Terminal and wireless base station

Abstract

A terminal according to the present invention performs wireless communication with a wireless base station over a wireless link. The terminal uses a learning model to predict at least one of the timing and the probability of a consecutive out-of-sync at the wireless link and transmits the prediction results to a network.　

Description

Terminals and wireless base stations

[0001] The present disclosure relates to a terminal and a radio base station that use an AI / ML model.

[0002] The 3rd Generation Partnership Project (3GPP: registered trademark) has developed specifications for Long Term Evolution (LTE) and 5th generation mobile communication systems (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] 3GPP Release 19 has formulated a work item (WI) on artificial intelligence / machine learning models (AI / ML models) (see Non-Patent Document 1). For example, it is expected that AI / ML models will be used to predict handover failures (HOFs) of terminals (User Equipment, UEs) and the occurrence of radio link failures (RLFs), which may include beam failures (BFs).

[0004] Furthermore, because the occurrence frequency of RLF is low and it is difficult to obtain high learning accuracy even when using an AI / ML model, a method of predicting the occurrence of RLF from the predicted quality of the serving cell (which may be called Study Indirect) is also being studied, rather than directly predicting the occurrence of RLF using an AI / ML model (which may be called Study Direct) (Non-Patent Document 2).

[0005] "Revised SID on AIML for mobility in NR", RP-240082, 3GPP TSG RAN Meeting #103, 3GPP, March 2024 "Draft Report of 3GPP TSG RAN WG2 meeting #126 Fukuoka, Japan", 3GPP TSG-RAN WG2 meeting #127, 3GPP, May 2024

[0006] As mentioned above, it is expected that RLF (which may include BF) will be predicted using an AI / ML model. However, currently, UEs (or radio base stations (gNBs)) are unable to determine the specific target (content) of RLF prediction, which means that effective performance improvement using an AI / ML model cannot be expected.

[0007] Therefore, the following disclosure has been made in consideration of the above circumstances, and aims to provide a terminal and a radio base station that can realize accurate RLF (or BF) prediction using an AI / ML model.

[0008] One aspect of the present disclosure is a terminal (UE200) that includes a communication unit (wireless communication unit 210) that performs wireless communication with a wireless base station via a wireless link, a control unit (control unit 240) that uses a learning model to predict at least one of the timing and probability of consecutive occurrences of out-of-synchronization of the wireless link, and a transmission unit (AI / ML model unit 215) that transmits the prediction result by the control unit to a network.

[0009] One aspect of the present disclosure is a terminal (UE200) that includes a communication unit (wireless communication unit 210) that performs wireless communication with a wireless base station using an antenna beam, a control unit (control unit 240) that uses a learning model to predict at least one of the timing at which a fault indication for the antenna beam will be obtained from a lower layer and the probability of obtaining the fault indication, and a transmission unit (AI / ML model unit 215) that transmits the prediction result by the control unit to a network.

[0010] FIG. 1 is a diagram showing an overall schematic configuration of a wireless communication system 10. FIG. 2 is a functional block configuration diagram of a gNB 100. FIG. 3 is a functional block configuration diagram of a UE 200. FIG. 4 is a diagram showing an example of the functional architecture of an AI / ML model. FIG. 5 is a diagram showing an example of a handover sequence based on the RLF prediction result using an AI / ML model. FIG. 6 is a diagram showing an example of setting a block error rate for determining loss of synchronization and establishment of synchronization. FIG. 7 is a diagram showing an example 1 of a prediction operation of an RLF (BF) using an AI / ML model. FIG. 8 is a diagram showing an example 2 of a prediction operation of an RLF (BF) using an AI / ML model. FIG. 9 is a diagram showing an example of the hardware configuration of a gNB 100 and a UE 200. FIG. 10 is a diagram showing an example of the configuration of a vehicle 2001.

[0011] 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.

[0012] (1) Overall Schematic Configuration of Wireless Communication System Fig. 1 is an overall schematic configuration diagram 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).

[0013] The wireless communication system 10 may be a wireless communication system conforming to a standard called Beyond 5G, 5G Evolution, or 6G, or may include a wireless communication system conforming to a standard 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). The wireless communication system 10 may also be configured using multiple radio access technologies (RATs), for example, 4G / LTE and 5G.

[0014] 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 .

[0015] 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.

[0016] The NG-RAN 20 actually includes multiple NG-RAN nodes, specifically, gNBs (or ng-eNBs), and is connected to a 5G-compliant core network (5GC, not shown). The 5GC (CN) may introduce the concept of CUPS (Control and User Plane Separation), which clearly separates the functions of the user plane and the control plane.

[0017] The NG-RAN 20 may be connected to the OAM / RIC 40 and the NF 50 via 5GC or directly from the NG-RAN 20. The OAM / RIC 40 (network device) can provide functions related to operation and maintenance (OAM) of the wireless communication system 10. The OAM / RIC 40 can also provide functions related to control of the NG-RAN 20 (RIC: RAN Intelligent Controller). The specific functions of the RIC are defined by the O-RAN specifications (e.g., O-RAN Architecture-Description 6.0). In this embodiment, the OAM / RIC 40 may constitute an entity that performs operation, maintenance, or control.

