wireless base station

Abstract

This wireless base station receives a configuration indication from a radio resource control layer. If the configuration indication is included in a particular inter-node message, the wireless base station assumes that the configuration indication is from the radio resource control layer of a secondary cell group and a radio bearer, and if another configuration indication differing from the configuration indication is included in the inter-node message, the wireless base station assumes that the configuration indication is from the radio resource control layer of the secondary cell group.

Description

[Technical Field]

[0001] The present disclosure relates to a radio base station that supports a procedure for changing a secondary cell (secondary node). [Background technology]

[0002] The 3rd Generation Partnership Project (3GPP) has developed specifications for the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.

[0003] In 3GPP Release-15, in the secondary node (SN) change procedure (SN Change - MN initiated) in E-UTRA-NR Dual Connectivity (EN-DC), when a target secondary node (T-SN) configures the radio resource control layer (RRC), it can send an inter-node message (SgNB Addition Request Acknowledge) with the configuration indication (RRC config indication) set to full config. to the master node (MN) (Non-Patent Document 1).

[0004] Based on the RRC config indication (full config.), the radio base station that constitutes the MN releases and adds the configuration related to the secondary cell group (SCG) to the terminal (User Equipment, UE).

[0005] In addition, in the SN modification procedure (SN initiated with MN involvement) in the EN-DC, if the target Distributed Unit (DU) triggers full configuration (full config.), the SN can now send an inter-node message (SgNB Modification Required / SgNB Modification Request Acknowledge) with the RRC config indication set to full config. to the MN. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] 3GPP TS 37.340 V15.11.0, 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and NR; Multi-connectivity; Stage 2 (Release 15), 3GPP, December 2020 Summary of the Invention

[0007] As described above, the RRC config indication (full config.) is used in two types of SN change procedures, but the RRC config indication may refer to the RRC configuration of the SCG or the RRC configuration of the SCG and radio bearer. Therefore, even if the RRC config indication is notified, the radio base station (MN) may not be able to configure the appropriate RRC.

[0008] Therefore, the following disclosure has been made in consideration of such circumstances, and aims to provide a radio base station that can perform appropriate configuration in accordance with a configuration indication in a radio resource control layer.

[0009] Therefore, the following disclosure has been made in consideration of such circumstances, and aims to provide a radio base station that can perform appropriate configuration in accordance with a configuration indication in a radio resource control layer.

[0010] One aspect of the present disclosure is a radio base station (e.g., eNB100A) that includes a receiving unit (RRC processing unit 120) that receives a configuration indication of a radio resource control layer, and a control unit (control unit 140) that, when the configuration indication is included in a specific inter-node message, assumes that the configuration indication is a configuration indication in the radio resource control layer of a secondary cell group and a radio bearer, and, when a different configuration indication different from the configuration indication is included in the inter-node message, assumes that the configuration indication is a configuration indication in the radio resource control layer of the secondary cell group.

[0011] One aspect of the present disclosure is a radio base station (e.g., eNB100A) that includes a receiving unit (RRC processing unit 120) that receives a configuration indication of a radio resource control layer, and a control unit (control unit 140) that assumes that the configuration indication is a configuration indication in the radio resource control layer of a secondary cell group and a radio bearer when the configuration indication is included in a specific inter-node message, and that the control unit assumes that the configuration indication is a configuration indication in the radio resource control layer of the secondary cell group when the inter-node message includes a specific information element.

[0012] One aspect of the present disclosure is a radio base station (e.g., eNB100A) that includes a receiving unit (RRC processing unit 120) that receives a configuration indication of a radio resource control layer, and a control unit (control unit 140) that, if the configuration indication is included in a first inter-node message, assumes that it is a configuration indication in the radio resource control layer of a secondary cell group and a radio bearer, and, if the configuration indication is included in a second inter-node message, assumes that it is a configuration indication in the radio resource control layer of a secondary cell group, wherein the control unit, if the first inter-node message or the second inter-node message includes a specific information element, assumes that it is a configuration indication in the radio resource control layer of the secondary cell group and a radio bearer, and, if the first inter-node message or the second inter-node message does not include the specific information element, assumes that it is a configuration indication in the radio resource control layer of the secondary cell group. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing the overall schematic configuration of a wireless communication system 10. As shown in FIG. [Figure 2] FIG. 2 is a functional block diagram of the eNB 100A. [Figure 3] FIG. 3 is a functional block diagram of the UE 200. [Figure 4] FIG. 4 is a diagram showing an example of a sequence of an MN-initiated inter-SN SCG change. [Figure 5] FIG. 5 is a diagram showing an example of a sequence of an SN Modification procedure - SN initiated with MN involvement. [Figure 6] FIG. 6 is a diagram showing an example of specific actions of the MN according to the second operation example. [Figure 7] FIG. 7 is a diagram showing an example of a SgNB Addition Request Acknowledge specification. [Figure 8]FIG. 8 is a diagram showing an example of a SgNB Modification Request Acknowledge specification. [Figure 9] FIG. 9 is a diagram showing an example of a definition of the RRC config indication. [Figure 10] FIG. 10 is a diagram illustrating an example of the hardware configuration of the eNB100A, the gNB100B, and the UE200. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0015] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0016] (1) Overall configuration of wireless communication system 1 is a schematic diagram of the overall configuration of a wireless communication system 10 according to this embodiment. The wireless communication system 10 is a wireless communication system conforming to Long Term Evolution (LTE) and 5G New Radio (NR). Note that LTE may also be called 4G, and NR may also be called 5G. The wireless communication system 10 may also be a wireless communication system conforming to a scheme called Beyond 5G, 5G Evolution, or 6G.

