Terminal and communication method

Abstract

To allow a terminal to make a measurement report including a format and information elements suitable for mobility control using AIML in a wireless communication system.SOLUTION: A terminal includes a control unit that controls mobility from a serving cell to a candidate cell and determines whether a mobility event condition is met on the basis of the predicted quality of a reference signal of the candidate cell, and a transmission unit that, when the event condition is met, transmits a measurement report to a base station, the measurement report including information indicating the predicted quality of the reference signal.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a terminal and a communication method in a wireless communication system. [Background technology]

[0002] The 3GPP (registered trademark) (3rd Generation Partnership Project) is considering the application of artificial intelligence / machine learning (AIML) technology to wireless communication technology in the sixth generation mobile communication system (6G).

[0003] 3GPP is currently discussing a method of applying AIML to Conditional Lower-layer Triggered Mobility (LTM), which performs mobility (e.g., cell switching) based on measurement results in lower layers such as the physical layer or MAC layer. In LTM operation, a terminal performs Layer 1 (L1) measurements and reports the L1 measurement results to a base station. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 38.300 V18.5.0(2025-03) [Non-patent document 2] 3GPP TS 38.401 V18.5.0(2025-03) Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the operation of LTM with AIML, it is not clear what information elements should be included in the L1 measurement report sent from the terminal to the base station, and what format it should be in. As a result, the terminal may not be able to send information useful for mobility management to the base station, which could prevent efficient mobility management. [Means for solving the problem]

[0006] The terminal in this embodiment includes a control unit that controls mobility from a serving cell to a candidate cell and determines whether the mobility event conditions are met based on the predicted quality of the reference signal of the candidate cell, and a transmission unit that, when the event conditions are met, transmits a measurement report to a base station that includes information indicating the predicted quality of the reference signal. [Effects of the Invention]

[0007] According to this embodiment, it is possible for a terminal to make a measurement report including a format and information elements suitable for mobility control using AIML. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating an example of a wireless communication system according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram for explaining ETD (Event Time Difference). [Figure 3] FIG. 1 is a diagram illustrating a direct prediction method. [Figure 4] FIG. 2 is a sequence diagram showing an example of an operation procedure of the wireless communication system according to the present embodiment. [Figure 5] FIG. 2 is a sequence diagram showing an example of an operation procedure of the wireless communication system according to the present embodiment. [Figure 6] FIG. 2 is a sequence diagram showing an example of an operation procedure of the wireless communication system according to the present embodiment. [Figure 7]FIG. 10 is a diagram illustrating an example of a format of an L1 measurement report MAC CE in the first embodiment of the present invention. [Figure 8] FIG. 10 is a diagram illustrating an example of a format of an L1 measurement report MAC CE in Example 2 of the present embodiment. [Figure 9] FIG. 2 is a diagram illustrating an example of a functional configuration of a base station according to the present embodiment. [Figure 10] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal according to the present embodiment. [Figure 11] FIG. 2 is a diagram illustrating an example of a hardware configuration of a base station or a terminal according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present embodiment will be described below with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0010] In operation of the wireless communication system of this embodiment, existing technologies (e.g., LTE and NR (5G)) or future technologies (e.g., 6G) may be used as appropriate. The technologies used in the wireless communication system of this embodiment may not be limited to the above-mentioned LTE, NR, and 6G.

[0011] In the present embodiment described below, terms used in existing technologies, such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), PRACH (Physical random access channel), PDCCH (Physical Downlink Control Channel), PDSCH (Physical Downlink Shared Channel), PUCCH (Physical Uplink Control Channel), and PUSCH (Physical Uplink Shared Channel), are used. This is for convenience of description, and similar signals, functions, etc. may be called by other names. The above-mentioned terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even signals used in NR are not necessarily designated as "NR-".

[0012] In this embodiment, the duplex method may be a time division duplex (TDD) method, a frequency division duplex (FDD) method, or other methods (for example, flexible duplex, etc.).

[0013] In this embodiment, when radio parameters etc. are "configured," it may mean that a predetermined value is pre-configured, or that radio parameters notified from a base station or a terminal are set.

[0014] (System Configuration) Fig. 1 is a diagram for explaining a wireless communication system in this embodiment. As shown in Fig. 1, the wireless communication system in this embodiment includes a base station (gNB) 10 and a terminal (UE (User Equipment)) 20. Although Fig. 1 shows one base station 10 and one terminal 20, this is an example, and there may be a plurality of each.

[0015] The base station 10 is a communication device that provides one or more cells and performs wireless communication with the terminal 20. The physical resources of a wireless signal are defined in the time domain and the frequency domain, and the time domain may be defined by the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols, and the frequency domain may be defined by the number of subcarriers or the number of resource blocks. A TTI (Transmission Time Interval) in the time domain may be a slot, or a TTI may be a subframe.

[0016] The base station 10 transmits a synchronization signal and system information to the terminal 20. The synchronization signal is, for example, NR-PSS and NR-SSS. The system information is transmitted, for example, via the NR-PBCH and is also referred to as broadcast information. The synchronization signal and system information may be referred to as an SSB (SS / PBCH block). As shown in FIG. 1 , the base station 10 transmits control signals or data to the terminal 20 via DL (Downlink) and receives control signals or data from the terminal 20 via UL (Uplink). Both the base station 10 and the terminal 20 are capable of transmitting and receiving signals by performing beamforming. Both the base station 10 and the terminal 20 are capable of applying MIMO (Multiple Input Multiple Output) communication to DL or UL. Both the base station 10 and the terminal 20 may communicate via a secondary cell (SCell) and a primary cell (PCell) using Carrier Aggregation (CA). Furthermore, the terminal 20 may perform communication via a primary cell of the base station 10 and a primary secondary cell group cell (PSCell: Primary SCG Cell) of another base station 10 using DC (Dual Connectivity).

[0017] The terminal 20 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, or an M2M (Machine-to-Machine) communication module. As shown in FIG. 1 , the terminal 20 receives control signals or data from the base station 10 via DL and transmits control signals or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system. The terminal 20 receives various reference signals transmitted from the base station 10 and measures the propagation path quality based on the reception results of the reference signals. The terminal 20 may be referred to as a UE 20, and the base station 10 may be referred to as a gNB 10.

