Terminal

Abstract

This terminal performs cell selection according to mobility control or a secondary cell addition-modification procedure triggered by a lower layer, and transmits information related to the cell selection to a network. If the cell selection fails, then the terminal transmits information to the network indicating that the mobility control or the addition-modification procedure has failed.

Description

Terminal

[0001] The present disclosure relates to a terminal that supports L1 / L2 mobility (LTM) and CPAC.

[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)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.

[0003] For example, 3GPP Release 18 is discussing extensions to Layer 1 / Layer 2 mobility (L1 / L2 mobility). L1 / L2 mobility, also known as Lower Layer Triggered Mobility (LTM), is a technology related to the mobility of user equipment (UE) in Layer 1 or Layer 2, including handover (HO) of the UE to another cell. HO using LTM is realized by lower layers such as the Medium Access Control (MAC) layer.

[0004] In addition, in 3GPP Release 19, extensions of SON (Self-Organizing Networks) related to LTM and CPAC (conditional PSCell addition / change) are being considered (Non-Patent Document 1).

[0005] "New WID: Data collection for SON (Self-Organising Networks) / MDT (Minimization of Drive Tests) in NR standalone and MR-DC (Multi-Radio Dual Connectivity) Phase 4", RP-234038, 3GPP TSG RAN Meeting #102, 3GPP, December 2023

[0006] To realize the SON extensions for LTM and CPAC, it is considered important for the UE to report detailed information about the execution of LTM and CPAC to the network. However, the current 3GPP specifications do not allow the UE to report such detailed information to the network.

[0007] Therefore, the following disclosure has been made in consideration of this situation, and aims to provide a terminal that can report information necessary for extending SON regarding LTM and CPAC.

[0008] One aspect of the present disclosure is a terminal (UE) that includes a control unit (control unit 240) that performs cell selection in accordance with mobility control by a lower layer or a procedure for adding or changing a secondary cell, and a transmission unit (RLF / HO reporting unit 220) that transmits information related to the cell selection to a network, and the transmission unit transmits information indicating that the mobility control or the procedure for adding or changing a secondary cell has failed to the network if the cell selection fails.

[0009] One aspect of the present disclosure is a terminal (UE) that includes a control unit (control unit 240) that performs cell selection in accordance with a procedure for adding or changing a secondary cell, and a transmission unit (RLF / HO reporting unit 220) that transmits information related to the cell selection to a network, and the transmission unit transmits to the network the time from receiving a setting instruction to perform the addition or change procedure without initializing information related to the secondary cell to failure of the addition or change of the secondary cell in accordance with the addition or change procedure.

[0010] One aspect of the present disclosure is a terminal (UE) that includes a control unit (control unit 240) that performs cell selection in accordance with mobility control by a lower layer or a procedure for adding or changing a secondary cell, and a transmission unit (RLF / HO reporting unit 220) that transmits information related to the cell selection to a network, wherein, if the selected cell is a candidate target cell to be a transition destination, the control unit applies a configuration of the candidate target cell without transmitting a radio resource control layer message to the network, and the transmission unit transmits identification information of the candidate target cell to the network.

[0011] FIG. 1 is a diagram showing an overall schematic configuration of a wireless communication system 10. FIG. 2 is a diagram showing an example of control using L1 / L2 mobility. FIG. 3 is a functional block diagram of a gNB 100. FIG. 4 is a functional block diagram of a UE 200. FIG. 5 is a diagram showing an example of a sequence of an RLF report / handover failure report. FIG. 6 is a diagram showing an example of the elapsed time from when a UE receives a subsequent CPAC configuration from the network until a PSCell change or PSCell addition fails. FIG. 7 is a diagram showing an example of the elapsed time from the completion of the previous LTM execution until an LTM failure. FIG. 8 is a diagram showing an example of the elapsed time from when a previous CPAC execution is completed until a PSCell change or PSCell addition fails. FIG. 9 is a diagram showing an example of the elapsed time from when a subsequent LTM configuration is received from the network until an LTM failure. FIG. 10 is a diagram showing an example of the hardware configuration of a gNB 100 and a UE 200. FIG. 11 is a diagram showing an example of the configuration of a vehicle 2001.

[0012] 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.

[0013] (1) Overall Schematic Configuration of Wireless Communication System Fig. 1 is a diagram showing the overall schematic configuration of a wireless communication system 10 according to this embodiment. The wireless communication system 10 is a wireless communication system conforming to 5G New Radio (NR) and includes a Next Generation-Radio Access Network 20 (hereinafter, NG-RAN 20) and a terminal 200 (User Equipment 200, hereinafter, UE 200).