[0017] LTE and NR may be interpreted as radio access technologies (RATs), and in this embodiment, LTE may be referred to as the first radio access technology, and NR may be referred to as the second radio access technology.

[0018] The wireless communication system 10 includes an Evolved Universal Terrestrial Radio Access Network 20 (hereinafter, E-UTRAN 20) and a Next Generation-Radio Access Network 30 (hereinafter, NG RAN 30). The wireless communication system 10 also includes a terminal 200 (hereinafter, UE 200, User Equipment).

[0019] The E-UTRAN 20 includes an eNB 100A, which is a radio base station conforming to LTE. The NG RAN 30 includes a gNB 100B, which is a radio base station conforming to 5G (NR). The E-UTRAN 20 may include a Mobility Management Entity (MME) and a Serving Gateway (S-GW). The NG RAN 30 may also be connected to a User Plane Function, which is included in the 5G system architecture and provides user plane functions. The E-UTRAN 20 and the NG RAN 30 (which may be the eNB 100A or the gNB 100B) may simply be referred to as a network.

[0020] The eNB100A, gNB100B and UE200 are capable of supporting carrier aggregation (CA) using multiple component carriers (CCs), and dual connectivity for simultaneously transmitting component carriers between multiple NG-RAN nodes and the UE.

[0021] The eNB100A, the gNB100B, and the UE200 perform wireless communication via a radio bearer, specifically, a Signaling Radio Bearer (SRB) or a DRB Data Radio Bearer (DRB).

[0022] In this embodiment, Multi-Radio Dual Connectivity (MR-DC) in which the eNB100A constitutes the master node (MN) and the gNB100B constitutes the secondary node (SN), specifically E-UTRA-NR Dual Connectivity (EN-DC), may be implemented, or NR-E-UTRA Dual Connectivity (NE-DC) in which the gNB100B constitutes the MN and the eNB100A constitutes the SN may be implemented, or NR-NR Dual Connectivity (NR-DC) in which the gNB constitutes both the MN and the SN may be implemented.

[0023] In this way, UE200 supports dual connectivity connecting to eNB100A and gNB100B.

[0024] The eNB 100A is included in a master cell group (MCG), and the gNB 100B is included in a secondary cell group (SCG). That is, the gNB 100B is an SN included in the SCG. The SN may be distinguished into a source SN (S-SN), which is the SN from which the SN is added or changed, and a target SN (T-SN), which is the SN to which the SN is added or changed.

[0025] The eNB100A and the gNB100B may be referred to as radio base stations or network devices. Furthermore, the eNB100A and the gNB100B may be configured with a CU (Central Unit) and a DU (Distributed Unit). Multiple DUs may be connected to the CU, and the DU may have radio physical layer functions such as an antenna port.

[0026] Furthermore, the wireless communication system 10 may support conditional addition or change of a Primary SCell (PSCell). A PSCell is a type of secondary cell. A PSCell means a Primary SCell (secondary cell), and may be interpreted as corresponding to any SCell among multiple SCells.

[0027] The secondary cell may be read as a secondary node (SN) or a secondary cell group (SCG). The conditional PSCell addition / change can realize efficient and rapid addition or change of a secondary cell.

[0028] The conditional PSCell addition / change may be interpreted as a simplified conditional secondary cell addition / change procedure. The conditional PSCell addition / change may mean at least one of addition and change of a SCell.

[0029] Furthermore, the wireless communication system 10 may support a conditional inter-SN PSCell change procedure. Specifically, at least one of an MN-initiated inter-SN SCG change, an SN-initiated inter-SN SCG change, and an SN Modification procedure may be supported. Furthermore, an intra-SN PSCell change may be supported.

