Terminal, network device, wireless communication system, and wireless communication method

Abstract

This terminal comprises: a reception unit that receives configuration information for mobility triggered by a lower layer; and a control unit that applies the mobility in accordance with the configuration information for the mobility, wherein the mobility includes first mobility between subordinate cells that, in a case in which nodes that are responsible for the user plane are the same node, can connect to said same node, and second mobility between subordinate cells that, in a case in which the nodes responsible for the user plane are different nodes, can connect to the respective different nodes, and the configuration information for the mobility includes, as configuration information relating to one cell, information that corresponds to each of the first mobility and the second mobility.

Description

Terminal, network device, wireless communication system, and wireless communication method

[0001] The present disclosure relates to a terminal, a network device, a wireless communication system, and a wireless communication method that support LTM (Lower-layer Triggered Mobility).

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

[0003] Here, 3GPP has proposed LTM within a CU (Central Unit) (Intra-CU LTM) and LTM between CUs (Inter-CU LTM) as LTM (Lower-layer Triggered Mobility) (e.g., Non-Patent Document 1). Furthermore, 3GPP has proposed LTM (hereinafter referred to as PDCP anchor keep LTM) that does not require PDCP re-establishment and security key update for LTM between candidate cells by setting cells under the control of DUs that can be connected to the same CU-UP (User Plane) as candidate cells, whether it is Intra-CU LTM or Inter-CU LTM (e.g., Non-Patent Document 2).

[0004] “New WID: NR mobility enhancements Phase 4”, RP-234036, 3GPP TSG RAN Meeting #102, 3GPP, December 2023 “Discussion on inter-gNB LTM”, RP-2402925, 3GPP TSG RAN Meeting #125-bis, 3GPP, April 2024

[0005] Incidentally, 3GPP Release 18 specifies Intra-CU LTM, and 3GPP Release 19 is discussing an extended version of Inter-CU LTM. These LTMs (hereinafter referred to as Basic LTM) may eliminate the need for PDCP re-establishment and security key update for Intra-CU LTM, while requiring PDCP re-establishment and security key update for Inter-CU LTM.

[0006] Against this background, the inventors conducted extensive research and discovered the need to apply LTM appropriately, focusing on cases where PDCP anchor keep LTM and Basic LTM can be applied simultaneously.

[0007] Therefore, the present disclosure has been made to solve the above-mentioned problems, and aims to provide a terminal, a network device, a wireless communication system, and a wireless communication method that enable appropriate application of LTM in cases where PDCP anchor keep LTM and Basic LTM can be applied simultaneously.

[0008] An aspect of the disclosure is a terminal comprising: a receiving unit that receives configuration information for mobility triggered in a lower layer; and a control unit that applies the mobility according to the configuration information for the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0009] An aspect of the disclosure is a network device comprising: a transmitting unit that transmits configuration information for mobility triggered at a lower layer; and a control unit that assumes that a terminal will apply the mobility according to the configuration information for the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the configuration information for the mobility includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0010] An aspect of the disclosure is a wireless communication system comprising a terminal and a network device provided in a network, wherein the network device comprises a transmitting unit that transmits configuration information for mobility triggered at a lower layer, and the terminal comprises a control unit that applies the mobility according to the configuration information for the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0011] An aspect of the disclosure is a wireless communication method comprising the steps of receiving configuration information for mobility triggered at a lower layer and applying the mobility according to the configuration information for the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the configuration information for the mobility includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0012] FIG. 1 is a diagram illustrating an overall schematic configuration of a wireless communication system 10. FIG. 2 is a diagram illustrating a frequency range used in a cellular network. FIG. 3 is a diagram illustrating an example configuration of a radio frame, a subframe, and a slot used in a cellular network. FIG. 4 is a functional block configuration diagram of a UE 200. FIG. 5 is a functional block configuration diagram of a network device 50. FIG. 6 is a diagram illustrating an AI / ML model. FIG. 7 is a diagram illustrating an operation example. FIG. 8 is a diagram illustrating operation example 1. FIG. 9 is a diagram illustrating operation example 1. FIG. 10 is a diagram illustrating operation example 2. FIG. 11 is a diagram illustrating operation example 2. FIG. 12 is a diagram illustrating operation example 3. FIG. 13 is a diagram illustrating operation example 4. FIG. 14 is a diagram illustrating an example of the hardware configuration of a gNB 100 and a UE 200. FIG. 15 is a diagram illustrating an example configuration of a vehicle 2001.

[0013] 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.

[0014] [Embodiment] (1) Overall Schematic Configuration of Wireless Communication System Fig. 1 is an overall schematic configuration diagram of a wireless communication system 10 according to an embodiment. The wireless communication system 10 includes a terminal 200 (hereinafter referred to as UE (User Equipment) 200), a first network 10A, and a second network 10B.

