Terminal equipment, base station equipment, and method

Abstract

In the present invention, a terminal device comprises: a reception unit that receives, from a base station device, a first RRC message which includes a parameter for synchronization resetting for SpCell of a first cell group; a processing unit that processes the first RRC message; and a transmission unit that transmits a random access preamble in the SpCell in response to the reception of the first RRC message. The processing unit determines whether to transmit the random access preamble in the SpCell depending on whether the first RRC message includes first information.

Description

Technical Field

[0001] The present invention relates to a terminal device, a base station device, and a method. This application claims priority to Japanese Patent Application No. 2020-173018, filed in Japan on October 14, 2020, the content of which is incorporated herein by reference. <000,006>

Background Art

[0002] In the 3rd Generation Partnership Project (3GPP), which is a standardization project for cellular mobile communication systems, technical studies and standard setting for cellular mobile communication systems, including radio access, core network, services, etc., are being carried out.

[0003] For example, in 3GPP, E-UTRA (Evolved Universal Terrestrial Radio Access) was started for technical studies and standard setting as a radio access technology (RAT) for cellular mobile communication systems for the 3.9th and 4th generations. Even now, in 3GPP, technical studies and standard setting for extended technologies of E-UTRA are being carried out. Note that E-UTRA is also referred to as Long Term Evolution (LTE: registered trademark), and extended technologies may be referred to as LTE-Advanced (LTE-A) and LTE-Advanced Pro (LTE-A Pro).

[0004] Also, in 3GPP, NR (New Radio, or NR Radio access) was started for technical studies and standard setting as a radio access technology (RAT) for cellular mobile communication systems for the 5th generation (5G). Even now, in 3GPP, technical studies and standard setting for extended technologies of NR are being carried out.

Prior Art Documents

Non-Patent Documents

[0005] [Non-Patent Document 1] 3GPP TS 38.300v 16.2.0,"NR;NR and NG-RAN Overall description; Stage 2" pp10-134 [Non-Patent Document 2] 3GPP TS 36.300 v16.2.0,"Evolved Universal Terrestrial Radio Access (E-UTRA)and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2" pp19-361 [Non-Patent Document 3] 3GPP TS 38.331 v16.2.0,"NR;Radio Resource Control (RRC);Protocol specifications"pp21-861 [Non-Patent Document 4] 3GPP TS 36.331 v16.1.0,"Evolved Universal Terrestrial Radio Access (E-UTRA);Radio Resource Control (RRC);Protocol specifications" pp25-1012 [Non-Patent Document 5] 3GPP TS 37.340 v16.2.0,"EvolvedUniversal Terrestrial Radio Access (E-UTRA)and NR; Multi-Connectivity; Stage 2" pp6-67 [Non-Patent Document 6] 3GPP TS 38.321 v16.1.0, "NR;Medium Access Control (MAC) protocol specification" pp8-148 [Overview of the project] [Problems that the invention aims to solve]

[0006] As an extension of NR (New Radio), dual connectivity (also called multi-connectivity) technology enables high-capacity data communication by using multiple cell groups, allowing one or more base station devices and terminal devices to communicate. In this dual connectivity, terminal devices need to monitor each cell group for the presence of messages addressed to them in order to communicate within each cell group. Terminal devices need to constantly monitor multiple cell groups to enable low-latency communication when high-capacity data communication occurs, which has the problem of consuming a lot of power. Therefore, technologies that allow monitoring of some cell groups to be performed at a low frequency or stopped (cell group deactivation technology) are being considered.

[0007] In addition to the operation of the terminal device in the inactive state of the cell group, it is also necessary to consider the operation of the terminal device when it is activated (recovers) from the inactive state.

[0008] One aspect of the present invention has been made in view of the above circumstances, and one of its objectives is to provide a terminal device, a base station device, and a method that can efficiently perform communication control. [Means for solving the problem]

[0009] To achieve the above objective, one aspect of the present invention employs the following means. That is, one aspect of the present invention is a terminal device that communicates with a base station device, comprising: a receiving unit that receives a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a first cell group's SpCell; a processing unit that processes the first RRC message; and a transmitting unit that transmits a random access preamble in the SpCell based on the reception of the first RRC message, wherein the processing unit determines whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0010] Another aspect of the present invention is a base station device that communicates with a terminal device, comprising: a transmitting unit that transmits a first RRC message to the terminal device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group; and a receiving unit that receives a random access preamble transmitted from the terminal device by the SpCell based on the first RRC message, wherein the terminal device is instructed to determine whether or not to transmit the random access preamble in the SpCell depending on whether or not the first RRC message includes first information.

[0011] Another aspect of the present invention is a method applied to a terminal device that communicates with a base station device, comprising the steps of: receiving a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group; processing the first RRC message; and transmitting a random access preamble in the SpCell based on the reception of the first RRC message, wherein it is determined whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0012] Another aspect of the present invention is a method applied to a base station device that communicates with a terminal device, comprising the steps of: sending a first RRC message to the terminal device containing parameters for synchronous reconfiguration of a SpCell of a first cell group; and receiving a random access preamble transmitted by the SpCell from the terminal device based on the first RRC message, wherein the terminal device determines whether or not to transmit the random access preamble in the SpCell depending on whether or not the first information is included in the first RRC message.

[0013] Another aspect of the present invention is an integrated circuit implemented in a terminal device that communicates with a base station device, which causes the terminal device to perform the following functions: receiving a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a first cell group's SpCell; processing the first RRC message; and transmitting a random access preamble in the SpCell based on the reception of the first RRC message, and determining whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0014] Another aspect of the present invention is an integrated circuit implemented in a base station device that communicates with a terminal device, wherein the base station device is given the function of transmitting a first RRC message to the terminal device that includes parameters for synchronous reconfiguration of a first cell group's SpCell, and the base station device is given the function of receiving a random access preamble transmitted from the terminal device by the SpCell based on the first RRC message, and the terminal device is given the function of determining whether or not to transmit the random access preamble in the SpCell depending on whether or not the first information is included in the first RRC message.

[0015] Note that these general or specific aspects may be implemented in a system, apparatus, method, integrated circuit, computer program, or recording medium, or may be implemented in any combination of a system, apparatus, method, integrated circuit, computer program, and recording medium.

Advantages of the Invention

[0016] According to one aspect of the present invention, a terminal device, a base station device, a method, and an integrated circuit can realize efficient communication control processing.

Brief Description of the Drawings

[0017] [Figure 1] Schematic diagram of a communication system according to an embodiment of the present invention. [Figure 2] Diagram of an example of an E-UTRA protocol configuration according to an embodiment of the present invention. [Figure 3] Diagram of an example of an NR protocol configuration according to an embodiment of the present invention. [Figure 4] Diagram showing an example of a flow of procedures for various settings in RRC according to an embodiment of the present invention. [Figure 5] Block diagram showing the configuration of a terminal device in an embodiment of the present invention. [Figure 6] Block diagram showing the configuration of a base station device in an embodiment of the present invention. [Figure 7] Example of an ASN.1 description included in a message regarding reconfiguration of an RRC connection in NR according to an embodiment of the present invention. [Figure 8] Example of an ASN.1 description included in a message regarding reconfiguration of an RRC connection in E-UTRA according to an embodiment of the present invention. [Figure 9] Example of an ASN.1 description of an RRC reconfiguration message according to an embodiment of the present invention. [Figure 10] Example of an ASN.1 description of a cell group setting information element according to an embodiment of the present invention. [Figure 11] Example of an ASN.1 description of the setting of a SpCell according to an embodiment of the present invention. [Figure 12] An example of ASN.1 description for a synchronized reset information element in an embodiment of the present invention. [Figure 13] An example of ASN.1 description of a ServingCellConfigCommon information element in an embodiment of the present invention. [Figure 14] An example of ASN.1 description of SCell configuration information elements in an embodiment of the present invention. [Figure 15] An example of processing by a terminal device in an embodiment of the present invention. [Modes for carrying out the invention]

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0019] LTE (and LTE-A, LTE-A Pro) and NR may be defined as different Radio Access Technologies (RATs). NR may also be defined as a technology included in LTE. Furthermore, LTE that can connect with NR via Multi Radio Dual connectivity (MR-DC) may be distinguished from conventional LTE. Furthermore, LTE using 5GC in the core network may be distinguished from conventional LTE using EPC in the core network. Conventional LTE may refer to LTE that does not implement technologies standardized in 3GPP Release 15 or later. Embodiments of the present invention may be applied to NR, LTE, and other RATs. The following description uses terms related to LTE and NR, but embodiments of the present invention may be applied to other technologies using other terms. Also, the term E-UTRA in embodiments of the present invention may be replaced with the term LTE, and the term LTE may be replaced with the term E-UTRA.

[0020] In the embodiments of the present invention, the names of each node and entity, and the processing at each node and entity, will be described when the wireless access technology is E-UTRA or NR. However, the embodiments of the present invention may be used with other wireless access technologies. The names of each node and entity in the embodiments of the present invention may be different.

[0021] Figure 1 is a schematic diagram of a communication system according to an embodiment of the present invention. The functions of each node, wireless access technology, core network, interface, etc., described using Figure 1 are some of the functions closely related to the embodiment of the present invention, and other functions may be present.

[0022] E-UTRA100 may be a wireless access technology. E-UTRA100 may also be an air interface between UE122 and eNB102. The air interface between UE122 and eNB102 may be called the Uu interface. eNB (E-UTRAN Node B)102 may be the base station equipment for E-UTRA100. eNB102 may have the E-UTRA protocol described below. The E-UTRA protocol may consist of the E-UTRA User Plane (UP) protocol and the E-UTRA Control Plane (CP) protocol described below. eNB102 may terminate the E-UTRA User Plane (UP) protocol and the E-UTRA Control Plane (CP) protocol to UE122. The wireless access network configured with eNB may be called E-UTRAN.

[0023] EPC (Evolved Packet Core) 104 may be a core network. Interface 112 is an interface between eNB 102 and EPC 104 and may be called an S1 interface. Interface 112 may have a control plane interface through which control signals pass, and / or a user plane interface through which user data passes. The control plane interface of interface 112 may terminate at a Mobility Management Entity (MME: not shown) in EPC 104. The user plane interface of interface 112 may terminate at a Serving Gateway (S-GW: not shown) in EPC 104. The control plane interface of interface 112 may be called an S1-MME interface. The user plane interface of interface 112 may be called an S1-U interface.

[0024] One or more eNB102s may be connected to the EPC104 via interface 112. Interfaces may exist between multiple eNB102s connected to the EPC104 (not shown). Interfaces between multiple eNB102s connected to the EPC104 may be called X2 interfaces.

[0025] NR106 may be a wireless access technology. NR106 may also be an air interface between UE122 and gNB108. The air interface between UE122 and gNB108 may be called the Uu interface. gNB108 may be the base station equipment for NR106. gNB108 may have the NR protocol described below. The NR protocol may consist of the NR User Plane (UP) protocol and the NR Control Plane (CP) protocol described below. gNB108 may terminate the NR User Plane (UP) protocol and the NR Control Plane (CP) protocol to UE122.

[0026] 5GC110 may be the core network. Interface 116 is the interface between gNB108 and 5GC110 and may be called the NG interface. Interface 116 may have a control plane interface through which control signals pass, and / or a user plane interface through which user data passes. The control plane interface of interface 116 may be terminated by the Access and Mobility Management Function (AMF: not shown) in 5GC110. The user plane interface of interface 116 may be terminated by the User Plane Function (UPF: not shown) in 5GC110. The control plane interface of interface 116 may be called the NG-C interface. The user plane interface of interface 116 may be called the NG-U interface.

[0027] One or more gNB108s may be connected to the 5GC110 via interface 116. Interfaces may exist between multiple gNB108s connected to the 5GC110 (not shown). The interfaces between multiple gNB108s connected to the 5GC110 may be called Xn interfaces.

[0028] eNB102 may have the function to connect to 5GC110. eNB102 having the function to connect to 5GC110 may be called ng-eNB. Interface 114 is the interface between eNB102 and 5GC110 and may be called NG interface. Interface 114 may have a control plane interface through which control signals pass, and / or a user plane interface through which user data passes. The control plane interface of interface 114 may be terminated at the Access and Mobility Management Function (AMF: not shown) in 5GC110. The user plane interface of interface 114 may be terminated at the User Plane Function (UPF: not shown) in 5GC110. The control plane interface of interface 114 may be called NG-C interface. The user plane interface of interface 114 may be called NG-U interface. A wireless access network consisting of ng-eNB or gNB may be called NG-RAN. NG-RAN, E-UTRAN, eNB, ng-eNB, and gNB may simply be called a network.

[0029] One or more eNB102s may be connected to the 5GC110 via interface 114. Interfaces may exist between multiple eNB102s connected to the 5GC110 (not shown). Interfaces between multiple eNB102s connected to the 5GC110 may be called Xn interfaces. Furthermore, an eNB102 connected to the 5GC110 and a gNB108 connected to the 5GC110 may be connected via interface 120. Interface 120 between an eNB102 connected to the 5GC110 and a gNB108 connected to the 5GC110 may be called Xn interfaces.

[0030] gNB108 may have the function of connecting to EPC104. gNB108 with the function of connecting to EPC104 may be called en-gNB. Interface 118 is the interface between gNB108 and EPC104 and may be called the S1 interface. Interface 118 may have a user plane interface through which user data passes. The user plane interface of interface 118 may be terminated at the S-GW (not shown) in EPC104. The user plane interface of interface 118 may be called the S1-U interface. Also, eNB102 connected to EPC104 and gNB108 connected to EPC104 may be connected by interface 120. Interface 120 between eNB102 connected to EPC104 and gNB108 connected to EPC104 may be called the X2 interface.

[0031] Interface 124 is the interface between EPC104 and 5GC110, and may be an interface that passes only CP, only UP, or both CP and UP. In addition, some or all of interfaces such as Interface 114, Interface 116, Interface 118, Interface 120, and Interface 124 may not exist depending on the communication system provided by the telecommunications carrier.

[0032] UE122 may be a terminal device capable of receiving broadcast information and paging messages transmitted from eNB102 and / or gNB108. UE122 may also be a terminal device capable of wireless connection with eNB102 and / or gNB108. Furthermore, UE122 may be a terminal device capable of simultaneously establishing wireless connections with eNB102 and gNB108. UE122 may have the E-UTRA protocol and / or the NR protocol. Note that the wireless connection may be a Radio Resource Control (RRC) connection.

[0033] When UE122 communicates with eNB102 and / or gNB108, a wireless connection may be established by establishing a radio bearer (RB) between UE122 and eNB102 and / or gNB108. The radio bearer used for CP may be called a signaling radio bearer (SRB). The radio bearer used for UP may be called a data radio bearer (DRB). Each radio bearer may be assigned a radio bearer identifier (Identity: ID). The radio bearer identifier for SRB may be called an SRB identifier (SRB Identity, or SRB ID). The radio bearer identifier for DRB may be called a DRB identifier (DRB Identity, or DRB ID).

[0034] Furthermore, UE122 may be a terminal device capable of connecting to EPC104 and / or 5GC110 via eNB102 and / or gNB108. If the core network to which eNB102 and / or gNB108, with which UE122 communicates, is connected is EPC104, then each DRB established between UE122 and eNB102 and / or gNB108 may be uniquely associated with each EPS (Evolved Packet System) bearer passing through EPC104. Each EPS bearer may be identified by an EPS bearer identifier (Identity, or ID). Furthermore, the same QoS may be guaranteed for data such as IP packets and Ethernet® frames passing through the same EPS bearer.

[0035] Furthermore, if the core network to which UE122 communicates with eNB102 and / or gNB108 is connected is 5GC110, then each DRB established between UE122 and eNB102 and / or gNB108 may be further associated with one of the PDU (Packet Data Unit) sessions established within 5GC110. Each PDU session may have one or more QoS flows. Each DRB may be mapped to one or more QoS flows, or may not be mapped to any QoS flow. Each PDU session may be identified by a PDU session identifier (Identity, Identifier, or ID). Each QoS flow may also be identified by a QoS flow identifier (Identity, Identifier, or ID). In addition, the same QoS may be guaranteed for data such as IP packets and Ethernet frames passing through the same QoS flow.