[0014] The wireless communication system 10 may be a wireless communication system conforming to a method called Beyond 5G, 5G Evolution, or 6G, or may include a wireless communication system conforming to a method called Long Term Evolution (LTE) or 4G. The wireless communication system 10 may support functions related to the Industrial Internet of Things (IIoT) and Ultra-Reliable and Low Latency Communications (URLLC).

[0015] The NG-RAN 20 includes a radio base station 100 (hereinafter, gNB 100). Note that the specific configuration of the radio communication system 10, including the number of gNBs (or eNBs, etc.) and UEs, is not limited to the example shown in FIG. 1 .

[0016] The gNB 100 may also employ a fronthaul (FH) interface defined by the Open Radio Access Network Alliance (O-RAN). The gNB 100 may include an O-RAN Distributed Unit (O-DU) and an O-RAN Radio Unit (O-RU). The gNB 100 can function as a type of NG-RAN node.

[0017] The NG-RAN 20 actually includes multiple NG-RAN nodes, specifically, gNBs (or ng-eNBs), and is connected to a 5G core network (5GC, not shown). The NG-RAN 20 and the 5GC may be simply referred to as a "network." The 5GC may introduce the concept of CUPS (Control and User Plane Separation), which clearly separates the functions of the user plane and the control plane.

[0018] The gNB100 is a radio base station conforming to NR, and performs radio communication conforming to NR with the UE200. The gNB100 may be configured to include a CU (Central Unit) and a DU (Distributed Unit), and the DU may be separated from the CU and installed in a different geographical location. One or more DUs may be connected to the CU. The gNB100 (gNB-CU) may be connected to each other via an Xn interface, and the CU and DU may be connected to each other via an F1 interface (such as an F1-AP). In this embodiment, the CU may be called a communication device or a central device. The DU may be called a distributed device.

[0019] The gNB100 and UE200 are capable of supporting Massive MIMO, which generates more directional beams by controlling radio signals transmitted from multiple antenna elements; Carrier Aggregation (CA), which aggregates and uses multiple component carriers (CCs); and Dual Connectivity (DC), which enables simultaneous communication between the UE and multiple NG-RAN nodes.

[0020] The type of DC may be Multi-RAT Dual Connectivity (MR-DC) that uses multiple radio access technologies, or NR-NR Dual Connectivity (NR-DC) that uses only NR. For example, one gNB may constitute a master node (MN), and one or more other gNBs may constitute secondary nodes (SNs).

[0021] In the wireless communication system 10, not only mobility control of the UE 200 in layer 3 (which may be called L3 Mobility) but also mobility control in layer 1 and / or layer 2 (L1 / L2 Mobility) may be applied. L1 / L2 Mobility may be called LTM, and the name LTM will be mainly used hereinafter.

[0022] L3 Mobility may be interpreted as mobility control at the Radio Resource Control layer (RRC), while L1 / L2 Mobility may be interpreted as mobility control at the Physical layer (PHY), Medium Access Control layer (MAC), Radio Link Control layer (RLC), and Packet Data Convergence Protocol layer (PDCP) (mobility control by lower layers).

[0023] LTM may also be supported between the CU and DU of a radio base station (gNB), and LTM may include subsequent LTM, which allows cell switching to be performed continuously without initializing information about candidate cells.

[0024] Furthermore, the LTM may include LTM fast failure recovery. LTM fast failure recovery is a mechanism in which, in the event of an LTM failure, the UE 200 performs cell selection, and if the selected cell is an LTM candidate cell (candidate target cell), the UE 200 directly applies the configuration of the candidate cell without transmitting an RRC Reestablishment Request to the gNB 100.

[0025] Furthermore, the wireless communication system 10 may support conditional addition or change (CPAC) 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 one of a plurality of SCells.

[0026] The secondary cell may be referred to 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.

[0027] The conditional PSCell addition / change may be interpreted as a simplified procedure for adding or changing a conditional secondary cell (secondary node). Also, the conditional PSCell addition / change may mean at least one of adding or changing a SCell.

[0028] Also, in CPAC, similar to Subsequent LTM, Subsequent CPAC, which can perform cell switching continuously without initializing information about candidate secondary cells, may be supported. Note that Subsequent LTM may be applied in DC and non-DC, but Subsequent CPAC may be applied only in DC. Furthermore, in CPAC, similar to LTM fast failure recovery, in the event of a CPAC failure, if UE200 performs cell selection and the selected cell is a CPAC candidate cell (candidate target cell), CPAC fast failure recovery may be supported, which directly applies the configuration of the candidate cell without transmitting an RRC Reestablishment Request to gNB100.

