Terminal, radio communication method, base station, and system

Abstract

To provide a terminal, a method, and a system that appropriately determine a reference signal (RS) for RLM / BFD when settings / an information element for the RLM / BFD is not provided.SOLUTION: A terminal has: a transmission section that transmits capability information indicating support of a transmission configuration indication (TCI) state applicable to a plurality of types of channels being supported by downlink control information (DCI) without downlink (DL) assignment; a receiving section that receives information indicating a plurality of TCI states applicable to a plurality of types of channels and a DCI without DL assignment indicating one or more TCI states of the plurality of TCI states; and a control section that, when a reference signal for beam failure detection (BFD) is not set by a RRC information element, determines the reference signal on the basis of one or more TCI states indicated by the DCI without DL assignment.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In Universal Mobile Telecommunications System (UMTS) networks, Long Term Evolution (LTE) was specified with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). Also, LTE-Advanced (3GPP Rel. 10-14) was 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) are also being considered. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 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 Summary of the Invention [Problem to be solved by the invention]

[0005] In future wireless communication systems, it is being considered that terminals will perform radio link monitoring (RLM) / beam failure detection (BFD).

[0006] However, if the configuration / information element of the reference signal (RS) for RLM / BFD is not provided, it is unclear how to determine the RS for RLM / BFD. If the RS for RLM / BFD is not determined appropriately, the monitoring accuracy / detection accuracy may be degraded.

[0007] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, a base station, and a system that appropriately perform at least one of RLM and BFD. [Means for solving the problem]

[0008] A terminal according to one embodiment of the present disclosure includes a transmitter that transmits capability information indicating support for transmission configuration indication (TCI) states applicable to multiple types of channels being indicated by downlink control information (DCI) without a downlink (DL) assignment, a receiver that receives information indicating multiple TCI states applicable to the multiple types of channels and the DCI without a DL assignment, which indicates one or more TCI states among the multiple TCI states, and a controller that determines a reference signal for beam fault detection (BFD) based on the one or more TCI states indicated by the DCI without a DL assignment when a reference signal for BFD is not set by a Radio Resource Control (RRC) information element. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, at least one of RLM and BFD can be appropriately performed. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating an example of simultaneous beam updating across multiple CCs. [Figure 2] 2A and 2B are diagrams showing an example of a common beam. [Figure 3] FIG. 3 is a diagram showing an example of QCL settings that can be set in Rel. 15 / 16. [Figure 4] FIG. 4 is a diagram showing an example of a QCL setting that cannot be set in Rel. 15 / 16. [Figure 5] FIG. 5 is a diagram illustrating an example of a TCI state indication in the unified TCI state framework in a CA. [Figure 6] FIG. 6 is a diagram illustrating an example of QCL constraints in Case 4. [Figure 7] FIG. 7 is a diagram illustrating an example of QCL constraints in Case 5. [Figure 8] FIG. 8 is a diagram illustrating an example of the number of RLM-RSs. [Figure 9] FIG. 9 illustrates an example of a beam recovery procedure. [Figure 10] FIG. 10 is a diagram illustrating an example of updating the RLM / BFD RS according to the first to third embodiments. [Figure 11] 11A and 11B are diagrams illustrating an example of determining an RLM / BFD RS according to embodiment 2-2-1. [Figure 12] FIG. 12 is a diagram illustrating an example of determining an RLM / BFD RS according to embodiment 2-2-2. [Figure 13] FIG. 13 is a diagram illustrating another example of determining an RLM / BFD RS according to embodiment 2-2-2. [Figure 14] FIG. 14 is a diagram illustrating an example of a MAC CE according to embodiment 3-1. [Figure 15] FIG. 15 is a diagram illustrating an example of a MAC CE according to embodiment 3-2. [Figure 16]FIG. 16 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. [Figure 17] FIG. 17 is a diagram illustrating an example of the configuration of a base station according to an embodiment. [Figure 18] FIG. 18 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. [Figure 19] FIG. 19 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (TCI, spatial relations, QCL) In NR, it is being 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 the UE of at least one of a signal and a channel (referred to as signal / channel) based on the transmission configuration indication state (TCI state).

