Network node and communication method

Abstract

A network node is provided with: a communication unit that receives, from a terminal via an RAN node, a registration request including information indicating the use of two master nodes, the RAN node being a wireless access network; and a control unit that holds two terminal contexts for each of the master nodes, the control unit holding a master node identifier, remaining terminal radio capabilities, and remaining terminal radio resources corresponding to the RAN node in the terminal contexts for each of the master nodes, and the control unit controlling the terminal contexts for each of the master nodes on the basis of the terminal contexts for each of the master nodes. And a communication unit that derives two CM states of the terminal, the CM being connection management, and that notifies the other of the two master nodes of the remaining terminal radio capabilities and remaining terminal radio resources included in the terminal context of each of the master nodes corresponding to one of the two master nodes.

Description

Technical Field

[0001] The present invention relates to a network node and a communication method in a communication system. Background Art

[0002] The 3rd Generation Partnership Project (3GPP) is researching wireless communication methods called 5G or NR (New Radio) (hereinafter referred to as "5G" or "NR") to achieve further increases in system capacity, higher data transmission speeds, and lower latency within wireless networks. In 5G, various wireless technologies are being studied to meet the requirements of achieving a throughput of 10 Gbps or more and keeping latency within wireless networks to 1 ms or less.

[0003] In NR, research is underway on a network architecture that includes 5GC (5G Core Network) corresponding to EPC (Evolved Packet Core), which is the core network in the network architecture of LTE (Long Term Evolution), and NG-RAN (Next Generation-Radio Access Network) corresponding to E-UTRAN (Evolved Universal Terrestrial Radio Access Network), which is the RAN (Radio Access Network) in the network architecture of LTE (for example, non-patent document 1).

[0004] Prior art literature

[0005] Non-patent literature

[0006] Non-Patent Document 1: 3GPP TS 23.501 V18.0.0 (2022-12)

[0007] Non-Patent Document 2: 3GPP TS 38.413 V17.3.0 (2022-12)

[0008] Non-Patent Document 3: 3GPP TS 33.501 V18.0.0 (2022-12)

[0009] Non-Patent Document 4: 3GPP TS 38.304 V17.2.0 (December 2022)

[0010] Non-Patent Document 5: 3GPP TS 23.502 V18.0.0 (December 2022)

[0011] Non-Patent Document 6: 3GPP TS 24.501 V18.1.0 (December 2022)

[0012] Non-Patent Document 7: 3GPP TS 29.244 V18.0.1 (December 2022)

[0013] Non-Patent Document 8: 3GPP TS 24.193 V18.0.0 (December 2022)

[0014] Non-Patent Document 9: 3GPP TS 38.331 V17.3.0 (2022-12)

[0015] Non-Patent Document 10: 3GPP TS 38.300 V17.3.0 (December 2022) Summary of the Invention

[0016] Problems to be solved by the invention

[0017] During the 5G transition, DC (Dual Connectivity) was adopted to stabilize coverage during the initial phase of wireless system introduction. However, DC is difficult to implement in a multi-vendor environment. Therefore, in the transition to next-generation wireless systems, it is desirable to achieve stable coverage during the initial phase of introduction without using DC.

[0018] Here, in the DC, the MN (Master Node) predominantly implements the allocation of terminal wireless capabilities between the MN and the SN via the Xn interface, as well as the allocation of wireless resources when frequency sharing exists between the MN and the SN. In methods that do not use a DC, in which two base stations operate on the network side, processing related to the allocation of wireless resources is also required.

[0019] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to execute allocation of radio resources in a radio communication system in which both base stations operate as master nodes.

[0020] Means for solving problems

[0021] According to the disclosed technology, a network node is provided, which includes: a communication unit, which receives a registration request including information indicating the use of two master nodes from a terminal via a RAN node, wherein the RAN is a radio access network; and a control unit, which maintains two terminal contexts for each master node, wherein the control unit maintains a master node identifier, remaining terminal wireless capabilities, and remaining terminal wireless resources corresponding to the RAN node in the terminal context of each master node, wherein the control unit derives two CM states of the terminal based on the terminal context of each master node, wherein the CM is connection management, and wherein the communication unit notifies the other of the two master nodes of the remaining terminal wireless capabilities and remaining terminal wireless resources corresponding to one of the two master nodes and included in the terminal context of each master node.

[0022] Effects of the Invention

[0023] According to the disclosed technology, in a wireless communication system in which both base stations operate as master nodes, wireless resources can be allocated. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a diagram for explaining an example of a communication system.

[0025] Figure 2 This is a diagram for explaining an example of a communication system in a roaming environment.

[0026] Figure 3 This is a diagram for explaining an example of a network in the embodiment of the present invention.

[0027] Figure 4 This is a sequence diagram for explaining an example of initial setting and setting change in the embodiment of the present invention.

[0028] Figure 5 This is a sequence diagram for explaining an example of cell selection in an embodiment of the present invention.

[0029] Figure 6 This is a sequence diagram for explaining an example of a registration procedure in the embodiment of the present invention.

[0030] Figure 7 This is a sequence diagram for explaining example (1) of the PDU session establishment procedure according to an embodiment of the present invention.

[0031] Figure 8 This is a sequence diagram for explaining example (2) of the PDU session establishment procedure according to an embodiment of the present invention.

[0032] Figure 9 This is a sequence diagram of Example (3) of the PDU session establishment procedure for explaining an embodiment of the present invention.

[0033] Figure 10 1 is a diagram showing an example of the functional configuration of the base station 10 and the network node 30 according to the embodiment of the present invention.

[0034] Figure 11 This is a diagram showing an example of the functional configuration of the terminal 20 in the embodiment of the present invention.

[0035] Figure 12 This is a diagram showing an example of the hardware configuration of the base station 10 and the terminal 20 in the embodiment of the present invention.

[0036] Figure 13 This is a diagram showing an example of the structure of a vehicle 2001 in the embodiment of the present invention. DETAILED DESCRIPTION

[0037] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0038] When operating the wireless communication system according to the embodiments of the present invention, existing technologies are appropriately used. However, such existing technologies are, for example, existing LTE, but are not limited to existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning, including LTE-Advanced, and post-LTE-Advanced technologies (e.g., NR), or wireless LANs (Local Area Networks), unless otherwise specified.

[0039] Furthermore, in the embodiment of the present invention, “configuring” wireless parameters and the like may be pre-configuring predetermined values, or may be configuring wireless parameters notified from the network node 30 or the terminal 20 .

[0040] Figure 1 is a diagram for explaining an example of a communication system. Figure 1 As shown, the communication system is composed of a UE (terminal terminal) 20 and multiple network nodes 30. Hereinafter, each function is assumed to correspond to one network node 30, but multiple functions may be implemented by one network node 30, or one function may be implemented by multiple network nodes 30. Furthermore, the "connection" described below may refer to either a logical connection or a physical connection.

[0041] RAN (Radio Access Network) is a network node 30 with a radio access function, which may include a base station 10 and is connected to the UE, AMF (Access and Mobility Management Function) and UPF (User plane function). AMF is a network node 30 with functions such as termination of the RAN interface, termination of NAS (Non-Access Stratum), registration management, connection management, reachability management, and mobility management. UPF is a network node 30 with functions such as an external PDU (Protocol Data Unit) session point interconnected with DN (Data Network), routing and forwarding of packets, and QoS (Quality of Service) processing of the user plane. UPF and DN constitute a network slice. In the wireless communication network in the embodiment of the present invention, multiple network slices are constructed.