[0018] The NF 50 may be interpreted as a logical node that provides a network function. The NF 50 may include an Access and Mobility Management Function (AMF) that is included in the 5G system architecture and provides access and mobility management functions for the UE 200, a Session Management Function (SMF) that provides session management functions, and a Location Management Function (LMF) that controls communications related to location-based services defined in 5GC. Furthermore, a UDM / UDR (Unified Data Management / User Data Repository) may be connected to the AMF and / or SMF. The NG-RAN 20 and 5GC may simply be referred to as a "network."

[0019] In addition, the NG-RAN 20 may be connected to a server managed by a 3GPP service provider or a server (3GPP or non-3GPP server) managed by a party other than the provider.

[0020] The gNB100 is a radio base station conforming to NR and performs radio communication with the UE200 conforming to NR. The gNB100 may be configured with 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.

[0021] The gNB 100 and the UE 200 can support Massive MIMO, which generates a more directional beam BM by controlling radio signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which aggregates multiple component carriers (CCs), and Dual Connectivity (DC), which simultaneously communicates between the UE and multiple NG-RAN nodes. The UE 200 may also perform handover (HO) to a different RAT.

[0022] In the wireless communication system 10, artificial intelligence (AI) / machine learning (ML) may be applied in the NG-RAN 20. Specifically, a learning model (herein referred to as an AI / ML model) may be used to optimize the mobility or handover (which may also be read as transition, cell transition, cell selection, cell reselection, etc.) of the UE 200.

[0023] The AI / ML model may be expressed by another term meaning AI or ML, such as an artificial intelligence (AI) model or a machine learning (ML) model. In the wireless communication system 10, such an AI / ML model can be used to optimize the mobility or handover of the UE 200. The AI / ML model may be provided in the OAM / RIC 40 or the gNB 100. Alternatively, the AI / ML model may be provided in the UE 200.

[0024] In the wireless communication system 10, in addition to mobility management of the UE 200 at layer 3 (which may include, for example, a radio resource control layer (RRC)), mobility management at layer 1 / layer 2 (which may include, for example, a medium access control layer (MAC)) (which may also be referred to as L1 / L2 mobility or LTM) may be applied.

[0025] In the wireless communication system 10, not only mobility control of the UE 200 at layer 3 (which may be referred to as L3 mobility), but also mobility control at layer 1 and / or layer 2 (L1 / L2 mobility) may be applied. L3 mobility may be interpreted as mobility control at the radio resource control layer (RRC). On the other hand, 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).

[0026] 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.

[0027] The UE 200 may periodically perform measurement reporting. The UE 200 may perform measurement reporting for each event. An entering condition for starting measurement reporting and a leaving condition for ending measurement reporting may be defined for each event. The existing events may include the following events (see 3GPP TS38.331). Note that the entering condition may be interpreted as a condition for determining whether or not to include a measurement report target, and the leaving condition may be interpreted as a condition for determining whether or not to exclude a measurement report target.

[0028] (i) Event A1 (Serving becomes better than threshold) Event A1 is an event in which the reception quality of the serving cell becomes better than a threshold. For example, the entering condition is Ms - Hys > Thresh, and the leaving condition is Ms + Hys < Thresh.

[0029] Here, Ms is the reception quality of the serving cell, Hys is a hysteresis parameter, and Thresh is a threshold value.

[0030] (ii) Event A2 (Serving Becomes Worse Than Threshold) Event A2 is an event in which the reception quality of the serving cell becomes worse than a threshold. For example, the entering condition is Ms + Hys < Thresh, and the leaving condition is Ms - Hys > Thresh.

[0031] Here, Ms is the reception quality of the serving cell, Hys is a hysteresis parameter, and Thresh is a threshold value.

[0032] (iii) Event A3 (Neighbor becomes offset better than SpCell) Event A3 is an event in which the reception quality of a neighboring cell becomes offset better than the reception quality of the serving cell. For example, the entering condition is Mn + Ofn + Ocn - Hys > Mp + Ofp + Ocp + Off, and the leaving condition is Mn + Ofn + Ocn + Hys < Mp + Ofp + Ocp + Off.

[0033] where Mn is the reception quality of the neighboring cell, Ofn is the offset specific to the measurement object, and Ocn is the offset specific to the cell. Mp is the reception quality of the serving cell, Ofp is the offset specific to the measurement object, and Ocp is the offset specific to the cell. Hys is the hysteresis parameter, and Off is the parameter used in Event A3.

[0034] (iv) Event A4 (Neighbor becomes better than threshold) Event A4 is an event in which the reception quality of a neighboring cell becomes better than a threshold. For example, the entering condition is Mn + Ofn + Ocn - Hys > Thresh, and the leaving condition is Mn + Ofn + Ocn + Hys < Thresh.