[0029] In a broad sense, the mobility of UE200 may mean the ease of movement and maneuverability of UE200, but in this embodiment, it may also mean minimizing call drops, radio link (including beam) failures, unnecessary handovers, ping-pong states, etc.

[0030] Figure 2 shows an example of control by L1 / L2 mobility. As shown in Figure 2, MAC included in the lower layer (Layer 1 / Layer 2), rather than RRC included in Layer 3, can perform measurement reporting, handover (HO) decision from a source cell to a target cell (which may include candidates), and timer management for determining whether HO is successful.

[0031] The MAC may report information related to the measurement report, the HO decision, etc. to a higher layer (RRC). The RRC may manage the state of radio resources accompanying the cell transition of the UE 200 based on the report.

[0032] In this embodiment, the channels include a control channel and a data channel, such as a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), a physical random access channel (PRACH), and a physical broadcast channel (PBCH).

[0033] The data channels include a physical downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH).

[0034] The reference signal includes a Demodulation Reference Signal (DMRS), a Sounding Reference Signal (SRS), a Phase Tracking Reference Signal (PTRS), and a Channel State Information-Reference Signal (CSI-RS), and the signal includes a channel and a reference signal. Furthermore, the data may refer to data transmitted via a data channel.

[0035] (2) Functional Block Configuration of Wireless Communication System Next, the functional block configuration of the wireless communication system 10 will be described. Specifically, the functional block configurations of the gNB 100 and the UE 200 will be described. Fig. 3 is a functional block configuration diagram of the gNB 100. Fig. 4 is a functional block configuration diagram of the UE 200.

[0036] (2.1) gNB100 As shown in FIG. 3, the gNB100 includes a radio communication unit 110, a handover processing unit 120, a measurement setting unit 130, and a control unit 140.

[0037] The wireless communication unit 110 transmits downlink signals (DL signals) conforming to NR, and also receives uplink signals (UL signals) conforming to NR.

[0038] The handover processing unit 120 executes handover of the UE 200. Specifically, the handover processing unit 120 executes handover from a serving cell (source cell) of the UE 200 to another nearby cell (target cell). In particular, in this embodiment, the handover processing unit 120 may execute handover in accordance with L1 / L2 mobility (LTM). Also, in this embodiment, conditional PSCell addition / change (CPAC) may be included as a type of handover.

[0039] The serving cell may be simply interpreted as a cell to which the UE 200 is connected, but more precisely, in the case of an RRC_CONNECTED UE in which carrier aggregation (CA) is not configured, there is only one serving cell that constitutes the primary cell. In the case of an RRC_CONNECTED UE configured using CA, the serving cell may be interpreted as indicating a set of one or more cells including the primary cell and all secondary cells.

[0040] The handover processing unit 120 may receive reports from the UE 200 regarding the handover (which may include LTM and CPAC), such as detailed information regarding the failure or success of the handover.

[0041] The measurement configuration unit 130 performs configuration (measurement configuration) of quality measurements of the serving cell and neighboring cells by the UE 200. Specifically, the measurement configuration unit 130 may perform measurement configuration in layer 3, or may perform measurement configuration in layer 1 and / or layer 2.

[0042] The measurement configuration unit 130 can notify the UE 200 of the contents of the measurement configuration. The UE 200 can measure the quality (e.g., Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ), and Signal-to-Interference plus Noise power Ratio (SINR)) of the serving cell and / or neighboring cell based on the notified measurement configuration. The measurement configuration unit 130 can receive a measurement report from the UE 200 indicating the measurement result of the cell quality.

[0043] The control unit 140 controls each functional block constituting the gNB 100. In particular, in this embodiment, the control unit 140 can perform mobility control with the terminal. Specifically, the control unit 140 can perform not only mobility control according to L3 Mobility but also mobility control according to L1 / L2 Mobility (LTM).

[0044] Furthermore, the control unit 140 can perform addition or change of a secondary cell (SCell) according to conditional PSCell addition / change (CPAC).

[0045] In addition, the control unit 140 can perform control as a CU (source side or target side) or a DU (source side or target side) in a gNB100 having a CU-DU configuration.

[0046] In addition, the control unit 140 may provide a SON function that autonomously performs settings for the UE 200 and settings for the associated network based on a report regarding handover (which may include LTM and CPAC) received by the handover processing unit 120 from the UE 200.