[0030] Furthermore, in the wireless communication system 10, with regard to the configuration of the radio resource control layer (RRC), a full configuration (full config.) that executes almost all the configuration and a partial configuration (delta config.) that executes some of the configuration may be defined.

[0031] In the full config., all dedicated radio settings that are currently configured may be released / cleared, except for the MCG's C (Cell)-RNTI and the AS (Access Stratum) security settings associated with the master key.

[0032] (2) Functional block configuration of wireless communication system Next, a description will be given of the functional block configuration of the wireless communication system 10. Specifically, the functional block configurations of the eNB 100A and the UE 200 will be described.

[0033] (2.1) eNB100A Fig. 2 is a functional block diagram of the eNB 100A. As shown in Fig. 2, the eNB 100A includes a radio communication unit 110, an RRC processing unit 120, a DC processing unit 130, and a control unit 140. Note that the gNB 100B may also have similar functions to the eNB 100A, although it differs in that it supports NR.

[0034] The wireless communication unit 110 transmits downlink signals (DL signals) conforming to LTE, and also receives uplink signals (UL signals) conforming to LTE.

[0035] The RRC processing unit 120 executes various processes in the radio resource control layer (RRC). Specifically, the RRC processing unit 120 can transmit an RRC Reconfiguration to the UE 200. Furthermore, the RRC processing unit 120 can receive an RRC Reconfiguration Complete from the UE 200, which is a response to the RRC Reconfiguration.

[0036] In this embodiment, the eNB 100A supports LTE. In this case, the name of the RRC message may be RRC Connection Reconfiguration or RRC Connection Reconfiguration Complete.

[0037] Furthermore, the RRC processing unit 120 may process inter-node messages with the gNB 100B. For example, in the procedure of MN-initiated SN change (3GPP TS37.340 Chapter 10.5.1), the RRC processing unit 120 can transmit an SgNB Modification Request to the gNB 100B (in the case of T-SN) and receive an SgNB Addition Request Acknowledge, which is a response to the SgNB Modification Request, from the gNB 100B.

[0038] Furthermore, the RRC processing unit 120 can send an SgNB Release Request to the gNB100B (in the case of an S-SN) and receive an SgNB Release Request Acknowledge, which is a response to the SgNB Release Request, from the gNB100B.

[0039] In addition, the RRC processing unit 120 can receive SgNB Modification Required from the gNB 100B and send SgNB Modification Confirm to the gNB 100B in the SN Modification procedure - SN initiated with MN involvement (3GPP TS37.340 Chapter 10.3.1).

[0040] Furthermore, the RRC processing unit 120 can send an SgNB Modification Request to the gNB 100B to provide forwarding addresses and / or security keys for the SgNB, and can receive an SgNB Modification Request Acknowledge from the gNB 100B, which is a response to the SgNB Modification Request.

[0041] In this embodiment, the inter-node message may be interpreted as a message related to a request for adding or changing an SN (which may include conditional PSCell addition / change, etc.).

[0042] Furthermore, the RRC processing unit 120 can receive an RRC configuration indication. In this embodiment, the RRC processing unit 120 may constitute a receiving unit. Specifically, the RRC processing unit 120 can receive an RRC config indication. The RRC config indication may be included as an information element (IE) in the above-mentioned inter-node message.

[0043] For example, the RRC config indication may be included in the SgNB Addition Request Acknowledge, the SgNB Modification Required, and the SgNB Modification Request Acknowledge. However, the RRC config indication may also be included in other inter-node messages transmitted from the SN, for example.

[0044] The RRC config indication may be interpreted as an indication of the RRC configuration content. The RRC config indication may indicate the type of full config. or delta config. as described above, and may include the RRC configuration content related to the SCG, SN, or SgNB.

[0045] The DC processing unit 130 performs processing related to dual connectivity, specifically, Multi-RAT Dual Connectivity (MR-DC). In this embodiment, the eNB 100A supports LTE and the gNB 100B supports NR, so the DC processing unit 130 may perform processing related to E-UTRA-NR Dual Connectivity (EN-DC). Note that, as described above, the type of DC is not limited, and may correspond to, for example, NR-E-UTRA Dual Connectivity (NE-DC) or NR-NR Dual Connectivity (NR-DC).

[0046] The DC processing unit 130 can transmit and receive messages specified in 3GPP TS37.340 and the like, and perform processing related to setting up and releasing DC between the eNB100A, the gNB100B, and the UE200.

[0047] The control unit 140 controls each functional block that configures the eNB 100 A. In particular, in this embodiment, the control unit 140 executes control related to the addition or change of a secondary node.

