Communication device, base station, and communication method

Abstract

A communication device (100), which can communicate with a plurality of networks (200) by using a plurality of subscriber identification modules, comprises: a control unit (130) that, if the communication device is communicating with a first network (200A), temporarily restricts the communication capability of the communication device, which is used for communication with a second network (200B); and a communication unit (120) that transmits, to the second network, restriction information for temporarily restricting the communication capability of the communication device.

Description

Communication device, base station, and communication method CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims the benefit of priority from patent application serial number 2022-126647, filed August 8, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a communication device, a base station, and a communication method used in a mobile communication system.

[0003] In Release 18 of 3GPP (registered trademark; the same applies hereinafter) (3rd Generation Partnership Project), a standardization project for mobile communication systems, a work item has been launched to define a function for a communication device having two transceivers to communicate with multiple networks using multiple subscriber identity modules.

[0004] When such a communication device uses two transceivers for communication with a certain network (hereinafter referred to as the first network), if one of the transceivers is arbitrarily switched to communicate with another network (hereinafter referred to as the second network), the first network may communicate with the communication device without knowing that one of the transceivers has been switched, which may result in data loss between the communication device and the first network.

[0005] Therefore, in 3GPP Release 18, consideration is being given to temporarily limiting the communication capabilities of a communication device used to communicate with a first network so that one of the transceivers can be used to communicate with a second network (see non-patent document 1).

[0006] 3GPP contribution “RP-220955”

[0007] A communication device according to a first aspect is a communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, and includes a control unit that temporarily restricts a communication capability of the communication device used for communication with a second network when communicating with a first network, and a communication unit that transmits restriction information for temporarily restricting the communication capability to the second network.

[0008] A base station according to a second aspect is a base station of a network in a mobile communication system having wireless communication with a communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, and includes a communication unit that receives restriction information from the communication device communicating with another network, the restriction information being used to temporarily restrict the communication capability of the communication device used to communicate with the other network.

[0009] A communication method according to a third aspect is a communication method executed by a communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, the communication method comprising the steps of temporarily restricting a communication capability of the communication device used for communication with a second network when communicating with a first network, and transmitting restriction information for temporarily restricting the communication capability to the second network.

[0010] Objects, features, advantages, etc. of the present disclosure will become clearer from the following detailed description with reference to the accompanying drawings. FIG. 1 is a diagram illustrating an example configuration of a mobile communication system according to an embodiment. FIG. 2 is a diagram illustrating an example configuration of a protocol stack of the mobile communication system according to an embodiment. FIG. 3 is a diagram (part 1) for describing an assumed scenario. FIG. 4 is a diagram (part 2) for describing an assumed scenario. FIG. 5 is a diagram illustrating an example configuration of a UE (user equipment) according to an embodiment. FIG. 6 is a diagram illustrating an example configuration of a base station according to an embodiment. FIG. 7 is a sequence diagram (part 1) illustrating a first operation example according to an embodiment. FIG. 8 is a sequence diagram (part 2) illustrating the first operation example according to an embodiment. FIG. 9 is a diagram (part 1) for describing information elements in the first operation example according to an embodiment. FIG. 10 is a diagram (part 2) for describing information elements in the first operation example according to an embodiment. FIG. 11 is a diagram (part 3) for describing information elements in the first operation example according to an embodiment. FIG. 12 is a sequence diagram illustrating a second operation example according to an embodiment. FIG. 13 is a diagram illustrating information elements in the second operation example according to an embodiment.

[0011] A mobile communication system according to an embodiment will be described with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0012] However, currently, existing 3GPP technical specifications do not provide a specific mechanism for temporarily restricting the communication capability used for communication with a second network when a communication device communicates with a first network while communicating with a second network. Therefore, there is a concern that the network cannot recognize that the communication device wishes to temporarily restrict its communication capability, and that the communication device and the network cannot be properly synchronized regarding the temporary restriction of communication capability.

[0013] Therefore, one of the objects of the present disclosure is to provide a communication device, a base station, and a communication method that enable a network that communicates with a communication device that can communicate with multiple networks using multiple subscriber identity modules to recognize temporary limitations in the communication capabilities of the communication device.

[0014] [Embodiment] (System Configuration) The configuration of a mobile communication system 1 according to an embodiment will be described with reference to Fig. 1. In the following, an example in which the mobile communication system 1 is a fifth-generation system (5G / NR: New Radio) conforming to the 3GPP standard will be mainly described, but a fourth-generation system (4G / LTE: Long Term Evolution) system and / or a sixth-generation system may also be applied at least in part to the mobile communication system 1.

[0015] As shown in FIG. 1, a mobile communication system 1 according to the embodiment includes a user equipment (UE) 100, a first network 200A, and a second network 200B.

[0016] The UE 100 is an example of a communication device. The UE 100 may be a mobile wireless communication device. The UE 100 may be a device used by a user. For example, the UE 100 may be a mobile phone terminal (including a smartphone), a tablet terminal, a notebook PC, a communication module (including a communication card or a chipset), a sensor or a device provided in a sensor, a vehicle or a device provided in a vehicle (e.g., a Vehicle UE), or an aircraft or a device provided in an aircraft (e.g., an Aerial UE). The UE 100 may be referred to by other names such as a mobile station, a mobile terminal, a mobile device, a mobile unit, a subscriber station, a subscriber terminal, a subscriber device, a subscriber unit, a wireless station, a wireless terminal, a wireless device, a wireless unit, a remote station, a remote terminal, a remote device, or a remote unit.

[0017] The UE 100 can communicate with multiple networks using multiple subscriber identity modules (SIMs). The UE 100 may be a multi-SIM device that supports multiple SIMs. While an example in which the UE 100 supports two SIMs will be mainly described below, the UE 100 may also support three or more SIMs. "Supporting multiple SIMs" means that the UE 100 has the ability to handle multiple SIMs, and does not necessarily require that the UE 100 be equipped with multiple SIMs. Such a UE 100 may be referred to as a "UE that supports multiple SIMs." The SIM is not limited to a card-type SIM (a so-called SIM card), but may also be an embedded SIM (a so-called eSIM) that is previously embedded in the UE 100. The SIM is sometimes called a USIM (Universal Subscriber Identity Module).

[0018] The first network 200A is a network associated with one SIM of the UE 100. The second network 200B is a network associated with the other SIM of the UE 100. The UE 100 performs location registration with the first network 200A using one SIM, and performs location registration with the second network 200B using the other SIM. That is, the UE 100 is present in each of the first network 200A and the second network 200B. The first network 200A and the second network 200B may be networks of different telecommunications carriers. However, the first network 200A and the second network 200B may be networks of the same telecommunications carrier. Different PLMN (Public Land Mobile Network) IDs may be assigned to the first network 200A and the second network 200B.

[0019] The first network 200A includes a base station 210A constituting a radio access network and a core network 220A. The core network 220A includes, as core network devices, a mobility management device 221A and a gateway device 222A. Similarly, the second network 200B includes a base station 210B constituting a radio access network and a core network 220B. The core network 220B includes, as core network devices, a mobility management device 221B and a gateway device 222B. Hereinafter, when there is no need to distinguish between the base stations 210A and 200B, they will be simply referred to as base station 210; when there is no need to distinguish between the mobility management devices 221A and 221B, they will be simply referred to as mobility management device 221; and when there is no need to distinguish between the gateway devices 222A and 222B, they will be simply referred to as gateway device 222.

[0020] The base station 210 is a wireless communication device that performs wireless communication with the UE 100. The base station 210 manages one or more cells. The base station 210 performs wireless communication with the UE 100 that has established a connection with its own cell in the radio resource control (RRC) layer. The base station 210 has a radio resource management (RRM) function, a user data (hereinafter simply referred to as "data") routing function, a measurement control function for mobility control and scheduling, and the like. The term "cell" is used to indicate the smallest unit of a wireless communication area. The term "cell" is also used to indicate a function or resource for performing wireless communication with the UE 100. One cell belongs to one carrier frequency. FIG. 1 shows an example in which the base station 210A manages the cell C1 and the base station 210B manages the cell C2. The UE 100 is located in the overlapping area of ​​the cells C1 and C2.

[0021] The base station 210 may be a gNB, which is a 5G / NR base station, or an eNB, which is a 4G / LTE base station. The following mainly describes an example in which the base station 210 is a gNB. The base station 210 may be functionally divided into a CU (Central Unit) and a DU (Distributed Unit). The base station 210 may be a relay node such as an IAB (Integrated Access and Backhaul) node.

[0022] The mobility management device 221 is a device corresponding to the control plane and performs various mobility management for the UE 100. The mobility management device 221 communicates with the UE 100 using NAS (Non-Access Stratum) signaling and manages information on the tracking area in which the UE 100 is located. The mobility management device 221 performs paging through the base station 210 to notify the UE 100 of an incoming call. The mobility management device 221 may be a 5G / NR AMF (Access and Mobility Management Function) or a 4G / LTE MME (Mobility Management Entity).

[0023] The gateway device 222 is a device corresponding to the user plane and controls the transfer of data of the UE 100. The gateway device 222 may be a 5G / NR UPF (User Plane Function) or a 4G / LTE S-GW (Serving Gateway).

[0024] (Configuration Example of Protocol Stack) With reference to Fig. 2, a configuration example of a protocol stack of the mobile communication system 1 will be described. As shown in Fig. 2, the protocol of the wireless section between the UE 100 and the base station 210 has a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC) layer.

[0025] The PHY layer performs encoding / decoding, modulation / demodulation, antenna mapping / demapping, and resource mapping / demapping. Data and control information are transmitted between the PHY layer of the UE 100 and the PHY layer of the base station 210 via a physical channel.

[0026] The MAC layer performs data priority control, retransmission processing using Hybrid ARQ (HARQ), random access procedures, etc. Data and control information are transmitted between the MAC layer of UE 100 and the MAC layer of base station 210 via a transport channel. The MAC layer of base station 210 includes a scheduler. The scheduler determines the uplink and downlink transport format (transport block size, modulation and coding scheme (MCS)) and the resources to be allocated to UE 100.

[0027] The RLC layer transmits data to the RLC layer on the receiving side using the functions of the MAC layer and the PHY layer. Data and control information are transmitted between the RLC layer of the UE 100 and the RLC layer of the base station 210 via logical channels.

[0028] The PDCP layer performs header compression / decompression and encryption / decryption.

[0029] A Service Data Adaptation Protocol (SDAP) layer may be provided as an upper layer above the PDCP layer. The SDAP layer maps IP flows, which are units for Quality of Service (QoS) control by the core network, to radio bearers, which are units for QoS control by an Access Stratum (AS).