[0035] where Mn is the reception quality of the neighboring cell, Ofn is an offset specific to the measurement object, Ocn is an offset specific to the cell, Hys is a hysteresis parameter, and Thresh is a threshold value.

[0036] (v) Event A5 (SpCell becomes worse than threshold1 and neighbor becomes better than threshold2) Event A5 is an event in which the reception quality of the serving cell becomes worse than a threshold and the reception quality of the neighboring cell becomes better than a threshold. For example, the entering condition is Mp + Hys < Thresh1 and Mn + Ofn + Ocn - Hys > Thresh2, and the leaving condition is Mp - Hys > Thresh1 and Mn + Ofn + Ocn + Hys < Thresh2.

[0037] where Ms is the receiving quality of the serving cell, Hys is a hysteresis parameter, Thresh1 is a threshold, Mn is the receiving quality of the neighboring cell, Ofn is a measurement object-specific offset, and Ocn is a cell-specific offset, Hys is a hysteresis parameter, and Thresh2 is a threshold.

[0038] (vi) Event A6 (Neighbor becomes offset better than SCell) Event A6 is an event in which the reception quality of a neighboring cell becomes offset better than the reception quality of an SCell (Secondary Cell). For example, the entering condition is Mn + Ocn - Hys > Ms + Ocs + Off, and the leaving condition is Mn + Ocn + Hys < Ms + Ocs + Off.

[0039] In addition to the events described above, events related to RATs (Radio Access technologies) (e.g., B1 (Inter RAT neighbor becomes better than threshold), B2 (Serving becomes worse than threshold1 and inter RAT neighbor becomes better than threshold2)) may be included.

[0040] Here, Mn is the reception quality of the neighboring cell, Ocn is a cell-specific offset, Ms is the reception quality of the SCell, Ocs is a cell-specific offset, Hys is a hysteresis parameter, and Off is a parameter used in Event A6.

[0041] (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. 2 is a functional block configuration diagram of the gNB 100. Fig. 3 is a functional block configuration diagram of the UE 200.

[0042] (2.1) gNB100 As shown in FIG. 2, the gNB100 includes a wireless communication unit 110, a handover processing unit 120, an AI / ML model unit 130, and a control unit 140.

[0043] The wireless communication unit 110 transmits downlink signals (DL signals) conforming to NR. The wireless communication unit 110 also receives uplink signals (UL signals) conforming to NR. The wireless communication unit 110 may transmit DL signals and receive UL signals using one or more transmission / reception points (TRPs). The TRPs of the wireless communication unit 110 may be interpreted as meaning multiple DL transmission antennas or multiple UL reception antennas.

[0044] The wireless communication unit 110 may perform wireless communication with the UE 200 via a wireless link (RL). The wireless communication unit 110 may also perform wireless communication with the UE 200 using an antenna beam. In this embodiment, the wireless communication unit 110 may constitute a communication unit.

[0045] The radio link may be interpreted as a physical or logical communication path established between the gNB 100 and the UE 200. In a broad sense, the radio link may be interpreted as being similar to a radio bearer (e.g., a Signaling Radio Bearer (SRB) or a Data Radio Bearer (DRB)).

[0046] An antenna beam (beam BM, see FIG. 1) may be simply referred to as a beam, and the terms QCL (Quasi-Colocation) / TCI (Transmission Configuration Indication) state / beam may be interchangeable. QCL may be interpreted as, for example, two antenna ports being quasi-colocated when the characteristics of the channel through which symbols on one antenna port are carried can be inferred from the channel through which symbols on the other antenna port are carried.

[0047] The wireless communication unit 110 may transmit multiple antenna beams with different transmission directions and widths (thicknesses). Also, the wireless communication unit 110 may respond to multiple antenna beams transmitted from different directions and receive the antenna beams.

[0048] The handover processing unit 120 executes handover of the UE 200. Specifically, the handover processing unit 120 executes handover of the UE 200 from a serving cell to another nearby cell.

[0049] 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 (connected state in the radio resource control layer) 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.

[0050] The handover may also include a conditional handover (CHO) and / or a dual active protocol stack (DAPS) handover. CHO can execute a handover initiated by the UE 200 when a specific execution condition is met. If CHO is not applicable, a normal handover may be executed (which may be called CHO recovery). In CHO recovery, the UE 200 executes cell selection after a CHO failure. If a CHO candidate cell is selected, the UE 200 can directly apply conditional RRC Reconfiguration of the selected cell to reconnect without transmitting an RRC Reestablishment Request to the candidate target cell.

[0051] The execution condition may consist of one or two trigger conditions (CHO event A3 / A5 specified in 3GPP TS38.331). A single reference signal (RS) type may be triggered, and up to two different trigger quantities (e.g., Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ), RSRP and Signal-to-Interference plus Noise power Ratio (SINR)) may be simultaneously set for the evaluation of the CHO execution condition for a single candidate cell.