[0048] Specifically, when an RRC configuration indication is included in a particular inter-node message, the control unit 140 may assume that it is a configuration indication in the RRC of the SCG.

[0049] The specific inter-node message may refer to SgNB Addition Request Acknowledge, SgNB Modification Required, or SgNB Modification Request Acknowledge. The configuration indication in RRC of SCG may refer to RRC configuration of SCG config.

[0050] Alternatively, the control unit 140 may assume that an RRC configuration indication (RRC config indication) is a configuration indication in the RRC of the SCG and the radio bearer when it is included in a specific inter-node message (SgNB Addition Request Acknowledge, SgNB Modification Required, or SgNB Modification Request Acknowledge). The RRC configuration indication in the RRC of the SCG and the radio bearer may mean the RRC configuration of both the SCG config and the radio bearer config.

[0051] Alternatively, the control unit 140 may assume that the RRC config indication, if included in the first inter-node message, is a configuration indication in the radio resource control layer of the SCG and the radio bearer, and that the control unit 140 may assume that the RRC config indication, if included in the second inter-node message, is a configuration indication in the RRC of the SCG.

[0052] The first inter-node message may be, for example, an SgNB Addition Request Acknowledge, and the second inter-node message may be an SgNB Modification Request Acknowledge or an SgNBModification Required.

[0053] In addition, when an RRC config indication is included in a specific inter-node message, the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG and radio bearer, and when another RRC config indication different from the RRC config indication (for example, RRC config indication 2 (tentative name)) is included in the inter-node message, it may assume that it is an RRC config indication in the RRC of the SCG.

[0054] In addition, when an RRC config indication is included in a specific inter-node message, the control unit 140 may assume that it is a configuration indication in the RRC of the SCG and radio bearer, but when the inter-node message includes a specific information element, the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG.

[0055] Furthermore, as described above, when an RRC config indication is included in the first inter-node message, the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG and the radio bearer, and when an RRC config indication is included in the second inter-node message, the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG. However, when a specific information element (e.g., RadioBearerReleaseNotRequired (tentative name)) is included in the first inter-node message or the second inter-node message, the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG and the radio bearer, and when the specific information element is not included (absent) in the first inter-node message or the second inter-node message (including when the specific information element is included but a specific value, etc. is not set), the control unit 140 may assume that it is an RRC config indication in the RRC of the SCG.

[0056] The control unit 140 may release radio bearers terminated in the SN and provide security information to the SN based on the type of inter-node message containing the RRC config indication.

[0057] Specifically, when the control unit 140 receives an SgNB Modification Request Acknowledge or an SgNB Modification Required, it may release the DRB terminated at the SN and provide updated security information (specifically, the security key (S-KgNB)) to the SN.

[0058] Alternatively, the control unit 140 may not generate a release list for the radio bearer or may restore the packet data convergence protocol layer (PDCP) of the radio bearer terminated in the radio base station (eNB100A) based on the type of inter-node message containing the RRC config indication.

[0059] Specifically, as described above, when the RRC config indication is included in the SgNB Addition Request Acknowledge (first inter-node message), the control unit 140 assumes that it is a configuration indication in the radio resource control layer of the SCG and radio bearer, and when the RRC config indication is included in the SgNB Modification Request Acknowledge or SgNB Modification Required (second inter-node message), the control unit 140 may not generate a release list for the radio bearer or restore PDCP for the radio bearer if it assumes that it is a configuration indication in the RRC of the SCG.

[0060] Furthermore, the control unit 140 may not generate a release list for the radio bearer or may restore the PDCP of the radio bearer depending on the content of the PDCP change indication defined in the X2-AP.

[0061] The contents of the PDCP change indication may include, for example, (i) the PDCP change indication is not included in the node-to-node message, (ii) PDCP data recovery, or (iii) a security key (S-KgNB) update is required.

[0062] No generation of a release list for a radio bearer may mean "No generation of drb-to-ReleaseList," and PDCP recovery for a radio bearer may mean "PDCP recovery of MN terminated DRBs."

[0063] (2.2)UE200 3 is a functional block diagram of the UE 200. As shown in FIG. 3, the UE 200 includes a radio communication unit 210, an RRC processing unit 220, a DC processing unit 230, and a control unit 240.

[0064] The radio communication unit 210 transmits an uplink signal (UL signal) conforming to LTE or NR. The radio communication unit 210 also receives a downlink signal (DL signal) conforming to LTE or NR. That is, the UE 200 can access the eNB 100A (E-UTRAN 20) and the gNB 100B (NG RAN 30) and can support dual connectivity (specifically, EN-DC).