[0047] (2.2) UE 200 As shown in FIG. 4, the UE 200 includes a radio communication unit 210, an RLF / HO reporting unit 220, a handover execution unit 230, and a control unit 240.

[0048] The wireless communication unit 210 transmits an uplink signal (UL signal) conforming to NR. The wireless communication unit 210 also receives an uplink signal (DL signal) conforming to NR.

[0049] The RLF / HO reporting unit 220 performs processing related to radio link failure (RLF) and handover (HO) reporting. Specifically, the RLF / HO reporting unit 220 can transmit an RLF report to the network. The RLF / HO reporting unit 220 can also transmit a handover failure report and a successful handover report to the network.

[0050] The RLF report may be interpreted as a report of a failure related to a radio link established by the UE 200. The handover failure report may be interpreted as a report of a situation when handover to the target cell fails. The successful handover report may be interpreted as a report of a situation when handover to the target cell is successful.

[0051] In this way, the RLF / HO reporting unit 220 can send a report about the handover to the network.

[0052] The RLF / HO reporting unit 220 may send a radio link failure report (RLF report), a handover failure report or a successful handover report to the network, which report includes at least one of the status, quality and result of the handover according to the LTM.

[0053] The RLF / HO reporting unit 220 can measure the quality of the serving cell of the UE 200 and neighboring cells of the serving cell and report the measurement results (Measurement Report) to the network. The RLF / HO reporting unit 220 can perform measurement reporting of the source cell (transfer source cell) and the target cell (transfer destination cell) during handover.

[0054] The quality to be measured may be, for example, the quality (for example, RSRP, RSRQ) included in the Measurement Report specified in 3GPP TS38.331.

[0055] In addition, the RLF / HO reporting unit 220 may transmit information regarding cell selection to the network. In this embodiment, the RLF / HO reporting unit 220 may constitute a transmitting unit.

[0056] Cell selection may refer to cell selection or cell reselection by UE 200. Cell selection may include handover, or cell selection may be interpreted as cell transition. Cell selection may be interpreted as an operation of selecting a cell from multiple candidate cells. The selected cell may be referred to as a candidate target cell. Cell selection may include not only handover according to normal L3 Mobility, but also handover (cell transition, addition, or change) according to LTM or CPAC.

[0057] When cell selection according to LTM or CPAC fails, the RLF / HO reporting unit 220 may transmit information indicating the failure of LTM or CPAC to the network. Specifically, the RLF / HO reporting unit 220 may include the information in an RLF report or a handover failure report. The RLF / HO reporting unit 220 may transmit an RRC layer message (e.g., RRC Reconfiguration Complete) including the RLF report or the handover failure report to the network.

[0058] The RLF / HO reporting unit 220 may transmit to the network the time from receiving a configuration instruction to execute CPAC without initializing information about the SCell to failure of the SCell addition / change according to CPAC. The operation of executing CPAC without initializing information about the SCell may be referred to as subsequent CPAC, as described above. The RLF / HO reporting unit 220 may report to the network the elapsed time from receiving the subsequent CPAC configuration (config.) to failure of the SCell addition or change by the conditional PSCell addition / change. An RLF report or a handover failure report may be used for this report.

[0059] Furthermore, the RLF / HO reporting unit 220 may transmit, to the network, identification information of candidate target cells to be transferred that are added or changed according to CPAC. As described above, the wireless communication system 10 may support CPAC fast failure recovery. In particular, when CPAC fast failure recovery is applied, the RLF / HO reporting unit 220 may transmit identification information (e.g., cell ID) of the candidate target cells. Note that the identification information may be a Physical Cell ID (PCI) or another logical CID, as long as it can identify the cell.

[0060] The RLF / HO reporting unit 220 may transmit to the network the time from the completion of the previous cell selection according to LTM or CPAC to the failure or success of cell selection. Specifically, the RLF / HO reporting unit 220 may report to the network the elapsed time from the completion of the previous cell selection according to LTM or CPAC to the failure or success of the next cell selection. For this report, an RLF report, a handover failure report, or a successful handover report may be used.

[0061] Furthermore, the RLF / HO reporting unit 220 may transmit to the network at least one of the time from the reception of the configuration instruction to execute LTM (Subsequent LTM) without initializing information about the candidate target cells until the failure or success of cell selection according to LTM, and the number of cell selection attempts from the reception of the configuration instruction to execute LTM (Subsequent LTM) without initializing information about the candidate target cells until the failure or success of cell selection according to LTM.