[0052] The AI / ML model unit 130 executes a process using a learning model (AI / ML model). Specifically, the AI / ML model unit 130 executes a process using an AI / ML model that is applied to optimization of mobility and / or handover of the UE 200.

[0053] In particular, in this embodiment, the AI / ML model unit 130 may predict content related to radio link failure (RLF) and antenna beam failure (BF). The content related to RLF (which may include BF, the same applies hereinafter) may be any indicator related to RLF, and may typically include the timing of RLF occurrence, the frequency (probability) of occurrence, and the correlation between the quality of the serving cell and neighboring cells and the RLF.

[0054] The AI / ML model unit 130 may transmit a measurement configuration (MeasConfig) that configures measurements using the AI / ML model to the UE 200. The measurement configuration may be transmitted to the UE 200 by, for example, a message of a radio resource control layer (RRC).

[0055] The AI / ML model unit 130 may receive a measurement report (Measurement Report) including measurement results generated by applying the AI / ML model to a measurement object (MeasObject) included in the measurement configuration from the UE 200. Targets predicted by the AI / ML model may include, for example, quality measurements (such as a cell quality measurement value (RSRP)), a probability of handover failure (HOF), a probability of radio link failure (RLF), and the like.

[0056] Furthermore, the AI / ML model unit 130 may receive a prediction result of content related to RLF (BF) by the AI / ML model from the UE 200. The prediction result may be reported as part of a Measurement Report or may be reported as a report related to AI / ML (AI / ML reporting).

[0057] The control unit 140 controls each functional block constituting the gNB 100. In particular, in this embodiment, the control unit 140 may use the AI / ML model unit 130 to predict at least one of the timing and the probability of consecutive occurrence of out-of-sync of the radio link in the UE 200.

[0058] Furthermore, the control unit 140 may use the AI / ML model unit 130 to predict at least one of the timing at which the UE 200 acquires a beam failure instance indication of an antenna beam received from the gNB 100 from a lower layer and the probability of acquiring the failure indication. The lower layer here may refer to a layer located relatively lower than a layer (e.g., RLC, RRC) that recognizes and processes the beam failure instance indication, and may include MAC, PHY, etc. Specific examples of prediction target content related to RLF (BF) will be described further below.

[0059] In addition, the control unit 140 may use the AI / ML model unit 130 to obtain predicted values ​​such as cell quality measurements, HOF probability, and RLF (BF) probability, and perform control related to SON (Self-Organizing Networks) based on the predicted values ​​and the accuracy of the predicted values.

[0060] Furthermore, the control unit 140 may perform mobility control of the UE 200, including handover, based on the cell quality measurement results and HOF / RLF reports (which may include prediction results using an AI / ML model) acquired from the UE 200. The measurement results and reports may be predicted using an AI / ML model.

[0061] 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).

[0062] The data channels include a physical downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH).

[0063] 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.

[0064] (2.2) UE 200 As shown in FIG. 3 , the UE 200 includes a radio communication unit 210, an AI / ML model unit 215, a measurement processing unit 220, a handover execution unit 230, and a control unit 240.

[0065] The wireless communication unit 210 transmits uplink signals (UL signals) conforming to NR. The wireless communication unit 210 also receives uplink signals (DL signals) conforming to NR. The wireless communication unit 210 may receive DL signals and transmit UL signals using one or more transmission / reception points (TRPs). The TRPs of the wireless communication unit 210 may be interpreted as meaning multiple UL transmission antennas or multiple DL reception antennas.

[0066] The wireless communication unit 210 may perform wireless communication with the gNB100 (wireless base station) via a wireless link (RL). The wireless communication unit 210 may also perform wireless communication with the gNB100 using an antenna beam. In this embodiment, the wireless communication unit 210 may constitute a communication unit.

[0067] The AI / ML model unit 215 executes processing using a learning model (AI / ML model). The AI / ML model unit 215 may have the same functions as the AI / ML model unit 130 of the gNB 100. The AI / ML model unit may be provided in either the gNB 100 or the UE 200, or may be provided in both.

[0068] In particular, in this embodiment, the AI / ML model unit 215 can predict the occurrence of handover failure (HOF) or radio link failure (RLF). For example, the AI / ML model unit 215 may predict the probability of HOF / RLF occurrence in a serving cell or a neighboring cell (which may also be referred to as an adjacent cell, a peripheral cell, etc.). Note that the probability of beam-level failure (BF) occurrence may also be included. The occurrence probability may be represented by a percentage or by multiple stages, etc.

[0069] The AI / ML model unit 215 may have the same functions as the AI / ML model unit 130 of the gNB 100 described above regarding RLF, BF, and HOF. The AI / ML model unit 215 may transmit to the network a prediction result regarding RLF, BF, and HOF (or any one of them) by the control unit 240 using the AI / ML model unit 215. In this embodiment, the AI / ML model unit 215 may constitute a transmission unit.