[0015] The first network 10A has a radio access network 20A and a core network 30A. The radio access network 20A includes a base station 100A that performs radio communication with the UE 200. Note that the first network 10A may not have the radio access network 20A but may have the base station 100A. The first network 10A may not have the core network 30A. The base station 100A may be configured by a DU (Distributed Unit) and a CU (Central Unit). The DU may perform processing of layers below the MAC layer. The CU may perform processing above the PDCP layer.

[0016] The first network 10A may be a network conforming to a new technology (6G). 6G may be referred to as Beyond 5G or 5G Evolution. The first network 10A may be a network conforming to an existing technology (5G). 5G may be referred to as 5G New Radio (NR).

[0017] The second network 10B has a radio access network 20B and a core network 30B. The radio access network 20B includes a base station 100B that performs radio communication with the UE 200. Note that the second network 10B may not have the radio access network 20B but may have the base station 100B. The second network 10B may not have the core network 30B. The base station 100B may be configured by a DU and a CU.

[0018] The second network 10B may be a network conforming to existing technology (5G), which may be referred to as 5G New Radio (NR). The second network 10B may be a network conforming to new technology (6G), which may be referred to as Beyond 5G or 5G Evolution.

[0019] Here, the first network 10A and the second network 10B may have different radio access schemes. For example, the radio access scheme may be a cellular network radio access scheme called 5G, Beyond 5G, 5G Evolution, 6G, or the like.

[0020] First, the cellular network may support multiple frequency ranges (FR) as shown in Figure 2. For example, as shown in Figure 2, the cellular network may support FR1 and FR2. The frequency bands of each FR are as follows:

[0021] ・FR1: 410 MHz to 7.125 GHz ・FR2-1: 24.25 GHz to 52.6 GHz ・FR2-2: Over 52.6 GHz to 71 GHz FR1 may use a sub-carrier spacing (SCS) of 15, 30, or 60 kHz and a bandwidth (BW) of 5 to 100 MHz. FR2 is a higher frequency than FR1 and may use an SCS of 60 kHz or 120 kHz (including 240 kHz) and a bandwidth (BW) of 50 to 400 MHz.

[0022] Furthermore, cellular networks may also support higher frequency bands than the FR2 frequency band, specifically, frequency bands above 52.6 GHz up to 71 GHz or 114.25 GHz.

[0023] Second, the cellular network may correspond to the radio frames, subframes and slots shown in FIG.

[0024] As shown in Figure 3, one slot consists of 14 symbols, and the larger (wider) the SCS, the shorter the symbol period (and slot period). In addition to 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz, the SCS may also use 480 kHz, 960 kHz, etc.

[0025] Furthermore, the number of symbols constituting one slot does not necessarily have to be 14 (for example, 28 symbols or 56 symbols). Furthermore, the number of slots per subframe may differ depending on the SCS.

[0026] The time direction (t) shown in Fig. 3 may be called a time domain, a symbol period, a symbol time, etc. The frequency direction may be called a frequency domain, a resource block, a subcarrier, a bandwidth part (BWP), etc.

[0027] (2) Functional Block Configuration of Wireless Communication System The functional block configuration of the wireless communication system 10 will be described below.

[0028] First, the functional block configuration of the UE 200 will be described.

[0029] Fig. 4 is a functional block diagram of UE 200. As shown in Fig. 4, UE 200 includes radio signal transmitting / receiving unit 210, amplifier unit 220, modem unit 230, control signal / reference signal processing unit 240, encoding / decoding unit 250, data transmitting / receiving unit 260, and control unit 270.

[0030] The radio signal transmitting / receiving unit 210 transmits and receives radio signals conforming to 5G or 6G. The radio signal transmitting / receiving unit 210 supports Massive MIMO, CA that uses a bundle of multiple CCs, and DC that simultaneously communicates between a UE and two NG-RAN nodes.

[0031] The amplifier unit 220 is configured by a PA (Power Amplifier) / LNA (Low Noise Amplifier), etc. The amplifier unit 220 amplifies the signal output from the modulation / demodulation unit 230 to a predetermined power level. The amplifier unit 220 also amplifies the RF signal output from the radio signal transmission / reception unit 210.

[0032] The modem unit 230 performs data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (gNB 100 or another gNB). The modem unit 230 may apply Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) / Discrete Fourier Transform - Spread (DFT-S-OFDM). Furthermore, DFT-S-OFDM may be used not only for the uplink (UL) but also for the downlink (DL).

[0033] The control signal and reference signal processor 240 executes processing related to various control signals transmitted and received by the UE 200 and processing related to various reference signals transmitted and received by the UE 200 .

