Terminal, wireless communication method, base station and system

Abstract

The present invention properly detects beam failure. A terminal according to one embodiment of the present disclosure has: a control unit that, if a set of reference signal (RS) indices, which correspond to a resource for beam failure detection (BFD), is not established by higher layer signaling and a specific parameter is established, follows a specific rule to select up to a prescribed number of control resource sets (COntrol REsource SET (CORESET)) for deciding the RS indices to be included in the set; and a reception unit for evaluating wireless link quality on the basis of the RS corresponding to the RS indices.

Description

Terminal, wireless communication method and base station

[0001] The present disclosure relates to a terminal, a wireless communication method, and a base station in a next-generation mobile communication system.

[0002] Long Term Evolution (LTE) has been specified for the Universal Mobile Telecommunications System (UMTS) network with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). Also, LTE-Advanced (3GPP Rel. 10-14) has been specified with the aim of achieving higher capacity and more advanced features than LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

[0003] Successor systems to LTE (e.g., 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 or later, etc.) are also being considered.

[0004] 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010

[0005] In future wireless communication systems (e.g., NR), it is being considered to implement a procedure for detecting beam failure and switching to another beam (which may also be called a Beam Failure Recovery (BFR) procedure, BFR, etc.).

[0006] For BFR, the UE detects beam failure using the configured reference signal resources. On the other hand, if the resources are not configured, the UE uses up to two reference signal indices corresponding to the Transmission Configuration Indication (TCI) state (TCI-state) of the control resource set (CORESET) as the set of indices corresponding to the resources.

[0007] Therefore, if the above resources are not configured for a UE and more than two CORESETs are configured, the UE needs to determine up to two indices to include in the set from the more than two indices corresponding to these CORESETs.

[0008] However, there has been little research into how to select the indexes to include in the set in such cases. Unless this is clearly defined, beam obstructions cannot be detected properly, which could result in a decrease in communication throughput.

[0009] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, and a base station that can appropriately detect beam obstructions.

[0010] A terminal according to one aspect of the present disclosure includes a control unit that, when a set of Reference Signal (RS) indices corresponding to resources for Beam Failure Detection (BFD) is not set by higher layer signaling and a specific parameter is set, selects up to a predetermined number of control resource sets (CONTROLLER REsource SETs (CORESETs)) for determining RS indices to be included in the set according to a specific rule, and a receiving unit that evaluates radio link quality based on the RSs corresponding to the RS indices.

[0011] According to one aspect of the present disclosure, beam obstructions can be detected appropriately.

[0012] Fig. 1 is a diagram showing an example of a beam failure recovery procedure in Rel. 15 NR. Fig. 2 is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment. Fig. 3 is a diagram showing an example of a configuration of a base station according to an embodiment. Fig. 4 is a diagram showing an example of a configuration of a user terminal according to an embodiment. Fig. 5 is a diagram showing an example of a hardware configuration of a base station and a user terminal according to an embodiment.

[0013] (TCI, spatial relationship, QCL) In NR, it is considered to control the reception processing (e.g., at least one of reception, demapping, demodulation, and decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, and encoding) in a UE of at least one of a signal and a channel (referred to as a signal / channel) based on a transmission configuration indication state (TCI state).

[0014] The TCI state may represent that which is applied to a downlink signal / channel, and the equivalent of the TCI state that is applied to an uplink signal / channel may be expressed as a spatial relation.

[0015] The TCI state is information about the Quasi-Co-Location (QCL) of signals / channels, and may also be called spatial reception parameters, spatial relation information, etc. The TCI state may be configured in the UE for each channel or signal.

[0016] The QCL is an index indicating the statistical properties of signals / channels. For example, if a signal / channel has a QCL relationship with another signal / channel, it may mean that it can be assumed that at least one of a Doppler shift, a Doppler spread, an average delay, a delay spread, and a spatial parameter (e.g., a spatial Rx parameter) is the same between these different signals / channels (i.e., the signals / channels have a QCL with respect to at least one of these).

[0017] The spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be identified based on a spatial QCL. The QCL (or at least one element of the QCL) in the present disclosure may be replaced with sQCL (spatial QCL).

[0018] A plurality of types (QCL types) of QCL may be defined. For example, four QCL types A to D may be provided, each having different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may be referred to as QCL parameters) are as follows: QCL type A (QCL-A): Doppler shift, Doppler spread, mean delay, and delay spread QCL type B (QCL-B): Doppler shift and Doppler spread QCL type C (QCL-C): Doppler shift and mean delay QCL type D (QCL-D): Spatial reception parameters.

[0019] The UE's assumption that a Control Resource Set (CORESET), channel, or reference signal has a specific QCL (e.g., QCL type D) relationship with another CORESET, channel, or reference signal may be referred to as a QCL assumption.

[0020] The UE may determine at least one of a transmit beam (Tx beam) and a receive beam (Rx beam) for a signal / channel based on the TCI condition or QCL assumption of the signal / channel.

[0021] The TCI state may be, for example, information about the QCL between the channel of interest (in other words, the Reference Signal (RS) for that channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by higher layer signaling, physical layer signaling, or a combination thereof.

[0022] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

[0023] The MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0024] The physical layer signaling may be, for example, Downlink Control Information (DCI).

[0025] The channel / signal to which the TCI state is applied may be called a target channel / reference signal (target channel / RS), or simply a target, and the other signal may be called a reference reference signal (reference RS), a source RS, or simply a reference.