[0070] For example, the AI / ML model unit 215 may transmit a prediction result of content related to RLF (BF) by the AI / ML model to the gNB 100. As described above, the prediction result may be reported as part of a Measurement Report or may be reported as a report related to AI / ML (AI / ML reporting).

[0071] Furthermore, the AI / ML model unit 215 may transmit, to the network, capability information (UE capability information) of the UE 200. In particular, in this embodiment, the AI / ML model unit 215 may transmit, to the network, UE capability information related to RLF, BF, and HOF prediction using the AI / ML model.

[0072] The measurement processing 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 result to the network (Measurement Report). The measurement processing unit 220 can perform measurement reporting of the source cell and the target cell during handover.

[0073] 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.

[0074] 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.

[0075] Furthermore, the handover execution unit 230 can execute processes related to normal handover (legacy handover) and conditional handover (CHO).

[0076] In the case of CHO, the handover execution unit 230 may transition to the candidate cell when an execution condition is satisfied. As described above, the execution condition may be determined based on the quality of the reference signal (RS), specifically, the value of RSRP, RSRQ, or SINR.

[0077] In addition, the destination of the CHO may or may not be accompanied by an SCG. In other words, the destination cell of the CHO may be a single cell or may be composed of multiple cells (which may be read as a cell group) according to the DC.

[0078] Furthermore, the handover execution unit 230 can receive from the network a request for handover (Handover command) of the UE 200. In response to receiving the Handover command, the handover execution unit 230 may transition (handover) from a source cell of the handover source to a target cell of the handover destination.

[0079] The control unit 240 controls each functional block constituting the UE 200. In particular, in this embodiment, the control unit 240 may use the AI / ML model unit 215 to execute control related to the RLF (which may include the BF) and the HOF.

[0080] Specifically, the control unit 240 may predict the occurrence of handover failure (HOF) or radio link failure (RLF) using an AI / ML model. For example, the control unit 240 may predict at least one of the timing and probability of consecutive occurrence of out-of-sync of a radio link using the AI / ML model unit 215. Out-of-sync may refer to a state in which synchronization of the radio link cannot be established. On the other hand, in-sync may refer to a state in which synchronization of the radio link is established.

[0081] Furthermore, the control unit 240 may predict at least one of the timing of acquiring an antenna beam failure instance indication (beam failure instance indication) from a lower layer and the probability of acquiring the failure indication using the AI / ML model unit 215. As described above, the lower layer here may refer to a layer located relatively lower than the layer (e.g., RLC, RRC) that recognizes and processes the beam failure instance indication, and may include MAC, PHY, etc.

[0082] The control unit 240 may predict the time from the timing when out-of-sync occurs consecutively until it is determined that a radio link failure (RLF) has occurred. The control unit 240 may also predict the timing when a timer for detecting failure of an antenna beam (beam failure detection timer) is activated.

[0083] Specifically, the control unit 240 may perform the following operations regarding the prediction of RLF using the AI / ML model unit 215.

[0084] Predict the time or probability of a predetermined number of consecutive out-of-sync events occurring in a specific cell (which may be a serving cell or a neighboring cell including a candidate cell; the same applies below).

[0085] - Predict the interval (time period) from a predetermined number of consecutive out-of-sync events in a specific cell to the occurrence of RLF, and the probability of RLF occurring in that interval.

[0086] The period from a predetermined number of consecutive Out-of-Sync events to the occurrence of RLF is managed by timer T310 or a new timer.

[0087] - Predict the time or probability of activation of T310 or a new timer.

[0088] Furthermore, the control unit 240 may perform the following operations regarding the prediction of BF using the AI / ML model unit 215.

[0089] Predict the time or probability of receiving a predetermined number of beam failure instance indications from a lower layer in a specific cell.

[0090] - Predict the time or probability of activation of the beam failure detection timer in a specific cell.

[0091] - Predict the time when BFI (Beam Failure Indication)_COUNTER >= beamFailureInstanceMaxCount in a specific cell or the probability that BFI_COUNTER >= beamFailureInstanceMaxCount will occur.

[0092] - Predict the time or probability at which beam failure recovery will be triggered in a particular cell.

[0093] Predict the target beam index where BF occurs or the probability of occurrence of that index. This may be the index of the synchronization signal block (SS (Synchronization Signal) / PBCH (Physical Broadcast CHannel) Block) (SSB index) or the CSI-RS index.

[0094] The control unit 240 may also periodically report the prediction results, or may perform event-based reporting when an event occurs (event-based reporting). Event-based reporting may be performed when the probability of RLF occurrence is equal to or greater than a predetermined threshold (e.g., 60%, 70%, 80%, or 90%).

[0095] (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 relating to the prediction of the occurrence of RLF or BF using an AI / ML model.

[0096] (3.1) Example of the Configuration of an AI / ML Model Figure 4 shows an example of the functional architecture of an AI / ML model. As shown in Figure 4, the architecture may include the following functions:

[0097] Data collection: Providing input data for model training and model inference functions.

