COMMUNICATION DEVICE, BASE STATION, AND COMMUNICATION METHOD

Abstract

To provide user equipment, a base station, and a communication control method to be used in a mobile communication system in which the user equipment efficiently monitors paging in a second network while keeping a connection state in a radio resource control layer with a first network.SOLUTION: User equipment (100) using a plurality of subscriber identification modules to communicate with a plurality of networks (200A, 200B) communicates with a base station (210A) of the first network (200A). The user equipment (100) acquires measurement timing setting indicating timing at which the user equipment (100) is to measure a radio state in the second network (200B). The user equipment (100) transmits a radio resource control (RRC) message including an information element based on the measurement timing setting to the base station (210A).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a user equipment, a base station, and a communication control method for use in a mobile communication system. [Background technology]

[0002] Release 17 of the 3GPP (3rd Generation Partnership Project), a standardization project for mobile communication systems, has launched a work item to define a function that enables user equipment equipped with multiple subscriber identity modules to perform data communications while present in the networks of multiple telecommunications carriers.

[0003] At present, there is no provision in the standard specifications for a mechanism for a user device in the range of multiple networks to receive paging (i.e., incoming calls), and it is dependent on the implementation of the user device. However, if there is an incoming call from one network (hereinafter, "second network") while communicating with another network (hereinafter, "first network"), the user device will miss the incoming call. For this reason, a method of receiving incoming calls from multiple networks in cooperation with each network is being considered in the 3GPP standardization forum (see, for example, Non-Patent Documents 1 to 4).

[0004] Non-Patent Documents 1 to 4 describe a method in which, in a case where a user device equipped with multiple subscriber identity modules has only one receiving unit (RX: Receiver), the first network sets an interruption timing for the user device to temporarily interrupt communication with the first network in order for the user device to monitor paging of the second network while maintaining a connection with the first network. Such an interruption timing is sometimes called a "gap." [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] 3GPP contribution: R2-2009265, “Scenarios and Impact analysis for Switching Notification” [Non-Patent Document 2] 3GPP contribution: R2-2009557, “Switching between two links for Multi-SIM” [Non-Patent Document 3] 3GPP contribution: R2-2010350, “Discussion on switching mechanism for multi-SIM” [Non-Patent Document 4] 3GPP contribution: R2-2100475, “Discussion on Switching Notification Procedure” Summary of the Invention [Problem to be solved by the invention]

[0006] In order for the user equipment to receive paging from the second network, the user equipment needs to measure the radio conditions in the second network prior to monitoring for paging from the second network.

[0007] However, if the first network does not know the transmission setting of the synchronization signal and / or the reference signal of the second network, the first network cannot set an appropriate interruption timing considering the measurement timing of the radio condition of the second network by the user equipment, which causes a problem that it is difficult for the user equipment to efficiently monitor the paging of the second network while maintaining the connection with the first network.

[0008] Therefore, an object of the present invention is to provide a user equipment, a base station, and a communication control method that are capable of efficiently monitoring paging of a second network while maintaining a connection state (RRC_CONNECTED) in a radio resource control (RRC) layer with a first network. [Means for solving the problem]

[0009] A user equipment according to a first aspect communicates with a plurality of networks using a plurality of subscriber identity modules. The user equipment includes a communication unit that communicates with a base station of a first network, and a control unit that acquires a measurement timing configuration indicating a timing for the user equipment to measure a radio condition in a second network. The communication unit transmits a radio resource control (RRC) message including an information element based on the measurement timing configuration to the base station.

[0010] A base station according to a second aspect is a base station of a first network, and includes a communication unit that receives a radio resource control (RRC) message from a user equipment, the radio resource control (RRC) message including an information element based on a measurement timing setting indicating the timing at which the user equipment measures a radio condition in a second network, and a control unit that acquires the information element included in the RRC message.

[0011] A communication control method according to a third aspect is a method executed by a user equipment communicating with a plurality of networks using a plurality of subscriber identity modules, the communication control method comprising the steps of communicating with a base station of a first network, acquiring a measurement timing configuration indicating a timing for the user equipment to measure a radio condition in a second network, and transmitting a radio resource control (RRC) message including an information element based on the measurement timing configuration to the base station. Effect of the Invention

[0012] According to one aspect of the present invention, it is possible to provide a user equipment, a base station, and a communication control method that are capable of efficiently monitoring paging of a second network while maintaining a connection state (RRC_CONNECTED) in a radio resource control (RRC) layer with a first network. [Brief description of the drawings]

[0013] [Figure 1] 1 is a diagram showing an example of the configuration of a mobile communication system according to first and second embodiments. [Diagram 2] FIG. 2 is a diagram illustrating an example of the configuration of a protocol stack in the mobile communication system according to the first and second embodiments. [Diagram 3] FIG. 2 is a diagram illustrating an example of the configuration of a UE (user equipment) according to the first and second embodiments. [Figure 4] FIG. 2 is a diagram illustrating an example of the configuration of a base station of a first network according to the first and second embodiments. [Diagram 5] A diagram showing an example of the operation of a UE for which interruption timing is set by a base station of a first network according to the first and second embodiments. [Figure 6] FIG. 4 is a diagram illustrating a first operation example of the first embodiment. [Figure 7] FIG. 11 is a diagram illustrating a second operation example of the first embodiment. [Figure 8] FIG. 11 is a diagram illustrating a third operation example of the first embodiment. [Figure 9] FIG. 11 is a diagram illustrating a fourth operation example of the first embodiment. [Figure 10] FIG. 11 is a diagram illustrating a first operation example of the second embodiment. [Figure 11] FIG. 11 is a diagram illustrating a second operation example of the second embodiment. [Figure 12] FIG. 11 is a diagram illustrating a third operation example of the second embodiment. [Figure 13] FIG. 13 is a diagram illustrating a fourth operation example of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] 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.

[0015] [First embodiment] The first embodiment will be described with reference to FIGS.

[0016] (System Configuration) A configuration of a mobile communication system 1 according to the first embodiment will be described with reference to Fig. 1. In the following, an example in which the mobile communication system 1 is a 3GPP standard fifth generation system (5G / NR: New Radio) will be mainly described, but a fourth generation system (4G / LTE: Long Term Evolution) system and / or a sixth generation system may be at least partially applied to the mobile communication system 1.

[0017] As shown in FIG. 1, a mobile communication system 1 according to the first embodiment includes a user equipment (UE) 100, a first network 200A, and a second network 200B.

[0018] The UE 100 is a mobile wireless communication device. The UE 100 may be any device used by a user, and may be, for example, 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 (Vehicle UE), or an aircraft or a device provided in an aircraft (Aerial UE).

[0019] The UE 100 is a multi-SIM device that supports multiple subscriber identity modules (SIMs). In the following, an example in which the UE 100 supports two SIMs will be mainly described, but the UE 100 may support three or more SIMs. "Supporting multiple SIMs" means that the UE 100 has the ability to handle multiple SIMs, and the UE 100 does not necessarily have to be equipped with multiple SIMs. Such a UE 100 may be called a "UE that supports multiple SIMs." The SIM is not limited to a card-type SIM (a so-called SIM card), and may be an embedded SIM (a so-called eSIM) that is previously embedded in the UE 100. The SIM may be called a Universal Subscriber Identity Module (USIM).

[0020] 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 to the first network 200A using one SIM, and performs location registration to 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. The first network 200A and the second network 200B may be assigned different PLMN (Public Land Mobile Network) IDs.