[0042] The AMF is connected to the UE, RAN, SMF (Session Management Function), NSSF (Network Slice Selection Function), NEF (Network Exposure Function), NRF (Network Repository Function), UDM (Unified Data Management), AUSF (Authentication Server Function), PCF (Policy Control Function), and AF (Application Function). The AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are interconnected via the interfaces Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf based on their respective services.

[0043] SMF is a network node 30 that has functions such as session management, UE IP (Internet Protocol) address allocation and management, DHCP (Dynamic Host Configuration Protocol) function, ARP (Address Resolution Protocol) proxy, roaming function, etc. NEF is a network node 30 that has the function of notifying other NFs (Network Function) of capabilities and events. NSSF is a network node 30 that has functions such as selecting the network slice to which the UE is connected, determining the allowed NSSAI (Network Slice Selection Assistance Information), determining the set NSSAI, and determining the AMF set to which the UE is connected. PCF is a network node 30 that has the function of performing network policy control. AF is a network node 30 that has the function of controlling application servers. NRF is a network node 30 that has the function of discovering NF instances that provide services. UDM is a network node 30 that manages subscriber data and authentication data. UDM is connected to the UDR (User Data Repository) that stores this data.

[0044] Figure 2 FIG is a diagram for explaining an example of a communication system in a roaming environment. Figure 2 As shown, the network is composed of a UE (terminal terminal) 20 and multiple network nodes 30. Hereinafter, it is assumed that there is one network node 30 corresponding to each function. However, one network node 30 may implement multiple functions, or multiple network nodes 30 may implement one function. Furthermore, the "connection" described below may refer to either a logical connection or a physical connection.

[0045] The RAN is a network node 30 with radio access functionality, connected to the UE, AMF, and UPF. The AMF is a network node 30 that performs functions such as RAN interface termination, NAS termination, registration management, connection management, reachability management, and mobility management. The UPF is a network node 30 that connects to the DN, serves as an external PDU session point, performs packet routing and forwarding, and handles user plane QoS. The UPF and DN constitute a network slice. Multiple network slices are constructed in the wireless communication network in this embodiment of the present invention.

[0046] The AMF is connected to the UE, RAN, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, AF, and SE PP (Security Edge Protection Proxy). The AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are interconnected via the service-based interfaces Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf.

[0047] SMF is a network node 30 that has functions such as session management, UE IP address allocation and management, DHCP function, ARP proxy, and roaming function. NEF is a network node 30 that has the function of notifying other NFs of capabilities and events. NSSF is a network node 30 that has functions such as selecting the network slice to which the UE is connected, determining the allowed NSSAI, determining the set NSSAI, and determining the AMF set to which the UE is connected. PCF is a network node 30 that has the function of performing policy control of the network. AF is a network node 30 that has the function of controlling the application server. NRF is a network node 30 that has the function of discovering NF instances that provide services. SEPP is a non-transparent proxy that filters messages on the control plane between PLMNs (Public Land Mobile Network). Figure 2 The vSEPP shown is a SEPP in a visited network, and the hSEPP is a SEPP in a home network.

[0048] like Figure 2 As shown, the UE is in a roaming environment, connected to the RAN and AMF in a VPLMN (Visited Public Land Mobile Network). The VPLMN and HPLMN (Home Public Land Mobile Network) are connected via vSEPP and hSEPP. The UE can communicate with the UDM of the HPLMN via the AMF of the VPLMN, for example.

[0049] In this context, during the transition to 5G, DC (Dual Connectivity) was used to stabilize coverage during the initial phase of wireless system introduction. However, DC is difficult to implement in a multi-vendor environment. Therefore, in the transition to next-generation wireless systems, it is desirable to achieve stable coverage during the initial phase of introduction without using DC.

[0050] In addition, dual registration is also standardized as a 5G transfer method. The purpose of introducing dual registration is to solve the interaction between EPC and E-UTRA and 5GC and NR in the absence of N26 (refer to non-patent document 1) as the interface between AMF and MME. In the case of 5GC and E-UTRA, there is no sufficient solution for dual registration regarding the situation of registering to both EPC and 5GC via the same E-UTRA cell. Therefore, in the case where the next-generation core network is an extension of 5GC, the dual registration standardized in the 5G transfer method cannot be used.

[0051] That is, when the next-generation core network is envisioned as an extension of 5GC, it is expected that a method without using DC can be used to stabilize the coverage in the initial stage of the introduction of the next-generation wireless system, but such a method does not currently exist.

[0052] Therefore, when the terminal registers or connects to the network, the terminal may have two MNs (Master Nodes). Figure 3 This is a diagram for explaining an example of a network in an embodiment of the present invention. The terminal newly introduces a structure having two RRC (Radio Resource Control: Radio Resource Control) states, two CM (Connection management: Connection management) states, and one registration state (RM (Registration management: Registration management) state). QoS flows can be distributed or divided between two MNs. In addition, the cells used in waiting and paging can also be limited. Figure 3 As shown, two MNs can identify each other via AMF and select an appropriate mobile destination MN during handover.

[0053] In addition, existing standards related to registration define the RM-DEREGISTERED and RM-REGISTERED states. Both the terminal and the AMF have RM states. RM state transitions are based on NAS signals. For a terminal, independent RM states are defined for each access. Access can include, for example, 3GPP access and non-3GPP access.

[0054] In addition, existing connection-related standards define the CM-IDLE and CM-CONNECTED states. The terminal and the AMF each have a CM state. CM state transitions are based on RRC signals for the terminal and N2 signals for the AMF, which are used as an interface with the RAN. For a terminal, independent CM states are defined for each access. Access includes, for example, 3GPP access and non-3GPP access.

[0055] In addition, in the existing standards, ATSSS (Access Traffic Steering, Switching, Splitting) handles the distribution and splitting of QoS flows between 3GPP access and non-3GPP access.

[0056] For example, AMF can manage one RM state and two CM states for the 3GPP access of the terminal. AMF can also keep the MN identifier, Global RAN Node ID (refer to non-patent document 1), RAN UE NGAP (NG Application Protocol) ID (refer to non-patent document 2), and AMF UE NGAP ID (refer to non-patent document 2) in each newly imported MN level terminal context, which has two in total, instead of in each access level terminal context. AMF can use the MN level terminal context for message routing between RAN and SMF, K gNB (See Non-Patent Document 3) Differentiation, derivation of CM states for each connection, and derivation of UE-CM states indicating terminal reachability. For 3GPP access, a terminal can manage one RM state and two CM states. Furthermore, the RAN UE NGAP ID is an identifier used within the RAN node to identify a UE on the NG interface, and the AMF UE NGAPID is an identifier used within the AMF to identify a UE on the NG interface.

[0057] For example, the SMF can allocate the QoS flows of a PDU session among multiple MNs. The SMF can notify the RAN of policies and allocate the QoS flows of a PDU session among multiple MNs based on the RAN's decision. The SMF can request the terminal to send a PDU session change request from another MN to an existing PDU session accessed by 3GPP. The RAN can determine the QoS flow distribution and QoS flow segmentation of the PDU session based on the policies notified by the SMF. The terminal can send a PDU session change request from a second MN to an existing PDU session accessed by 3GPP based on the instructions notified by the SMF.

[0058] For example, the RAN may configure paging activation or paging deactivation. Paging deactivation indicates that a RAN node does not perform paging. In the case of paging deactivation, the RAN may notify the terminal of this information using broadcast information and the AMF using a terminal-independent N2 message. The AMF may also not send N2 paging to a RAN with paging deactivation. The terminal may not consider cells of a RAN with paging deactivation as candidates for cell selection or cell reselection. While camping on a RAN cell with paging activated as usual, the terminal may also consider cells of a RAN with paging deactivation as candidates for cell selection or cell reselection.