[0012] The TCI state may represent that which is applied to a downlink signal / channel, and the equivalent of the TCI state which is applied to an uplink signal / channel may be expressed as a spatial relation.

[0013] 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.

[0014] A QCL is an index that indicates the statistical properties of a signal / channel. 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 the Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same between these different signals / channels (i.e., they are QCLs with respect to at least one of these).

[0015] The spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be determined based on a spatial QCL. A QCL (or at least one element of a QCL) in the present disclosure may be replaced with an sQCL (spatial QCL).

[0016] A plurality of types (QCL types) of QCLs may be defined. For example, four QCL types A and B may be provided, each having different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may also be referred to as QCL parameters) are listed below: 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.

[0017] The assumption by a UE 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.

[0018] 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.

[0019] The TCI state may be, for example, information about the QCL between the target channel (in other words, the Reference Signal (RS) for the 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.

[0020] The physical layer signaling may be, for example, Downlink Control Information (DCI).

[0021] The channel for which the TCI state or spatial relationship is set (specified) may be, for example, at least one of a downlink shared channel (Physical Downlink Shared Channel (PDSCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), and an uplink control channel (Physical Uplink Control Channel (PUCCH)).

[0022] Furthermore, the RS that has a QCL relationship with the channel may be, for example, at least one of a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), a CSI-RS for tracking (also called a Tracking Reference Signal (TRS)), and a QCL detection reference signal (also called a QRS).

[0023] An SSB is a signal block that includes 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.

[0024] An RS of QCL type X in a TCI state may refer to an RS that has a relationship of QCL type X with (the DMRS of) a certain channel / signal, and this RS may be called a QCL source of QCL type X in the TCI state.

[0025] A QCL Type A RS is always configured for PDCCH and PDSCH, and a QCL Type D RS may be configured additionally. Because it is difficult to estimate Doppler shift, delay, etc. by one-shot reception of a DMRS, a QCL Type A RS is used to improve channel estimation accuracy. A QCL Type D RS is used to determine the receiving beam when receiving a DMRS.

[0026] For example, TRS1-1, 1-2, 1-3, and 1-4 are transmitted, and TRS1-1 is indicated as a QCL type C / D RS according to the TCI status of the PDSCH. By indicating the TCI status, the UE can use information obtained from past periodic reception / measurement results of TRS1-1 for reception / channel estimation of the DMRS for PDSCH. In this case, the QCL source of the PDSCH is TRS1-1, and the QCL target is the DMRS for PDSCH.

[0027] (Default TCI State / Default Spatial Relationship / Default PL-RS) In RRC connected mode, both when the TCI information in DCI (higher layer parameter TCI-PresentInDCI) is set to "enabled" and when the TCI information in DCI is not set, if the time offset between the reception of a DL DCI (DCI scheduling a PDSCH) and the corresponding PDSCH (PDSCH scheduled by that DCI) is smaller than a threshold (timeDurationForQCL) (applicability condition, first condition), in the case of non-cross-carrier scheduling, the TCI state of the PDSCH (default TCI state) may be the TCI state of the lowest CORESET ID in the latest slot in the active DL BWP of that CC (of the specific UL signal). Otherwise, the TCI state of the PDSCH (default TCI state) may be the TCI state of the lowest TCI state ID of the PDSCH in the active DL BWP of the scheduled CC.

[0028] In Rel.15, separate MAC CEs are required for the activation / deactivation of PUCCH spatial relations and for the activation / deactivation of SRS spatial relations. The PUSCH spatial relations follow the SRS spatial relations.

[0029] In Rel. 16, at least one of the MAC CE for PUCCH spatial-related activation / deactivation and the MAC CE for SRS spatial-related activation / deactivation may not be used.

[0030] If neither the spatial relationship nor the PL-RS for the PUCCH is configured in FR2 (applicable condition, second condition), the default assumptions of the spatial relationship and the PL-RS for the PUCCH (default spatial relationship and default PL-RS) are applied. If neither the spatial relationship nor the PL-RS for the SRS (SRS resource for the SRS or SRS resource corresponding to the SRI in DCI format 0_1 ​​that schedules the PUSCH) is configured in FR2 (applicable condition, second condition), the default assumptions of the spatial relationship and the PL-RS for the PUSCH and SRS scheduled by DCI format 0_1 ​​(default spatial relationship and default PL-RS) are applied.