[0021] The first network 200A includes a base station 210A constituting a radio access network, and a core network 220A. The core network 220A includes 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 a mobility management device 221B and a gateway device 222B. In the following, when the base stations 210A and 200B are not distinguished, they are simply called the base station 210, when the mobility management devices 221A and 221B are not distinguished, they are simply called the mobility management device 221, and when the gateway devices 222A and 222B are not distinguished, they are simply called the gateway device 222.

[0022] 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 the base station 210 in a radio resource control (RRC) layer with the base station 210. The base station 210 has a radio resource management (RRM) function, a routing function for user data (hereinafter simply referred to as "data"), a measurement control function for mobility control and scheduling, and the like. "Cell" is used as a term indicating the smallest unit of a wireless communication area. "Cell" is also used as a term indicating 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 a cell C1, and the base station 210B manages a cell C2. The UE 100 is located in an overlapping area of ​​the cells C1 and C2.

[0023] 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. In the following, an example in which the base station 210 is a gNB will be mainly described. 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.

[0024] The mobility management device 221 is a device corresponding to the control plane, and is a device that 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 of a 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 an AMF (Access and Mobility Management Function) of 5G / NR, or an MME (Mobility Management Entity) of 4G / LTE.

[0025] 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 User Plane Function (UPF) of 5G / NR or a Serving Gateway (S-GW) of 4G / LTE.

[0026] In the mobile communication system 1 configured as above, a scenario is assumed in which the UE 100 having only one receiving unit (RX: Receiver) performs data communication while existing in the first network 200A and the second network 200B. If the UE 100 receives a paging from the second network 200B while communicating with the first network 200A, the UE 100 cannot receive the paging and misses the incoming call. In order for the UE 100 to monitor the paging of the second network 200B while maintaining the connection with the first network 200A, the first network 200A sets an interruption timing for the UE 100 at which the UE 100 can temporarily interrupt the communication with the first network 200A.

[0027] In order for the UE 100 to receive paging from the second network 200B, the UE 100 needs to measure the radio conditions in the second network 200B before monitoring the paging from the second network 200B. The measurement of the radio conditions includes at least one of a process of receiving a synchronization signal to establish synchronization and a process of performing measurement based on a known signal. That is, in order for the UE 100 to measure the radio conditions in the second network 200B, it is necessary to receive a known signal from the base station 210 of the second network 200B.

[0028] Here, the known signal may be an SSB (SS / PBCH Block). For example, when the base station 210B is a gNB, the known signal used by the UE 100 to measure the radio state may be an SSB (SS / PBCH Block). The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH (Physical Broadcast Channel), and a demodulation reference signal (DMRS). For example, the SSB may be composed of four consecutive OFDM symbols in the time domain. Also, the SSB may be composed of 240 consecutive subcarriers (i.e., 20 resource blocks) in the frequency domain. The PBCH is a physical channel that carries a master information block (MIB). Also, for example, when the base station 210B is an eNB, the known signal used by the UE 100 to measure the radio state may be a PSS and / or an SSS. In the following, an example in which the base station 210B is a gNB will be mainly described, but the base station 210B may be an eNB.

[0029] (Example of protocol stack configuration) An example of the configuration of a protocol stack in the mobile communication system 1 will be described with reference to FIG.

[0030] As shown in FIG. 2, the protocol for the wireless section between UE 100 and base station 210 includes 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.

[0031] 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.

[0032] 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 the UE 100 and the MAC layer of the base station 210 via a transport channel. The MAC layer of the 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 the UE 100.

[0033] The RLC layer transmits data to the RLC layer on the receiving side by 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.

[0034] The PDCP layer performs header compression / decompression and encryption / decryption.

[0035] A Service Data Adaptation Protocol (SDAP) layer may be provided above the PDCP layer. The Service Data Adaptation Protocol (SDAP) layer maps IP flows, which are units for QoS control by the core network, to radio bearers, which are units for QoS control by the access stratum (AS).

[0036] 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 there is an RRC connection 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.

[0037] The NAS layer, which is located 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.

[0038] In addition, the UE 100 has an application layer and the like in addition to the protocol of the radio interface.

[0039] (Example of UE configuration) With reference to FIG. 3, an example of the configuration of UE 100 will be described.

[0040] 3, the UE 100 includes an antenna 101, an SIM 111, an SIM 112, a communication unit 120, and a control unit 130. The antenna 101 may be provided outside the UE 100. The SIM 111 and the SIM 112 are SIM cards or eSIMs.

[0041] 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 International Mobile Subscriber Identity (IMSI).

[0042] 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.

[0043] The communication unit 120 performs wireless communication with the first network 200A and wireless communication with the second network 200B via the antenna 101 under the control of the control unit 130. The communication unit 120 may have only one receiving unit (RX: Receiver) 121. In this case, the communication unit 120 cannot simultaneously receive from the first network 200A and the second network 200B. The communication unit 120 may have only one transmitting unit (TX: Transmitter) 122. However, the communication unit 120 may have multiple transmitting units 122. The receiving unit 121 converts a radio signal received by the antenna 101 into a received signal that is a baseband signal, performs signal processing on the received signal, and outputs the signal to the control unit 130. The transmitting unit 122 performs signal processing on a transmission signal that is a baseband signal output by the control unit 130, converts the signal into a radio signal, and transmits the radio signal from the antenna 101.

[0044] 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 a program executed by the processor and information used in processing by the processor. The memory may include at least one of a ROM, an EPROM, an EEPROM, a RAM, and a flash memory. The processor may include a digital signal processor (DSP) that performs digital processing of a digital signal, and a central processing unit (CPU) that executes a program. Note that a part of the memory may be provided in the communication unit 120. Also, the DSP may be provided in the communication unit 120.

[0045] In the UE 100 configured in this manner, the control unit 130 acquires a measurement timing configuration indicating the timing at which the UE 100 measures the radio state in the second network 200B. That is, the control unit 130 may acquire a measurement timing configuration for measurement based on a known signal in the second network 200B. The measurement timing configuration is, for example, an SMTC (SSB measurement timing configuration) window set in the UE 100 from the base station 210B of the second network 200B. The UE 100 detects and measures the SSB within the set SMTC window. The SMTC window is specified by the setting parameters of the measurement period, offset, and measurement time width of the SSB. The measurement period and offset of the SSB are the period and offset of the measurement window for receiving the SSB, and are given by, for example, the number of subframes. The measurement period is set to one of 5, 10, 20, 40, 80, and 160 ms, and does not necessarily have to be the same as the actual transmission period of the SSB. The measurement time width (also referred to as Duration) is the time length of the measurement window for receiving SSB, and is given by, for example, the number of subframes. Depending on the number of SSBs to be transmitted, one of 1, 2, 3, 4, and 5 ms (i.e., 1, 2, 3, 4, and 5 subframes) is set. When the base station 210B of the second network 200B is an eNB, the timing at which the PSS and / or SSS is transmitted (hereinafter also referred to as the PSS·SSS window) can be used as the measurement timing setting instead of the SMTC window. Then, the control unit 130 generates an RRC message including an information element based on the acquired measurement timing setting. In the first embodiment, the control unit 130 generates an RRC message including the measurement timing setting as an information element. The communication unit 120 transmits this RRC message to the base station 210A of the first network 200A.

[0046] In this manner, by transmitting an RRC message including a measurement timing setting in the second network 200B from the UE 100 to the base station 210A, the base station 210A can grasp the measurement timing at which the UE 100 should measure the radio state of the second network 200B. As a result, the base station 210A can determine an appropriate interruption timing taking into consideration the measurement timing of the UE 100 to measure the radio state of the second network 200B.