[0036] EPC104 does not need to have PDU sessions and / or QoS flows. Similarly, 5GC110 does not need to have an EPS bearer. When UE122 is connected to EPC104, UE122 will have information about the EPS bearer, but it does not need to have information about the PDU sessions and / or QoS flows. Similarly, when UE122 is connected to 5GC110, UE122 will have information about the PDU sessions and / or QoS flows, but it does not need to have information about the EPS bearer.

[0037] In the following description, eNB102 and / or gNB108 will also be simply referred to as base station equipment, and UE122 will also be simply referred to as terminal equipment or UE.

[0038] Figure 2 is a diagram of an example of the E-UTRA protocol architecture according to an embodiment of the present invention. Figure 3 is a diagram of an example of the NR protocol architecture according to an embodiment of the present invention. The functions of each protocol described using Figure 2 and / or Figure 3 are some functions closely related to the embodiments of the present invention, and other functions may be present. In the embodiments of the present invention, the uplink (UL) may be a link from a terminal device to a base station device. In each embodiment of the present invention, the downlink (DL) may be a link from a base station device to a terminal device.

[0039] Figure 2(A) is a diagram of the E-UTRA user plane (UP) protocol stack. As shown in Figure 2(A), the E-UTRA UP protocol may be a protocol between UE122 and eNB102. That is, the E-UTRA UP protocol may be a protocol that terminates at eNB102 on the network side. As shown in Figure 2(A), the E-UTRA user plane protocol stack may consist of a radio physical layer (PHY) 200, a medium access control layer (MAC) 202, a radio link control layer (RLC) 204, and a packet data convergence protocol layer (PDCP) 206.

[0040] Figure 3(A) is a diagram of the NR user plane (UP) protocol stack. As shown in Figure 3(A), the NRUP protocol may be a protocol between UE122 and gNB108. That is, the NR UP protocol may be a protocol that terminates at gNB108 on the network side. As shown in Figure 3(A), the E-UTRA user plane protocol stack may consist of the wireless physical layer PHY300, the media access control layer MAC302, the wireless link control layer RLC304, the packet data convergence protocol layer PDCP306, and the service data adaptation protocol layer (service data adaptation protocol layer) SDAP (Service Data Adaptation Protocol)310.

[0041] Figure 2(B) shows the configuration of the E-UTRAN control plane (CP) protocol. As shown in Figure 2(B), in the E-UTRAN CP protocol, the Radio Resource Control (RRC) 208, which is the radio resource control layer, may be a protocol between the UE122 and the eNB102. That is, the RRC208 may be a protocol that terminates at the eNB102 on the network side. Also, in the E-UTRAN CP protocol, the Non Access Stratum (NAS) 210, which is the non-Access Stratum (AS) layer, may be a protocol between the UE122 and the MME. That is, the NAS210 may be a protocol that terminates at the MME on the network side.

[0042] Figure 3(B) is a diagram of the NR control plane (CP) protocol configuration. As shown in Figure 3(B), in the NR CP protocol, the RRC308, which is the radio resource control layer, may be the protocol between the UE122 and the gNB108. That is, the RRC308 may be a protocol that terminates at the gNB108 on the network side. Also, in the E-UTRAN CP protocol, the NAS312, which is a non-AS layer, may be the protocol between the UE122 and the AMF. That is, the NAS312 may be a protocol that terminates at the AMF on the network side.

[0043] The AS (Access Stratum) layer may be a layer that terminates between UE122 and eNB102 and / or gNB108. That is, the AS layer may be a layer containing some or all of PHY200, MAC202, RLC204, PDCP206, and RRC208, and / or a layer containing some or all of PHY300, MAC302, RLC304, PDCP306, SDAP310, and RRC308.

[0044] In the embodiments of the present invention, the E-UTRA protocol and the NR protocol are not distinguished below, and the terms PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), and NAS (NAS layer) may be used. In this case, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), and NAS (NAS layer) may be the PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), and NAS (NAS layer) of the E-UTRA protocol, respectively, or the PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), and NAS (NAS layer) of the NR protocol. Furthermore, SDAP (SDAP layer) may be the SDAP (SDAP layer) of the NR protocol.

[0045] Furthermore, in embodiments of the present invention, when distinguishing between the E-UTRA protocol and the NR protocol, PHY200, MAC202, RLC204, PDCP206, and RRC208 may be referred to as E-UTRA PHY or LTE PHY, E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA RRC or LTE RRC, respectively. Also, PHY200, MAC202, RLC204, PDCP206, and RRC208 may be described as E-UTRA PHY or LTE PHY, E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA RRC or LTE RRC, respectively. Furthermore, when distinguishing between the E-UTRA protocol and the NR protocol, PHY300, MAC302, RLC304, PDCP306, and RRC308 are sometimes referred to as NR PHY, NR MAC, NR RLC, NR RLC, and NR RRC, respectively. Also, PHY200, MAC302, RLC304, PDCP306, and RRC308 may be described as NR PHY, NR MAC, NR RLC, NR PDCP, and NR RRC, respectively.

[0046] This section describes entities in the AS layer of E-UTRA and / or NR. Entities that possess some or all of the functions of the MAC layer may be called MAC entities. Entities that possess some or all of the functions of the RLC layer may be called RLC entities. Entities that possess some or all of the functions of the PDCP layer may be called PDCP entities. Entities that possess some or all of the functions of the SDAP layer may be called SDAP entities. Entities that possess some or all of the functions of the RRC layer may be called RRC entities. MAC entities, RLC entities, PDCP entities, SDAP entities, and RRC entities may be replaced with MAC, RLC, PDCP, SDAP, and RRC, respectively.

[0047] Furthermore, the data provided from MAC, RLC, PDCP, and SDAP to lower layers, and / or the data provided from lower layers to MAC, RLC, PDCP, and SDAP, may be referred to as MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU, and SDAP PDU, respectively. Also, the data provided from higher layers to MAC, RLC, PDCP, and SDAP, and / or the data provided from MAC, RLC, PDCP, and SDAP to higher layers, may be referred to as MAC SDU (Service Data Unit), RLC SDU, PDCP SDU, and SDAP SDU, respectively. In addition, a segmented RLC SDU may be referred to as an RLC SDU segment.

[0048] An example of PHY functionality is described below. The terminal device's PHY may have the function of receiving data transmitted from the base station device's PHY via the Downlink (DL) physical channel. The terminal device's PHY may also have the function of transmitting data to the base station device's PHY via the Uplink (UL) physical channel. The PHY may be connected to a higher-level MAC via a Transport Channel. The PHY may transfer data to the MAC via the Transport Channel. The PHY may also receive data from the MAC via the Transport Channel. In the PHY, an RNTI (Radio Network Temporary Identifier) ​​may be used to identify various control information.

[0049] Now, let's discuss physical channels.

[0050] The following physical channels may be included in the physical channels used for wireless communication between terminal equipment and base station equipment.

[0051] PBCH (Physical Broadcast Channel) PDCCH (Physical Downlink Control Channel) PDSCH (Physical Downlink Shared Channel) PUCCH (Physical Uplink Control Channel) PUSCH (Physical Uplink Shared Channel) PRACH (Physical Random Access Channel)

[0052] PBCH may be used to broadcast system information required by terminal devices.

[0053] Furthermore, in NR, PBCH may be used to announce the time index (SSB-Index) within the period of a block of synchronization signals (SS / PBCH block, also called SSB).

[0054] PDCCH may be used in downlink wireless communication (wireless communication from base station equipment to terminal equipment) to transmit (or carry) Downlink Control Information (DCI). Here, one or more DCIs (which may be called DCI formats) may be defined for the transmission of downlink control information. That is, fields for downlink control information may be defined as DCIs and mapped to information bits. PDCCH may be transmitted in PDCCH candidates. Terminal equipment may monitor a set of PDCCH candidates in a serving cell. Monitoring a set of PDCCH candidates may mean attempting to decode a PDCCH according to a certain DCI format. The DCI format may be used for scheduling PUSCHs in a serving cell. PUSCHs may be used for transmitting user data or RRC messages, as described later.

[0055] PUCCH may be used to transmit Uplink Control Information (UCI) in uplink wireless communication (wireless communication from terminal equipment to base station equipment). Here, uplink control information may include channel state information (CSI) used to indicate the state of the downlink channel. Uplink control information may also include scheduling requests (SR) used to request UL-SCH (UL-SCH: Uplink Shared Channel) resources. Uplink control information may also include HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement).

[0056] PDSCH may be used to transmit downlink data (DL-SCH: Downlink Shared Channel) from the MAC layer. In the case of downlinks, it may also be used to transmit system information (SI: System Information) and random access responses (RAR: Random Access Response).

[0057] PUSCH may be used to transmit uplink data (UL-SCH: Uplink Shared Channel) from the MAC layer or HARQ-ACK and / or CSI along with uplink data. Alternatively, PUSCH may be used to transmit CSI only, or HARQ-ACK and CSI only. In other words, PUSCH may be used to transmit UCI only. Furthermore, PDSCH or PUSCH may be used to transmit RRC signaling (also called RRC messages) and MAC control elements. Here, in PDSCH, the RRC signaling transmitted from the base station equipment may be a common signaling for multiple terminal devices within a cell. Alternatively, the RRC signaling transmitted from the base station equipment may be dedicated signaling for a particular terminal device. In other words, UE-specific information may be transmitted using dedicated signaling for a particular terminal device. Furthermore, PUSCH may be used to transmit UE Capability on the uplink.

[0058] PRACH may be used to send a random access preamble. PRACH may also be used to indicate the initial connection establishment procedure, handover procedure, connection re-establishment procedure, synchronization (timing adjustment) for uplink transmissions, and PUSCH (UL-SCH) resource request.

[0059] Let's describe an example of MAC functionality. MAC can also be called a MAC sublayer.

[0060] A MAC may have the functionality to map various logical channels to corresponding transport channels. Logical channels may be identified by a Logical Channel Identity (Logical Channel ID). A MAC may be connected to a higher-level RLC via a logical channel. Logical channels may be divided into control channels that transmit control information and traffic channels that transmit user information, depending on the type of information being transmitted. Logical channels may also be divided into uplink logical channels and downlink logical channels. A MAC may have the functionality to multiplex MAC SDUs belonging to one or more different logical channels and provide them to the PHY. A MAC may also have the functionality to demultiplex MAC PDUs provided from the PHY and provide them to the higher layer via the logical channel to which each MAC SDU belongs.

[0061] MAC may also have a function to perform error correction through HARQ (Hybrid Automatic Repeat reQuest). MAC may also have a scheduling report (SR) function that reports scheduling information. MAC may have a function to perform priority processing between terminal devices using dynamic scheduling. MAC may also have a function to perform priority processing between logical channels within a single terminal device. MAC may also have a function to perform priority processing for overlapping resources within a single terminal device.

[0062] The E-UTRA MAC may have the functionality to identify Multimedia Broadcast Multicast Services (MBMS). The NR MAC may also have the functionality to identify Multicast Broadcast Services (MBS).

[0063] MAC may have the ability to select the transport format. MAC may also have the ability to perform discontinuous reception (DRX) and / or discontinuous transmission (DTX), the ability to perform random access (RA) procedures, a power headroom report (PHR) function to notify information on available power for transmission, a buffer status report (BSR) function to notify information on the amount of data in the transmit buffer, and so on.

[0064] NR MAC may have a Bandwidth Adaptation (BA) function. Furthermore, the MAC PDU format used in E-UTRA MAC and the MAC PDU format used in NR MAC may be different. Additionally, MAC PDU may include MAC control elements (MAC CE), which are elements for control within the MAC.

[0065] This document describes the logical channels used for uplink (UL) and / or downlink (DL) in E-UTRA and / or NR.

[0066] BCCH (Broadcast Control Channel) may be a downlink logical channel for broadcasting control information, such as system information (SI).

[0067] A PCCH (Paging Control Channel) may be a downlink logical channel for carrying paging messages.

[0068] A Common Control Channel (CCCH) may be a logical channel for transmitting control information between a terminal device and a base station device. A CCCH may be used when a terminal device does not have an RRC connection. A CCCH may also be used between a base station device and multiple terminal devices.

[0069] A DCCH (Dedicated Control Channel) may be a logical channel for transmitting dedicated control information in a point-to-point, bidirectional manner between a terminal device and a base station device. Dedicated control information may be control information specific to each terminal device. A DCCH may be used when the terminal device has an RRC connection.

[0070] A Dedicated Traffic Channel (DTCH) may be a logical channel for transmitting user data point-to-point between a terminal device and a base station device. A DTCH may be a logical channel for transmitting dedicated user data. Dedicated user data may be user data specific to each terminal device. A DTCH may exist on both the uplink and downlink.

[0071] A Multicast Traffic Channel (MTCH) may be a point-to-multipoint downlink channel for transmitting data from a base station to a terminal device. An MTCH may be a multicast logical channel. An MTCH may be used by a terminal device only when the terminal device receives MBMS.

[0072] An MCCH (Multicast Control Channel) may be a point-to-multipoint downlink channel for sending MBMS control information for one or more MTCHs from a base station device to a terminal device. An MCCH may be a multicast logical channel. An MCCH may be used by a terminal device only when the terminal device receives MBMS or is interested in receiving MBMS.

[0073] SC-MTCH (Single Cell Multicast Traffic Channel) may be a point-to-multipoint downlink channel for transmitting data from a base station to a terminal device using SC-PTM. SC-MTCH may be a multicast logical channel. SC-MTCH may be used by a terminal device only when the terminal device receives MBMS using SC-PTM (Single Cell Point-To-Multipoint).

[0074] SC-MCCH (Single Cell Multicast Control Channel) may be a point-to-multipoint downlink channel for sending MBMS control information for one or more SC-MCCHs from a base station device to a terminal device. SC-MCCH may be a multicast logical channel. SC-MCCH may be used by a terminal device only when the terminal device receives MBMS using SC-PTM, or when the terminal device is interested in receiving MBMS using SC-PTM.

[0075] This section describes the mapping between logical channels and transport channels for uplinks in E-UTRA and / or NR.

[0076] CCCH may be mapped to UL-SCH (Uplink Shared Channel), which is an uplink transport channel.

[0077] DCCH may be mapped to UL-SCH (Uplink Shared Channel), which is an uplink transport channel.

[0078] DTCH may be mapped to UL-SCH (Uplink Shared Channel), which is an uplink transport channel.

[0079] This section describes the mapping between logical channels and transport channels for downlinks in E-UTRA and / or NR.

[0080] BCCH may be mapped to a downlink transport channel, BCH (Broadcast Channel), and / or DL-SCH (Downlink Shared Channel).

[0081] The PCCH may be mapped to the PCH (Paging Channel), which is a downlink transport channel.

[0082] CCCH may be mapped to DL-SCH (Downlink Shared Channel), which is a downlink transport channel.

[0083] DCCH may be mapped to DL-SCH (Downlink Shared Channel), which is a downlink transport channel.

[0084] DTCH may be mapped to DL-SCH (Downlink Shared Channel), which is a downlink transport channel.

[0085] MTCH may be mapped to the downlink transport channel, which is the Multicast Channel (MCH).

[0086] MCCH may be mapped to MCH (Multicast Channel), which is a downlink transport channel.

[0087] SC-MTCH may be mapped to DL-SCH (Downlink Shared Channel), which is a downlink transport channel.

[0088] SC-MTCH may be mapped to DL-SCH (Downlink Shared Channel), which is a downlink transport channel.

[0089] Let's describe an example of RLC functionality. RLC can also be called an RLC sublayer.

[0090] E-UTRA RLC may have the functionality to segment and / or concatenate data provided from the upper layer PDCP and provide it to the lower layer. E-UTRA RLC may also have the functionality to reassemble and reorder data provided from the lower layer and provide it to the upper layer.

[0091] NR RLC may have the function of adding a sequence number to the data provided by the upper-layer PDCP that is independent of the sequence number added by the PDCP. NR RLC may also have the function of segmenting the data provided by the PDCP and providing it to the lower layer. Furthermore, NR RLC may have the function of reassembling the data provided by the lower layer and providing it to the upper layer. RLC may also have a data retransmission function and / or an automatic repeat request (ARQ) function.

