Terminal and communication method

Abstract

A terminal according to the present invention comprises: a transmission unit that transmits a signal pertaining to a request for recovery from a wireless link failure or a beam failure; a reception unit that receives a prescribed response to the request; and a control unit that executes prescribed monitoring on the basis of the execution timing of the recovery.

Description

Terminal and Communication Method

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

[0002] Technologies for further increasing the capacity of 3GPP (Registered Trademark) (3rd Generation Partnership Project) systems, further increasing the data transmission speed, and further reducing latency in the wireless section are being studied (for example, Non-Patent Document 1 and Non-Patent Document 2).

[0003] In 3GPP Release 19, for power reduction in a wireless communication system, technologies for a low-power wake-up signal (LP (Low Power)-WUS (Wake Up Signal)) and an LP-WUR (Wake Up Receiver) for receiving the LP-WUS are being discussed. Also, in the RRC_CONNECTED mode, which is a state where a radio resource control (RRC: Radio Resource Control) connection between a terminal and a base station is established, a procedure for triggering physical downlink control channel (PDCCH: Physical Downlink Control Channel) monitoring using the LP-WUS is being studied.

[0004] In previous Releases, for detecting radio link failure (RLF: Radio Link Failure) in a wireless communication system, radio link monitoring (RLM: Radio Link Monitoring) and its recovery (RLFR: Radio Link Failure Recovery) procedures have been studied (for example, Non-Patent Document 1). Also, in beamforming, a recovery (BFR: Beam Failure Recovery) procedure for detecting beam failure (BF: Beam Failure) and switching to another beam has been studied (for example, Non-Patent Document 1).

[0005] 3GPP TS 38.300 V18.2.0 (2024-06) 3GPP TS 38.401 V18.2.0 (2024-06)

[0006] In the current discussion, it has been confirmed that a terminal can trigger RLFR / BFR even when it is not performing PDCCH monitoring and is performing LP-WUS monitoring. When a terminal triggers RLFR / BFR, it autonomously activates PDCCH monitoring to receive the response to RLFR / BFR.

[0007] However, it has not been sufficiently considered whether a terminal performs LP-WUS monitoring while executing the RLFR / BFR procedure. Furthermore, it has not been sufficiently considered how a terminal resumes LP-WUS monitoring if it falls back to conventional PDCCH monitoring after executing the RLFR / BFR procedure. If LP-WUS monitoring is not properly performed during and after the execution of the RLFR / BFR procedure, there is a risk that the terminal may consume unnecessary power due to decreased power efficiency, etc.

[0008] This invention has been made in view of the above-mentioned problems, and aims to clarify the operation related to terminal monitoring in wireless communication recovery procedures and maintain the reliability of communication.

[0009] According to the disclosed technology, a terminal is provided having a transmitting unit that transmits a signal requesting the recovery of a radio link failure or beam failure, a receiving unit that receives a predetermined response to the request, and a control unit that performs predetermined monitoring based on the timing of the recovery.

[0010] According to the disclosed technology, the operation related to terminal monitoring in wireless communication recovery procedures can be clarified, and the reliability of the communication can be maintained.

[0011] Figure 1 is a diagram (1) showing an example of the configuration of a wireless communication system. Figure 2 is a diagram (2) showing an example of the configuration of a wireless communication system. Figure 3 is a diagram (1) for explaining communication using LP-WUS / LP-WUR. Figure 4 is a diagram (2) for explaining communication using LP-WUS / LP-WUR. Figure 5 is a diagram (1) showing an example of the procedure for LP-WUS to trigger PDCCH monitoring. Figure 6 is a diagram (2) showing an example of the procedure for LP-WUS to trigger PDCCH monitoring. Figure 7 is a diagram (3) showing an example of the procedure for LP-WUS to trigger PDCCH monitoring. Figure 8 is a diagram (4) showing an example of the procedure for LP-WUS to trigger PDCCH monitoring. Figure 9 is a diagram showing an example of the RRC re-establishment procedure during RLF. Figure 10 is a diagram showing an example of the PCell BFR procedure. Figure 11 is a flowchart showing an example of the operation of a terminal according to Embodiment 1. Figure 12 is a flowchart illustrating an example of terminal operation according to Example 2-1. Figure 13 is a flowchart illustrating an example of terminal operation according to Example 2-2. Figure 14 is a diagram illustrating an example of terminal operation according to Example 2-3. Figure 15 is a diagram illustrating an example of the functional configuration of a base station. Figure 16 is a diagram illustrating an example of the functional configuration of a terminal. Figure 17 is a diagram illustrating an example of the hardware configuration of a base station and a terminal. Figure 18 is a diagram illustrating an example of the vehicle configuration.

[0012] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the embodiments described below.

[0013] In the following explanation, " / " means "and / or" unless otherwise specified, or unless the context makes it clear that it has a different meaning.

[0014] In the operation of the wireless communication system of this embodiment, existing technologies will be used as appropriate. However, such existing technologies include, for example, existing LTE (Long Term Evolution), but are not limited to existing LTE. Furthermore, the term "LTE" as used herein has a broad meaning that includes LTE-Advanced and LTE-Advanced and later technologies (for example, NR (New Radio)), unless otherwise specified.

[0015] In the embodiments described below, terms such as Synchronization Signal (SS), Primary SS (PSS), Secondary SS (SSS), Physical Broadcast Channel (PBCH), Physical Random Access Channel (PRACH), Physical Downlink Control Channel (PDCCH), Physical Downlink Shared Channel (PDSCH), Physical Uplink Control Channel (PUCCH), and Physical Uplink Shared Channel (PUSCH), which are used in existing LTE systems, will be used. This is for convenience of description, and similar signals, functions, etc., may be called by other names. The above terms in NR may also be called SS, PSS, SSS, PBCH, PRACH, etc., without any particular distinction from LTE.

[0016] In this embodiment, the duplex scheme may be a time division duplex (TDD) scheme, a frequency division duplex (FDD) scheme, or any other scheme (for example, a flexible duplex).

[0017] In this embodiment, "configuring" wireless parameters means either pre-configuring predetermined values, or configuring wireless parameters notified by a base station or terminal.