[0047] In the first embodiment, the communication unit 120 receives an RRC reconfiguration message including an interruption timing setting indicating the timing to interrupt communication with the base station 210A from the base station 210A after transmitting an RRC message including the measurement timing setting. The RRC reconfiguration message may be an RRCReconfiguration message of 5G / NR or an RRCConnectionReconfiguration message of 4G / LTE. The control unit 130 interrupts communication with the base station 210A and measures the radio state of the second network 200B according to the interruption timing setting received from the base station 210A.

[0048] This allows the UE 100 to measure the radio state of the second network 200B using an interruption timing setting that takes into account the measurement timing setting of the second network 200B. This makes it possible to interrupt communication with the base station 210A for the minimum necessary time, thereby suppressing a decrease in the throughput of communication with the base station 210A. Then, by monitoring paging of the second network 200B after measuring the radio state of the second network 200B, the UE 100 can appropriately receive paging of the second network 200B.

[0049] (Example of base station configuration) An example of the configuration of the base station 210A of the first network 200A will be described with reference to FIG.

[0050] As shown in FIG. 4, the base station 210A includes an antenna 211, a communication unit 212, a network interface 213, and a control unit 214.

[0051] The communication unit 212 communicates with the UE 100 via the antenna 211 under the control of the control unit 214. The communication unit 212 has a receiving unit 212a and a transmitting unit 212b. The receiving unit 212a converts a radio 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 signal to the control unit 214. The transmitting unit 212b performs signal processing on a transmission signal which is a baseband signal output by the control unit 214, converts the transmission signal into a radio signal, and transmits the radio signal from the antenna 211.

[0052] The network interface 213 is connected to the core network 220A. Under the control of the control unit 214, the network interface 213 performs network communication with the mobility management device 221A and the gateway device 222A.

[0053] The control unit 214 controls the 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 a program executed by the processor and information used in the processing by the processor. The memory may include at least one of a ROM, an EPROM, an EEPROM, a RAM, and a flash memory. The processor may include a digital signal processor (DSP) that performs digital processing of a digital signal, and a central processing unit (CPU) that executes the program. Note that a part of the memory may be provided in the communication unit 212. Also, the DSP may be provided in the communication unit 212.

[0054] In the base station 210A configured in this manner, the communication unit 212 receives from the UE 100 an RRC message including an information element based on a measurement timing setting indicating the timing at which the UE 100 measures the radio state in the second network 200B. The control unit 214 acquires the information element included in this RRC message. This allows the control unit 214 to grasp the measurement timing at which the UE 100 should measure the radio state of the second network 200B. As a result, the control unit 214 can determine an appropriate interruption timing taking into consideration the measurement timing of the UE 100 to measure the radio state of the second network 200B.

[0055] In the first embodiment, after receiving the RRC message including the measurement timing setting, the communication unit 212 transmits an RRC reconfiguration message including an interruption timing setting indicating the timing to interrupt communication with the base station 210A to the UE 100. This enables the UE 100 to measure the radio state of the second network 200B using the interruption timing setting that takes into account the measurement timing setting of the second network 200B.

[0056] The interruption timing setting set in the UE 100 includes, for example, an interruption period, which is a period of the interruption timing, and an interruption time width, which is a time width of the interruption timing, as setting parameters. When a measurement gap is used as the interruption timing, a measurement gap setting can be used as the interruption timing setting. Such a measurement gap setting may include, as setting parameters, a measurement gap period, which is a period of the measurement gap, and a measurement gap time width, which is a time width of the measurement gap.

[0057] (Mobile communication system operation) The operation of the mobile communication system 1 will be described with reference to FIGS.

[0058] (1) Example of UE operation An example of the operation of the UE 100 for which the interruption timing is set by the base station 210A of the first network 200A will be described with reference to FIG.

[0059] In the operation example shown in Fig. 5, the UE 100 is in an RRC connected state for the first network 200A, and is in an RRC idle state or an RRC inactive state for the second network 200B. Also, the base station 210B of the second network 200B is a gNB. Therefore, the measurement of the radio state of the second network 200B is an SSB measurement.

[0060] 5, the period from time t1 to time t2 and the period from time t3 to time t4 correspond to interruption timings at which the UE 100 interrupts communication with the base station 210A. Here, an example is shown in which a measurement gap is set as the interruption timing at which the radio condition of the second network 200B is used for measurement.

[0061] During each interruption timing, the control unit 130 of the UE 100 switches the network from which the communication unit 120 receives radio signals from the first network 200A to the second network 200B, and performs measurements on the SSB of the second network 200B, thereby establishing synchronization with the second network 200B and measuring the reception quality.

[0062] The control unit 130 of the UE 100 may monitor paging of the second network 200B after performing measurements on the SSB of the second network 200B during each interruption timing. The monitoring of paging is performed by receiving a PDCCH (Physical Downlink Control CHannel) from the base station 210B of the second network 200B to check whether there is paging addressed to the UE 100. Here, the UE 100 discontinuously monitors paging using discontinuous reception (DRX) in order to reduce power consumption. Such a cycle for monitoring paging is called a DRX cycle. In addition, a frame in which the UE 100 should monitor paging is called a paging frame (PF), and a subframe in this PF in which the UE 100 should monitor paging is called a paging occasion (PO).

[0063] For this reason, the interruption timing may be a period including the timing of the PF / PO set in the UE 100 and the SSB measurement timing (for example, the SMTC window) immediately before the PF / PO. However, the UE 100 does not necessarily need to perform SSB measurement for every PF / PO. For example, if the measurement result (including the state of synchronization) of the second network 200B can be maintained even while the UE 100 is communicating with the first network 200A, the UE 100 may perform SSB measurement at a period longer than the DRX period. For this reason, the interruption timing for the SSB measurement and the interruption timing for the paging monitoring may be set separately.

[0064] Further, the interruption timing for interrupting communication with the base station 210A is not limited to being set in the UE 100 as a measurement gap. The interruption timing for interrupting communication with the base station 210A may be set using a DRX (C-DRX) parameter for the RRC connected state. For example, the base station 210A sets the On Duration and the DRX cycle in the UE 100 so that the period from time t2 to time t3 in FIG. 5 is set as an On Duration, which is a reception-on period, and the period from time t1 to time t2 and the period from time t3 to time t4 are set as reception-off periods. The UE 100 performs SSB measurement and paging monitoring of the second network 200B during the reception-off period set by the base station 210A. For this reason, the interruption timing may be set as a measurement gap or may be set as a reception-off period of DRX.

[0065] (2) First Operation Example of the First Embodiment A first operation example of the first embodiment will be described with reference to FIG.

[0066] Steps S101 and S102: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S101).

[0067] The message including the measurement timing configuration in the second network 200B may be a system information block (SIB) broadcast from the base station 210B. The UE 100 can receive the SIB not only when the UE 100 is in an RRC connected state for the second network 200B, but also when the UE 100 is in an RRC idle state or an RRC inactive state for the second network 200B. Such an SIB may be an SIB used to control cell reselection of the UE 100 in an RRC idle state or an RRC inactive state, for example, an SIB type 2 or SIB type 4 of 5G / NR. The SIB type 2 is an SIB for intra-frequency cell reselection. The SIB type 4 is an SIB for inter-frequency cell reselection. The UE 100 (communication unit 120) receives such an SIB. The UE 100 (control unit 130) acquires the measurement timing configuration included in the SIB (step S102).