[0031] If a CORESET is configured in an active DL BWP on the CC (conditions apply), the default spatial relationship and default PL-RS may be the TCI state or QCL assumption of the CORESET with the lowest CORESET ID in the active DL BWP. If a CORESET is not configured in an active DL BWP on the CC, the default spatial relationship and default PL-RS may be the active TCI state with the lowest PDSCH ID in the active DL BWP.

[0032] In Rel.15, the spatial relationship of PUSCH scheduled by DCI format 0_0 follows the spatial relationship of the PUCCH resource with the lowest PUCCH resource ID among the active spatial relationships of PUCCH on the same CC. The network needs to update the PUCCH spatial relationships on all SCells even if no PUCCH is transmitted on the SCell.

[0033] In Rel.16, PUCCH configuration is not required for a PUSCH scheduled by DCI format 0_0. If there is no active PUCCH spatial relationship or no PUCCH resource on the active UL BWP in the CC for a PUSCH scheduled by DCI format 0_0 (applicable condition, second condition), the default spatial relationship and default PL-RS are applied to the PUSCH.

[0034] The application conditions for the default spatial relationship / default PL-RS for SRS may include setting a default beam path loss enable information element for SRS (upper layer parameter enableDefaultBeamPlForSRS) to valid. The application conditions for the default spatial relationship / default PL-RS for PUCCH may include setting a default beam path loss enable information element for PUCCH (upper layer parameter enableDefaultBeamPlForPUCCH) to valid. The application conditions for the default spatial relationship / default PL-RS for PUSCH scheduled by DCI format 0_0 may include setting a default beam path loss enable information element for PUSCH scheduled by DCI format 0_0 (upper layer parameter enableDefaultBeamPlForPUSCH0_0) to valid.

[0035] The above threshold may also be referred to as time duration for QCL, "timeDurationForQCL", "Threshold", "Threshold for offset between a DCI indicating a TCI state and a PDSCH scheduled by the DCI", "Threshold-Sched-Offset", schedule offset threshold, scheduling offset threshold, etc.

[0036] (Multi-TRP) In NR, one or more Transmission / Reception Points (TRPs) (multi-TRPs (MTRPs)) are considered to perform DL transmission to a UE using one or more panels (multi-panels). Also, it is considered that a UE performs UL transmission to one or more TRPs using one or more panels.

[0037] Note that multiple TRPs may correspond to the same cell identifier (ID), or different cell IDs. The cell ID may be a physical cell ID or a virtual cell ID.

[0038] Multi-TRPs (e.g., TRPs #1 and #2) may be connected by ideal / non-ideal backhauls to exchange information, data, etc. Each TRP of the multi-TRP may transmit a different code word (CW) and a different layer. Non-Coherent Joint Transmission (NCJT) may be used as a form of multi-TRP transmission.

[0039] In the NCJT, for example, TRP#1 performs modulation mapping and layer mapping on a first codeword to transmit a first PDSCH using a first number of layers (e.g., two layers) with a first precoding, and TRP#2 performs modulation mapping and layer mapping on a second codeword to transmit a second number of layers (e.g., two layers) with a second precoding.

[0040] Note that multiple PDSCHs (multi-PDSCHs) that are non-coherent may be defined as partially or completely overlapping in at least one of the time and frequency domains, i.e., a first PDSCH from a first TRP and a second PDSCH from a second TRP may overlap in at least one of the time and frequency resources.

[0041] The first PDSCH and the second PDSCH may be assumed to be not quasi-co-located (Quasi-Co-Location (QCL)). Reception of multiple PDSCHs may be interpreted as simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

[0042] Multiple PDSCHs from multiple TRPs (which may also be referred to as multiple PDSCHs) may be scheduled using one DCI (single DCI, single PDCCH) (single-master mode, single-DCI based multi-TRP). Multiple PDSCHs from multiple TRPs may also be scheduled using multiple DCIs (multiple DCI, multiple PDCCHs) (multi-master mode, multi-DCI based multi-TRP).