[0034] Specifically, the control signal / reference signal processing unit 240 receives various control signals, for example, control signals of a radio resource control layer (RRC), transmitted via a predetermined control channel from the gNB 100. In addition, the control signal / reference signal processing unit 240 transmits various control signals to the gNB 100 via a predetermined control channel.

[0035] The control signal / reference signal processing unit 240 performs processing using reference signals (RS) such as a Demodulation Reference Signal (DM-RS) and a Phase Tracking Reference Signal (PT-RS).

[0036] DM-RS is a terminal-specific reference signal (pilot signal) known between the base station and the terminal to estimate the fading channel used for data demodulation. PT-RS is a terminal-specific reference signal intended to estimate phase noise, which is an issue in high frequency bands.

[0037] In addition to DM-RS and PT-RS, the reference signals may also include a Channel State Information-Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), and a Positioning Reference Signal (PRS) for location information.

[0038] The channels include control channels and data channels, such as a PDCCH (Physical Downlink Control Channel), a PUCCH (Physical Uplink Control Channel), a RACH (Random Access Channel), a Downlink Control Information (DCI) including a Random Access Radio Network Temporary Identifier (RA-RNTI), and a Physical Broadcast Channel (PBCH).

[0039] Furthermore, the data channel includes a PDSCH (Physical Downlink Shared Channel) and a PUSCH (Physical Uplink Shared Channel). Data refers to data transmitted via the data channel. The data channel may be interpreted as a shared channel.

[0040] Here, the control signal and reference signal processor 240 may receive downlink control information (DCI). The DCI includes existing fields for storing DCI Formats, Carrier indicator (CI), BWP indicator, FDRA (Frequency Domain Resource Assignment), TDRA (Time Domain Resource Assignment), MCS (Modulation and Coding Scheme), HPN (HARQ Process Number), NDI (New Data Indicator), RV (Redundancy Version), and the like.

[0041] The value stored in the DCI Format field is an information element that specifies the format of the DCI. The value stored in the CI field is an information element that specifies the CC to which the DCI applies. The value stored in the BWP indicator field is an information element that specifies the BWP to which the DCI applies. The BWP that can be specified by the BWP indicator is set by an information element (BandwidthPart-Config) included in the RRC message. The value stored in the FDRA field is an information element that specifies the frequency domain resource to which the DCI applies. The frequency domain resource is identified by the value stored in the FDRA field and an information element (RA Type) included in the RRC message. The value stored in the TDRA field is an information element that specifies the time domain resource to which the DCI applies. The time domain resource is identified by the value stored in the TDRA field and information elements (pdsch-TimeDomainAllocationList, pusch-TimeDomainAllocationList) included in the RRC message. The time domain resource may be identified by the value stored in the TDRA field and a default table. The value stored in the MCS field is an information element that specifies the MCS to which the DCI applies. The MCS is identified by the value stored in the MCS and an MCS table. The MCS table may be specified by an RRC message or may be determined by RNTI scrambling. The value stored in the HPN field is an information element that specifies the HARQ process to which the DCI is applied. The value stored in the NDI field is an information element for specifying whether the data to which the DCI is applied is initial transmission data. The value stored in the RV field is an information element that specifies the redundancy of the data to which the DCI is applied.

[0042] The encoding / decoding unit 250 performs data division / concatenation and channel coding / decoding for each predetermined communication destination (gNB100 or another gNB).

[0043] Specifically, the encoding / decoding unit 250 divides the data output from the data transmitting / receiving unit 260 into pieces of a predetermined size, performs channel coding on the divided data, decodes the data output from the modem unit 230, and concatenates the decoded data.

[0044] The data transmitter / receiver 260 transmits and receives Protocol Data Units (PDUs) and Service Data Units (SDUs). Specifically, the data transmitter / receiver 260 assembles and disassembles PDUs / SDUs in multiple layers (such as a Medium Access Control layer (MAC), a Radio Link Control layer (RLC), and a Packet Data Convergence Protocol layer (PDCP)). The data transmitter / receiver 260 also performs data error correction and retransmission control based on Hybrid Automatic Repeat Request (HARQ).

[0045] The control unit 270 controls each functional block constituting the UE 200. In an embodiment, the control unit 270 may be configured to apply mobility (LTM) in accordance with configuration information of mobility (LTM) triggered in a lower layer. The LTM includes a first mobility (hereinafter referred to as PDCP anchor keep LTM) between subordinate cells connectable to the same node when the node responsible for the user plane is the same node, and a second mobility (hereinafter referred to as Basic LTM) between subordinate cells connectable to different nodes when the nodes responsible for the user plane are different nodes.

[0046] In an embodiment, the radio signal transceiver 210 may be configured as a receiver that receives configuration information for low layer triggered mobility (LTM). The mobility configuration information includes information corresponding to each of a first mobility (PDCP anchor keep LTM) and a second mobility (Basic LTM) as configuration information for one cell.