[0030] The RRC layer controls logical channels, transport channels, and physical channels according to the establishment, re-establishment, and release of radio bearers. RRC signaling for various settings is transmitted between the RRC layer of the UE 100 and the RRC layer of the base station 210. When an RRC connection exists between the RRC of the UE 100 and the RRC of the base station 210, the UE 100 is in an RRC connected state. When there is no RRC connection between the RRC of the UE 100 and the RRC of the base station 210, the UE 100 is in an RRC idle state. When the RRC connection between the RRC of the UE 100 and the RRC of the base station 210 is suspended, the UE 100 is in an RRC inactive state.

[0031] The NAS layer, which is positioned above the RRC layer, performs session management and mobility management for the UE 100. NAS signaling is transmitted between the NAS layer of the UE 100 and the NAS layer of the mobility management device 221.

[0032] The modes (NAS states) in the NAS layer of UE 100 include idle mode and connected mode. In connected mode, context information of UE 100 is held in the network, and in idle mode, context information of UE 100 is not held in the network. When UE 100 is in connected mode, UE 100 is in an RRC connected state or an RRC inactive state. When UE 100 is in idle mode, UE 100 is in an RRC idle state.

[0033] The mode at the NAS layer may be a 5G Mobility Management (5GMM) mode, in which the connected mode may be a 5GMM-connected mode and the idle mode may be a 5GMM-idle mode.

[0034] The UE 100 has an application layer and the like in addition to the radio interface protocol.

[0035] 3 and 4, an assumed scenario in the mobile communication system 1 according to the embodiment will be described. In Release 18 of 3GPP, which is a standardization project for the mobile communication system 1, a work item has been launched to define a function in which the UE 100 having two transceivers communicates with multiple networks using multiple SIMs.

[0036] For example, as shown in Fig. 3A , when UE 100 communicates with first network 200A using SIM 111, UE 100 can use first transceiver unit 121 and second transceiver unit 122 for communication with first network 200A. As shown in Fig. 3B , when UE 100 communicates with second network 200B using SIM 112, it is assumed that UE 100 switches second transceiver unit 122 for communication with second network 200B. This allows UE 100 to communicate with second network 200B using second transceiver unit 122 while maintaining communication with first network 200A using first transceiver unit 121.

[0037] Here, when UE100 uses two transceivers for communication with the first network 200A, if it arbitrarily switches one of the transceivers (e.g., the second transceiver 122) for communication with the second network 200B, data loss may occur between UE100 and the first network 200A because the first network 200A communicates with UE100 without knowing that the second transceiver 122 has been switched.

[0038] Therefore, in 3GPP Release 18, it is being considered to temporarily limit the communication capabilities of UE 100 used for communication with the first network 200A so that one of the transceivers can be used for communication with the second network 200B.

[0039] However, currently, in the existing 3GPP technical specifications, there is no specific mechanism for temporarily restricting the communication capability used for communication with the second network 200B when the UE 100 communicates with the first network 200A while communicating with the second network 200B. Therefore, there is a concern that the second network 200B cannot recognize that the UE 100 desires to temporarily restrict the communication capability, and that the temporary restriction of the communication capability cannot be appropriately synchronized between the UE 100 and the second network 200B.

[0040] For example, in a case where the UE 100 uses the first transceiver unit 121 for communication with the first network 200A and can therefore only use the second transceiver unit 122 for communication with the second network 200B, the second network 200B may communicate with the UE 100 without knowing that the UE 100 can only use the second transceiver unit 122, which may result in data loss between the UE 100 and the second network 200B. In an embodiment described later, an operation will be described that enables the second network 200B, which communicates with the UE 100 that can communicate with a plurality of networks using a plurality of SIMs, to recognize temporary restrictions on the communication capabilities of the UE 100.

[0041] Furthermore, as shown in Figures 4A and 4B, it is assumed that when UE 100 uses the first transceiver unit 121 for communication with the first network 200A and the second transceiver unit 122 for communication with the second network 200B, when UE 100 ends communication with the first network 200A, it switches the first transceiver unit 121 to communication with the second network 200B.

[0042] However, currently, in the existing 3GPP technical specifications, there is no specific mechanism for a UE 100 that has temporarily restricted communication capabilities used for communication with a first network 200A and a second network 200B to release or change the restriction on the communication capabilities of the UE 100 between the UE 100 and the second network 200B, for example, after the UE 100 ends communication with the first network 200A. For this reason, there is a concern that the second network 200B cannot recognize that the UE 100 wishes to release or change the temporary restriction on the communication capabilities, and that appropriate synchronization regarding the temporary restriction on the communication capabilities cannot be achieved between the UE 100 and the second network 200B. In one embodiment described below, an operation will be described that enables a network that communicates with a UE 100 that can communicate with multiple networks using multiple SIMs to recognize the temporary restriction on the communication capabilities of the UE 100.

[0043] In the existing 3GPP technical specifications, there is no specific mechanism for temporarily limiting the communication capability of the UE 100 used for communication with a network, and therefore there is a concern that the UE 100 may not be able to appropriately limit the communication capability. In one embodiment described later, an operation for enabling the UE 100, which can communicate with a plurality of networks using a plurality of SIMs, to appropriately limit the communication capability will be described.

[0044] (Example of UE configuration) An example of the configuration of UE 100 will be described with reference to Fig. 4. As shown in Fig. 4, UE 100 has antenna 101, antenna 102, SIM 111, SIM 112, communication unit 120, and control unit 130. Antenna 101 and antenna 102 may be provided outside UE 100. SIM 111 and SIM 112 may be SIM cards or eSIMs.

[0045] The SIM 111 stores subscriber information and setting information necessary for the UE 100 to communicate with the first network 200A. The SIM 111 stores identification information of the UE 100 in the first network 200A, such as a telephone number and an IMSI (International Mobile Subscriber Identity). The SIM 111 corresponds to a first subscriber information module. The UE 100 communicates with the first network 200A using the SIM 111.

[0046] The SIM 112 stores subscriber information and setting information necessary for the UE 100 to communicate with the second network 200B. The SIM 112 stores identification information of the UE 100 in the second network 200B, such as a telephone number and an IMSI. The SIM 112 corresponds to a second subscriber information module. The UE 100 communicates with the second network 200B using the SIM 112.

[0047] The communication unit 120, under the control of the control unit 130, performs wireless communication with the first network 200A and the second network 200B via the antenna 101 and the antenna 102. The communication unit 120 has a plurality of transceivers. The transceivers may be referred to as transceivers or as radio frequency (RF) chains. In this embodiment, the communication unit 120 has a first transceiver 121 and a second transceiver 122. The first transceiver 121 and the second transceiver 122 each have a receiving unit 120R and a transmitting unit 120T. The receiving unit 120R converts radio signals received by each antenna into received signals, which are baseband signals, performs signal processing on the received signals, and outputs the received signals to the control unit 130. The transmitting unit 120T performs signal processing on transmission signals, which are baseband signals, output by the control unit 130, converts the transmitted signals into radio signals, and transmits the radio signals from each antenna. The receiving unit 120R may be referred to as a receiver, an Rx chain, or an Rx branch. The transmitting unit 120T may be referred to as a transmitter, a Tx chain, or a Tx branch. In this embodiment, the first transceiver unit 121 has a first receiving unit 121R as the receiving unit 120R and a first transmitting unit 121T as the transmitting unit 120T. The second transceiver unit 122 has a second receiving unit 122R as the receiving unit 120R and a second transmitting unit 122T as the transmitting unit 120T.

[0048] The control unit 130 controls the communication unit 120 and performs various controls in the UE 100. The control unit 130 controls communication with the first network 200A using the SIM 111 and controls communication with the second network 200B using the SIM 112. The control unit 130 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in processing by the processor. The memory may include at least one of ROM (Read Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), RAM (Random Access Memory), and flash memory. The processor may include a digital signal processor (DSP) that performs digital processing of digital signals, and a central processing unit (CPU) that executes programs. Note that a portion of the memory may be provided in the communication unit 120. The DSP may also be provided in the communication unit 120.

[0049] The control unit 130 includes an RRC processing unit 131 and a NAS processing unit 132. The RRC processing unit 131 performs processing in the RRC layer. The NAS processing unit 132 performs processing in the NAS layer, which is a layer higher than the RRC layer. The RRC processing unit 131 and the NAS processing unit 132 may be configured by a single processor or by multiple processors.

[0050] The UE 100 configured in this manner is capable of communicating with multiple networks using multiple SIMs. The control unit 130 temporarily restricts the communication capability of the UE 100 used for communication with the second network 200B when communicating with the first network 200A. The communication unit 120 transmits restriction information for temporarily restricting the communication capability of the UE 100 used for communication with the second network 200B to the second network 200B. This allows the second network 200B to recognize the temporary restriction on the communication capability of the UE 100 based on the restriction information. This makes it easier to appropriately synchronize the UE 100 and the second network 200B regarding the temporary restriction on the communication capability.

[0051] In addition, the operation of the functional units of UE100 (specifically, at least one of antenna 101, antenna 102, SIM 111, SIM 112, communication unit 120, and control unit 130 (e.g., RRC processing unit 131 and NAS processing unit 132)) may be described as the operation of UE100.

[0052] (Configuration Example of Base Station) An example configuration of the base station 210A of the first network 200A will be described with reference to Fig. 5. Note that the base station 210B of the second network 200B has the same configuration as the base station 210A, and therefore its description will be omitted. As shown in Fig. 5, the base station 210A has an antenna 211, a wireless communication unit 212, a network communication unit 213, and a control unit 214.

[0053] The wireless communication unit 212 communicates with the UE 100 via the antenna 211 under the control of the control unit 214. The wireless communication unit 212 has a receiving unit 212R and a transmitting unit 212T. The receiving unit 212R converts the wireless signal received by the antenna 211 into a received signal, which is a baseband signal, performs signal processing on the received signal, and outputs the received signal to the control unit 214. The transmitting unit 212T performs signal processing on the transmission signal, which is a baseband signal, output by the control unit 214, converts the transmission signal into a wireless signal, and transmits the wireless signal from the antenna 211.

[0054] The network communication unit 213 is connected to the core network 220A. Under the control of the control unit 214, the network communication unit 213 performs network communication with the mobility management device 221A and the gateway device 222A.

[0055] The control unit 214 controls the wireless communication unit 212 and performs various controls in the base station 210A. The control unit 214 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in processing by the processor. The memory may include at least one of ROM, EPROM, EEPROM, RAM, and flash memory. The processor may include a digital signal processor (DSP) that performs digital processing of digital signals and a central processing unit (CPU) that executes programs. Note that a portion of the memory may be provided in the wireless communication unit 212. The DSP may also be provided in the wireless communication unit 212.

