Terminal

Abstract

A terminal comprising: a control unit that calculates, using a learning model, a predicted value of a transmission timing, at which data is to be transmitted to a transition destination base station and which is used to connect to the base station without performing random access, and an effective period of the transmission timing; and a transmission unit that transmits the predicted value and the effective period to the base station.

Description

Terminal

[0001] The present disclosure relates to a terminal that performs mobility-related operations using a learning model.

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

[0003] For example, the use of artificial intelligence / machine learning (AI / ML) models (hereinafter also referred to as learning models) is being considered. The learning models are installed in terminals (hereinafter also referred to as user equipment (UE)) or base stations (hereinafter also referred to as gNodeB (gNB)) and are used to predict various parameters. By using the various parameters predicted by the learning models, performance improvements are expected in various areas, such as Channel State Information (CSI) feedback, beam management (BM), positioning, mobility, network slicing, and Quality of Experience (QoE) (Non-Patent Document 1).

[0004] One type of the mobility mentioned above is RACH-less HO, which realizes quick handover (HO) by omitting the Random Access (RA) procedure. RACH-less HO is, for example, RACH-less Lower layer Triggered Mobility (LTM), which is currently being discussed, but it may also be RACH-less Conditional HO (CHO), which is scheduled for future discussion.

[0005] RACH-less HO includes a procedure called the early sync procedure as a preliminary step to achieve rapid HO. The early sync procedure is a procedure for the UE to obtain a Timing Advance (TA) value between the UE and the gNB. The TA value is a parameter that advances the transmission timing at which the UE transmits data and indicates the transmission timing for each UE. The early sync procedure allows the UE to obtain the TA value in advance, so the RA procedure during HO can be omitted.

[0006] “Moderator's summary for REL-19 RAN2 topic AI / ML for Air Interface SI (Mobility)”, RP-232622, 3GPP TSG RAN Meeting #101, 3GPP, September 11-15, 2023

[0007] However, in the early sync procedure, many processes must be performed between the source gNB and target gNB (or between the source DU and target DU in the case of inter-DU HO), before the UE can obtain the TA value, which takes a long time. For example, in the case of inter-DU HO, the following processes are required: - The source DU instructs the UE to send a PDCCH-ordered RACH. - The UE transmits a RACH preamble to the target DU. - The target DU calculates the TA value and transmits it to the source DU via the CU. - The source DU transmits a cell(s) switch command including the TA value to the UE.

[0008] Therefore, it is possible to predict the TA value using a learning model and then use the predicted TA value to achieve RACH-less HO. However, in this case, there is a risk that the predicted value will become inappropriate due to changes in the UE movement and the propagation environment.

[0009] Therefore, the present disclosure has been made in consideration of such circumstances, and aims to provide a terminal that can calculate an appropriate predicted value of the TA value by utilizing a learning model.

[0010] One aspect of the disclosure is a terminal that is used to connect to a destination base station without performing random access, and includes a control unit (control unit 270) that calculates a predicted value of a transmission timing for transmitting data to the base station and a validity period of the transmission timing using a learning model, and a transmission unit (radio signal transmission / reception unit 210) that transmits the predicted value and the validity period to the base station.

[0011] FIG. 1 is a diagram illustrating an overall schematic configuration of a wireless communication system. FIG. 2 is a diagram illustrating a frequency range used in the wireless communication system. FIG. 3 is a diagram illustrating an example configuration of a wireless frame, subframe, slot, and symbol used in the wireless communication system. FIG. 4 is a functional block diagram of a terminal. FIG. 5 is a functional block diagram of a base station. FIG. 6 is a diagram illustrating an example architecture of a learning model. FIG. 7 is a flow diagram illustrating an example of whether to apply a predicted TA value calculated by a terminal. FIG. 8 is a flow diagram illustrating a case where a predicted TA value is applied based on a reliability score. FIG. 9 is a flow diagram illustrating a case where a predicted TA value is not applied based on a reliability score. FIG. 10 is a flow diagram illustrating an example of whether to apply a predicted TA value. FIG. 11 is a flow diagram illustrating an example of whether to apply a predicted TA value. FIG. 12 is a flow diagram illustrating FIG. 7 in more detail. FIG. 13 is a flow diagram illustrating an example of whether to apply a predicted TA value calculated by a source DU of a base station. FIG. 14 is a flow diagram illustrating an example of whether to apply a predicted TA value calculated by a target DU of a base station. Fig. 15 is a flow diagram showing an example of whether or not a predicted value of a TA value calculated by a gNB-CU of a source base station (source gNB) is applicable. Fig. 16 is a flow diagram showing an example of whether or not a predicted value of a TA value calculated by a gNB-CU of a destination base station (target gNB) is applicable. Fig. 17 is a flow diagram showing an example of whether or not a predicted value of a TA value calculated by a gNB-CU of a destination base station (target gNB) is applicable. Fig. 18 is a flow diagram showing an example of a case where HO performed using a predicted value of a TA value fails. Fig. 19 is a diagram showing an example of the hardware configuration of a base station and a terminal. Fig. 20 is a diagram showing an example of the configuration of a vehicle.

[0012] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0013] (1) Configuration of Wireless Communication System The wireless communication system 10 shown in Fig. 1 is a wireless communication system conforming to a method called 5G. Alternatively, the wireless communication system 10 may be a wireless communication system conforming to a method called Beyond 5G, 5G Evolution, or 6G.

[0014] The wireless communication system 10 can support Massive Multiple-Input Multiple-Output (Massive MIMO), which generates more directional beams by controlling wireless signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which uses multiple component carriers (CCs) as a bundle, and Dual Connectivity (DC), which enables simultaneous communication with two base stations.