[0043] In URLLC for multiple TRPs, it is considered that PDSCH (transport block (TB) or codeword (CW)) repetition across multiple TRPs is supported. Repetition schemes (URLLC schemes, e.g., schemes 1, 2a, 2b, 3, and 4) across multiple TRPs in the frequency domain, layer (spatial) domain, or time domain are supported. In scheme 1, multiple PDSCHs from multiple TRPs are space division multiplexed (SDM). In schemes 2a and 2b, PDSCHs from multiple TRPs are frequency division multiplexed (FDM). In scheme 2a, the redundancy version (RV) is the same for multiple TRPs. In scheme 2b, the RVs may be the same or different for multiple TRPs. In schemes 3 and 4, multiple PDSCHs from multiple TRPs are time division multiplexed (TDM). In scheme 3, multiple PDSCHs from multiple TRPs are transmitted in one slot. In scheme 4, multiple PDSCHs from multiple TRPs are transmitted in different slots.

[0044] Such a multi-TRP scenario allows for more flexible transmission control using good quality channels.

[0045] To support intra-cell (having the same cell ID) and inter-cell (having different cell IDs) multi-TRP transmission based on multiple PDCCHs, in the RRC configuration information for linking multiple pairs of PDCCHs and PDSCHs with multiple TRPs, one control resource set (CORESET) in the PDCCH configuration information (PDCCH-Config) may correspond to one TRP.

[0046] If at least one of the following conditions 1 and 2 is satisfied, the UE may determine that the transmission is a multi-TRP transmission based on the multi-DCI transmission. In this case, the TRP may be replaced with a CORESET pool index. [Condition 1] A CORESET pool index of 1 is set. [Condition 2] Two different values ​​of the CORESET pool index (for example, 0 and 1) are set.

[0047] If the following condition is met, the UE may determine that the state is multi-TRP based on a single DCI, in which case the two TRPs may be interpreted as two TCI states indicated by the MAC CE / DCI. [conditions] "Enhanced TCI States Activation / Deactivation for UE-specific PDSCH MAC CE" is used to indicate one or two TCI states for one codepoint of the TCI field in the DCI.

[0048] The DCI for common beam instruction may be a UE-specific DCI format (e.g., DL DCI format (e.g., 1_1, 1_2), UL DCI format (e.g., 0_1, 0_2)), or may be a UE-group common DCI format.

[0049] (Simultaneous beam update of multiple CCs) In Rel.16, one MAC CE can update the beam index (TCI state) of multiple CCs.

[0050] The UE can be configured by RRC with up to two applicable CC lists (e.g., applicable-CC-list). When two applicable CC lists are configured, the two applicable CC lists may correspond to in-band CA in FR1 and in-band CA in FR2, respectively.

[0051] Activation of TCI states on PDCCH The MAC CE activates the TCI states associated with the same CORESET ID on all BWP / CCs in the applicable CC list.

[0052] Activation of TCI states for PDSCH The MAC CE activates the TCI states on all BWP / CCs in the applicable CC list.

[0053] A-SRS / SP-SRS Spatial Relationship Activation The MAC CE activates spatial relationships associated with the same SRS resource ID on all BWPs / CCs in the applicable CC list.

[0054] In the example of Figure 1, the UE is configured with an applicable CC list indicating CCs #0, #1, #2, and #3, and a list indicating 64 TCI states for the CORESET or PDSCH of each CC. When one TCI state of CC #0 is activated by the MAC CE, the corresponding TCI states are activated in CCs #1, #2, and #3.

[0055] Such simultaneous beam updating is considered applicable only to the single TRP case.

[0056] For PDSCH, the UE may follow procedure A. [Step A] The UE receives activation commands to map up to eight TCI states to codepoints in the DCI field (TCI field) within one CC / DL BWP or within one set of CC / BWPs. If one set of TCI state IDs is activated for one set of CC / DL BWPs, then the applicable list of CCs is determined by the CC indicated in the activation command, and the same set of TCI states applies to all DL BWPs within the indicated CC. A set of TCI state IDs can be activated for one set of CC / DL BWPs only if the UE is not provided with multiple different values ​​of the CORESETPoolIndex in the CORESET information element (ControlResourceSet) and at least one TCI codepoint that maps to two TCI states.