[0018] The wireless communication system in this embodiment supports LTM. LTM is a control method in a wireless communication system that causes the UE 20 to perform mobility-related operations, such as cell switching (handover) and beam switching (beam switching), based on measurement results or trigger conditions in a lower layer (such as the physical layer or MAC layer). LTM and conditional LTM described later are examples of mobility.

[0019] Compared with the control by the upper layer (such as the RRC layer), LTM can provide low-latency and rapid response, so it is particularly effective in improving mobility stability and throughput in high-mobility environments and high-density network environments.

[0020] The trigger in LTM is configured by conditions such as when a quality metric such as received power (RSRP) or signal-to-interference-plus-noise ratio (SINR) for a specific reference signal (CSI-RS, SSB, etc.) exceeds or falls below a predetermined threshold. These conditions are defined as LTM events (such as eventLTM2, eventLTM3, eventLTM4, eventLTM5) and are determined by the UE 20.

[0021] The execution of LTM may be performed based on settings from the network (such as gNB 10) or the UE 20 may execute it autonomously. By leveraging AIML technology, more advanced mobility management based on prediction becomes possible.

[0022] LTM events (eventLTM2, eventLTM3, eventLTM4, eventLTM5) are defined as follows.

[0023] <eventLTM2 (when the beam quality of the serving cell deteriorates below a predetermined threshold)> The UE 20 determines that the entry condition of eventLTM2 is satisfied when the following conditions are met, and determines that the leaving condition is satisfied when other conditions are met.

[0024] · Entering condition: Ms + Hys < Thresh · Leaving condition: Ms - Hys > Thresh Here, Ms is the measurement quantity of the beam of the serving cell measured based on the SS / PBCH block or CSI-RS, and it is a value without considering the offset. The beam corresponds to the RS set in the indicated TCI state or the RS having a QCL relationship with that RS.

[0025] Hys is the hysteresis parameter set for LTM event LTM2.

[0026] Thresh is the threshold parameter for the same event.

[0027] Ms is represented in dBm in the case of RSRP and in dB in the case of SINR, and Hys and Thresh are represented in dB units.

[0028] <eventLTM3 (when the beam of the candidate cell is of better quality than the beam of the serving cell)> UE 20 determines that the entering condition of eventLTM3 is satisfied when the following conditions are met, and the leaving condition is satisfied when another condition is met.

[0029] · Entering condition: Mn + Obn - Hys > Ms + Obs + Off · Leaving condition: Mn + Obn + Hys < Ms + Obs + Off Here, Mn is the measurement quantity of the beam of the LTM candidate cell measured based on the SS / PBCH block or CSI-RS, and the offset is not included.

[0030] Obn is the offset of the beam applied to the LTM candidate cell.

[0031] Ms is the measurement value of the current beam in the serving cell.

[0032] Obs is the offset with respect to the beam of the serving cell.

[0033] Off is the additional offset for eventLTM3.

[0034] Mn and Ms are expressed in dBm for RSRP and in dB for SINR, and all other values are expressed in dB units.

[0035] <eventLTM4 (when the beam of the candidate cell exceeds an absolute threshold)> UE 20 determines that the entry condition of eventLTM4 is satisfied when the following conditions are met, and the leaving condition is satisfied when another condition is met.

[0036] · Entry condition: Mn + Obn - Hys > Thresh · Leaving condition: Mn + Obn + Hys < Thresh Here, Mn is the beam measurement value of the LTM candidate cell, based on the SS / PBCH block or CSI-RS, without considering the offset.

[0037] Obn is the offset with respect to the beam of the LTM candidate cell.

[0038] Hys is the hysteresis parameter for the event.

[0039] Thresh is the absolute threshold set for eventLTM4.

[0040] Mn is expressed in dBm (for RSRP) or dB (for SINR), Obn and Hys are in dB units, and Thresh is expressed in the same unit as Mn.

[0041] <When the beam of the serving cell is worse than threshold 1 and the beam of the candidate cell is better than threshold 2)> UE 20 determines that the entry condition is satisfied when both of the following conditions are met, and determines that the leaving condition is satisfied when at least one of the conditions is met.

[0042] · Entry condition 1: Ms + Hys < Thresh1 · Entry condition 2: Mn + Obn - Hys > Thresh2 · Leaving condition 1: Ms - Hys > Thresh1 · Leaving condition 2: Mn + Obn + Hys < Thresh2 Here, Ms and Mn are the beam measurement quantities of the serving cell and the candidate cell, respectively, measured based on the SS / PBCH block or CSI-RS, and do not include offsets.

[0043] Obn is an offset for the beam of the candidate cell.

[0044] Hys is a hysteresis parameter for LTM5.

[0045] Thresh1 and Thresh2 are thresholds set for the serving cell and the candidate cell, respectively.

[0046] Ms and Mn are represented in dBm (RSRP) or dB (SINR), and the other parameters are represented in dB units.

[0047] In the wireless communication system of this embodiment, AIML technology is applied to the prediction of LTM events. As an evaluation index of the prediction accuracy by the AIML model, for example, the F1 score is used. The F1 score is defined by the following formula.

[0048] F1 score = 2 × Precision × Recall / (Precision + Recall) Here, precision is defined by the following formula:

[0049] Precision = n3 / (n1 + n3) Recall is defined by the following formula:

[0050] Recall = n3 / (n2 + n3) Here, n1, n2, and n3 are counters defined based on the results of event prediction. The definitions of these counters differ between the indirect prediction method and the direct prediction method.

[0051] In the indirect prediction method, it is defined as follows.

[0052] n3 (True Event Prediction): When the time difference (ETD: Event Time Difference) between the predicted event and the actual event is greater than or equal to 0 and less than or equal to a predetermined maximum ETD, or vice versa, the value of n3 is increased by 1.

[0053] n1 (false positive): If there are no actual events around the predicted event within the maximum ETD, the value of n1 is increased by 1.

[0054] · n2 (missed): If there are no predicted events within the maximum ETD around the actual event, the value of n2 is increased by 1.