[0092] RLC may also have a function to perform error correction using ARQ. The control information sent from the receiver to the transmitter of the RLC, indicating data that needs to be retransmitted, for the purpose of performing ARQ, may be called a status report. The instruction to send a status report, sent from the transmitter to the receiver of the RLC, may be called a poll. RLC may also have a function to detect data duplication. RLC may also have a function to discard data.

[0093] RLC may have three modes: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). In TM mode, data received from the upper layer is not split, and an RLC header does not need to be added. A TM RLC entity is a unidirectional entity and may be configured as a transmitting TM RLC entity or a receiving TM RLC entity. In UM mode, data received from the upper layer is split and / or combined, an RLC header is added, etc., but data retransmission control does not need to be performed. A UM RLC entity may be a unidirectional entity or a bidirectional entity. If a UM RLC entity is a unidirectional entity, it may be configured as a transmitting UM RLC entity or a receiving UM RLC entity. If a UM RLC entity is a bidirectional entity, it may be configured as a UM RLC entity consisting of a transmitting side and a receiving side. AM may perform operations such as splitting and / or combining data received from higher layers, adding RLC headers, and controlling data retransmission. AM RLC entities are bidirectional entities and may be configured as AM RLC consisting of a transmitting side and a receiving side. Data provided to lower layers by TM, and / or data provided from lower layers, may be called TMD PDUs. Similarly, data provided to lower layers by UM, and / or data provided from lower layers, may be called UMD PDUs. Furthermore, data provided to lower layers by AM, or data provided from lower layers, may be called AMD PDUs.

[0094] The RLC PDU format used in E-UTRA RLC and the RLC PDU format used in NR RLC may be different. Furthermore, there may be data RLC PDUs and control RLC PDUs. The data RLC PDU may be called an RLC DATA PDU (RLC Data PDU). The control RLC PDU may be called an RLC CONTROL PDU (RLC Control PDU).

[0095] Let's describe an example of PDCP functionality. PDCP can be referred to as a PDCP sublayer.

[0096] PDCP may have a function for maintaining sequence numbers. PDCP may also have a header compression / decompression function for efficiently transmitting user data such as IP packets and Ethernet frames over the wireless section. The protocol used for compressing and decompressing IP packet headers may be called the ROHC (Robust Header Compression) protocol. The protocol used for compressing and decompressing Ethernet frame headers may be called the EHC (Ethernet® Header Compression) protocol. PDCP may also have a data encryption / decryption function. PDCP may also have a data integrity protection / integrity verification function. PDCP may also have a re-ordering function. PDCP may also have a PDCP SDU retransmission function. PDCP may also have a data discard function using a discard timer. PDCP may also have a duplication function. PDCP may also have a function to discard duplicate received data.

[0097] A PDCP entity is a bidirectional entity and may consist of a transmitting PDCP entity and a receiving PDCP entity. The PDCP PDU format used in E-UTRA PDCP and the PDCP PDU format used in NR PDCP may be different. Furthermore, there may be data PDCP PDUs and control PDCP PDUs. The data PDCP PDU may be called a PDCP DATA PDU (PDCP Data PDU). The control PDCP PDU may be called a PDCP CONTROL PDU (PDCP Control PDU).

[0098] This section describes an example of SDAP functionality. SDAP is a Service Data Adaptive Protocol Layer (SAP).

[0099] SDAP may have the function of mapping downlink QoS flows sent from 5GC110 to terminal devices via base station equipment to data radio bearers (DRBs), and / or mapping uplink QoS flows sent from terminal devices to 5GC110 via base station equipment to DRBs. SDAP may also have the function of storing mapping rule information. SDAP may also have the function of marking QoS flow identifiers (QoS Flow ID: QFI). Note that there may be data SDAP PDUs and control SDAP PDUs. Data SDAP PDUs may be called SDAP DATA PDUs (SDAP Data PDUs). Control SDAP PDUs may be called SDAP CONTROL PDUs (SDAP Control PDUs). Note that there may be one SDAP entity for each PDU session in a terminal device.

[0100] This section describes an example of RRC's functionality.

[0101] The RRC may have a broadcast function. The RRC may have a paging function from EPC104 and / or 5GC110. The RRC may have a paging function from eNB102 connected to gNB108 or 5GC100. The RRC may also have an RRC connection management function. The RRC may also have a wireless bearer control function. The RRC may also have a cell group control function. The RRC may also have a mobility control function. The RRC may also have terminal device measurement reporting and terminal device measurement reporting control functions. The RRC may also have a QoS management function. The RRC may also have a wireless link failure detection and recovery function. The RRC may use RRC messages to perform broadcasting, paging, RRC connection management, wireless bearer control, cell group control, mobility control, terminal device measurement reporting and terminal device measurement reporting control, QoS management, wireless link failure detection and recovery, etc. Note that the RRC messages and parameters used in E-UTRA RRC may differ from those used in NR RRC.

[0102] RRC messages may be sent using the logical channels BCCH, PCCH, CCCH, DCCH, or MCCH.

[0103] RRC messages sent using BCCH may include, for example, a Master Information Block (MIB), a System Information Block (SIB) of each type, or other RRC messages. RRC messages sent using PCCH may include, for example, a paging message or other RRC messages.

[0104] RRC messages sent in the uplink (UL) direction using CCCH may include, for example, RRC Setup Request, RRC Resume Request, RRC Reestablishment Request, and RRC System Info Request. They may also include, for example, RRC Connection Request, RRC Connection Resume Request, and RRC Connection Reestablishment Request. Other RRC messages may also be included.

[0105] RRC messages sent in the downlink (DL) direction using CCCH may include, for example, RRC Connection Reject messages, RRC Connection Setup messages, RRC Connection Reestablishment messages, and RRC Connection Reestablishment Reject messages. They may also include, for example, RRC Reject messages and RRC Setup messages. Other RRC messages may also be included.

[0106] RRC messages sent in the uplink (UL) direction using DCCH may include, for example, a Measurement Report message, an RRC Connection Reconfiguration Complete message, an RRC Connection Setup Complete message, an RRC Connection Reestablishment Complete message, a Security Mode Complete message, and an UE Capability Information message. They may also include, for example, a Measurement Report message, an RRC Reconfiguration Complete message, an RRC Setup Complete message, an RRC Reestablishment Complete message, an RRC Resume Complete message, a Security Mode Complete message, and an UE Capability Information message. Other RRC messages may also be included.

[0107] RRC messages sent in the downlink (DL) direction using DCCH may include, for example, RRC Connection Reconfiguration messages, RRC Connection Release messages, Security Mode Command messages, and UE Capability Enquiry messages. They may also include, for example, RRC Reconfiguration messages, RRC Resume messages, RRC Release messages, RRC Reestablishment messages, Security Mode Command messages, and UE Capability Enquiry messages. Other RRC messages may also be included.

[0108] This section describes some examples of NAS functionality. A NAS may have authentication capabilities. It may also have mobility management capabilities. Furthermore, a NAS may have security control capabilities.

[0109] The aforementioned PHY, MAC, RLC, PDCP, SDAP, RRC, and NAS functions are merely examples, and some or all of each function may not be implemented. Furthermore, some or all of the functions of each layer may be included in other layers.

[0110] Furthermore, the layers above the AS layer of the terminal device (not shown) may include the IP layer, and above the IP layer, the TCP (Transmission Control Protocol) layer, UDP (User Datagram Protocol) layer, etc. The Ethernet layer may also exist above the AS layer of the terminal device. This layer above the AS layer of the terminal device may be called the PDU layer. The PDU layer may include the IP layer, TCP layer, UDP layer, Ethernet layer, etc. Above the IP layer, TCP layer, UDP layer, Ethernet layer, PDU layer, etc., there may be an application layer. The application layer may include SIP (Session Initiation Protocol) and SDP (Session Description Protocol), which are used in IMS (IP Multimedia Subsystem), one of the service networks standardized by 3GPP. The application layer may also include RTP (Real-time Transport Protocol), used for media communication, and / or protocols such as RTCP (Real-time Transport Control Protocol) and HTTP (HyperText Transfer Protocol) for media communication control. The application layer may also include codecs for various media. Furthermore, the RRC layer may be a higher layer than the SDAP layer.

[0111] Next, we will explain the states and state transitions of UE122 in LTE and NR.

[0112] A UE122 connected to an EPC or 5GC may be in the RRC_CONNECTED state when an RRC connection has been established. The state in which an RRC connection has been established may include a state in which the UE122 holds some or all of the UE context described below. The state in which an RRC connection has been established may also include a state in which the UE122 can send and / or receive unicast data. Furthermore, a UE122 may be in the RRC_INACTIVE state when the RRC connection is suspended. A UE122 may be in the RRC_INACTIVE state when it is connected to a 5GC and the RRC connection is suspended. When a UE122 is neither in the RRC_CONNECTED state nor the RRC_INACTIVE state, the UE122 may be in the RRC_IDLE state.

[0113] Note that if UE122 is connected to EPC, it does not have the RRC_INACTIVE state, but E-UTRAN may initiate the suspension of the RRC connection. When UE122 is connected to EPC and the RRC connection is suspended, UE122 may transition to the RRC_IDLE state, retaining the UE's AS context and the identifier (resumeIdentity) used for resuming. The upper layer of the UE122's RRC layer (e.g., the NAS layer) may initiate the resumption of the suspended RRC connection if UE122 retains the UE's AS context, E-UTRAN has permitted the resumption of the RRC connection, and UE122 needs to transition from the RRC_IDLE state to the RRC_CONNECTED state.

[0114] The definition of RRC connection pause may differ between UE122 connected to EPC104 and UE122 connected to 5GC110. Furthermore, all or part of the procedure for UE122 to resume from RRC connection pause may differ depending on whether UE122 is connected to EPC (paused in RRC_IDLE state) or UE122 is connected to 5GC (paused in RRC_INACTIVE state).

[0115] The RRC_CONNECTED state, RRC_INACTIVE state, and RRC_IDLE state may be referred to as RRC connected mode, RRC inactive mode, and RRC idle mode, respectively. If there is no risk of misinterpretation, they may simply be referred to as connected mode, inactive mode, and idle mode.

[0116] The AS context of the UE held by UE122 may include all or part of the following information: the current RRC settings, the current security context, the PDCP status including the ROHC (RObust Header Compression) status, the C-RNTI (Cell Radio Network Temporary Identifier) ​​used by the source PCell, the cell identifier, and the physical cell identifier of the source PCell. The AS context of the UE held by any or all of eNB102 and gNB108 may include the same information as the AS context of the UE held by UE122, or it may include information different from the information included in the AS context of the UE held by UE122.

[0117] The security context may include all or part of the following at the AS level: the encryption key, the NH (Next Hop parameter), the NCC (Next Hop Chaining Counter parameter) used to derive the next hop access key, the identifier of the selected AS-level encryption algorithm, and the counter used for replay protection.

[0118] This section describes cell groups configured by the base station equipment for terminal equipment. A cell group may consist of only one special cell (SpCell). Alternatively, a cell group may consist of one SpCell and one or more secondary cells (SCells). In other words, a cell group may consist of one SpCell and, optionally, one or more SCells. When a MAC entity is associated with a master cell group (MCG), SpCell may mean a primary cell (PCell). When a MAC entity is associated with a secondary cell group (SCG), SpCell may mean a primary SCG cell (PSCell). When a MAC entity is not associated with a cell group, SpCell may mean a PCell. PCell, PSCell, and SCell are serving cells. SpCell may support PUCCH transmission and contention-based random access. SpCell may always be in an activated state. PCell may be a cell used in the RRC connection establishment procedure when a terminal device in an RRC idle state transitions to an RRC connected state. PCell may also be a cell used in the RRC connection re-establishment procedure when a terminal device re-establishes an RRC connection. PCell may also be a cell used in the random access procedure during handover. PSCell may be a cell used in the random access procedure when adding a secondary node (SN), as described later. SpCell may also be a cell used for purposes other than those described above. Note that if a cell group consists of a SpCell and one or more SCells, it can be said that carrier aggregation (CA) is set up for this cell group.Furthermore, for terminal devices where CA is configured, a cell that provides additional radio resources to a SpCell may be considered an SCell.

[0119] A group of serving cells configured by RRC that uses the same timing reference cell and the same timing advance value for cells with uplinks configured within that group may be called a Timing Advance Group (TAG). Furthermore, a TAG containing a MAC entity SpCell may represent a Primary Timing Advance Group (PTAG). In addition, a TAG other than a PTAG may represent a Secondary Timing Advance Group (STAG).

[0120] Furthermore, when Dual Connectivity (DC) or Multi-Radio Dual Connectivity (MR-DC) is implemented, cell groups may be added from the base station equipment to terminal equipment. DC is a technology that uses the radio resources of cell groups configured by a first base station equipment (first node) and a second base station equipment (second node) to perform data communication. MR-DC is a technology included in DC. In order to perform DC, the first base station equipment may add a second base station equipment. The first base station equipment may be called the Master Node (MN). The cell group configured by the master node may be called the Master Cell Group (MCG). The second base station equipment may be called the Secondary Node (SN). The cell group configured by the secondary node may be called the Secondary Cell Group (SCG). Note that the master node and secondary node may be configured within the same base station equipment.

[0121] Furthermore, when a DC is not configured, the cell group configured on the terminal device may be called an MCG. Also, when a DC is not configured, the SpCell configured on the terminal device may be a PCell.

[0122] Furthermore, MR-DC may be a technology that performs DC using E-UTRA for MCG and NR for SCG. Also, MR-DC may be a technology that performs DC using NR for MCG and E-UTRA for SCG. Also, MR-DC may be a technology that performs DC using NR for both MCG and SCG. Examples of MR-DC using E-UTRA for MCG and NR for SCG include EN-DC (E-UTRA-NR Dual Connectivity) using EPC for the core network, and NGEN-DC (NG-RAN E-UTRA-NR Dual Connectivity) using 5GC for the core network. Also, an example of MR-DC using NR for MCG and E-UTRA for SCG is NE-DC (NR-E-UTRA Dual Connectivity) using 5GC for the core network. Also, an example of MR-DC using NR for MCG and E-UTRA for SCG is NR-DC (NR-NR Dual Connectivity) using 5GC for the core network.

[0123] In a terminal device, there may be one MAC entity for each cell group. For example, when a DC or MR-DC is configured on a terminal device, there may be one MAC entity for the MCG and one MAC entity for the SCG. The MAC entity for the MCG on a terminal device may always be established in all states of the terminal device (RRC idle state, RRC connected state, and RRC inactive state, etc.). The MAC entity for the SCG on a terminal device may be created by the terminal device when the SCG is configured on the terminal device. The MAC entities for each cell group on a terminal device may be established when the terminal device receives an RRC message from the base station device. In EN-DC and NGEN-DC, the MAC entity for the MCG may be an E-UTRA MAC entity, and the MAC entity for the SCG may be an NR MAC entity. In NE-DC, the MAC entity for the MCG may be an NR MAC entity, and the MAC entity for the SCG may be an E-UTRA MAC entity. In NR-DC, both the MAC entities for the MCG and SCG may be NR MAC entities. Furthermore, the statement that there is one MAC entity for each cell group can be rephrased as "there is one MAC entity for each SpCell." Similarly, the statement that there is one MAC entity for each cell group can be rephrased as "there is one MAC entity for each SpCell."

[0124] Let's explain wireless bearers. For E-UTRA, SRB0 through SRB2 may be defined, or other SRBs may be defined. For NR, SRB0 through SRB3 may be defined, or other SRBs may be defined.

[0125] SRB0 may be an SRB for RRC messages, which is transmitted and / or received using the logical channel CCCH.

[0126] SRB1 may be an SRB for RRC messages and for NAS messages before SRB2 is established. RRC messages transmitted and / or received using SRB1 may include piggybacked NAS messages. All RRC and NAS messages transmitted and / or received using SRB1 may use the DCCH logical channel.

[0127] SRB2 may be an SRB for NAS messages and for RRC messages containing logged measurement information. All RRC and NAS messages transmitted and / or received using SRB2 may use the logical channel DCCH. Furthermore, SRB2 may have a lower priority than SRB1.

[0128] SRB3 may be an SRB for transmitting and / or receiving specific RRC messages when EN-DC, NGEN-DC, NR-DC, etc., are configured on the terminal device. All RRC and NAS messages transmitted and / or received using SRB3 may use the logical channel DCCH. Other SRBs may be provided for other purposes. DRB may be a wireless bearer for user data. RRC messages transmitted and / or received using DRB may use the logical channel DTCH.