[0065] The RRC processing unit 220 executes various processes in the radio resource control layer (RRC). Specifically, the RRC processing unit 220 can send and receive messages in the radio resource control layer.

[0066] The RRC processing unit 220 can receive RRC Reconfiguration from the network, specifically, the E-UTRAN 20 (or the NG RAN 30). The RRC processing unit 220 can also transmit RRC Reconfiguration Complete, which is a response to the RRC Reconfiguration, to the network.

[0067] The DC processing unit 230 performs processing related to dual connectivity, specifically, MR-DC. As described above, in this embodiment, the DC processing unit 230 may perform processing related to EN-DC, but may also support NE-DC and / or NR-DC.

[0068] The DC processing unit 230 can access each of the eNB100A and the gNB100B and perform configurations at multiple layers including RRC (such as the medium access control layer (MAC), the radio link control layer (RLC), and the packet data convergence protocol layer (PDCP)).

[0069] The control unit 240 controls each functional block constituting the UE 200. In particular, in this embodiment, the control unit 240 executes control relating to addition or change of SN and control relating to RRC setting.

[0070] Specifically, the control unit 240 may add or change an SN based on an RRC message transmitted from the eNB 100A (MN) or the gNB 100B (SN). Furthermore, the control unit 240 may perform various RRC settings based on the RRC message. The RRC settings may include the full config. or delta config. described above.

[0071] (3) Operation of the wireless communication system Next, the operation of the wireless communication system 10 will be described. Specifically, the RRC setting display (RRC The operation of the wireless communication system 10 regarding the config indication will be described below.

[0072] (3.1) Examples of conventional operation and issues In the (NG)EN-DC inter SN SCG change specified in 3GPP Release-15, full config. can be specified as the RRC config indication.

[0073] Figure 4 shows an example sequence of an MN-initiated inter-SN SCG change. As shown in Figure 4, in an MN-initiated SCG (SN) change (3GPP TS37.340 Chapter 10.5.1), if a T-SN (e.g., gNB100B) triggers a full config., the RRC config indication included in the SgNB Addition Request Acknowledge may be set to the full config.

[0074] Based on the received full config. instruction, the MN (e.g., eNB 100A) instructs the UE 200 to release and add the RRC settings related to the SCG (specifically, it turns on Endc-ReleaseAndAdd, which is an RRC IE). Next, the MN releases the radio bearer, specifically, the SN terminated DRB, that is, it generates a DRB-ToReleaseList.

[0075] Also, in the (NG)EN-DC Intra-CU inter DU SCG change / Intra-SN PSCell change specified in 3GPP Release-15, full config. can be specified as the RRC config indication.

[0076] Figure 5 shows an example of the sequence of SN Modification procedure - SN initiated with MN involvement. As shown in Figure 5, when the target DU (SN) triggers full config., the RRC included in SgNB Modification Required or SgNB Modification Request Acknowledge It is additionally specified that the config indication may be set to full config.

[0077] Specifically, 3GPP TS36.423 Chapter 8.7.7.2 specifies that the (en-)gNB notifies the MeNB (MN) by including an RRC config indication IE in an SgNB Modification Request Acknowledge, and that the (en-)gNB notifies the MeNB (MN) by including an RRC config indication IE in an SgNB Modification Required.

[0078] (3.2) Example 1 However, the operation according to the above-mentioned rules is considered to have the following problems.

[0079] (Issue 1): In the (NG) EN-DC Intra-CU inter DU SCG change / Intra-SN PSCell change, an SgNB Modification Required or SgNB Modification Request Acknowledge is sent from the SN to the MN, but it is unclear which of the following meanings the RRC config indication contained in the inter-node message has.

[0080] (Option 1): RRC configuration of SCG config (Option 2): RRC configuration of both SCG config and radio bearer config (Issue 2): The RRC config indication included in the SgNB Addition Request Acknowledge has the meaning of Option 2, but the RRC config indication included in the SgNB Modification Required or SgNB Modification Request Acknowledge may have the meaning of Option 1. Therefore, even though it is the same RRC config indication, there are two different interpretations, which may hinder proper operation.

[0081] Therefore, the radio communication system 10 (MN and SN) may follow any of the following operation examples 1-1 to 1-3 regarding the handling of the RRC config indication included in the next inter-node message.

[0082] (Message between target nodes): ·SgNB Addition Request Acknowledge ·SgNB Modification Request Acknowledge SgNB Modification Required (Operation example 1-1): RRC config indication (full config.) is interpreted as the meaning of option 1 described above.

[0083] (Operation example 1-2): RRC config indication (full config.) is interpreted as the meaning of option 2 described above.