[0026] The channel for which the TCI state or spatial relationship is set (specified) may be, for example, at least one of a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), a physical uplink shared channel (PUSCH), and a physical uplink control channel (PUCCH).

[0027] Furthermore, the RS that has a QCL relationship with the channel may be at least one of, for example, a synchronization signal block (SSB), a channel state information reference signal (CSI-RS), a sounding reference signal (SRS), a tracking CSI-RS (also called a tracking reference signal (TRS)), a QCL detection reference signal (also called a QRS), a demodulation reference signal (DMRS), etc.

[0028] An SSB is a signal block including at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). An SSB may also be referred to as an SS / PBCH block.

[0029] An RS of QCL type X in a TCI state may refer to an RS that has a QCL type X relationship with a certain channel / signal (DMRS), and this RS may be called a QCL source of QCL type X in the TCI state.

[0030] (BFR) In NR, the use of beamforming for communication is being considered. Also, in order to suppress the occurrence of radio link failure (RLF), when the quality of a specific beam deteriorates, a procedure for switching to another beam (which may be called beam recovery (BR), beam failure recovery (BFR), L1 / L2 (Layer 1 / Layer 2) beam recovery, etc.) is being considered. The BFR procedure may also be simply called BFR.

[0031] Note that a beam failure in this disclosure may also be referred to as a link failure.

[0032] 1 is a diagram showing an example of a beam failure recovery procedure in Rel. 15 NR. The number of beams and other information is merely an example and is not limited to this.

[0033] In the initial state (step S101) of Fig. 1, the UE performs measurement based on RS resources transmitted using two beams. The RS may be at least one of an SSB and a CSI-RS. The RS measured in step S101 may be referred to as an RS for beam failure detection (BFD-RS: Beam Failure Detection RS), or the like. Beam failure detection may simply be referred to as failure detection.

[0034] In step S102, the UE cannot detect the BFD-RS (or the reception quality of the RS deteriorates) due to interference with the radio waves from the base station. Such interference can occur due to, for example, obstacles, fading, interference, etc. between the UE and the base station.

[0035] The UE detects beam failure when a predetermined condition is satisfied. The UE may detect the occurrence of beam failure, for example, when the block error rate (BLER) is less than a threshold for all configured BFD-RSs. When the occurrence of beam failure is detected, the lower layer (physical (PHY) layer) of the UE may notify (indicate) the upper layer (MAC layer) of the beam failure instance.

[0036] The criteria for determination are not limited to BLER, but may be Layer 1 Reference Signal Received Power (L1-RSRP) in the physical layer. RSRP in the present disclosure may be replaced with RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), or other information related to power or quality.

[0037] Also, beam failure detection may be performed based on PDCCH, etc., instead of or in addition to RS measurements. BFD-RS may be expected to be the DMRS and QCL of the PDCCH monitored by the UE.

[0038] Information about BFD-RS (e.g., RS index, resource, number, number of ports, precoding, etc.), information about beam failure detection (BFD) (e.g., the above-mentioned threshold), etc. may be configured (notified) to the UE using higher layer signaling, etc. Information about BFD-RS may be interchangeably read as information about BFD resources, information about BFD-RS resources, etc.

[0039] The MAC layer of the UE may start a predetermined timer (which may be called a beam failure detection timer) when it receives a beam failure instance notification from the PHY layer of the UE. If the MAC layer of the UE receives a certain number of beam failure instance notifications (e.g., a "beamFailureInstanceMaxCount" configured in RRC) before the timer expires, the MAC layer of the UE may trigger a BFR (e.g., start one of the random access procedures described below).

[0040] The base station may determine that the UE has detected a beam failure if there is no notification from the UE or if it receives a predetermined signal (beam recovery request in step S104) from the UE.

[0041] In step S103, the UE starts searching for a new candidate beam to be used for new communication in order to recover the beam. The UE may select a new candidate beam corresponding to a predetermined RS by measuring the RS. The RS measured in step S103 may be called an RS for identifying a new candidate beam (NCBI-RS: New Candidate Beam Identification RS), CBI-RS, CB-RS (Candidate Beam RS), etc. The NCBI-RS may be the same as or different from the BFD-RS. The new candidate beam may simply be called a candidate beam, a new beam, etc.

[0042] The UE may determine a beam corresponding to an RS that satisfies a predetermined condition as a new candidate beam. The UE may determine a new candidate beam, for example, based on an RS among the configured NCBI-RSs whose L1-RSRP exceeds a threshold. Note that the criteria for determination are not limited to L1-RSRP. The L1-RSRP related to SSB may be referred to as SS-RSRP. The L1-RSRP related to CSI-RS may be referred to as CSI-RSRP.

[0043] Information about the NCBI-RS (e.g., RS resources, number of ports, precoding, etc.), information about the new candidate beam identification (NCBI) (e.g., the above-mentioned threshold), etc. may be configured (notified) to the UE using higher layer signaling, etc. The information about the NCBI-RS may be acquired based on information about the BFD-RS. The information about the NCBI-RS may be referred to as information about NBCI resources, etc.

[0044] Note that BFD-RS, NCBI-RS, etc. may be read as Radio Link Monitoring RS (RLM-RS).

[0045] In step S104, the UE that has identified the new candidate beam transmits a beam failure recovery request (BFRQ). The beam recovery request may be referred to as a beam recovery request signal, a beam failure recovery request signal, or the like.