[0018] <System Configuration> Figure 1 is a diagram (1) showing an example of the configuration of the wireless communication system in this embodiment. The wireless communication system in this embodiment includes a base station 10 and a terminal 20, as shown in Figure 1. Figure 1 shows one base station 10 and one terminal 20, but this is an example, and there may be multiple of each.

[0019] Base station 10 is a communication device that provides one or more cells and communicates wirelessly with terminal 20. The physical resources of the wireless signal are defined in the time domain and the frequency domain, 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 resource blocks. Base station 10 transmits synchronization signals and system information to terminal 20. Synchronization signals are, for example, PSS and SSS. System information is transmitted, for example, via PBCH or PDSCH, and is also called broadcast information. Synchronization signals and system information may be called a synchronization signal block (SSB: SS / PBCH Block). As shown in Figure 1, base station 10 transmits control signals or data to terminal 20 on the downlink (DL) and receives control signals or data from terminal 20 on the uplink (UL). Both base station 10 and terminal 20 are capable of transmitting and receiving signals using beamforming. Furthermore, both the base station 10 and the terminal 20 can apply Multiple Input Multiple Output (MIMO) communication to DL or UL. Also, both the base station 10 and the terminal 20 may communicate via secondary cells (SCell) and primary cells (PCell) using carrier aggregation (CA). Additionally, the terminal 20 may communicate via the PCell of base station 10 and the primary secondary cell group cell (PSCell) of other base stations 10 using dual connectivity (DC).

[0020] Terminal 20 is a communication device equipped with wireless communication capabilities, such as a smartphone, mobile phone, tablet, wearable device, or M2M (Machine-to-Machine) communication module. As shown in Figure 1, 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. Terminal 20 also receives various reference signals transmitted from the base station 10 and performs propagation path quality measurement based on the reception results of said reference signals.

[0021] Figure 2 is a diagram (2) showing an example of the configuration of the wireless communication system in this embodiment.

[0022] As shown in Figure 2, terminal 20 communicates with base station 10A and base station 10B provided by the NR system (hereinafter, when base station 10A and base station 10B are not distinguished, they may be referred to as "base station 10"). Furthermore, terminal 20 supports NR-NR dual connectivity, i.e., NR-DC, with base station 10A as the master node (MN) and base station 10B as the secondary node (SN). Terminal 20 can simultaneously transmit or receive with base station 10A and base station 10B by simultaneously utilizing multiple component carriers (CCs) provided by base station 10A (master node) and base station 10B (secondary node).

[0023] As shown in Figure 2, terminal 20 may communicate with base station 10A provided by the LTE system and base station 10B provided by the NR system. Furthermore, terminal 20 may support LTE-NR dual connectivity, i.e., EN-DC, where base station 10A is the MN and base station 10B is the SN. Terminal 20 can simultaneously transmit or receive with base station 10A, the master node, and base station 10B, the secondary node, by simultaneously utilizing multiple CCs provided by base station 10A, the master node, and base station 10B, the secondary node.

[0024] As shown in Figure 2, terminal 20 may communicate with base station 10A provided by the NR system and base station 10B provided by the LTE system. Furthermore, terminal 20 may support NR-LTE dual connectivity, i.e., NE (NR-E-UTRA)-DC, where base station 10A is the MN and base station 10B is the SN. Terminal 20 can simultaneously transmit or receive with base station 10A, the master node, and base station 10B, the secondary node, by simultaneously utilizing multiple CCs provided by base station 10A, the master node, and base station 10B, the secondary node.

[0025] As shown in Figure 2, terminal 20 may communicate with base station 10A and base station 10B provided by the NR system. Furthermore, terminal 20 may support NR-NR dual connectivity, i.e., NR-DC, where base station 10A is the MN and base station 10B is the SN. Terminal 20 can simultaneously transmit or receive with base station 10A, the master node, and base station 10B, the secondary node, by simultaneously utilizing multiple CCs provided by base station 10A, the master node, and base station 10B, the secondary node.

[0026] In this embodiment, terminal 20 may perform communication using one serving cell, or it may perform communication using multiple serving cells (for example, CA or DC). The processing operation in this embodiment may be performed with the system configuration shown in Figure 1, the system configuration shown in Figure 2, or any other system configuration.

[0027] <LP-WUS / LP-WUR> Figure 3 is a diagram (1) illustrating communication using LP-WUS / LP-WUR. In 3GPP Release 19, a power consumption reduction technology called "Low Power Wake Up Signal and Receiver" is under discussion. The Low Power Wake Up Signal is called LP-WUS or WUS, and the Low Power Wake Up Receiver is called LP-WUR, WUR, or LR. As shown in Figure 3(a), as an alternative to the Main Radio (MR) used in normal data communication, a state called Ultra Deep Sleep (UDS) is introduced by operating an LR, a simpler circuit that operates with lower power consumption than the MR. As shown in Figure 3(b), when the LR detects the LP-WUS and resumes communication with the base station 10, the power of the MR is turned ON. Thus, the power to the MR may be turned OFF or ON triggered by the LR receiving the LP-WUS signal. In other words, LP-WUS can be described as a control signal used to switch the state of the MR. Switching the state of the MR may be, for example, switching the power ON or OFF, or switching the power ON or sleep state. Alternatively, as explained in Figure 4 above, LP-WUS can be described as a signal indicating whether or not to monitor a paging opportunity (PO). Here, a paging opportunity means an opportunity in which the terminal 20 may receive paging. LP-WUS may be a predetermined sequence, or it may be information included in downlink control information (DCI) (for example, PEI (Paging Early Indication)).

[0028] Figure 4 is a diagram (2) illustrating communication using LP-WUS / LP-WUR. In 3GPP, the functional details of how the RRC connection status is applied are under discussion, regardless of whether it is RRC_CONNECTED, RRC_IDLE, or RRC_INACTIVE. It is being considered that the LP-WUS will be used to instruct PDCCH monitoring for RRC_CONNECTED, and the LP-WUS will be used to instruct paging monitoring for RRC_IDLE / RRC_INACTIVE. As shown in Figure 4, for example, in RRC_IDLE, LP-WUS is transmitted as information indicating whether or not the PO should be monitored. If the LR receives the LP-WUS and determines that the PO should be monitored, the MR is activated and subsequent processing is executed.