[0056] In the base station 210 configured in this manner, the wireless communication unit 212 receives, from the UE 100 communicating with another network, restriction information for temporarily restricting the communication capability of the UE 100 used for communication with the second network 200B. This allows the second network 200B to recognize the temporary restriction on the communication capability of the UE 100 based on the restriction information. This makes it easier to appropriately synchronize the UE 100 and the second network 200B regarding the temporary restriction on the communication capability.

[0057] The operation of the functional units (specifically, at least one of the antenna 211, the wireless communication unit 212, the network communication unit 213, and the control unit 214) of the base station 210A may be described as the operation of the base station 210A.

[0058] (Operation of Mobile Communication System) (1) First Operation Example A first operation example of the mobile communication system 1 will be described with reference to FIGS. 7 to 12 . In this operation example, the UE 100 is present in the primary cell (P cell) 210P and the secondary cell (S cell) 210S of the first network 200A. One base station 210A of the first network 200A may manage the P cell 210P and the S cell 210S. Alternatively, one base station 210A of the first network 200A may manage the P cell 210P, and another base station 210A of the first network 200A may manage the S cell 210S. Note that the P cell 210P may be a P cell in carrier aggregation operation. Also, the S cell 210S may be an S cell in carrier aggregation operation. Also, the P cell 210P may be a P cell belonging to a master cell group (MCG) in dual connectivity operation. The S cell 210S may also be a primary secondary cell (PS cell) belonging to a secondary cell group (SCG) in dual connectivity operation. The S cell 210S may also be a secondary cell (S cell) belonging to a master cell group (MCG) and / or a secondary cell group (SCG) in dual connectivity operation.

[0059] Here, in dual connectivity operation, a P cell of a master cell group (MCG) and / or a primary secondary cell (PS cell) belonging to a secondary cell group (SCG) is also referred to as a special cell (SP cell). Also, in dual connectivity operation, a MAC entity may be associated with each of the master cell group (MCG) and the secondary cell group (SCG).

[0060] Hereinafter, for ease of explanation, in this embodiment, a P cell belonging to a master cell group (MCG) will also be referred to as a P cell. Also, a primary secondary cell (PS cell) belonging to a secondary cell group (SCG) will also be referred to as a secondary cell. That is, in this embodiment, a P cell may be replaced with a P cell belonging to the master cell group (MCG). Also, in this embodiment, a secondary cell may be replaced with a primary secondary cell (PS cell) and / or a secondary cell (S cell) belonging to a secondary cell group (SCG).

[0061] 7 , the UE 100 is in an RRC connected state in the first network 200A. In the RRC connected state, the UE 100 has an RRC connection established between the first network 200A and the UE 100. Therefore, the control unit 130 of the UE 100 and the control unit 214 of the base station 210 perform control to establish an RRC connection between the UE 100 and the base station 210.

[0062] Furthermore, the UE 100 is communicating with the first network 200A. The UE 100 is communicating in the first network 200A. For example, the UE 100 is provided with a service such as a voice call from the first network 200A. Note that "in communication" means that the UE 100 is at least in an RRC connected state in the network. Therefore, when the UE 100 is communicating with the first network 200A, the UE 100 is continuously exchanging data with the network, either continuously or discontinuously.

[0063] 7, the UE 100 is in an RRC idle state or an RRC inactive state in the second network 200B. The UE 100 monitors paging from the second network 200B and receives system block information from the second network 200B while maintaining an RRC connected state in the first network 200A. For example, the UE 100 can monitor paging and receive system block information in the second network 200B during a period in which communication with the first network 200A is interrupted.

[0064] Hereinafter, the communication between the UE 100 and the base station 210A may be, for the UE 100, communication between the UE 100 and the cell of the base station 210A (specifically, the P cell 210P, the S cell 210S), that is, communication between the cell in which the UE 100 is located. The same applies to the communication between the UE 100 and the base station 210B. Furthermore, the communication between the UE 100 and a node belonging to the first network 200A (for example, the base station 210A (i.e., the P cell 210P, the S cell 210S), the mobility management device 221A, the gateway device 222A) may be referred to as the communication between the UE 100 and the first network 200A. The same applies to the communication between the UE 100 and a node belonging to the second network 200B.

[0065] Furthermore, in the following, UE 100 communicates with first network 200A (specifically, transmitting and receiving / notifying messages, etc.) via communication unit 120 (receiving unit 120R and / or transmitting unit 120T), but for ease of explanation, the description of communication via communication unit 120 will be omitted as appropriate. Similarly, the description of communication between UE 100 and second network 200B will be omitted as appropriate as communication via communication unit 120. Therefore, the transmission and / or reception of messages, etc. by UE 100 may be the transmission and / or reception of messages, etc. by communication unit 120 (receiving unit 120R and / or transmitting unit 120T) of UE 100.

[0066] Step S101: In the second network 200B, the AMF 221B transmits, to the base station 210B, a paging request requesting transmission of a paging message addressed to the UE 100. The network communication unit 213 of the base station 210B receives the paging request.

[0067] The paging request may include paging cause information indicating the reason for the paging, such as whether the reason for the paging is a voice call.

[0068] Step S102: In response to receiving the paging request, the radio communication unit 212 of the base station 210B transmits a paging message (Paging) addressed to the UE 100. The RRC processing unit 131 (receiving unit 120R) of the UE 100 receives the paging message from the base station 210B. The RRC processing unit 131 receives the paging message from the base station 210B when the UE 100 is in an RRC idle state or an RRC inactive state in the second network 200B during communication with the first network 200A. The UE 100 may receive the paging message via the first transceiver unit 121 or via the second transceiver unit 122.

[0069] The paging message is used to notify one or more UEs 100. The paging message is a message of the RRC layer. The paging message includes, for example, the ID of the UE 100. More specifically, for example, the paging message includes a list of paging records, and one paging record in the list includes the ID of the UE 100. For example, the ID is the 5G-S-TMSI or full I-RNTI (Inactive Radio Network Temporary Identifier) ​​of the UE 100. The paging message may include paging cause information (Paging Cause). For example, the paging cause information may specify that the cause of the paging is a voice service. The paging cause information may be associated with, for example, the ID of the UE 100.

[0070] The RRC processing unit 131 may perform the processing of step S103 when the paging message includes the ID of UE 100 and UE 100 is in an RRC inactive state or an RRC idle state in the second network 200B while communicating with the first network 200A.

[0071] If the paging message includes the ID of UE100 and UE100 is not communicating with the first network 200A, for example, if UE100 is in an RRC idle state or an RRC inactive state for the first network 200A, the RRC processing unit 131 may not perform the processing of step S103 and may instead perform the specified processing when a paging message is received.

[0072] Step S103: The RRC processing unit 131 provides a paging reception notification to the NAS processing unit 132. The NAS processing unit 132 receives the paging reception notification from the RRC processing unit 131. The paging reception notification is for notifying the UE 100 that it has received a paging. The RRC processing unit 131 may use the paging reception notification to indicate to the NAS processing unit 132 that it has received a paging message in the second network 200B.

[0073] The paging reception notification may include paging cause information (Paging Cause). Note that, for example, when the UE 100 is in an RRC inactive state or an idle state, the paging reception notification may include an identifier (UE ID) of the UE 100.

[0074] In response to receiving the paging message, the control unit 130 may determine whether to temporarily restrict the communication capability of the UE 100 used for communication with the first network 200A. The control unit 130 may determine whether to temporarily restrict the communication capability based on, for example, paging cause information. For example, when the paging cause information indicates a voice service, the control unit 130 may determine to temporarily restrict the communication capability. When the paging cause information indicates a service other than a voice service, the control unit 130 may determine not to temporarily restrict the communication capability.

[0075] Furthermore, the control unit 130 may determine whether to temporarily restrict the communication capability based on, for example, an input from a user. For example, the control unit 130 may determine whether to temporarily restrict the communication capability when the user input recommends communication with the second network 200B. The control unit 130 may determine not to temporarily restrict the communication capability when the user input does not recommend communication with the second network 200B or when there is no user input recommending communication with the second network 200B for a predetermined period after receiving a paging.

[0076] The determination may be made in the NAS processing unit 132, or may be made in a layer higher than the NAS processing unit. When the determination is made in the higher layer, the determination result may be provided to the NAS processing unit 132.

[0077] When it is determined that the communication capability of the UE 100 used for communication with the first network 200A is to be temporarily restricted, the NAS processing unit 132 executes the process of step S104. On the other hand, when it is determined that the communication capability of the UE 100 used for communication with the first network 200A is not to be temporarily restricted, the control unit 130 may make the following determination without executing the process of step S104.

[0078] When the control unit 130 does not temporarily restrict the communication capability, the control unit 130 may determine, for example, based on the paging cause information, whether to prioritize communication with the first network 200A over communication with the second network 200B. When the control unit 130 prioritizes communication with the first network 200A, the control unit 130 may perform control to transmit to the second network 200B a notification that the control unit 130 will not respond to paging from the second network 200B. On the other hand, when the control unit 130 prioritizes communication with the second network 200B, the control unit 130 may perform control to transition from an RRC connected state in the first network 200A to an RRC idle state or an RRC inactive state, and transition to an RRC connected state in the second network 200B. The control unit 130 may establish an RRC connection with the second network 200B and perform communication with the second network 200B.

[0079] Step S104: The NAS processing unit 132 provides a capability restriction instruction to the RRC processing unit 131. The RRC processing unit 131 receives the capability restriction instruction from the NAS processing unit 132. The capability restriction instruction may be an instruction to transmit restriction information, which will be described later. The capability restriction instruction may indicate the content of the restriction information.

[0080] Step S105: The RRC processing unit 131 controls transmission of restriction information to the first network 200A for communication with the second network 200B. The communication unit 120 transmits the restriction information to the first network 200A for communication with the second network 200B. Specifically, the communication unit 120 transmits the restriction information to the P cell 210P. The communication unit 120 may transmit a message including the restriction information to the P cell 210P. The radio communication unit 212 of the base station 210A receives the restriction information from the UE 100 in the P cell 210P.

[0081] The restriction information is used to temporarily restrict the communication capability of the UE 100 used for communication with the first network 200A, for communication with the second network 200B. Note that the communication capability of the UE 100 does not simply refer to the capability of the UE 100, but may also be referred to as, for example, communication resources assigned to the UE 100, radio resources scheduled to the UE 100, etc. The communication capability to be temporarily restricted may be communication resources associated with a transceiver unit (i.e., a transmitter and / or a receiver) used for communication with the second network 200B.