[0062] Specifically, the RLF / HO reporting unit 220 may report to the network the elapsed time from the reception of the subsequent LTM setting instruction until the cell selection according to the LTM fails or succeeds. Also, the RLF / HO reporting unit 220 may report to the network the number of cell selections performed from the reception of the subsequent LTM setting instruction until the cell selection according to the LTM fails or succeeds. For this report, an RLF report, a handover failure report, or a successful handover report may be used.

[0063] The RLF / HO reporting unit 220 may transmit to the network at least one of the time from receiving a configuration instruction to perform CPAC without initializing information about the candidate target cell (Subsequent CPAC) to the failure or success of adding / changing the SCell according to CPAC, and the number of additions / changes performed from receiving a configuration instruction to perform CPAC without initializing information about the candidate target cell (Subsequent CPAC) to the failure or success of adding / changing the SCell according to CPAC.

[0064] Specifically, the RLF / HO reporting unit 220 may report to the network the elapsed time from the reception of the Subsequent CPAC configuration instruction until the failure or success of the SCell addition / modification in accordance with CPAC. Furthermore, the RLF / HO reporting unit 220 may report to the network the number of attempts to add / modify the SCell from the reception of the Subsequent CPAC configuration instruction until the failure or success of the SCell addition / modification in accordance with CPAC. For this report, an RLF report, a handover failure report, or a successful handover report may be used.

[0065] The handover execution unit 230 executes handover of the UE 200. Specifically, the handover execution unit 230 may execute handover to a transfer destination cell (NG-RAN node) based on control by the gNB 100.

[0066] Furthermore, the handover execution unit 230 may execute handover according to not only L3 Mobility but also L1 / L2 Mobility. Handover may be interpreted as transition, cell transition, cell selection, etc. Specifically, the handover execution unit 230 may execute handover based on L1 / L2 Mobility based on at least one command of layer 1 and / or layer 2.

[0067] The type of the command is not particularly limited, but may be, for example, an L1 / L2 Mobility command. The L1 / L2 Mobility command may be replaced with another command of the RRC layer.

[0068] Specifically, the handover executing unit 230 may transmit an RRC Reestablishment Request to the network (gNB 100). Here, the destination of the RRC Reestablishment Request may be a CU or a DU. Note that the message is not necessarily limited to an RRC Reestablishment Request, and may be another message (for example, an RRC Resume Request) as long as it requests reconnection in the RRC layer.

[0069] Furthermore, the handover execution unit 230 may execute the handover in accordance with CPAC, which may mean either conditional PSCell addition or conditional PSCell change.

[0070] The control unit 240 controls each functional block constituting the UE 200. Specifically, the control unit 240 can execute control related to handover of the UE 200. Specifically, the control unit 240 can execute cell selection (handover) in accordance with lower layer mobility control (LTM) or secondary cell addition and change procedure (CPAC).

[0071] Specifically, the control unit 240 can execute L1 / L2 Mobility (LTM), that is, mobility control of at least one of layer 1 and layer 2. Mobility control by L1 / L2 Mobility may include quality measurement of service areas and neighboring cells in layer 1 or layer 2, setting of destination candidate cells, cell reselection (transition), handover, etc. In this way, the control unit 240 can execute handover in accordance with mobility control by a lower layer.

[0072] The control unit 240 can select a cell as a transfer destination when L1 / L2 Mobility (LTM) fails (LTM failure). Note that an LTM failure may include a failure in a measurement or transfer (handover) procedure associated with a cell transfer by LTM.

[0073] Furthermore, when the selected cell is a candidate target cell of the handover destination, the control unit 240 may apply the configuration of the candidate target cell without transmitting an RRC layer message to the network. Specifically, when LTM fast failure recovery or CPAC fast failure recovery is applied and the selected cell is one of multiple candidate target cells of the handover destination, the control unit 240 may omit transmitting an RRC message and apply the configuration of the candidate target cell.

[0074] The control unit 240 may receive a cell ID of a cell recovered by LTM fast failure recovery (while timer T311 is running after an LTM failure, the control unit 240 causes the handover execution unit 230 to execute cell selection, and if the selected cell is a candidate target cell, the control unit 240 may directly apply the LTM configuration of the cell without transmitting an RRC Reestablishment Request to the gNB 100.