[0029] Next, the agreement regarding the scope of application of LP-WUS / LP-WUR in 3GPP Release 19 is shown below.

[0030] To specify an LP-WUS design that is common to both RRC_IDLE / RRC_INACTIVE mode and RRC_CONNECTED mode, an OFDM sequence is specified in which an on-off modulation (OOK: On Off Keying) (OOK-1 / OOK-4) based LP-WUS is overlaid on OOK symbols, and at least LP-WUS duty cycle monitoring is supported. In the LP-WUS design, it is necessary that the same information is delivered regardless of the LP-WUS type in RRC_IDLE / RRC_INACTIVE mode. The OFDM sequence may transmit information.

[0031] In RRC_IDLE / RRC_INACTIVE mode, the following three points are agreed upon:

[0032] (Agreement 1) Specifies the LP-WUS procedure and configuration for showing paging monitoring triggered by the LP-WUS. This procedure and configuration includes, at a minimum, the configuration, subgrouping, and entry / exit conditions for LP-WUS monitoring. (Agreement 2) Specifies a low-power synchronization signal (LP-SS) with a periodicity of Y [milliseconds] for the LP-WUR for Radio Resource Management (RRM) of the synchronization / serving cell. The LP-SS is based on an OOK-1 / OOK-4 waveform and may or may not have an OFDM sequence overlay. For LP-WURs that can receive existing PSS / SSS, the existing PSS / SSS may be used instead of the LP-SS for synchronization and RRM. (Agreement 3) Specify, including necessary conditions, that the RRM of the MR of terminal 20 be further relaxed in measurements of both the serving cell and adjacent cells, and that the RRM measurement of the serving cell of terminal 20 be offloaded from the MR to the LP-WUR.

[0033] In RRC_CONNECTED mode, the procedure for enabling and disabling LP-WUS monitoring, and for enabling monitoring of the MR PDCCH of terminal 20 triggered by LP-WUS, is specified. In RRC_CONNECTED mode, the MR UDS of terminal 20 is not considered, and the RRM / Radio Link Monitoring (RLM) / Beam Failure Detection (BFD) / Channel State Information (CSI) measurements of terminal 20 are performed by MR.

[0034] The target coverage for LP-WUS and LP-SS is the coverage of PUSCH in message 3. Optimization of the LP-WUS signal design for RRC_IDLE / RRC_INACTIVE modes takes precedence over optimization for RRC_CONNECTED mode.

[0035] 3GPP Release 19 describes a procedure for triggering PDCCH monitoring using LP-WUS in RRC_CONNECTED mode. In this procedure, LP-WUS is, for example, LP-WUS with C-DRX settings. The following four options are discussed in this procedure:

[0036] Figure 5 is a diagram (1) showing an example of the procedure by which LP-WUS triggers PDCCH monitoring. In Option 1, as shown in Figure 5, terminal 20 performs LP-WUS monitoring according to the LP-WUS monitoring settings before triggering the start of drx-onDurationTimer. Option 1 can be applied to the DCP (DCI format 2_6 with CRC (Cyclic Redundancy Check) scrambled by PS-RNTI (Power Saving - Radio Network Temporary Identifier)) function. Here, drx-onDurationTimer is one of the parameters of the DRX function and means the period during which terminal 20 performs PDCCH monitoring within the DRX cycle. DCP also means a signal transmitted using DCI format 2-6 to control the activation of terminal 20.

[0037] In Option 2, as shown in Figure 6, terminal 20 performs LP-WUS monitoring at least outside of the legacy C-DRX active period in accordance with the LP-WUS monitoring settings to trigger PDCCH monitoring. In Option 2, PDCCH monitoring may be performed regardless of drx-onDurationTimer.

[0038] Figure 6 is a diagram (2) showing an example of the procedure by which LP-WUS triggers PDCCH monitoring. In Option 2-1, which is related to Option 2, PDCCH monitoring is additionally triggered based on the legacy C-DRX cycle and drx-onDurationTimer during LP-WUS monitoring, as shown in Figure 6. To adopt Option 2-1, it is necessary to configure it together with Option 1 to achieve power savings compared to legacy C-DRX.

[0039] Figure 7 is a diagram (3) showing an example of the procedure by which LP-WUS triggers PDCCH monitoring. In Option 2-2, which is related to Option 2, as shown in Figure 7, PDCCH monitoring is not triggered by the legacy C-DRX cycle and drx-onDurationTimer during LP-WUS monitoring.

[0040] Figure 8 is a diagram (4) illustrating an example of the procedure by which LP-WUS triggers PDCCH monitoring. In Option 3, as shown in Figure 8, LP-WUS monitoring is performed at least during the legacy C-DRX active time, according to the LP-WUS monitoring settings for triggering PDCCH monitoring.

[0041] <RLM / RLFR> Figure 9 shows an example of the RRC re-establishment procedure during RLF. Terminal 20 declares RLF, for example, when the radio problem timer (T301), which was started after a radio problem instruction from the physical layer, expires. If the radio problem is resolved before the radio problem timer expires, terminal 20 stops the radio problem timer.

[0042] After RLF is declared, the terminal 20 remains in RRC_CONNECTED in certain cases. In other cases, in the case of RLF of the serving cell, or in the case of DAPS (Dual Active Protocol Stack) handover standardized in 3GPP Release 16, or in the case of RLF of the target cell before releasing the source cell, the terminal 20 selects an appropriate cell and starts the procedure for RRC re-establishment. If an appropriate cell is not found within a certain time after RLF is declared, the terminal 20 enters RRC_IDLE.

[0043] <BFD / BFR> Figure 10 is a diagram showing an example of the BFR procedure of the PCell.

[0044] Use the SSB that is QCL (Quasi-Co-Location) with the periodic CSI-RS (Reference Signal) and the reference signal for PDCH demodulation (DMRS: DeModulation Reference Signal) for BFD.