[0015] As shown in FIG. 1 , the wireless communication system 10 includes a Next Generation-Radio Access Network (NG-RAN) 20, a base station 100 (hereinafter also referred to as a gNodeB (gNB) 100) connected to the NG-RAN 20, and a terminal 200 (hereinafter also referred to as a user equipment (UE) 200) that performs wireless communication with the gNB 100. The NG-RAN 20 is connected to a core network (CN) (not shown). The NG-RAN 20 and the CN may be simply referred to as a "network." The gNB 100 may also be considered to be included in the network. Note that the specific configuration of the wireless communication system 10, for example, the number of gNBs 100 and UEs 200, is not limited to the example shown in FIG. 1 .

[0016] The gNB100 may be a base station in a Centralized-Radio Access Network (C-RAN) configuration having a distributed unit (DU) having a function for connecting to the UE200 and a central unit (CU) having a function for connecting to the network. In this case, the gNB100 may be read as a DU, a CU, or a DU and a CU. When the gNB100 is a DU, it may be called a gNB-DU. When the gNB100 is a CU, it may be called a gNB-CU. When the gNB100 includes a DU and a CU, the DU portion may be called a gNB-DU and the CU portion may be called a gNB-CU.

[0017] The wireless communication system 10 may also support multiple frequency ranges (FR). That is, as shown in Fig. 2, the wireless communication system 10 may support the following FRs: FR1: 410 MHz to 7.125 GHz FR2-1: 24.25 GHz to 52.6 GHz FR2-2: Over 52.6 GHz to 71 GHz

[0018] In FR1, a subcarrier spacing (SCS) of 15, 30, or 60 kHz and a bandwidth (BW) of 5 to 100 MHz may be used, while in FR2-1, an SCS of 60 or 120 kHz (or even 240 kHz) and a BW of 50 to 400 MHz may be used.

[0019] In FR2-2, to avoid an increase in phase noise, Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) or Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) with a larger SCS may be applied.

[0020] 3, one slot in the wireless communication system 10 is composed of 14 symbols. If this configuration is maintained, the larger (wider) the SCS, the shorter the symbol period (and slot period). Note that the SCS is not limited to the frequencies shown in FIG. 3 and may be, for example, 480 kHz, 960 kHz, or other frequencies.

[0021] Furthermore, the number of symbols constituting one slot does not necessarily have to be 14, but may be, for example, 28 or 56. Furthermore, the number of slots per subframe may differ depending on the SCS.

[0022] (2) Functional Block Configuration of Wireless Communication System (2.1) Functional Block Configuration of Terminal As shown in FIG. 4, the UE 200 includes a wireless signal transmitting / receiving unit 210, an amplifier unit 220, a modulation / demodulation unit 230, a control signal / reference signal processing unit 240, an encoding / decoding unit 250, a data transmitting / receiving unit 260, and a control unit 270.

[0023] The radio signal transceiver 210 transmits and receives radio signals to and from the gNB 100. The radio signal transceiver 210 may be configured with a transmitter that transmits radio signals to the gNB 100 and a receiver that receives radio signals from the gNB 100. The radio signals may include data or may be interpreted as data. Transmission may be interpreted as report, notification, etc. Reception may be interpreted as (configured), (instructed), (notified), etc. Note that configuration may be realized by configuration information (information element (IE)) of the radio resource control (RRC) layer, and instruction may be realized by a control element (CE) or downlink control information (DCI) of the medium access control (MAC) layer.

[0024] The radio signal transceiver 210 of the embodiment can transmit a predicted value of the TA value to the gNB100 (for example, the gNB100 to which the UE 200 that performs HO is to transition). The TA value is a parameter that advances the transmission timing at which the UE 200 transmits data to the gNB100, and is a parameter that indicates the transmission timing for each UE 200. Therefore, it can be said that the TA value is the transmission timing for transmitting data to the gNB100 that is determined for each UE 200. Furthermore, the TA value is a parameter that is acquired in random access when connecting to the gNB100. In other words, if the TA value is available, it is possible to omit random access when connecting to the gNB100. Therefore, it can also be said that the TA value is a parameter that is used to connect to the gNB100 without performing random access.

[0025] The radio signal transceiver 210 of the embodiment can transmit not only the predicted value of the TA value but also the validity period of the TA value to the gNB100 (for example, the gNB100 to which the UE200 that performs HO is to be transferred). The validity period of the TA value may be interpreted as a period during which the transmission timing and the reception timing match (in terms of scheduling) when transmitting data from the UE200 to the gNB100. Note that the validity period of the TA value may be set in consideration of cases where the transmission timing and the reception timing no longer match due to changes over time, such as the movement of the UE200 or changes in the propagation environment.

[0026] The predicted TA value is a TA value calculated by the control unit 270 using a learning model. In other words, the predicted TA value is not a TA value calculated directly based on the actual environment or conditions, but a TA value that is estimated to be calculated in the current environment or conditions based on TA values ​​in past environments or conditions. The validity period of the TA value is the validity period of the TA value calculated by the control unit 270 using the learning model. Therefore, the validity period of the TA value in this embodiment is the validity period of the TA value estimated using the learning model (predicted validity period), just like the predicted TA value. The architecture of the learning model will be described later with reference to FIG. 6.

[0027] The radio signal transceiver 210 of the embodiment may transmit the reliability score calculated by the control unit 270 using the learning model to the gNB100 (e.g., the gNB100 to which the UE 200 performing HO is to be transferred). The reliability score may be a reliability score for a predicted value of the TA value or a reliability score for the validity period of the TA value. The reliability score may also be a reliability score for another parameter calculated by the control unit 270 using the learning model. The reliability score may be calculated as, for example, 90 points out of a maximum of 100 points.