[0075] The ID of the cell may be reported to the network by the RLF / HO reporting unit 220 as described above. The cell ID may also be referred to as an LTM Cell ID. Timer T311 starts at the start of the RRC connection re-establishment procedure and stops when an appropriate NR cell or a cell using another RAT is selected.

[0076] Similarly, for CPAC, when the selected cell is a candidate target cell, the control unit 240 may directly apply the CPAC configuration of the selected cell without transmitting an RRC Reestablishment Request to the gNB 100. Note that, in the case of CPAC, the operation related to timer T311 may be excluded.

[0077] (3) Operation of the Wireless Communication System Next, a description will be given of the operation of the wireless communication system 10. Specifically, a description will be given of the operation of the UE 200 reporting detailed information on the execution of LTM and CPAC to the network.

[0078] (3.1) Assumptions and Issues Figure 5 shows an example sequence of an RLF report / handover failure report. As shown in Figure 5, when a UE detects a radio link failure (RLF), it transmits and receives RRC layer messages to and from a gNB and may transmit an RRC Reconfiguration Complete including an indication that an RLF report / handover failure report is available for transmission. The UE may report an RLF report / handover failure report in a UE information response. A successful handover report may also be included.

[0079] The gNB may be notified by other RRC layer messages (RRC Setup Complete, RRC Reconfiguration Complete, RRC Resume Complete, etc.) that it can transmit an RLF report, handover failure report, or successful HO information.

[0080] To realize the enhancement of Self-Organizing Networks (SON) regarding LTM and CPAC, it is considered important for the UE to report detailed information regarding the execution of LTM and CPAC to the network. However, the current 3GPP specifications do not allow the UE to report such detailed information to the network.

[0081] Specifically, when an LTM failure, a subsequent LTM failure, or a subsequent CPAC failure occurs, the UE cannot report the details of the failure to the network.

[0082] (3.2) Example of Operation Below, an example of UE operation that can solve the above-mentioned problem will be described. The UE may transmit an RLF report including the following information to the network (gNB):

[0083] Cell ID of the cell recovered by LTM fast failure recovery: After an LTM failure, while timer T311 is running, the UE performs cell selection. If the selected cell is a candidate target cell, the UE may directly apply the LTM configuration of the cell without sending an RRC Reestablishment Request to the gNB. In this case, the UE may report the cell ID of the cell to the network. This cell ID may be referred to as the LTM Cell ID.

[0084] An indication that the HO failure is a failure of a subsequent CPAC or subsequent LTM. The elapsed time from when the UE receives a subsequent CPAC configuration from the network to when the PSCell change or PSCell addition fails. Figure 6 shows an example of the elapsed time from when the UE receives a subsequent CPAC configuration from the network to when the PSCell change or PSCell addition fails. As shown in Figure 6, the UE may report to the network the elapsed time from when the subsequent CPAC configuration is received to when the CPAC fails. The elapsed time may include one or more successful CPACs.

[0085] - Time elapsed from the completion of the previous LTM execution to the LTM failure Figure 7 shows an example of the time elapsed from the completion of the previous LTM execution to the LTM failure. As shown in Figure 7, the UE may report the time elapsed from the completion of the previous LTM execution to the LTM failure to the network. The elapsed time may include one or more successful LTMs.

[0086] - The elapsed time from the completion of the previous LTM (previous LTM) execution to the failure of LTM fast failure recovery - The elapsed time from the completion of the previous LTM (previous LTM) execution to the success of LTM fast failure recovery - The elapsed time from the completion of the previous CPAC (previous CPAC) execution to the failure of PSCell change or PSCell addition Figure 8 shows an example of the elapsed time from the completion of the previous CPAC execution to the failure of PSCell change or PSCell addition. As shown in Figure 8, the UE may report to the network the elapsed time from the completion of the previous CPAC execution to the CPAC failure. The elapsed time may include one or more successful CPACs.

[0087] Figure 9 shows an example of the elapsed time between the UE receiving the subsequent LTM configuration from the network and the LTM failure. As shown in Figure 9, the UE may report the elapsed time between the reception of the subsequent LTM configuration from the network and the LTM failure to the network. The elapsed time may include one or more successful LTMs.