[0068] The message including the measurement timing setting in the second network 200B may be an RRC release (RRCRelease) message transmitted from the base station 210B to the UE 100. The RRC release message is a type of RRC message, and is a message for transitioning the UE 100 from an RRC connected state to an RRC idle state or an RRC inactive state. By notifying the UE 100 of the measurement timing setting in the RRC release message, it is possible to set the measurement timing optimized for each UE in the UE 100. The UE 100 (communication unit 120) receives such an RRC release message. The UE 100 (control unit 130) acquires the measurement timing setting included in the RRC release message (step S102).

[0069] The measurement timing setting is not limited to the above-mentioned SMTC window or PSS·SSS window. The measurement timing setting may be any setting information indicating the timing at which the UE 100 measures the radio condition in the second network 200B. The measurement timing setting includes at least one of a measurement period, an offset, and a measurement time width as a setting parameter.

[0070] Step S103: The UE 100 (control unit 130) generates an RRC message including the measurement timing configuration acquired in step S102. Then, the UE 100 (communication unit 120) transmits the RRC message including the measurement timing configuration to the base station 210A of the first network 200A (step S103).

[0071] Here, the RRC message transmitted from the UE 100 to the base station 210A in step S103 may be a message used when establishing, re-establishing, or resuming an RRC connection with the base station 210A. That is, the RRC message transmitted from the UE 100 to the base station 210A may be a message transmitted in association with a random access procedure for the UE 100 to transition from an RRC idle state or an RRC inactive state to an RRC connected state. By notifying the base station 210A of the measurement timing setting in such an RRC message, the base station 210A can grasp the measurement timing setting of the UE 100 at the start of communication between the UE 100 and the base station 210A. Note that the RRC message for establishing an RRC connection with the base station 210A may be an RRCSetupComplete message of 5G / NR or an RRCConnectionSetupComplete message of 4G / LTE. The RRC message for re-establishing the RRC connection with the base station 210A may be an RRCReestablishmentComplete message in 5G / NR or an RRCConnectionReestablishmentComplete message in 4G / LTE. The RRC message for resuming the RRC connection with the base station 210A may be an RRCResumeComplete message.

[0072] The RRC message transmitted from the UE 100 to the base station 210A in step S103 may be an assistance information message transmitted by the UE 100 to the base station 210A as assistance information after the UE 100 establishes, re-establishes, or resumes an RRC connection with the base station 210A. That is, the RRC message transmitted from the UE 100 to the base station 210A may be a message transmitted spontaneously by the UE 100 after transitioning to an RRC connected state. By notifying the base station 210A of the measurement timing setting in such an RRC message, it is possible to prompt the base station 210A to set the interruption timing when the UE 100 determines that measurement and / or paging monitoring of the second network 200B is necessary. Note that such an assistance information message may be a UEAssistanceInformation message or may be an RRC message (e.g., a MultiSIMUEInformation message) newly defined for a multi-SIM supported UE.

[0073] The RRC message transmitted from the UE 100 to the base station 210A in step S103 may be a response message (e.g., UEInformationResponse message) transmitted by the UE 100 in response to a transmission request from the base station 210A after the UE 100 establishes, re-establishes, or resumes an RRC connection with the base station 210A of the first network 200A. The UE 100 may transmit a message used when establishing, re-establishing, or resuming an RRC connection with the base station 210A, including information indicating that the UE 100 has a measurement timing configuration to be transmitted to the base station 210A. Based on the information, the base station 210A transmits a message (e.g., UEInformationRequest message) requesting transmission of the measurement timing configuration to the UE 100. In response to this request message, the UE 100 transmits a response message including the measurement timing configuration to the base station 210A. By notifying the base station 210A of the measurement timing configuration in such a response message, it becomes possible to control such that the measurement timing configuration is requested of the UE 100 only when the base station 210A can set the interruption timing.

[0074] The RRC message transmitted from the UE 100 to the base station 210A in step S103 includes the measurement timing setting as an information element, but may further include other information elements that may be useful for the base station 210A to determine the interruption timing. For example, the RRC message transmitted from the UE 100 to the base station 210A in step S103 may further include at least one information element among 1) the PLMN ID of the second network 200B, 2) the base station ID of the base station 210B, 3) the cell ID of the cell C2 of the base station 210B (i.e., the camped-on cell on which the UE 100 is waiting), 4) the frequency ID of the frequency to which the cell belongs, and 5) information requesting the setting of the interruption timing.

[0075] The base station 210A (communication unit 212) may broadcast, for example, information indicating that transmission of the measurement timing configuration by the UE 100 is permitted, by including the information in an SIB. The UE 100 (communication unit 120) may be able to transmit the measurement timing configuration to the base station 210A only when the base station 210A permits transmission of the measurement timing configuration.

[0076] The base station 210A (the communication unit 212) may broadcast, for example, information indicating a request for acquisition and transmission of the measurement timing configuration by the UE 100, by including the information in an SIB. The UE 100 (the communication unit 120) may transmit the measurement timing configuration to the base station 210A in response to the request from the base station 210A for acquisition and transmission of the measurement timing configuration.

[0077] Step S104: The base station 210A (control unit 214) determines the interruption timing to be set in the UE 100 based on the measurement timing setting received from the UE 100. For example, the base station 210A (control unit 214) determines the period and time width of the interruption timing so as to cover the timing at which the UE 100 measures the second network 200B. The base station 210A (control unit 214) generates an RRC reconfiguration message including an interruption timing setting indicating the determined interruption timing.

[0078] Step S105: The base station 210A (communication unit 212) transmits an RRC reconfiguration message including a suspend timing setting to the UE 100. The UE 100 (communication unit 120) receives this RRC reconfiguration message. The UE 100 (control unit 130) stores and applies the suspend timing setting included in the received RRC reconfiguration message. When a measurement gap is used as the suspend timing, the suspend timing setting may include a measurement gap parameter set for specifying the measurement gap. The measurement gap parameter set may include gapOffset, mgl, mgrp, and mgta. mgl is the measurement gap length of the measurement gap. mgrp is the measurement gap repetition period (MGRP) of the measurement gap. mgta is the measurement gap timing advance. gapOffset is the gap offset of a gap pattern with MGRP.

[0079] Step S106: The UE 100 (communication unit 120) transmits an RRC reconfiguration completion message indicating that the configuration by the RRC reconfiguration message from the base station 210A has been completed to the base station 210A. The base station 210A (communication unit 212) receives the RRC reconfiguration completion message.

[0080] Step S107: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at a timing other than the interruption timing set in the UE 100. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at a timing other than the interruption timing set by the base station 210A.

[0081] Step S108: The base station 210A (control unit 214) does not allocate radio resources to the UE 100 at the interruption timing set for the UE 100, and interrupts communication with the UE 100. The UE 100 (control unit 130) interrupts communication with the base station 210A at the interruption timing set by the base station 210A, and measures the radio state of the second network 200B.

[0082] (3) Second Operation Example of the First Embodiment The second operation example of the first embodiment will be described mainly with respect to the differences from the first operation example of the first embodiment.

[0083] In a second operation example of the first embodiment, the communication unit 120 of the UE 100 receives at least one of the MIB and SIB broadcast from the base station 210B of the second network 200B, and the control unit 130 of the UE 100 acquires a signal transmission configuration included in at least one of the MIB and SIB. The signal transmission configuration indicates the timing at which the base station 210B of the second network 200B transmits at least one of a synchronization signal and a reference signal. The control unit 130 of the UE 100 acquires a measurement timing configuration generated based on the signal transmission configuration. This allows the UE 100 to generate and acquire a measurement timing configuration from the signal transmission configuration of the base station 210B even if the measurement timing configuration is not explicitly set from the base station 210B.