[0045] Here, QCL is an index indicating the statistical properties of a channel. For example, when a certain signal / channel and another signal / channel are in a QCL relationship, among these different multiple signals / channels, it may be assumed that at least one of the Doppler shift, Doppler spread, average delay, delay spread, spatial parameters (for example, spatial reception filter / spatial reception parameters), spatial transmission filter / spatial transmission parameters is the same (QCL with respect to at least one of these).

[0046] Note that the spatial reception parameter may correspond to the reception beam (such as the reception analog beam) of the terminal 20, and the beam may be specified based on spatial QCL. The QCL (or at least one element of QCL) in the present disclosure may be read as spatial QCL (sQCL).

[0047] The terminal 20 triggers the BFR by starting a random access procedure on the PCell. When the random access procedure is completed, the BFR of the PCell is considered completed.

[0048] The terminal 20 triggers the BFR by starting the transmission of a BFR MAC CE (Medium Access Control Control Element) to the SCell. When a PDCCH indicating a UL grant for a new transmission is received on the HARQ process used for the transmission of the BFR MAC CE, the BFR of the SCell is considered completed.

[0049] Here, the random access (RA) procedure includes contention-based random access (CBRA) and contention-free random access (CFRA). In CBRA, a 4-step RA procedure or a 2-step RA procedure is performed.

[0050] In the 4-step RA procedure, the following four messages are exchanged between the terminal 20 and the base station 10.

[0051] [Step 1] Randomly select an RA preamble and transmit the PRACH (Message 1 from the terminal 20 to the base station 10) [Step 2] Transmit a random access response (RAR) (Message 2 from the base station 10 to the terminal 20) [Step 3] Transmit a signal from the upper layer (Message 3 from the terminal 20 to the base station 10) [Step 4] Transmit control information for RRC connection (Message 4 from the base station 10 to the terminal 20)

[0052] In the 2-step RA procedure, the following two messages are exchanged between the terminal 20 and the base station 10.

[0053] [Step 1] Terminal 20 sends message A to base station 10, which includes an RA preamble and a PUSCH that transmits predetermined information for initial access (corresponding to messages 1 and 3 above). [Step 2] Base station 10 sends message B to terminal 20 in response to message A (corresponding to messages 2 and 4 above).

[0054] <Issues> When considering the case where LP-WUS monitoring / PDCCH monitoring and the RLFR procedure / BFR procedure are executed simultaneously, it has been confirmed in the current discussion that terminal 20 can trigger RLFR / BFR even when terminal 20 is not performing PDCCH monitoring and is performing LP-WUS monitoring. When terminal 20 triggers RLFR / BFR, terminal 20 autonomously activates PDCCH monitoring in order to receive the response to RLFR / BFR.

[0055] However, it has not been sufficiently considered whether terminal 20 performs LP-WUS monitoring while executing the RLFR procedure / BFR procedure. Furthermore, it has not been sufficiently considered how the terminal resumes LP-WUS monitoring if it falls back to conventional PDCCH monitoring after executing the RLFR procedure / BFR procedure. If LP-WUS monitoring is not properly performed during and after the execution of the RLFR procedure / BFR procedure, there is a risk that the terminal may consume unnecessary power due to deterioration of power efficiency, etc.

[0056] This embodiment clarifies the operation related to terminal monitoring in the wireless communication recovery procedure.

[0057] The following describes an embodiment of this design. In the following embodiment, the "RLFR / BFR recovery procedure" may simply be called the recovery procedure.

[0058] The operation of terminals related to LP-WUS monitoring / PDCCH monitoring during the RLFR procedure / BFR procedure may also be specified.

[0059] Once terminal 20 initiates the RLFR procedure / BFR procedure, terminal 20 may anticipate a predetermined LP-WUS monitoring operation / predetermined PDCCH monitoring operation in order to receive a predetermined response from base station 10 during the recovery procedure.

[0060] <Example 1-1> The "predetermined LP-WUS monitoring operation / predetermined PDCCH monitoring" described above may be one or more of the following methods (Alt: Alternative).

[0061] [Alt. 1] Terminal 20 may continue monitoring LP-WUS to trigger PDCCH monitoring. [Alt. 2] Terminal 20 may fall back to PDCCH monitoring as legacy. That is, terminal 20 may perform conventional PDCCH monitoring. [Alt. 3] Terminal 20 may assume one or more of [Alt. 1] to [Alt. 2] depending on the implementation of terminal 20. [Alt. 4] Terminal 20 may assume one or more of [Alt. 1] to [Alt. 3] depending on the settings of base station 10. Base station 10 may notify terminal 20 of the settings by System Information (SI) / RRC / MAC CE / DCI, etc. [Alt. 5] Terminal 20 may assume one or more of [Alt. 1] to [Alt. 4] depending on the capabilities of terminal 20. Terminal 20 may assume [Alt. The base station 10 may report that it supports one or more of the following: [1] to [Alt. 4].

[0062] Figure 11 is a flowchart showing an example of the operation of the terminal according to Embodiment 1.

[0063] In step S101, terminal 20 starts the RLFR procedure / BFR procedure. In step S102, terminal 20 may perform Alt. 1, Alt. 2, or Alt. 3 to Alt. 5 described above for the LP-WUS monitoring operation / PDCCH monitoring operation.

[0064] <Example 1-2> The "predetermined response from base station 10" described above may be one or more of the following responses.

[0065] [Alt. 1] Response to RLFR. [Alt. 2] RRC signaling including an RRC message for RLFR. The RRC message may be, for example, RRCReestablishment / RRCReconfiguration. [Alt. 3] Response to BFR by CBRA. [Alt. 4] Response to BFR by CFRA. [Alt. 5] Response to BFR by BFR MAC CE. [Alt. 6] PDCCH / Message 2 / Message 4 / Message B with PDCCH / C(Cell)-RNTI indicating a UL grant for BFR MAC CE in response to BFR.

[0066] <Example 1-3> In the case of Example 1-1 / Example 1-2, the same or different LP-WUS monitoring operation / PDCCH monitoring operation may be performed for different responses from the base station 10.