[0082] As shown in FIG. 9 , the control unit 130 (e.g., the RRC processing unit 131) may include restriction information (e.g., MUSIM-ReducedCapability) in a Multi Universal Subscriber Identity Module (MUSIM) assistance information element (i.e., MUSIM-Assistance) used to provide MUSIM assistance information. The communication unit 120 may transmit the MUSIM assistance information including the restriction information to the first network 200A. The communication unit 120 may transmit a UE assistance information (i.e., UEAssistanceInformation) message including the MUSIM assistance information including the restriction information to the first network 200A. Note that the UE assistance information message is a message used for indicating the UE assistance information to the network. The MUSIM assistance information element may be, for example, information used for MUSIM operation that communicates with multiple networks using multiple SIMs.

[0083] As shown in E11 of FIG. 10, the control unit 130 may include at least one of information for restricting secondary cells, information for restricting frequency bands, and information for restricting multiple-input multiple-output (MIMO) layers as restriction information in the MUSIM auxiliary information element.

[0084] The information for restricting secondary cells may be, for example, information for restricting secondary cells for which data scheduling is possible. The information for restricting secondary cells may be, for example, information indicating a recommendation (preference) of UE 100 for a reduced configuration corresponding to the maximum number of secondary cells (specifically, reducedMaxCCs, ReducedMaxCCs). The information may be at least one of information indicating a recommendation (preference) of UE 100 for a reduced configuration corresponding to the maximum number of downlink secondary cells (specifically, reducedCCsDL) and information indicating a recommendation (preference) of UE 100 for a reduced configuration corresponding to the maximum number of uplink secondary cells (specifically, reducedCCsDL). That is, the information for restricting secondary cells may be information for restricting the maximum number of secondary cells. Here, as described above, the secondary cell may include a primary secondary cell. Furthermore, in the downlink, a cell may correspond to a downlink component carrier. Furthermore, in the uplink, a cell may correspond to an uplink component carrier. In this embodiment, configuring a cell may include configuring a downlink component carrier and / or configuring an uplink component carrier. For example, the information for restricting a secondary cell may include information for restricting the maximum number of component carriers configured in the downlink and / or information for restricting the maximum number of component carriers configured in the uplink.

[0085] The information for limiting the frequency band may be, for example, information for limiting a frequency band in which data can be scheduled. The information for limiting the frequency band may be information on a maximum frequency band (e.g., ReducedMaxBW-FRx), information on an aggregated bandwidth (e.g., ReducedAggregatedBandwidth), information on a maximum frequency band of FR1 (e.g., reducedMaxBW-FR1), or information on a maximum frequency band of FR2 (e.g., reducedMaxBW-FR2, reducedMaxBW-FR2-2). The information for limiting the frequency band may be, for example, information indicating a recommendation (preference) of the UE 100 for a reduced setting corresponding to the maximum aggregated bandwidth across all downlink carriers and all uplink carriers of FR1 (Frequency Range 1) (specifically, reducedBW-FR1), information indicating a recommendation of the UE 100 for a reduced setting corresponding to the maximum aggregated bandwidth across all downlink carriers and all uplink carriers of FR2-1 (Frequency Range 2-1) (specifically, reducedBW-FR2), and information indicating a recommendation of the UE 100 for a reduced setting corresponding to the maximum aggregated bandwidth across all downlink carriers and all uplink carriers of FR2-2 (Frequency Range 2-2) (specifically, reducedBW-FR2-2). In FR1, the subcarrier spacing is 15 or 30 kHz, in FR2-1 the subcarrier spacing is 120 or 240 kHz, and in FR2-2 the subcarrier spacing is 120, 480, or 960 kHz.

[0086] The information for limiting the MIMO layer may be, for example, information indicating a recommendation by UE 100 about a reduced setting corresponding to the maximum number of downlink MIMO layers or uplink MIMO layers of each serving cell operating in FR1 (specifically, reducedMaxMIMO-LayersFR1, reducedMIMO-LayersFR1-DL, reducedMIMO-LayersFR1-UL), information indicating a recommendation by UE 100 about a reduced setting corresponding to the maximum number of downlink MIMO layers or uplink MIMO layers of each serving cell operating in FR2-1 (specifically, is reducedMaxMIMO-LayersFR2, reducedMIMO-LayersFR2-DL, reducedMIMO-LayersFR2-UL), and information indicating a recommendation of UE100 for a reduction setting corresponding to the maximum number of downlink MIMO layers or uplink MIMO layers of each serving cell operating in FR2-2 (specifically, reducedMaxMIMO-LayersFR2-2, reducedMIMO-LayersFR2-2-DL, reducedMIMO-LayersFR2-2-UL). Here, the serving cell may include a primary cell and / or a secondary cell.

[0087] As shown at E12 in Fig. 10 , the control unit 130 may include, as restriction information, information indicating the number of transceivers (e.g., transceivers) available for communication with the first network 200A (which may be referred to as nrofRxBranches, for example), in the MUSIM auxiliary information element. The information may indicate the maximum number of transceivers available for communication with the first network 200A. Furthermore, the control unit 130 may include, as restriction information, at least one of information indicating the number (or maximum number) of transmitters (e.g., transmitters) available for communication with the first network 200A and information indicating the number (or maximum number) of receivers (e.g., receivers) available for communication with the first network 200A in the MUSIM auxiliary information element.

[0088] As shown in E13 of FIG. 10 , the control unit 130 may include flag information for deactivating or releasing a secondary cell (for example, this may be referred to as "deactivateSCG") in the MUSIM auxiliary information element as restriction information. The flag information may be, for example, information indicated by 1 bit. For example, when the flag information is set to "true", this may indicate deactivation of the secondary cell, release of the secondary cell, deactivation of a secondary cell group, or release of a secondary cell group. When the UE 100 is performing dual connectivity, the control unit 130 may include the flag information in the MUSIM auxiliary information element as restriction information. In dual connectivity, the UE 100 in the RRC connected state is configured to utilize radio resources provided by two different schedulers located at different locations in two different nodes (e.g., NG-RAN (Next Generation-Radio Access Network)) connected via a non-ideal backhaul.

[0089] Furthermore, the control unit 130 may include specified information to be set in the overheating assistance information element (i.e., OverheatingAssistance) when providing an overheating assistance indication for communication with the second network 200B. The control unit 130 may typically include the specified information in the overheating assistance information element based on whether internal overheating has been detected in the UE 100. However, the control unit 130 may include the specified information in the overheating assistance information element for communication with the second network 200B regardless of whether internal overheating has been detected in the UE 100. The specified information may be, for example, reducedMaxCCs, reducedMaxBW-FR1, reducedMaxBW-FR2, reducedMaxBW-FR2-2, reducedMaxMIMO-LayersFR1, reducedMaxMIMO-LayersFR2, and reducedMaxMIMO-LayersFR2-2, etc. Therefore, the communication unit 120 may transmit the overheating auxiliary information element to the first network 200A as restriction information for communication with the second network 200B, regardless of whether internal overheating has been detected or not.

[0090] Furthermore, the control unit 130 may include information for deactivating or releasing a secondary cell as restriction information in the UE assistance information message. Here, the control unit 130 may include the restriction information in an information element different from the MUSIM assistance information element among information elements included in the UE assistance information message. For example, the control unit 130 may include, for communication with the second network 200B, specified information (specifically, scg-DeactivationPreference) to be included in the UE assistance information based on recommending a secondary cell group to be deactivated. Therefore, the communication unit 120 may transmit information for deactivating or releasing a secondary cell to the first network 200A as restriction information.

[0091] The control unit 130 may include the restriction information in the following messages. For example, the restriction information may be included in a request message used for a request related to a radio resource control (RRC) connection. The request message may be, for example, an RRC setup request (RRCSetupRequest) message, an RRC re-establishment request (RRCReestablishmentRequest) message, an RRC resume request (RRCResumeRequest) message, and / or an RRC resume request 1 (RRCResumeRequest1) message. The RRC setup request message is a message for requesting establishment of an RRC connection. The RRC re-establishment request message is a message for requesting re-establishment of an RRC connection. The RRC resume request message and the RRC resume request 1 message are messages for requesting the resumption of a suspended RRC connection or for performing a Radio Access Network (RAN) based Notification Area (RNA) update.

[0092] Furthermore, the restriction information may be included in a completion message used to confirm successful completion of procedures related to a radio resource control (RRC) connection. The completion message may be, for example, an RRC Setup Complete (RRCSetupComplete) message (see E13), an RRC Reestablishment Complete (RRCReestablishmentComplete) message, and / or an RRC Resume Complete (RRCResumeComplete) message (see E14). The RRC Setup Complete message is a message used to confirm successful completion of establishment of an RRC connection. The RRC Reestablishment Complete message is a message used to confirm successful completion of re-establishment of an RRC connection. The RRC Resume Complete message is a message used to confirm successful completion of resumption of an RRC connection.

[0093] In addition, the restriction information may be included in a UE information response (UEInformationResponse) message for transmitting the requested information to the network. Note that the UE 100 transmits the UE information response message based on a UE information request (UEInformationRequest) message from the network. The UE information request message is a message used by the network to retrieve information from the UE 100.

[0094] Note that, when the UE 100 is performing simultaneous parallel communication with the first network 200A using a plurality of transceivers, the communication unit 120 may transmit the restriction information to the first network 200A. The UE 100 may transmit the restriction information to the first network 200A when all of the transceivers are being used for the communication, or may transmit the restriction information to the first network 200A when a plurality of transceivers are being used even when some of the transceivers are not being used for the communication.

[0095] The control unit 214 of the base station 210A may determine, based on the restriction information, whether to temporarily restrict the communication capability of the UE 100 used for communication with the first network 200A. When the control unit 214 of the base station 210A determines to temporarily restrict the communication capability of the UE 100, the control unit 214 may execute the process of step S106. When the control unit 214 of the base station 210A determines not to temporarily restrict the communication capability of the UE 100, the control unit 214 may end the process.

[0096] Step S106: The network communication unit 213 of the base station 210A that manages the P cell 210P may transmit a scheduling stop instruction to another base station 210A that manages the S cell 210S. When the base station 210A manages the P cell 210P and the S cell 210S, the base station 210A may send the scheduling stop instruction from the entity that manages the P cell 210P to the entity that manages the S cell 210S within the control unit 214.

[0097] The scheduling stop instruction may be for stopping the scheduling assigned to the UE 100, or may be for stopping a part of the scheduling assigned to the UE 100. The scheduling stop instruction may include at least a part of the information of the restriction information.

[0098] Based on the scheduling stop instruction, the control unit 214 of the base station 210A that manages the S cell 210S may temporarily limit the communication capability of the UE 100. The network communication unit 213 of the base station 210A may transmit a response message indicating that scheduling will be stopped to the base station 210A that manages the P cell 210P. Based on the reception of the response message, the control unit 214 of the base station 210A that manages the P cell 210P may execute the process of step S107.