[0046] The BFRQ may be transmitted using at least one of the PUCCH, the PRACH, the PUSCH, and a configured grant PUSCH. The UE may transmit a preamble (also referred to as an RA preamble, PRACH, etc.) as the BFRQ using a PRACH resource.

[0047] Information regarding the correspondence between the detected DL-RS (beam) and the PRACH resource (RA preamble) may be configured in the UE by, for example, higher layer signaling (such as RRC signaling).

[0048] The BFRQ may include information of the new candidate beam identified in step S103. A resource for the BFRQ may be associated with the new candidate beam. The beam information may be notified using a beam index (BI), a port index of a predetermined reference signal, a resource index (e.g., a CSI-RS resource indicator (CRI), an SSB resource indicator (SSBRI)), or the like.

[0049] In step S105, the base station that detected the BFRQ transmits a response signal (which may be referred to as a gNB response, etc.) to the BFRQ from the UE. The response signal may include reconfiguration information (e.g., DL-RS resource configuration information) for one or more beams. The UE may determine at least one of a transmission beam and a reception beam to be used based on the beam reconfiguration information.

[0050] The response signal may be transmitted, for example, in the UE common search space of the PDCCH. The response signal may be signaled using a DCI (PDCCH) with a Cyclic Redundancy Check (CRC) scrambled by the UE's identifier (e.g., Cell-Radio RNTI (C-RNTI)). The UE may determine that contention resolution is successful if it receives a PDCCH corresponding to its own C-RNTI.

[0051] The UE may monitor the response signal based on at least one of a CORESET for BFR and a search space set for BFR.

[0052] Regarding the processing of step S105, a period for the UE to monitor a response from a base station (e.g., a gNB) to the BFRQ may be set. This period may be referred to as, for example, a gNB response window, a gNB window, a beam recovery request response window, etc. If no gNB response is detected within this window period, the UE may retransmit the BFRQ.

[0053] In step S106, the UE may transmit a message indicating that the beam reconfiguration is complete to the base station. The message may be transmitted, for example, via the PUCCH or the PUSCH.

[0054] A beam recovery success (BR success) may indicate, for example, that step S106 has been reached, whereas a beam recovery failure (BR failure) may indicate, for example, that a predetermined number of BFRQ transmissions have been made or that a beam-failure-recovery-timer has expired.

[0055] Note that the numbers of these steps are for illustrative purposes only, and multiple steps may be combined or the order may be reversed. Furthermore, whether to perform BFR may be configured in the UE using higher layer signaling.

[0056] In Rel. 15 / 16 NR, a base station can configure up to two BFD resources per BWP to a UE using higher layer signaling. For example, the UE may be provided with resources related to the beam failure purpose in failure detection resource configuration information (e.g., higher layer parameters "failureDetectionResourcesToAddModList" and "failureDetectionResources"; hereinafter, referred to as "failureDetectionResources").

[0057] For example, for each BWP of a serving cell, the UE may be provided with a set of periodic (P)-CSI-RS resource configuration indexes (e.g., non-zero power CSI-RS resource IDs) by the resource configuration information for failure detection. The set may be a set q ０ bar (where q ０ The bar is "q ０ "), or may be called an index set. Hereinafter, this set will be referred to simply as "set q ０ " is written as ".

[0058] A set of P-CSI-RS resources q explicitly provided by the resource configuration information for failure detection ０ may be referred to as an explicit BFD-RS, an explicit BFD-RS resource, etc.

[0059] The UE selects the set q ０ may perform at least one of radio link quality evaluation, channel measurement, L1-RSRP measurement, etc. based on the RS resource corresponding to the index included in

[0060] For example, the physical layer in the UE may be configured to ｏｕｔ，ＬＲ , and a set of resource configurations q ０ The wireless link quality is evaluated according to the set q ０ In contrast, the UE may evaluate the radio link quality according to a P-CSI-RS resource configuration that is quasi-co-located (QCLed) with the DM-RS of the PDCCH reception monitored by the UE, or an SS / PBCH block on the PCell or PSCell that is quasi-co-located with the DM-RS of the PDCCH reception monitored by the UE.

[0061] In other words, regardless of whether the BFD-RS is explicit or implicit, the BFD-RS may be QCL'd with the PDCCH.

[0062] In the present disclosure, provision of the above-mentioned upper layer parameters (fault detection resource configuration information) indicating information on indexes corresponding to BFD resources may be interpreted as configuring BFD resources, configuring BFD-RS, etc. In the present disclosure, the set q of BFD resources, periodic CSI-RS resource configuration indexes, or SSB indexes ０ , BFD-RS, etc. may be read interchangeably.

[0063] On the other hand, in Rel. 15 / 16 NR, if the UE is not configured with resources for BFD, it assigns the index of the periodic CSI-RS resource configuration, which is the same value as the RS index in the RS set indicated by the TCI state of the CORESET used to monitor the PDCCH, to the set q ０ It is stipulated that the decision will be made to include

[0064] For example, the UE may set q for one BWP of the serving cell by the failure detection resource configuration information (failureDetectionResources). ０ If the UE is not provided with a P-CSI-RS resource configuration index that has the same value as the RS index in the RS set indicated by the TCI state (“TCI-State”) for the corresponding CORESET that the UE uses to monitor the PDCCH, the P-CSI-RS resource configuration index in the set q ０ Decide to include it in

[0065] Set q determined when BFD resources are not set ０ may be referred to as an implicit BFD-RS, an implicit BFD-RS resource, etc. In the present disclosure, the implicit BFD-RS is a set q ０ In the present disclosure, the BFR-RS may refer to the BFR-RS determined by the UE for the BWP of the serving cell that is not provided with the set q ０ The fact that the set q is not provided by the resource configuration information for failure detection for a certain BWP of a certain serving cell ０ This may also be interpreted as meaning that the BWP of the serving cell is not provided, that BFD resources are not configured for the serving cell, etc.

