executes a switching process to the second module unit 12 which has an access class value different from the identified access class recorded from among the multiple module units (S13).

[0031] Finally, the communication unit 13 uses the second module unit 12 to connect to the base station and communicate with other terminal devices.

[0032] (Effect of the module switching method for terminal device 1) As described above, in the module switching method S1, if the switching unit 14 is using the first module unit 11 which has the same access class value as the identified access class recorded, it executes a switching process to the second module unit 12 which has an access class value different from the identified access class recorded from among the multiple module units. Therefore, even if outgoing call restrictions are imposed, communication can be performed between communication terminals.

[0033] [Second exemplary embodiment] A second exemplary embodiment, which is an example of an embodiment of the present invention, will be described in detail with reference to the drawings. Components having the same function as those described in the above-described exemplary embodiment are denoted by the same reference numerals, and their descriptions are omitted as appropriate. The scope of application of each technical means adopted in this exemplary embodiment is not limited to this exemplary embodiment. That is, each technical means adopted in this exemplary embodiment can also be adopted in other exemplary embodiments included in this disclosure, to the extent that no particular technical hindrance occurs. Furthermore, each technical means shown in each drawing referenced to describe this exemplary embodiment can also be adopted in other exemplary embodiments included in this disclosure, to the extent that no particular technical hindrance occurs.

[0034] (Configuration of terminal device 1A) The configuration of terminal device 1A will be described with reference to Figure 3. Figure 3 is a block diagram showing the configuration of terminal device 1A. This terminal device 1A comprises a first module unit 11, a second module unit 12, a communication unit 13, a switching unit 14A, and a display unit 15.

[0035] The first module 11 and the second module 12 each record different access class values. The first module 11 and the second module 12 may be, for example, a USIM card implemented in the terminal device 1, or software having equivalent functionality to a USIM card implemented in the terminal device 1. Hereinafter, the first module 11 and the second module 12 may also be referred to as USIM.

[0036] The communication unit 13 receives broadcast information from the base station. The communication unit 13 is the part that performs wireless communication with base stations such as eNB in ​​an LTE system or gNB in ​​5G.

[0037] The switching unit 14A identifies the access class subject to transmission restriction from the broadcast information, and if it is using the first module unit 11 which has the same access class value as the identified access class recorded, it performs a switching process to the second module unit 12 which has an access class with a different value from the identified access class recorded from among the multiple module units.

[0038] (Configuration of wireless communication system 100 including terminal device 1A) Figure 4 is a block diagram showing an example configuration of a wireless communication system 100 including a terminal device 1A according to this disclosure. As shown in Figure 4, the wireless communication system 100 comprises a first terminal device 1A-1, a second terminal device 1A-2, an EPC2, a first eNB3-1, a second eNB3-2, and a local EPC4.

[0039] The first terminal device 1A-1 is located within the area of ​​the first eNB3-1 and also within the area of ​​the second eNB3-2. The second terminal device 1A-2 is located only within the area of ​​the first eNB3-1.

[0040] Furthermore, the first terminal device 1A-1 has a first USIM (first module) 11 with access class "AC11" and a second USIM (second module) 12 with access class "AC12", and is assumed to be communicating using the first USIM 11 with access class "AC11".

[0041] Furthermore, the second terminal device 1A-2 also has a first USIM (first module) 11 with access class "AC11" and a second USIM (second module) 12 with access class "AC12", and is assumed to be communicating using the first USIM 11 with access class "AC11".

[0042] EPC2 is the core network in the LTE system, and it has an S1 connection with the first eNB3-1 and an S1 connection with the second eNB3-2. This enables communication between the second terminal device 1A-2 within the area of ​​the first eNB3-1 and the first terminal device 1A-1 within the area of ​​the second eNB3-2.

[0043] Local EPC4 is an EPC responsible for a smaller area compared to EPC2, and is installed in the same building as the first eNB3-1 or the second eNB3-2. The first eNB3-1 and the second eNB3-2 are pre-configured to make S1 connections to multiple EPCs (including local EPCs).