[0057] For PDCCH, the UE may follow procedure B. [Step B] If the UE is provided with up to two lists of cells for simultaneous TCI state activation by the simultaneous TCI cell list (simultaneousTCI-CellList) via the simultaneous TCI update list (at least one of simultaneousTCI-UpdateList-r16 and simultaneousTCI-UpdateListSecond-r16), the UE applies antenna port quasi co-location (QCL) provided by TCI states with the same activated TCI state ID value to the CORESET with index p in all configured DL BWPs of all configured cells in one list determined from the serving cell index provided by the MAC CE command. A simultaneous TCI cell list can be provided for simultaneous TCI state activation only if the UE is not provided with different values ​​of the CORESET pool index (CORESETPoolIndex) in the CORESET information element (ControlResourceSet) and at least one TCI codepoint that maps to two TCI states.

[0058] For semi-persistent (SP) / aperiodic (AP)-SRS, the UE may follow procedure C. [Step C] For one set of CCs / BWPs, when the spatial relationship information (spatialRelationInfo) for the SP or AP-SRS resources configured by the SRS resource information element (higher layer parameter SRS-Resource) is activated / updated by the MAC CE, then the applicable list of the CC is indicated by the simultaneous spatial update list (higher layer parameter simultaneousSpatial-UpdateList-r16 or simultaneousSpatial-UpdateListSecond-r16), and the spatial relationship information is applied to the SP or AP-SRS resources with the same SRS resource ID in all BWPs within the indicated CC. The spatial relation information (spatialRelationInfo) for the SP or AP-SRS resources configured by the SRS resource information element (higher layer parameter SRS-Resource) for one set of CC / BWP is activated / updated by the MAC CE only if the UE is not provided with multiple different values ​​of the CORESET pool index (CORESETPoolIndex) in the CORESET information element (ControlResourceSet) and is not provided with at least one TCI codepoint that maps to two TCI states.

[0059] The simultaneous TCI cell list (simultaneousTCI-CellList) and the simultaneous TCI update list (at least one of simultaneousTCI-UpdateList1-r16 and simultaneousTCI-UpdateList2-r16) are lists of serving cells whose TCI relationships can be updated simultaneously using the MAC CE. simultaneousTCI-UpdateList1-r16 and simultaneousTCI-UpdateList2-r16 do not include the same serving cell.

[0060] The simultaneous spatial update list (at least one of the upper layer parameters simultaneousSpatial-UpdatedList1-r16 and simultaneousSpatial-UpdatedList2-r16) is a list of serving cells whose spatial relationships can be updated simultaneously using the MAC CE. simultaneousSpatial-UpdatedList1-r16 and simultaneousSpatial-UpdatedList2-r16 do not contain the same serving cell.

[0061] Here, the simultaneous TCI update list and the simultaneous spatial update list are configured by the RRC, the CORESET pool index of the CORESET is configured by the RRC, and the TCI codepoint mapped to the TCI state is indicated by the MAC CE.

[0062] (Unified / Common TCI Framework) The unified TCI framework allows UL and DL channels to be controlled by a common framework. Instead of specifying TCI states or spatial relationships for each channel as in Rel. 15, the unified TCI framework may specify a common beam (common TCI state) and apply it to all UL and DL channels, or may apply a common beam for UL to all UL channels and a common beam for DL ​​to all DL channels.

[0063] One common beam for both DL and UL, or one common beam for DL ​​and one common beam for UL (two common beams overall) are considered.

[0064] The UE may assume the same TCI state for UL and DL (joint TCI state, joint TCI pool, joint common TCI pool, joint TCI state set). The UE may assume different TCI states for UL and DL (separate TCI state, separate TCI pool, UL separate TCI pool and DL separate TCI pool, separate common TCI pool, UL common TCI pool and DL common TCI pool).

[0065] The default beams for UL and DL may be aligned via MAC CE based beam management (MAC CE level beam direction). The default TCI state of the PDSCH may be updated to align with the default UL beam (spatial relationship).