[0129] This section describes a wireless bearer in a terminal device. The wireless bearer may include an RLC bearer. An RLC bearer may consist of one or two RLC entities and a logical channel. If there are two RLC entities in an RLC bearer, the RLC entities may be a TM RLC entity and / or a transmit RLC entity and a receive RLC entity in a unidirectional UM mode RLC entity.

[0130] SRB0 may consist of one RLC bearer. The RLC bearer of SRB0 may consist of a TM RLC entity and a logical channel. SRB0 may always be established in terminal devices in all states (RRC idle state, RRC connected state, and RRC inactive state, etc.). SRB1 may be established and / or set on a terminal device by an RRC message received from the base station device when the terminal device transitions from the RRC idle state to the RRC connected state. SRB1 may consist of one PDCP entity and one or more RLC bearers. The RLC bearer of SRB1 may consist of an AM RLC entity and a logical channel. SRB2 may be established and / or set on a terminal device by an RRC message received from the base station device when the terminal device is in the RRC connected state with AS security activated. SRB2 may consist of one PDCP entity and one or more RLC bearers. The RLC bearer of SRB2 may consist of an AM RLC entity and a logical channel. The PDCP on the base station equipment side of SRB1 and SRB2 may be located on the master node. SRB3 may be established and / or configured on a terminal device when a secondary node is added to or changed in EN-DC, NGEN-DC, or NR-DC, by an RRC message received from the base station equipment by a terminal device in an RRC connection state with AS security activated. SRB3 may be a direct SRB between the terminal device and the secondary node. SRB3 may consist of one PDCP entity and one or more RLC bearers. The RLC bearers of SRB3 may consist of an AM RLC entity and a logical channel. The PDCP on the base station equipment side of SRB3 may be located on the secondary node.

[0131] One or more DRBs may be established and / or configured on a terminal device by RRC messages received from a base station device by a terminal device in an RRC connection state with AS security activated. A DRB may consist of one PDCP entity and one or more RLC bearers. The RLC bearers of a DRB may consist of AM or UM RLC entities and logical channels.

[0132] In MR-DC, a wireless bearer with a PDCP on the master node may be called an MN-terminated bearer. Similarly, a wireless bearer with a PDCP on the secondary node may be called an SN-terminated bearer. Furthermore, in MR-DC, a wireless bearer with an RLC bearer present only in the MCG may be called an MCG bearer. Similarly, a wireless bearer with an RLC bearer present only in the SCG may be called an SCG bearer. Finally, in a DC, a wireless bearer with an RLC bearer present in both the MCG and SCG may be called a split bearer.

[0133] When MR-DC is configured on a terminal device, the bearer types of SRB1 and SRB2 established and / or configured on the terminal device may be MN-terminated MCG bearers and / or MN-terminated split bearers. Also, when MR-DC is configured on a terminal device, the bearer type of SRB3 established and / or configured on the terminal device may be SN-terminated SCG bearers. Also, when MR-DC is configured on a terminal device, the bearer type of DRB established and / or configured on the terminal device may be any of all bearer types.

[0134] For RLC bearers established and / or configured in a cell group composed of E-UTRA, the established and / or configured RLC entities may be E-UTRA RLC. Similarly, for RLC bearers established and / or configured in a cell group composed of NR, the established and / or configured RLC entities may be NR RLC. When EN-DC is configured on a terminal device, the PDCP entities established and / or configured for MN-terminated MCG bearers may be either E-UTRA PDCP or NR PDCP. Furthermore, when EN-DC is configured on a terminal device, the PDCP established and / or configured for other bearer types of wireless bearers, namely MN-terminated split bearers, MN-terminated SCG bearers, SN-terminated MCG bearers, SN-terminated split bearers, and SN-terminated SCG bearers, may be NR PDCP. Additionally, when NGEN-DC, NE-DC, or NR-DC is configured on a terminal device, the PDCP entities established and / or configured for wireless bearers of all bearer types may be NR PDCP.

[0135] In NR, the DRB established and / or configured on the terminal device may be associated with one PDU session. One SDAP entity may be established and / or configured for one PDU session on the terminal device. The SDAP entities, PDCP entities, RLC entities, and logical channels established and / or configured on the terminal device may be established and / or configured by RRC messages received by the terminal device from the base station device.

[0136] Regardless of whether MR-DC is configured or not, a network configuration with eNB102 as the master node and EPC104 as the core network may be called E-UTRA / EPC. Similarly, a network configuration with eNB102 as the master node and 5GC110 as the core network may be called E-UTRA / 5GC. Furthermore, a network configuration with gNB108 as the master node and 5GC110 as the core network may be called NR, or NR / 5GC. When MR-DC is not configured, the master node mentioned above may refer to the base station equipment that communicates with terminal devices.

[0137] Next, we will explain handover in LTE and NR. Handover may be the process by which UE122 in an RRC connection state changes the serving cell. Handover may occur when UE122 receives an RRC message instructing a handover from eNB102 and / or gNB108. An RRC message instructing a handover may be a message concerning the reconfiguration of the RRC connection that includes a parameter instructing a handover (for example, an information element named MobilityControlInfo or an information element named ReconfigurationWithSync). The information element named MobilityControlInfo may be rephrased as a mobility control setting information element, mobility control setting, or mobility control information. The information element named ReconfigurationWithSync may be rephrased as a synchronized reconfiguration information element, or synchronized reconfiguration. Furthermore, an RRC message instructing a handover may be a message indicating movement to another RAT's cell (for example, MobilityFromEUTRACommand or MobilityFromNRCommand). The term "handover" may also be rephrased as "reconfiguration with sync." Furthermore, the conditions under which UE122 can perform a handover may include some or all of the following: AS security is activated, SRB2 is established, and at least one DRB is established.

[0138] Furthermore, the terminal device may perform a process that does not change the serving cell based on the RRC message instructing a handover. In other words, the terminal device may perform a handover process with the same cell as the current serving cell as the target cell.

[0139] The flow of RRC messages transmitted and received between a terminal device and a base station device is described below. Figure 4 is a diagram showing an example of the flow of procedures for various settings in RRC according to an embodiment of the present invention. Figure 4 is an example of the flow when an RRC message is sent from a base station device (eNB102, and / or gNB108) to a terminal device (UE122).

[0140] In Figure 4, the base station device creates an RRC message (step S400). The creation of an RRC message by the base station device may be performed in order for the base station device to distribute broadcast information (SI: System Information) or paging information. The creation of an RRC message by the base station device may also be performed in order for the base station device to have a specific terminal device perform a process. The process to be performed by a specific terminal device may include, for example, security settings, RRC connection reconfiguration, handover to a different RAT, suspension of RRC connection, and release of RRC connection. RRC connection reconfiguration processes may include, for example, control of radio bearers (establish, change, release, etc.), control of cell groups (establish, add, change, release, etc.), measurement settings, handover, security key update, etc. The creation of an RRC message by the base station device may also be performed in order to respond to an RRC message sent from a terminal device. Responses to RRC messages sent from a terminal device may include, for example, responses to RRC setup requests, responses to RRC reconnection requests, and responses to RRC restart requests. RRC messages contain various information notifications and configuration information (parameters). These parameters may be called fields and / or information elements and may be described using the ASN.1 (Abstract Syntax Notation One) notation scheme.

[0141] In Figure 4, the base station device then transmits the created RRC message to the terminal device (step S402). The terminal device then performs any necessary processing, such as configuration, according to the received RRC message (step S404). The terminal device that has performed the processing may send a response RRC message to the base station device (not shown).

[0142] RRC messages may be used for purposes other than those mentioned above.

[0143] In MR-DC, the RRC on the master node side may be used to transfer RRC messages for SCG side settings (cell group settings, wireless bearer settings, measurement settings, etc.) to and from terminal devices. For example, in EN-DC or NGEN-DC, the RRC message for E-UTRA transmitted and received between eNB102 and UE122 may contain the RRC message for NR in the form of a container. Similarly, in NE-DC, the RRC message for NR transmitted and received between gNB108 and UE122 may contain the RRC message for E-UTRA in the form of a container. RRC messages for SCG side settings may be transmitted and received between the master node and secondary nodes.

[0144] Furthermore, not only when using MR-DC, the RRC message for E-UTRA sent from eNB102 to UE122 may include an RRC message for NR, and the RRC message for NR sent from gNB108 to UE122 may include an RRC message for E-UTRA.

[0145] This section describes an example of parameters included in an RRC message regarding RRC connection reconfiguration. Figure 7 is an example of an ASN.1 description representing a field and / or information element related to the radio bearer setting included in a message regarding RRC connection reconfiguration in NR, as shown in Figure 4. Figure 8 is also an example of an ASN.1 description representing a field and / or information element related to the radio bearer setting included in a message regarding RRC connection reconfiguration in E-UTRA, as shown in Figure 4. In the examples of ASN.1 in embodiments of the present invention, not limited to Figures 7 and 8, <omitted> and <omitted> indicate that other information is omitted, not part of the ASN.1 notation. Information elements may also be omitted where there is no <omitted> or <omitted> notation. Note that the examples of ASN.1 in embodiments of the present invention do not strictly follow the ASN.1 notation method. The examples of ASN.1 in embodiments of the present invention are examples of parameters in an RRC message in embodiments of the present invention, and other names or notations may be used. Furthermore, to avoid making the explanation complicated, only examples of main information closely related to one embodiment of the present invention are shown. In addition, parameters described in ASN.1 are sometimes referred to as "information elements" without distinguishing between fields, information elements, etc. Also, in embodiments of the present invention, fields, information elements, etc. described in ASN.1 included in the RRC message may be referred to as "information" or as "parameters." The message relating to the resetting of the RRC connection may be an RRC reset message in NR or an RRC connection reset message in E-UTRA.

[0146] This section describes cell activation and deactivation. In terminal devices communicating via dual connectivity, the master cell group (MCG) and secondary cell group (SCG) are configured by the message regarding the reconfiguration of the RRC connection mentioned above. Each cell group may consist of a special cell (SpCell) and zero or more other cells (secondary cells: SCell). The SpCell of the MCG is also called a PCell. The SpCell of the SCG is also called a PSCell. Cell deactivation does not apply to SpCells, but may apply to SCells.

[0147] Furthermore, cell deactivation may not be applied to PCell but may be applied to PSCell. In this case, the cell deactivation process may differ between SpCell and SCell.

[0148] Cell activation and deactivation may be handled by MAC entities present in each cell group. SCells configured on a terminal device may be activated and / or deactivated by (A), (B), and / or (C) below. (A) Reception of MAC CE indicating SCell activation / inactivation (B) A SCell deactivation timer is set for each SCell that does not have PUCCH configured (the SCell is deactivated when the timer expires). (C) SCell state (sCellState) is set for each SCell by the RRC message (SCells are activated based on the fact that the SCell configuration includes a field for SCell state).

[0149] Specifically, the MAC entity of the terminal device may perform some or all of the following processes (AD) for each SCell configured in the cell group.

[0150] (Processing AD) (1) If the RRC parameter (SCell state) is set to activated when the SCell is set, or if a MAC CE that activates the SCell is received, the MAC entity of UE122 performs action (AD-1). Otherwise, if a MAC CE that deactivates the SCell is received, or if the SCell deactivation timer expires for an activated SCell, the MAC entity of UE122 performs action (AD-2). (2) If an uplink grant or downlink assignment is notified by the PDCCH of an active SCell, or if an uplink grant or downlink assignment is notified by the PDCCH of a serving cell for an active SCell, or if a MAC PDU is sent for a configured uplink grant, or if a MAC PDU is received for a configured downlink assignment, the MAC entity of UE122 restarts the SCell inactive timer associated with that SCell. (3) If SCell becomes inactive, the MAC entity of UE122 performs the action (AD-3).

[0151] (Process AD-1) The MAC entity of the terminal device may perform some or all of the following (1) to (3): (1) If, in NR, this SCell was inactive before receiving a MAC CE to activate it, or if the RRC parameter (sCellState) set for that SCell during SCell configuration was set to activated, the MAC entity of UE122 performs processing (AD-1-1). (2) The MAC entity of UE122 starts or restarts the SCell deactivation timer associated with its SCell (if it has already started). (3) If the Active DL BWP is not a Dormant BWP, and there is a suspended Type 1 configured uplink grant associated with this SCell according to the stored configuration, the MAC entity of UE122 will (re)initialize it. The MAC entity of UE122 will then trigger a PHR.

[0152] (Process AD-1-1) The MAC entity of the terminal device may perform some or all of the following (1) to (3): (1) If the BWP indicated by the first Active Downlink BWP-Id set in the RRC message for that SCell is not set as a Dormant BWP, the MAC entity of UE122 performs processing (AD-1-1-1). (2) If the BWP indicated by the first Active Downlink BWP-Id set in the RRC message for that SCell is set to Dormant BWP, the MAC entity of UE122 stops the BWP Inactivity Timer (bwp-InactivityTimer) for this serving cell, if it is running. (3) The MAC entity of UE122 activates the downlink BWP indicated by the first active downlink BWP identifier (firstActiveDownlinkBWP-Id) and the uplink BWP indicated by the first active uplink BWP identifier (firstActiveUplinkBWP-Id), which are set in the RRC message for its SCell.

[0153] (Process AD-1-1-1) The MAC entity of the terminal device may activate SCell at a predetermined time and apply (perform) normal SCell operations, including some or all of the following (A) through (E). (A) Transmission of sounding reference signal (SRS) in this SCell (B) Reporting of channel status information (CSI) for this SCell (C) Monitoring of PDCCH in this SCell (D) Monitoring of PDCCH for this SCell (if scheduling is performed for this SCell in other serving cells) (E) If PUCCH is set, PUCCH transmission in this SCell

[0154] (Process AD-2) The MAC entity of the terminal device may perform some or all of the following (A) through (D): (A) Deactivate this SCell at the default timing. (B) Stop the SCell deactivation timer associated with this SCell. (C) Deactivate all Active BWPs associated with this SCell. (D) Flushes the HARQ buffer associated with this SCell.

[0155] (Process AD-3) The MAC entity of the terminal device may perform some or all of the following (A) through (D): (A) Do not send SRS with this SCell. (B) Do not report a CSI for this SCell. (C) Do not send PUCCH, UL-SCH, and / or RACH with this SCell. (D) Do not monitor the PDCCH of this SCell, and / or the PDCCH for this SCell.

[0156] As described above, the MAC entity performs processing (AD) to activate and deactivate SCells.

[0157] Furthermore, as mentioned above, when a SCell is added, its initial state may be set by an RRC message.

[0158] Here, we will explain the SCell deactivation timer. For SCells for which PUCCH is not set, the value of the SCell deactivation timer (information about the time at which the timer is considered to have expired) may be notified by an RRC message. For example, if the RRC message notifies that the value of the SCell deactivation timer is 40ms, then in the above process (AD), the timer will be considered to have expired when the notified time (40ms in this case) has elapsed since the timer was started or restarted without the timer stopping. The SCell deactivation timer may also be named a timer called sCellDeactivationTimer.

[0159] Now, let's explain the bandwidth portion (BWP).

[0160] A BWP may be part or all of the bandwidth of a serving cell. A BWP may also be called a Carrier BWP. One or more BWPs may be configured on a terminal device. A BWP may be configured by information contained in broadcast information associated with a synchronization signal detected in the initial cell search. Another BWP may be a frequency bandwidth associated with the frequency at which the initial cell search is performed. Another BWP may be configured by RRC signaling (e.g., Dedicated RRC signaling). Downlink BWPs (DL BWPs) and uplink BWPs (UL BWPs) may be configured separately. One or more uplink BWPs may be associated with one or more downlink BWPs. Furthermore, the mapping between the uplink BWP and the downlink BWP may be a default mapping, a mapping by RRC signaling (e.g., Dedicated RRC signaling), a mapping by physical layer signaling (e.g., downlink control information (DCI) notified via the downlink control channel), or a combination of these.