[0099] Step S107: In the P cell 210P, the radio communication unit 212 of the base station 210A transmits to the UE 100 a message (for example, an RRC reconfiguration message) including configuration information for temporarily restricting the communication capability of the UE 100. The communication unit 120 of the UE 100 receives the message including the configuration information from the P cell 210P (first network 200A). The message may be a response to the restriction information.

[0100] The configuration information may include information indicating at least one of the configurations (specifically, reduction configurations) of the secondary cell (or secondary cell group), the frequency band, and the MIMO layer.

[0101] The control unit 130 (e.g., the RRC processing unit 131) restricts communication capabilities based on the configuration information. The control unit 130 may reduce or release secondary cells or secondary cell groups based on the configuration information. The control unit 130 may reduce frequency bands based on the configuration information. The control unit 130 may reduce the number of MIMO layers based on the configuration information.

[0102] The control unit 130 executes control to continue communication with the first network 200A via some of the multiple transceivers (e.g., the first transceiver 121) using the communication capabilities of the UE 100 that have not been temporarily limited. The control unit 130 may perform communication with the first network 200A via the first transceiver 121 based on an RRC setting based on setting information received from the first network 200A. The control unit 130 may, for example, maintain the RRC setting used for communication with the first network 200A via the first transceiver 121. The control unit 130 may release at least a portion of the RRC setting used for communication with the first network 200A via the second transceiver 122, and start communication with the first network 200A via the first transceiver 121 based on the remaining RRC setting.

[0103] Meanwhile, the control unit 130 executes control to terminate communication with the first network 200A via some of the multiple transceivers (e.g., the second transceiver 122). The control unit 130 may, for example, release the RRC setting used for communication with the first network 200A via the second transceiver 122. The control unit 130 executes control to restrict communication capacity and start connection with the second network 200B.

[0104] Step S108: Based on the execution of the restriction on the communication capacity, the RRC processing unit 131 provides a second NW switching preparation completion notification to the NAS processing unit 132. The NAS processing unit 132 receives the second NW switching preparation completion notification from the RRC processing unit 131. The second NW switching preparation completion notification may be a notification indicating that preparation for establishing an RRC connection with the second network 200B has been completed.

[0105] Step S109: Based on the reception of the second NW switching completion notification, the NAS processing unit 132 provides a second NW connection instruction to the RRC processing unit 131. The RRC processing unit 131 receives the second NW connection instruction from the NAS processing unit 132. The second NW connection instruction may be an instruction to establish an RRC connection with the second network 200B.

[0106] Step S110: The RRC processing unit 131 performs processing for starting an RRC connection with the base station 210B based on the second NW connection instruction. The RRC processing unit 131 may perform, for example, an RRC setup procedure (Setup) for establishing an RRC connection or an RRC re-establishment procedure (Reestablishment) for re-establishing an RRC connection. The RRC processing unit 131 may also perform an RRC resume procedure (Resume) for resuming a suspended RRC connection. In this operation example, a case in which the RRC processing unit 131 performs an RRC setup procedure will be described as an example.

[0107] The RRC processing unit 131 controls transmission of an RRC setup request message to the second network 200B (specifically, the base station 210B). The communication unit 120 transmits the RRC setup request message to the second network 200B. The radio communication unit 212 of the base station 210B receives the RRC setup request message from the UE 100.

[0108] Step S111: The radio communication unit 212 of the base station 210B transmits an RRC setup message used to establish SRB (Signaling Radio Bearer) 1 to the UE 100. The communication unit 120 of the UE 100 receives the RRC setup message from the base station 210B (second network 200B). The control unit 130 of the UE 100 performs processing to establish an RRC connection (for example, SRB1) based on the RRC setup message. After performing the processing to establish the RRC connection, the control unit 130 performs the processing of step S114.

[0109] Step S112: The RRC processing unit 131 controls transmission of an RRC setup complete message to the second network 200B (specifically, the base station 210B). The communication unit 120 transmits the RRC setup complete message to the second network 200B. The radio communication unit 212 of the base station 210B receives the RRC setup complete message from the UE 100.

[0110] When the control unit 130 (RRC processing unit 131) does not transmit restriction information to the second network 200B in the RRC setup procedure, the control unit 130 (RRC processing unit 131) may transmit notification information to the second network 200B in the RRC setup procedure, notifying the second network 200B that communication capability is temporarily restricted. When the control unit 130 plans to transmit restriction information, the control unit 130 may transmit notification information to the second network 200B.

[0111] As shown at E21 in Fig. 11 , the control unit 130 may, for example, include the notification information in an RRC setup complete message. The control unit 130 may include the notification information in the RRC setup complete message when the control unit 130 is communicating with the first network 200A using at least one transceiver unit (e.g., the first transceiver unit 121) of the multiple transceivers and is communicating with the second network 200B using a transceiver unit (e.g., the second transceiver unit 122) different from the at least one transceiver unit of the multiple transceivers. Note that the control unit 130 may, for example, include the notification information in an RRC setup request message (see E21 in Fig. 11 ).

[0112] The notification information may be, for example, information indicating a change in the communication capability of the UE 100. The notification information may be, for example, information indicating that there is a change in the communication capability of the UE 100 or information indicating that a change in the communication capability of the UE 100 is desired (or recommended (prefer)). The notification information may be, for example, information indicating that the communication capability of the UE 100 is temporarily restricted, information indicating that a restriction on the communication capability of the UE 100 is temporarily lifted, and / or information indicating that a temporary restriction on the communication capability of the UE 100 is changed. The notification information may be, for example, information indicating that the UE radio access capability is changed or updated.

[0113] The notification information may be, for example, flag information indicating that the communication capability is temporarily restricted. As shown in FIG. 11 , when the notification information (for example, "musimCapabilityReduced (musimCapabilityReduced-r18)") includes predetermined information (for example, "true"), it may indicate that the communication capability is temporarily restricted. When the field of the notification information is empty or the notification information indicates information other than the predetermined information, the notification information may indicate that the communication capability is not temporarily restricted.

[0114] The communication unit 120 may transmit notification information to the second network 200B when it is communicating with the first network 200A using at least one of the multiple transmission / reception units (e.g., the first transmission / reception unit 121) and communicating with the second network 200B using a transmission / reception unit (e.g., the second transmission / reception unit 122) different from at least one of the multiple transmission / reception units.

[0115] As will be described later, the communication unit 120 can transmit the restriction information to the second network 200B after transmitting the notification information. The communication unit 120 may transmit the restriction information to the second network 200B within a predetermined time after transmitting the notification information.

[0116] The control unit 130 may have a timer for timing the predetermined time. The control unit 130 may start the timer based on the transmission of notification information (a message including the notification information). The predetermined time may be, for example, a predetermined value. The communication unit 120 may receive timer information indicating the predetermined time from the second network 200B. The control unit 130 may set the predetermined time in the timer based on the timer information.

[0117] If the timer expires before the restriction information is transmitted, i.e., if the restriction information cannot be transmitted to the second network 200B within a predetermined time, the control unit 130 may transmit the notification information to the second network 200B again. Alternatively, if the timer expires before the restriction information is transmitted, the control unit 130 may terminate the process for transmitting the restriction information to the second network 200B.

[0118] Note that, when the UE 100 executes a procedure for performing processing for starting an RRC connection with the base station 210B other than the RRC setup procedure (e.g., an RRC re-establishment procedure, an RRC resume procedure, etc.), the UE 100 may transmit notification information to the second network 200B, similar to the above-described RRC setup procedure. For example, an RRC re-establishment request message, an RRC re-establishment complete message (see E22 in FIG. 11 ), an RRC resume request message, an RRC resume request 1 message, and / or an RRC resume complete message (see E23 in FIG. 11 ) may be used as a message including the notification information.

[0119] The control unit 214 of the base station 210B may suspend configuring the settings of the UE 100 based on the reception of the notification information. The control unit 214 may suspend configuring the settings of the UE 100 until it receives the restriction information. The control unit 214 may suspend configuring the settings of the UE 100 until a predetermined time has elapsed since the reception of the notification information. When timer information indicating a predetermined time has been transmitted to the UE 100, the control unit 214 may suspend configuring the settings of the UE 100 until the predetermined time indicated by the timer information has elapsed. Note that when the predetermined time has elapsed, the control unit 214 may start (resume) configuring the settings of the UE 100 if it had suspended configuring the settings of the UE 100. When the control unit 214 has received notification information from the UE 100 but has not received restriction information by the expiration of the timer, it may configure the settings of the UE 100 based on the UE capability information message.

[0120] Step S113: The wireless communication unit 212 of the base station 210B transmits a capability query message (for example, a UE capability query message) to the UE 100 to request capability information regarding communication capabilities used for communication in the second network 200B. The communication unit 120 of the UE 100 receives the capability query message from the second network 200B (base station 210B). The UE capability query message is a message used to request UE radio access capabilities for NR (NR Radio Access) as well as for other RATs (Radio Access Technologies).

[0121] Step S114: The RRC processing unit 131 controls transmission of a capability information message (e.g., a UE capability information message) for transferring capability information to the second network 200B. The communication unit 120 transmits the capability information message to the second network 200B. The wireless communication unit 212 of the base station 210B receives the capability information message from the UE 100. The UE capability information message is a message used to transfer UE access capabilities requested by the network. The control unit 130 may include information indicating the normal communication capabilities (unrestricted communication capabilities) of the UE 100 in the capability information message.

[0122] In addition, even if the control unit 214 of the base station 210B receives a capability information message, if notification information has been received, the control unit 214 may postpone configuring the settings of the UE 100 until a predetermined time has elapsed.

[0123] Step S115: The RRC processing unit 131 controls transmission of restriction information to the second network 200B to temporarily restrict the communication capability of the UE 100 used for communication with the second network 200B. The communication unit 120 transmits the restriction information to the second network 200B. The communication unit 120 may transmit a message including the restriction information to the P cell 210P. The wireless communication unit 212 of the base station 210B receives the restriction information from the UE 100 in the P cell 210P.

[0124] The message including the restriction information may be the same message as in step S105. Thus, the restriction information may be included in, for example, a request message used for a request regarding the RRC connection, a completion message used to confirm that the procedure regarding the RRC connection has been successfully completed, a UE information response message for transferring the requested information to the second network 200B, and / or a UE assistance information message.

[0125] The restriction information is used to temporarily restrict the communication capability of the UE 100 used for communication with the second network 200B. The restriction information may be the same information as in step S105.