[0084] (Operation example 1-3): The RRC config indication (full config.) included in the SgNB Addition Request Acknowledge is interpreted as the meaning of option 2, and the RRC config indication (full config.) included in the SgNB Modification Request Acknowledge and SgNB Modification Required is interpreted as the meaning of option 2. config.) is interpreted as meaning option 1.

[0085] Such an operation example can solve the above-mentioned problems 1 and 2, and can realize appropriate RRC settings according to the changes in SN.

[0086] (Operation example 1-4): The conventional RRC config indication is interpreted as meaning Option 2 described above in any inter-node message, and the new RRC config indication 2 is introduced in SgNB Modification Request Acknowledge and SgNB Modification Required, and RRC config indication 2 is interpreted as meaning Option 1 described above.

[0087] (Operation example 1-5): The conventional RRC config indication is interpreted as having the meaning of Option 2 described above in any inter-node message, and if the new information element (IE) RadioBearerReleaseNotRequired (tentative name) is included (exists) in SgNB Modification Request Acknowledge or SgNB Modification Required, it is interpreted together with the conventional RRC config indication as having the meaning of Option 1 described above.

[0088] (Operation Example 1-6): The conventional RRC config indication is interpreted in the same way as in Operation Example 1-3. If the new information element (IE) RRC config of radio bearer (tentative name (full config. / delta config.)) is included (exists) in SgNB Modification Request Acknowledge or SgNB Modification Required and the IE is set to full config., it is interpreted together with the conventional RRC config indication as meaning Option 2 described above. If the IE is absent / set, it is interpreted as meaning Option 1 described above. If the IE is set to delta config., it is interpreted as meaning that the radio bearer is delta config.

[0089] Note that the operation examples 1-4 to 1-6 may be applied when the operation example 1-2 or the operation example 1-3 is not (cannot be) applied.

[0090] (3.3) Example 2 In the above-mentioned Intra-CU inter DU SCG change / Intra-SN PSCell change, the full configuration of the SN's RRC configuration (NR SCG config + SCG radio bearer config) can be notified to the MN by a combination of RRC config indication and PDCP change indication specified in the X2-AP (Application) protocol.

[0091] However, the operation of the MN changes depending on how the meaning of the RRC config indication explained in the first operation example is interpreted.

[0092] Therefore, the MN may follow either of the following operation examples 2-1 or 2-2 regarding release and addition (Endc-ReleaseAdd) for the EN-DC, depending on the interpretation of the meaning of the RRC configuration indication.

[0093] FIG. 6 shows an example of the specific actions of the MN according to the second operation example.

[0094] (Operation Example 2-1): When the interpretation of the meaning of the RRC config indication is according to Operation Example 1-2 (meaning of Option 2), when the MN receives an SgNB Modification Request Acknowledge or SgNB Modification Required containing an RRC config indication (full config.) from the SN, it may operate according to Interpretation 2 shown in Figure 6.

[0095] As shown in Figure 6, in Interpretation 2, the MN may release the DRB terminated at the SN and provide updated security information (specifically, the security key (S-KgNB)) to the SN regardless of the content of the PDCP change indication.

[0096] (Operation Example 2-2): When the meaning of the RRC config indication is interpreted according to Operation Example 1-3 (meaning of Option 1 or Option 2 depending on the type of inter-node message), when the MN receives an SgNB Modification Request Acknowledge or SgNB Modification Required containing an RRC config indication (full config.) from the SN, it may operate according to Interpretation 1 shown in Figure 6.

[0097] As shown in Figure 6, in Interpretation 1, the MN may perform no generation of a radio bearer release list (drb-to-ReleaseList), PDCP data recovery, or security key (S-KgNB) update depending on the content of the PDCP change indication.

[0098] (Operation Example 2-3): When the meaning of the RRC config indication is interpreted according to Operation Examples 1-3 to 1-6 (meaning of Option 1 or Option 2 depending on the type of inter-node message), the MN may operate according to Table 1 when it receives an SgNB Modification Request Acknowledge or SgNB Modification Required containing an RRC config indication (full config.) from the SN.

[0099] [Table 1]

[0100] Specifically, as shown in Table 1, the operation of the MN may be changed depending on the RRC config indication (traditional (existing) or new (RRC config indication2)) included in the inter-node message by the X2-AP. Also, as shown in Table 1, the operation of the MN may be changed depending on the presence of an information element (RadioBearReleaseNotRequired) included in the inter-node message.

[0101] (3.4) Example of specification change In order to define the above-described operation example 1 (specifically, operation example 1-3), the 3GPP specifications may be defined as follows, for example.