[0066] DCI-based beam management (DCI-level beam indication) may indicate a common beam / unified TCI state from the same TCI pool (joint common TCI pool, joint TCI pool, set) for both UL and DL. X (>1) TCI states may be activated by the MAC CE. The UL / DL DCI may select one from the X active TCI states. The selected TCI state may apply to both UL and DL channels / RS.

[0067] The TCI pool (set) may be multiple TCI states configured by RRC parameters, or multiple TCI states (active TCI states, active TCI pools, sets) activated by the MAC CE among the multiple TCI states configured by RRC parameters. Each TCI state may be a QCL type A / D RS. SSB, CSI-RS, or SRS may be configured as the QCL type A / D RS.

[0068] The number of TCI states corresponding to each of one or more TRPs may be specified. For example, the number N (≧1) of TCI states applied to UL channels / RSs (UL TCI states) and the number M (≧1) of TCI states applied to DL channels / RSs (DL TCI states) may be specified. At least one of N and M may be notified / configured / instructed to the UE via higher layer signaling / physical layer signaling.

[0069] In the present disclosure, when N=M=X (X is any integer), it may mean that X TCI states (joint TCI states) common to UL and DL (corresponding to X TRPs) are notified / configured / instructed to the UE. Also, when N=X (X is any integer) and M=Y (Y may be any integer, Y=X), it may mean that X UL TCI states (corresponding to X TRPs) and Y DL TCI states (i.e., separate TCI states) (corresponding to Y TRPs) are notified / configured / instructed to the UE.

[0070] For example, when N=M=1 is written, this may mean that a TCI state common to one UL and DL for a single TRP is notified / configured / indicated to the UE (joint TCI state for a single TRP).

[0071] Also, for example, when N=1 and M=1, it may mean that one UL TCI state and one DL TCI state for a single TRP are separately notified / configured / instructed to the UE (separate TCI states for a single TRP).

[0072] Also, for example, when N=M=2 is written, this may mean that a TCI state common to multiple (two) ULs and DLs for multiple (two) TRPs is notified / configured / instructed to the UE (joint TCI state for multiple TRPs).

[0073] Also, for example, when N=2 and M=2, this may mean that the UE is notified / configured / instructed to have multiple (two) UL TCI states and multiple (two) DL TCI states for multiple (two) TRPs (separate TCI states for multiple TRPs).

[0074] In the above example, the case where the values ​​of N and M are 1 or 2 has been described, but the values ​​of N and M may be 3 or more, and N and M may be different.

[0075] In the example of Figure 2A, RRC parameters (information elements) configure multiple TCI states for both DL and UL. The MAC CE may activate multiple TCI states from the configured multiple TCI states. The DCI may indicate one of the activated multiple TCI states. The DCI may be a UL / DL DCI. The indicated TCI state may apply to at least one (or all) of the UL / DL channels / RS. One DCI may indicate both UL TCI and DL TCI.

[0076] In the example of FIG. 2A, a point may be one TCI state that applies to both the UL and DL, or two TCI states that apply to the UL and DL, respectively.

[0077] At least one of the multiple TCI states configured by the RRC parameters and the multiple TCI states activated by the MAC CE may be referred to as a TCI pool (common TCI pool, joint TCI pool, TCI state pool). The multiple TCI states activated by the MAC CE may be referred to as an active TCI pool (active common TCI pool).

[0078] In the present disclosure, higher layer parameters (RRC parameters) for setting multiple TCI states may be referred to as configuration information for setting multiple TCI states, or simply as "configuration information." Also, in the present disclosure, being instructed to set one of multiple TCI states using DCI may mean receiving indication information instructing one of the multiple TCI states included in DCI, or simply receiving "instruction information."

[0079] In the example of Figure 2B, the RRC parameters configure multiple TCI states (joint common TCI pools) for both DL and UL. The MAC CE may activate multiple TCI states (active TCI pools) from the configured multiple TCI states. Separate active TCI pools for UL and DL may be configured / activated.