[0028] The radio signal transceiver unit 210 of the embodiment may transmit a predicted value of the TA value when at least one of the following conditions is satisfied: When instructed by the gNB 100 to report a predicted value of the TA value (note that a specific instruction may be realized by an RRC configuration message, MAC CE, DCI, etc.) When the validity period of the TA value has expired (for example, when a timer that manages the validity period of the TA value has expired)

[0029] The amplifier unit 220 is configured by a power amplifier (PA) / low noise amplifier (LNA), etc. The amplifier unit 220 amplifies the radio signal output from the radio signal transmitting / receiving unit 210. The amplifier unit 220 also amplifies the radio signal output from the modulation / demodulation unit 230.

[0030] The modem unit 230 performs data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (gNB 100 or another gNB). CP-OFDM / DFT-S-OFDM may be applied in the modem unit 230. Furthermore, DFT-S-OFDM may be used not only for the uplink (UL) but also for the downlink (DL).

[0031] The control signal / reference signal processing unit 240 performs processing related to control signals transmitted and received between the gNB 100, such as radio resource control (RRC) signaling.

[0032] The control signal / reference signal processing unit 240 performs processing related to reference signals transmitted and received between the gNB 100, such as Demodulation Reference Signal (DMRS), Phase Tracking Reference Signal (PTRS), Channel State Information-Reference Signal (CSI-RS), Sounding Reference Signal (SRS), and Positioning Reference Signal (PRS).

[0033] The channels include control channels and data channels. The control channels include a physical uplink control channel (PUCCH), a physical downlink control channel (PDCCH), a physical random access channel (PRACH), a physical broadcast channel (PBCH), etc. The data channels include a physical uplink shared channel (PUSCH), a physical downlink shared channel (PDSCH), etc.

[0034] The encoding / decoding unit 250 performs division / concatenation and coding / decoding of data contained in the radio signal for each predetermined communication destination (gNB100 or another gNB).

[0035] Specifically, the encoding / decoding unit 250 decodes the data output from the modem unit 230 and concatenates the decoded data. In addition, the encoding / decoding unit 250 divides the data output from the data transmitter / receiver 260 into pieces of a predetermined size and performs coding on the divided data.

[0036] The data transmitter / receiver 260 assembles and disassembles data units (Protocol Data Units (PDUs) / Service Data Units (SDUs)) that make up data between each layer. The multiple layers include a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, and a Packet Data Convergence Protocol (PDCP) layer. The data transmitter / receiver 260 also performs data error correction and retransmission control based on Hybrid Automatic Repeat Request (HARQ).

[0037] The control unit 270 controls the UE 200. The control unit 270 controls, for example, transmission and reception of radio signals by the radio signal transmission and reception unit 210, amplification by the amplifier unit 220, data modulation / demodulation by the modem unit 230, signal processing by the control signal and reference signal processing unit 240, coding / decoding by the encoding / decoding unit 250, and assembly / disassembly of data units by the data transmission and reception unit 260.

[0038] The control unit 270 of the embodiment can execute HO of the UE 200, i.e., execute connection to the target gNB 100. Note that the HO executed by the control unit 270 may be HO in L3 or HO in L1 / L2, i.e., LTM. LTM is controlled in L1 / L2, which are layers lower than L3, and thus can complete HO in a shorter time than HO in L3.

[0039] In the embodiment, control unit 270 may perform random access with the transition destination gNB 100 in HO (LTM), or may not perform random access with the transition destination gNB 100. Hereinafter, the former HO may be referred to as RACH-based HO, and the latter HO may be referred to as RACH-less HO. RACH-less HO is realized by an early sync procedure in which UE 200 acquires a TA value in advance. Therefore, RACH-less HO may be understood as HO such as LTM or CHO to which the early sync procedure can be applied. These RACH-less HOs may also be referred to as RACH-less LTM and RACH-less CHO.

[0040] The control unit 270 of the embodiment can calculate a predicted value of the TA value using a learning model. As described in the explanation of the radio signal transceiver unit 210, the TA value is used to connect to the gNB 100 without performing random access, and is a parameter indicating the transmission timing for transmitting data to the gNB 100. Therefore, the predicted value of the TA value can also be said to be a parameter (predicted value of transmission timing) that is used to connect to the gNB 100 without performing random access, and indicates the transmission timing for transmitting data to the gNB 100. Furthermore, the control unit 270 can calculate the validity period of the TA value using the learning model. Furthermore, the control unit 270 may calculate a reliability score for the predicted value of the TA value or the validity period of the TA value.

[0041] In the embodiment, the control unit 270 may perform RACH-less HO when the gNB100 permits the use of a predicted value of the TA value, or may perform RACH-based HO when the gNB100 does not permit the use of a predicted value of the TA value. Furthermore, even when the gNB100 permits the use of a predicted value of the TA value, the control unit 270 may perform random access to the gNB100 (i.e., RACH-based HO) when connection with the gNB100 fails using the predicted value.

[0042] (2.2) Functional block configuration of base station As shown in Figure 5, the gNB 100 includes a radio signal transceiver unit 110, an amplifier unit 120, a modulation / demodulation unit 130, a control signal / reference signal processing unit 140, an encoding / decoding unit 150, a data transceiver unit 160, and a control unit 170.

[0043] In the following description, each component of the gNB100 may be interpreted as each component of the source gNB or each component of the target gNB. The source gNB may be interpreted as the gNB100 from which the UE200 is transitioned (hereinafter also referred to as gNB100A), and the target gNB may be interpreted as the gNB100 to which the UE200 is transitioned (hereinafter also referred to as gNB100B). Furthermore, the gNB100 in the embodiment may be interpreted as a gNB-CU, a gNB-DU, or both, as described above.