[0126] For example, the controller 130 may include restriction information in the MUSIM auxiliary information element. The controller 130 may also include at least one of information for restricting secondary cells, information for restricting frequency bands, and information for restricting multiple-input multiple-output (MIMO) layers as restriction information in the MUSIM auxiliary information element. The controller 130 may also include information indicating the number of transceivers available for communication with the second network 200B as restriction information in the MUSIM auxiliary information element. The controller 130 may also include flag information for deactivating or releasing a secondary cell as restriction information in the MUSIM auxiliary information element. The controller 130 may also include an overheating auxiliary information element, which is transmitted based on detection of internal overheating, as restriction information, regardless of whether internal overheating has been detected.

[0127] The communication unit 120 may transmit restriction information to the second network 200B when it is communicating with the first network 200A using at least one of the multiple transmission / reception units (e.g., the first transmission / reception unit 121) and communicating with the second network 200B using a transmission / reception unit (e.g., the second transmission / reception unit 122) different from at least one of the multiple transmission / reception units.

[0128] The control unit 214 of the base station 210B may determine, based on the restriction information, whether to temporarily restrict the communication capability of the UE 100 used for communication with the second network 200B. The control unit 214 may execute the same process as the base station 210A, based on the restriction information. Note that, if the control unit 214 of the base station 210B has suspended configuring the settings of the UE 100, it may start (resume) configuring the settings of the UE 100.

[0129] Step S116: The radio communication unit 212 of the base station 210B may transmit to the UE 100 a message (for example, an RRC reconfiguration message) including configuration information for temporarily restricting the communication capability of the UE 100. The communication unit 120 of the UE 100 receives the message including the configuration information from the second network 200B (base station 210B).

[0130] Thereafter, the UE 100 communicates with the second network 200B. For example, the control unit 130 of the UE 100 may start processing for performing communication corresponding to the paging message in the second network 200B. The control unit 130 of the UE 100 may control the communication with the second network 200B via the second transceiver unit 122. Note that the control unit 130 may continue to control the communication with the first network 200A via the first transceiver unit 121.

[0131] As described above, the control unit 130 temporarily restricts the communication capability of the UE 100 used for communication with the second network 200B when communicating with the first network 200A. The communication unit 120 transmits restriction information for temporarily restricting the communication capability of the UE 100 used for communication with the second network 200B to the second network 200B. This allows the second network 200B to recognize the temporary restriction on the communication capability of the UE 100 based on the restriction information. This makes it easier to appropriately synchronize the UE 100 and the second network 200B regarding the temporary restriction on the communication capability.

[0132] Furthermore, the restriction information may be included in a request message used for a request regarding the RRC connection. This allows the UE 100 to send the restriction information to the network when making a request regarding the RRC connection, thereby eliminating the need to transmit a new message just for notifying the restriction information, and enabling effective use of radio resources.

[0133] Furthermore, the restriction information may be included in a completion message used to confirm that the procedure related to the RRC connection has been completed successfully. This allows the UE 100 to send the restriction information to the network when notifying that the procedure related to the RRC connection has been completed successfully. Therefore, it is not necessary to transmit a new message just for notifying the restriction information, and radio resources can be used effectively.

[0134] Furthermore, the restriction information may be included in a UE information response message for transferring the requested information to the second network 200 B. This allows the UE 100 to send a capability change notification to the network when responding to the UE information request message, thereby eliminating the need to send a new message just for notifying the capability change notification and enabling effective use of radio resources.

[0135] Furthermore, the restriction information may be included in a UE assistance information message, which allows the UE 100 to voluntarily transmit the restriction information to the second network 200B.

[0136] Furthermore, the restriction information may be included in a MUSIM auxiliary information element, so that the second network 200B can know that the UE 100 is transmitting the restriction information for MUSIM operation (e.g., communication with the first network 200A).

[0137] Furthermore, the control unit 130 may include at least one of information for restricting a secondary cell, information for restricting a frequency band, and information for restricting a layer of multiple-input multiple-output (MIMO) in the MUSIM auxiliary information element as restriction information. This allows the UE 100 to notify the second network 200B that it recommends restricting any one of the secondary cell, the frequency band, and the MIMO layer.

[0138] Furthermore, the control unit 130 may include, as limitation information, information indicating the number of transceivers available for communication with the second network 200B in the MUSIM auxiliary information element. This allows the UE 100 to notify the first network 200A of the transceivers available for communication with the second network 200B (that the transceivers are recommended).

[0139] Furthermore, the control unit 130 may include flag information for deactivating or releasing the secondary cell as restriction information in the MUSIM auxiliary information element. This allows the UE 100 to notify the second network 200B that the UE 100 is (recommending) to deactivate or release the secondary cell. In addition, the flag information has a small amount of information (e.g., 1 bit), which can save radio resources.

[0140] Furthermore, the control unit 130 may include the overheating auxiliary information element, which is transmitted based on the detection of internal overheating, in the MUSIM auxiliary information element as restriction information, regardless of whether internal overheating has been detected. This eliminates the need to newly define an information element that includes restriction information, thereby reducing the impact on specifications.

[0141] Furthermore, the communication unit 120 may transmit notification information to the second network 200B notifying that the communication capability is temporarily restricted. After transmitting the notification information, the communication unit 120 may transmit restriction information to the second network 200B. This allows the second network 200B to know that the communication capability is temporarily restricted based on the notification information. Thereafter, the second network 200B becomes able to recognize the temporary restriction on the communication capability of the UE 100 based on the restriction information. Therefore, it is possible to facilitate appropriate synchronization between the UE 100 and the second network 200B regarding the temporary restriction on the communication capability.

[0142] Furthermore, the communication unit 120 may transmit the restriction information to the second network 200B within a predetermined time after transmitting the notification information. This allows the second network 200B to recognize the temporary restriction on the communication capability of the UE 100 before the predetermined time has elapsed after learning that the communication capability is temporarily restricted.

[0143] Furthermore, the communication unit 120 may receive timer information indicating the predetermined time from the second network 200 B. The second network 200 B can flexibly control the predetermined time.

[0144] (2) Second Operation Example The second operation example will be described, mainly focusing on differences from the above-described operation example, with reference to Fig. 12 and Fig. 13. In the second operation example, a case will be described in which the UE 100 transmits information for releasing or changing a temporary restriction on communication capability to the second network 200B.

[0145] In the second operation example, the UE 100 is in an RRC connected state in the first network 200A. The UE 100 communicates with the first network 200A. Specifically, the UE 100 communicates with the P cell 210P (or MCG). On the other hand, the UE 100 does not communicate with the S cell 210S (or SCG).

[0146] Furthermore, the UE 100 is in an RRC connected state in the second network 200B. The UE 100 is communicating with the second network 200B. Specifically, the UE 100 is communicating with the P cell 210P (or MCG). On the other hand, the UE 100 is not communicating with the S cell 210S (or SCG). The UE 100 may use the first transceiver 121 for communication with the first network 200A and the second transceiver 122 for communication with the second network 200B.

[0147] As in the first operation example, the control unit 130 of the UE 100 temporarily restricts the communication capability of the UE 100 used for communication with the first network 200A, in order to communicate with the second network 200B. Also, in order to communicate with the first network 200A, the control unit 130 temporarily restricts the communication capability of the UE 100 used for communication with the second network 200B.

[0148] Step S201: The UE 100 terminates communication with the first network 200A.

[0149] Step S202: The radio communication unit 212 of the base station 210A transmits an RRC release message to the UE 100. The communication unit 120 of the UE 100 receives the RRC release message from the base station 210A. Based on the reception of the RRC release message, the control unit 130 of the UE 100 transitions from the RRC connected state to the RRC idle state or the RRC inactive state in the first network 200A. As a result, the UE 100 may release the RRC connection in the first network 200A.

[0150] Step S203: The control unit 130 (e.g., the RRC processing unit 131) may provide a release completion notification indicating the completion of release of the RRC connection to the NAS processing unit 132. In response to receiving the release completion notification, the control unit 130 (e.g., the NAS processing unit 132 or a processing unit in a layer higher than the NAS layer) may determine whether to release the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B. Furthermore, the control unit 130 may determine whether to change the temporary restriction on the communication capability.

[0151] The control unit 130 may determine to release or change the temporary restriction based on, for example, a transition to an RRC idle state in the first network 200A. The control unit 130 may determine not to release or change the temporary restriction based on, for example, a transition to an RRC inactive state in the first network 200A.

[0152] The control unit 130 may determine whether to lift the temporary restriction or whether to change the temporary restriction based on the service provided from the second network 200B. The control unit 130 may determine to lift the temporary restriction when the service provided from the second network 200B is a voice service. The control unit 130 may determine not to lift the temporary restriction when the service provided from the second network 200B is a service other than a voice service. In this case, the control unit 130 may determine to change the temporary restriction.

[0153] The control unit 130 may determine whether to lift the temporary restriction or whether to change the temporary restriction based on, for example, an input from the user. The control unit 130 may determine to lift the temporary restriction when the user's input prioritizes communication with the second network 200B over communication with the first network 200A. The control unit 130 may determine not to lift the temporary restriction when the user's input does not prioritize communication with the second network 200B over communication with the first network 200A.

[0154] The determination may be made in the NAS processing unit 132, or may be made in a layer higher than the NAS processing unit. When the determination is made in the higher layer, the determination result may be provided to the NAS processing unit 132.

[0155] If it is determined that the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B is to be lifted or changed, the NAS processing unit 132 executes the process of step S204. On the other hand, if it is determined that the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B is not to be lifted or changed, the control unit 130 may end the process of this operation without executing the process of step S204.

[0156] Step S204: As shown in Fig. 12, when it is determined to release the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B, the NAS processing unit 132 provides a capability restriction release instruction to the RRC processing unit 131. The RRC processing unit 131 receives the capability restriction release instruction from the NAS processing unit 132. The capability restriction release instruction may be for issuing an instruction to transmit restriction release information, which will be described later. The capability restriction release instruction may indicate the content of the restriction release information.

[0157] When it is determined that the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B is to be changed, the NAS processing unit 132 provides a capacity restriction change instruction to the RRC processing unit 131. The RRC processing unit 131 receives the capacity restriction change instruction from the NAS processing unit 132. The capacity restriction change instruction may be for instructing transmission of restriction change information, which will be described later. The capacity restriction change instruction may indicate the content of the restriction change information.

[0158] Step S205: Based on the capability restriction release instruction, the control unit 130 (RRC processing unit 131) controls transmission of restriction release information to the second network 200B for communication with the second network 200B. The communication unit 120 transmits the restriction release information to the second network 200B for communication with the second network 200B. Specifically, the communication unit 120 transmits the restriction release information to the P cell 210P. The communication unit 120 may transmit a message including the restriction release information to the P cell 210P. The wireless communication unit 212 of the base station 210B receives the restriction release information from the UE 100 in the P cell 210P. The restriction release information is used to release the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B.