[0088] - The time elapsed from when the UE receives a subsequent LTM configuration from the network until the failure of LTM fast failure recovery. - The time elapsed from when the UE receives a subsequent LTM configuration from the network until the success of LTM fast failure recovery. - The number of times that the UE executes CPAC (successful times) from when the UE receives a subsequent CPAC configuration from the network until the failure of PSCell change or PSCell addition. - The number of times that the UE executes LTM successfully from when the UE receives a subsequent LTM configuration from the network until the failure of LTM. - The number of times that the UE executes LTM failure recovery (which may include LTM fast failure recovery) from when the UE receives a subsequent LTM configuration from the network until the failure of LTM fast failure recovery. - The number of times that the UE executes LTM from when the UE receives a subsequent LTM configuration from the network until the failure of LTM fast failure recovery. - The number of times that the UE executes LTM from when the UE receives a subsequent LTM configuration from the network until the failure of LTM fast failure. According to the above-described operation, when an LTM failure, a subsequent LTM failure, or a subsequent CPAC failure occurs, the UE can report detailed information about the failure to the network. This allows the network to construct a SON using the detailed information. In other words, the above-described UE can report information necessary for extending the SON regarding LTM and CPAC.

[0089] Specifically, the UE can transmit information indicating that LTM or CPAC has failed to the network, which allows the network to reliably recognize that an LTM or CPAC failure has occurred in the area (cell) where the UE is located, and this can contribute to establishing SON.

[0090] In addition, the UE can report the elapsed time or the number of times LTM or CPAC has been performed to the network, as described above, so that the network can reliably recognize the detailed status of LTM or CPAC in the area (cell) where the UE is located, which can contribute to establishing SON.

[0091] (4) 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.

[0092] For example, in the above-mentioned operation example, an example sequence between a UE and a gNB was described, but similar operations may also be performed between an IAB donor node and an IAB node (Mobile Termination (MT)) in an Integrated Access and Backhaul (IAB) that integrates wireless access to a terminal (User Equipment, UE) and wireless backhaul between wireless communication nodes such as a radio base station (gNB).

[0093] 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 be interchangeable.

[0094] Furthermore, specific, dedicated, UE-specific, and UE-dedicated may be interchangeable. Similarly, common, shared, group-common, UE-common, and UE-shared may be interchangeable.

[0095] The block diagrams (FIGS. 3 and 4) 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 also be realized by combining the single device or multiple devices with software.

[0096] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, 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.

[0097] Furthermore, the above-described gNB100 and UE200 (the devices) may function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 10 is a diagram showing an example of the hardware configuration of the devices. As shown in Figure 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.

[0098] 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.

[0099] Each functional block of the device (see FIGS. 3 and 4) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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).

[0107] 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).

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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), a 6th generation mobile communication system (6G), an xth generation mobile communication system (xG) (where x is, for example, an integer or a decimal), 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 with 5G) may also be applied.

[0112] 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.

[0113] 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 (e.g., MME or 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 (e.g., MME and S-GW) may also be used.

[0114] 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 and output via multiple network nodes.

[0115] 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 to. The output information may be deleted. The input information may be transmitted to another device.

[0116] 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).

[0117] 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).

[0118] 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.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] 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)).

[0127] 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.

[0128] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0129] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0130] 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.

[0131] 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.

[0132] 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 (or sidelink).

[0133] 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.

[0134] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0135] 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.

[0136] 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.

[0137] 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.

[0138] 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.

[0139] 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 called a slot, minislot, etc., instead of a subframe.

[0140] 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.

[0141] 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.

[0142] 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, and the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0143] A TTI having a time length of 1 ms may be referred to as 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 referred to as a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0144] 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.

[0145] 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.

[0146] 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, each of which may consist of one or more resource blocks.

[0147] 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.

[0148] 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.

[0149] 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.

[0150] 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.

[0151] 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."

[0152] 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 may be changed in various ways.

[0153] 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.

[0154] The reference signal may also be abbreviated as Reference Signal (RS) and may be called a pilot depending on the applicable standard.

[0155] 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."

[0156] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] 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."

[0162] 11 shows an example of the configuration of a vehicle 2001. As shown in Fig. 11, 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.

[0163] The drive unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also 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. The electronic control unit 2010 is composed of a microprocessor 2031, memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals from various sensors 2021 to 2027 provided in the vehicle are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0164] 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.

[0165] 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 (outputting) 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 acquired 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.

[0166] The information service unit 2012 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0167] 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.

[0168] 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.

[0169] 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.

[0170] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021 to 2028 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021 to 2028, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0171] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle-to-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle. The information service unit 2012 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from 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, axles 2009, sensors 2021 to 2028, and the like provided in the vehicle 2001.

[0172] 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.