[0047] Second, the functional block configuration of the network device 50 will be described. For example, the network device 50 is provided in the first network 10A or the second network 10B. That is, the network device 50 may be the base station 100A, may be a CU that constitutes part of the base station 100A, or may be a DU that constitutes part of the base station 100A. The network device 50 may be the base station 100B, may be a CU that constitutes part of the base station 100B, or may be a DU that constitutes part of the base station 100B.

[0048] As shown in FIG. 5, the network device 50 includes a receiving unit 51 , a transmitting unit 52 , and a control unit 53 .

[0049] The receiver 51 receives various signals from the UE 200. The receiver 51 may receive a control signal (PUCCH) or a data signal (PUSCH).

[0050] The transmitter 52 transmits various signals to the UE 200. The transmitter 52 may transmit a control signal (PDCCH) or a data signal (PDSCH).

[0051] In an embodiment, the transmitter 52 may comprise a transmitter that transmits configuration information for low layer triggered mobility (LTM).

[0052] The control unit 53 controls each block constituting the network device 50. The control unit 53 may be configured as a control unit that assumes that the UE 200 applies the mobility (LTM) in accordance with the setting information of the mobility (LTM) triggered in a lower layer.

[0053] (3) AI / ML Model The AI / ML model will be described below. The AI / ML model may be used to measure (predict) the above-mentioned slice-related prediction information.

[0054] As shown in FIG. 6, an AI / ML model may include functions such as data collection, model training, model interface, model management / performance monitoring, and model storage.

[0055] Data collection collects model input data used to measure (predict) predictive information. Data collection outputs input data (Training Data) to Model training. Data collection outputs input data (Monitoring Data) to Model Management / Performance monitoring. Data collection outputs input data (Interface Data) to Model Interface.

[0056] Model training performs training, validation, testing, etc. of a model used to measure (predict) predictive information based on training data. Model training may also perform pre-processing such as cleaning, formatting, and conversion of training data. Model training outputs the trained or updated model to model storage.

[0057] The Model Interface uses a model retrieved from the Model storage to output prediction information (Output) corresponding to input data (Interface Data). The Model Interface may also output the prediction information (Output) as feedback to Model Management / Performance monitoring.

[0058] Model Management / Performance Monitoring outputs information (Model Interface Control) to the Model Interface that is used to identify the model used in the Model Interface. Identification may also be referred to as Activate, Deactivate, Select, Switch, Fallback, etc. Model Management / Performance Monitoring outputs information (Model training control) to Model Training that is used to retrain or update the model based on input data (Monitoring Data) and prediction information (Output).

[0059] The Model storage stores the model output from Model training. The Model storage outputs the stored model to the Model Interface. The output of the model may also be referred to as Model deliver / transfer.

[0060] (4) Issues 3GPP Release 18 specifies Intra-CU LTM, and 3GPP Release 19 is discussing an extended version of Inter-CU LTM. These LTMs (Basic LTM) may eliminate the need for PDCP re-establishment and security key update for Intra-CU LTM, while requiring PDCP re-establishment and security key update for Inter-CU LTM.

[0061] Against this background, the inventors conducted extensive research and discovered the need to apply LTM appropriately, focusing on cases where PDCP anchor keep LTM and Basic LTM can be applied simultaneously.

[0062] Specifically, in terms of the LTM RTT (Round Trip Time), the order of preference is Basic LTM (Intra-CU) <= PDCP anchor keep LTM (Intra-CU / Inter-CU) <= Basic LTM (Inter-CU). However, it is not possible to distinguish whether a cell is a candidate cell for PDCP anchor keep LTM or Basic LTM, and it is not possible to select an appropriate candidate cell in terms of the LTM RTT.

[0063] (5) Operation Example In order to solve the above-described problem, the following operation may be performed. Specifically, the UE 200 applies the LTM according to the LTM configuration information. The LTM configuration information includes information corresponding to each of the PDCP anchor keep LTM and the Basic LTM as configuration information related to one cell. The application of the LTM may include the selection of a candidate cell.

[0064] Here, the configuration information of the existing LTM may include information (ltm-NoResetID) allocated to distinguish whether an RLC reset is required and information (ltm-NoResetID-2) allocated to distinguish whether a PDCP reset is required. In the operation example, a case will be described in which the LTM configuration information includes ltm-NoResetID and ltm-NoResetID-2 in a manner that allows distinguishing between the PDCP anchor keep LTM and the Basic LTM.

[0065] For example, as shown in Figure 7, in a case where DU#1 and DU#2 exist under CU #1 and DU#3 and DU#4 exist under CU#2, it is assumed that DU#1, DU#2, and DU#3 exist under CU-UP#1.