[0159] The control unit 130 (e.g., RRC processing unit 131) may include restriction removal information (e.g., MUSIM-ReducedCapability) in a MUSIM auxiliary information element used to provide the MUSIM auxiliary information. The communication unit 120 may transmit the MUSIM auxiliary information including the restriction removal information to the second network 200B. The communication unit 120 may transmit a UE auxiliary information message including the MUSIM auxiliary information including the restriction removal information to the second network 200B.

[0160] The control unit 130 may set a null value to at least one of the information for restricting a secondary cell, the information for restricting a frequency band, and the information for restricting a multiple-input multiple-output (MIMO) layer. The control unit 130 may include the information set to a null value in a MUSIM auxiliary information element as restriction removal information. The null value may be a value such as zero or a null value. Alternatively, the control unit 130 may not include any of the information for restricting a secondary cell, the information for restricting a frequency band, and the information for restricting a multiple-input multiple-output (MIMO) layer in the MUSIM auxiliary information element. In this case, a MUSIM auxiliary information element that does not include information for temporarily restricting communication capability may be considered as restriction removal information.

[0161] The information for restricting secondary cells, the information for restricting frequency bands, and the information for restricting layers of multiple-input multiple-output (MIMO) are the same as those in the first operation example.

[0162] The control unit 130 may include, as restriction lift information, information indicating zero as the number of transceivers usable for communication with the second network 200B in the MUSIM auxiliary information element. The information may indicate the maximum number of transceivers usable for communication with the second network 200B. The control unit 130 may also include, as restriction lift information, at least one of information indicating zero as the number (or maximum number) of transmitters (e.g., transmitters) usable for communication with the second network 200B and information indicating zero as the number (or maximum number) of receivers (e.g., receivers) usable for communication with the second network 200B in the MUSIM auxiliary information element. The control unit 130 may set a null value to the information indicating the number of transceivers, transmitters, or receivers.

[0163] As shown in E31 of FIG. 13 , the control unit 130 may include flag information for activating a secondary cell (for example, which may be referred to as "activateSCG") in the MUSIM auxiliary information element as restriction release information. The flag information may be, for example, information indicated by 1 bit. For example, when "true" is set in the flag information, this may indicate activation of a secondary cell or activation of a secondary cell group. When the UE 100 was performing dual connectivity before temporarily restricting the communication capability, the control unit 130 may include the flag information in the MUSIM auxiliary information element as restriction release information.

[0164] Furthermore, the control unit 130 may not include the specified information to be set in the overheating auxiliary information element when providing the overheating auxiliary indication. The control unit 130 typically does not include the specified information in the overheating auxiliary information element based on the fact that internal overheating is no longer detected in the UE 100 (e.g., the UE 100 no longer experiences an overheating condition). However, the control unit 130 may not include the specified information in the overheating auxiliary information element regardless of whether internal overheating is no longer detected in the UE 100. Thus, the communication unit 120 may transmit an overheating auxiliary information element that does not include the specified information to the second network 200B as restriction release information for communication with the second network 200B, regardless of whether internal overheating is no longer detected.

[0165] 13, the control unit 130 may include information (e.g., releaseRedCap) indicating temporary release of the restriction on the communication capability of the UE 100 used for communication with the second network 200B in the MUSIM auxiliary information element as restriction release information. For example, when "true" is set in the information, it may indicate temporary release of the restriction on the communication capability.

[0166] Furthermore, the control unit 130 may include information for activating the secondary cell as restriction lift information in the UE assistance information message. Here, the control unit 130 may include the restriction lift information in an information element different from the MUSIM assistance information element among information elements included in the UE assistance information message. For example, the control unit 130 may include specified information (specifically, scg-ActivationPreference) to be included in the UE assistance information based on recommending a secondary cell group to be activated. Therefore, the communication unit 120 may transmit the information for activating the secondary cell to the second network 200B as restriction lift information.

[0167] Furthermore, the control unit 130 (RRC processing unit 131) may perform control to transmit restriction change information to the second network 200B based on the capability restriction change instruction. The communication unit 120 may transmit the restriction change information to the second network 200B. Specifically, the communication unit 120 may transmit the restriction change information to the P cell 210P. The communication unit 120 may transmit a message including the restriction change information to the P cell 210P. The wireless communication unit 212 of the base station 210B receives the restriction change information from the UE 100 in the P cell 210P. The restriction change information is used to change a temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B for communication with the first network 200A.

[0168] The control unit 130 (e.g., RRC processing unit 131) may include restriction change information (e.g., MUSIM-ReducedCapability) in a MUSIM auxiliary information element used to provide MUSIM auxiliary information. The communication unit 120 may transmit the MUSIM auxiliary information including the restriction change information to the second network 200B. The communication unit 120 may transmit a UE auxiliary information message including the MUSIM auxiliary information including the restriction change information to the second network 200B.

[0169] The control unit 130 may include at least one of information for restricting secondary cells, information for restricting frequency bands, and information for restricting multiple-input multiple-output (MIMO) layers as restriction change information in the MUSIM auxiliary information element. The control unit 130 may include information indicating restrictions after changing the communication capability as restriction change information in the MUSIM auxiliary information element. Note that the information for restricting secondary cells, information for restricting frequency bands, and information for restricting multiple-input multiple-output (MIMO) layers is the same information as in the first operation example.

[0170] The control unit 130 may include, as restriction change information, information indicating the number of transceiver units (e.g., transceivers) available for communication with the second network 200B (which may be referred to as nrofRxBranches, for example), in the MUSIM auxiliary information element. Furthermore, the control unit 130 may include, as restriction change information, at least one of information indicating the number (or maximum number) of transmitters (e.g., transmitters) available for communication with the second network 200B and information indicating the number (or maximum number) of receivers (e.g., receivers) available for communication with the second network 200B, in the MUSIM auxiliary information element.

[0171] Furthermore, the control unit 130 may include specified information to be set in the overheating auxiliary information element when providing the overheating auxiliary indication. The control unit 130 may typically include the specified information in the overheating auxiliary information element based on whether internal overheating has been detected in the UE 100. However, the control unit 130 may include the specified information in the overheating auxiliary information element regardless of whether internal overheating has been detected in the UE 100. Therefore, the communication unit 120 may transmit the overheating auxiliary information element to the second network 200B as restriction change information for communication with the first network 200A, regardless of whether internal overheating has been detected.

[0172] Furthermore, the control unit 130 may include gap recommendation information (e.g., musim-GapPreferenceList, MUSIM-GapPrefInfo, etc.) indicating gaps for MUSIM operation that the UE 100 recommends being set in the MUSIM auxiliary information element together with the restriction release information or restriction change information. Furthermore, the control unit 130 may include the MUSIM auxiliary information element including the gap recommendation information in a UE auxiliary information message including the restriction release information or restriction change information. The control unit 130 may include the gap recommendation information in the MUSIM auxiliary information element based on the end of communication with the first network 200A. Note that the control unit 130 may include the MUSIM auxiliary information element including the gap recommendation information in a UE auxiliary information message including the restriction release information or restriction change information.

[0173] The gap recommendation information may include at least one of information indicating the length of the MUSIM gap length recommended by UE100 (e.g., musim-GapLength), information indicating the gap offset of the MUSIM gap recommended by UE100 (e.g., musim-GapOffset), information indicating the gap start position of the non-periodic MUSIM gap recommended by UE100 while maintaining the RRC connected state (e.g., musim-PrefStarting-SFN-AndSubframex), and information indicating the gap reception period and gap offset of the periodic MUSIM gap recommended by UE100 while maintaining the RRC connected state (e.g., musim-GapRepetitionAndOffsetPeriod).

[0174] The communication unit 120 may have a plurality of transceivers. When the UE 100 is communicating with the second network 200B using at least one of the plurality of transceivers and has terminated communication with the first network 200A using a transceiver different from the at least one of the plurality of transceivers, the communication unit 120 may transmit restriction release information or restriction change information to the second network 200B.

[0175] The control unit 214 of the base station 210B may determine whether to lift or change the temporary restriction on the communication capability of the UE 100 used for communication with the second network 200B, based on the restriction lift information or the restriction change information. When the control unit 214 of the base station 210B determines to lift or change the temporary restriction on the communication capability of the UE 100, the control unit 214 may execute the process of step S106. When the control unit 214 of the base station 210B determines not to lift or change the temporary restriction on the communication capability of the UE 100, the control unit 214 may end the process.

[0176] Step S206: The network communication unit 213 of the base station 210B that manages the P cell 210P may transmit a scheduling start instruction to another base station 210B that manages the S cell 210S. When the base station 210B manages the P cell 210P and the S cell 210S, the base station 210B may send the scheduling start instruction from the entity that manages the P cell 210P to the entity that manages the S cell 210S within the control unit 214.

[0177] The scheduling start instruction may be for starting scheduling assigned to the UE 100, or may be for starting part of scheduling assigned to the UE 100. The scheduling start instruction may include at least part of the information of the restriction change information.

[0178] Based on the scheduling start instruction, the control unit 214 of the base station 210B that manages the S cell 210S may release the temporary restriction on the communication capability of the UE 100. The network communication unit 213 of the base station 210B may transmit a response message indicating that scheduling start will be executed to the base station 210B that manages the P cell 210P. Based on the reception of the response message, the control unit 214 of the base station 210B that manages the P cell 210P may execute the process of step S207.

[0179] Step S207: In the P cell 210P, the radio communication unit 212 of the base station 210B transmits to the UE 100 a message (for example, an RRC reconfiguration message) including configuration information for releasing or changing the temporary restriction on the communication capability of the UE 100. The communication unit 120 of the UE 100 receives the message including the configuration information from the P cell 210P (second network 200B). The message may be a response to the restriction release information or the restriction change information.

[0180] The setting information may include information indicating at least one setting of a secondary cell (or a secondary cell group), a frequency band, and a MIMO layer. The setting information may include information for setting a MUSIM gap. The information may indicate a MUSIM gap setting recommended by the UE 100, or may indicate a different MUSIM gap setting.

[0181] Step S208: The UE 100 starts communication with the S cell 210S (or SCG) while maintaining communication with the P cell 210P (or MCG).

[0182] The control unit 130 (e.g., the RRC processing unit 131) removes or changes the restriction on communication capability based on the setting information. The control unit 130 may set a secondary cell or a secondary cell group based on the setting information. The control unit 130 may set a frequency band based on the setting information. The control unit 130 may set the number of MIMO layers based on the setting information.

[0183] Based on the RRC setting based on the setting information received from the second network 200B, the control unit 130 may communicate with the second network 200B via the first transceiver unit 121, in addition to communicating with the second network 200B via the second transceiver unit 122. The control unit 130 may, for example, communicate with the P cell 210P (or MSG) via the second transceiver unit 122, and may also communicate with the S cell 210S (or SCG) via the first transceiver unit 121.