[0044] Figure 5 schematically illustrates the processing of terminal devices when a backhaul disconnection occurs between EPC2 and the first eNB3-1 and the second eNB3-2. As shown in the upper part of Figure 5, when a backhaul disconnection occurs between EPC2 and the first eNB3-1, the first eNB3-1 establishes an S1 connection with local EPC4. Similarly, when a backhaul disconnection occurs between EPC2 and the second eNB3-2, the second eNB3-2 establishes an S1 connection with local EPC4.

[0045] In this state, if the first eNB3-1 were to impose outgoing call restrictions, it would notify the restriction via broadcast information (SIB2). For example, if the first eNB3-1 were to impose outgoing call restrictions by setting the bit string of AC-BarringInfo in SIB2 to "10000", terminal devices with access class "AC11" would be subject to the restrictions.

[0046] When outgoing calls are restricted, communication between the first terminal device 1A-1 and the second terminal device 1A-2 becomes impossible. The first terminal device 1A-1 is located within the areas of both the first eNB3-1 and the second eNB3-2, and since communication via the first eNB3-1 is impossible, it switches from the first USIM11(AC11) to the second USIM12(AC12) and attempts to communicate with the second terminal device via the first eNB3-1, which is under outgoing call restriction.

[0047] On the other hand, since the second terminal device 1A-2 is located within the area of ​​the first eNB3-1, it performs a switching process from the first USIM11(AC11) to the second USIM12(AC12) and attempts to communicate with the first terminal device via the first eNB3-1.

[0048] As shown in the lower diagram of Figure 5, communication between the first terminal device 1A-1 and the second terminal device 1A-2 becomes possible when the first terminal device 1A-1 accesses the first eNB3-1 using the second USIM12(AC12), and the second terminal device 1A-2 accesses the first eNB3-1 using the second USIM12(AC12).

[0049] Figure 6 is a flowchart illustrating the processing procedure of the terminal device according to this disclosure. First, the switching unit 14A of the terminal device 1A determines whether or not there is an eNB for outgoing call restriction (S21). For example, since the first terminal device 1A-1 is located within the area of ​​both the first eNB3-1 and the second eNB3-2, the switching unit 14A of the first terminal device 1A-1 determines whether or not outgoing call restriction has been notified from the first eNB3-1 and the second eNB3-2. Also, since the second terminal device 1A-2 is located within the area of ​​the first eNB3-1, the switching unit 14A of the second terminal device 1A-2 determines whether or not outgoing call restriction has been notified from the first eNB3-1.

[0050] If there is no eNB for outgoing call restriction (S21, No), the switching unit 14A of terminal device 1A terminates processing. If there is an eNB for outgoing call restriction (S21, Yes), the switching unit 14A of terminal device 1A determines whether or not it has a USIM that records an access class other than the access class subject to outgoing call restriction (S22).

[0051] If the terminal device 1A does not have a USIM that records an access class other than the access class subject to outgoing call restrictions (S22, No), the switching unit 14A of the terminal device 1A terminates processing. If the terminal device 1A has a USIM that records an access class other than the access class subject to outgoing call restrictions (S22, Yes), the switching unit 14A of the terminal device 1A determines whether or not it has reached time Tn (S23). Note that multiple times (T1, T2, ..., Tn) are held as time Tn, and the switching process is executed at each of these times.

[0052] Here, time Tn is a time based on an absolute time obtained via the network, and the switching unit 14A performs the switching process in synchronization with a predetermined absolute time. This is to perform the switching process in synchronization with the terminal device of the communication partner, and any means are acceptable as long as the two terminal devices can perform the switching process in synchronization.

[0053] If it is not time Tn (S23, No), the switching unit 14A returns to step S23 and repeats the processing thereafter. If it is time Tn (S23, Yes), the switching unit 14A switches to a USIM that records an access class other than the access class that is subject to outgoing call restriction (S24). The terminal device 1A is assumed to have three or more USIMs, and the order of USIM switching is predetermined.