[0066] Note that if there are two RS indices in one TCI state, then the set q ０ contains the RS indexes for which QCL type D is configured for the corresponding TCI state. ０ The UE expects that the set q ０ Assume a single port RS in the

[0067] (Multi-TRP) In NR, one or more transmission / reception points (TRPs) (multi-TRPs (MTRPs)) are considered to perform DL transmission to a UE. It is also considered that a UE performs UL transmission to one or more TRPs.

[0068] If the UE is provided with no CORESET pool index (higher layer parameter CORESETPoolIndex) or with a CORESET pool index value = 0 for one or more first CORESETs and with a CORESET pool index value = 1 for one or more second CORESETs in the active downlink Bandwidth Part (BWP) of a serving cell, it may assume that Multi-DCI based Multi-TRP is used (or controlled based on).

[0069] As described above, when more than two CORESETs are configured for a UE and the failure detection resource configuration information is used to configure the set q ０ If the UE is not provided with a CORESET, it selects a set q from the more than two RS indices corresponding to these CORESETs. ０ It is necessary to determine up to two indices to be included in the BWP. There are cases where more than two (e.g., three) CORESETs are configured for a UE per BWP. For example, when Multi-DCI based Multi-TRP is used, there are cases where a total of five CORESETs are configured.

[0070] However, how can we determine the set q in this case? ０ The selection of the indexes to be included in the set q is not yet under consideration. ０ If the BFD-RS selection method is not provided, the previous Rel. 15 / 16 specifications stipulate that up to two BFD-RSs are selected based on the TCI status of CORESET, but there is no specification for the selection method, so it is up to the UE implementation. If the BFD-RS selection method is not clearly specified, beam obstruction cannot be detected properly, and communication throughput may decrease.

[0071] Therefore, the present inventors have conceived a method for determining a reference signal index for appropriately detecting beam obstructions.

[0072] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0073] In the present disclosure, "A / B" may also mean "at least one of A and B."

[0074] In the present disclosure, the terms activate, deactivate, indicate, select, configure, update, determine, etc. may be read interchangeably.

[0075] In the present disclosure, RRC, RRC parameters, RRC messages, higher layer parameters, information elements (IEs), and configurations may be interchangeable. In the present disclosure, MAC CE, update commands, and activation / deactivation commands may be interchangeable. In the present disclosure, support, control, controllable, operate, and operable may be interchangeable.

[0076] Additionally, in the present disclosure, the terms sequence, list, set, group, and group may be read interchangeably.

[0077] In the present disclosure, the terms panel, beam, panel group, beam group, Uplink (UL) transmitting entity, TRP, spatial relationship information (SRI), spatial relationship, control resource set (CONTROLLER RESOLUTION SET (CORESET)), Physical Downlink Shared Channel (PDSCH), codeword, base station, predetermined antenna port (e.g., Demodulation Reference Signal (DMRS) port), predetermined antenna port group (e.g., DMRS port group), predetermined group (e.g., Code Division Multiplexing (CDM) group, predetermined reference signal group, CORESET group), predetermined resource (e.g., predetermined reference signal resource), predetermined resource set (e.g., predetermined reference signal resource set), CORESET pool, PUCCH group (PUCCH resource group), spatial relationship group, downlink TCI state (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, ... state), etc. may be read interchangeably.

[0078] The panel may be associated with at least one of a group index of an SSB / CSI-RS group, a group index of a group-based beam report, and a group index of an SSB / CSI-RS group for group-based beam reporting.

[0079] Furthermore, the panel identifier (ID) and the panel may be interchangeable. That is, the TRP ID and the TRP, the CORESET group ID and the CORESET group, etc. may be interchangeable.

[0080] In the present disclosure, the terms index, identifier (ID), indicator, resource ID, etc. may be interchangeable. In the present disclosure, the terms sequence, list, set, group, cluster, subset, etc. may be interchangeable.

[0081] In this disclosure, a single PDCCH may be assumed to be supported when multiple TRPs utilize an ideal backhaul, and multiple PDCCHs may be assumed to be supported when multiple TRPs utilize a non-ideal backhaul.

[0082] The ideal backhaul may be called DMRS port group type 1, reference signal related group type 1, antenna port group type 1, CORESET pool type 1, etc. The non-ideal backhaul may be called DMRS port group type 2, reference signal related group type 2, antenna port group type 2, CORESET pool type 2, etc. The names are not limited to these.

[0083] In the present disclosure, multi-TRP, multi-TRP system, multi-TRP transmission, and multi-PDSCH may be read interchangeably.

[0084] In the present disclosure, single DCI (sDCI), single PDCCH, multi-TRP system based on single DCI, sDCI-based MTRP, and activation of two TCI states on at least one TCI codepoint may be read interchangeably.

[0085] In the present disclosure, multi-DCI (mDCI), multi-PDCCH, multi-TRP system based on multi-DCI, mDCI-based MTRP, and setting two CORESET pool indices or CORESET pool index = 1 (or a value greater than or equal to 1) may be read interchangeably.