[0044] The radio signal transmitting / receiving unit 110 transmits and receives radio signals to and from the UE 200. The radio signal transmitting / receiving unit 110 may be configured with a transmitting unit that transmits radio signals to the UE 200 and a receiving unit that receives radio signals from the UE 200. The radio signals may include data or may be interpreted as data. Transmission may be interpreted as configuration, instruction, notification, etc. Reception may be interpreted as (reported), notification, etc. Note that configuration may be realized by configuration information (information element (IE)) of a radio resource control (RRC) layer, and instruction may be realized by a control element (CE) or downlink control information (DCI) of a medium access control (MAC) layer.

[0045] The radio signal transceiver 110 of the embodiment can have the same function as the radio signal transceiver 210 of the UE 200. That is, the radio signal transceiver 110 can transmit to the gNB 100B a predicted value of a parameter (TA value) that is used for the UE 200 to connect to the gNB 100B without performing random access and indicates the transmission timing for transmitting data to the gNB 100. Furthermore, the radio signal transceiver 110 can transmit to the gNB 100B a validity period of the TA value. The predicted value of the TA value and the validity period of the TA value transmitted by the radio signal transceiver 110 may be calculated by a control unit 170 of the gNB 100A that has the same function as the control unit 270 of the UE 200, using a learning model.

[0046] When the gNB100 is configured with a plurality of gNB-DUs and gNB-CUs, the radio signal transceiver 110 of the embodiment can transmit and receive data via the gNB-CU to and from the gNB-DU to which the UE200 is to be transferred. In this case, of the plurality of gNB-DUs, the gNB-DU from which the UE200 is to be transferred may be regarded as gNB100A, and the gNB-DU to which the UE200 is to be transferred may be regarded as gNB100B.

[0047] The radio signal transceiver 110 of the embodiment may transmit a reliability score for the predicted value of the TA value or the validity period of the TA value to the gNB 100B. The reliability score may be calculated by the control unit 170 of the gNB 100A using a learning model.

[0048] When the gNB100B permits the UE200 to use the predicted value of the TA value (use of the predicted value of the TA value when the UE200 performs RACH-less HO with respect to the gNB100B), the radio signal transmission / reception unit 110 of the embodiment may transmit the predicted value of the TA value to the UE200. In this case, the gNB100B may permit the UE200 to use the predicted value of the TA value based on the reliability score described above.

[0049] The radio signal transmitting and receiving unit 110 according to the embodiment may transmit the predicted value of the TA value included in a transition command (for example, a cell(s) switch command) to the UE 200.

[0050] The amplifier unit 120 is configured by a power amplifier (PA) / low noise amplifier (LNA), etc. The amplifier unit 120 amplifies the radio signal output from the radio signal transmitting / receiving unit 110. The amplifier unit 120 also amplifies the radio signal output from the modulation / demodulation unit 130.

[0051] The modem unit 130 performs data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (UE 200 or another UE). CP-OFDM / DFT-S-OFDM may be applied to the modem unit 130. Furthermore, DFT-S-OFDM may be used not only for the uplink (UL) but also for the downlink (DL).

[0052] The control signal and reference signal processor 140 performs processing related to control signals transmitted and received between the UE 200, such as radio resource control (RRC) signaling.

[0053] The control signal / reference signal processing unit 140 performs processing related to reference signals transmitted and received between the UE 200, such as a Demodulation Reference Signal (DMRS), a Phase Tracking Reference Signal (PTRS), a Channel State Information-Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), and a Positioning Reference Signal (PRS).

[0054] The channels include control channels and data channels. The control channels include a physical uplink control channel (PUCCH), a physical downlink control channel (PDCCH), a physical random access channel (PRACH), a physical broadcast channel (PBCH), etc. The data channels include a physical uplink shared channel (PUSCH), a physical downlink shared channel (PDSCH), etc.

[0055] The encoding / decoding unit 150 performs division / concatenation and coding / decoding of data included in a radio signal for each predetermined communication destination (UE 200 or another UE).

[0056] Specifically, the encoding / decoding unit 150 decodes the data output from the modem unit 130 and concatenates the decoded data. In addition, the encoding / decoding unit 150 divides the data output from the data transmitter / receiver 160 into pieces of a predetermined size and performs coding on the divided data.

[0057] The data transmitter / receiver 160 assembles and disassembles data units (Protocol Data Units (PDUs) / Service Data Units (SDUs)) that make up data between each layer. The multiple layers include a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, and a Packet Data Convergence Protocol (PDCP) layer. The data transmitter / receiver 160 also performs data error correction and retransmission control based on Hybrid Automatic Repeat Request (HARQ).

[0058] The control unit 170 controls the gNB 100. The control unit 170 controls, for example, the transmission and reception of radio signals by the radio signal transmission and reception unit 110, the amplification by the amplifier unit 120, the data modulation / demodulation by the modem unit 130, the signal processing by the control signal and reference signal processing unit 140, the coding / decoding by the encoding / decoding unit 150, and the assembly / disassembly of data units by the data transmission and reception unit 160. The control unit 170 also performs scheduling for the UE 200.

[0059] The control unit 170 of the embodiment can control HO by the UE 200, i.e., transition to the gNB 100B. Note that the HO controlled by the control unit 270 may be HO in L3 or HO in L1 / L2, i.e., LTM. By controlling LTM in L1 / L2, which are layers lower than L3, HO can be completed in a shorter time than HO in L3.

[0060] The control unit 170 of the embodiment may or may not perform random access with the UE 200 in the HO performed by the UE 200.

[0061] The control unit 170 of the embodiment can calculate a predicted value of the TA value using a learning model, similar to the control unit 270 of the UE 200. The control unit 170 can also calculate a validity period of the TA value using the learning model. Furthermore, the control unit 170 may calculate a reliability score for the predicted value of the TA value or the validity period of the TA value. The explanation of the TA value overlaps with the explanation above and is therefore omitted here.