[0084] A second operation example of the first embodiment will be described with reference to FIG.

[0085] Steps S111 and S112: The base station 210B (communication unit 212) of the second network 200B transmits a message including a signal transmission setting in the second network 200B (step S111). The UE 100 (control unit 130) acquires the signal transmission setting included in the message from the base station 210B (step S112).

[0086] For example, in the case of 5G / NR, the signal transmission setting is at least one of subCarrierSpacingCommon included in the MIB broadcast from the base station 210B, ssb-PeriodicityServingCell included in the SIB type 1 broadcast from the base station 210B, and ssb-PositionsInBurst included in the SIB type 1 broadcast from the base station 210B. subCarrierSpacingCommon is an information element indicating the subcarrier spacing. ssb-PeriodicityServingCell is an information element indicating the transmission period of the SSB. ssb-PositionsInBurst is an information element indicating the position of the SSB in the time domain.

[0087] Step S113: The UE 100 (control unit 130) acquires the measurement timing setting generated based on the signal transmission setting acquired in step S112. For example, the UE 100 (control unit 130) generates information corresponding to the SMTC window from the signal transmission setting acquired in step S112, and uses the generated information as the measurement timing setting.

[0088] Step S114: The UE 100 (control unit 130) generates an RRC message including the measurement timing configuration acquired in step S112. Then, the UE 100 (communication unit 120) transmits the RRC message including the measurement timing configuration to the base station 210A of the first network 200A (step S114).

[0089] Steps S115 to S119: This is similar to steps S104 to S108 in the first operation example of the first embodiment.

[0090] (4) Third Operation Example of the First Embodiment The third operation example of the first embodiment will be described, focusing mainly on the differences from the first operation example of the first embodiment.

[0091] In a third operation example of the first embodiment, the control unit 130 of the UE 100 further acquires a paging parameter set for identifying the timing (i.e., PF / PO) at which the UE 100 monitors paging in the second network 200B. The communication unit 120 of the UE 100 transmits an RRC message further including the paging parameter set as another information element to the base station 210A. That is, the paging parameter set is further included in the RRC message transmitted in step S103 of the first operation example of the first embodiment shown in FIG. 6. This allows the base station 210A to know the timing at which the UE 100 should monitor the paging of the second network 200B. As a result, the base station 210A can determine an appropriate interruption timing taking into consideration the timing at which the UE 100 monitors the paging of the second network 200B.

[0092] In a third operation example of the first embodiment, the communication unit 120 of the UE 100 receives an RRC reconfiguration message including an interruption timing setting indicating the timing to interrupt communication with the base station 210A for measuring the radio state and monitoring paging from the base station 210A after transmitting an RRC message. The control unit 130 of the UE 100 interrupts communication with the base station 210A in accordance with the interruption timing setting, and measures the radio state and monitors paging. This allows the UE 100 to monitor paging of the second network 200B using an interruption timing setting that takes into account the paging parameter set of the second network 200B. This makes it possible to interrupt communication with the base station 210A for only the minimum time required for measuring the radio state of the second network 200B and monitoring paging, thereby suppressing a decrease in the throughput of communication with the base station 210A.

[0093] A third operation example of the first embodiment will be described with reference to FIG.

[0094] Steps S121 and S122: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S121). The UE 100 (control unit 130) acquires the measurement timing setting included in the message from the base station 210B (step S122).

[0095] In the third operation example of the first embodiment, the UE 100 (control unit 130) acquires not only the measurement timing configuration but also a paging parameter set (step S122).

[0096] For example, the paging parameter set includes a parameter set for identifying a PF and a PO of paging in the second network 200B. First, the paging parameter set may include configuration information for paging. The configuration information may be PCCH-Config. The configuration information is included in system information transmitted in the second network 200B. The UE 200 (communication unit 120) receives the system information in the second network 200B. Then, the UE 200 (control unit 130) acquires the configuration information included in the system information.

[0097] Secondly, the paging parameter set includes an ID of the UE 100 in the second network 200B. For example, when the base station 210B of the second network 200B is a gNB, the ID is a Temporary Mobile Subscriber Identity (5G-S-TMSI) of the UE 100 in the second network 200B or the least significant 10 bits of the 5G-S-TMSI. When the base station 210B of the second network 200B is an eNB, the ID is an IMSI of the UE 100 in the second network 200B or the least significant 10 bits of the IMSI.

[0098] Here, we will explain how to determine the PF and PO. In the case of 5G / NR, the PF is determined by the following formula:

[0099] (SFN + PF_offset) mod T = (T div N)*(UE_ID mod N) SFN is the system frame number (SFN) of the PF. PF_offset is an offset used to determine the PF. T is the DRX (discontinuous reception) cycle of the UE 100. UE_ID is the least significant 10 bits of the 5G-S-TMSI. N is the total number of PFs in T. For example, T is indicated by defaultPagingCycle included in the PCCH-Config. For example, N and PF_offset are indicated by nAndPagingFrameOffset included in the PCCH-Config.

[0100] For 5G / NR, the PO is determined by the following formula: i_s = floor(UE_ID / N) mod Ns i_s indicates the index of the PO. UE_ID is the least significant 10 bits of 5G-S-TMSI. N is the total number of PFs in T. T is the DRX cycle of UE 100. Ns is the number of POs for a PF. For example, N is indicated by nAndPagingFrameOffset included in PCCH-Config. Ns is indicated by ns included in PCCH-Config. A PO is associated with a PF. For example, a PO starts within or after a PF.

[0101] For 4G / LTE, the PF is determined by the following formula: SFN mod T = (T div N)*(UE_ID mod N) SFN is the SFN of the PF. T is the DRX cycle of the UE 100. N is the smaller of T and nB. nB is a parameter to be configured. UE_ID is the least significant 10 bits of the IMSI. For example, T is indicated by the defaultPagingCycle included in the PCCH-Config. nB is indicated by the nB included in the PCCH-Config.

[0102] For 4G / LTE, the PO is determined by the following formula: i_s = floor(UE_ID / N) mod Ns i_s indicates the index of the PO. UE_ID is the least significant 10 bits of the IMSI. N is the smaller of T and nB. T is the DRX cycle of the UE 100, and nB is a configured parameter. Ns is the larger of 1 and nB / T. For example, T is indicated by the defaultPagingCycle included in the PCCH-Config. nB is indicated by the nB included in the PCCH-Config.

[0103] Step S123: The UE 100 (control unit 130) generates an RRC message including the measurement timing configuration and the paging parameter set acquired in step S122. Then, the UE 100 (communication unit 120) transmits the RRC message including the measurement timing configuration and the paging parameter set to the base station 210A of the first network 200A (step S123).

[0104] Step S124: The base station 210A (control unit 214) determines the interruption timing to be set in the UE 100 based on the measurement timing setting and the paging parameter set received from the UE 100. The base station 210A (control unit 214) determines the period and time width of the interruption timing so as to cover the timing (e.g., SMTC window) at which the UE 100 measures the second network 200B and the timing (e.g., PF / PO) at which the UE 100 monitors paging. The base station 210A (control unit 214) generates an RRC reconfiguration message including an interruption timing setting indicating the determined interruption timing.