[0067] For example, terminal 20 may perform LP-WUS monitoring for BFRs triggered by BFR MAC CE. For example, terminal 20 may fall back to performing legacy PDCCH monitoring for BFRs triggered by CBRA. For example, terminal 20 may perform LP-WUS monitoring for RLFRs.

[0068] <Example 1-4> [Alt. 2] in Example 1-1 may be implemented as follows.

[0069] (1) Terminal 20 sends a UL to indicate RLF / BF. The UL may be PRACH / SR (Scheduling Request) / CG (Configured Grant)-PUSCH / MAC CE, etc. (2) When terminal 20 sends the UL, terminal 20 falls back to perform PDCCH monitoring. The PDCCH monitoring may be performed based on the C-DRX setting or not based on the C-DRX setting. "The PDCCH monitoring is performed not based on the C-DRX setting" may mean "The PDCCH monitoring is performed at all times". Note that "C-DRX is set" may mean that predetermined parameters related to the DRX function are set. The "predetermined parameters related to the DRX function" may be at least one of the following, for example: drx-Config, drx-ConfigExt, drx-ConfigExt2, drx-ConfigSecondaryGroup, drx-ConfigSL, drx-ConfigPTM, etc.

[0070] As shown in the configuration of Example 1, controlling the monitoring operation of the terminal during the recovery procedure makes it possible to achieve both terminal power efficiency and communication reliability.

[0071] The operation of the terminal related to LP-WUS monitoring / PDCCH monitoring after the RLFR procedure / BFR procedure may also be specified.

[0072] <Example 2-1> After the completion of the RLFR procedure / BFR procedure, terminal 20 may perform one or more of the following operations in LP-WUS monitoring / PDCCH monitoring.

[0073] [Alt. 1] Terminal 20 may be assumed to perform LP-WUS monitoring to trigger PDCCH monitoring. [Alt. 2] Terminal 20 may assume PDCCH monitoring as legacy. That is, terminal 20 may assume conventional PDCCH monitoring. The PDCCH monitoring may be performed based on the C-DRX setting or not based on the C-DRX setting. "The PDCCH monitoring is performed not based on the C-DRX setting" may mean "The PDCCH monitoring is performed at all times." Note that "C-DRX is set" may mean that predetermined parameters related to the DRX function are set. "Predetermined parameters related to the DRX function" may be at least one of, for example, drx-Config, drx-ConfigExt, drx-ConfigExt2, drx-ConfigSecondaryGroup, drx-ConfigSL, drx-ConfigPTM, etc. [Alt. [Alt. 4] Terminal 20 may be assumed to follow the same operation as during the recovery procedure. For example, if terminal 20 monitors PDCCH as legacy during the recovery procedure, terminal 20 may continue to monitor PDCCH as legacy after the recovery procedure. For example, if terminal 20 monitors LP-WUS during the recovery procedure, terminal 20 may continue to monitor LP-WUS after the recovery procedure. [Alt. 4] Terminal 20 may assume one or more of [Alt. 1] to [Alt. 3] depending on the implementation of terminal 20. [Alt. 5] Terminal 20 may assume one or more of [Alt. 1] to [Alt. 4] depending on the settings of base station 10. Base station 10 may notify terminal 20 of the settings by SI / RRC / MAC CE / DCI, etc. [Alt. 6] Terminal 20 may assume [Alt. 1] to [Alt. 4] depending on the capabilities of terminal 20. One or more of [5] may be assumed. Terminal 20 may report to base station 10 that it supports one or more of [Alt. 1] to [Alt. 5].

[0074] Figure 12 is a flowchart showing an example of the operation of the terminal according to Example 2-1.

[0075] In step S201, terminal 20 completes the RLFR procedure / BFR procedure. In step S202, terminal 20 may perform Alt. 1, Alt. 2, Alt. 3, or Alt. 4 to Alt. 6 described above for the LP-WUS monitoring operation / PDCCH monitoring operation.

[0076] <Example 2-2> If the measured channel status is sufficiently good, terminal 20 may perform LP-WUS monitoring after the recovery procedure.

[0077] The "measured channel state" may be, for example, Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), Received Signal Strength Indicator (RSSI), Signal to Interference plus Noise Ratio (SINR), or other metrics.

[0078] "The measured channel condition is sufficiently good" means, for example, that the channel condition measured by MR / LR using LP-SS / LP-WUS / LP-WUS preamble / CSI-RS exceeds a predetermined threshold. This predetermined threshold may be specified in advance in the specifications, set by SIB / RRC, or indicated by MAC CE / DCI.

[0079] Figure 13 is a flowchart showing an example of the operation of the terminal according to Example 2-2.

[0080] In step S301, terminal 20 completes the RLFR procedure / BFR procedure. In step S302, terminal 20 determines whether the channel condition measured by terminal 20 is good or not. If the channel condition measured by terminal 20 is good (step S303: Yes), terminal 20 may perform LP-WUS monitoring. On the other hand, if the channel condition measured by terminal 20 is not good (step S304: No), terminal 20 does not have to perform LP-WUS monitoring.

[0081] As shown in Example 2-2, a configuration that determines the resumption of LP-WUS monitoring based on the channel status allows for the dynamic optimization of the balance between communication quality and power saving.

[0082] <Example 2-3> If the LP-WUS monitoring operation / PDCCH monitoring operation differs during and after the recovery procedure, terminal 20 may assume that the LP-WUS monitoring operation / PDCCH monitoring operation will be applied from one or more offsets onward.

[0083] [Alt. 1] Offset n1 after RLFR completion. [Alt. 2] Offset n2 after terminal 20 receives a predetermined RRC message or after terminal 20 sends a predetermined RRC message. The predetermined RRC message received may be, for example, RRCReestablishment / RRCReconfiguration. The predetermined RRC message sent may be, for example, RRCReestablishmentComplete / RRCReconfigurationComplete. [Alt. 3] Offset n3 after BFR completion. [Alt. 4] Offset n4 after completion of the CBRA procedure / CFRA procedure for BFR completion. [Alt. 5] Offset n5 after terminal 20 receives a PDCCH / Message 2 / Message 4 / Message B with a PDCCH / C-RNTI indicating a UL grant in response to BFR. [Alt. 6) Offset n6 after terminal 20 transmits an acknowledgment (HARQ-ACK: Hybrid Automatic Repeat reQuest - ACKnowledgement) for the PDSCH that transmits the BFR response. [Alt. 7] Offset n7 after terminal 20 obtains a measurement metric related to the channel state after the recovery procedure.