[0066] First, in the case where the UE is located in Cell#1, in the LTM between Cell#1 and Cell#2, since Cell#1 and Cell#2 are under the control of the same DU#1 and CU#1, the ltm-NoResetID and ltm-NoResetID-2 are the same.

[0067] Secondly, in the case where the UE is located in Cell#2, in the LTM between Cell#2 and Cell#3, the ltm-NoResetID is different because Cell#2 and Cell#3 are under different DUs (DU#1 and DU#2), but the ltm-NoResetID-2 is the same because DU#1 and DU#2 are under the same CU#1.

[0068] Third, in the case where a UE is present in Cell#3, in the LTM between Cell#3 and Cell#4, Cell#3 and Cell#4 are under the control of different DUs (DU#2 and DU#3), so ltm-NoResetID is different. Here, from the viewpoint of PDCP anchor keep LTM, DU#2 and DU#3 are under the control of the same CU-UP#1, so ltm-NoResetID-2 is the same. On the other hand, from the viewpoint of Basic LTM, DU#2 and DU#3 are under the control of different CUs (CU#1 and CU#2), so ltm-NoResetID-2 is different.

[0069] In the operation example, a method for setting information for PDCP anchor keep LTM (e.g., ltm-NoResetID=3, ltm-NoResetID-2=1) and candidate information for Basic LTM (e.g., ltm-NoResetID=3, ltm-NoResetID-2=2) for Cell#4 having the same PCI (Physical Cell ID) will be described.

[0070] (5-1) Operation Example 1 In operation example 1, candidate information for PDCP anchor keep LTM and candidate information for Basic LTM are defined separately as configuration information for one cell.

[0071] For example, as shown in Fig. 8, the LTM configuration information (LTM-Config-r18) may include information (ltm-ServingCellNoResetID-2-r19) indicating whether a PDCP reset is required. Furthermore, the LTM configuration information may include a candidate cell addition list (ltm-CandidateToAddModList-r18), etc. The ltm-CandidateToAddModList-r18 may include candidate cell information (LTM-Candidate-r18).

[0072] For example, as shown in Fig. 9, each piece of candidate cell information (LTM-Candidate-r18) may be associated with a candidate ID (ltm-CandidateId-r18) and a physical cell ID (ltm-CandidatePCI-r18), and may include information (ltm-NoResetID-2-r19) assigned to determine whether a PDCP reset is required, information indicating whether a PDCP reset is not required (ltm-WithoutPDCPReset-r19), etc. Each piece of candidate cell information (LTM-Candidate-r18) may be associated with a candidate ID (ltm-CandidateId-r18) and a physical cell ID (ltm-CandidatePCI-r18), and may include a candidate cell configuration (ltm-CandidateConfig-r18) and information (ltm-NoResetID-r18) assigned to determine whether an RLC reset is required.

[0073] In operation example 1, candidate information for PDCP anchor keep LTM and candidate information for Basic LTM are separately included as candidate cell information (LTM-Candidate-r18) having the same physical cell ID (ltm-CandidatePCI-r18). The candidate information for PDCP anchor keep LTM and the candidate information for Basic LTM are managed by different candidate IDs (ltm-CandidateId-r18).

[0074] As described above, in operation example 1, candidate information for PDCP anchor keep LTM and candidate information for Basic LTM are defined separately as configuration information for one cell having the same PCI. With this configuration, it is possible to separately configure information for PDCP anchor keep LTM (e.g., ltm-NoResetID-r18, ltm-NoResetID-2-r19) and candidate information for Basic LTM (e.g., ltm-NoResetID-r18, ltm-NoResetID-2-r19) for one cell having the same PCI (Physical Cell ID).

[0075] (5-2) Operation Example 2 In Operation Example 2, the configuration information for one cell includes candidate information for LTM, in which information on PDCP anchor keep LTM and information on Basic LTM are defined separately. For example, as shown in FIG. 10 , the LTM configuration information (LTM-Config-r18) may include information (ltm-ServingCellNoResetID-2-r19) indicating whether a PDCP reset is required. Furthermore, the LTM configuration information may include an addition list of candidate cells (ltm-CandidateToAddModList-r18), etc. The ltm-CandidateToAddModList-r18 may include candidate cell information (LTM-Candidate-r18).