[0059] For example, based on settings, the RAN may prioritize selecting another RAN as the handover destination if there is a nearby RAN with a different RAT (Radio Access Technology) than the "buddy RAN node" serving as the other MN in a dual MN configuration. Alternatively, if there is another nearby RAN with the same RAT as the buddy RAN node, that RAN may be prioritized as the handover destination. The RAN may select the handover destination based on information about the buddy RAN node notified by the AMF. The AMF may notify the RAN of information about the buddy node. The AMF may also notify the RAN of information about the buddy node when transitioning to CM-Connection for both MNs.

[0060] Figure 4 This is a sequence diagram illustrating an example of initial setup and configuration changes in an embodiment of the present invention. In step S101a, the RAN node 10A sends an NG SETUP REQUEST to the AMF 30A (see Non-Patent Document 2). In the following step S102a, the AMF 30A sends an NG SETUP Response to the RAN node 10A. Here, the RAN node 10A is an example of a RAN node that is activated by paging.

[0061] Meanwhile, in step S101b, the RAN node 10B sends an NG SETUP request to the AMF 30A, including a paging disable indication with a dummy value set in the Supported Tracking Area list (Supported Tracking Area list) (see Non-Patent Document 2). In the following step S102a, the AMF 30A sends an NG SETUP response to the RAN node 10B. Here, the RAN node 10B is an example of a RAN node for which paging is disabled, and when the RAN is a next-generation system, the paging disable indication can be set. Thereafter, the AMF 30A does not use the RAN node 10B for paging.

[0062] In step S103a, the RAN node 10A sends a RAN configuration update (RAN CONFIGURATION UPDATE) to the AMF 30A. In the next step S104a, the AMF 30A sends a RAN configuration update confirmation (RAN CONFIGURATION UPDATE ACKNOWLEDGE) to the RAN node 10A.

[0063] On the other hand, in step S103b, the RAN node 10B sends a RAN setting update including a paging disable indication to the AMF 30A. In the following step S104b, the AMF 30A sends a RAN setting update confirmation to the RAN node 10B. Thereafter, the AMF 30A does not use the RAN node 10B for paging.

[0064] Figure 5 This is a sequence diagram illustrating an example of cell selection in an embodiment of the present invention. In step S201, the RAN node 10B transmits broadcast information to the UE 20, including the information element cellNotForPaging:true indicating that paging is disabled (see Non-Patent Document 5). In the following step S202, the UE 20 does not select the cell of the RAN node 10B as a candidate for cell selection or cell reselection unless it is camped on another normal cell.

[0065] Here, in the DC, the MN takes the lead in allocating terminal wireless capabilities (e.g., frequency band combinations, functional groups) between the MN and the SN via the Xn interface, as well as allocating wireless resources when frequency sharing occurs between the MN and the SN. In a dual-MN architecture that does not use a DC, both base stations operate on the network side, requiring processing related to wireless capability and wireless resource allocation.

[0066] Therefore, the RAN node notifies the AMF of the terminal radio capabilities (i.e., remaining terminal radio capabilities) and radio resources (i.e., remaining terminal radio resources) available to the partner RAN node. The AMF maintains the remaining terminal radio capabilities and remaining terminal radio resources while the CM-connection is established with the RAN node. When establishing a CM-connection with the partner RAN node, the AMF notifies the partner RAN node of the remaining terminal radio capabilities and remaining terminal radio resources. The partner RAN node can, for example, consider all terminal radio capabilities, the remaining terminal radio capabilities, and the remaining terminal radio resources when setting a QoS flow.

[0067] In addition, regarding all terminal wireless capabilities, RAN and AMF can operate in accordance with existing standards as shown below.

[0068] 1) If the RAN does not receive the capability from the AMF, it obtains the capability from the terminal and notifies the AMF of the capability.

[0069] 2)AMF maintains this capability while the terminal is RM-registered.

[0070] 3)AMF notifies the RAN of the capability.

[0071] Figure 6This is a sequence diagram for illustrating an example of a registration step in an embodiment of the present invention. In steps S301 and S302, UE20 sends a registration request message including a new dual MN indication IE (Information Element) to AMF30A via NR and NG-RAN or via next-generation radio and next-generation RAN. In addition, the RAN node corresponding to the RAT and RAN used in step S301 will be referred to as RAN node 10A below. UE20 sets the newly defined UE-CM state to UE-CM-Connected. The UE-CM state means that when there is at least one CM-connection, it is set to UE-CM-Connected, and when there is no CM-connection, it is set to UE-CM-Idle.

[0072] In the following step S303, AMF 30A stores the MN identifier corresponding to RAN node 10A, the Global RAN Node ID corresponding to RAN node 10A, the RAN UE NGAP ID corresponding to UE 20, and the AMF UE NGAP ID corresponding to UE 20 within each MN-level terminal context. AMF 30A stores the MN identifier set to MN#1, the Global RAN Node ID of RAN node 10A obtained in advance during the NG SETUP step, the RAN UE NGAP ID obtained from RAN node 10A, and the AMF UE NGAP ID that has been allocated by AMF 30A or will be allocated later. AMF 30A sets the newly defined UE-CM state to UE-CM-Connected.

[0073] In addition, each MN-level terminal context may also include a ULI (User Location Information) indicating user location information. Furthermore, in existing standards, the AMF 30A maintains a set of RAN UE NGAP ID, AMF UE NGAP ID, and ULI in each access-level terminal context (see Non-Patent Document 5).

[0074] In the next step S304, the AMF 30A sends an Initial Context Setup request (see Non-Patent Document 2) to the RAN node 10A (see Non-Patent Document 5). This message does not include the terminal's wireless capabilities.

[0075] In the next step S305, the RAN node 10A sends a UE Capability Enquiry message (see Non-Patent Document 9) to the UE 20. In the next step S306, the UE 20 sends a UE Capability Information to the RAN node 10A. The UE Capability Information may include all or part of the terminal's wireless capabilities.

[0076] In the following step S307, RAN node 10A sends a UE Radio Capability Info Indication (see Non-Patent Document 2) to AMF 30A. The UE Radio Capability Info Indication may include all of the terminal's radio capabilities. In the following step S308, AMF 30A stores all or part of the terminal's radio capabilities in the terminal context for the entire terminal corresponding to UE 20.

[0077] In step S309, the AMF 30A, UE 20, and RAN node 10A perform the usual registration procedure. In step S310, the AMF 30A sends a Registration Permit to UE 20. In step S311a, the AMF 30A sets the RM state to RM Registered. In step S312a, after completing the registration procedure, the AMF 30A sets the CM state to CM-Idle. In other words, the AMF 30A sets the UE-CM state to UE-CM-Idle.

[0078] In step S311b, the UE 20 that has received the registration permission sets the RM state to RM registered. In step S312b, the UE 20 sets the CM state to CM-idle after the registration step is completed. That is, the UE 20 sets the UE-CM state to UE-CM idle.

[0079] Furthermore, when the UE 20 transmits a registration request next time, it can appropriately use the available RAT and RAN regardless of the RAN node 10A used this time.

[0080] Figure 7This is a timing diagram of example (1) of the PDU session establishment step for illustrating an embodiment of the present invention. In steps S401 and S402, UE20 sends a PDU session establishment request to AMF30A via NR and NG-RAN or via next generation wireless and next generation RAN (see non-patent document 5). The PDU session establishment request includes a 5GSM (5GS Session Management) capability IE (see non-patent document 6). In the ATSSS-ST bit of the 5GSM capability IE, information indicating "QoS flow splitting performed by RAN" is newly set. The UL NAS transmission that carries the PDU session establishment request sets the request category to "MAPDU request" and sets the request subcategory to "3GPP access multiple connections" (see non-patent document 5). In addition, the RAN node corresponding to the RAT and RAN used in step S401 will be referred to as the RAN node 10A below.