[0086] In the present disclosure, the terms "first TRP," "TRP1," "first CORESET," and "CORESET with no CORESET pool index or with a CORESET pool index value of 0" may be interchangeable. Also, the term "first CORESET" may refer to one or more first CORESETs.

[0087] In the present disclosure, the terms "second TRP," "TRP2," "second CORESET," and "CORESET provided with a CORESET pool index value of 1" may be interchangeable. Also, the term "second CORESET" may refer to one or more second CORESETs.

[0088] In the following embodiments, the description will be given assuming that the number of implicit BFD-RSs is a maximum of two, but this is not limited to this. In the present disclosure, "two" may be interchangeably read as a plurality (for example, three or more). Furthermore, the following embodiments may or may not be limited to the case of multi-TRP.

[0089] (Wireless Communication Method) First Embodiment The first embodiment relates to the determination of an implicit BFD-RS.

[0090] In the first embodiment, the UE selects a set q for a certain BWP of a certain serving cell by failure detection resource configuration information (failureDetectionResources). ０ If not provided with a set q, the UE shall select the CSI-RS provided for the active TCI state for PDCCH reception in the CORESET associated with the search space set in the order of the search space sets from the smallest monitoring period. ０ The UE may determine the index of the determined CSI-RS as the CSI-RS for the set q ０ It may be determined to include

[0091] Also, if more than one CORESET is associated with multiple search space sets having the same monitoring period, the UE may determine the CSI-RS in the order of the CORESETs from the highest CORESET index.

[0092] In other words, the UE selects (determines) two CORESETs for the implicit BFD-RS from among the CORESETs with active TCI states, prioritizing first the smallest monitoring period of the corresponding search space set and second the size of the CORESET ID, and then assigns the indexes of the RSs identified based on each CORESET to a set q ０ The UE may, for example, decide to include the indices of the RSs provided by the active TCI states of each CORESET in the set q ０ may be included in.

[0093] [Modification of the First Embodiment] The UE selects a set q for a certain BWP of a certain serving cell according to the failure detection resource configuration information. ０ If no CORESET is provided, two CORESETs that satisfy one of the following rules or a combination thereof are selected from the set of CORESETs, and the indexes of the RSs identified based on each CORESET are included in the set q ０ It may be decided to include in the list: CORESETs with / without a configured TCI state, CORESETs with / without an active TCI state, CORESETs that correspond / do not correspond to a specific CORESET pool index (e.g., CORESET pool index = 0, 1), CORESETs whose associated search space set has the maximum / minimum monitoring period, CORESETs with the maximum / minimum CORESET ID, CORESETs with the maximum / minimum CSI-RS (Reference RS) period corresponding to the TCI state, CORESETs whose associated search space set is a specific search space set (e.g., common search space set, UE-specific search space set), CORESETs in (monitored at) the latest monitoring slot, A CORESET corresponding to the first CORESET / second CORESET.

[0094] The priority order of these rules may be any order (the CORESET may be determined by applying these rules in any order). For example, when there are multiple CORESETs that satisfy a certain rule, the UE may select one or more CORESETs from these CORESETs based on another rule.

[0095] In the present disclosure, "minimum" may be read interchangeably as "maximum," "highest," "lowest," "a specific value," "i-th (i is an integer, for example, 1, 2, ...)," "smallest," "largest," "smallest two," "largest two," etc. In the present disclosure, "small" and "large" may be read interchangeably as "largest."

[0096] For example, the UE may select a set q for a certain BWP of a certain serving cell according to the resource configuration information for failure detection. ０ If not provided with CSI-RS, the UE shall select the CSI-RS provided for the active TCI state for PDCCH reception in the CORESET with the smallest CORESET ID in the latest monitoring slot from set q ０ It may be determined as the CSI-RS for the

[0097] In addition, the UE may set q for a certain BWP of a certain serving cell according to the resource configuration information for failure detection. ０ If not provided with CSI-RS, the UE shall select the CSI-RS provided for the active TCI state for PDCCH reception in the CORESET with the smallest CORESET ID from set q ０ It may be determined as the CSI-RS for the

[0098] In the above-mentioned selection of the CORESET, for example, by prioritizing the smallest CORESET ID, the BFD of CORESET #0, which is considered to be the most important, can be preferably implemented.

[0099] By prioritizing the length of the monitoring period, it is possible to preferably detect a failure of a PDCCH with a long period, in which the occurrence of a failure is difficult to notice, whereas by prioritizing the short monitoring period, it is possible to preferably detect a failure of a PDCCH for low latency.

[0100] By prioritizing the length of the CSI-RS period, BFD of the PDCCH, which is considered to be of relatively poor quality, can be preferably performed. On the other hand, by prioritizing the short CSI-RS period, more accurate (highly reliable) BFD can be preferably performed.

[0101] By giving priority to the CORESET corresponding to the common search space set, BFD of the PDCCH, which is generally considered to be more important, can be preferably performed. On the other hand, by giving priority to the CORESET corresponding to the UE-specific search space set, BFD of the PDCCH, which is important for scheduling, such as the PDSCH and PUSCH, including the TCI status indication MAC CE, can be preferably performed.