[0084] Figure 14 shows an example of the operation of the terminal according to Example 2-3.

[0085] After the RLFR / BFR procedure is triggered by terminal 20, terminal 20 performs PDCCH monitoring as legacy during the RLFR / BFR procedure. After the RLFR / BFR procedure is completed, terminal 20 applies an Alt. 1 or Alt. 3 offset and switches to LP-WUS monitoring.

[0086] The units for offsets n1 to n7 above may also be seconds / milliseconds / wireless frames / wireless frame numbers (SFN: System Frame Number) / subframes / slots / symbols.

[0087] The above offsets n1 to n7 may be non-negative integers. If the above offsets n1 to n7 are 0, it may mean that no offset is specified. The above offsets n1 to n7 may be specified in advance by the base station 10, or they may be specified in advance according to the subcarrier interval.

[0088] In the base station configurations described in Examples 2-1, 2-2, and 2-3 above, the base station configuration may be transmitted via RRC / SI / DCI / MAC CE. Furthermore, the base station configuration may be shown before, during, or after the recovery procedure.

[0089] For example, the base station settings in the above-described examples 2-1 / 2-2 / 2-3 may be transmitted in PDCCH in response to a BFR initiated by the CBRA / CFRA / BFR MAC CE. For example, the base station settings in the above-described examples 2-1 / 2-2 / 2-3 may be transmitted in RRC of RLFR.

[0090] As shown in Example 2-3, by setting an offset related to the switching of the monitoring method after the recovery procedure is completed, optimal monitoring control can be achieved according to the network status and requirements.

[0091] Based on the above, the operation of the terminal after the completion of the recovery procedure as in Example 2 makes it possible to maintain communication reliability while achieving both efficient resource utilization and power saving of the terminal.

[0092] <Device Configuration> An example of the functional configuration of the base station 10 and terminal 20 that perform the processing and operations described above will be explained. The base station 10 and terminal 20 include the functions to carry out the embodiments described above. However, the base station 10 and terminal 20 may each be equipped with only some of the functions in the embodiments.

[0093] ≪Base Station≫ Figure 15 shows an example of the functional configuration of a base station. 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 Figure 15 is merely an example. Any functional classification and functional unit names are acceptable as long as they can perform the operations according to this embodiment.

[0094] The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The transmitting unit 110 also transmits setting information, instructions, and notifications related to the low-power wake-up signal to the terminal 20. The transmitting unit 110 also transmits notifications to the terminal regarding the switching of monitoring operations. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 and obtaining information from the received signals, for example, information from a higher layer. The transmitting unit 110 also has the function of transmitting PSS, SSS, PBCH, DL / UL control signals, etc. to the terminal 20. The receiving unit 120 also receives inter-network node messages from other network nodes.

[0095] The setting unit 130 stores pre-set setting information and various setting information to be transmitted to the terminal 20. The content of the setting information includes, for example, information related to measurements in low-power signals.

[0096] As described in the embodiment, the control unit 140 performs control related to settings, instructions, and notifications concerning LP-WUS, etc. The signal transmission function unit of the control unit 140 may be included in the transmission unit 110, and the signal reception function unit of the control unit 140 may be included in the reception unit 120.

[0097] ≪Terminal≫ Figure 16 shows an example of the functional configuration of a terminal. 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 Figure 16 is just one example. Any functional classification and name of functional unit is acceptable as long as it can perform the operations according to this embodiment. The transmitting unit 210 and the receiving unit 220 may be collectively referred to as the communication unit.

[0098] The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The transmitting unit 210 also transmits capability information related to LP-WUS to the base station 10. The receiving unit 220 wirelessly receives various signals and acquires signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving PSS, SSS, PBCH, DL / UL / SL control signals, etc. transmitted from the base station 10. The receiving unit 220 also receives paging notification information, setting information, instructions, and notifications related to LP-WUS from the base station 10. For example, the receiving unit 220 receives LP-WUS from the base station 10. The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores pre-set setting information. The content of the setting information is, for example, information related to measurements in LP-WUS.

[0099] As described in the embodiment, the control unit 240 performs control related to setting, instructing, and notifying of LP-WUS. The control unit 240 may decide whether or not to perform LP-WUS monitoring. The control unit 240 may perform LP-WUS monitoring. The control unit 240 does not have to assume that LP-WUS monitoring is set. The control unit 240 may detect LP-WUS by performing LP-WUS monitoring. The signal transmission function unit of the control unit 240 may be included in the transmission unit 210, and the signal reception function unit of the control unit 240 may be included in the reception unit 220.

[0100] <Hardware Configuration> The block diagrams (Figures 15 and 16) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may be realized by combining the one device or the multiple devices with software.

[0101] Functions include, but are not limited to, judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. In all cases, as mentioned above, the method of implementation is not particularly limited.

[0102] Figure 17 shows an example of the hardware configuration of a base station and a terminal. For example, the base station 10 and terminal 20 in this embodiment may function as computers that process the wireless communication method of this embodiment. The base station 10 and terminal 20 described above may be physically configured as computer devices including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0103] In the following explanation, the term "device" can be replaced with "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and terminal 20 may include one or more of the devices shown in the figure, or it may be configured without some of the devices.

[0104] Each function in the base station 10 and terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of data reading and writing in the storage device 1002 and auxiliary storage device 1003.

[0105] The processor 1001 controls the entire computer, for example, by running an operating system (OS). The processor 1001 may consist of a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.

[0106] Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes the computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 140 of the base station 10 shown in Figure 15 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in Figure 16 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above-described processes have been explained 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 program may also be transmitted from the network via a telecommunications line.

[0107] The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of the present disclosure.