[0081] In the next step S403, AMF30A maintains the MN identifier set to MN#1, the Global RAN No de ID of the RAN node 10A obtained in advance in the NG SETUP step, the RAN UE NGAP ID obtained from the RAN node 10A, and the AMF UE NGAP ID that AMF30A has allocated or will allocate later in each MN level terminal context.

[0082] In the next step S404, AMF 30A selects SMF 30B (see Non-Patent Document 5). In the next step S405, AMF 30A sends Nsmf_PDUSession_CreateSMContextRequest (see Non-Patent Document 5) including the PDU session establishment request to SMF 30B. Nsmf_PDUSession_CreateSMContextRequest includes the MN identifier set to MN#1.

[0083] In the following step S406, SMF 30B considers the possibility of adding another MN. It first assumes that MN#1 has configured all QoS flows and sends a PFCP (Packet Forwarding Control Protocol) session establishment request to UPF 30C (see Non-Patent Document 7). This PFCP session establishment request includes a Create MAR IE. This Create MAR IE includes a 3GPP Access MN#1Forwarding IE. Furthermore, in the case of existing ATSSS, the Create MAR IE includes a 3GPP Access Forwarding Action Information IE and a Non-3GPP AccessForwarding Action Information IE (see Non-Patent Document 7). In the following step S407, UPF 30C sends a PFCP session establishment response to SMF 30B.

[0084] In the next step S408, SMF 30B sends a Namf_Communication_N1N2MessageTransfer message containing a PDU Session Resource Setup Request Transfer IE to AMF 30A (see Non-Patent Document 5). This PDU Session Resource Setup Request Transfer IE includes a multi-MN permission indication and information indicating QoS flow splitting performed by the RAN. This Namf_Communication_N1N2MessageTransfer message includes the MN identifier set to MN#1. SMF 30B also sends a PDU Session Establishment Permit (see Non-Patent Document 6) to UE 20 within this Namf_Communication_N1N2MessageTransfer message. This PDU Session Establishment Permit includes a PDU Session Branch Setup Request indication via another MN.

[0085] In the following step S409, the AMF 30A compares the MN identifier received from the SMF 30B, set to MN#1, with the locally maintained terminal contexts for each MN level. As a result of this comparison, the AMF 30A recognizes that MN#1 corresponds to the RAN node 10A. In the following step S410, the AMF 30A transfers the PDUSession Resource Setup Request Transfer IE within the received Namf_Communication_N1N2MessageTransfer message via an N2PDU session request. The message sent to the RAN 10A is a PDU session establishment request (see Non-Patent Document 2), which includes the message received in step S409 and all or part of the terminal's wireless capabilities.

[0086] In the following step S411, the RAN node 10A detects the presence of another RAN node #B near the UE 20 based on a measurement report received from the UE 20. In the following step S412, the RAN node 10A determines appropriate QoS flow distribution or QoS flow splitting between its own device and RAN node #B, referring to all or part of the terminal's radio capabilities and information from OAM (Operations Administration and Maintenance). QoS flow distribution involves allocating each QoS flow to the own device or another RAN. QoS flow splitting involves splitting a single QoS flow, with the own device carrying a portion and another RAN carrying the remainder. In the case of QoS flow splitting, the RAN node 10A can set the splitting ratio based on instructions from the UE 20 and / or UPF 30C. The determination made by the RAN node 10A in step S412 can be similar to that in the DC case, except that the splitting ratio for QoS flow splitting is based on instructions from the UE 20 and / or UPF 30C.

[0087] Figure 8 This is a sequence diagram illustrating Example (2) of the PDU session establishment procedure according to an embodiment of the present invention. In step S413, RAN node 10A establishes a QoS flow with UE 20 that is determined to be carried entirely or partially by its own device (see Non-Patent Document 5). RAN node 10A also transmits a PDU Session Establishment Permit to UE 20.

[0088] In the following step S414, RAN node 10A sends a message including a PDU Session Resource Setup Response Transfer IE (see Non-Patent Document 5) to AMF 30A. The QoS Flow Failed to Setup List IE included in this PDU Session Resource Setup Response Transfer IE specifies the unestablished QoS flows, and the QoS flows to be targeted for QoS flow partitioning are specified in a new IE, the QoS Flow Partly Setup List IE. In addition to the IE, the PDU Session Resource Setup Response Transfer IE may also specify a traffic ratio for RAN node 10A. The message sent to AMF 30A is a PDU Session Resource Setup Response, which includes the remaining terminal radio capabilities (i.e., the terminal radio capabilities available to RAN node 10B) and the remaining terminal radio resources (i.e., the terminal radio resources available to RAN node B).

[0089] In the next step S415, the AMF 30A stores the remaining terminal radio capabilities and the remaining terminal radio resources in each MN-level terminal context corresponding to the MN identifier set as MN#1.

[0090] In the next step S416, AMF 30A sends an Nsmf_PDUSession_UpdateSMContext Request (see Non-Patent Document 5) including the received PDU Session Resource Setup Response Transfer IE to SMF 30B. This Nsmf_PDUSession_UpdateSMContext Request message includes the MN identifier set to MN#1.

[0091] In the following step S417, SMF 30B sends a PFCP session change request to UPF 30C to set the QoS flow for MN#1, the ratio of the QoS flow for MN#1 based on the QoS Flow Partly Setup List IE indicating the QoS flow for MN#1 for the divided QoS flow, and the TEID (Tunnel Endpoint Identifier) ​​on the MN#1 side. The ratio of the QoS flow for MN#1 is set in the Update 3GPP Access MN#1 Forwarding Action Information IE included in the PFCP session change request. In the following step S418, UPF 30C sends a PFCP session change response to SMF 30B.

[0092] After establishing the QoS flow in step S413, UE 20 sends a PDU session change request to RAN node 10B in step S419. UE 20 sets the same PDU session ID in this PDU session change request as in the PDU session establishment request in step S401. In the following step S420, RAN node 10B confirms the 5G-S-TMSI (Temporary Mobile Subscriber Identity) within the RRC message containing the received PDU session change request and forwards the PDU session change request to the same AMF 30A (see Non-Patent Document 5).

[0093] In the next step S421, AMF30A maintains the MN identifier set to MN#2 in each MN-level terminal context, the Global RAN No de ID of the RAN node 10B obtained in advance in the NG SETUP step, the RAN UE NGAP ID obtained from the RAN node 10B, and the AMF UE NGAP ID that AMF30A has allocated or will allocate later.

[0094] In the next step S422, AMF 30A sends a UE context change request to RAN node 10A. The UE context change request message includes a newly defined partner RAN node IE. The partner RAN node IE can be the Global RAN Node ID or RAT category of RAN node 10B.

[0095] In the following step S423, because the PDU session ID of the received PDU session change request is the same as that of the already established PDU session, AMF 30A selects the same SMF 30B. In the following step S424, AMF 30A sends an Nsmf_PDUSession_UpdateS MContext Request message to SMF 30B (see Non-Patent Document 5) containing the received PDU session change request. This Nsmf_PDUSession_UpdateS MContext Request message includes the MN identifier set to MN#2.

[0096] In the next step S425, upon receiving the Nsmf_PDUSession_UpdateSMContextRequest message, SMF 30B confirms the QoS Flow Failed to Setup List IE and QoS Flow Partly Setup List IE received in step S416, and determines the QoS flow that needs to be set in MN#2.

[0097] In the next step S426, since the PDU session ID of the PDU session change request included in the Nsmf_PDUSession_UpdateSMContext Request message is the same as the established PDU session, the SMF 30B selects the same UPF 30C.