[0054] Next, the communication unit 13 of terminal device 1A determines whether or not it was able to communicate with the other terminal device (S25). If it was able to communicate with the other terminal device (S25, Yes), the switching unit 14A terminates processing.

[0055] Furthermore, if communication with the other terminal device is not possible (S25, No), the switching unit 14A of the terminal device 1A determines whether or not it has performed the switching process to all USIMs other than the USIM subject to regulation (S26).

[0056] If there are any USIMs that have not yet undergone the switching process (S26, No), the switching unit 14A returns to step S23 and repeats the process from there. If there are no USIMs that have not yet undergone the switching process (S26, Yes), the switching unit 14A switches to the default USIM, for example, a USIM with access class "AC11" (S27), and terminates the process.

[0057] Furthermore, the terminal device 1A may also include a display unit 15 that displays information about multiple USIMs (modules), and the switching unit 14A may perform a switching process to the USIM selected by the user from among the multiple USIMs displayed on the display unit 15. This ensures that the switching process prioritizes the USIM desired by the user. The display unit 15 may be configured, for example, as a touch panel.

[0058] Furthermore, multiple USIMs (modules) may support the same communication carrier, and each may have a different access class value recorded. This makes it possible to support users who have contracts with only a specific communication carrier.

[0059] In the above explanation, we described the case where a backhaul disconnection occurs between EPC2 and the first eNB3-1 and the second eNB3-2. However, even in cases where there is no backhaul disconnection, outgoing call restrictions may occur due to a shortage of network resources, so the present invention can be applied.

[0060] (Effect of terminal device 1A) As described above, in terminal device 1A, the switching unit 14A executes the switching process in synchronization with a predetermined absolute time. Therefore, it becomes possible for the two terminal devices to perform the switching process in synchronization.

[0061] Furthermore, the switching unit 14A performs the switching process to the USIM selected by the user from among the multiple USIMs displayed on the display unit 15. Therefore, the switching process is performed with priority given to the USIM desired by the user.

[0062] Multiple USIMs (modules) are compatible with the same telecommunications carrier, and each has a different access class value recorded. Therefore, it is possible to support users who have contracts with only a specific telecommunications carrier.

[0063] [Examples of implementation using software] Some or all of the functions of terminal devices 1,1A may be implemented by hardware such as integrated circuits (IC chips), or by software.

[0064] In the latter case, the terminal devices 1,1A are implemented by a computer that executes instructions for a program, which is software that implements each function. An example of such a computer (hereinafter referred to as computer C) is shown in Figure 7. Figure 7 is a block diagram showing the hardware configuration of computer C, which functions as the terminal devices 1,1A.

[0065] Computer C comprises at least one processor C1 and at least one memory C2. Memory C2 stores a program P for operating computer C as each of the above-mentioned systems. In computer C, the processor C1 reads program P from memory C2 and executes it, thereby realizing each of the functions of the terminal devices 1 and 1A.

[0066] For processor C1, for example, a CPU (Central Processing Unit), GPU (Graphic Processing Unit), DSP (Digital Signal Processor), MPU (Micro Processing Unit), FPU (Floating Point Number Processing Unit), PPU (Physics Processing Unit), TPU (Tensor Processing Unit), quantum processor, microcontroller, or a combination thereof can be used. For memory C2, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof can be used.

[0067] Computer C may also be equipped with RAM (Random Access Memory) for loading program P at runtime and for temporarily storing various data. Furthermore, computer C may be equipped with communication interfaces for sending and receiving data with other devices. Additionally, computer C may be equipped with input / output interfaces for connecting input / output devices such as keyboards, mice, displays, and printers.

[0068] Furthermore, program P can be recorded on a non-temporary, tangible recording medium M that is readable by computer C. Such a recording medium M could be, for example, tape, disk, card, semiconductor memory, or programmable logic circuitry. Computer C can acquire program P via such a recording medium M. Program P can also be transmitted via a transmission medium. Such a transmission medium could be, for example, a communication network or broadcast waves. Computer C can also acquire program P via such a transmission medium.