[0062] The control unit 170 of the embodiment can permit the UE 200 to use a predicted TA value calculated by the control unit 170 itself or a predicted TA value calculated by the UE 200. In other words, the control unit 170 can verify whether the predicted TA value is appropriate and determine whether to use the predicted TA value. Such verification and determination can be performed based on the validity period of the TA value described above, or based on the reliability score for the predicted TA value or the validity period of the TA value described above. The UE 200 can perform RACH-less HO if the control unit 170 permits use, and can perform RACH-based HO if the gNB 100 does not permit use of the predicted TA value.

[0063] (2.3) Architecture of the Learning Model As shown in Fig. 6, the architecture of the learning model may include the following functions: Note that the architecture in Fig. 6 is the technology disclosed in Fig. 4.4-1 of 3GPP R2-2313107, and will be explained by referring to this as appropriate.

[0064] - "Data collection unit": Provides input data to the subsequent "model training unit," "management unit," and "estimation unit."

[0065] - "Model training unit": performs training of the learning model and stores the trained learning model in the "model storage unit."

[0066] - "Management Unit": Requests feedback on the performance of the learning model / retraining to the "Model Training Unit". Also, selects / enables (disables) / changes / fallbacks the learning model to the "Estimation Unit". Furthermore, requests the learning model from the "Model Storage Unit".

[0067] - "Estimation unit": Using the learning model stored in the "model storage unit", outputs a predicted value corresponding to the input data to the "management unit".

[0068] - "Model storage unit": stores the learning model and provides the learning model to the "estimation unit" in response to a request from the "management unit."

[0069] (3) Operation of the Wireless Communication System (3.1) Issues In the early sync procedure, the UE must go through many processes between the source gNB and the target gNB (or the source DU and the target DU in the case of inter-DU HO) before acquiring the TA value, which is a time-consuming process. Therefore, it is conceivable to predict the TA value using a learning model and realize RACH-less HO using the predicted TA value. However, in this case, there is a risk that the predicted value may become inappropriate due to UE movement or changes in the propagation environment.

[0070] (3.2) Operational Examples (3.2.1) Operational Example 1 Operational example 1 will be described with reference to Fig. 7 to Fig. 12. Operational example 1 is based on the premise that a learning model is installed in UE 200. That is, in operation example 1, it is UE 200 that calculates various parameters such as a predicted value of the TA value using the learning model.

[0071] The UE 200 can use the learning model to predict the TA value when performing HO to a candidate cell or neighbor cell formed by the gNB 100, and calculate the predicted value of the TA value. Note that the HO in this operation example may be HO to which RACH-less HO can be applied (such as LTM or CHO), or may be RACH-based HO (conventional HO).

[0072] As shown in Fig. 7, the UE 200 may calculate a predicted value of the TA value for each candidate cell and report it to the gNB 100 in a measurement report. In this case, a predicted value of a TAG value obtained by grouping the TA values ​​of multiple candidate cells may be reported. The UE 200 may also predict the validity period of each TA value (hereinafter also referred to as the TA timer) using a learning model and report it to the gNB 100 in a measurement report. An example is shown below. The measurement report may include measured values ​​of cell quality such as L1 / L3 Reference Signal Received Power (RSRP) according to the layer performing HO. Candidate cell A, B: predicted value of the TA value or TAG value, predicted value of the TA timer Candidate cell C: predicted value of the TA value, predicted value of the TA timer

[0073] Furthermore, when multiple TA values ​​can be set for one candidate cell, the UE 200 may calculate predicted values ​​of multiple TA values ​​using a learning model and report them to the gNB 100 in a measurement report. An example is shown below. Candidate cell D: predicted value 1 of the TA value, predicted value 1 of the TA timer, predicted value 2 of the TA value, predicted value 2 of the TA timer

[0074] Returning to Fig. 7, the gNB 100 verifies the predicted TA value received from the UE 200 and determines whether the UE 200 may use it in RACH-less HO. If the gNB 100 permits use of the predicted TA value, the gNB 100 transmits a transition command (e.g., a cell(s) switch command) to the UE 200. In response to this, the UE 200 performs RACH-less HO using the predicted TA value. Note that the transition command may include (anew) the transition destination candidate cell A and the TA value to be applied to candidate cell A.

[0075] The UE 200 may calculate a reliability score for the predicted value of the TA value or the validity period of the TA value and report this reliability score to the gNB 100. FIG. 8 shows a case where the reliability score is 90 or more out of 100, and FIG. 9 shows a case where the reliability score is less than 90 out of 100. In the case of FIG. 8, the gNB 100 permits the use of the predicted value of the TA value and instructs the UE 200 to perform RACH-less HO (cells switch command in the figure). In the case of FIG. 9, the gNB 100 does not permit the use of the predicted value of the TA value and instructs the UE 200 to perform RACH-based HO (PDCCH ordered RACH in the figure). Note that the threshold for determining whether the UE 200 should perform RACH-less HO or RACH-based HO is not limited to 90 or more out of 100, but may be 80 or more out of 100. The maximum reliability score is not limited to 100.

[0076] When performing RACH-less HO to a target cell, UE 200 can perform first transmission using the configured grant. In this case, the validity period of the configured grant is managed by a timer (e.g., cg-LTM-retransmissionTimer). UE 200 may also calculate (predict) the validity period of this configured grant using a learning model. Note that the configured grant is a pre-allocated PUSCH resource, and by using this resource, UL transmission can be performed without a scheduling request.