[0076] For example, as shown in FIG. 11 , the candidate cell information (LTM-Candidate-r18) may include information (ltm-NoResetID-2-r19) allocated for Basic LTM to distinguish whether a PDCP reset is required, in addition to information (ltm-NoResetID-2-r19) allocated for PDCP anchor keep LTM to distinguish whether a PDCP reset is required, in association with the candidate ID (ltm-CandidateId-r18) and the physical cell ID (ltm-CandidatePCI-r18). The candidate cell information (LTM-Candidate-r18) may include, in association with the candidate ID (ltm-CandidateId-r18) and the physical cell ID (ltm-CandidatePCI-r18), a candidate cell configuration for Basic LTM (ltm-CandidateConfig-r18) and information allocated for Basic LTM to distinguish whether or not an RLC reset is required (ltm-NoResetID-r18), as well as a candidate cell configuration for PDCP anchor keep LTM (ltm-CandidateConfig--forNoResetPDCP-r19) and information allocated for PDCP anchor keep LTM to distinguish whether or not an RLC reset is required (ltm-NoResetID-forNoResetPDCP-r19).

[0077] In operation example 2, candidate cell information (LTM-Candidate-r18) having the same physical cell ID (ltm-CandidatePCI-r18) separately includes information related to PDCP anchor keep LTM and information related to Basic LTM. The information related to PDCP anchor keep LTM and information related to Basic LTM are managed by the same candidate ID (ltm-CandidateId-r18).

[0078] As described above, in operation example 2, the configuration information for one cell having the same PCI separately includes information on PDCP anchor keep LTM and information on Basic LTM. With this configuration, for one cell having the same PCI (Physical Cell ID), it is possible to separately configure information for PDCP anchor keep LTM (e.g., ltm-NoResetID-forNoResetPDCP-r19, ltm-NoResetID-2-forNoResetPDCP-r19) and candidate information for Basic LTM (e.g., ltm-NoResetID-r18, ltm-NoResetID-2-r19).

[0079] (5-3) Operation Example 3 In Operation Example 3, a description will be given of an LTM switch command (MAC CE) transmitted from the gNB 100 to the UE 200. Operation Example 3 may be an operation example based on Operation Example 1 or Operation Example 2.

[0080] The LTM switch command (MAC CE) may have the configuration shown in Fig. 12. In such a configuration, the LTM switch command (MAC CE) may have a "P" field (e.g., at the beginning of Oct1). The "P" field is a field that specifies whether or not PDCP re-establishment (i.e., PDCP reset) is involved in switching to the target cell. In other words, the "P" field may be a bit that specifies either PDCP anchor keep LTM or Basic LTM when PDCP anchor keep LTM or Basic LTM is selectable for one cell.

[0081] For example, when UE 200 receives an LTM switch command (MAC CE) with the "P" bit set to "1", UE 200 may execute LTM without re-establishing PDCP. That is, when UE 200 receives an LTM switch command (MAC CE) with the "P" bit set to "1", UE 200 may execute PDCP anchor keep LTM.

[0082] For example, when UE 200 receives an LTM switch command (MAC CE) in which the "P" bit is not set to "1", UE 200 may perform PDCP re-establishment and execute LTM. That is, when UE 200 receives an LTM switch command (MAC CE) in which the "P" bit is not set to "1", UE 200 may execute Basic LTM.

[0083] (5-4) Operation Example 4 In Operation Example 4, the operation of the UE 200 in Operation Example 1 will be described.

[0084] First, the operation relating to reception of LTM setting information will be described.

[0085] When UE200 receives two LTM configuration information (LTM-Config shown in FIG. 8), it stores (maintains) two ltm-ServingCellNoResetID-2 variables (VarLTM-ServingCellNoResetID-2) in association with each LTM-Config.

[0086] UE200 receives LTM configuration information (LTM-Config shown in FIG. 8 ), and may perform the following operations if LTM-Config includes ltm-ServingCellNoResetID-2: UE200 may replace the value of ltm-ServingCellNoResetID-2 in VarLTM-ServingCellNoResetID-2 with the received ltm-ServingCellNoResetID-2 if the current VarLTM-ServingCellNoResetID-2 includes ltm-ServingCellNoResetID-2; UE200 stores the received ltm-ServingCellNoResetID-2 in VarLTM-ServingCellNoResetID-2 if the current VarLTM-ServingCellNoResetID-2 does not include ltm-ServingCellNoResetID-2.

[0087] Secondly, an operation related to reception of an LTM switch command (MAC CE), in other words, an operation related to execution of LTM, will be described. The UE 200 may perform the operation shown in FIG.

[0088] If the LTM candidate information does not include ltm-NoResetID-2 and the UE does not have a value stored for ltm-ServingCellNoResetID-2 in VarLTM-ServingCellNoResetID-2, or if the ltm-NoResetID-2 included in the LTM candidate information is different from the value stored for ltm-ServingCellNoResetID-2 in VarLTM-ServingCellNoResetID-2, UE200 may replace the value of ltm-ServingCellNoResetID-2 in VarLTM-ServingCellNoResetID-2 with the ltm-NoResetID-2 included in the LTM candidate information after performing the corresponding PDCP re-establishment.