[0069] [Additional Note 1] This disclosure includes the technologies described in the following appendices. However, the present invention is not limited to the technologies described in the following appendices, and various modifications are possible within the scope of the claims.

[0070] (Note 1) Multiple module means, each recording a different value access class, A communication means for receiving broadcast information from a base station, The system includes a switching means that identifies an access class subject to transmission restrictions from the aforementioned notification information, and, if a first module means recording the same access class as the identified access class is being used, executes a switching process to a second module means recording an access class with a different value from the identified access class among the plurality of module means, The communication means uses the second module means to connect to the base station and communicate with other terminal devices. Terminal device.

[0071] (Note 2) The switching means executes the switching process in synchronization with the absolute time received via the communication means. The terminal device described in Appendix 1.

[0072] (Note 3) The terminal device further includes a display means for displaying information relating to the plurality of module means, The switching means performs a switching process to the second module means selected by the user from among the plurality of module means displayed on the display means. The terminal device described in Appendix 1.

[0073] (Note 4) The aforementioned multiple module means correspond to the same communication carrier, and each has a different access class value recorded. A terminal device as described in any of the appendices 1 to 3.

[0074] (Note 5) Receiving broadcast information from the base station, The process involves identifying the access class subject to transmission restrictions from the aforementioned notification information, and if a first module is being used that has the same access class value as the identified access class recorded, then switching to a second module from among multiple modules that has a different access class value than the identified access class recorded. This includes using the second module to connect to the base station and communicate with other terminal devices, Method for switching modules in terminal devices.

[0075] (Note 6) In executing the aforementioned switching process, The switching process is executed in synchronization with the received absolute time. The method for switching modules of the terminal device as described in Appendix 5.

[0076] (Note 7) In executing the aforementioned switching process, From the information on the multiple modules displayed, the system performs a switching process to the second module selected by the user. The method for switching modules of the terminal device as described in Appendix 5.

[0077] (Note 8) The aforementioned multiple modules correspond to the same communication carrier, and each has a different access class value recorded. The method for switching modules of the terminal device as described in any of the appendices 5 to 7. [Explanation of Symbols]

[0078] 1,1A Terminal device 2 EPC 3-1 First eNB 3-2 Second eNB 4. Local EPC 11. First module section (first USIM) 12. Second module section (second USIM) 13 Communications Department 14,14A switching section 15 Display section 100 Wireless Communication Systems

Claims

1. Multiple module means, each recording a different value access class, A communication means for receiving broadcast information from a base station, The system includes a switching means that identifies an access class subject to transmission restrictions from the aforementioned notification information, and, if a first module means recording the same access class as the identified access class is being used, executes a switching process to a second module means recording an access class with a different value from the identified access class among the plurality of module means, The communication means uses the second module means and connects to the base station to communicate with other terminal devices. Terminal device.

2. The switching means executes the switching process in synchronization with the absolute time received via the communication means. The terminal device according to claim 1.

3. The terminal device further includes a display means for displaying information relating to the plurality of module means, The switching means performs a switching process to the second module means selected by the user from among the plurality of module means displayed on the display means. The terminal device according to claim 1.

4. The aforementioned multiple module means correspond to the same communication carrier, and each has a different access class value recorded. The terminal device according to any one of claims 1 to 3.

5. Receiving broadcast information from the base station, The process involves identifying the access class subject to transmission restrictions from the aforementioned notification information, and if a first module is being used that has the same access class value as the identified access class recorded, then switching to a second module from among multiple modules that has a different access class value than the identified access class recorded. This includes using the second module and connecting to the base station to communicate with other terminal devices, Method for switching modules in terminal devices.

6. In executing the aforementioned switching process, The switching process is executed in synchronization with the received absolute time. A method for switching modules of a terminal device according to claim 5.

7. In executing the aforementioned switching process, From the information on the multiple modules displayed, the system executes a switching process to the second module selected by the user. A method for switching modules of a terminal device according to claim 5.

8. The aforementioned multiple modules correspond to the same communication carrier, and each has a different access class value recorded. A method for switching modules of a terminal device according to any one of claims 5 to 7.

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