[0161] A BWP may consist of a group of consecutive Physical Resource Blocks (PRBs). Furthermore, parameters for one or more BWPs of each component carrier may be set for a connected terminal device. The BWP parameters for each component carrier may include some or all of the following: (A) the type of cyclic prefix, (B) the subcarrier spacing, (C) the frequency position of the BWP (e.g., the starting position or central frequency position on the lower frequency side of the BWP) (the frequency position may be, for example, an ARFCN or an offset from a specific subcarrier of the serving cell. The unit of the offset may be in subcarrier units or resource block units. Both ARFCN and offset may be set.), (D) the bandwidth of the BWP (e.g., the number of PRBs), (E) resource configuration information for the control signals, and (F) the center frequency position of the SS block (the frequency position may be, for example, an ARFCN or an offset from a specific subcarrier of the serving cell. The unit of the offset may be in subcarrier units or resource block units. Both ARFCN and offset may be set.). Additionally, resource configuration information for the control signals may be included in the BWP settings for at least some or all of the PCell and / or PSCell.

[0162] A terminal device may transmit and receive data using the active BWP (Active BWP) among one or more configured BWPs. A terminal device may be configured such that, at any given time, a maximum of one uplink BWP and / or one downlink BWP among the one or more BWPs configured for a single serving cell associated with it are active. An activated downlink BWP is also referred to as an Active DL BWP. An activated uplink BWP is also referred to as an Active UL BWP.

[0163] Next, we will explain BWP deactivation. One or more BWPs may be set in a single serving cell. BWP switching in a serving cell is used to activate an inactive BWP (also called an inactive BWP) and deactivate an activated BWP.

[0164] BWP switching is controlled by the MAC entity itself for a PDCCH indicating downlink allocation or uplink grant, a BWP inactivity timer, RRC signaling, or the initiation of a random access procedure. The active BWP of a serving cell is indicated by the RRC or PDCCH.

[0165] Next, we will explain dormant BWPs. Entering or leaving a dormant BWP is done by switching BWPs. This control is performed by PDCCH for each SCell or for groups called Dormancy SCell Groups. The setting of dormant SCell Groups is indicated by RRC signaling. Also, in the current specification, dormant BWPs apply only to SCells. It should be understood that a dormant BWP is not a BWP that is changed into a dormant state, but rather one BWP set for dormancy among one or more BWPs set for the UE. Furthermore, there may be multiple BWPs set for dormancy on the UE.

[0166] A BWP may be dormant if its configuration does not include certain parameters. For example, a BWP may be dormant if it does not include the PDCCH-Config information element, which is an information element for setting UE-specific PDCCH parameters included in the configuration of a downlink BWP. Alternatively, a BWP may be dormant if some of the parameters included in the PDCCH-Config information element, which is an information element for setting UE-specific PDCCH parameters included in the configuration of a downlink BWP, are not set (not included). For example, a BWP may be dormant if its configuration does not include some or all of the settings for the search space, which are set by the PDCCH-Config information element and define where and / or how to search for PDCCH candidates.

[0167] Additionally, in certain settings, the setting of a dormant BWP for SpCells such as PCell and PSCell, as well as PUCCH SCells capable of sending PUCCH signals, may be disabled.

[0168] When a UE receives a PDCCH via SpCell indicating that it is exiting a dormant BWP outside of a set period (active time), it activates the downlink BWP indicated by the first downlink BWP identifier previously notified via RRC signaling.

[0169] When a UE receives a PDCCH via SpCell indicating that it will exit a dormant BWP within a set period (active time), it activates the downlink BWP indicated by a second downlink BWP identifier previously notified via RRC signaling.

[0170] Upon receiving a PDCCH indicating entry into a dormant BWP, the UE activates the downlink BWP indicated by the third downlink BWP identifier (dormantDownlinkBWP-Id) previously notified via RRC signaling.

[0171] The above-mentioned entry into and exit from dormant BWPs are performed by switching BWPs, and when a new BWP is activated, the BWP that was previously active is deactivated. In other words, when exiting a dormant BWP, the dormant BWP is deactivated, and when entering a dormant BWP, the dormant BWP is activated.

[0172] Here, we will explain PDCCH, which indicates entering a dormant BWP, and PDCCH, which indicates exiting a dormant BWP.

[0173] For example, a UE configured for intermittent reception (DRX) in a SpCell may monitor the PDCCH with the SpCell's Active BWP to detect a certain DCI format (e.g., DCI format 2_6) outside of the DRX active time. The CRC of the DCI format may be scrambled with a certain RNTI (e.g., PS-RNTI). A UE configured with dormant SCell groups may decide to switch the Active DL BWP based on the bitmap information contained in the DCI format 2_6 payload. For example, if a bit in the bitmap is associated with a dormant SCell group, and the bit is 1, the UE may switch to another pre-configured BWP if the Active DL BWP is a dormant BWP, or remain in that BWP if the Active DL BWP is not a dormant BWP. Alternatively, if the bit is 0, the UE may switch the BWP so that the Active DL BWP becomes a dormant BWP.

[0174] During the DRX's active time, the UE does not need to monitor the PDCCH for the purpose of detecting DCI format 2_6.

[0175] A UE configured for intermittent reception (DRX) in SpCell may monitor the PDCCH with the SpCell's Active BWP during the DRX active time to detect a certain DCI format (e.g., DCI formats 0_1 and 1_1). The CRC of the DCI format may be scrambled with a certain RNTI (e.g., C-RNTI or MCS-C-RNTI). A UE configured for dormant SCell groups may determine the switching of the Active DL BWP based on the bitmap information contained in the DCI format 0_1 ​​or DCI format 1_1 payload. For example, if a bit in the bitmap is associated with a dormant SCell group, and the bit is 1, the UE may switch to another pre-configured BWP if the Active DL BWP is a dormant BWP, or remain in that BWP if the Active DL BWP is not a dormant BWP. Alternatively, if the bit is 0, the UE may switch the BWP so that the Active DL BWP becomes a dormant BWP. Furthermore, the aforementioned "another pre-configured BWP" may be a different BWP from the "another pre-configured BWP" used in the explanation of DCI format 2_6.

[0176] The UE does not need to monitor the PDCCH for the purpose of detecting DCI format 0_1 ​​and DCI format 1_1 outside of the DRX's active time.

[0177] Monitoring the PDCCH to indicate exiting dormant BWP may involve monitoring the PDCCH outside of the DRX's active time for the purpose of detecting DCI format 2_6, and monitoring the PDCCH during the DRX's active time for the purpose of detecting DCI format 0_1 ​​and DCI format 1_1.

[0178] In each activated serving cell where a BWP is set, the MAC entity may perform some or all of the following (A) through (H) if the BWP is activated (is an Active BWP) and is not a dormant BWP. (A) Send UL-SCH with that BWP. (B) If a PRACH occasion is configured, send a RACH in that BWP. (C) Monitor the PDCCH with that BWP. (D) If PUCCH is configured, send PUCCH using that BWP. (E) Report the CSI using that BWP. (F) If SRS is configured, send SRS using that BWP. (G) Receive DL-SCH with that BWP. (H) Initialize the configured uplink grant of Grant Type 1 that was configured and suspended in that BWP.

[0179] In each activated serving cell where a BWP is set, the MAC entity may perform some or all of the following (A) through (G) if the BWP is activated (active BWP) and is dormant BWP. (A) If the BWP inactivity timer for this BWP serving cell is running, stop it. (B) Do not monitor the PDCCH of that BWP. (C) Do not monitor PDCCH for that BWP. (D) DL-SCH will not be received in that BWP. (F) Do not send SRS with that BWP. (G) Do not send UL-SCH with that BWP. (H) Do not send RACH with that BWP. (I) Do not send a PUCCH with that BWP. (J) Clear the configured downlink assignment and the configured uplink grant of grant type 2 associated with that SCell. (K) Suspend the configured uplink grant of Grant Type 1 associated with that SCell. (L) If beam failure settings are configured, detect beam failure, and if beam failure is detected, perform beam failure recovery.

[0180] If the BWP is deactivated, the MAC entity may perform some or all of the following (A) through (I): (A) Do not send UL-SCH with that BWP. (B) Do not send RACH with that BWP. (C) Do not monitor PDCCH with that BWP. (D) Do not send a PUCCH with that BWP. (E) Do not report CSI in that BWP. (F) Do not send SRS with that BWP. (G) Do not receive DL-SCH with that BWP. (H) Clear the Grant Type 2 Configured Ascending Link Grant set in that BWP. (I) Suspend the configured uplink grant of the inactive BWP (Inactive BWP) Grant Type 1.

[0181] Next, we will describe the random access procedure in a UE with a BWP configured. When a random access procedure is initiated in a serving cell, the MAC entity may perform some or all of the following operations (A) through (E) on the selected carrier of that serving cell. (A) If the resource (occasion) sending PRACH is not configured for the Active UL BWP, (A1) the Active UL BWP is switched to the BWP indicated by the RRC parameter (initialUplinkBWP), and (A2) if the serving cell is a SpCell, the Active UL BWP is switched to the BWP indicated by the RRC parameter initialDownlinkBWP. (B) If the resource (occasion) that sends PRACH is configured for the Active UL BWP, and the serving cell is a SpCell, and the Active DL BWP and Active UL BWP do not have the same identifier (bwp-Id), then the Active DL BWP is switched to a BWP with the same identifier as the Active UL BWP. (C) If the BWP inactivity timer associated with this serving cell's Active DL BWP is running, stop this timer. (D) If the serving cell is SCell, and if the BWP inactivity timer associated with the SpCell's Active DL BWP is running, stop this timer. (E) Execute a random access procedure on the Active DL BWP of SpCell and the Active UL BWP of this serving cell.

[0182] Next, we will explain the BWP inactivity timer. For each activated serving cell on which a BWP inactivity timer is set, the MAC entity performs the following (A) action. The BWP inactivity timer may also be named a timer called bwp-InactivityTimer. (A) If the default downlink BWP identifier (defaultDownlinkBWP-Id) is set and the Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), or if the default downlink BWP identifier (defaultDownlinkBWP-Id) is not set, the Active DL BWP is not initialDownlinkBWP, and the Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), then the MAC entity performs the following actions (A-1) and (A-2). (A-1) If an Active DL BWP receives a PDCCH addressed to C-RNTI or CS-RNTI indicating a downlink assignment or uplink grant, or if an Active DL BWP receives a PDCCH addressed to C-RNTI or CS-RNTI indicating a downlink assignment or uplink grant, or if a MAC PDU is sent in a configured uplink grant, or if a MAC PDU is received in a configured downlink assignment, the MAC entity performs the following (A-1-1): (A-1-1) If no random access procedure associated with this serving cell is currently running, or if a running random access procedure associated with this serving cell is successfully completed by receiving a PDCCH addressed to C-RNTI, start or restart the BWP inactivity timer associated with the Active DL BWP. (A-2) If the BWP inactivity timer associated with the Active DL BWP expires, the MAC entity performs the following action (A-2-1). (A-2-1) If defaultDownlinkBWP-Id is set, the BWP will be switched to the BWP indicated by defaultDownlinkBWP-Id; otherwise, the BWP will be switched to initialDownlinkBWP.

[0183] Furthermore, if the MAC entity receives a PDCCH for BWP switching and switches the Active DL BWP, it may perform the following (A) process. (A) If a default downlink BWP identifier (defaultDownlinkBWP-Id) is set, and the switched Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), and if the switched Active DL BWP is not the BWP indicated by dormantDownlinkBWP-Id, then start or restart the BWP inactivity timer associated with the Active DL BWP.

[0184] Next, we will describe the procedures for detecting and recovering beam failures.

[0185] In a MAC entity, a beam failure recovery procedure may be configured by the RRC for each serving cell. Beam failures are detected by counting beam failure instance notifications sent from lower layers (PHY layers) to the MAC entity. The MAC entity may perform some or all of the following processes (A), (B), and (C) in each serving cell for beam failure detection. (A) If a beam failure instance notification is received from a lower layer, start or restart the timer (beamFailureDetectionTimer) and increment the counter (BFI-COUNTER) by 1. If the value of BFI_COUNTER is greater than or equal to the set threshold (beamFailureInstanceMaxCount), perform the process in (A-1) below. (A-1) If the serving cell is an SCell, trigger beam failure recovery (BFR) for this serving cell; otherwise, initiate a random access procedure on the SpCell. (B) If the beamFailureDetectionTimer for this serving cell expires, or if the settings for beamFailureDetectionTimer, beamFailureInstanceMaxCount, and / or the reference signal for beam failure detection are changed by a higher layer, set BFI_COUNTER to 0. (C) If the serving cell is a SpCell and the random access procedure is successfully completed, set BFI_COUNTER to 0, stop the timer (beamFailureRecoveryTimer), and consider the beam failure recovery procedure to have been successfully completed. Otherwise, if the serving cell is an SCell and receives a PDCCH addressed to C-RNTI indicating a new uplink grant to transmit information for beam failure recovery of the SCell (e.g., information contained in the SCell BFR MAC CE), or if the SCell is inactive, set BFI_COUNTER to 0, consider the beam failure recovery procedure to have been successfully completed, and cancel all beam failure recoveries (BFRs) triggered for this serving cell.

[0186] If the MAC entity has triggered at least one beam failure recovery (BFR) by the beam failure recovery procedure and it has not been canceled, it performs the following action (A): (A) If the UL-SCH resource can include the SCell's BFR MAC CE and its subheaders, taking into account the logical channel priority, then include the SCell's BFR MAC CE and its subheaders. Otherwise, if the UL-SCH resource can include the SCell's truncated BFR MAC CE and its subheaders, taking into account the logical channel priority, then include the SCell's truncated BFR MAC CE and its subheaders. Otherwise, trigger a scheduling request for SCell beam failure recovery.

[0187] SCell dormancy is achieved by activating the dormant BWP within the SCell. Furthermore, even when an SCell is dormant, beam management, including CSI measurement, automatic gain control (AGC), and beam failure recovery, may be performed within the SCell.

[0188] Next, we will explain how to add SCG PSCells and zero or more SCells to a terminal device.

[0189] The addition of a PSCell and zero or more SCells to an SCG may be performed by an RRC message regarding the reconfiguration of the RRC connection. Figures 9 to 13 are examples of ASN.1 descriptions representing fields and / or information elements related to the addition of a PSCell and zero or more SCells to an SCG, as included in an RRC connection reconfiguration message in NR.

[0190] To avoid making the explanation too complicated, the messages and / or information elements in each diagram may differ from the actual message structure and / or information element structure, with some structured fields and information elements being expanded and / or fields and information elements not directly related to the explanation being omitted.

[0191] As shown in Figure 9, an RRCReconfiguration message may be used to add a PSCell and zero or more SCells to the SCG. The RRCReconfiguration message may include some or all of the information (A) through (E) below. In addition, the RRCReconfiguration message may include other information. (A) RRC transaction identifier (rrc-TransactionIdentifier) (B) Settings for adding, modifying, and releasing wireless bearers (radioBearerConfig) (C) Secondary Cell Group Settings (D) Master Cell Group Settings (masterCellGroup) (E) RRC settings for secondary cell groups in MR-DC (mrdc-SecondaryCellGroupConfig)

[0192] When an RRC reconfiguration message is sent to a terminal device via SRB3, the SCG setting may be notified by the setting in (C) above in the RRCReconfiguration message. Also, when an RRC reconfiguration message is sent to a terminal device via SRB1, the SCG setting may be notified by an RRC reconfiguration message generated by a secondary node, which is included in (E) above in the RRCReconfiguration message generated by the master node. In this case, the SCG setting may be notified by the setting in (C) above included in the RRC reconfiguration message generated by the secondary node. Alternatively, a different message may be used for SCG setting.

[0193] The settings for the secondary cell group described above may be provided by the CellGroupConfigIE element. As shown in Figure 10, the CellGroupConfigIE element may include some or all of the information (A) through (H) below. In addition, the CellGroupConfigIE element may include other information. (A) Cell group identifier (cellGroupId) (B) Settings for adding and / or modifying RLC bearers (rlc-BearerToAddModList) (C) RLC Bearer Release Settings (rlc-BearerToReleaseList) (D) MAC settings for this cell group (mac-CellGroupConfig) (E) PHY settings for this cell group (physicalCellGroupConfig) (F) SpCell settings (spCellConfig) (G) Settings for adding and modifying SCells (sCellToAddModList) (H) Settings for releasing SCells (sCellToReleaseList)

[0194] The SpCell settings in (F) above may add and / or configure SpCells, and the settings in (G) and (H) above may add, modify, and / or release SCells. These actions may also be performed by other messages.