[0098] In the following step S427, SMF 30B sends a PFCP Session Change Request to UPF 30C to configure the QoS flow required for MN#2. In the 3GPP Access MN#2 Forwarding Action Information IE within the Update MAR IE (see Non-Patent Document 7) included in this PFCP Session Change Request, the traffic ratio for MN#2 derived from the traffic ratio for MN#1 described in the QoS Flow Partly Setup List IE is configured. In the following step S428, UPF 30C sends a PFC P Session Change Response to SMF 30B.

[0099] In the next step S429, SMF30B recognizes that the MNs are different and sends a Namf_Communication_N1N2MessageTransfer message containing a PDU Session Resource Setup Request Transfer IE (see non-patent document 2) to AMF30A regarding the QoS flow that needs to be set up in MN#2. This PDU Session Resource Setup Request Transfer IE contains a multi-MN non-permission indication. This Namf_Communication_N1N2MessageTransfer message contains the MN identifier set to MN#2. SMF30B simultaneously sends a PDU Session Change Command to UE20 within this Namf_Communication_N1N2MessageTransfer message. This PDU Session Change Command contains an ATSSS Container IE. SMF30B sets the QoS flow distribution split information between MN#1 and MN#2 in this ASSSS Container IE (see non-patent document 8).

[0100] Figure 9 This is a sequence diagram illustrating Example (3) of the PDU session establishment process according to an embodiment of the present invention. In the following step S430, AMF 30A compares the MN identifier (MN#2) received from SMF 30B with the locally stored MN-level terminal contexts. As a result of this comparison, AMF 30A recognizes that MN#2 corresponds to RAN node 10B.

[0101] In the following step S431, the AMF 30A transmits a PDU Session Resource Setup Request, including the received PDU Session Resource Setup Request Transfer IE and the PDU Session Change Command message. This PDU Session Resource Setup Request includes the newly defined partner RAN node. This partner RAN Node IE can be the Global RANNode ID or RAT category of the RAN node 10A. This PDU Session Resource Setup Request includes all or part of the terminal radio capabilities, the remaining terminal radio capabilities, and the remaining terminal radio resources within each MN-level terminal context corresponding to the MN identifier set to MN#1.

[0102] In the following step S432, the RAN node 10B establishes a QoS flow with the UE 20, taking into account all or part of the terminal radio capabilities, the remaining terminal radio capabilities, and the remaining terminal radio resources received in step S431. Simultaneously, the RAN node 10B forwards a PDU session change command to the UE 20 (see Non-Patent Document 5). In the following step S433, the RAN node 10B uses the ATSSS container IE to set QoS-related in-terminal rules (see Non-Patent Document 5).

[0103] In the next step S434, the RAN node 10B sends a message including a PDU Session Resource Setup Response Transfer IE (see Non-Patent Document 5) to the AMF 30A. The message sent to the AMF 30A is a PDU Session Resource Setup Response, which includes the remaining terminal radio capabilities (i.e., the terminal radio capabilities available to the RAN node 10A) and the remaining terminal radio resources (i.e., the terminal radio resources available to the RAN node A).

[0104] In the following step S435, the AMF 30A stores the remaining terminal radio capabilities and remaining terminal radio resources in the respective MN-level terminal contexts corresponding to the MN identifier set as MN#2. In the following step S436, the AMF 30A sends a UE context change request (see Non-Patent Document 2) to the RAN node 10A. This UE context change request includes the remaining terminal radio capabilities and remaining terminal radio resources in the respective MN-level terminal contexts corresponding to the MN identifier set as MN#2.

[0105] In the next step S437, AMF 30A sends an Nsmf_PDUSession_UpdateSMContext Request (see Non-Patent Document 5) including the received PDU Session Resource Setup Response Transfer IE to SMF 30B. This Nsmf_PDUSession_UpdateSMContext Request message includes the MN identifier set to MN#2.

[0106] In the next step S438, SMF 30B sends a PFCP session change request to UPF 30C to set the TEID of MN#2. In the next step S439, UPF 30C sends a PFCP session change response to SMF 30B.

[0107] Furthermore, regarding the handover procedure, the RAN node 10A may also consider measurement reports, RRM information, partner RAN nodes, the partner RAN node's remaining terminal radio capabilities and remaining terminal radio resources, and RAN configuration information acquired from OAM to determine the handover destination (see Non-Patent Document 10). For example, by considering the partner RAN node's RAN type or RAT, a handover can be performed in which one of the two MNs belongs to an NG-RAN and the other to a next-generation RAN. Furthermore, the mechanism for ensuring this structure during cell selection may also depend on the terminal's installation.

[0108] According to the above-described embodiment, dual MNs using different RATs can be configured, and communication between the dual MNs can be performed in consideration of each other's remaining radio resources.

[0109] That is, in a wireless communication system in which both base stations operate as master nodes, wireless resource allocation can be performed.

[0110] (Device Structure)

[0111] Next, we will describe the functional configuration examples of base station 10, network node 30, and terminal 20 that implement the above-described processes and operations. Base station 10, network node 30, and terminal 20 each include the functions required to implement the above-described embodiments. However, base station 10, network node 30, and terminal 20 may each include only a portion of the functions described in the embodiments.

[0112] <Base Station 10 and Network Node 30>

[0113] Figure 10 1 is a diagram showing an example of the functional configuration of the base station 10 and the network node 30. Figure 10 As shown, the base station 10 includes a transmitting unit 110 , a receiving unit 120 , a setting unit 130 , and a control unit 140 . Figure 10 The functional structure shown is merely an example. As long as the operations involved in the embodiments of the present invention can be implemented, the functional divisions and names of the functional units may be arbitrary. Furthermore, the network node 30 may have the same functional structure as the base station 10. Furthermore, a network node 30 having multiple different functions in the system architecture may also be composed of multiple network nodes 30 separated by function.

[0114] The transmitter 110 includes a function for generating a signal to be transmitted to the terminal 20 or another network node 30 and transmitting the signal via wired or wireless means. The receiver 120 includes a function for receiving various signals transmitted from the terminal 20 or another network node 30 and for obtaining, for example, higher-layer information from the received signals. A communication unit including the transmitter 110 and the receiver 120 may also be configured.

[0115] The setting unit 130 stores pre-set setting information and various setting information sent to the terminal 20 in a storage device, and reads out the setting information from the storage device as needed. The content of the setting information is, for example, information related to the dual MN configuration.

[0116] As described in the embodiments, the control unit 140 performs processing related to communication within the network. Furthermore, the control unit 140 performs processing related to communication based on a dual MN configuration. Furthermore, the control unit 140 performs processing related to communication with the terminal 20. The functional units related to signal transmission within the control unit 140 may be included in the transmitter 110, while the functional units related to signal reception within the control unit 140 may be included in the receiver 120.

[0117] <Terminal 20>

[0118] Figure 11 2 is a diagram showing an example of the functional structure of the terminal 20. Figure 11 As shown, the terminal 20 includes a transmitting unit 210 , a receiving unit 220 , a setting unit 230 , and a control unit 240 . Figure 11 The functional structure shown is only an example. As long as the operations involved in the embodiment of the present invention can be implemented, the functional divisions and names of the functional units can be arbitrary. The communication device as the resource holder 20 can also have the same functional structure as the terminal 20.

[0119] The transmitter 210 generates a transmission signal based on the transmission data and wirelessly transmits the transmission signal. The receiver 220 wirelessly receives various signals and obtains higher-layer signals from the received physical layer signals. Furthermore, the receiver 220 has the function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, or reference signals transmitted from the network node 30. A communication unit including the transmitter 210 and the receiver 220 may also be configured.