[0055] ETD is the time difference between a predicted event and an event that actually occurred, as shown in Figure 2. If the ETD is less than or equal to the maximum ETD, it is not considered a false positive or a false negative, but is within the acceptable range. If the ETD is greater than the maximum ETD, the prediction is evaluated as both a false positive and a false negative.

[0056] On the other hand, in the direct prediction method, it is defined as follows.

[0057] · n3 (true event prediction): If there is a real event within the predicted event occurrence window with a probability exceeding a predefined threshold, the value of n3 is increased by 1.

[0058] n1 (false positive): If there is no actual event within the predicted event occurrence window with a probability exceeding the threshold, the value of n1 is increased by 1.

[0059] n2 (missed): If an actual event occurs but does not fall within any of the predicted event occurrence windows, the value of n2 is increased by 1.

[0060] In the direct prediction method, a predicted event is predicted based on a predetermined probability within an occurrence window from the current time t0 to a future time t1, as shown in FIG.

[0061] In this embodiment, the UE 20 predicts an event (e.g., an LTM event) using AIML, and transmits an L1 measurement report triggered by the predicted event (Predicted Event triggered L1 measurement report) to the gNB 10 using a MAC CE or an RRC message. In this embodiment, the L1 measurement report by the MAC CE is referred to as an L1 measurement report MAC CE.

[0062] In this embodiment, the beam and the reference signal may be interpreted interchangeably.

[0063] In this embodiment, the procedure in which the UE 20 predicts an LTM event (e.g., eventLTM2, eventLTM3, eventLTM4, or eventLTM5) using AIML and performs a report to the network based on the predicted result will be described with reference to Figures 4-6.

[0064] FIG. 4 is a sequence diagram showing an example of a processing flow for LTM event prediction and L1 measurement reporting using AIML.

[0065] In step S101, the gNB 10 transmits configuration information regarding LTM event prediction to the UE 20 (e.g., target event type, reporting threshold, occurrence time range, etc.).

[0066] In step S102, the UE 20 performs LTM event prediction using the AIML model based on the configuration information. The predicted LTM events include, for example, event LTM2 (the beam quality of the serving cell is lower than a predetermined threshold), event LTM3 (the beam quality of the candidate cell is better than that of the serving cell), event LTM4 (the beam of the candidate cell exceeds an absolute threshold), and event LTM5 (the serving cell is below threshold 1 and the candidate cell exceeds threshold 2).

[0067] Predicting an LTM event may be, for example, predicting whether an LTM event will occur at a predetermined time or time range in the future. The occurrence of an LTM event may mean, for example, satisfying an LTM event or satisfying an entering or leaving condition for an LTM event.

[0068] For example, the UE 20 may predict the quality of the reference signal of a candidate cell, and if the predicted reference signal quality meets a predetermined condition (e.g., an entering condition or a leaving condition of an LTM event), a measurement report may be triggered from the UE 20 to the gNB 10.

[0069] For example, the UE 20 may predict the quality of the reference signal of the serving cell and the quality of the reference signal of the candidate cell, and if the predicted quality of the reference signal of each of the serving cell and the candidate cell satisfies a predetermined condition (e.g., an entering condition or a leaving condition of an LTM event), a measurement report may be triggered from the UE 20 to the gNB 10.

[0070] In step S103, the UE 20 transmits an L1 measurement report triggered by the predicted LTM event to the gNB 10 using MAC CE.

[0071] Furthermore, the UE 20 may measure the radio quality (RSRP, RSRQ or SINR) of the serving cell and / or the candidate cell, and perform L1 measurement reporting when the measurement result satisfies an LTM event, i.e., the L1 measurement reporting may be triggered by the measured LTM event.

[0072] FIG. 5 is a sequence diagram showing an example of a processing flow related to LTM event prediction and L1 measurement reporting using AIML.

[0073] In step S111, the gNB 10 transmits configuration parameters for LTM event prediction to the UE 20.

[0074] In step S112, the UE 20 makes predictions based on the AIML model for the configured target LTM events.

[0075] In step S113, the UE 20 determines whether any of eventLTM2-eventLTM5 is satisfied or not according to the prediction result, and checks the report trigger condition (for example, the reliability of the prediction exceeds a predetermined threshold).

[0076] In step S114, the UE 20 transmits an L1 measurement report triggered by the predicted LTM event to the gNB 10 using MAC CE if the trigger condition is met.

[0077] FIG. 6 is a sequence diagram showing an example of a processing flow related to LTM event prediction and L1 measurement reporting using AIML.

[0078] In step S121, the gNB 10 transmits to the UE 20 configuration related to LTM event prediction (e.g., the F1 score threshold to be evaluated).

[0079] In step S122, the UE 20 executes an LTM event prediction process using AIML.

[0080] In step S123, the UE 20 predicts whether the predetermined eventLTM2-eventLTM5 conditions are met or not met.

[0081] In step S124, the UE 20 determines whether the F1 score or other reliability metric of the prediction exceeds a predetermined threshold.

[0082] In step S125, if it is determined that the prediction accuracy is sufficient, the UE 20 transmits an L1 measurement report triggered by the predicted LTM event to the gNB 10 using MAC CE.

[0083] An example of a report format for an L1 measurement report triggered by an LTM event predicted using AIML in this embodiment will be described below. The report format in this embodiment may be applied to an L1 measurement report triggered by a measured LTM event.

[0084] The reporting format of the L1 measurement report in the MAC CE or RRC message may include some or all of the following information elements:

[0085] (1) Report ID: This field indicates the corresponding predicted or measured measurement report ID associated with the L1 measurement report triggered by the predicted or measured event.

[0086] (2) Type: This field indicates the type of reference signal (RS) i of the LTM candidate cell that is included in the L1 measurement report triggered by a predicted or measured event.

[0087] (a) Field value "00" indicates the predicted or measured quality of the RS (or beam) that meets the entry conditions regarding the TTT (Time to Trigger) of the event associated with the report ID and triggered this measurement report MAC CE.

[0088] (b) Field value “01” indicates the predicted or measured quality of the RS (or beam) that met the leaving condition for the TTT of the event associated with the report ID and triggered this measurement report MAC CE.