[0089] (6) Actions and Effects In the embodiment, the UE 200 applies the LTM according to LTM configuration information. The LTM configuration information includes information corresponding to each of the PDCP anchor keep LTM and the Basic LTM as configuration information for one cell. With this configuration, for one cell having the same PCI (Physical Cell ID), it is possible to separately configure information for the PDCP anchor keep LTM (e.g., ltm-NoResetID-forNoResetPDCP-r19, ltm-NoResetID-2-forNoResetPDCP-r19) and candidate information for the Basic LTM (e.g., ltm-NoResetID-r18, ltm-NoResetID-2-r19).

[0090] In an embodiment, the UE 200 receives an LTM switch command (MAC CE) including a field specifying whether or not switching to the target cell involves re-establishing PDCP (i.e., resetting PDCP). With this configuration, even when both PDCP anchor keep LTM and Basic LTM are possible, the UE 200 can appropriately perform LTM.

[0091] (7) Other Embodiments The present invention has been described above in accordance with the embodiments, but it will be obvious to those skilled in the art that the present invention is not limited to these descriptions and that various modifications and improvements are possible.

[0092] The block diagrams (FIGS. 4 and 5) used to explain the above-described embodiments show functional blocks. These functional blocks (components) are realized by any combination of hardware and / or software. Furthermore, the method for 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 directly or indirectly connected (e.g., wired, wireless, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or multiple devices.

[0093] 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, regard, 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.

[0094] Furthermore, the above-described network device 50 and UE 200 (the device) may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 14 is a diagram showing an example of the hardware configuration of the device. As shown in Fig. 14, the device 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.

[0095] 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.

[0096] Each functional block of the device (see FIGS. 4 and 5) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0097] 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.

[0098] 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, and registers.

[0099] 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-described embodiments. Furthermore, the various processes described above may be executed by a single 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.

[0100] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, 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 may store a program (program code), a software module, etc., capable of executing a method according to an embodiment of the present disclosure.

[0101] 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 suitable medium including at least one of memory 1002 and storage 1003.

[0102] 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.

[0103] 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).

[0104] The input device 1005 is an input device (e.g., 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 (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0105] Furthermore, each device such as the processor 1001 and the memory 1002 is connected by 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.

[0106] 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.

[0107] 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.

[0108] 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 enhanced 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.

[0109] 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.

[0110] In the present disclosure, a specific operation described as being performed by a base station may 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.

[0111] 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.

[0112] The input and output information may be stored in a specific location (for example, a memory) or may be managed using a management table. The input and output information may be overwritten, updated, or added. The output information may be deleted. The input information may be transmitted to another device.

[0113] 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).

[0114] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0115] 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.

[0116] 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.

[0117] 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.

[0118] Note that terms described 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.

[0119] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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)).

[0124] 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.

[0125] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0126] 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.

[0127] At least one of the base station and the mobile station may be referred to as 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, the mobile object itself, etc. 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.

[0128] 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 terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0129] 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.

[0130] A radio frame may be made up of one or more frames in the time domain, each of which may be called a subframe.

[0131] A subframe may further be composed of one or more slots in the time domain, and may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0132] Numerology may be communication parameters that apply to the transmission and / or 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 the transceiver in the frequency domain, and specific windowing operations performed by the transceiver in the time domain.

[0133] A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) A slot may be a time unit based on numerology.

[0134] A slot may include multiple minislots. Each minislot may consist of one or multiple 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.

[0135] 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.

[0136] For example, one subframe may be referred to as a transmission time interval (TTI), multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as 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 referred to as a slot, minislot, etc. instead of a subframe.

[0137] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station schedules each user terminal to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) in TTI units. Note that the definition of TTI is not limited to this.

[0138] 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.

[0139] In addition, 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. Furthermore, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0140] 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.

[0141] 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.

[0142] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0143] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0144] 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, etc.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] 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."

[0149] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. 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, etc. may be variously changed.

[0150] 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.

[0151] The reference signal may also be abbreviated as Reference Signal (RS) and may be called a pilot depending on the applicable standard.

[0152] 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."

[0153] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0154] 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.

[0155] 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, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0156] 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.

[0157] 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.

[0158] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." 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."

[0159] 15 shows an example of the configuration of a vehicle 2001. As shown in Fig. 15, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, left and right front wheels 2007, left and right 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.

[0160] The drive unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor.

[0161] The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0162] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2027 provided in the vehicle. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0163] The signals from the various sensors 2021 to 2028 include a current signal from a current sensor 2021 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 2022, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0164] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing various types of information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 2012 uses information obtained from external devices via the communication module 2013, etc., to provide various types of multimedia information and multimedia services to the occupants of the vehicle 1.

[0165] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize driving assistance functions or autonomous driving functions.