[0102] In addition, the implicit BFD-RS may be determined for each CORESET pool index. In other words, the UE selects two CORESETs from the first CORESET based on one of the above rules or a combination of these rules to determine the implicit BFD-RS corresponding to the CORESET pool index=0, and then determines the index of the RS identified based on each CORESET by dividing the index of the RS into the set q for the CORESET pool index=0. ０ The UE may also determine to include the implicit BFD-RSs corresponding to the CORESET pool index=1 in the second CORESET based on any one of the above rules or a combination thereof, and determine the indexes of the RSs identified based on each CORESET in the set q for the CORESET pool index=1. ０ You may decide to include it in

[0103] Regarding the restriction on the number of BFD-RSs (maximum 2 in Rel. 15; further restricted in Rel. 16 by the UE capability information (e.g., maxTotalResourcesForOneFreqRange-r16) described in the second embodiment), the UE may assume that the number of restricted BFD-RSs is the number per CORESET pool index, or the total number for all CORESET pool indices.

[0104] The implicit BFD-RS may be determined from the CORESET with CORESET ID=0 (CORESET#0), or may be determined from the CORESET excluding CORESET#0.

[0105] In addition, set q ０ Regarding the index of the RS included in the above, the RS may be any RS (for example, SSB / CSI-RS / TRS, etc.) or may be limited to a specific RS (for example, may be limited to CSI-RS / TRS). In other words, the CSI-RS in the present disclosure may be interchangeably read as at least one of the any RS, the specific RS, etc.

[0106] In addition, when two RSs in the TCI state for a CORESET corresponding to a certain CORESET ID are configured (for example, an RS for QCL type D and an RS for QCL type A), the UE sets the index of one RS (for example, the RS for QCL type D) as q ０ or the indices of both RSs can be included in the set q ０ may be included in.

[0107] According to the first embodiment described above, when BFD resources are not configured, a BFD-RS can be determined based on an appropriate CORESET. If the RLM and BFR handle link failures in the same way, link recovery can be made redundant using the same CORESET. If the RLM and BFR handle link failures differently, link failures that are not covered by the RLM can be covered by the BFR.

[0108] Second Embodiment The second embodiment relates to conditions for applying the implicit BFD-RS decision in the first embodiment described above.

[0109] The UE may perform the determination of the implicit BFD-RS in the first embodiment that satisfies the conditions (the implicit BFD-RS may be determined based on the determination method of the first embodiment) when any one or more of the following conditions are met: - Specific parameters are set by higher layer signaling, - Specific UE capability information is reported (or the UE supports the UE capability corresponding to the information), - The BFD-RS is used for BFR for the PCell / PSCell, - The BFD-RS is used for BFR for the SCell.

[0110] If the specific parameters are not configured, the UE may determine the implicit BFD-RS not based on the first embodiment but, for example, according to Rel. 15. The specific parameters may be information for configuring a CORESET with a CORESET pool index of 1, information related to multi-TRP, information for configuring a BFD-RS determination method, any RRC parameters for a specific release (e.g., Rel. 16, Rel. 17), etc.

[0111] For example, the information for setting the BFR-RS determination method may correspond to information indicating that the BFR-RS determination method shown in the first embodiment is enabled (information whose value indicates "enable"; may also be called an enabler).

[0112] The above-mentioned specific parameters may be set, for example, in beam failure recovery configuration information, for example, in beam failure recovery configuration information (e.g., BeamFailureRecoveryConfig) for a special cell (SpCell, including a primary cell (PCell) and a primary secondary cell (PSCell)), or in beam failure recovery configuration information (e.g., BeamFailureRecoverySCellConfig) for a secondary cell (SCell).

[0113] The specific UE capability information may be UE capability information for a specific release (e.g., Rel. 16, Rel. 17). For example, the specific UE capability information may be at least one of the following: - Information indicating whether the UE supports multi-DCI-based multi-TRP (e.g., multiDCI-MultiTRP-r16), - Information indicating the maximum number of configured CORESETs per BWP per cell (e.g., maxNumberCORESET-r16), - Information indicating the maximum number of configured CORESETs per CORESET pool index per BWP per cell (e.g., maxNumberCORESETPerPoolIndex-r16), - Information indicating the maximum total number of SSB / CSI-RS / CSI-IM resources supported by the UE for beam management, path loss measurement, BFD, RLM, new beam identification, etc. in one frequency range (e.g., maxTotalResourcesForOneFreqRange-r16), Information indicating the maximum value of the total number of SSB / CSI-RS / CSI-IM resources configured for measurements for L1-RSRP measurement, L1-SINR measurement, path loss measurement, BFD, RLM, new beam identification, etc. within one slot across all CCs in one frequency range (e.g., maxNumberResWithinSlotAcrossCC-OneFR-r16); Information indicating the maximum value of the total number of SSB / CSI-RS / CSI-IM resources configured for measurements for L1-RSRP measurement, L1-SINR measurement, path loss measurement, BFD, RLM, new beam identification, etc. across all CCs in one frequency range (e.g., maxNumberResAcrossCC-OneFR-r16); Information indicating the maximum total number of SSB / CSI-RS / CSI-IM resources supported by the UE for beam management, path loss measurement, BFD, RLM, new beam identification, etc. across multiple frequency ranges (e.g., both FR1 and FR2) (e.g., maxTotalResourcesForOneFreqRange-r16);- Information indicating the maximum value of the total number of SSB / CSI-RS / CSI-IM resources configured for measurements such as L1-RSRP measurement, L1-SINR measurement, path loss measurement, BFD, RLM, new beam identification, etc. within one slot across all CCs across multiple frequency ranges (e.g., maxNumberResWithinSlotAcrossCC-AcrossFR-r16); - Information indicating the maximum value of the total number of SSB / CSI-RS / CSI-IM resources configured for measurements such as L1-RSRP measurement, L1-SINR measurement, path loss measurement, BFD, RLM, new beam identification, etc. across all CCs across multiple frequency ranges (e.g., maxNumberResAcrossCC-AcrossFR-r16).