[0173] (Additional Note) The above disclosure may be expressed as follows: A first feature is a terminal including: a control unit that executes cell selection in accordance with a mobility control procedure or a secondary cell addition / change procedure by a lower layer; and a transmission unit that transmits information related to the cell selection to a network, wherein, when the cell selection fails, the transmission unit transmits information indicating a failure of the mobility control or the addition / change procedure to the network.

[0174] A second feature is a terminal that includes a control unit that performs cell selection in accordance with a procedure for adding or changing a secondary cell, and a transmission unit that transmits information related to the cell selection to a network, and the transmission unit transmits to the network the time from receiving a setting instruction to perform the addition or change procedure without initializing information related to the secondary cell to failure of adding or changing the secondary cell in accordance with the addition or change procedure.

[0175] A third feature is a terminal that includes a control unit that performs cell selection in accordance with mobility control by a lower layer or a procedure for adding or changing a secondary cell, and a transmission unit that transmits information related to the cell selection to a network, wherein, if the selected cell is a candidate target cell to be transitioned to, the control unit applies the configuration of the candidate target cell without transmitting a message of a radio resource control layer to the network, and the transmission unit transmits identification information of the candidate target cell to the network.

[0176] A fourth feature, in any one of the first to third features, is that the transmitter transmits, to the network, a time period from completion of the previous cell selection to failure or success of the cell selection.

[0177] A fifth feature is that, in the first to fourth features, the transmitter transmits to the network at least one of a time from reception of a setting instruction to execute the mobility control without initializing information about the candidate target cells to failure or success of the cell selection in accordance with the mobility control and a number of times the cell selection is executed from reception of a setting instruction to execute the mobility control without initializing information about the candidate target cells to failure or success of the cell selection in accordance with the mobility control.

[0178] A sixth feature is that, in the first to fourth features, the transmitter transmits to the network at least one of a time from receiving a setting instruction to execute the addition / change procedure without initializing information about the candidate target cell to failure or success of adding / changing the secondary cell in accordance with the addition / change procedure, and a number of times the addition / change is executed from receiving a setting instruction to execute the addition / change procedure without initializing information about the candidate target cell to failure or success of adding / changing the secondary cell in accordance with the addition / change procedure.

[0179] 10 Wireless communication system 20 NG-RAN 100 gNB 110 Wireless communication unit 120 Handover processing unit 130 Measurement setting unit 140 Control unit 200 UE 210 Wireless communication unit 220 RLF / HO reporting unit 230 Handover execution unit 240 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 section 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port

Claims

1. A terminal comprising: a control unit that executes cell selection in accordance with mobility control by a lower layer or a procedure for adding or changing a secondary cell; and a transmission unit that transmits information regarding the cell selection to a network, wherein if the cell selection fails, the transmission unit transmits information indicating that the mobility control or the procedure for adding or changing a secondary cell has failed to the network.

2. A terminal comprising: a control unit that executes cell selection in accordance with a procedure for adding or changing a secondary cell; and a transmission unit that transmits information regarding the cell selection to a network, wherein the transmission unit transmits to the network the time from receiving a setting instruction to execute the addition or change procedure without initializing information regarding the secondary cell to failure of adding or changing the secondary cell in accordance with the addition or change procedure.

3. A terminal comprising: a control unit that performs cell selection in accordance with mobility control by a lower layer or a procedure for adding or changing a secondary cell; and a transmission unit that transmits information regarding the cell selection to a network, wherein if the selected cell is a candidate target cell to which the terminal is to transition, the control unit applies the configuration of the candidate target cell without transmitting a message of a radio resource control layer to the network, and the transmission unit transmits identification information of the candidate target cell to the network.

4. The terminal according to any one of claims 1 to 3, wherein the transmission unit transmits to the network the time from the completion of the previous cell selection until the failure or success of the cell selection.

5. The terminal according to claim 3, wherein the transmitting unit transmits to the network at least one of the time from receiving a setting instruction to execute the mobility control without initializing information about the candidate target cell to failure or success of the cell selection in accordance with the mobility control, and the number of times the cell selection is performed from receiving a setting instruction to execute the mobility control without initializing information about the candidate target cell to failure or success of the cell selection in accordance with the mobility control.

6. The terminal according to claim 3, wherein the transmitting unit transmits to the network at least one of the time from receiving a setting instruction to execute the addition / change procedure without initializing information about the candidate target cell to failure or success of adding / changing the secondary cell in accordance with the addition / change procedure, and the number of times the addition / change is executed from receiving a setting instruction to execute the addition / change procedure without initializing information about the candidate target cell to failure or success of adding / changing the secondary cell in accordance with the addition / change procedure.

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