[0089] (c) A field value of “10” indicates the predicted or measured quality of an RS in the BEAM_TRIGGERED_LIST associated with the report ID, other than an RS (or beam) whose type is set to “00”, as specified in, for example, the 3GPP technical specifications.

[0090] (d) Field value "11" indicates the predicted or measured quality of RSs that do not satisfy the TTT-related event when configured by the network, for example, by allowReportAnyPredictedBeam as specified in TS 38.331. The predicted or measured quality of RSs that do not satisfy the TTT-related event is selected based on descending order of measured or predicted quality.

[0091] (3) RSRI (Reference Signal Resource Index): This field indicates the reference signal resource index (i.e., SS / PBCH Block Resource Indicator (SSBRI) or CSI-RS Resource Indicator (CRI)) of beam i of the LTM candidate cell for L1 measurement reports triggered by predicted or measured events.

[0092] (4) Predicted RSRP (Reference Signal Received Power) and predicted RSRP time info (e.g., timestamp): Indicates the predicted reference signal received power (RSRP) for the beam of the LTM candidate cell and its predicted time.

[0093] (5) Measured RSRP: Indicates the measured RSRP for the beam of the LTM candidate cell.

[0094] (6) Predicted DIFFRSRP and Predicted DIFFRSRP time information (e.g., timestamp): Indicates the predicted RSRP difference between the beams of the serving cell and the LTM candidate cell and its predicted time. DIFFRSRP may mean differential RSRP.

[0095] (7) Measured DIFFRSRP: Indicates the measured RSRP difference between the beams of the serving cell and the LTM candidate cell.

[0096] (8) Predicted RSRP of serving (current) beam or serving (current) cell and its time stamp: Indicates the predicted RSRP of the serving beam or serving cell and its predicted time.

[0097] (9) Measured RSRP of serving (current) beam or serving (current) cell: Indicates the measured RSRP of the serving beam or serving cell.

[0098] By including these information elements, the UE 20 can report more detailed and diverse L1 measurement information to the gNB 10 based on the results of predicting LTM events using AIML. The gNB 10 can utilize this reported information to perform more appropriate handover control and resource management.

[0099] An example of the format of an L1 measurement report MAC CE triggered by a predicted or measured event will be described below with reference to FIGS.

[0100] Example 1 7 is a diagram illustrating an example of a format of an L1 measurement report MAC CE in Example 1 of the present embodiment. The format in Example 1 may include a field for an L1 measurement report triggered by a measured event in addition to a field for an L1 measurement report triggered by a predicted event. In Example 1, the L1 measurement report MAC CE transmitted from the UE 20 to the gNB 10 may be configured in any of the following formats:

[0101] (Format 1-1) L1 measurement report format triggered by predicted or measured events (variable length) (Format 1-2) Predicted or measured truncated event triggered L1 measurement report format (variable length) The truncated L1 measurement report format is, for example, a format in which some information elements included in the normal L1 measurement report format (a) are omitted or the size is shortened.

[0102] The L1 measurement report format triggered by a predicted or measured event is identified by a MAC subheader with an extended Logical Channel ID (eLCID) as specified, for example, in Table 6.2.1-1b of 3GPP TS 38.321. Table 6.2.1-1b shows values ​​of one-octet eLCID for DL-SCH, and provides a table mapping LCID values ​​with corresponding codepoints and indices.

[0103] The truncated L1 measurement report MAC CE includes at least one triggered reference signal (RS) having at least a report ID field and a corresponding measured quantity. The measured quantity indicates a quantified indicator (e.g., RSRP, RSRQ, SINR value) obtained by measurement. In this embodiment, the measured (predicted) quality may be used interchangeably with the measured (predicted) quantity.

[0104] As shown in FIG. 7, the fields included in the L1 measurement report MAC CE in the first embodiment are defined as follows:

[0105] (1-1) Report ID: This field indicates the corresponding predicted or measured measurement report ID associated with the L1 measurement report triggered by the predicted or measured event. The length of the Report ID field is 6 bits.

[0106] (1-2) Type i: This field indicates the type of reference signal (RS) i of the LTM candidate cell that is included in the L1 measurement report triggered by the predicted event. The length of the field is 2 bits.

[0107] (a) A field value of "00" indicates the predicted quality or measured quality of the RS that satisfies the entry condition regarding the TTT (Time to Trigger) of the event associated with the report ID and triggered this measurement report MAC CE.

[0108] (b) A field value of "01" indicates the predicted or measured quality of the RS that met the leaving condition for the TTT of the event associated with the report ID and triggered this measurement report MAC CE.

[0109] (c) A field value of "10" indicates the predicted or measured quality of RSs in the BEAM_TRIGGERED_LIST associated with the report ID, other than RSs whose type is set to "00", as specified in, for example, the 3GPP technical specifications.

[0110] (d) A field value of "11" indicates the predicted or measured quality of an RS that does not satisfy a TTT-related event when configured by the network, for example, by allowReportAnyPredictedBeam as specified in 3GPP TS 38.331. The predicted or measured quality of an RS that does not satisfy a TTT-related event is selected based on descending order of the measured or predicted quantity.

[0111] (1-3) RSRIi: This field indicates the reference signal resource index (i.e., SS / PBCH Block Resource Indicator (SSBRI) or CSI-RS Resource Indicator (CRI)) of beam i of the LTM candidate cell for L1 measurement reports triggered by predicted or measured events. The maximum number of non-serving RSs reported is set by maxNumberOfReportedBeams. The first RS is the RS with the highest predicted or measured quality in this predicted measurement report MAC CE. The length of the RSRI index field is 9 bits.

[0112] (1-4) Predicted RSRP1: This field indicates the predicted RSRP (i.e., L1-RSRP) of the first beam based on the SS / PBCH block or CSI-RS, as specified in 3GPP TS 38.215, for example. The length of the RSRP1 field is 7 bits. The RSRP is the power level of the reference signal (e.g., the SS / PBCH block or the CSI-RS) received by the UE 20, and is an example of an indicator of radio quality.

[0113] (1-5) Measured RSRP1: This field indicates the measured quality of the first beam based on the SS / PBCH block or CSI-RS (i.e., L1-RSRP), for example, as specified in 3GPP TS 38.215. The length of the RSRP1 field is 7 bits.