[0120] The configuration unit 230 stores various configuration information received by the receiving unit 220 from the network node 30 in a storage device and reads it from the storage device as needed. In addition, the configuration unit 230 also stores pre-set configuration information. The configuration information includes, for example, information related to the dual MN configuration.

[0121] As described in the embodiment, the control unit 240 performs processing related to communication in the network. Functional units related to signal transmission in the control unit 240 may be included in the transmitter 210, and functional units related to signal reception in the control unit 240 may be included in the receiver 220.

[0122] (Hardware Structure)

[0123] The block diagram used in the description of the above embodiment ( Figure 10 and Figure 11 ) shows blocks in functional units. These functional blocks (structural parts) are implemented by any combination of at least one of hardware and software. In addition, there is no particular limitation on the implementation method of each functional block. That is, each functional block can be implemented using a device that is physically or logically combined, or it can be implemented by connecting two or more physically or logically separated devices directly or indirectly (for example, using wired or wireless connections) and using these multiple devices. The functional block can also be implemented by combining software with the above-mentioned one device or the above-mentioned multiple devices.

[0124] Functionally, these include, but are not limited to, judging, deciding, determining, calculating, calculating, processing, deriving, investigating, searching, confirming, receiving, sending, outputting, accessing, resolving, selecting, choosing, establishing, comparing, assuming, expecting, considering, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assigning. For example, a functional block (structural unit) that enables the transmission function is called a transmitting unit or a transmitter. In short, as described above, there is no particular limitation on the implementation method.

[0125] For example, the network node 30 , the terminal 20 , and the like in one embodiment of the present disclosure may also function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 12 This figure shows an example of the hardware structure of a base station 10 and a terminal 20 according to one embodiment of the present disclosure. The network node 30 may also have the same hardware structure as the base station 10. The base station 10 and the terminal 20 described above may also be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

[0126] In the following description, the term "device" can be replaced with "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and the terminal 20 may include one or more of the devices shown in the figures, or may exclude some of the devices.

[0127] The various functions in the base station 10 and the terminal 20 are implemented by reading predetermined software (programs) into hardware such as the processor 1001 and the storage device 1002, so that the processor 1001 performs calculations, controls the communication of the communication device 1004, or controls at least one of the reading and writing of data in the storage device 1002 and the auxiliary storage device 1003.

[0128] Processor 1001 controls the entire computer by, for example, executing an operating system. Processor 1001 may also be comprised of a central processing unit (CPU) including interfaces with peripheral devices, a control device, a computing device, registers, and the like. For example, control unit 140 and control unit 240 described above may also be implemented by processor 1001.

[0129] Furthermore, the processor 1001 reads a program (program code), a software module, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 to the storage device 1002, and performs various processes accordingly. As a program, a program that causes the computer to execute at least a part of the operations described in the above embodiments is used. For example, Figure 10 The control unit 140 of the base station 10 shown may also be implemented by a control program stored in the storage device 1002 and executed in the processor 1001. Figure 11 The control unit 240 of the terminal 20 shown can also be implemented by a control program stored in the storage device 1002 and executed by the processor 1001. Regarding the various processes described above, although they are described as being executed by a single processor 1001, they can also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 can also be implemented on one or more chips. Furthermore, the program can be transmitted from a network via a telecommunications line.

[0130] The storage device 1002 is a computer-readable recording medium and may be composed of, for example, at least one of ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), and RAM (Random Access Memory). The storage device 1002 may also be referred to as a register, cache, or main memory (main storage device). The storage device 1002 can store executable programs (program code), software modules, and the like for implementing the communication method according to one embodiment of the present disclosure.

[0131] The auxiliary storage device 1003 is a computer-readable recording medium and may be composed of, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a floppy disk, a magneto-optical disk (e.g., a compact disc, a digital versatile disc, a Blu-ray (registered trademark) disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a Floppy (registered trademark) disk, a magnetic stripe, and the like. The aforementioned storage medium may be, for example, another appropriate medium such as a database or a server that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0132] Communication device 1004 is hardware (a transceiver) used to communicate between computers via at least one of a wired network and a wireless network. It is also referred to as a network device, network controller, network card, or communication module. Communication device 1004 may include, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, communication device 1004 may also implement a transceiver antenna, an amplifier, a transceiver, a transmission path interface, and the like. The transceiver may also be implemented with the transmitter and receiver physically or logically separate.

[0133] The input device 1005 is an input device that receives input from the outside (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to the outside (e.g., a display, speaker, LED light, etc.). Alternatively, the input device 1005 and the output device 1006 may be integrally formed (e.g., a touch panel).

[0134] Furthermore, the processor 1001, the storage device 1002, and other devices are connected via a bus 1007 for communicating information. The bus 1007 may be configured using a single bus or different buses for different devices.

[0135] Furthermore, the base station 10 and the terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array), and may implement some or all of the functional blocks using this hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0136] Figure 13 2001 shows a structural example of a vehicle. Figure 13 As shown, vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. The various forms and embodiments described in this disclosure may also be applied to a communication device mounted on vehicle 2001, for example, communication module 2013.

[0137] The driving unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also referred to as a steering wheel) and is configured to steer at least one of the front wheels and the rear wheels based on the user's operation of the steering wheel.

[0138] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals from various sensors 2021 to 2029 included in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be referred to as an ECU (Electronic Control Unit).

[0139] As signals from various sensors 2021 to 2029, there are current signals from the current sensor 2021 that monitors the current of the motor, speed signals of the front and rear wheels obtained by the speed sensor 2022, air pressure signals of the front and rear wheels obtained by the air pressure sensor 2023, vehicle speed signals obtained by the vehicle speed sensor 2024, acceleration signals obtained by the acceleration sensor 2025, accelerator pedal depression amount signals obtained by the accelerator pedal sensor 2029, brake pedal depression amount signals obtained by the brake pedal sensor 2026, shift lever operation signals obtained by the shift lever sensor 2027, detection signals for detecting obstacles, vehicles, pedestrians, etc. obtained by the object detection sensor 2028, etc.

[0140] Information service unit 2012 is comprised of various devices, such as a car navigation system, audio system, speakers, television, and radio, that provide (output) various types of information, including driving information, traffic information, and entertainment information, and one or more ECUs that control these devices. Information service unit 2012 utilizes information obtained from external devices via communication module 2013 and other means to provide various multimedia information and services to the occupants of vehicle 2001. Information service unit 2012 may include input devices (e.g., keyboard, mouse, microphone, switches, buttons, sensors, touch panel, etc.) that receive external input, and output devices (e.g., display, speaker, LED light, touch panel, etc.) that provide external output.

[0141] Driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents or reducing the driver's driving burden, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioners (such as GNSS), map information (such as high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyroscope systems (such as IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, and one or more ECUs that control these devices. In addition, driving assistance system unit 2030 sends and receives various information via communication module 2013 to implement driving assistance functions or autonomous driving functions.

[0142] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 can transmit and receive data via the communication port 2033 with the microprocessor 2031, memory (ROM, RAM) 2032, and sensors 2021 to 29 provided in the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, and electronic control unit 2010.

[0143] The communication module 2013 is controlled by the microprocessor 2031 of the electronic control unit 2010 and is a communication device capable of communicating with external devices. For example, various information can be sent and received with the external device via wireless communication. The communication module 2013 can be located inside or outside the electronic control unit 2010. The external device can also be, for example, a base station or a mobile station.

[0144] The communication module 2013 may also transmit at least one of the signals input to the electronic control unit 2010 from the various sensors 2021-2028, information obtained based on the signals, and information based on external (user) input obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc. may also be referred to as an input unit that receives input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above input.