[0108] The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc 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 multipurpose disk, a Blu-ray® disk), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0109] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may be configured to include, for example, a high-frequency switch, duplexer, filter, frequency synthesizer, etc., in order to implement at least one of FDD and TDD. For example, the transmitting / receiving antenna, amplifier section, transmitting / receiving section, transmission path interface, etc., may be implemented by the communication device 1004. The transmitting / receiving section may be implemented in a physically or logically separated manner, with a transmitting section and a receiving section.

[0110] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED (Light-Emitting Diode) lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0111] Furthermore, each device, such as the processor 1001 and the storage device 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or different buses may be configured for each device.

[0112] Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0113] Figure 18 shows an example of the configuration of a vehicle. The vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, 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. Each aspect / embodiment described in this disclosure may be applied to a communication device mounted on the vehicle 2001, for example, to the communication module 2013.

[0114] The drive unit 2002 consists of, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel, which is operated by the user.

[0115] The electronic control unit 2010 consists of a microprocessor 2031, memory (ROM, RAM) 2032, and communication ports (I / O (Input / Output) ports) 2033. Signals from various sensors 2021 to 2029 installed in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0116] Signals from various sensors 2021 to 2029 include current signals from current sensor 2021 for sensing motor current, front or rear wheel rotation speed signals acquired by rotation speed sensor 2022, front or rear wheel air pressure signals acquired by air pressure sensor 2023, vehicle speed signals acquired by vehicle speed sensor 2024, acceleration signals acquired by acceleration sensor 2025, accelerator pedal depression signals acquired by accelerator pedal sensor 2029, brake pedal depression signals acquired by brake pedal sensor 2026, shift lever operation signals acquired by shift lever sensor 2027, and detection signals acquired by object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.

[0117] The Information Service Unit 2012 consists of various devices for providing (outputting) various types of information such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, television, and radio, and one or more ECUs that control these devices. The Information Service Unit 2012 uses information acquired from external devices via a communication module 2013, etc., to provide various multimedia information and multimedia services to the occupants of the vehicle 2001. The Information Service Unit 2012 may include input devices that accept input from the outside (e.g., keyboard, mouse, microphone, switch, button, sensor, touch panel, etc.) and output devices that perform output to the outside (e.g., display, speaker, LED lamp, touch panel, etc.).

[0118] The driver assistance system unit 2030 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS (Global Navigation Satellite System)), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System)), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driver assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize driver assistance functions or autonomous driving functions.

[0119] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via its communication port. For example, the communication module 2013 sends and receives data via the communication port 2033 between the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, the microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021-29 provided in the vehicle 2001.

[0120] 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 external devices. For example, it can send and receive various types of information with external devices 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 or a mobile station.

[0121] The communication module 2013 may transmit at least one of the following to an external device via wireless communication: signals from the various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on said signals, and information based on input from an external source (user) obtained via the information service unit 2012. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc., may also be called input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include the information based on the above input.

[0122] The communication module 2013 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from an external device and displays it on the information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may also be called an output unit, which outputs information (for example, outputs information to devices such as displays and speakers based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from the external device 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, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021-2029, etc., provided in the vehicle 2001.

[0123] For example, embodiments of the present invention are as follows:

[0124] <1> A terminal comprising: a transmitting unit that transmits a signal requesting recovery from a radio link failure or beam failure; a receiving unit that receives a predetermined response to the request; and a control unit that performs predetermined monitoring based on the timing of the recovery. <2> The terminal according to <1>, wherein the control unit performs monitoring of a low-power wake-up signal while the recovery is being performed. <3> The terminal according to <1> or <2>, wherein the control unit performs monitoring of a physical downlink control channel while the recovery is being performed. <4> The terminal according to any one of <1> to <3>, wherein the control unit performs monitoring of a low-power wake-up signal after the recovery is completed. <5> The terminal according to any one of <1> to <4>, wherein the control unit performs monitoring of a physical downlink control channel after the recovery is completed. <6> A communication method performed by a terminal comprising: transmitting a signal requesting recovery from a radio link failure or beam failure; receiving a predetermined response to the request; and performing predetermined monitoring based on the timing of the recovery.

[0125] In any of the above configurations, the operation related to terminal monitoring in the wireless communication recovery procedure can be clearly defined, and the reliability of the communication can be maintained.

[0126] <Supplement to Embodiments> Although these embodiments have been described above, the disclosed invention is not limited to these embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but 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, and matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. The processing procedures described in the embodiments may be rearranged as long as they do not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be realized in 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 be stored in any suitable storage medium such as random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or other appropriate storage medium.

[0127] Furthermore, notification of information is not limited to the embodiments described herein and may be performed by other methods. For example, notification of information may be performed by physical layer signaling (e.g., DCI, UCI (Uplink Control Information)), higher layer signaling (e.g., RRC signaling, MAC signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or combinations thereof. Information notified by higher layer signaling may be called configuration information. Information notified by physical layer signaling may be called control information. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.

[0128] Each aspect / embodiment described herein may be applied to at least one of systems utilizing LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR, W-CDMA®, GSM®, CDMA2000, UMB (Ultra Mobile Broadband), IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi®), IEEE 802.16 (WiMAX®), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth®, and other appropriate systems, as well as next-generation systems extended based thereon. Furthermore, multiple systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A and 5G).

[0129] The processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described herein may be reordered, provided they are consistent with each other. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.

[0130] In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one of the other network nodes (for example, an MME (Mobility Management Entity) or an S-GW (Serving Gateway), but not limited to these). Although the above example illustrates a case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

[0131] The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.

[0132] Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.

[0133] The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).

[0134] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0135] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technologies (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technologies (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0136] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0137] Furthermore, terms used 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 the channel and symbol may be a signal (signaling). Also, the signal may be a message. Also, CC may be called carrier frequency, cell, frequency carrier, etc.

[0138] The terms “system” and “network” as used in this disclosure are interchangeable.

[0139] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a given value, or other corresponding information. For example, wireless resources may be indicated by an index.

[0140] The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0141] In this disclosure, terms such as "Base Station (BS)", "wireless base station", "base station equipment", "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.