[0114] (1-6) Predicted DiffRSRPi: This field indicates the difference between the measured quality of the first referenced beam and the predicted quality derived for beam i of the LTM candidate cell based on the SS / PBCH block or CSI-RS. The length of the DiffRSRPi field is 4 bits. The quality may be calculated based on the specifications in 3GPP TS 38.215, for example.

[0115] (1-7) Measured DiffRSRPi: This field indicates the difference between the measured quality of the first beam referenced and the measured quality derived for beam i of the LTM candidate cell based on the SS / PBCH block or CSI-RS. The length of the DiffRSRPi field is 4 bits.

[0116] (1-8) Predicted Serving RSRP (Predicted RSRP serving): This field indicates the predicted quality (i.e., L1-RSRP) based on the SS / PBCH block or CSI-RS for the current RS of the serving cell, if the UE is configured to report predicted measurement results of the current RS of the serving cell by reportCurrentBeam. The length of the RSRP serving field is 7 bits.

[0117] (1-9) Measured RSRP (Measured RSRP serving): This field indicates the quality (i.e., L1-RSRP) measured based on the SS / PBCH block or CSI-RS for the current RS of the serving cell when the UE is configured to report the measurement result of the current RS of the serving cell by reportCurrentBeam. The length of the RSRP serving field is 7 bits.

[0118] (1-10) R: Reserved bit, set to "0".

[0119] Example 2 8 is a diagram illustrating an example of a format of an L1 measurement report MAC CE in Example 2 of the present embodiment. The format in Example 2 is a format specialized mainly for fields related to predicted measurement values. The L1 measurement report MAC CE in Example 2 may be configured in any of the following formats:

[0120] (Format 2-1) L1 measurement report format triggered by predicted events (variable length) (Format 2-2) Predicted truncated event triggered L1 measurement report format (variable length) The L1 measurement report format triggered by the predicted event is identified by a MAC subheader with an eLCID as specified, for example, in Table 6.2.1-1b of 3GPP TS 38.321 mentioned above.

[0121] The truncated L1 measurement report MAC CE includes at least one triggered reference signal (RS) with a report ID field and a corresponding predicted measurement quantity.

[0122] As shown in FIG. 8, the fields included in the L1 measurement report MAC CE in the second embodiment are defined as follows:

[0123] (2-1) Report ID: This field indicates the corresponding predicted measurement report ID associated with the L1 measurement report triggered by the predicted event. The length of the Report ID field is 6 bits.

[0124] (2-2) Type i: This field indicates the type of reference signal (RS) i of the LTM candidate cell that is included in the L1 measurement report triggered by the predicted event. The length of the field is 2 bits.

[0125] (a) A field value of "00" indicates the predicted quality of the RS that met the entry condition for the TTT of the event associated with the report ID and triggered this measurement report MAC CE.

[0126] (b) A field value of "01" indicates the predicted quality of the RS that met the leaving condition for the TTT of the event associated with the report ID and triggered this measurement report MAC CE.

[0127] (c) A field value of "10" indicates the predicted quality of RSs in the BEAM_TRIGGERED_LIST associated with the report ID, other than RSs with type set to "00", as specified in, for example, the 3GPP technical specifications.

[0128] (d) Field value “11” indicates the predicted quality of RSs that do not satisfy the TTT-related event when set by the network, for example, by allowReportAnyPredictedBeam as specified in 3GPP TS 38.331. The predicted quality of RSs that do not satisfy the TTT-related event is selected based on descending order of predicted quality.

[0129] (2-3) RSRIi: This field indicates the reference signal resource index (i.e., SS / PBCH Block Resource Indicator (SSBRI) or CSI-RS Resource Indicator (CRI)) of beam i of the LTM candidate cell for the L1 measurement report triggered by the predicted event. The maximum number of non-serving RSs reported is set by maxNumberOfReportedBeams. The first RS is the RS with the highest predicted quality in this predicted measurement report MAC CE. The length of the RSRI index field is 9 bits.

[0130] (2-4) Predicted RSRP1: This field indicates, for example, the predicted quality of the first beam based on the SS / PBCH block or CSI-RS (i.e., L1-RSRP). The length of the RSRP1 field is 7 bits.

[0131] (2-5) Predicted DiffRSRPi: This field indicates the difference between the (predicted or measured) quality of the initial beam and the predicted quality derived for beam i of the LTM candidate cell based on the SS / PBCH block or CSI-RS. The length of the DiffRSRPi field is 4 bits.

[0132] (2-6) Predicted Serving RSRP (Predicted RSRP serving): This field indicates the predicted quality (i.e., L1-RSRP) based on the SS / PBCH block or CSI-RS for the current RS of the serving cell, if the UE is configured to report the predicted or measurement results of the current RS of the serving cell by reportCurrentBeam. The length of the RSRP serving field is 7 bits.

[0133] (2-7) R: A reserved bit that is set to "0."

[0134] The field configuration of the MAC CE shown in the above-mentioned first and second embodiments is an example, and fields may be added, deleted, their order changed, or their bit length changed, without departing from the spirit of the present invention.

[0135] According to the above-described embodiment, it is possible to clarify the format and information elements for L1 measurement reports triggered by predicted LTM events using AIML, thereby enabling the UE 20 to perform measurement reports with formats and information elements suitable for mobility control using AIML.

[0136] (Device configuration) Next, a description will be given of an example of the functional configuration of the base station (gNB) 10 and the terminal (UE) 20 that execute the processes and operations described above. The base station 10 and the terminal 20 include functions for executing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions in the embodiments.

[0137] <Base station (gNB)> Fig. 9 is a diagram showing an example of the functional configuration of the base station 10 in this embodiment. As shown in Fig. 9, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Fig. 9 is merely an example. As long as the operations in this embodiment can be performed, the names of the functional divisions and functional units may be any. The transmitting unit 110 and the receiving unit 120 may be collectively referred to as a communication unit.

[0138] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The transmitter 110 transmits setting information, instructions, notifications, etc. related to a low-power wake-up signal to the terminal 20. The transmitter 110 transmits notifications related to switching of monitoring operations to the terminal. The receiver 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of higher layers from the received signals. The transmitter 110 has a function of transmitting PSS, SSS, PBCH, DL / UL control signals, etc. to the terminal 20. The receiver 120 receives inter-network node messages from other network nodes.