[0145] The communication module 2013 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from external devices and displays it on the information service unit 2012 included in the vehicle 2001. The information service unit 2012 can also be referred to as an output unit that outputs information (for example, outputs information to a display, speaker, or other device based on the PDSCH received by the communication module 2013 (or data / information decoded from the PDSCH)). In addition, the communication module 2013 stores various information received from external devices in the memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 can also control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, gear lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021 to 2029, and other components included in the vehicle 2001.

[0146] (Summary of Implementation Methods)

[0147] As described above, according to an embodiment of the present invention, a network node is provided, comprising: a communication unit that receives a registration request including information indicating the use of two master nodes from a terminal via a RAN node, the RAN being a radio access network; and a control unit that maintains two terminal contexts for each master node, the control unit maintaining a master node identifier, remaining terminal wireless capabilities, and remaining terminal wireless resources corresponding to the RAN node in the terminal context of each master node, the control unit deriving two CM states of the terminal based on the terminal context of each master node, the CM being connection management, the communication unit notifying the other of the two master nodes of the remaining terminal wireless capabilities and remaining terminal wireless resources included in the terminal context of each master node, which correspond to one of the two master nodes.

[0148] The above configuration enables dual MNs using different RATs to be configured, and communication between the two MNs can be performed taking into account the remaining radio resources of each other. In other words, radio resources can be allocated in a wireless communication system where both base stations operate as master nodes.

[0149] The communication unit receives the remaining terminal wireless capabilities and remaining terminal wireless resources available to the other of the two master nodes from one of the two master nodes. With this structure, it is possible to configure dual MNs using different RATs and perform communication based on the dual MNs taking into account each other's remaining wireless resources.

[0150] The communication unit receives all or part of the terminal's wireless capabilities from one of the two master nodes. With this configuration, dual MNs using different RATs can be configured, and communication between the dual MNs can be performed in consideration of each other's remaining wireless resources.

[0151] The control unit stores all or part of the terminal's wireless capabilities in the terminal context of the entire terminal. This configuration enables the construction of dual MNs using different RATs, each of which can perform communication based on the dual MNs while taking into account the remaining wireless resources of the other.

[0152] Furthermore, according to an embodiment of the present invention, a communication method is provided, in which a network node performs the following steps: receiving a registration request including information indicating the use of two master nodes from a terminal via a RAN node, where the RAN is a radio access network; maintaining two terminal contexts for each master node; maintaining in the terminal context of each master node a master node identifier corresponding to the RAN node, a global RAN node identifier corresponding to the RAN node, an identifier for identifying the terminal on an NG interface within the RAN node, an identifier for identifying the terminal on an NG interface within the AMF, remaining terminal radio capabilities, and remaining terminal radio resources, where the NG is next generation, and the AMF is an access and mobility management function; deriving two CM states of the terminal based on the terminal context of each master node, where the CM is connection management, and notifying the other of the two master nodes of the remaining terminal radio capabilities and remaining terminal radio resources corresponding to one of the two master nodes and included in the terminal context of each master node.

[0153] The above configuration enables dual MNs using different RATs to be configured, and communication between the two MNs can be performed taking into account the remaining radio resources of each other. In other words, radio resources can be allocated in a wireless communication system where both base stations operate as master nodes.

[0154] (Supplementary Implementation Methods)

[0155] The above describes the embodiments of the present invention, but the disclosed invention is not limited to these embodiments. Those skilled in the art will appreciate various variations, modifications, alternatives, and replacements. Specific numerical examples are used to facilitate understanding of the invention, but unless otherwise specified, these numerical values ​​are merely examples, and any appropriate value may be used. The distinction between items in the above description is not essential to the present invention. Matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as there is no conflict). The boundaries of functional units or processing units in functional block diagrams do not necessarily correspond to the boundaries of physical components. Physically, the actions of multiple functional units may be performed by a single component, or the actions of a single functional unit may be performed by multiple components. Regarding the processing procedures described in the embodiments, the order of the processing may be reversed unless there is a conflict. For ease of explanation, the base station 10 and terminal 20 are described using functional block diagrams, but such devices may also be implemented using hardware, software, or a combination thereof. The software that operates by the processor of the base station 10 according to the embodiment of the present invention and the software that operates by the processor of the terminal 20 according to the embodiment of the present invention can also be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server and other appropriate storage media.

[0156] In addition, the notification of information is not limited to the form / implementation method described in the present disclosure, and other methods may also be used. For example, the notification of information can be implemented through physical layer signaling (for example, DCI (Downlink Control Information), UCI (Uplink Control Information)), high-layer signaling (for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals or a combination thereof. In addition, RRC signaling may also be referred to as an RRC message, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

[0157] Each form / embodiment described in the present disclosure may also be applied to LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6G (6th generation mobile communication system), xG (xth generation mobile communication system) (xG (xG is, for example, an integer or a decimal)), FRA (Future Radio Access), NR (New Radio), NX (New Radio Access), FX (Future Generation Radio Access), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IE At least one of IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), systems using other appropriate systems, and next-generation systems extended, modified, generated, or specified therefrom. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G) may also be employed.

[0158] The processing procedures, timings, and flows of each form / implementation described in this specification may be performed in different orders unless there is any inconsistency. For example, the methods described in this disclosure use an illustrative order to present the elements of various steps, but are not limited to the specific order presented.

[0159] In this specification, specific operations performed by base station 10 may also be performed by its upper node depending on the situation. In a network consisting of one or more network nodes including base station 10, various operations performed to communicate with terminal 20 can be performed by at least one of base station 10 and other network nodes other than base station 10 (e.g., MME or S-GW, but not limited thereto). While the above example illustrates a single other network node other than base station 10, the other network node may also be a combination of multiple other network nodes (e.g., MME and S-GW).

[0160] The information or signals described in this disclosure can be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), and can also be input or output via multiple network nodes.

[0161] Input or output information can be stored in a specific location (e.g., memory) or managed using a management table. Input or output information can be overwritten, updated, or appended. Output information can also be deleted. Input information can also be sent to other devices.

[0162] The determination in the present disclosure may be performed using a value represented by one bit (0 or 1), a Boolean value (Boolean: true or false), or a comparison of numerical values ​​(for example, comparison with a predetermined value).

[0163] Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by other names, shall be interpreted broadly to refer to instructions, sets of instructions, code, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, execution threads, procedures, functions, etc.

[0164] Furthermore, software, commands, information, and the like may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of a wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and a wireless technology (infrared, microwave, etc.), at least one of these wired and wireless technologies is included within the definition of a transmission medium.

[0165] The information, signals, and the like described in this disclosure may also be represented using any of a variety of different technologies. For example, data, commands, instructions, information, signals, bits, symbols, chips, and the like that may be referred to in the entire description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination thereof.

[0166] In addition, the terms used in this disclosure and those necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may also be referred to as a carrier frequency, a cell, a frequency carrier, etc.

[0167] As used in this disclosure, the terms "system" and "network" may be used interchangeably.

[0168] In addition, the information, parameters, etc. described in this disclosure may be represented by absolute values, relative values ​​relative to a predetermined value, or other corresponding information. For example, wireless resources may also be indicated by an index.

[0169] The names used for the above parameters are not restrictive in any way. Furthermore, the formulas for using these parameters may sometimes differ from those explicitly disclosed in this disclosure. Since various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any appropriate name, the names assigned to these channels and information elements are not restrictive in any way.

[0170] In this disclosure, terms such as "base station (BS)," "wireless base station," "base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" are used interchangeably. Base stations are also sometimes referred to as macrocells, small cells, femtocells, and picocells.