[0166] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 1 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from a driving unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, an axle 2009, a microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 2028, which are provided in the vehicle 2001.

[0167] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0168] The communication module 2013 transmits, via wireless communication to an external device, a current signal from the current sensor that is input to the electronic control unit 2010. The communication module 2013 also transmits, via wireless communication to an external device, the rotation speed signals of the front and rear wheels acquired by a rotation speed sensor 2022, the air pressure signals of the front and rear wheels acquired by an air pressure sensor 2023, the vehicle speed signal acquired by a vehicle speed sensor 2024, the acceleration signal acquired by an acceleration sensor 2025, the accelerator pedal depression amount signal acquired by an accelerator pedal sensor 2029, the brake pedal depression amount signal acquired by a brake pedal sensor 2026, the shift lever operation signal acquired by a shift lever sensor 2027, and the detection signals for detecting obstacles, vehicles, pedestrians, etc. acquired by an object detection sensor 2028, all of which are input to the electronic control unit 2010.

[0169] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle. The communication module 2013 also stores the various information received from the external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, axle 2009, sensors 2021 to 2028, and the like provided in the vehicle 2001.

[0170] 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.

[0171] (Additional Note) The above disclosure may be expressed as follows.

[0172] A first feature is a terminal comprising: a receiving unit that receives configuration information of mobility triggered in a lower layer; and a control unit that applies the mobility according to the configuration information of the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0173] A second feature is the terminal according to the first feature, wherein candidate information regarding the first mobility and candidate information regarding the second mobility are defined separately as the configuration information regarding the one cell.

[0174] A third feature is, in the terminal of the first feature, wherein the configuration information regarding the one cell includes candidate information regarding the mobility in which information regarding the first mobility and information regarding the second mobility are defined separately.

[0175] A fourth feature is a network device comprising: a transmitter that transmits configuration information of mobility triggered in a lower layer; and a controller that assumes that a terminal applies the mobility according to the configuration information of the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for a user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the configuration information of the mobility includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0176] A fifth feature is a wireless communication system including a terminal and a network device provided in a network, wherein the network device includes a transmitting unit that transmits configuration information of mobility triggered at a lower layer, and the terminal includes a control unit that applies the mobility according to the configuration information of the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the configuration information of the mobility includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

[0177] A sixth feature is a wireless communication method comprising: receiving configuration information of mobility triggered at a lower layer; and applying the mobility according to the configuration information of the mobility, wherein the mobility includes a first mobility between subordinate cells connectable to the same node in a case where the node responsible for a user plane is the same node, and a second mobility between subordinate cells connectable to each of the different nodes in a case where the nodes responsible for the user plane are different nodes, and the configuration information of the mobility includes, as configuration information for one cell, information corresponding to each of the first mobility and the second mobility.

[0178] 10 Wireless communication system 10A First network 10B Second network 20A, 20B Wireless access network 30A, 30B Core network 50 Network device 51 Receiving unit 52 Transmitting unit 53 Control unit 100A, 100B Base station 200 UE 210 Wireless signal transmitting / receiving unit 220 Amplifying unit 230 Modulation / demodulation unit 240 Control signal / reference signal processing unit 250 Encoding / decoding unit 260 Data transmitting / receiving unit 270 Control unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device 1007 Bus 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Left and right front wheels 2008 Left and right rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 RPM sensor 2023 Air pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port

Claims

1. A terminal comprising: a receiving unit that receives configuration information for mobility triggered in a lower layer; and a control unit that applies the mobility according to the configuration information for the mobility, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

2. The terminal according to claim 1, wherein candidate information regarding the first mobility and candidate information regarding the second mobility are defined separately as the configuration information regarding the one cell.

3. The terminal according to claim 1, wherein the configuration information regarding the one cell includes candidate information regarding the mobility in which information regarding the first mobility and information regarding the second mobility are defined separately.

4. A network device comprising: a transmitting unit that transmits configuration information for mobility triggered in a lower layer; and a control unit that assumes that a terminal will apply the mobility according to the mobility configuration information, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

5. A wireless communication system comprising: a terminal; and a network device provided in a network, wherein the network device comprises a transmitting unit that transmits configuration information for mobility triggered at a lower layer; the terminal comprises a control unit that applies the mobility according to the configuration information for the mobility; the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes; and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

6. A wireless communication method comprising: a step of receiving configuration information for mobility triggered in a lower layer; and a step of applying the mobility according to the mobility configuration information, wherein the mobility includes a first mobility between subordinate cells that can be connected to the same node when the node responsible for the user plane is the same node, and a second mobility between subordinate cells that can be connected to each of the different nodes when the nodes responsible for the user plane are different nodes, and the mobility configuration information includes information corresponding to each of the first mobility and the second mobility as configuration information for one cell.

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