[0098] Model training: Train, validate, and test ML models. As part of the model testing procedure, model performance metrics may be generated.

[0099] The model training function may also be responsible for data preparation (data pre-processing and cleaning, formatting, transformation, etc.).

[0100] Model inference: Provides inference output (such as a prediction or decision). The model inference function may provide control of the model inference to the model management / performance monitoring function.

[0101] Model management / performance monitoring: Manage ML models and monitor model performance.

[0102] (3.2) Assumptions and Issues Because the occurrence frequency of RLF is low and it is difficult to obtain high learning accuracy even when using an AI / ML model, a method of predicting the occurrence of RLF from the predicted results of the quality of the serving cell (which may be called Study Indirect) may be applied, rather than directly predicting the occurrence of RLF using an AI / ML model (which may be called Study Direct).

[0103] As described above, it is possible to predict RLF (which may include BF; the same applies below) using an AI / ML model, but the specific target (content) of RLF prediction is not clear. Furthermore, it is also not clear how to report the results of RLF predictions. For these reasons, there is a problem in that it is not possible to effectively improve performance with regard to RLF using an AI / ML model.

[0104] (3.3) Operation Overview Figure 5 shows an example of a handover sequence based on the RLF prediction result using an AI / ML model. As shown in Figure 5, a gNB (cell) may determine whether to hand over the UE to another cell (cell B) based on the RLF / HOF / Beam failure prediction result reported from the UE.

[0105] For example, if a UE reports to a gNB an AIML prediction that RLF will occur in serving cell A in 5 minutes, the gNB can hand over the UE from cell A to cell B earlier.

[0106] (3.4) Operation Example 1 In the following, the UE performs RLF prediction using an AI / ML model, but as described above, the prediction may be performed by the gNB. Alternatively, the prediction may be performed by the network side (OAM, CN, SMO (Service Management and Orchestration Framework), RIC).

[0107] Although RLF is described as a target here, the prediction target may also include HOF, which may be interpreted as a radio link failure in a target cell (transfer destination cell, candidate cell).

[0108] 6 shows an example of setting the block error rate at which out-of-sync and in-sync are determined. As shown in FIG. 6, for example, the block error rate (BLER) at which out-of-sync is determined (considered) is out ) may be set to 10%, and the block error rate (BLER) at which synchronization is determined (considered) to be established (In-Sync) is in ) may be set to 2%. Such BLER settings are specified in 3GPP TS38.133, Chapter 8.1.1.

[0109] Fig. 7 shows a first example of a predicted operation of RLF (BF) using an AI / ML model. Fig. 8 shows a second example of a predicted operation of RLF (BF) using an AI / ML model.

[0110] First, the parameters related to the timers will be described. Timer T310 is started when a physical layer problem of a Special Cell (SpCell) is detected, that is, when consecutive out-of-sync indications N310 are received from the lower layer, and may be stopped when consecutive in-sync indications N311 are received from the lower layer of the SpCell, when RRCReconfiguration is received in reconfigurationWithSync for the cell group, when MobilityFromNRCommand is received, when rlf-TimersAndConstant is reconfigured, when a connection re-establishment procedure is started, when an MCG fault information procedure is started, and when an SCG is released.

[0111] T312 may be started when T312 is configured in an MCG and triggers a measurement report for a measurement ID for which T312 is configured and "useT312" is set to true during execution of T310 of a PCell, and when T312 is configured in an SCG and "useT312" is set to true during execution of T310 of a PSCell and triggers a measurement report for a measurement ID for which T312 is configured.

[0112] In addition, T312 may be stopped when an N311 continuous synchronization indication is received from the lower layer of the SpCell, when an RRCReconfiguration is received with reconfigurationWithSync for the cell group and a connection re-establishment procedure is initiated, when rlf-TimersAndConstant is reconfigured, when an MCG fault information procedure is initiated, and when T310 expires in the corresponding SpCell.

[0113] Timer T304 may be started upon reception of an RRCReconfiguration message containing reconfigurationWithSync or upon execution of a conditional reconfiguration, i.e., upon application of a stored RRCReconfiguration message containing reconfigurationWithSync, and may be stopped upon successful completion of random access in the corresponding SpCell.

[0114] N310 is specified in 3GPP TS38.331 related to RRC, and may be reset when an "In-sync" indication is received from a lower layer, when an RRC Reconfiguration using "reconfigurationWithSync" for the cell group (SCG) is received, or when a connection re-establishment procedure is initiated. N310 may also be incremented when an "out-of-sync" indication is received from a lower layer while timer T310 is stopped. When the maximum value of N310 is reached, timer T310 may be started.

[0115] The UE may predict a time instance called N310 consecutive Out-of-Sync and the probability that N310 consecutive Out-of-Sync will occur in a specific cell (which may be a serving cell or a neighboring cell including a candidate cell; the same applies below). The time instance may be read as a time point or a time stamp (the same applies below).