[0114] Note that the above "reporting specific UE capability information" may be read as "reporting UE capability information of a specific value." For example, this "UE capability information of a specific value" may be information (e.g., maxNumberCORESET-r16) indicating the maximum CORESET number set for each BWP for each cell having a specific value (e.g., 3 or more), or information (e.g., maxNumberCORESETPerPoolIndex-r16) indicating the maximum CORESET number set for each CORESET pool index for each BWP for each cell having a specific value (e.g., 3 or more).

[0115] According to the second embodiment described above, it is possible to use the implicit BFD-RS determination method of the first embodiment under appropriate conditions, and it is possible to prevent, for example, a Rel. 15 UE from erroneously using the implicit BFD-RS determination method of the first embodiment.

[0116] (Wireless Communication System) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0117] 2 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0118] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0119] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (Master Node (MN)), and the NR base station (gNB) is the secondary node (Secondary Node (SN)). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0120] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0121] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0122] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CCs) and dual connectivity (DC).

[0123] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

[0124] Furthermore, the user terminal 20 may perform communication using at least one of time division duplex (TDD) and frequency division duplex (FDD) in each CC.

[0125] The multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with the Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0126] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0127] The user terminal 20 may be a terminal that supports at least one of communication methods such as LTE, LTE-A, and 5G.

[0128] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the wireless communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0129] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (e.g., other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0130] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0131] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), or the like may be used as an uplink channel.

[0132] The PDSCH transmits user data, higher layer control information, a System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit a Master Information Block (MIB).

[0133] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

[0134] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as a UL grant, a UL DCI, etc. Note that the PDSCH may be replaced with DL data, and the PUSCH may be replaced with UL data.

[0135] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources for searching for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

[0136] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," "CORESET configuration," and the like in the present disclosure may be read interchangeably.

[0137] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0138] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0139] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

[0140] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as a reference signal.

[0141] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), or the like may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0142] (Base Station) Fig. 3 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0143] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0144] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0145] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0146] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0147] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be configured from a transmitting unit and a receiving unit. The transmitting unit may be configured from a transmission processing unit 1211 and an RF unit 122. The receiving unit may be configured from a reception processing unit 1212, the RF unit 122, and a measurement unit 123.

[0148] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0149] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0150] The transceiver 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0151] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0152] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0153] The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

[0154] On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

[0155] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0156] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0157] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0158] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0159] In addition, the transceiver unit 120 may not set a set of Reference Signal (RS) indices corresponding to resources for Beam Failure Detection (BFD) to the user terminal 20 by upper layer signaling, but may instead set specific parameters (or may transmit upper layer signaling for setting the specific parameters).

[0160] The control unit 110 may assume that the user terminal 20 selects up to a predetermined number of control resource sets (COntrol REsource SETs (CORESETs)) for determining RS indices to be included in the set according to a specific rule, and evaluates the radio link quality based on the RSs corresponding to the RS indices (RS indices associated with the selected CORESET).

[0161] (User Terminal) Fig. 4 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0162] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0163] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on common understanding in the technical field to which the present disclosure relates.

[0164] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 220.

[0165] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0166] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0167] The transmitting / receiving antenna 230 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0168] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0169] The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0170] The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0171] The transmitter / receiver unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0172] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and if not, it may not be necessary to perform DFT processing as the transmission processing.

[0173] The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

[0174] On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

[0175] The transceiver unit 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0176] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0177] The transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving unit 220 and the transmitting / receiving antenna 230.

[0178] In addition, when a set of Reference Signal (RS) indices corresponding to resources for Beam Failure Detection (BFD) is not set by higher layer signaling and specific parameters (parameters described in the second embodiment above) are set, the control unit 210 may select up to a predetermined number of control resource sets (COntrol REsource SETs (CORESETs)) for determining the RS indices to be included in the set according to specific rules (one or more rules described in the first embodiment above).

[0179] The transceiver unit 220 may evaluate the radio link quality based on the RS corresponding to the RS index.

[0180] The control unit 210 may further select up to the predetermined number of CORESETs for determining RS indices to be included in the set according to the specific rule when reporting specific capability information (UE capability information described in the second embodiment above).

[0181] The specific rule may be a rule that selects up to the predetermined number of CORESETs by first prioritizing the smallest monitoring period of the corresponding search space set and second prioritizing the size of the CORESET identifier.

[0182] The specific parameters may be included in beam failure recovery setting information and notified by the base station 10.

[0183] (Hardware Configuration) Note that the block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and 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 (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0184] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As described above, the implementation method of each is not particularly limited.

[0185] For example, a base station, a user terminal, 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. 5 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0186] In the present disclosure, the terms apparatus, circuit, device, section, unit, etc. may be used interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0187] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0188] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading specified software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0189] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transceiver unit 120 (220), etc. may be realized by the processor 1001.

[0190] 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. For example, the control unit 110 (210) may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be implemented in a similar manner.

[0191] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EEPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, cache, main memory, etc. The memory 1002 may store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0192] Storage 1003 is a computer-readable recording medium and may be composed of at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0193] 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, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0194] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a light emitting diode (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).

[0195] 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.

[0196] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using this hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0197] (Modifications) Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0198] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may 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.

[0199] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, Subcarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, specific filtering performed by a transceiver in the frequency domain, and specific windowing performed by a transceiver in the time domain.