[0171] A base station can accommodate one or more (for example, three) cells. When a base station accommodates multiple cells, the base station's overall coverage area can be divided into multiple smaller areas, each of which can also provide communication services through a base station subsystem (for example, a small base station for indoor use (RRH: Remote Radio Head)). Terms such as "cell" or "sector" refer to a portion or the entire coverage area of ​​at least one of the base station and base station subsystem that provide communication services within the coverage area.

[0172] In the present disclosure, the base station sending a message to the terminal may also be replaced by the base station instructing the terminal to perform information-based control / action.

[0173] In the present disclosure, terms such as “mobile station (MS)”, “user terminal (user terminal)”, “user equipment (UE)”, and “terminal” may be used interchangeably.

[0174] For mobile stations, those skilled in the art sometimes also use the following terms to refer to them: subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client or some other appropriate terms.

[0175] At least one of the base station and the mobile station can be called a transmitting device, a receiving device, a communication device, etc. In addition, at least one of the base station and the mobile station can also be a device mounted on a mobile body, the mobile body itself, etc. The mobile body refers to a movable object, and the moving speed is arbitrary. In addition, of course, it also includes the case where the mobile body is stopped. The mobile body includes, for example, vehicles, transport vehicles, cars, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, carts, rickshaws, ships (ships and other watercraft), airplanes, rockets, artificial satellites, drones (registered trademarks), multicopters, quadcopters, hot air balloons and objects mounted on them, and is not limited to these. In addition, the mobile body can also be a mobile body that moves autonomously based on an operation instruction. The mobile body can be a means of transportation (for example, a car, airplane, etc.), a mobile body that moves in an unmanned manner (for example, a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Furthermore, at least one of the base station and the mobile station may include a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0176] In addition, the base station in the present disclosure can also be replaced by a user terminal. For example, regarding a structure in which the communication between the base station and the user terminal is replaced by the communication between multiple terminals 20 (for example, it can also be called D2D (Device-to-Device: device to device), V2X (Vehicle-to-Everything: vehicle to everything system), etc.), the various forms / implementations of the present disclosure can also be applied. In this case, it can also be set as a structure in which the terminal 20 has the functions of the above-mentioned base station 10. In addition, terms such as "uplink" and "downlink" can also be replaced by terms corresponding to inter-terminal communication (for example, "side"). For example, uplink channels, downlink channels, etc. can also be replaced by side channels.

[0177] Likewise, the user terminal in the present disclosure may be replaced by a base station. In this case, the base station may also have the functions of the user terminal described above.

[0178] As used in this disclosure, terms such as “determining” and “determining” sometimes encompass a variety of actions. For example, “determining” and “judging” may include considering matters such as judging, calculating, computing, processing, deriving, investigating, looking up, searching, or inquiring (e.g., searching a table, database, or other data structure), or ascertaining as matters that have been “determined” or “determined.” Furthermore, “determining” and “receiving” (e.g., receiving information), transmitting (e.g., sending information), inputting, outputting, or accessing (e.g., accessing data in a memory) as matters that have been “determined” or “determined.” Furthermore, “determining” and “resolving” may include matters such as selecting, choosing, establishing, or comparing. That is, "judgment" and "decision" can include matters that are considered to have "judged" or "decided" certain actions. In addition, "judgment (decision)" can also be replaced by "assuming (assuming)", "expecting (expecting)", "considering (considering)", etc.

[0179] The terms "connected", "coupled" or all variations of these terms are intended to indicate any direct or indirect connection or combination between two or more elements, and may include situations where one or more intermediate elements exist between two elements that are "connected" or "coupled" to each other. The combination or connection between elements may be a physical combination or connection, a logical combination or connection, or a combination of these. For example, "access" may be used instead of "connection". As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables and printed electrical connections, and as some non-limiting and non-inclusive examples, electromagnetic energy having wavelengths in the wireless frequency domain, microwave region and light (visible and invisible) region may be used to "connect" or "couple" to each other.

[0180] The reference signal may be referred to as RS (Reference Signal) for short, or may be called a pilot according to the applicable specification.

[0181] The phrase “based on” used in this disclosure does not mean “based only on.” Unless explicitly stated otherwise, the phrase “based on” does not mean “based only on.” In other words, the phrase “based on” means both “based only on” and “based at least on.”

[0182] Any reference to an element using the terms "first," "second," etc., as used in this disclosure, does not necessarily limit the number or order of these elements. These terms can be used as a convenient way to distinguish between two or more elements in this disclosure. Therefore, a reference to a first element and a second element does not mean that only two elements can be used or that the first element must precede the second element in some form.

[0183] The “unit” in the configuration of each of the above-mentioned devices may be replaced with a “section,” “circuit,” “device,” or the like.

[0184] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, the term "or" used in this disclosure does not mean an exclusive OR.

[0185] In the present disclosure, when an article is added by translation, such as a, an, and the in English, the present disclosure may also include cases where the noun following the article is in a plural form.

[0186] In this disclosure, the phrase "A and B are different" may also mean "A and B are different from each other." Alternatively, the phrase may also mean "A and B are each different from C." Terms such as "separate" and "combined" may also be interpreted in the same way as "different."

[0187] The various forms / implementations described in this disclosure may be used individually or in combination, or may be switched as the execution progresses. Furthermore, notification of scheduled information is not limited to being performed explicitly (e.g., a notification of "Yes X") but may also be performed implicitly (e.g., not notifying the scheduled information).

[0188] While the present disclosure has been described in detail above, it should be clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in various modifications and variations without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is for illustrative purposes only and does not have any limiting meaning on the present disclosure.

[0189] Description of labels

[0190] 10 base stations

[0191] 110 Sending Department

[0192] 120 Receiving Department

[0193] 130 Setting Department

[0194] 140 Control Department

[0195] 20 terminals

[0196] 210 Sending Department

[0197] 220 Receiving Department

[0198] 230 Setting Department

[0199] 240 Control Department

[0200] 30 network nodes

[0201] 1001 processor

[0202] 1002 storage device

[0203] 1003 auxiliary storage device

[0204] 1004 communication device

[0205] 1005 Input Device

[0206] 1006 output device

Claims

1. A network node, comprising: a communication unit that receives a registration request including information indicating that two master nodes are used from a terminal via a RAN node, the RAN being a radio access network; and A control unit that maintains two terminal contexts for each master node, The control unit stores the master node identifier, remaining terminal radio capabilities, and remaining terminal radio resources corresponding to the RAN node in the terminal context of each master node. The control unit derives two CM states of the terminal based on the terminal context of each master node, wherein the CM is a connection management state. The communication unit notifies the other of the two master nodes of the remaining terminal wireless capabilities and remaining terminal wireless resources corresponding to one of the two master nodes and included in the terminal context of each master node.

2. The network node according to claim 1, wherein: The communication unit receives, from one of the two master nodes, remaining terminal wireless capabilities and remaining terminal wireless resources that can be used by the other of the two master nodes.

3. The network node according to claim 1, wherein: The communication unit receives all or part of the terminal wireless capabilities from one of the two master nodes. The network node according to claim 3 , wherein: The control unit maintains all or part of the terminal wireless capabilities within the terminal context of the entire terminal.

5. A communication method, comprising: performing the following steps by a network node: receiving, from a terminal via a RAN node, a registration request including information indicating use of two primary nodes, the RAN being a radio access network; Maintain two terminal contexts for each master node; maintaining, in the terminal context of each master node, a master node identifier, remaining terminal radio capabilities, and remaining terminal radio resources corresponding to the RAN node; Based on the terminal context of each master node, deriving two CM states of the terminal, the CM being connection management; and The remaining terminal wireless capabilities and remaining terminal wireless resources corresponding to one of the two master nodes and included in the terminal context of each master node are notified to the other of the two master nodes.

Images