[0139] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20. The content of the setting information is, for example, information on the operations explained in the embodiments.

[0140] The control unit 140 controls the settings, instructions, and notifications related to the operations described in the embodiments. The function unit related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and the function unit related to signal reception in the control unit 140 may be included in the receiving unit 120.

[0141] <Device (UE)> Fig. 10 is a diagram showing an example of the functional configuration of the terminal 20 in this embodiment. As shown in Fig. 10, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Fig. 10 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations in this embodiment. The transmitting unit 210 and the receiving unit 220 may be collectively referred to as a communication unit.

[0142] The transmitter 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The transmitter 210 transmits capability information in a low-power wake-up signal to the base station 10. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals. The receiver 220 has a function of receiving PSS, SSS, PBCH, DL / UL / SL control signals, etc. transmitted from the base station 10. The receiver 220 receives paging notification information and configuration information, instructions, and notifications related to the low-power wake-up signal from the base station 10. For example, the receiver 220 receives a low-power wake-up signal from the base station 10. The configuration unit 230 stores various configuration information received from the base station 10 by the receiver 220. The configuration unit 230 also stores pre-configured configuration information. The configuration information includes, for example, information on the operations described in the embodiments.

[0143] As described in the embodiments, the control unit 240 controls settings, instructions, and notifications related to the operations described in the embodiments. A functional unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and a functional unit related to signal reception in the control unit 240 may be included in the receiving unit 220.

[0144] (Hardware configuration) The block diagrams (FIGS. 9 and 10) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by hardware, software, or a combination of these. The method of realizing each functional block is not particularly limited. That is, each functional block may be realized by using one device that is physically or logically coupled, or may be realized by using two or more devices that are physically or logically separated and connected directly or indirectly (for example, using wires, wirelessly, etc.). The functional block may be realized by combining software with the one device or the multiple devices.

[0145] For example, a base station, a terminal, a network node, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 11 is a diagram illustrating an example of the hardware configuration of a base station and a terminal according to an embodiment of the present disclosure. The above-described base station 10 and terminal 20 may be physically 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.

[0146] In the present disclosure, the term "apparatus" may be interchangeable with any two terms selected from a set of terms such as circuit, device, unit, module, chip, means, etc. The hardware configurations of the base station 10 and the terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0147] Each function in the base station 10 and the terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001, memory 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls the reading, writing, or both reading and writing of data in the memory 1002 and storage 1003.

[0148] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, a baseband signal processing unit, a call processing unit, etc. may be realized by the processor 1001. Although only one processor 1001 is shown in the figure, there may be multiple processors.

[0149] The processor 1001 reads programs (program codes), software modules, data, etc. from the storage 1003, the communication device 1004, or both the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 401 of the terminal 20 may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and similar implementations may be made for other functional blocks. While the above-described various processes have been described as being executed by a single processor 1001, they may also 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, or may be provided to the computer via the communication device 1004, for example.

[0150] The present disclosure also provides a computer program product including a computer program, which may implement the steps of the methods described in the above embodiments when the computer program is executed by a computer (e.g., the processor 1001).

[0151] The memory 1002 is a computer-readable recording medium and may be configured, for example, as a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), or a combination of at least two of these. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), or the like. The memory 1002 can store executable programs (program codes), software modules, and the like for executing the wireless communication method according to one embodiment of the present disclosure.

[0152] Storage 1003 is a computer-readable recording medium, and may be, for example, an optical disk such as a CD-ROM (Compact Disc 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, or a combination of at least two of these. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, memory 1002, storage 1003, or a database, server, or other appropriate medium including both memory 1002 and storage 1003.

[0153] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via a wired network, a wireless network, or both wired and wireless networks, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, or a combination of at least two of these. For example, a transmitting / receiving antenna, an amplifier unit, a transmitting / receiving unit, or a transmission path interface may be realized by the communication device 1004. The transmitting / receiving unit may be implemented as a transmitting unit and a receiving unit that are physically or logically separated.

[0154] The input device 1005 is an input device that receives input from the outside (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, or a combination of at least two of these). The output device 1006 is an output device that performs output to the outside (for example, a display, a speaker, an LED lamp, or a combination of at least two of these). The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0155] The processor 1001, memory 1002, and other devices are connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between the devices.

[0156] The base station 10 and the terminal 20 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), a field programmable gate array (FPGA), a graphics processing unit (GPU), a neural processing unit (NPU), or a combination of at least two of these, 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.

[0157] <Additional notes> (Additional note 1) a control unit that controls mobility from a serving cell to a candidate cell, and determines whether a condition for the mobility event is met based on the predicted quality of a reference signal of the candidate cell; A terminal comprising: a transmitter that transmits, when the event condition is satisfied, a measurement report including information indicating the predicted quality of the reference signal to a base station.

[0158] (Additional note 2) The event condition is an entering condition or a leaving condition, The terminal of claim 1, wherein the measurement report further indicates that the entering condition has been met or that the leaving condition has been met.

[0159] (Additional note 3) A terminal as described in Supplementary claim 1, wherein the measurement report further includes information indicating the difference between the measured quality of a first beam and the predicted quality of a second beam of the candidate cell based on a reference signal of the candidate cell.

[0160] (Additional note 4) The control unit predicts quality of a reference signal of the serving cell; The terminal according to Supplementary Note 1, wherein the measurement report further includes information indicating the predicted quality of the reference signal of the serving cell.

[0161] (Additional note 5) The mobility is LTM (Lower layer Triggered Mobility), The terminal according to Supplementary Item 1, wherein the control unit predicts the quality of the reference signal of the candidate cell using an AIML (Artificial Intelligence / Machine Learning) model.

[0162] (Additional note 6) A communication method performed by a terminal, comprising: controlling mobility from a serving cell to a candidate cell, and determining whether a condition for the mobility event is met based on a predicted reference signal quality of the candidate cell; When the event condition is satisfied, transmitting a measurement report to a base station, the measurement report including information indicating the predicted reference signal quality.