[0105] Step S125: The base station 210A (communication unit 212) transmits an RRC reconfiguration message including a suspend timing setting to the UE 100. The UE 100 (communication unit 120) receives this RRC reconfiguration message. The UE 100 (control unit 130) stores and applies the suspend timing setting included in the received RRC reconfiguration message.

[0106] Step S126: The UE 100 (communication unit 120) transmits an RRC reconfiguration completion message indicating that the configuration by the RRC reconfiguration message from the base station 210A has been completed to the base station 210A. The base station 210A (communication unit 212) receives the RRC reconfiguration completion message.

[0107] Step S127: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at a timing other than the interruption timing set in the UE 100. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at a timing other than the interruption timing set by the base station 210A.

[0108] Step S128: The base station 210A (control unit 214) does not allocate radio resources to the UE 100 at the interruption timing set for the UE 100, and interrupts communication with the UE 100. The UE 100 (control unit 130) interrupts communication with the base station 210A at the interruption timing set by the base station 210A, measures the radio state of the second network 200B, and monitors paging of the second network 200B.

[0109] (5) Fourth Operation Example of the First Embodiment The fourth operation example of the first embodiment will be described mainly with respect to the differences from the first operation example of the first embodiment.

[0110] In a fourth operation example of the first embodiment, the communication unit 120 of the UE 100 receives an RRC reconfiguration message from the base station 210A, including a first interruption timing setting indicating the timing to interrupt communication with the base station 210A for measuring the radio state and a second interruption timing setting indicating the timing to interrupt communication with the base station 210A for monitoring paging, after transmitting an RRC message including a measurement timing setting and a paging parameter set. The control unit 130 of the UE 100 interrupts communication with the base station 210A and measures the radio state of the second network 200B according to the first interruption timing setting, and interrupts communication with the base station 210A and monitors paging of the second network 200B according to the second interruption timing setting. This makes it possible to set the interruption timing for measuring the radio state and the interruption timing for monitoring paging separately.

[0111] A fourth operation example of the first embodiment will be described with reference to FIG.

[0112] Steps S131 and S132: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S131). The UE 100 (control unit 130) acquires the measurement timing setting included in the message from the base station 210B (step S132). In the fourth operation example of the first embodiment, the UE 100 (control unit 130) acquires not only the measurement timing setting but also a paging parameter set, similar to the third operation example of the first embodiment (step S132).

[0113] Step S133: The UE 100 (control unit 130) generates an RRC message including the measurement timing configuration and the paging parameter set acquired in step S132. Then, the UE 100 (communication unit 120) transmits the RRC message including the measurement timing configuration and the paging parameter set to the base station 210A of the first network 200A (step S133).

[0114] Step S134: The base station 210A (control unit 214) determines the interruption timing to be set in the UE 100 based on the measurement timing setting and the paging parameter set received from the UE 100. The base station 210A (control unit 214) determines the first interruption timing so as to cover the timing (e.g., SMTC window) at which the UE 100 performs measurement of the second network 200B. The base station 210A (control unit 214) also determines the second interruption timing so as to cover the timing (e.g., PF / PO) at which the UE 100 performs paging monitoring of the second network 200B. The base station 210A (control unit 214) generates an RRC reconfiguration message including a first interruption timing setting indicating the determined first interruption timing and a second interruption timing setting indicating the determined second interruption timing.

[0115] Step S135: The base station 210A (communication unit 212) transmits an RRC reconfiguration message including a first suspend timing setting and a second suspend timing setting to the UE 100. The first suspend timing setting and the second suspend timing setting are included in the RRC reconfiguration message as different information elements. The UE 100 (communication unit 120) receives the RRC reconfiguration message. The UE 100 (control unit 130) stores and applies the first suspend timing setting and the second suspend timing setting included in the received RRC reconfiguration message.

[0116] Step S136: The UE 100 (communication unit 120) transmits an RRC reconfiguration completion message indicating that the configuration by the RRC reconfiguration message from the base station 210A has been completed to the base station 210A. The base station 210A (communication unit 212) receives the RRC reconfiguration completion message.

[0117] Step S137: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at a timing other than the first and second suspension timings set in the UE 100. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at a timing other than the first and second suspension timings set by the base station 210A.

[0118] Step S138: The base station 210A (control unit 214) does not allocate radio resources to the UE 100 and suspends communication with the UE 100 at the first suspension timing and the second suspension timing set for the UE 100. The UE 100 (control unit 130) suspends communication with the base station 210A at the first suspension timing set by the base station 210A and measures the radio state of the second network 200B. In addition, the UE 100 (control unit 130) suspends communication with the base station 210A at the second suspension timing set by the base station 210A and monitors paging of the second network 200B.

[0119] (Summary of the first embodiment) As described above, by transmitting an RRC message including a measurement timing setting in the second network 200B from the UE 100 to the base station 210A of the first network 200A, the base station 210A can grasp the measurement timing at which the UE 100 should measure the radio state of the second network 200B. As a result, the base station 210A can determine an appropriate interruption timing taking into consideration the measurement timing of the UE 100 to measure the radio state of the second network 200B.

[0120] [Second embodiment] The second embodiment will be described mainly with respect to the differences from the first embodiment. The configuration that is the premise of the operation according to the second embodiment is similar to that of the first embodiment.

[0121] (Mobile communication system operation) The operation of the mobile communication system 1 according to the second embodiment will be described with reference to FIGS.

[0122] In the second embodiment, the control unit 130 of the UE 100 determines an interruption timing pattern indicating the timing to interrupt communication with the base station 210A to measure the radio state based on the measurement timing setting. The communication unit 120 of the UE 100 transmits an RRC message including information indicating the determined interruption timing pattern as an information element to the base station 210A. That is, in the second embodiment, the base station 210A does not determine the interruption timing, but the UE 100 determines the interruption timing based on the measurement timing setting, and notifies the base station 210A of the determined interruption timing. This makes it possible to determine an interruption timing optimized according to the capabilities and situation of the UE 100.

[0123] (1) First Operation Example of the Second Embodiment A first operation example of the second embodiment will be described with reference to FIG.

[0124] Steps S201 and S202: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S201). The UE 100 (control unit 130) acquires the measurement timing setting included in the message (step S202).

[0125] The message including the measurement timing configuration in the second network 200B may be an SIB broadcast from the base station 210B or an RRC release (RRCRelease) message transmitted from the base station 210B to the UE 100, as in the first embodiment.

[0126] The measurement timing setting is not limited to the above-mentioned SMTC window or PSS·SSS window. The measurement timing setting may be any setting information indicating the timing at which the UE 100 measures the radio condition in the second network 200B. The measurement timing setting includes at least one of a measurement period, an offset, and a measurement time width as a setting parameter.

[0127] Step S203: The UE 100 (control unit 130) determines an interruption timing pattern indicating an interruption timing for interrupting communication with the base station 210A based on the measurement timing setting acquired in step S202. For example, the UE 100 (control unit 130) determines a period and a time width of the interruption timing so as to cover the timing when the UE 100 performs the measurement of the second network 200B.

[0128] Step S204: The UE 100 (control unit 130) generates an RRC message including, as an information element, information indicating the interruption timing pattern determined in step S203. Then, the UE 100 (communication unit 120) transmits the RRC message to the base station 210A of the first network 200A (step S204).

[0129] As in the first embodiment, the RRC message transmitted from UE100 to base station 210A in step S203 may be any one of the following: 1) a message used when establishing, re-establishing, or resuming an RRC connection with the base station 210A; 2) an auxiliary information message transmitted by UE100 to the base station 210A as auxiliary information after UE100 establishes, re-establishes, or resumes an RRC connection with the base station 210A; or 3) a response message transmitted by UE100 in response to a transmission request from the base station 210A after UE100 establishes, re-establishes, or resumes an RRC connection with the base station 210A of the first network 200A.