[0102] Figure 7 shows an example of the SgNB Addition Request Acknowledge specification. Specifically, Figure 7 shows an example of the SgNB Addition Request Acknowledge specification specified in 3GPP TS36.423 Chapter 9.1.4.2. As shown in Figure 7, the RRC config indication may specify the RRC configuration of both the SCG config and the radio bearer config (Option 2 described above).

[0103] Figure 8 shows a specified example of SgNB Modification Request Acknowledge. Specifically, Figure 8 shows a specified example of SgNB Modification Request Acknowledge specified in 3GPP TS36.423 Chapter 9.1.4.6. As shown in Figure 8, the RRC config indication may specify that it is the RRC configuration of SCG config (Option 1 described above).

[0104] Fig. 9 shows a specified example of the RRC config indication. Specifically, Fig. 9 shows a specified example of the RRC config indication specified in 3GPP TS36.423 Chapter 9.1.4.132. As shown in Fig. 9, it may be specified that the RRC config indication means both the SCG config and the SCG radio bearer config (option 2).

[0105] It should be noted that the contents shown in FIGS. 7 to 9 are examples of rules, and different expressions may be used as long as they specify similar operations.

[0106] (4) Actions and Effects According to the above-described embodiment, the following advantageous effects can be obtained. Specifically, according to the wireless communication system 10 (eNB100A(MN)), the meaning of the RRC config indication (full config.) can be correctly recognized depending on the type of inter-node message including the RRC config indication, and therefore, appropriate RRC configuration for the SCG (SN) can be realized. Furthermore, this can prevent failures during modification of the SN (gNB) (SgNB modification failure).

[0107] In particular, in this embodiment, the interpretation of the meaning of the RRC config indication (full config.) can be changed depending on the type of inter-node message (SgNB Addition Request Acknowledge, SgNB Modification Required, or SgNB Modification Request Acknowledge), thereby making it possible to achieve more appropriate RRC configuration according to specific operations related to the SgNB.

[0108] In addition, in this embodiment, eNB100A (MN) can perform appropriate operations, such as releasing an SN-terminated bearer, based on the type of inter-node message that includes an RRC config indication (full config.), thereby improving the reliability of dual connectivity such as EN-DC.

[0109] (5) Other embodiments Although the embodiments have been described above, it will be obvious to those skilled in the art that the present invention is not limited to the description of the embodiments and that various modifications and improvements are possible.

[0110] For example, in the above-described embodiment, an EN-DC in which the MN is an eNB and the SN is a gNB has been described as an example, but as described above, other DCs may be used. Specifically, it may be an NR-DC in which the MN is a gNB and the SN is a gNB, or an NE-DC in which the MN is a gNB and the SN is an eNB.

[0111] Also, in the above description, "configure," "activate," "update," "indicate," "enable," "specify," and "select" may be interchangeable. Similarly, "link," "associate," "correspond," and "map" may be interchangeable, and "allocate," "assign," "monitor," and "map" may also be interchangeable.

[0112] Furthermore, specific, dedicated, UE-specific, and UE-dedicated may be interchangeable. Similarly, common, shared, group-common, UE-common, and UE-shared may be interchangeable.

[0113] Furthermore, the block diagrams (FIGS. 2 and 3) used in the description of the above-described embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are connected directly or indirectly (for example, by wire, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0114] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how each is implemented.

[0115] Furthermore, the above-described eNB100A, gNB100B, and UE200 (the devices) may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 10 is a diagram showing an example of the hardware configuration of the devices. As shown in Fig. 10, the devices may be configured as a computer including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0116] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the apparatus may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0117] Each functional block of the device (see Figure 2.3) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0118] In addition, each function of the device is realized by loading specified software (programs) onto hardware such as processor 1001 and memory 1002, causing processor 1001 to perform calculations, control communication via communication device 1004, and control at least one of reading and writing data in memory 1002 and storage 1003.

[0119] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, and the like.

[0120] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-mentioned embodiments. Furthermore, the various processes described above may be executed by one processor 1001, or may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0121] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store a program (program code), a software module, etc., that can execute a method according to an embodiment of the present disclosure.

[0122] Storage 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned recording medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0123] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module.

[0124] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0125] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0126] Furthermore, each device such as the processor 1001 and the memory 1002 is connected to a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0127] Furthermore, the device may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0128] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0129] Each aspect / embodiment described in the present disclosure may be applied to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, a 4th generation mobile communication system (4G), a 5th generation mobile communication system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable system, and a next-generation system extended based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A and 5G) may also be applied.

[0130] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0131] In the present disclosure, a specific operation described as being performed by a base station may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0132] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0133] The input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. The input and output information may be overwritten, updated, or added to. The output information may be deleted. The input information may be sent to another device.