[0163] According to the configuration described in the supplementary paragraph, it is possible for a terminal to make a measurement report including a format and information elements suitable for mobility control based on predictions using AIML.

[0164] (Supplementary explanation of the embodiment) Although the present embodiment has been described above, the disclosed invention is not limited to such an embodiment, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be used in combination as needed, and matters described in one item may apply to matters described in another item (unless inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of the processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams. However, such devices may be implemented using hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to this embodiment and the software operated by the processor of the terminal 20 according to this embodiment may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

[0165] The aspects / embodiments described in the present disclosure may be categorized as Long Term Evolution (LTE), LTE-Advanced (LTE-A), International Mobile Telecommunications-Advanced (IMT-Advanced), 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 5G-Advanced (5G-A), 6th generation mobile communication system (6G), xth generation mobile communication system (x is, for example, an integer or a decimal number)), Future Radio Access (FRA), New Radio (NR), New radio access (NX), Future generation radio access (FX), Open Radio Access Network (O-RAN), Wideband Code Division Multiple Access (W-CDMA) (registered trademark), Global System for Mobile communications (GSM) (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) Engineers) 802.11, IEEE802.11x (where x is any character string such as b, a, g, n, ac, ax, be, or bn, and when x=n it is called Wi-Fi4, when x=ac it is called Wi-Fi5, when x=ax it is called Wi-Fi6 or Wi-Fi6E, when x=be it is Wi-Fi7, and when x=bn it is called Wi-Fi8, etc. Wi-Fi is a registered trademark.), IEEE802.16 (WiMAX (registered trademark), IEEE802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), network virtualization technology (e.g., NFV (Network Function Virtualization), SFC (Service Function Chaining), SDN (Software Defined Networking)), or LPWA (Low Power Wide Area). Each aspect / embodiment described in the present disclosure may be applied to a system based on a combination of at least two of these technologies. Of course, "based on" may refer not only to a system that uses the technology, but also to a system that uses an extension or modification of the technology.

[0166] In the present disclosure, any two terms selected from a set of terms such as "base station (BS)", "radio base station", "fixed station (fixed station)", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point (AP)", "transmission point (TP)", "reception point (RP)", "transmission / reception point (TRP)", "radio unit (RU)", "remote unit (RU)", "control unit (CU)", "distributed unit (DU)", "remote radio head (RRH)", "node", "gateway", "terrestrial base station", "stratospheric base station", "unmanned aerial vehicle", "high altitude platform station (HAPS)", "airborne platform", "panel", "cell", "radio access network (RAN)", and "network" may be used interchangeably.

[0167] Each cell accommodated by a base station may be referred to by terms such as a macro cell, a small cell, a femto cell, a pico cell, a serving cell, or a super cell. In the present disclosure, any two terms selected from a set of terms such as "cell," "sector," "cell group," "carrier," "component carrier," "cluster," "bandwidth part (BWP)," and "carrier bandwidth" may be used interchangeably.

[0168] In the present disclosure, any two terms selected from the set of terms such as "Mobile Station (MS)", "user terminal", "User Equipment (UE 20)", "Device", "Module" and "Terminal" may be used interchangeably.

[0169] A terminal may be referred to 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, router (e.g., home router, mobile router, etc.), TCU (Telematics Control Unit), or some other suitable terminology.

[0170] The base station and the terminal may each be composed of one or more devices. The devices constituting at least a portion of the base station and the terminal may be called a transmitting device, a receiving device, a communication device, etc. Note that the devices constituting at least a portion of the base station and the terminal may be, for example, an object itself, such as a vehicle, a transport vehicle, an automobile, a motorcycle, a bicycle, a connected car, an excavator, a bulldozer, a wheel loader, a dump truck, a forklift, a train, a bus, a handcar, a rickshaw, a ship and other watercraft, an airplane, a rocket, an unmanned aerial vehicle, a stratospheric base station (e.g., a High Altitude Platform Station (HAPS)), an artificial satellite (e.g., a Low Earth Orbit (LEO) satellite, a Medium Earth Orbit (MEO) satellite, a Geostationary Earth Orbit (GEO) satellite), a drone (registered trademark), a multicopter, a quadcopter, a balloon, or an Internet of Things (IoT) device (e.g., a smart meter, a sensor), or may include, but are not limited to, an object or device mounted on the object. The object may be a moving object (hereinafter referred to as a "moving object"; this does not exclude the case where the moving object is in a stationary state where it is not moving), or may be a fixedly positioned object (hereinafter referred to as a "non-moving object").

[0171] A base station in the present disclosure may be read as a terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a terminal is replaced with communication between multiple terminals (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)) or communication of a non-terrestrial network (NTN). In this case, the terminal 20 may be configured to have at least some of the functions of the base station 10 described above. Terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "sidelink") or terms corresponding to NTN (for example, feeder link or service link). For example, an uplink channel or a downlink channel may be read as a sidelink channel.

[0172] The present disclosure is also applicable to cases where at least some of the devices constituting the base station and the terminal operate outside the ground (for example, in the atmosphere or outer space).

[0173] In this disclosure, the term "terminal" may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the terminal 20 described above.

[0174] 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) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB))), other signals, or a combination of at least two of these. Note that the physical layer signaling may be referred to as Layer 1 (L1) control information. The MAC signaling may be referred to as a MAC Control Element (CE) or a MAC Protocol Data Unit (PDU), for example. The RRC signaling may be referred to as an RRC message or an information element (IE) in the RRC message. The RRC message may be, for example, a message used for controlling an RRC connection (for example, setup, reconfiguration, establishment, reestablishment, release, or resume), mobility, a measurement report, or notification of a terminal's capabilities, or may be an information element within the message. Notification of information may be explicit or implicit. Note that explicit notification of certain information means notification of the certain information itself, and implicit notification of certain information may mean notification of information other than the certain information, or may mean that the certain information is considered to have been notified when a certain condition is satisfied.Notification of information may include not only notification between the same layers of different devices (e.g., between a lower layer or an upper layer of the base station 10 and the terminal 20) but also notification between different layers in the same or different devices (e.g., between a lower layer and an upper layer in the base station 10 or the terminal 20). Notification of information from one device to another device may be performed via one or more devices. With regard to any information (e.g., a variable, a constant, a parameter, a setting) described in the present disclosure, even if not specifically specified in the above embodiments, information indicating / specifying (or related to) the any information (value) may be notified from any first device (e.g., a terminal / base station) to any second device (e.g., a base station / terminal).