[0184] The setting information may include information for setting a MUSIM gap. As an example of a MUSIM operation, the controller 130 may monitor paging in the first network 200A or attempt to receive a system information block during the set MUSIM gap.

[0185] As described above, the communication unit 120 may transmit restriction release information or restriction change information for releasing or changing the temporary restriction on the communication capability to the second network 200B. This allows the second network 200B to recognize the temporary restriction on the communication capability of the UE 100 based on the restriction release information or the restriction change information. This makes it easier to appropriately synchronize the temporary restriction on the communication capability between the UE 100 and the second network 200B.

[0186] Furthermore, when the UE 100 is communicating with the second network 200B using at least one of the plurality of transceivers, and has terminated communication with the first network 200A using a transceiver different from the at least one of the plurality of transceivers, the communication unit may transmit restriction release information or restriction change information to the second network 200B. This allows the UE 100 to use the transceiver that was used for communication with the first network 200A for communication with the second network 200B.

[0187] [Other Embodiments] In the above-described embodiment, the case where the UE 100 has two transceivers is described, but this is not limited thereto. The UE 100 may have a plurality of transceivers. For example, the UE 100 may have three or more transceivers.

[0188] In the above-described embodiment, the UE 100 starts the procedure for transmitting the restriction information in response to paging from the first network 200A, but this is not limiting. The UE 100 may start the procedure in response to, for example, an input from a user.

[0189] The operation sequences (and operation flows) in the above-described embodiments do not necessarily have to be executed in chronological order according to the order depicted in the flow diagrams or sequence diagrams. For example, steps in the operations may be executed in an order different from that depicted in the flow diagrams or sequence diagrams, or may be executed in parallel. Some steps in the operations may be deleted, or additional steps may be added to the processing. The operation sequences (and operation flows) in the above-described embodiments may be executed independently, or two or more operation sequences (and operation flows) may be executed in combination. For example, some steps in one operation flow may be added to another operation flow, or some steps in one operation flow may be replaced with some steps in another operation flow.

[0190] In the above-described embodiment, an NR-based mobile communication system has been described as an example of the mobile communication system 1. However, the mobile communication system 1 is not limited to this example. The mobile communication system 1 may be a system compliant with the TS of either LTE (Long Term Evolution) or another generation system (e.g., 6th generation) of the 3GPP standard. The base station 210 may be an eNB that provides E-UTRA user plane and control plane protocol termination toward the UE 100 in LTE. The mobile communication system 1 may be a system compliant with the TS of a standard other than the 3GPP standard. The base station 210 may be an IAB (Integrated Access and Backhaul) donor or an IAB node.

[0191] A program may be provided that causes a computer to execute each process performed by the UE 100 or the base station 210. The program may be recorded on a computer-readable medium. Using the computer-readable medium, the program can be installed on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM (Compact Disk Read Only Memory) or a DVD-ROM (Digital Versatile Disc Read Only Memory). Furthermore, circuits that execute each process performed by the UE 100 or the base station 210 may be integrated, and at least a part of the UE 100 or the base station 210 may be configured as a semiconductor integrated circuit (chip set, SoC (System On Chip)).

[0192] In the above-described embodiments, "transmit" may mean performing processing at least one layer in a protocol stack used for transmission, or may mean physically transmitting a signal wirelessly or via a wired connection. Alternatively, "transmit" may mean a combination of performing processing at least one layer and physically transmitting a signal wirelessly or via a wired connection. Similarly, "receive" may mean performing processing at least one layer in a protocol stack used for reception, or may mean physically receiving a signal wirelessly or via a wired connection. Alternatively, "receive" may mean a combination of processing at least one layer and physically receiving a signal wirelessly or via a wired connection. Similarly, "obtain / acquire" may mean obtaining information from stored information, obtaining information from information received from another node, or obtaining information by generating the information. Similarly, the terms "based on" and "depending on / in response to" do not mean "based only on" or "depending only on," unless expressly stated otherwise. The term "based on" means both "based only on" and "based at least in part on." Similarly, the term "depending on" means both "depending only on" and "depending at least in part on." Similarly, "include" and "comprise" do not mean including only the listed items, but may mean including only the listed items or may include additional items in addition to the listed items. Similarly, in this disclosure, "or" does not mean an exclusive or, but rather a logical or. Furthermore, any reference to elements using designations such as "first," "second," etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements.Thus, a reference to a first and a second element does not imply that only two elements may be employed therein or that the first element must precede the second element in some way. In this disclosure, where articles are added by translation, such as a, an, and the in English, these articles shall include the plural unless the context clearly indicates otherwise.

[0193] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

[0194] (Additional Notes) Additional notes will be given regarding the features of the above-described embodiment.

[0195] (Supplementary Note 1) A communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, comprising: a control unit that temporarily restricts a communication capability of the communication device used for communication with a second network when communicating with a first network; and a communication unit that transmits restriction information for temporarily restricting the communication capability to the second network.

[0196] (Supplementary Note 2) The communication device according to Supplementary Note 1, wherein the restriction information is included in a request message used for a request regarding a Radio Resource Control (RRC) connection.

[0197] (Supplementary Note 3) The communication device according to Supplementary Note 1 or 2, wherein the restriction information is included in a completion message used to confirm successful completion of a procedure related to a radio resource control (RRC) connection.

[0198] (Supplementary Note 4) The communication device according to any one of Supplementary Notes 1 to 3, wherein the restriction information is included in a UE information response message for transferring the requested information to the second network.

[0199] (Supplementary Note 5) The communication device according to any one of Supplementary Notes 1 to 4, wherein the restriction information is included in a UE assistance information message used for indicating UE assistance information.

[0200] (Supplementary Note 6) The communications device of Supplementary Note 5, wherein the restriction information is included in a Multiple Universal Subscriber Identity Module (MUSIM) auxiliary information element used to provide MUSIM auxiliary information.

[0201] (Supplementary Note 7) The communication device according to Supplementary Note 6, wherein the control unit includes at least one of information for restricting a secondary cell, information for restricting a frequency band, and information for restricting a layer of multiple-input multiple-output (MIMO) in the MUSIM auxiliary information element as the restriction information.

[0202] (Supplementary Note 8) The communication device according to Supplementary Note 6 or 7, wherein the control unit includes information indicating the number of transceivers available for communication with the second network in the MUSIM auxiliary information element as the restriction information.

[0203] (Supplementary Note 9) The communication device according to any one of Supplementary Notes 6 to 8, wherein the control unit includes flag information for deactivating or releasing a secondary cell as the restriction information in the MUSIM auxiliary information element.

[0204] (Supplementary Note 10) The communication device according to any one of Supplementary Notes 6 to 9, wherein the control unit includes an overheating auxiliary information element, which is transmitted based on the detection of internal overheating, in the MUSIM auxiliary information element as the restriction information, regardless of whether the internal overheating is detected or not.

[0205] (Supplementary Note 11) The communication device according to any one of Supplementary Notes 1 to 10, wherein the communication unit transmits information for canceling or changing the temporary restriction on the communication capability to the second network.

[0206] (Supplementary Note 12) The communication device described in Supplementary Note 11, wherein the communication unit has a plurality of transceivers, and when the communication device is communicating with the second network using at least one transceiver of the plurality of transceivers and has terminated communication with the first network using a transceiver of the plurality of transceivers different from the at least one transceiver of the plurality of transceivers, the communication unit transmits information for the release or change to the second network.

[0207] (Supplementary Note 13) The communication device according to any one of Supplementary Notes 1 to 12, wherein the communication unit transmits notification information to the second network notifying that the communication capability is temporarily restricted, and the communication unit transmits the restriction information to the second network after transmitting the notification information.

[0208] (Supplementary Note 14) The communication device according to Supplementary Note 13, wherein the communication unit transmits the restriction information to the second network within a predetermined time after transmitting the notification information.

[0209] (Supplementary Note 15) The communication device according to Supplementary Note 14, wherein the communication unit receives timer information indicating the predetermined time from the second network.

[0210] (Supplementary Note 16) A base station of a network in a mobile communication system having a communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, the base station comprising: a communication unit that receives, from the communication device communicating with another network, restriction information for temporarily restricting the communication capability of the communication device used for communication with the network.

[0211] (Supplementary Note 17) A communication method executed by a communication device capable of communicating with a plurality of networks using a plurality of subscriber identity modules, comprising: a step of temporarily restricting a communication capability of the communication device used for communication with a second network when communicating with a first network; and a step of transmitting restriction information for temporarily restricting the communication capability to the second network.

Claims

1. A communication device (100) capable of communicating with multiple networks (200) using multiple subscriber identity modules, comprising: a control unit (130) that temporarily limits the capability of the communication device used for communication with a second network (200B) when communicating with a first network (200A); Transmitting restriction information to the second network for temporarily restricting the capability. A communication unit (120) Communications equipment.

2. The restriction information is included in a UE assistance information message used for indicating UE assistance information. The communication device according to claim 1 .

3. The restriction information is included in a Multi Universal Subscriber Identity Module (MUSIM) auxiliary information element used to provide MUSIM auxiliary information. The communication device according to claim 2 .

4. The control unit includes at least one of information for restricting a secondary cell, information for restricting a frequency band, and information for restricting a layer of multiple-input multiple-output (MIMO) in the MUSIM auxiliary information element as the restriction information. The communication device according to claim 3.

5. The control unit includes flag information for deactivating or releasing a secondary cell as the restriction information in the MUSIM auxiliary information element. The communication device according to claim 3.

6. The communication unit transmits information for releasing or changing the temporary restriction on the capability to the second network.

3. A communication device according to claim 1 or 2.

7. The communication unit transmits information indicating that the capability is temporarily restricted to the second network; The communication unit transmits the restriction information to the second network after transmitting the information.

3. A communication device according to claim 1 or 2.

8. The information is included in a completion message used to confirm successful completion of a procedure related to a Radio Resource Control (RRC) connection. The communication device according to claim 7.

9. A base station (210B) of a network (200B) in a mobile communication system having a communication device (100) capable of communicating with a plurality of networks (200) using a plurality of subscriber identity modules, A communication unit (212) for receiving, from the communication device communicating with another network (200A), restriction information for temporarily restricting the capability of the communication device used for communication with the other network (200A). Base station.

10. A method of communication performed in a communication device (100) capable of communicating with multiple networks (200) using multiple subscriber identity modules, comprising: temporarily restricting the ability of the communication device to communicate with a second network (200B) when communicating with a first network (200A); transmitting restriction information to the second network for temporarily restricting the capability. Communication methods.