[0134] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0135] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0136] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0137] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0138] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0139] Note that terms explained in this disclosure and terms 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 be called a carrier frequency, a cell, a frequency carrier, etc.

[0140] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0141] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0142] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0143] In this disclosure, terms such as "base station (BS)," "radio 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" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0144] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head: RRH)).

[0145] The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage area.

[0146] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0147] A mobile station may also be referred to by those skilled in the art as a 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 suitable terminology.

[0148] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0149] Furthermore, a base station in the present disclosure may be read as a mobile station (user terminal, the same applies hereinafter). For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a mobile station is replaced with communication between multiple mobile stations (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the mobile station may be configured to have the functions of a base station. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as uplink channel and downlink channel may be read as side channel.

[0150] Similarly, a mobile station in the present disclosure may be interpreted as a base station, in which case the base station may have the functions of a mobile station.

[0151] A radio frame may consist of one or more frames in the time domain.

[0152] Each of the one or more frames in the time domain may be called a subframe, and a subframe may further be made up of one or more slots in the time domain.

[0153] A subframe may be of a fixed time length (eg, 1 ms) that is independent of numerology.

[0154] Numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by a transceiver in the frequency domain, and specific windowing operations performed by a transceiver in the time domain.

[0155] A slot may consist of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) A slot may be a numerology-based time unit.

[0156] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0157] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0158] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0159] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0160] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0161] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0162] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0163] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0164] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain.

[0165] The number of subcarriers included in an RB may be the same regardless of the numerology, and may be, for example, 12. The number of subcarriers included in an RB may also be determined based on the numerology.

[0166] The time domain of an RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each TTI, subframe, etc. may be composed of one or more resource blocks.

[0167] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0168] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0169] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0170] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0171] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0172] The above-described structures of the radio frame, subframe, slot, minislot, and symbol are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

[0173] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0174] The reference signal may also be abbreviated as Reference Signal (RS), and may also be called a pilot depending on the applicable standard.

[0175] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0176] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0177] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed therein or that the first element must precede the second element in some way.

[0178] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0179] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0180] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0181] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." Note that the term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0182] Although the present disclosure has been described in detail above, it is 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 modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]

[0183] 10. Wireless communication systems 20 E-UTRAN 30 NG RAN 100A eNB 100B gNB 110 Radio Communication Department 120 RRC processing unit 130 DC processing section 140 Control Unit 200 UE 210 Radio Communication Department 220 RRC processing unit 230 DC processing section 240 Control Unit 1001 processor 1002 memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output Device 1007 Bus

Claims

1. A method for providing a wireless resource control system, comprising: a receiving unit configured to receive instruction information related to a radio resource control layer configuration from a target secondary node when a terminal changes a secondary node that executes dual connectivity; a control unit that releases a radio bearer and changes a setting related to a secondary cell group when the instruction information is included in a message responding to a request for addition of the secondary node; A radio base station comprising:

2. A receiving unit that receives instruction information related to configuration of a radio resource control layer from a secondary node on which a terminal executes dual connectivity; a control unit that maintains a radio bearer and changes a setting related to a secondary cell group when the instruction information is included in a message responding to a request for changing a secondary node; A radio base station comprising:

3. The radio bearer is terminated at the secondary node.

3. The radio base station according to claim 1 or 2.

4. A radio base station as described in Claim 2, wherein the receiving unit receives the message during an intra-CU inter-DU SCG change.

5. A transmitting unit that transmits instruction information related to setting of a radio resource control layer to a master node on which a terminal executes dual connectivity; a control unit that instructs the release of the radio bearer and the change of the setting related to the secondary cell group by including the instruction information in a message responding to a request for addition of the secondary node; A radio base station comprising:

6. A wireless communication system including a first wireless base station and a second wireless base station, The first radio base station The terminal is a master node that runs dual connectivity, a receiving unit that receives instruction information related to a configuration of a radio resource control layer from the second radio base station; a control unit that releases a radio bearer and changes a setting related to a secondary cell group when the instruction information is included in a message responding to a request for addition of the secondary node; Equipped with The second radio base station a target secondary node when the terminal changes a secondary node that executes the dual connectivity; a transmitter that transmits the instruction information to the first radio base station; a control unit that instructs the release of the radio bearer and the change of the setting by including the instruction information in the message; Equipped with Wireless communication system.

7. A step of receiving instruction information related to configuration of a radio resource control layer from a target secondary node when a terminal changes a secondary node that performs dual connectivity; If the indication information is included in a message responding to a request for addition of the secondary node, releasing a radio bearer and changing a setting related to a secondary cell group; A wireless communication method comprising:

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