[0077] The TA value calculated by the UE 200 using the learning model may be a TA value in a Non-Terrestrial Network (NTN). In this case, the predicted value of the TA value may be the sum of a predicted value of the service link roundtrip time (service link RTT) and a predicted value of the common TA value. The network may use this predicted value of the TA value to perform K_offset configuration in scheduling.

[0078] There is a risk that a difference may occur in the calculated predicted value of the TA value depending on the vendor of the UE 200. To address this, the UE 200 may predict the offset of the TA value using a learning model (hereinafter, this predicted value is also referred to as an offset predicted value). Note that the offset predicted value may be set in the UE 200 by the gNB 100. In this case, the learning model may also be installed in the gNB 100, and the gNB 100 may calculate the offset predicted value using the learning model. The UE 200 may add the offset predicted value to the predicted value of the TA value and perform RACH-less HO.

[0079] When instructed by gNB100, UE200 may calculate a predicted value of the TA value using a learning model.

[0080] When instructed to report by the gNB 100, the UE 200 may report the predicted value of the TA value to the gNB 100. The timing of the report may be when a timer that manages the validity period of the predicted TA value expires, or when a timer that manages the validity period of an existing TA value (not predicted by a learning model) expires.

[0081] On the other hand, as shown in Fig. 10, it is not necessary to report the predicted value of the TA value. In this case, the UE 200 reports to the gNB 100, for example, via a measurement report, that the predicted value of the TA value has been calculated using the learning model. The gNB 100 determines whether or not to use the predicted value of the TA value, as in the description of Fig. 7, and transmits a transition command to the UE 200 in accordance with the decision.

[0082] 11 , when the UE 200 is notified by the gNB 100 to use the predicted value of the TA value, the UE 200 may autonomously calculate the predicted value of the TA value and further apply the predicted TA value to perform RACH-less HO to the target cell. In this case, the UE 200 may report the applied predicted value of the TA value and the destination cell ID to the gNB 100 after completing HO.

[0083] If the RACH-less HO described in this operation example fails, the UE 200 may fall back to the RACH-based HO.

[0084] Figure 12 shows a detailed flow of Figure 7, dividing gNB100 into a source gNB (gNB100A) and a target gNB (gNB100B). First, UE200 transmits a measurement report to gNB100A. In response to this, gNB100A requests / permits HO with gNB100 and transmits a candidate cell configuration to UE2000. The flow thereafter is the same as in Figure 7, so a description thereof will be omitted.

[0085] (3.2.2) Operation Example 2 Operation example 2 will be described with reference to Figures 13 to 17. Operation example 2 is based on the premise that a learning model is installed in the gNB 100. That is, in operation example 2, the gNB 100 is the entity that calculates various parameters such as a predicted value of the TA value using the learning model. Note that the HO in this operation example may be an HO (such as LTM or CHO) to which RACH-less HO can be applied, or may be a RACH-based HO (conventional HO).

[0086] (3.2.2.1) Operation Example 2-1 Operation example 2-1 is an operation example when a learning model is installed in a gNB-DU. In this case, the source DU may use the learning model to predict the TA value of a candidate cell and calculate the predicted TA value, or the target DU may use the learning model to predict the TA value of a candidate cell and calculate the predicted TA value. Note that the source DU, target DU, and CU are assumed to be included in the gNB100.

[0087] In the description of the operational example 2-1, the parts that have been described with reference to FIGS. 7 to 12 will be omitted as appropriate.

[0088] Fig. 13 shows a flow when a source DU predicts a TA value of a candidate cell using a learning model. The source DU transmits the predicted TA value to the target DU via the gNB-CU. The target DU determines whether or not the predicted TA value can be used, and if it is determined that it can be used, transmits this information to the source DU via the gNB-CU. The source DU transmits a transition command to the UE 200, as in Figs. 7 and 12.

[0089] Fig. 14 shows a flow when the target DU predicts the TA value of a candidate cell using a learning model. The source DU transmits the candidate cell (candidate cell A in the figure) to which UE200 is to be transferred to the target DU via the gNB-CU. The target DU calculates a predicted value of the TA value of the candidate cell using the learning model and transmits it to the source DU via the gNB-CU. The source DU transmits a transition command to UE200, similar to Figs. 7 and 12. In this case, the target DU or the source DU may decide whether or not to use the predicted TA value.

[0090] 13, similarly to FIGS. 8 and 9, the source DU may calculate and transmit not only the predicted value of the TA value but also its reliability score. The target DU may determine whether or not to use the predicted value of the TA value based on the reliability score. Similarly, in FIG. 14, the target DU may calculate not only the predicted value of the TA value but also its reliability score, and determine whether or not to use the predicted value of the TA value based on the reliability score.

[0091] In this operation example, as in operation example 1, the source DU may calculate and transmit a predicted value of a TAG value obtained by grouping the TA values ​​of multiple candidate cells. The source DU may also predict and transmit the validity period of each TA value (hereinafter also referred to as the TA timer). Furthermore, if multiple TA values ​​can be set for one candidate cell, the source DU may calculate and transmit predicted values ​​for the multiple TA values. Additionally, the validity period of the configured grant may also be calculated (predicted). Instead of the source DU, the target DU may calculate these predicted values.

[0092] (3.2.2.2) Operational Example 2-2 Operational example 2-2 is an operational example when a learning model is installed in a gNB-CU. In this case, the gNB-CU may predict the TA value of a candidate cell using the learning model and calculate the predicted TA value. More specifically, in the case of Inter-CU LTM or Inter-CU CHO, the gNB-CU of the source gNB (gNB100A) may predict the TA value of a candidate cell using the learning model and calculate the predicted TA value, or the gNB-CU of the target gNB (gNB100B) may predict the TA value of a candidate cell using the learning model and calculate the predicted TA value. Therefore, in Figures 15 to 17, the source gNB may be interpreted as meaning the gNB-CU of gNB100A, and the target gNB may be interpreted as meaning the gNB-CU of gNB100B.