[0116] The UE may predict the interval from N310 consecutive Out-of-Sync to RLF occurrence in a specific cell. It may also predict the probability of RLF occurrence during this interval. The interval from N310 consecutive Out-of-Sync to RLF occurrence may be managed by T310 or a new timer (see Figures 7 and 8). The interval (start and end) may be represented as [t1, t2] or [t1, t1 + timer length]. The timer may be T310 or a new timer.

[0117] The UE may predict the time instance at which T310 / T312 or a new timer will start, and may predict the probability that the timer will start.

[0118] The UE may predict a time instance in which an RLF will occur. The UE may predict the probability of an RLF occurrence. Specifically, the UE may predict a time instance or a time window in which a random Access Problem (RACH failure) will occur. The UE may predict the probability of the time instance occurring. Furthermore, the UE may predict a time instance or a time window in which an rlc-MaxNumberRetransmission (excessive RLC retransmission) will occur. The UE may predict the probability of the time instance occurring.

[0119] The UE may predict a time instance or a time window in which a beamFailureRecoveryFailure will occur. The UE may predict the probability of the time instance occurring. The UE may also predict a time instance or a time window in which a Listen-Before-Talk (LBT) Failure will occur. The UE may predict the probability of the time instance occurring.

[0120] The UE may predict a time instance or a time window in which a BH (Backhaul)-RLFRecoveryFailure will occur, and may predict the probability of the time instance occurring.

[0121] The UE may predict a time instance when T310 / T312 or a new timer expires. The UE may predict the occurrence probability of the time instance. In the case of Handover failure (HOF) prediction using an AI / ML model, the UE may predict a time instance when T304 expires. The UE may predict the occurrence probability of the time instance.

[0122] The UE may predict a time instance at which T310 / T312 or a new timer will stop after starting. The UE may predict the probability of occurrence of the time instance. The UE may also predict a time instance at which N311 consecutive in-sync will occur after T310 / T312 or a new timer will start. The UE may predict the probability of occurrence of the time instance.

[0123] The UE may report the above-described prediction result to the network. Specifically, the prediction result may be reported periodically or in response to an event (event-based reporting). Event-based reporting may be performed when the RLF occurrence probability is equal to or greater than a predetermined threshold (e.g., 60%, 70%, 80%, 90%).

[0124] (3.5) Operation Example 2 In the following, the UE performs prediction regarding BF using an AI / ML model. Specifically, the UE may predict a time instance at which a beam failure instance indication is obtained from a lower layer in a specific cell. The UE may predict the occurrence probability of the time instance. Furthermore, the UE may predict a time instance at which a predetermined number of beam failure instance indications are obtained from a lower layer in a specific cell. The UE may predict the occurrence probability of the time instance.

[0125] The UE may predict a time instance at which a beam failure detection timer in a specific cell will start. The UE may predict the probability of occurrence of the time instance. The UE may also predict a time instance at which a beam failure detection timer in a specific cell will expire or stop. The UE may predict the probability of occurrence of the time instance.

[0126] The UE may predict a time instance in which BFI_COUNTER >= beamFailureInstanceMaxCount in a specific cell, and may predict the occurrence probability of the time instance.

[0127] The UE may predict a time instance at which beam failure recovery is triggered in a specific cell. The UE may predict the occurrence probability of the time instance. The UE may also predict a target beam index at which BF occurs. The beam index may be an SSB index or a CSI-RS index. The UE may predict the occurrence probability of the time instance.

[0128] (3.6) UE Capability A UE may report the presence or absence of the following capabilities (UE Capability Information) regarding RLF, BF, and HOF prediction using an AI / ML model to the network. The UE Capability Information may be defined for each UE, frequency range (FR), frequency channel (FC), etc. Furthermore, RRC signaling and configuration for reporting the UE Capability Information may be defined.

[0129] -Whether it is possible to predict a time instance called N310 consecutive Out-of-Sync in a specific cell and the probability that N310 consecutive Out-of-Sync will occur. -Whether it is possible to predict the interval from N310 consecutive Out-of-Sync to the occurrence of RLF in a specific cell, and whether it is possible to predict the probability that RLF will occur in that interval. -Whether it is possible to predict the time instance at which T310 or a new timer will start and the probability of that time instance occurring. -Whether it is possible to predict the time instance at which a randomAccessProblem (RACH failure) will occur and the probability of that time instance occurring. -Whether it is possible to predict the time instance at which an rlc-MaxNumberRetransmission (excessive RLC retransmissions) will occur and the probability of that time instance occurring. -Whether it is possible to predict the time instance at which a beamFailureRecoveryFailure will occur and the probability of that time instance occurring. -Whether it is possible to predict the occurrence probability of a time instance when T310 / T304 or a new timer expires and whether it is possible to predict the occurrence probability of that time instance. -Whether it is possible to predict the time instance when a specified number of beam failure instance indications are obtained from lower layers in a specific cell and whether it is possible to predict the occurrence probability of that time instance. -Whether it is possible to predict the time instance when beam failure recovery is triggered in a specific cell and whether it is possible to predict the occurrence probability of that time instance. -Whether it is possible to predict the beam index (SSB index or CSI-RS index) for which BF occurs and whether it is possible to predict the occurrence probability of that time instance. -AI / MLAccording to the above-described operational example, it is possible to narrow down the target (content) of specific prediction, such as the timing and probability of occurrence, of RLF / HOF / BF occurrence predicted by the AI / ML model. Specifically, the timing and probability of consecutive occurrences of out-of-sync of a wireless link, the timing and probability of acquiring a beam failure instance indication from a lower layer, and the like, can be predicted using the AI / ML model, and the prediction results can be utilized within the wireless communication system 10.