[0175] 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.

[0176] In the present disclosure, a specific operation described as being performed by a base station may be performed by its upper node or by some of its upper nodes (e.g., CU, RU, or DU, etc.) in some cases. It is clear that various operations performed for communication with a terminal in a RAN or core network may be performed by at least some of the base station and other network nodes other than the base station. The other network node may be one node or a combination of multiple nodes. The network node is, for example, a node provided in various core networks such as EPC (Evolved Packet Core) and 5GC (5G Core Network), and provides one or more network functions (NF: Network Functions), but is not limited to this.

[0177] In the present disclosure, the action of "a terminal receives information from a base station" accompanies the action of "the base station transmits the information to the terminal", "the base station generates the information", or both. Similarly, the action of "a terminal transmits information to a base station" accompanies the action of "the base station receives the information from the terminal". The actions of "the terminal is configured to..." or "configure UE 20 to..." may include the action of "the base station transmits configuration information regarding the configuration of the terminal" and the action of "the terminal configures a predetermined operation based on the configuration information".

[0178] Each aspect / embodiment described in the present disclosure may be used alone, in combination, or switched depending on the implementation.

[0179] The present disclosure has been described above, but it is for illustrative purposes only, and the present invention is not limited to the aspects / embodiments described in the present disclosure. The present disclosure can be implemented in modified and altered forms without departing from the spirit of the invention. The present disclosure and its modifications and alterations are included in the scope of the present invention and its equivalents.

[0180] 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 or that the first element must in some way precede the second element.

[0181] The radio resource may be defined by a combination of resource units in one or more domains, such as the time domain, the frequency domain, the spatial domain, the code domain, and the power domain.

[0182] For example, resources in the time domain may be defined by one or more time units. The one or more time units may include, but are not limited to, a radio frame, a subframe, a slot, a symbol, a transmission time interval (TTI), or a combination of at least two of these. The time unit may be a fixed-length time unit independent of numerology, a variable-length time unit dependent on numerology, or both. Examples of fixed-length time units include, but are not limited to, a subframe consisting of one or more slots and a radio frame including multiple subframes. Examples of variable-length time units include, but are not limited to, a symbol and a slot including a fixed number of symbols. Note that a certain time unit may be divided into time units shorter than the certain time unit. Examples of shorter time units include, but are not limited to, a minislot consisting of fewer symbols than the number of symbols constituting a slot. The above-described time units may include, for example, time units used as units for scheduling, link adaptation, etc. Any time unit in the present disclosure may be read as another time unit.

[0183] Numerology is a parameter that defines the physical layer structure, and may be a parameter based on at least one of subcarrier spacing (SCS), symbol length, cyclic prefix length, and sampling time, for example.

[0184] Resources in the frequency domain may be defined, for example, by one or more frequency units. The one or more frequency units may include, for example, subcarriers, resource blocks (RBs), bandwidth parts (BWPs), carrier bandwidths, or a combination of at least two of these, but the terminology of the frequency units is not limited to these. The number of subcarriers included in a frequency unit may be a fixed number regardless of numerology, or may be a variable number that changes depending on numerology. For example, an RB is composed of a predetermined number of consecutive subcarriers in the frequency domain, and the number of subcarriers included in the RB may be the same regardless of numerology, for example, 12, but is not limited to this. A BWP may be composed, for example, of one or more consecutive RBs within a certain carrier bandwidth, but is not limited to this. One or more BWPs may be configured within one carrier for terminal 20, and at least one of the BWPs may be activated. Any frequency unit in the present disclosure may be interchangeable with another frequency unit.

[0185] Resources in both the time domain and the frequency domain may be defined by one or more time / frequency units, each of which is composed of a time unit and a frequency unit, such as, but not limited to, a resource element (RE) composed of one symbol and one subcarrier, a resource element group (REG) composed of a predetermined number of REs, or a control resource set (CORESET) composed of a predetermined number of symbols and a predetermined number of RBs.

[0186] The resources in the spatial domain may be defined, for example, by one or more spatial units, including, but not limited to, a beam, a layer of a multi-input multi-output (MIMO), an antenna port, or a combination of at least two of these.

[0187] The resources in the code domain may be defined by one or more code units, such as, but not limited to, a cyclic shift (CS), an orthogonal cover code (OCC), or a combination thereof.

[0188] 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.

[0189] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc. [Explanation of symbols]

[0190] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 terminals 210 Transmitter 220 Receiving unit 230 Setting Section 240 Control Unit 1001 processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication equipment 1005 Input Device 1006 Output Device

Claims

1. a control unit that controls mobility from a serving cell to a candidate cell, and determines whether a condition for the mobility event is met based on the predicted quality of a reference signal of the candidate cell; A terminal comprising: a transmitter that transmits, when the event condition is satisfied, a measurement report including information indicating the predicted quality of the reference signal to a base station.

2. The event condition is an entering condition or a leaving condition, The terminal of claim 1 , wherein the measurement report further indicates that the entering condition is met or that the leaving condition is met.

3. The terminal of claim 1 , wherein the measurement report further includes information indicating a difference between a measured quality of a first beam and a predicted quality of a second beam of the candidate cell based on a reference signal of the candidate cell.

4. The control unit predicts quality of a reference signal of the serving cell; The terminal according to claim 1 , wherein the measurement report further includes information indicating a quality of the predicted reference signal of the serving cell.

5. The mobility is LTM (Lower layer Triggered Mobility), The terminal according to claim 1 , wherein the control unit predicts the quality of the reference signal of the candidate cell using an AIML (Artificial Intelligence / Machine Learning) model.

6. A communication method performed by a terminal, comprising: controlling mobility from a serving cell to a candidate cell, and determining whether a condition for the mobility event is met based on a predicted reference signal quality of the candidate cell; When the event condition is satisfied, transmitting a measurement report to a base station, the measurement report including information indicating the predicted reference signal quality.

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