[0195] The SpCell settings described above may include some or all of the information (A) through (D) below, as shown in Figure 11. The SpCell settings may also include other information. (A) An index (servCellIndex) for identifying serving cells from one another. (B) Reconfiguration with Sync (C) Information on timer values ​​and constants used for determining wireless link failures, etc. (rlf-TimersAndConstants) (D) Setting of terminal device-specific parameters for SpCell (spCellConfigDedicated)

[0196] The synchronized reset information elements described above may include some or all of the information (A) through (D) below, as shown in Figure 12. Furthermore, the synchronized reset information may also include other information. (A) Setting cell-specific parameters for SpCell (spCellConfigCommon) (B) The value of the new terminal identifier (UE-Identity) (newUE-Identity) (C) Timer T304 value (t304) (D) Setting terminal device-specific parameters for RACH (rach-ConfigDedicated)

[0197] The terminal device-specific parameters for RACH described above may include parameters used for continuation-free random access (CFRA). If CFRA is not included in the settings, the terminal device may perform contition-based random access in the random access procedure. CFRA may include information on RA occasions used in continuation-free random access.

[0198] The cell-specific parameters of the SpCell described above may be provided by an information element (ServingCellConfigCommon IE) used to set the cell-specific parameters of a serving cell. The information element used to set the cell-specific parameters of a serving cell may include some or all of the information (A) to (D) below, as shown in Figure 13. In addition, the information element used to set the cell-specific parameters of a serving cell may include other information. (A) Physical cell identifier (physCellId) (B) Common parameters for downlinks in cells (downlinkConfigCommon) (C) Common parameters for uplinks in cells (uplinkConfigCommon) (D) Setting of SCell terminal device-specific parameters (including some cell-specific parameters) (sCellConfigDedicated) (E) SSB subcarrier spacing information (ssbSubcarrierSpacing)

[0199] Common parameters for downlinks in a cell may include downlink frequency information (frequencyInfoDL) and / or initial downlink BWP information (initialDownlinkBWP). Downlink frequency information may include the SSB frequency information used in this serving cell.

[0200] The settings for adding or modifying the above SCell may be provided by one or more SCell configuration information elements (SCellConfigIE). As shown in Figure 14, the SCell configuration information elements may include some or all of the information (A) through (D) below. Furthermore, the SCell configuration information elements may also include other information. (A) Identifier that identifies a SCell (sCellIndex) (B) Setting cell-specific parameters for SCell (sCellConfigCommon) (C) Setting of SCell terminal device-specific parameters (including some cell-specific parameters) (sCellConfigDedicated) (D) Information indicating SCell activation / inactivation (sCellState-r16)

[0201] As an example, the procedure for adding a PSCell and zero or more SCells to an SCG using the above-mentioned RRC message and information elements is described below. Note that the RRC message and information elements used in this description are examples only, and the names and structures used in actual implementation are not limited to these examples.

[0202] The RRC entity of a terminal device that receives an RRCReconfiguration message may perform some or all of the following actions (A) through (F). The terminal device that receives an RRCReconfiguration message may perform other actions. (A) If RRCReconfiguration includes masterCellGroup, then process (BD-1) is performed on the master cell group based on this masterCellGroup. (B) If RRCReconfiguration includes a secondaryCellGroup, process (BD-1) is performed on the secondary cell group based on this secondaryCellGroup. (C) If RRCReconfiguration includes radioBearerConfig, configure the radio bearer based on this radioBearerConfig. (D) Set the content to be included in the RRC reset completion message. (E) If the SpCell configuration (spCellConfig) of the received secondary cell group configuration includes reconfigurationWithSync, start the random access procedure in that SpCell. (F) If the SpCell configuration (spCellConfig) of the MCG or SCG includes reconfigurationWithSync, and the above random access procedure is successfully completed in the NR cell group, the timer T304 for that cell group is stopped.

[0203] (Process BD-1) The RRC entity of the terminal device may perform some or all of the following (A) through (G): (A) If CellGroupConfig contains spCellConfig which includes reconfigurationWithSync, the RRC entity of the terminal device performs some or all of the following (1) to (3): (1) Execute process (BD-2). (2) Resume all suspended radio bearers. (3) Reactivate SCG transmission to all radio bearers if it has been suspended. (B) If CellGroupConfig contains rlc-BearerToReleaseList, the RLC bearer release will be performed based on this rlc-BearerToReleaseList. (C) If CellGroupConfig contains rlc-BearerToAddModList, add and / or modify RLC bearers based on this rlc-BearerToAddModList. (D) If CellGroupConfig contains mac-CellGroupConfig, set the MAC entity for this cell group based on this mac-CellGroupConfig. (E) If CellGroupConfig contains sCellToReleaseList, the SCell release will be performed based on this sCellToReleaseList. (F) If CellGroupConfig contains spCellConfig, configure SpCell based on this spCellConfig. (G) If CellGroupConfig contains sCellToAddModList, perform SCell additions and / or modifications based on this sCellToAddModList.

[0204] (Processing BD-2) The RRC entity of the terminal device may perform some or all of the actions in parentheses from (A) below. (A) If AS security is not activated, the procedure terminates after executing the process to transition to RRC_IDLE. (B) Start timer T304 for the SpCell (the one to be configured) using the value of t304 included in reconfigurationWithSync. (C) If the downlink frequency information (frequencyInfoDL) is included in reconfigurationWithSync, the cell indicated by the physical cell identifier (physCellId) included in reconfigurationWithSync at the SSB frequency indicated by frequencyInfoDL will be determined to be the target SpCell. (D) If the downlink frequency information (frequencyInfoDL) is not included in reconfigurationWithSync, the cell indicated by the physical cell identifier (physCellId) included in reconfigurationWithSync at the SSB frequency of the original SpCell (Source SpCell) is determined to be the target SpCell. (E) Start downlink synchronization of the target SpCell. (F) Obtain the MIB of the target SpCell (Acquire). (G) If no specific bearer (DAPS bearer) is configured, perform some or all of the following steps (1) through (4). (1) Reset the MAC entity of this cell group. (2) If this cell group contains a SCell that is not included in SCellToAddModList, set this SCell to an inactive state. (3) Apply the value of newUE-Identity as the C-RNTI for this cell group. (4) Configure the lower layer based on the received spCellConfigCommon.

[0205] Next, let's discuss Timer T304. Timer T304 may exist for each cell group. Additionally, the value of a timer (in this case, Timer T304) (information about the time at which the timer expires) may be notified via RRC messages. For example, if an RRC message indicates that the timer value is 1000ms, the timer may be considered to have expired if the notified time (1000ms in this example) has elapsed without the timer stopping after it has been started or restarted.

[0206] Based on receiving an RRC reconfiguration message including reconfigurationWithSync, the terminal device may start timer T304 for the cell group to which the reconfigurationWithSync setting is applied.

[0207] The terminal device may stop timer T304 of the cell group to which the reconfigurationWithSync setting is applied, based on the successful completion of random access to the target SpCell indicated by reconfigurationWithSync.

[0208] The terminal device may stop the timer T304 of the SCG based on the fact that the SCG has been released.

[0209] The terminal device may perform the RRC connection re-establishment procedure if the MCG timer T304 has expired and no specific bearer (DAPS bearer) has been configured.

[0210] The terminal device may notify the network of the failure of the synchronized reconfiguration by initiating the SCG failure information procedure once the SCG timer T304 has expired.

[0211] Further explanation will be given regarding the operation of the terminal device when the SCG timer T304 expires.

[0212] If the timer T304 of the secondary cell group expires, the RRC entity of the terminal device will perform the following process (A) if MCG transmission is not suspended, and the following process (B) if MCG transmission is suspended. (A) If a terminal device-specific preamble provided by trach-ConfigDedicated is set, release it and start the SCG failure information procedure to report the failure of the SCG synchronized reconfiguration. (B) Initiate the procedure to re-establish the RRC connection.

[0213] Next, we will explain the procedure for SCG failure information. This procedure may also be called the SCG failure information procedure.

[0214] This procedure may be used to notify the E-UTRAN or NR master node of an SCG failure experienced by a terminal device.

[0215] The RRC entity of the terminal device may initiate this procedure to report an SCG failure if MCG or SCG transmission is not suspended and any of the following conditions (A) through (D) are met: (A) Detected a wireless link failure in the SCG. (B) Detected a failure in the synchronized configuration of the SCG. (C)SCG configuration failure detected. (D) A failure in the integrity check for SRB3 was reported from a lower layer of SCG.

[0216] The RRC entity of the terminal device initiating this procedure performs some or all of the following (A) through (E): (A) Suspend SCG transmissions for all SRBs and DRBs. (B) Reset the SCG MAC. (C) If timer T304 in this SCG is running, stop it. (D) If a conditional reset for PSCell modification is set, stop this evaluation. (E) Configure the content to be included in the SCG Failure Information (SCGFailureInformation) message and submit it to the lower layer to send the message.

[0217] The lower layer of the RRC in the terminal device may transmit the above-mentioned SCG failure information (SCGFailureInformation) message to the base station device.

[0218] Next, we will explain the activation and deactivation of SCG.

[0219] In LTE and / or NR, the SCG deactivated state (SCG deactivated state) may be included as part of the RRC_CONNECTED state.

[0220] In LTE and / or NR, an inactive SCG state (SCG inactive state) is a state in which a terminal device performs some or all of the following (A) to (J) in its SCG SpCell (PSCell) and / or all cells of its SCG. (A) Do not send SRS in that cell. (B) Do not report a CSI for that cell. (C) Do not send PUCCH, UL-SCH, and / or RACH from that cell. (D) Do not monitor the PDCCH of that cell, and / or the PDCCH for that cell. (E) Do not monitor the PDCCH for that cell, and / or the PDCCH for that cell, addressed to C-RNTI, MCS-C-RNTI, and / or CS-RNTI, which indicate the uplink grant for UL-SCH transmission in that cell. (F) Automatic Gain Control (AGC) is not performed in that cell. (G) No beam control (beam management), including beam failure recovery, is performed in that cell. (H) Do not perform Radio Link Monitoring (RLM) in that cell. (I) In that cell, the BWP that was set to dormant BWP is set to activated BWP (Active BWP). (J) Do not monitor C-RNTI with PDCCH in the activated dormant BWP of that cell.

[0221] Furthermore, the state of becoming an inactive SCG may be referred to as "entering" an inactive SCG. The inactive SCG state may also be a state in which all cells of the SCG have dormant BWPs. Additionally, the aforementioned inactive SCG state may be a state transitioned from the activated SCG state (SCG active state), described later, when entry into an inactive SCG is instructed by an RRC entity.

[0222] In LTE and / or NR, the state in which the SCG is activated (SCG activated state) may be included as part of the RRC_CONNECTED state.

[0223] In LTE and / or NR, an activated SCG state (SCG activated state) is a state in which a terminal device performs some or all of the following (A) to (J) in its SCG's SpCell (PSCell) and / or any cell of its SCG. (A) Send an SRS in that cell. (B) Report the CSI for that cell. (C) Send PUCCH, UL-SCH, and / or RACH from that cell. (D) Monitor the PDCCH of that cell and / or the PDCCH for that cell. (E) Monitor the PDCCH of that cell and / or the PDCCH for that cell, addressed to the C-RNTI, MCS-C-RNTI, and / or CS-RNTI for UL-SCH transmission in that cell. (F) Perform Automatic Gain Control (AGC) in that cell. (G) Perform beam control (beam management) including beam failure recovery in that cell. (H) Perform Radio Link Monitoring (RLM) in that cell. (I) Do not activate the BWP set to the dormant BWP as the Active BWP in that cell. (J) Monitor the C-RNTI with the PDCCH in the Active BWP of that cell.

[0224] Also, the state of the SCG becoming active may be referred to as Entering the activated SCG. Also, the SCG active state may be a state where the Active BWP of the SpCell and / or one or more SCells of the SCG is not the dormant BWP. Also, the above-mentioned SCG inactive state may be a state that transitions from the state where the SCG is deactivated (SCG inactive state) when leaving the SCG deactivated from the RRC entity is instructed.

[0225] In LTE and / or NR, the terminal device may transition the SCG to the inactive state (in other words, deactivate the SCG) based on receiving some or all of the following (A) to (B). Note that the messages and control elements from (A) to (B) below may be notified to the terminal device from a cell group other than the said SCG. Also, each piece of information may be notified to the terminal device in an RRC message, a MAC information element, or a physical control channel. (A) Information indicating the deactivation of the SCG (B) Information indicating the deactivation of the SpCell <00,00910> Furthermore, the terminal device may transition the SCG from an active state to an inactive state based on a timer for SCG deactivation. Alternatively, the terminal device may transition the SCG from an active state to an inactive state based on a timer for PSCell deactivation.

[0227] Furthermore, the terminal device may transition the SCG from an inactive state to an active state when initiating a random access procedure resulting from a scheduling request (in other words, initiated by the MAC entity itself). The MAC entity of the terminal device may also obtain instructions to activate the SCG, instructions to return from an inactive SCG, instructions to return from a dormant state of SpCell, and / or other information from the RRC entity of the terminal device.

[0228] In LTE and / or NR, a terminal device may transition the SCG from an inactive state to an active state (in other words, activate the SCG) based on receiving some or all of (A) through (D) below. Note that the messages and control elements in (A) through (D) below may also be notified to the terminal device from cell groups other than the SCG in question. Furthermore, each piece of information may be notified to the terminal device via RRC messages, MAC information elements, or physical control channels. (A) Information that instructs the activation of SCG (B) Information instructing the SCG to resume from its deactivated state. (C) Information instructing the activation of SpCell (D) Information instructing SpCell to recover from the inactive state.

[0229] Furthermore, the terminal device may transition the SCG from an inactive state to an active state based on a timer for SCG deactivation. Alternatively, the terminal device may transition the SCG from an inactive state to an active state based on a timer for PSCell deactivation.

[0230] Furthermore, the terminal device may transition the SCG from an inactive state to an active state when initiating a random access procedure resulting from a scheduling request triggered to transmit a MAC PDU containing a MAC SDU.

[0231] Furthermore, the terminal device may transition the SCG from an inactive state to an active state when initiating a random access procedure resulting from a scheduling request (in other words, initiated by the MAC entity itself). The MAC entity of the terminal device may also obtain instructions to activate the SCG, instructions to return from an inactive SCG, instructions to return from a dormant state of SpCell, and / or other information from the RRC entity of the terminal device.

[0232] SCG inactivation may also be referred to as entering a dormant SCG. Alternatively, SCG inactivation may refer to the activation of a dormant BWP in the SpCell of the cell group in question. Furthermore, SCG inactivation may also be referred to as SCG dormancy or SCG suspension.

[0233] When an SCG is inactive, all uplink transmissions in the SCG may be stopped. In this case, information about the SCG may be transmitted in other cell groups (e.g., MCGs). Alternatively, information about the SCG may be transmitted in the SCG that has left the inactive state (an activated SCG).

[0234] A random access procedure in a SpCell (PSCell) may be initiated in an inactive SCG, either by a scheduling request from a MAC entity to send a MAC PDU containing a MAC CE, or directly by a MAC entity. In this case, the MAC PDU may not contain a MAC SDU.

[0235] On the other hand, a scheduling request to send a MAC PDU containing data from higher layers, such as user data and RRC messages (MAC SDU), may trigger the random access procedure in the SpCell (PSCell) in an inactive SCG.

[0236] The recovery of an SCG from an inactive state (activation of SCG) may also be referred to as leaving a dormant SCG. Furthermore, the recovery of an SCG from an inactive state may also refer to a BWP switch in the SpCell of the cell group in question, where a dormant BWP is replaced by another (non-dormant) BWP.

[0237] Furthermore, the recovery of SCG from an inactivated state may be referred to as SCG activation.

[0238] A terminal device that performs SCG deactivation may perform some or all of the following processes (A) to (F) in the SCG. (A) Set all SCells to an inactive state. (B) Assume that all SCell deactivation timers associated with active SCells have expired. (C) All SCell inactivity timers associated with dormant SCells are considered to have expired. (D) Do not start or restart the SCell inactive timer associated with any SCell. (E)Ignore the MAC CE for activating the SCell. For example, in the above processing (AD), when receiving the MAC CE for activating the SCell and not being instructed to deactivate the SCG (or the SCG is not in the deactivated state), perform the processing (AD-1). (F)Execute the above processing (AD-2). For example, in the above processing (AD), when being instructed to deactivate the SCG (or the SCG has entered the deactivated state), perform the processing (AD-2).