[0130] This will improve the accuracy of predicting the occurrence of RLF (HOF) and BF, and will enable effective improvement of UE and network performance using AI / ML models.

[0131] (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.

[0132] For example, in the above-described embodiment, an example has been described in which an AI / ML model is applied mainly to the occurrence of RLF and BF. However, as partially described in the above-described embodiment, prediction of occurrence timing, etc. using an AI / ML model may also be applied to the occurrence of RACH failure, LBT failure, etc.

[0133] Furthermore, in the above-described embodiment, operation examples 1 to 3 have been described, but only operations according to some of the operation examples may be applied.

[0134] 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.

[0135] Furthermore, specific, dedicated, UE-specific, and UE-dedicated may be interchangeable. Similarly, common, shared, group-common, UE-common, and UE-shared may be interchangeable.

[0136] In this disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0137] Furthermore, the block diagrams (FIGS. 2 and 3) used in the description of the above-described embodiments show functional blocks. These functional blocks (components) are realized by any combination of 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 software with the single device or multiple devices.

[0138] 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.

[0139] 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 9 is a diagram showing an example of the hardware configuration of the devices. As shown in Figure 9, the devices may be configured as a computer device 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.

[0140] 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.

[0141] Each functional block of the device (see FIGS. 2 and 3) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] 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).

[0149] 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).

[0150] 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.

[0151] 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.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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).

[0159] 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).

[0160] 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.

[0161] 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.

[0162] 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.

[0163] 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.

[0164] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0165] 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.

[0166] 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.

[0167] 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.

[0168] 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)).

[0169] 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.

[0170] 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.

[0171] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0172] 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.

[0173] 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 refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be a mobile object that moves autonomously based on an operational command. It 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 be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0174] 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).

[0175] 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.

[0176] 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.

[0177] 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.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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.

[0183] 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.

[0184] 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.

[0185] 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.

[0186] 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.

[0187] 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.

[0188] 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.

[0189] 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.

[0190] 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.

[0191] 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.

[0192] 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.

[0193] 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."

[0194] 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.

[0195] 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.

[0196] The reference signal may also be abbreviated as Reference Signal (RS) and may be called a pilot depending on the applicable standard.

[0197] 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."

[0198] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0199] 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.

[0200] 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.

[0201] 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.

[0202] 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.

[0203] 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."

[0204] 10 shows an example of the configuration of a vehicle 2001. As shown in Fig. 10, 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.

[0205] 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).

[0206] 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.

[0207] 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.

[0208] 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.

[0209] 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.

[0210] 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.

[0211] 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.

[0212] 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.

[0213] 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.

[0214] 10 Wireless communication system 20 NG-RAN 40 OAM / RIC 50 NF 100 gNB 110 Wireless communication unit 120 Handover processing unit 130 AI / ML model unit 140 Control unit 200 UE 210 Wireless communication unit 215 AI / ML model unit 220 Measurement processing 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 section 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 communication unit that performs wireless communication with a wireless base station via a wireless link; a control unit that uses a learning model to predict at least one of the timing and probability of consecutive occurrences of out-of-synchronization of the wireless link; and a transmission unit that transmits the prediction results by the control unit to a network.

2. The terminal according to claim 1, wherein the control unit predicts the time from the timing at which the out-of-synchronization occurs consecutively until it is determined that a failure has occurred in the wireless link.

3. A terminal comprising: a communication unit that performs wireless communication with a radio base station using an antenna beam; a control unit that uses a learning model to predict at least one of the timing at which a fault indication for the antenna beam will be obtained from a lower layer and the probability of obtaining the fault indication; and a transmission unit that transmits the prediction result by the control unit to the network.

4. The terminal according to claim 3, wherein the control unit predicts the timing at which a timer for detecting a fault in the antenna beam will be activated.

5. A wireless base station comprising: a communication unit that performs wireless communication with a terminal via a wireless link; and a control unit that uses a learning model to predict at least one of the timing and probability of consecutive occurrences of out-of-synchronization of the wireless link at the terminal.

6. A radio base station comprising: a communication unit that performs wireless communication with a terminal using an antenna beam; and a control unit that uses a learning model to predict at least one of the timing at which the terminal will obtain a fault indication for the antenna beam from a lower layer and the probability of obtaining the fault indication.

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