[0142] A base station can house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of ​​the base station can be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms “cell” or “sector” refer to part or all of the coverage area of ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0143] In this disclosure, the transmission of information by a base station to a terminal may be interpreted as the base station instructing the terminal to perform control or operation based on the information.

[0144] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0145] 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 several other appropriate terms.

[0146] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may also be a device mounted on a mobile body, the mobile body itself, etc. The mobile body refers to a movable object, and its speed of movement is arbitrary. This also includes the case when the mobile body is stationary. The mobile body includes, but is not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and items mounted on them. The mobile body may also be a mobile body that moves autonomously based on operation commands. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Furthermore, at least one of the base station and the mobile station may include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0147] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.

[0148] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the same functions as the user terminal described above.

[0149] As used in this disclosure, the terms “determining” and “determining” may encompass a wide variety of actions. “Determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, or inquiring (e.g., searching in a table, database, or other data structure), or ascertaining. “Determining” may also include receiving (e.g., receiving information), transmitting (e.g., sending information), inputting, outputting, or accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."

[0150] The terms “connected,” “coupled,” and any variations thereof mean 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” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be reinterpreted as “access.” As used in this disclosure, two elements may be considered to be “connected” or “coupled” with each other using at least one of one or more wires, cables, and printed electrical connections, and, in some non-limiting and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, and optical (both visible and invisible) domain.

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

[0152] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

[0153] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, references to the first and second elements do not imply that only two elements may be employed, or that the first element must precede the second element in any way.

[0154] In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.

[0155] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0156] A wireless frame may consist of one or more frames in the time domain. Each of these frames in the time domain may be called a subframe. A subframe may further consist 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.

[0157] Numerical logic may be communication parameters applied to at least one of the transmission and reception of a signal or channel. Numerical logic may include, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, and specific windowing processes performed by the transceiver in the time domain.

[0158] A slot may consist of one or more symbols in the time domain (such as OFDM symbols or SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols). A slot may also be a time unit based on neurology.

[0159] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. Minislots may also be called subslots. Minislots may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called a PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called a PDSCH (or PUSCH) mapping type B.

[0160] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Different names may be used for each of these terms.

[0161] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. In other words, at least one of a subframe and a TTI may be a subframe in existing LTE (1 millisecond [ms]), a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0162] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, the base station schedules each terminal 20 to allocate wireless resources (such as the frequency bandwidth and transmission power available to each terminal 20) in TTI units. However, the definition of TTI is not limited to this.

[0163] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the actual time interval (e.g., number of symbols) in which the transport block, code block, code word, etc. are mapped may be shorter than the TTI.

[0164] Furthermore, if one slot or one mini-slot is referred to as a TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit for scheduling. In addition, the number of slots (number of mini-slots) that constitute this minimum time unit for scheduling may be controlled.

[0165] A TTI with a time length of 1 ms may be called a normal TTI (TTI in LTE Release 8-12), a normal TTI, a long TTI, a normal subframe, a long subframe, a slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a mini slot, a sub slot, a slot, etc.

[0166] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

[0167] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.

[0168] Furthermore, the time domain of the RB may contain one or more symbols and may be the length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc., may each consist of one or more resource blocks.

[0169] One or more RBs may also be called a Physical RB (PRB), Subcarrier Group (SCG), Resource Element Group (REG), PRB pair, RB pair, etc.

[0170] Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.

[0171] A Bandwidth Part (BWP), also known as a partial bandwidth, may represent a subset of consecutive common RBs (Routing Bands) for a given neurology in a given carrier. Here, the common RBs may be identified by an index of RBs relative to a common reference point of the carrier. PRBs may be defined and numbered within a given BWP.

[0172] A BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be set within a single carrier for a UE.

[0173] At least one of the configured BWPs may be active, and the UE does not need to assume that it will transmit or receive a predetermined signal / channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be read as "BWP".

[0174] The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative. For example, the number of subframes included in a wireless frame, the number of slots per subframe or wireless 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, and the number of symbols, symbol length, and cyclic prefix (CP) length within the TTI can be varied in various ways.

[0175] In this disclosure, if articles are added by translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

[0176] In this 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 "combine" may be interpreted similarly to "different."

[0177] In this disclosure, the term "to do B in accordance with A" may also mean "to do B based on A".

[0178] Each aspect / embodiment described in this disclosure may be used individually, in combination, or switched between as needed during implementation. Furthermore, notification of specific information (e.g., notification that "X is") is not limited to explicit notification, but may also be implicit (e.g., by not providing such notification).

[0179] Although the present disclosure has been described in detail above, it will be 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 intent and scope of the present disclosure as defined by the claims. Therefore, the descriptions in the present disclosure are illustrative and not intended to be restrictive in any way.

[0180] This patent application claims priority based on Japanese Patent Application No. 2024-180389, filed on 15 October 2024, and the entire contents of Japanese Patent Application No. 2024-180389 are incorporated herein by reference.

[0181] 10 Base station 110 Transmitting unit 120 Receiving unit 130 Setting unit 140 Control unit 20 Terminal 210 Transmitting unit 220 Receiving unit 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Front wheel 2008 Rear wheel 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 Rotation speed 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 Driver assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (I / O port)

Claims

1. A terminal comprising: a transmitting unit that transmits a signal requesting the recovery of a wireless link failure or beam failure; a receiving unit that receives a predetermined response to the request; and a control unit that performs predetermined monitoring based on the timing of the recovery.

2. The terminal according to claim 1, wherein the control unit monitors the low-power wake-up signal while the recovery is being performed.

3. The terminal according to claim 1, wherein the control unit performs monitoring of the physical downlink control channel while the recovery is being performed.

4. The terminal according to claim 1, wherein the control unit performs monitoring of the low-power wake-up signal after the recovery is completed.

5. The terminal according to claim 1, wherein the control unit performs monitoring of the physical downlink control channel after the recovery is completed.

6. A communication method performed by a terminal, comprising the steps of: transmitting a signal requesting the recovery of a wireless link failure or beam failure; receiving a predetermined response to the request; and performing predetermined monitoring based on the timing of the recovery.

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