[0239] A terminal device that executes the return from the deactivated state of the SCG may perform some or all of the following processes (A) to (D) in the SCG. (A)Execute the processing (AD-1) to set all SCell to the active state. (B)Keep all SCell in the inactive state. However, since it is not in the deactivated state, for example, in the above processing (AD), when receiving the MAC CE for activating the SCell and not being instructed to deactivate the SCG (or the SCG is not in the deactivated state), the processing (AD-1) may be performed. (C)When executing the return from the deactivated state of the SCG based on the RRC message, if the RRC message contains parameters related to random access for some or all of the SCell, start the random access procedure for the target SCell based on the notified parameters. (D)When executing the return from the deactivated state of the SCG based on the RRC message, if the RRC message contains information specifying the state of the SCell, determine whether to set the state of each SCell to the active state or the inactive state based on that information.

[0240] Based on the above description, various embodiments of the present invention will be described. Note that the above-described processes may be applied to each process omitted in the following description.

[0241] Figure 5 is a block diagram showing the configuration of a terminal device (UE122) in an embodiment of the present invention. Note that, to avoid complicating the explanation, Figure 5 shows only the main components closely related to one embodiment of the present invention.

[0242] The UE122 shown in Figure 5 consists of a receiving unit 500 that receives RRC messages etc. from the base station equipment, a processing unit 502 that processes according to the parameters contained in the received message, and a transmitting unit 504 that transmits RRC messages etc. to the base station equipment. The base station equipment mentioned above may be an eNB102 or a gNB108. Furthermore, the processing unit 502 may include some or all of the functions of various layers (for example, the physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and NAS layer). That is, the processing unit 502 may include some or all of the physical layer processing unit, MAC layer processing unit, RLC layer processing unit, PDCP layer processing unit, SDAP layer processing unit, RRC layer processing unit, and NAS layer processing unit.

[0243] Figure 6 is a block diagram showing the configuration of a base station device in an embodiment of the present invention. To avoid a complicated explanation, Figure 6 shows only the main components closely related to one embodiment of the present invention. The base station device described above may be either an eNB102 or a gNB108.

[0244] The base station device shown in Figure 6 consists of a transmitting unit 600 that sends RRC messages, etc., to the UE 122, a processing unit 602 that creates an RRC message including parameters and sends it to the UE 122, causing the processing unit 502 of the UE 122 to perform processing, and a receiving unit 604 that receives RRC messages, etc., from the UE 122. Furthermore, the processing unit 602 may include some or all of the functions of various layers (for example, the physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and NAS layer). That is, the processing unit 602 may include some or all of the physical layer processing unit, MAC layer processing unit, RLC layer processing unit, PDCP layer processing unit, SDAP layer processing unit, RRC layer processing unit, and NAS layer processing unit.

[0245] The following describes various examples of processing by the terminal device in embodiments of the present invention.

[0246] Figure 15 shows an example of processing by a terminal device in an embodiment of the present invention.

[0247] The terminal device (UE122) receives an RRC message from the base station device (eNB102 or gNB108) (step S1500). This RRC message may contain information to determine whether to activate or deactivate the secondary cell group.

[0248] The terminal device may initiate a random access procedure in the SpCell of a secondary cell group based on whether the received RRC message contains information indicating that the secondary cell group should be activated or not. The terminal device may refrain from initiating a random access procedure in the SpCell of a secondary cell group based on whether the received RRC message contains information indicating that the secondary cell group should be deactivated or not (step S1502).

[0249] Furthermore, the terminal device may start the first timer based on whether the received RRC message contains information indicating that the secondary cell group should be activated or not. The terminal device may not start the first timer based on whether the received RRC message contains information indicating that the secondary cell group should be deactivated or not. The terminal device may stop the first timer based on whether the random access procedure in the SpCell of the secondary cell group has been successfully completed. The terminal device may also stop the first timer when the secondary cell group is released and / or deactivated. When the first timer has expired, the terminal device may start an SCG failure information procedure to report SCG failure information. The SCG failure information may include information indicating that SCG activation failed.

[0250] A terminal device may deactivate a cell group based on whether the received RRC message contains information indicating that the cell group should be deactivated or not. A terminal device may activate a cell group based on whether the received RRC message contains information indicating that the cell group should be activated or not, and whether the random access procedure in the cell group's SpCell has been successfully completed.

[0251] This allows the terminal device to efficiently activate and deactivate cell groups.

[0252] The following is an example where the above RRC message is an RRC reset message. The terminal device receives the RRC reset message from the base station device (eNB102 or gNB108). This RRC reset message may include information to determine whether to activate or deactivate the secondary cell group.

[0253] If the RRC reset message contains a synchronized reset information element for the secondary cell group settings, the terminal device will (1) initiate a random access procedure based on whether the received RRC reset message contains information indicating that the secondary cell group should be activated or not, or (2) not initiate a random access procedure based on whether the received RRC reset message contains information indicating that the secondary cell group should be deactivated or not, or not, information indicating that the secondary cell group should be activated.

[0254] Furthermore, the terminal device will not start Timer T304 based on the fact that the received RRC reset message contains information indicating that the secondary cell group should be deactivated, even if the secondary cell group setting in the RRC reset message includes a synchronized reset information element. Alternatively, the terminal device will start Timer T304 based on the fact that the secondary cell group setting in the RRC reset message includes a synchronized reset information element, and will stop Timer T304 based on the fact that the received RRC reset message contains information indicating that the secondary cell group should be deactivated, or does not contain information indicating that the secondary cell group should be activated.

[0255] This allows terminal devices to efficiently activate and deactivate cell groups using RRC reset messages.

[0256] This document describes a method for indicating whether to activate or deactivate an SCG when adding an SCG PSCell and zero or more SCells to a terminal device.

[0257] The terminal device receives an RRC message that adds a PSCell to the SCG and zero or more SCells. This RRC message may be the RRC reset message shown in Figure 9. When a PSCell is added, the RRC message may include a synchronized reset information element that includes the setting of cell-specific parameters of the SpCell, such as the physical cell identifier.

[0258] Furthermore, the RRC message may include information indicating whether the SCG is in an active or inactive state. For example, this information may be included in the settings of the target cell group (e.g., the cell group setting information element). Alternatively, for example, this information may be included in the synchronized reset information element contained within the cell group setting information element of the target cell group. Alternatively, this information may be included in any information element included in the RRC message.

[0259] The aforementioned information may indicate whether a cell group should be in an active or inactive state. Alternatively, the aforementioned information may indicate that a cell group should be in an active state. In this case, the cell group may be inactive based on the absence of this information. Alternatively, the aforementioned information may indicate that a cell group should be in an inactive state. In this case, the cell group may be in an active state based on the absence of this information. Furthermore, the aforementioned information may be indicated by other information elements. Note that if the aforementioned information is not included in the settings for the target cell group, the aforementioned information may include information indicating which cell group is the target. Also, if there is only one cell group that could be the target (secondary cell group), the aforementioned information does not need to include information indicating which cell group is the target.

[0260] For example, the information may be a field (scgState-r17) whose value is of type ENUMERATED and is "deactivated". In this case, the terminal device may determine that the field (scgState-r17) whose value is "deactivated" is a cell group that will deactivate the target cell group when included in the RRC message, and that the field whose value is not included in the RRC message is a cell group that will activate the target cell group. Alternatively, for example, the information may be a field (scgState-r17) whose values ​​are of type ENUMERATED and are "deactivated" and "activated". In this case, the terminal device may determine that the field (scgState-r17) whose value is "deactivated" is a cell group that will deactivate the target cell group when included in the RRC message, and that the field (scgState-r17) whose value is "activated" is a cell group that will activate the target cell group when included in the RRC message, and that the RRC message is not a message to activate and / or deactivate the cell group when this field is not included in the RRC message.

[0261] Upon receiving an RRC reset message, the RRC entity of the terminal device may perform some or all of the following actions (A) through (D). (A) If RRCReconfiguration includes a secondaryCellGroup, perform (A-1) through (A-7) below on the secondary cell group based on this secondaryCellGroup. (A-1) If CellGroupConfig contains spCellConfig which includes reconfigurationWithSync, the RRC entity of the terminal device will perform some or all of the following (A-1-1) through (A-1-9). (A-1-1) If AS security is not activated, the procedure terminates after executing the process to transition to RRC_IDLE. (A-1-2) Start timer T304 for the SpCell (to be configured) using the value of t304 included in reconfigurationWithSync. However, if the RRC reconfiguration message contains information indicating that the cell group to be configured should be deactivated, timer T304 may not be started. If the RRC reconfiguration message contains information indicating that the cell group to be configured should be deactivated, timer T304 may be stopped if it is running. (A-1-3) If the downlink frequency information (frequencyInfoDL) is included in reconfigurationWithSync, the cell indicated by the physical cell identifier (physCellId) included in reconfigurationWithSync at the SSB frequency indicated by frequencyInfoDL will be determined to be the target SpCell. (A-1-4) If the downlink frequency information (frequencyInfoDL) is not included in reconfigurationWithSync, the cell indicated by the physical cell identifier (physCellId) included in reconfigurationWithSync at the SSB frequency of the original SpCell (Source SpCell) is determined to be the target SpCell. (A-1-5) Start downlink synchronization of the target SpCell. (A-1-6) Obtain the MIB of the target SpCell (Acquire). (A-1-7) If no specific bearer (DAPS bearer) is configured, perform some or all of the following steps (A-1-7-1) through (A-1-7-4). (A-1-7-1) Reset the MAC entity for this cell group. (A-1-7-2) If this cell group contains a SCell that is not included in SCellToAddModList, deactivate that SCell. (A-1-7-3) Apply the value of newUE-Identity as C-RNTI for this cell group. (A-1-7-4) Configure the lower layer based on the received spCellConfigCommon. (A-1-8) Resume all suspended wireless bearers. However, if the RRC reset message contains information indicating that the cell group to be configured should be deactivated, some suspended wireless bearers (e.g., SRB3) may not be resumed (or all suspended wireless bearers except for some wireless bearers (e.g., SRB3) may be resumed). Some wireless bearers (e.g., SRB3) may be suspended if the RRC reset message contains information indicating that the cell group to be configured should be deactivated. (A-1-9) If SCG transmission to all wireless bearers has been suspended, resume it. Here, if the RRC reset message contains information indicating that the cell group to be set to reset should be deactivated, SCG transmission to all wireless bearers may be suspended. (A-2) If CellGroupConfig contains rlc-BearerToReleaseList, the RLC bearer release will be performed based on this rlc-BearerToReleaseList. (A-3) If CellGroupConfig contains rlc-BearerToAddModList, add and / or modify RLC bearers based on this rlc-BearerToAddModList. (A-4) If CellGroupConfig contains mac-CellGroupConfig, the MAC entity for this cell group will be set based on this mac-CellGroupConfig. (A-5) If CellGroupConfig contains sCellToReleaseList, the SCell will be released based on this sCellToReleaseList. (A-6) If CellGroupConfig contains spCellConfig, configure SpCell based on this spCellConfig. (A-7) If CellGroupConfig contains sCellToAddModList, then SCell additions and / or modifications will be performed based on this sCellToAddModList. (B) Set the content to be included in the RRC reset completion message. (C) If the SpCell configuration (spCellConfig) of the received secondary cell group configuration includes reconfigurationWithSync, the random access procedure is initiated in that SpCell. However, if the RRC reconfiguration message contains information indicating that the cell group to be configured should be deactivated, the random access procedure may not be initiated in the SpCell of the target cell group. Alternatively, if the RRC reconfiguration message contains information indicating that the cell group to be configured should be deactivated, the MAC entity of the target cell group may be notified that the cell group will be deactivated. (D) If the SpCell configuration (spCellConfig) of the MCG or SCG includes reconfigurationWithSync, and the above random access procedure is successfully completed in the NR cell group, the timer T304 of that cell group is stopped. Here, if the RRC reconfiguration message includes information indicating that the cell group to be configured should be deactivated, the timer T304 of that cell group may be stopped if the SpCell configuration (spCellConfig) of the MCG or SCG includes reconfigurationWithSync. Alternatively, if the RRC reconfiguration message includes information indicating that the cell group to be configured should be deactivated, the MAC entity of the cell group to be configured may be notified that the cell group will become active.

[0262] Furthermore, the terminal device may stop the T304 of its SCG based on the fact that the SCG has been released and / or that the SCG has become inactive.

[0263] A terminal device may deactivate a secondary cell group based on whether the received RRC configuration message contains information indicating that the secondary cell group should be deactivated, or whether it does not contain information indicating that the secondary cell group should be activated. A terminal device may activate a secondary cell group based on whether the received RRC configuration message contains information indicating that the secondary cell group should be activated, or whether it does not contain information indicating that the secondary cell group should be deactivated, and whether the random access procedure in the SpCell of that secondary cell group has been successfully completed.

[0264] This allows terminal devices to efficiently activate and deactivate cell groups using RRC reset messages.

[0265] Furthermore, the above procedure can also be applied to indicating whether to activate or deactivate the SCG configured on the terminal device, without adding any PSCells and / or SCells to the SCG.

[0266] Another method for indicating to a terminal device whether to activate or deactivate the SCG is described below.

[0267] The terminal device receives an RRC message. This RRC message may be the RRC reset message shown in Figure 9, or it may be any other RRC message.

[0268] The RRC message may include information indicating whether to activate or deactivate the SCG.

[0269] The aforementioned information may indicate whether to activate or deactivate a cell group. Alternatively, the aforementioned information may indicate that the cell group should be activated. In this case, the cell group may be deactivated based on the absence of this information. Alternatively, the aforementioned information may indicate that the cell group should be deactivated. In this case, the cell group may be activated based on the absence of this information. The aforementioned information may also be indicated by other information elements. If the aforementioned information is not included in the settings for the target cell group, the aforementioned information may include information indicating which cell group is the target. If there is only one cell group that could be the target (secondary cell group), the aforementioned information does not need to include information indicating which cell group is the target. Furthermore, the information indicating that the cell group should be activated may include an information element (rach-ConfigDedicated) containing terminal device-specific parameters used in the random access procedure.

[0270] In a terminal device that receives an RRC message that contains information indicating to activate a cell group or does not contain information indicating to deactivate a cell group, the RRC entity of the terminal device may perform some or all of the following (A) to (F). (A) Start a second timer (also referred to here as timer T304X) for the SpCell of the target cell group. The value used for the second timer may be included in the RRC message, the value of t304 may be used, or a default value may be used. (B) Resume all suspended radio bearers. (C) Reactivate SCG transmission to all radio bearers if it was suspended. (D) Initiate a random access procedure in the SpCell of the target cell group. (E) Once the random access procedure described above is successfully completed in the target cell group, the second timer for that cell group is stopped. (F) Notify the MAC entity of the target cell group that the cell group has become active.

[0271] Furthermore, in a terminal device that receives an RRC message that contains information indicating that a cell group should be deactivated, or does not contain information indicating that a cell group should be activated, the RRC entity of the terminal device may perform some or all of the following (A) to (D). (A) If a second timer (also referred to here as Timer T304X) for the SpCell of the target cell group is running, stop it. (B) Suspend some wireless bearers (e.g., SRB3). (C) Suspend SCG transmissions to all radio bearers. (D) Notify the MAC entity of the target cell group that the cell group has become inactive.

[0272] The terminal device may stop the second timer of its SCG based on the fact that the SCG has been released and / or that the SCG has become inactive.

[0273] The operation of the terminal device when the second timer expires will now be described.

[0274] If the RRC entity of the terminal device has completed the second timer of the secondary cell group, it will perform the following process (A) if MCG transmission is not suspended, and the following process (B) if MCG transmission is suspended. (A) If a terminal device-specific preamble provided by trach-ConfigDedicated is set, release it and start the SCG failure information procedure to report the failure of the SCG synchronized reconfiguration. (B) Initiate the procedure to re-establish the RRC connection.