[0130] The RRC message transmitted from the UE 100 to the base station 210A in step S204 includes information indicating the suspension timing pattern as an information element, but may further include other information elements. For example, the RRC message transmitted from the UE 100 to the base station 210A in step S204 may further include at least one information element among 1) the PLMN ID of the second network 200B, 2) the base station ID of the base station 210B, 3) the cell ID of the cell C2 of the base station 210B (i.e., the camped-on cell on which the UE 100 is waiting), 4) the frequency ID of the frequency to which the cell belongs, and 5) information requesting setting of the suspension timing.

[0131] The base station 210A (communication unit 212) may broadcast information indicating that the UE 100 is permitted to determine the interruption timing pattern, for example, by including the information in an SIB. The UE 100 (communication unit 120) may be able to determine the interruption timing pattern only when the base station 210A permits the setting of the measurement timing configuration.

[0132] Steps S205 and S206: The base station 210A (communication unit 212) may transmit to the UE 100 an RRC reconfiguration message including an interruption timing setting based on the interruption timing pattern determined by the UE 100 (step S205). In this case, when the UE 100 (communication unit 120) receives the RRC reconfiguration message, the UE 100 (control unit 130) stores and applies the interruption timing setting included in the received RRC reconfiguration message. In addition, the UE 100 (communication unit 120) may transmit to the base station 210A an RRC reconfiguration completion message indicating that the setting by the RRC reconfiguration message from the base station 210A has been completed (step S206). Note that steps S205 and S206 are not essential and can be omitted.

[0133] Step S207: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at timings other than the suspension timings. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at timings other than the suspension timings.

[0134] Step S208: At the interruption timing, the base station 210A (control unit 214) does not allocate radio resources to the UE 100, and interrupts communication with the UE 100. At the interruption timing, the UE 100 (control unit 130) interrupts communication with the base station 210A and measures the radio state of the second network 200B.

[0135] (2) Second Operation Example of Second Embodiment The second operation example of the second embodiment will be described mainly with respect to the differences from the first operation example of the second embodiment.

[0136] In a second operation example of the first embodiment, the communication unit 120 of the UE 100 receives at least one of the MIB and SIB broadcast from the base station 210B of the second network 200B, and the control unit 130 of the UE 100 acquires a signal transmission configuration included in at least one of the MIB and SIB. The signal transmission configuration indicates the timing at which the base station 210B of the second network 200B transmits at least one of a synchronization signal and a reference signal. The control unit 130 of the UE 100 acquires a measurement timing configuration generated based on the signal transmission configuration. This allows the UE 100 to generate and acquire a measurement timing configuration from the signal transmission configuration of the base station 210B even if the measurement timing configuration is not explicitly set from the base station 210B.

[0137] A second operation example of the second embodiment will be described with reference to FIG.

[0138] Steps S211 and S212: The base station 210B (communication unit 212) of the second network 200B transmits a message including a signal transmission setting in the second network 200B (step S211). The UE 100 (control unit 130) acquires the signal transmission setting included in the message from the base station 210B (step S212).

[0139] Step S213: The UE 100 (control unit 130) acquires the measurement timing setting generated based on the signal transmission setting acquired in step S212. For example, the UE 100 (control unit 130) generates information corresponding to the SMTC window from the signal transmission setting acquired in step S212, and uses the generated information as the measurement timing setting.

[0140] Step S214: The UE 100 (control unit 130) determines an interruption timing pattern indicating an interruption timing for interrupting communication with the base station 210A based on the measurement timing setting acquired in step S213. For example, the UE 100 (control unit 130) determines a period and a time width of the interruption timing so as to cover the timing at which the UE 100 measures the second network 200B.

[0141] Step S215: The UE 100 (control unit 130) generates an RRC message including, as an information element, information indicating the interruption timing pattern determined in step S214. Then, the UE 100 (communication unit 120) transmits the RRC message to the base station 210A of the first network 200A (step S204).

[0142] Steps S216 to S219: This is similar to steps S205 to S208 in the first operation example of the second embodiment.

[0143] (3) Third Operation Example of the Second Embodiment The third operation example of the second embodiment will be described mainly with respect to the differences from the first operation example of the second embodiment.

[0144] In a third operation example of the second embodiment, the control unit 130 of the UE 100 further acquires a paging parameter set for identifying the timing (i.e., PF / PO) at which the UE 100 monitors paging in the second network 200B. Then, the control unit 130 of the UE 100 determines an interruption timing pattern indicating an interruption timing at which communication with the base station 210A is interrupted for measuring the radio state and monitoring paging, based on the measurement timing configuration and the paging parameter set. This allows the UE 100 to determine an appropriate interruption timing taking into account the paging monitoring timing of the second network 200B.

[0145] A third operation example of the second embodiment will be described with reference to FIG.

[0146] Steps S221 and S222: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S221). The UE 100 (control unit 130) acquires the measurement timing setting included in the message (step S222). In a third operation example of the second embodiment, the UE 100 (control unit 130) acquires not only the measurement timing setting but also a paging parameter set (step S222). Details of the paging parameter set are the same as those in the third operation example of the first embodiment.

[0147] Step S223: The UE 100 (control unit 130) determines an interruption timing pattern indicating an interruption timing for interrupting communication with the base station 210A based on the measurement timing configuration and the paging parameter set acquired in step S222. For example, the UE 100 (control unit 130) determines a period and a time width of the interruption timing so as to cover the timing when the UE 100 measures the second network 200B and the timing when the UE 100 monitors paging.

[0148] Step S224: The UE 100 (control unit 130) generates an RRC message including, as an information element, information indicating the interruption timing pattern determined in step S223. Then, the UE 100 (communication unit 120) transmits the RRC message to the base station 210A of the first network 200A (step S224).

[0149] Steps S225 and S226: This is similar to steps S205 and S206 in the first operation example of the second embodiment.

[0150] Step S227: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at timings other than the suspension timings. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at timings other than the suspension timings.

[0151] Step S228: At the interruption timing, the base station 210A (control unit 214) does not allocate radio resources to the UE 100 and interrupts communication with the UE 100. At the interruption timing, the UE 100 (control unit 130) interrupts communication with the base station 210A, measures the radio state of the second network 200B, and monitors paging of the second network 200B.

[0152] (4) Fourth Operation Example of the Second Embodiment The fourth operation example of the second embodiment will be described mainly with respect to differences from the first operation example of the second embodiment.

[0153] In a fourth operation example of the second embodiment, the control unit 130 of the UE 100 further acquires a paging parameter set for identifying the timing at which the UE 100 monitors paging in the second network 200B. The control unit 130 of the UE 100 determines a first interruption timing pattern indicating the timing at which communication with the base station 210A is stopped for measuring the radio state based on the measurement timing setting. The control unit 130 of the UE 100 also determines a second interruption timing pattern indicating the timing at which communication with the base station 210A is stopped for monitoring paging based on the paging parameter set. Then, the communication unit 120 of the UE 100 transmits an RRC message including information indicating the first interruption timing pattern and information indicating the second interruption timing pattern to the base station 210A. This makes it possible to set the interruption timing for measuring the radio state and the interruption timing for monitoring paging separately.

[0154] A fourth operation example of the second embodiment will be described with reference to FIG.