[0200] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may also be a time unit based on numerology.

[0201] 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 (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0202] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0203] For example, one subframe may be referred to as a TTI, or 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 (for example, 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.

[0204] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0205] 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.

[0206] 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. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0207] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0208] 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 greater than or equal to 1 ms.

[0209] 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.

[0210] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI, each of which may be composed of one or more resource blocks.

[0211] In addition, one or more RBs may be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0212] 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.

[0213] 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 given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0214] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0215] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given channel / signal outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0216] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0217] 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 a predetermined index.

[0218] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (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.

[0219] 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.

[0220] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0221] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0222] 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 in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0223] Note that the physical layer signaling may be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be referred to as an RRC message, such as an RRC Connection Setup message or an RRC Connection Reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0224] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0225] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0226] 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.

[0227] 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), these wired and / or wireless technologies are included within the definition of transmission media.

[0228] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0229] In the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0230] In the present disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0231] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication service within that coverage.

[0232] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0233] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0234] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a wireless communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body 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). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0235] Furthermore, a base station in the present disclosure may be read as a user 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 user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0236] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0237] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc.), or a combination thereof.

[0238] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. 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.

[0239] Each aspect / embodiment described in the present disclosure may be a technology other than Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE The present invention may be applied to systems that use IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other appropriate wireless communication methods, or to next-generation systems that are based on these and are extended thereto. In addition, the present invention may be applied to a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0240] 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."

[0241] 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.

[0242] The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0243] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0244] Also, "determination" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "determination" may be considered to be "deciding" some action.

[0245] Furthermore, "judgment (decision)" may be read as "assuming," "expecting," "considering," or the like.

[0246] As used in this disclosure, 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."

[0247] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0248] 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."

[0249] 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.

[0250] 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.

[0251] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not impose any limiting meaning on the invention according to the present disclosure.

[0252] This application is based on Japanese Patent Application No. 2021-67264, filed on April 12, 2021, the contents of which are incorporated herein in their entirety.

Claims

1. A receiving unit that receives a zeroth value of a control resource set (COntrol REsource SET (CORESET)) pool index and a first value of a CORESET pool index different from the zeroth value by an upper layer parameter; In a Beam Failure Detection (BFD)-Reference Signal (RS) for PCell, PSCell, and SCell beam failures, when the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value and the set of RS resource indexes for BFD corresponding to the CORESET pool index of the first value are not configured by BFD resource configuration, an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the 0 value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value, and an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the first value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value. and a control unit for determining a set of RSs provided for an active TCI state for PDCCH reception in the ID as a set of RS resource indexes for BFD corresponding to the first value of CORESET pool index, A terminal in which the number of BFD-RSs limited by terminal capability information is the number for each CORESET pool index of the 0th value and the 1st value.

2. A step of receiving a zeroth value of a control resource set (COntrol REsource SET (CORESET)) pool index and a first value of a CORESET pool index different from the zeroth value by an upper layer parameter; In a Beam Failure Detection (BFD)-Reference Signal (RS) for PCell, PSCell, and SCell beam failures, when the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value and the set of RS resource indexes for BFD corresponding to the CORESET pool index of the first value are not configured by BFD resource configuration, an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the 0 value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value, and an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the first value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value. determining a set of RS resource indexes for BFD corresponding to the first value of CORESET pool index to provide for an active TCI state for PDCCH reception in the ID; A wireless communication method for a terminal, wherein the number of BFD-RSs limited by terminal capability information is the number for each CORESET pool index of the 0 value and the first value.

3. A transmission unit that transmits a zeroth value of a control resource set (COntrol REsource SET (CORESET)) pool index and a first value of a CORESET pool index different from the zeroth value by an upper layer parameter; In a Beam Failure Detection (BFD)-Reference Signal (RS) for PCell, PSCell, and SCell beam failures, when the terminal determines that the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value and the set of RS resource indexes for BFD corresponding to the CORESET pool index of the first value are not configured by resource configuration for BFD, the terminal determines that the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value is an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the 0 value, and determines that the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value is an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the first value. a control unit for determining a set of RS resource indexes for BFD corresponding to the first value of CORESET pool index to be provided for an active TCI state for PDCCH reception in the ID; A base station, wherein the number of BFD-RSs limited by the terminal capability information is the number for each CORESET pool index of the 0th value and the 1st value.

4. A system including a terminal and a base station, The terminal includes: A receiving unit that receives a zeroth value of a control resource set (COntrol REsource SET (CORESET)) pool index and a first value of a CORESET pool index different from the zeroth value by a higher layer parameter; In a Beam Failure Detection (BFD)-Reference Signal (RS) for PCell, PSCell, and SCell beam failures, when the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value and the set of RS resource indexes for BFD corresponding to the CORESET pool index of the first value are not configured by BFD resource configuration, an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the 0 value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value, and an RS provided for an active transmission configuration indication (TCI) state for downlink control channel (PDCCH) reception in a maximum CORESET ID among the multiple CORESETs corresponding to the CORESET pool index of the first value is the set of RS resource indexes for BFD corresponding to the CORESET pool index of the 0 value. and a control unit for determining a set of RSs provided for an active TCI state for PDCCH reception in the ID as a set of RS resource indexes for BFD corresponding to the first value of CORESET pool index, The number of BFD-RSs limited by the terminal capability information is the number for each CORESET pool index of the 0 value and the first value, The base station, A system comprising a transmitter for transmitting the upper layer parameters.