[0093] In the description of the operational example 2-2, the parts that have been described with reference to FIGS. 7 to 14 will be omitted as appropriate.

[0094] 15, similarly to FIG. 13, the gNB-CU of the source gNB calculates a predicted value of the TA value using a learning model, and the gNB-CU of the target gNB determines whether to use the predicted value of the TA value. If it is determined that the predicted value of the TA value is to be used, the UE 200 applies the predicted value of the TA value to RACH-less HO.

[0095] 16, similarly to FIG. 14, the gNB-CU of the target gNB calculates a predicted value of the TA value using a learning model and transmits the predicted value of the TA value to UE 200 via the gNB-CU of the source gNB. UE 200 applies the predicted value of the TA value to RACH-less HO.

[0096] Fig. 17 shows a flow for performing RACH-less HO of CHO instead of LTM in Fig. 16. As described in Fig. 16, after transmitting a predicted value of the TA value to the UE 200, the UE 200 monitors the HO execution condition. If the HO execution condition is satisfied, the UE 200 performs RACH-less CHO.

[0097] 15, similarly to FIGS. 8 and 9, the gNB-CU of the source gNB (gNB100A) may calculate and transmit not only the predicted value of the TA value but also its reliability score. The gNB-CU of the target gNB (gNB100B) may determine whether or not to use the predicted value of the TA value based on the reliability score. Similarly, in FIGS. 16 and 17, the gNB-CU of the target gNB (gNB100B) may calculate not only the predicted value of the TA value but also its reliability score, and may determine whether or not to use the predicted value of the TA value based on the reliability score.

[0098] (4) Actions and Effects According to the above-described embodiment, by using the predicted value of the TA value calculated using the learning model and the validity period of the TA value, it is possible to simplify the early sync procedure while increasing the reliability of RACH-less HO.

[0099] In addition, by using a reliability score for the predicted value of the TA value, the reliability of RACH-less HO can be further improved.

[0100] Furthermore, if the timing of transmitting the predicted value of the TA value is based on instructions from gNB100, the transmission timing can be controlled on the gNB100 (network) side.

[0101] Furthermore, if the timing of transmitting the predicted TA value is based on the expiration of a timer that manages the validity period of the TA value, the predicted TA value can be updated efficiently.

[0102] In addition, the gNB100 can further increase the reliability of RACH-less HO by determining whether the predicted TA value is appropriate.

[0103] Furthermore, if RACH-less HO fails using the predicted TA value, the stability of communication can be ensured by falling back to RACH-based HO.

[0104] Furthermore, by transmitting the predicted value of TA included in a transition command (for example, a cell(s) switch command) to the UE 200, the UE 200 can quickly perform RACH-less HO using the predicted value of the TA value.

[0105] (5) Other Embodiments The contents of the present invention have been described above in accordance with the embodiments, but it will be obvious to those skilled in the art that the present invention is not limited to these descriptions and that various modifications and improvements are possible.

[0106] In the above disclosure, if HO using a predicted value of the TA value calculated by the UE 200 fails (or if RLF occurs), the UE 200 may report the predicted value of the TA value. As shown in Fig. 18 , the UE 200 may report the predicted value of the TA value by including it in a UEInformationResponse message (RLF report or RA report) in response to a UEInformationRequest message from the gNB 100.

[0107] In the above disclosure, the learning model may be applied to the O-RAN architecture. For example, if the learning model is installed in a Near-Real Time RIC, the Near-Real Time RIC may use the learning model to calculate a predicted value of the TA value. The predicted value of the TA value may be transmitted to the O-CU or O-DU via the E2 interface. In this case, in addition to the predicted value of the TA value, a reliability score for the predicted value of the TA value may also be transmitted.

[0108] In the above disclosure, it is assumed that one general-purpose learning model is used, but this is not limitative. Different learning models may be used depending on the content to be predicted.

[0109] The above-described operation examples may be combined and applied in a composite manner, as long as no contradiction occurs.

[0110] The block diagrams used to explain the above 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.

[0111] 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 these functions are implemented.

[0112] For example, the base station 100, the terminal 200, 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. 19 is a diagram illustrating an example of the hardware configuration of the base station 100 and the terminal 200 according to an embodiment of the present disclosure. The base station 100 and the terminal 200 described above 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.

[0113] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of base station 100 and terminal 200 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.

[0114] Each function in the base station 100 and the terminal 200 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and the memory 1002, causing the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0115] 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 device, an arithmetic unit, a register, etc.

[0116] 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. While the above-described various processes have been described as being executed by one processor 1001, they 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.

[0117] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to one embodiment of the present disclosure.

[0118] 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 storage medium may be, for example, a database, a server, or other suitable medium including at least one of memory 1002 and storage 1003.

[0119] 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 referred to as, for example, a network device, a network controller, a network card, a communication module, etc. 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).

[0120] 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).

[0121] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0122] Furthermore, base station 100 and terminal 200 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, processor 1001 may be implemented using at least one of these pieces of hardware.

[0123] 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., Radio Resource Control (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.

[0124] Each aspect / embodiment described in this disclosure may apply 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), New radio access (NX), Future generation radio access (FX), 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 any other suitable system, and next generation systems extended, modified, created, or defined based on these. In addition, multiple systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A with 5G).

[0125] 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.

[0126] In the present disclosure, a specific operation described as being performed by a base station may be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0127] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0128] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be transmitted to another device.

[0129] 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).

[0130] 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).

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0136] 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.

[0137] 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.

[0138] 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.

[0139] 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)). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or a base station subsystem that provides communication services within this coverage.