[0155] Steps S231 and S232: The base station 210B (communication unit 212) of the second network 200B transmits a message including a measurement timing setting in the second network 200B (step S231). The UE 100 (control unit 130) acquires the measurement timing setting included in the message from the base station 210B (step S232). In the fourth operation example of the second embodiment, the UE 100 (control unit 130) acquires not only the measurement timing setting but also a paging parameter set (step S232), similar to the third operation example of the second embodiment.

[0156] Step S233: The UE 100 (control unit 130) determines a first interruption timing pattern indicating a first interruption timing at which communication with the base station 210A is stopped to measure the radio state based on the measurement timing setting acquired in step S232. Also, the UE 100 (control unit 130) determines a second interruption timing pattern indicating a second interruption timing at which communication with the base station 210A is stopped to monitor paging based on the paging parameter set.

[0157] Step S234: The UE 100 (control unit 130) generates an RRC message including information indicating the first suspend timing pattern determined in step S233 and information indicating the second suspend timing pattern determined in step S233. Then, the UE 100 (communication unit 120) transmits the RRC message to the base station 210A of the first network 200A (step S224).

[0158] Steps S235 and S236: This is similar to steps S205 and S206 in the first operation example of the second embodiment.

[0159] Step S237: The base station 210A (control unit 214) allocates radio resources to the UE 100 and communicates with the UE 100 at a timing other than the first suspension timing and the second suspension timing. The UE 100 (control unit 130) monitors the PDCCH of the base station 210A and communicates with the base station 210A at a timing other than the first suspension timing and the second suspension timing.

[0160] Step S238: The base station 210A (control unit 214) does not allocate radio resources to the UE 100 at the first and second interruption timings, and interrupts communication with the UE 100. The UE 100 (control unit 130) interrupts communication with the base station 210A at the first interruption timing, and measures the radio state of the second network 200B. In addition, the UE 100 (control unit 130) interrupts communication with the base station 210A at the second interruption timing, and monitors paging of the second network 200B.

[0161] (Summary of the second embodiment) As described above, the UE 100 determines the interruption timing based on the measurement timing setting in the second network 200B, so that an appropriate interruption timing can be determined taking into consideration the timing at which the UE 100 measures the radio state of the second network 200B.

[0162] [Other embodiments] The steps in the operations of the above-described embodiments do not necessarily have to be executed in chronological order according to the order described in the flow diagram or sequence diagram. For example, the steps in the operations may be executed in an order different from that described in the flow diagram or sequence diagram, or may be executed in parallel. Some of the steps in the operations may be deleted, and additional steps may be added to the process. Furthermore, each of the above-described operation flows is not limited to being executed separately and independently, but may be executed by combining two or more operation flows. For example, some steps of one operation flow may be added to another operation flow, or some steps of one operation flow may be replaced with some steps of another operation flow.

[0163] 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 in a computer-readable medium. Using the computer-readable medium, it is possible to install the program in the computer. Here, the computer-readable medium on which the program is recorded may be a non-transient recording medium. The non-transient recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM or a DVD-ROM. In addition, a circuit that executes 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).

[0164] In the above embodiment, "transmit" may mean performing processing of at least one layer in a protocol stack used for transmission, or may mean physically transmitting a signal wirelessly or by wire. Alternatively, "transmit" may mean a combination of performing processing of at least one layer and physically transmitting a signal wirelessly or by wire. Similarly, "receive" may mean performing processing of at least one layer in a protocol stack used for reception, or may mean physically receiving a signal wirelessly or by wire. Alternatively, "receive" may mean a combination of performing processing of at least one layer and physically receiving a signal wirelessly or by wire.

[0165] The above describes the embodiments in detail with reference to the drawings, but the specific configuration is not limited to that described above, and various design changes, etc. are possible without departing from the spirit of the invention. [Explanation of symbols]

[0166] 1: Mobile communication systems 100:UE 101: Antenna 120: Communications Department 121: Receiving unit 122: Transmitter 130: Control section 200:Base station 200A: First network 200B: Second network 210A:Base station 210B:Base station 211: Antenna 212: Communications Department 212a: Receiving section 212b: Transmitter 213: Network interface 214: Control section 220A: Core Network 220B: Core Network 221A: Mobility management device 221B: Mobility management device 222A: Gateway device 222B: Gateway device

Claims

1. A communication device (100) for communicating with a plurality of networks (200A, 200B) using a plurality of subscriber identity modules (111, 112), a communication unit (120) that communicates with a base station (210A) of a first network (200A) included in the plurality of networks (200A, 200B); The communication unit (120) receiving information from the base station (210A) indicating that the communication device (100) determines and transmits a gap pattern to be set; Based on receiving the information, sending a UEAssistanceInformation message to the base station (210A) including information indicating the gap pattern; The information indicating the gap pattern includes first information indicating a first gap pattern having a first repetition period and second information indicating a second gap pattern having a second repetition period. A communication device (100).

2. The gap pattern is a pattern of gaps for performing an operation in a second network (200B) included in the plurality of networks (200A, 200B), and includes a gap length, a gap repetition period, and a gap offset. The communication device according to claim 1 .

3. The communication unit (120) receives an RRC reconfiguration message including a first gap setting according to the first information and a second gap setting according to the second information from the base station (210A). The communication device (100) of claim 1.

4. A control unit (130) for monitoring paging and measuring radio conditions in the second network (200B) in the gap pattern, The control unit (130) performs control not to monitor paging and not to measure radio conditions in the second network (200B) during periods other than the gap pattern. The communication device (100) of claim 2.

5. the first repetition period corresponds to a period for the communication device (100) to monitor paging in a second network (200B) included in the plurality of networks (200A, 200B); The second repetition period corresponds to a period for the communication device (100) to measure radio conditions in the second network (200B). The communication device (100) of claim 1.

6. A base station (210A) of a first network (200A), A transmission unit that transmits, to the communication device (100), information indicating that the communication device (100) determines and transmits the gap pattern to be set; A receiving unit that receives a UEAssistanceInformation message including information indicating the gap pattern to be set from the communication device (100), The information indicating the gap pattern includes first information indicating a first gap pattern having a first repetition period and second information indicating a second gap pattern having a second repetition period. Base station (210A).

7. The gap pattern is a pattern of gaps for performing an operation in a second network (200B) included in the plurality of networks (200A, 200B), and includes a gap length, a gap repetition period, and a gap offset. The base station (210A) of claim 6.

8. The transmitting unit transmits an RRC reconfiguration message including a first gap setting according to the first information and a second gap setting according to the second information to the communication device (100). The base station (210A) of claim 6.

9. A communication control method executed by a communication device (100) that communicates with a plurality of networks (200A, 200B) using a plurality of subscriber identity modules (111, 112), comprising: receiving information from a first network (200A) indicating that the communication device (100) determines and transmits a gap pattern to be set; and transmitting a UEAssistanceInformation message to the first network (200A) based on the reception of the information, the UEAssistanceInformation message including information indicating the gap pattern to be set; The information indicating the gap pattern includes first information indicating a first gap pattern having a first repetition period and second information indicating a second gap pattern having a second repetition period. Communication methods.

10. The gap pattern is a pattern of gaps for performing an operation in a second network (200B) included in the plurality of networks (200A, 200B), and includes a gap length, a gap repetition period, and a gap offset. The communication method according to claim 9.

11. and receiving an RRC reconfiguration message from the first network (200A) including a first gap configuration according to the first information and a second gap configuration according to the second information. The communication method according to claim 9.

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