[0275] This allows terminal devices to efficiently activate and deactivate cell groups using RRC messages.

[0276] This section describes the mechanism of conditional reconfiguration in NR. The network may configure one or more target SpCell candidates on a terminal device through conditional reconfiguration. The terminal device may evaluate the conditions for each configured target SpCell candidate. The terminal device may select one cell from each target SpCell candidate that satisfies the execution conditions associated with each candidate and apply the conditional reconfiguration associated with that cell. The network may provide the configuration for the target SpCell to the terminal device using a ConditionalReconfiguration IE. The terminal device may store the conditional reconfiguration information provided by the ConditionalReconfiguration IE as one or more entries in a variable (VarConditionalReconfig).

[0277] When a terminal device receives an RRC reconfiguration message, if the SCG's SpCell setting (spCellConfig) includes reconfigurationWithSync, the variable (VarConditionalReconfig) may be retained if the RRC reconfiguration message is intended to activate an SCG that is inactive on the terminal device, or to deactivate an SCG that is active on the terminal device. If the RRC reconfiguration message is not intended to activate an SCG that is inactive on the terminal device, nor is it intended to deactivate an SCG that is active on the terminal device, all entries in the variable (VarConditionalReconfig) may be deleted.

[0278] An example of an embodiment will be described. A terminal device communicating with a base station device receives a first RRC message from the base station device instructing the addition of a SpCell to the first cell group, and a second RRC message instructing the first cell group to transition from a first state in which the SpCell does not monitor the PDCCH to a second state in which the SpCell monitors the PDCCH. The terminal device may include a processing unit that starts a first timer when it receives the first RRC message (Upon reception) and starts a second timer when it receives the second RRC message. The processing unit of the terminal device may further generate failure information for the first cell group based on the expiration of the first timer or the second timer.

[0279] For example, the first cell group may be a secondary cell group. The first RRC message may be an RRC reset message that includes a synchronized reset information element. The second RRC message may be an RRC reset message or another RRC message. The first timer may be timer T304. The first state may be a state in which the SCG is deactivated. The second state may be a state in which the SCG is activated. The generation of failure information for the first cell group may be initiated by starting the SCG failure information procedure.

[0280] Furthermore, the processing unit may stop the first timer based on the fulfillment of any of the following conditions: that random access to the SpCell is successfully completed, that the first cell group is released, or that the first cell group has entered a first state. Furthermore, the processing unit may stop the second timer based on the fulfillment of any of the following conditions: that random access to the SpCell is successfully completed, that the first cell group is released, or that the first cell group has entered a first state.

[0281] An example of an embodiment will be described. The terminal device may include a receiving unit that receives a first RRC message from a base station device that includes parameters for synchronous reconfiguration of the SpCell of a first cell group, and a processing unit that starts a first timer based on the reception of the first RRC message. The processing unit may determine whether or not to start the first timer based on whether or not the first RRC message contains first information, and may generate failure information for the first cell group based on the expiration of the first timer.

[0282] The first cell group may be a secondary cell. The synchronous reset may be a synchronous reset information element included in the RRC reset message, or a part of the information included in the synchronous reset information element. That is, the first RRC message may be an RRC reset message. The first information may be information indicating that the first cell group is to be deactivated. Alternatively, it may indicate that the first cell group is to be activated if the first information is not included. The first timer may be timer T304. The generation of the first cell group failure information may be the initiation of the SCG failure information procedure.

[0283] An example of an embodiment will be described. The terminal device may include a receiving unit that receives a first RRC message from a base station device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group, a processing unit that processes the first RRC message, and a transmitting unit that transmits a random access preamble in the SpCell based on the reception of the first RRC message. The processing unit may determine whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0284] The first cell group may be a secondary cell. The synchronous reset may be a synchronous reset information element included in the RRC reset message, or a part of the information included in the synchronous reset information element. That is, the first RRC message may be an RRC reset message. The first information may be information indicating that the first cell group is to be deactivated. Alternatively, it may indicate that the first cell group is to be activated if the first information is not included.

[0285] An example of an embodiment will be described. The terminal device may include a receiving unit that receives a first RRC message from the base station device that includes parameters for synchronous reconfiguration of the SpCell of a first cell group, and a processing unit that resumes suspended radio bearers based on the reception of the first RRC message. The processing unit may determine whether or not to resume all suspended radio bearers based on whether or not the first RRC message contains first information. The processing unit may also determine whether or not to resume SCG transmission to all suspended radio bearers based on whether or not the first RRC message contains first information.

[0286] The first cell group may be a secondary cell. The synchronous reset may be a synchronous reset information element included in the RRC reset message, or a part of the information included in the synchronous reset information element. That is, the first RRC message may be an RRC reset message. The first information may be information indicating that the first cell group is to be deactivated. Alternatively, it may indicate that the first cell group is to be activated if the first information is not included.

[0287] In the above explanation, an example was shown in which the base station device uses an RRC reset message (first message) containing a synchronized reset information element, or another RRC message (second message), to instruct the terminal device to activate and deactivate a cell group that has been set on the terminal device. However, the explanation is not limited to this, and the first message may be used to activate a cell group and the second message to deactivate it, or the second message may be used to activate a cell group and the first message to deactivate it.

[0288] Furthermore, the RRC entity of the terminal device that deactivates the SCG may perform some or all of the following (A) through (E): (A) Suspend SCG transmissions for all SRBs and DRBs. (B) Reset the SCG MAC. (C) If the first timer in this SCG is running, stop it. (D) If a conditional reset for PSCell modification is set, stop this evaluation. (E) Submit to the lower layer to send a message indicating that deactivation is complete.

[0289] Furthermore, the RRC entity of the terminal device that activates the SCG may perform some or all of the following (A) to (D). (A) Resume SCG transmissions for all SRBs and DRBs. (B) Reset the SCG MAC. (C)If a conditional reset for PSCell changes is configured, start (or restart) this evaluation. (D) Submit to the lower layer to send a message indicating that activation is complete.

[0290] Furthermore, "includes information indicating that the cell group should be deactivated" does not necessarily mean that the terminal device does not directly include information indicating that the cell group should be deactivated. For example, "includes information indicating that the cell group should be deactivated" may simply mean that the first piece of information is included, or that the second piece of information is not included. The terminal device may perform the above processing based on whether the first piece of information is included or whether the second piece of information is not included. Similarly, "includes information indicating that the cell group should be activated" does not necessarily mean that the terminal device does not directly include information indicating that the cell group should be activated. For example, "includes information indicating that the cell group should be activated" may simply mean that the second piece of information is included, or that the first piece of information is not included. The terminal device may perform the above processing based on whether the second piece of information is included or whether the first piece of information is not included.

[0291] The above-mentioned ReconfigurationWithSync information element is always included in the configuration of a secondary cell group when (A) adding a PSCell, (B) resuming SCG transmission from a suspended state in an NR-DC or (NG)EN-DC, (C) updating system information required by the PSCell, and (D) changing the security key of the AS. Furthermore, it may also be made to always be included when activating and / or deactivating the SCG.

[0292] "Includes information indicating that the cell group will be deactivated" may include "does not include information indicating that the cell group will be activated." Similarly, "Includes information indicating that the cell group will be activated" may include "does not include information indicating that the cell group will be deactivated."

[0293] Furthermore, the activation (inactivation) of a cell group and the activation (inactivation) of the SpCells within that cell group may be interchangeable. Similarly, putting a cell group into an activated (inactive) state and putting the SpCells within that cell group into an activated (inactive) state may be interchangeable.

[0294] In the above description, the wireless bearer may be a DRB, an SRB, or both a DRB and an SRB.

[0295] Furthermore, in the above explanation, expressions such as "link," "correspond," and "associate" may be used interchangeably.

[0296] Furthermore, in the above explanation, "the aforementioned..." may be replaced with "the aforementioned...".

[0297] Furthermore, in the above explanation, "SCG's SpCell" may be replaced with "PSCell".

[0298] In the above explanation, "dormant state" may be replaced with "inactive state," and "state after recovering from dormancy" may be replaced with "active state." Also, in the above explanation, "activation" and "inactivation" may be replaced with "active state" and "inactive state," respectively.

[0299] In the above explanation, "transition from X to Y" can be rephrased as "become X to Y." Also, "activated BWP" can be rephrased as "Active BWP."

[0300] Furthermore, in the examples of processes or process flows described above, some or all of the steps may not be executed. Also, in the examples of processes or process flows described above, the order of the steps may differ. Also, in the examples of processes or process flows described above, some or all of the processes within each step may not be executed. Also, in the examples of processes or process flows described above, the order of the processes within each step may differ. Furthermore, in the above description, "perform B based on A being true" may be rephrased as "perform B." That is, "performing B" may be performed independently of "being A being true."

[0301] Furthermore, in the above explanation, "A may be replaced with B" may include not only replacing A with B, but also replacing B with A. Also, in the above explanation, if it states "C may be D" and "C may be E", it may also include "D may be E". Also, in the above explanation, if it states "F may be G" and "G may be H", it may also include "F may be H".

[0302] Furthermore, in the above explanation, if condition "A" and condition "B" are contradictory, condition "B" may be expressed as an "other" condition of condition "A".

[0303] The following describes various embodiments of the terminal device and method according to the present invention.

[0304] (1) A first embodiment of the present invention is a terminal device that communicates with a base station device, comprising: a receiving unit that receives a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group; a processing unit that processes the first RRC message; and a transmitting unit that transmits a random access preamble in the SpCell based on the reception of the first RRC message, wherein the processing unit determines whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0305] (2) A second embodiment of the present invention is a base station device that communicates with a terminal device, comprising: a transmitting unit that transmits to the terminal device a first RRC message containing parameters for synchronous reconfiguration of a SpCell of a first cell group; and a receiving unit that receives a random access preamble transmitted from the terminal device by the SpCell based on the first RRC message, wherein the terminal device is instructed to determine whether or not to transmit the random access preamble in the SpCell based on whether or not to include first information in the first RRC message.

[0306] (3) A third embodiment of the present invention is a method applied to a terminal device that communicates with a base station device, comprising the steps of: receiving a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group; processing the first RRC message; and transmitting a random access preamble in the SpCell based on the receipt of the first RRC message, wherein it is determined whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0307] (4) A fourth embodiment of the present invention is a method applied to a base station device that communicates with a terminal device, comprising the steps of: sending a first RRC message to the terminal device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group; and receiving a random access preamble transmitted from the terminal device by the SpCell based on the first RRC message, wherein the terminal device determines whether or not to transmit the random access preamble in the SpCell based on whether or not to include first information in the first RRC message.

[0308] (5) A fifth embodiment of the present invention is an integrated circuit implemented in a terminal device that communicates with a base station device, which causes the terminal device to perform the following functions: receiving a first RRC message from the base station device that includes parameters for synchronous reconfiguration of a first cell group's SpCell; processing the first RRC message; and transmitting a random access preamble in the SpCell based on the reception of the first RRC message, and determining whether or not to transmit the random access preamble in the SpCell based on whether or not the first RRC message contains first information.

[0309] (6) A sixth embodiment of the present invention is an integrated circuit implemented in a base station device that communicates with a terminal device, which causes the base station device to perform the functions of transmitting a first RRC message to the terminal device that includes parameters for synchronous reconfiguration of a SpCell of a first cell group, and receiving a random access preamble transmitted from the terminal device by the SpCell based on the first RRC message, and causes the terminal device to determine whether or not to transmit the random access preamble in the SpCell depending on whether or not the first information is included in the first RRC message.

[0310] A program that operates in a device according to one aspect of the present invention may be a program that controls a Central Processing Unit (CPU), etc., to make the computer function in order to realize the functions of the above-described embodiment according to one aspect of the present invention. The program or information handled by the program is temporarily loaded into volatile memory such as Random Access Memory (RAM) during processing, or stored in non-volatile memory such as flash memory or a Hard Disk Drive (HDD), and read, modified, and written by the CPU as needed.

[0311] Furthermore, a part of the apparatus in the above-described embodiment may be implemented using a computer. In that case, the program for implementing this control function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be loaded into a computer system and executed. The term "computer system" here refers to a computer system built into the apparatus, and includes hardware such as an operating system and peripheral devices. The "computer-readable recording medium" may be any of the following: a semiconductor recording medium, an optical recording medium, a magnetic recording medium, etc.

[0312] Furthermore, "computer-readable recording media" may include those that dynamically hold programs for a short period of time, such as communication lines used when transmitting programs via networks such as the Internet or communication lines such as telephone lines, as well as those that hold programs for a certain period of time, such as volatile memory within the computer system acting as a server or client in such cases. In addition, the above-mentioned program may be for the purpose of realizing some of the functions described above, and may also be a program that can realize the above-mentioned functions in combination with a program already recorded in the computer system.

[0313] Furthermore, each functional block or feature of the apparatus used in the embodiments described above may be implemented or executed by an electrical circuit, typically an integrated circuit or a combination of integrated circuits. Electrical circuits designed to perform the functions described herein may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gates or transistor logic, discrete hardware components, or combinations thereof. The general-purpose processor may be a microprocessor, or alternatively, the processor may be a conventional processor, controller, microcontroller, or state machine. The general-purpose processor, or each of the aforementioned circuits, may consist of digital circuits or analog circuits. Also, if advances in semiconductor technology lead to the emergence of integrated circuit technologies that replace current integrated circuits, it may be possible to use integrated circuits based on such technologies.

[0314] It should be noted that the present invention is not limited to the embodiments described above. Although the embodiments describe an example of a device, the present invention is not limited thereto and can be applied to stationary or non-movable electronic devices installed indoors or outdoors, such as terminal devices or communication devices for AV equipment, kitchen equipment, cleaning and washing machines, air conditioning equipment, office equipment, vending machines, and other household appliances.

[0315] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and design modifications and the like that do not depart from the gist of this invention are also included. Furthermore, various modifications are possible within the scope of the claims for one aspect of the present invention, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. In addition, configurations in which elements described in the above embodiments that produce similar effects are substituted for each other are also included. [Industrial applicability]

[0316] One aspect of the present invention can be used, for example, in communication systems, communication equipment (e.g., mobile phone devices, base station devices, wireless LAN devices, or sensor devices), integrated circuits (e.g., communication chips), or programs. [Explanation of symbols]

[0317] 100 E-UTRA 102 eNB 104 EPC 106 NR 108 gNB 110 5GC 112, 114, 116, 118, 120, 124 Interfaces 122 UE 200, 300 PHY 202, 302 MAC 204, 304 RLC 206, 306 PDCP 208, 308 RRC 310 SDAP 210, 312 NAS 500, 604 Receiver 502, 602 processing unit 504, 600 Transmitter

Claims

1. A terminal device that communicates with a base station device, A receiving unit that receives a first RRC message from the base station device containing parameters for synchronous reconfiguration of the SpCell of the first cell group, A processing unit that processes the first RRC message, The system includes a transmission unit that transmits a random access preamble using the SpCell based on the reception of a first RRC message, The aforementioned processing unit, If the spCellConfig, which is the setting for the first cell group, includes reconfigurationWithSync, the random access procedure in the SpCell is initiated. If the first RRC message contains information indicating that the first cell group should be deactivated, the random access procedure in the SpCell is not initiated. Terminal device.

2. A base station device that communicates with terminal devices, A transmission unit that transmits a first RRC message to the terminal device, which includes parameters for synchronous reconfiguration of the SpCell of the first cell group. The system includes a receiving unit that receives a random access preamble transmitted from a terminal device via the SpCell based on a first RRC message, By including reconfigurationWithSync in spCellConfig, which is the setting for the first cell group, the terminal device is instructed to start the random access procedure in the SpCell. A base station device that prevents the terminal device from initiating the random access procedure in the SpCell by including information in the first RRC message indicating that the first cell group should be deactivated.

3. A method applicable to a base station device that communicates with a terminal device, The steps include sending a first RRC message to the terminal device containing parameters for synchronous reconfiguration of the SpCell of the first cell group, The process includes the step of receiving a random access preamble transmitted from a terminal device to the SpCell based on a first RRC message, If the spCellConfig, which is the setting for the first cell group, includes reconfigurationWithSync, the random access procedure in the SpCell is initiated. If the first RRC message contains information indicating that the first cell group should be deactivated, the random access procedure in the SpCell is not initiated. method.

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