[0140] 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.

[0141] In this disclosure, terms such as "terminal," "user terminal," "Mobile Station (MS)," and "User Equipment (UE)" may be used interchangeably.

[0142] 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.

[0143] 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 an autonomous mobile object operating 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 Internet of Things (IoT) device such as a sensor.

[0144] Furthermore, the 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, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the terminal 200 may be configured to have the functions of the base station 100 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0145] Similarly, the term "terminal" in the present disclosure may be read as "base station." In this case, the base station 100 may be configured to have the functions of the terminal 200 described above.

[0146] 20 shows an example of the configuration of a vehicle 2001. As shown in Fig. 20, 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.

[0147] The drive unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor.

[0148] 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.

[0149] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2027 provided in the vehicle. The electronic control unit 2010 may also be called an Electronic Control Unit (ECU).

[0150] The signals from the various sensors 2021 to 2029 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.

[0151] 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 2001.

[0152] 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.

[0153] 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, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., inertial measurement units (IMUs), inertial navigation systems (INSs), etc.), artificial intelligence (AI) 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.

[0154] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 2029, which are provided in the vehicle 2001.

[0155] 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.

[0156] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021 to 2029 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 2029, 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.

[0157] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on the 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 received by the communication module 2013 (or data / information decoded from the PDSCH)).

[0158] Furthermore, the communication module 2013 stores 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, axle 2009, sensors 2021 to 2029, and the like provided in the vehicle 2001.

[0159] 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 a table, database, or other data structure), and ascertaining, all of which are considered to be "judging" and "determining." "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory), all of which are considered to be "judging" and "determining." "Determining" and "determining" may also include resolving, selecting, choosing, establishing, comparing, and other actions, all of which are considered to be "judging" and "determining." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Also, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0160] 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.

[0161] The reference signal may also be abbreviated as RS, and may be called a pilot depending on the applicable standard.

[0162] 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."

[0163] 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.

[0164] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0165] 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.

[0166] 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.

[0167] Numerology may be a communication parameter applied 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, specific windowing operations performed by the transceiver in the time domain, etc.

[0168] A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) A slot may be a time unit based on numerology.

[0169] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0170] 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.

[0171] 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 to 13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be referred to as a slot, minislot, etc., instead of a subframe.

[0172] 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 terminal by allocating radio resources (such as frequency bandwidth and transmission power that can be used by each terminal) in TTI units. However, the definition of TTI is not limited to this.

[0173] 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.

[0174] In addition, when one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Furthermore, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0175] A TTI having a time length of 1 ms may be referred to as a regular TTI (TTI in LTE Rel. 8 to 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.

[0176] 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.

[0177] 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.

[0178] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0179] 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.

[0180] 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. A bandwidth part (BWP) (which may also be referred to as a partial bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a certain numerology in a certain carrier. Here, the common RBs may be identified by their indexes relative to the common reference point of the carrier. PRBs may be defined in a certain BWP and numbered within the BWP.

[0181] 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.

[0182] 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."

[0183] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various configurations, such as 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, and the cyclic prefix (CP) length, can be changed.

[0184] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0185] 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.

[0186] 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."

[0187] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0188] (Additional Note) The above disclosure may be expressed as follows.

[0189] The first feature is a terminal that is used to connect to a destination base station without performing random access, and that includes: a control unit that calculates, using a learning model, a predicted value of a transmission timing for transmitting data to the base station and a validity period of the transmission timing; and a transmission unit that transmits the predicted value and the validity period to the base station.

[0190] A second feature is the terminal of the first feature, wherein the control unit calculates a reliability score for the predicted value, and the transmission unit transmits the reliability score to the base station.

[0191] A third feature is the terminal according to the first or second feature, wherein the transmitter transmits the predicted value when instructed by the base station to report the predicted value.

[0192] A fourth feature is the terminal according to any one of the first to third features, wherein the transmission unit transmits the predicted value when a timer that manages the validity period expires.

[0193] A fifth feature is the terminal according to any one of the first to fourth features, wherein the control unit connects to the base station without performing the random access when the base station permits use of the predicted value.

[0194] A sixth feature is the terminal according to the fifth feature, wherein the control unit executes the random access to the base station when connection with the base station fails.

[0195] 10 Wireless communication system 20 NG-RAN 100 Base station 110 Wireless signal transmitting / receiving unit 120 Amplifier unit 130 Modulation / demodulation unit 140 Control signal / reference signal processing unit 150 Encoding / decoding unit 160 Data transmitting / receiving unit 170 Control unit 200 Terminal 210 Wireless signal transmitting / receiving unit 220 Amplifier unit 230 Modulation / demodulation unit 240 Control signal / reference signal processing unit 250 Encoding / decoding unit 260 Data transmitting / receiving unit 270 Control unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device 1007 Bus 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Left and right front wheels 2008 Left and right rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 RPM sensor 2023 Air pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. A terminal comprising: a control unit that calculates a predicted value of a transmission timing for transmitting data to a target base station and a valid period of the transmission timing without performing random access, using a learning model; and a transmission unit that transmits the predicted value and the valid period to the base station.

2. The terminal according to claim 1, wherein the control unit calculates a reliability score for the predicted value, and the transmission unit transmits the reliability score to the base station.

3. The terminal according to claim 1, wherein the transmission unit transmits the predicted value when instructed by the base station to report the predicted value.

4. The terminal according to claim 1, wherein the transmission unit transmits the predicted value when a timer that manages the valid period expires.

5. The terminal according to claim 1, wherein the control unit connects to the base station without performing random access when the base station permits the use of the predicted value.

6. The terminal according to claim 5, wherein the control unit performs random access to the base station when the connection to the base station fails.

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