[0080] The DL DCI or a new DCI format may select (indicate) one or more (e.g., one) TCI states. The selected TCI state may be applied to one or more (or all) DL channels / RSs. The DL channels may be PDCCH / PDSCH / CSI-RS. The UE may determine the TCI state of each DL channel / RS using the TCI state behavior (TCI framework) of Rel. 16. The UL DCI or a new DCI format may select (indicate) one or more (e.g., one) TCI states. The selected TCI state may be applied to one or more (or all) UL channels / RSs. The UL channels may be PUSCH / SRS / PUCCH. In this way, different DCIs may indicate the UL TCI and the DL DCI separately.

[0081] The existing DCI format 1_2 / 1_2 may be used to indicate the common TCI status.

[0082] The common TCI framework may have separate TCI states for DL ​​and UL.

[0083] The common TCI framework may have separate TCI states for DL ​​and UL. It is not preferred to use DCI format 1_1 / 1_2 to indicate common TCI states for UL only.

[0084] (Unified TCI Framework for Carrier Aggregation (CA)) The introduction of a unified TCI state framework for CA is being considered for NR Rel. 17 and later. The common TCI state indicated to the UE is expected to be common across CCs (cells) (at least between CCs, QCL type D). This is because the existing specifications (Rel. 15 / 16) do not support simultaneous reception of different DL channels / RSs in QCL type D, or simultaneous transmission of UL channels / RSs with different spatial relationships, except for cases such as transmission and reception using multiple TRPs.

[0085] However, when instructing beams using individual MAC CE / DCI for each CC, there is a concern that signaling overhead will increase.

[0086] In addition, in the unified TCI framework, common TCI state ID update / activation is being considered to provide common QCL information / common UL transmit spatial filter across a set of configured CCs.

[0087] The following options 1 and 2 are being considered for the TCI state pool for CA.

[0088] [Option 1] A single TCI state pool configured by RRC for a set of configured multiple CCs (cells) / BWPs may be shared (configured). For example, a cell group TCI state may be defined, or the TCI state pool for PDSCH in the reference cell may be reused. In the TCI state, there may be no CC (cell) ID for the QCL type-A RS, and the CC (cell) ID for the QCL type-A RS may be determined according to the target CC (cell) of the TCI state.

[0089] In option 1, a common TCI state pool is configured for each of multiple CC / BWPs, so that when one common TCI state is indicated in the MAC CE / DCI, the indicated common TCI state may be applied to all CC / BWPs (all CC / BWPs included in the pre-configured CC / BWP list).

[0090] [Option 2] For each individual CC, a TCI state pool may be configured by the RRC.

[0091] In Option 2, as in Rel. 16, the applicable CC / BWP list for simultaneous beam updates is pre-configured by RRC, and if a beam update is performed in MAC CE / DCI for any CC / BWP included in the CC / BWP list, the update may be applied to all CC / BWPs.

[0092] In option 1, a common TCI state pool is configured (shared) by RRC for multiple CCs, the TCI states in the common TCI state pool are indicated by a common TCI state ID, and one RS determined based on that TCI state is used to indicate QCL type D RSs across the set of configured CCs (Constraint 1).

[0093] In option 2, a separate common TCI state pool is configured by RRC for each CC, the TCI states in the common state pool are indicated by a common TCI state ID, and one RS determined based on that TCI state is used to indicate QCL type D RSs across the set of configured CCs (Constraint 2).

[0094] (QCL setting constraints) As mentioned above, it is being considered to control beams of multiple types of channels using a common TCI framework with a common beam instruction / activation (MAC CE / DCI), but this control is performed for one BWP / CC (cell).

[0095] Simultaneous beam updating across multiple CCs, specified in Rel. 16, allows beams of multiple BWPs / CCs to be updated with a single MAC CE beam instruction, thereby reducing beam control overhead.

[0096] In Rel.15 / 16, the QCL source RS (Type A RS and Type D RS) configured in the TCI state of DMRS for PDCCH / DMRS for PDSCH is limited to the following cases (Case 1) to (Case 3): (Case 1) Type A RS is a tracking reference signal (TRS) (CSI-RS for which the higher layer parameter trs-Info is set), and Type D RS is a CSI-RS equal to Type A RS. (Case 2) Type A RS is a TRS, and Type D RS is a CSI-RS for which the higher layer parameter "repetition" is set. (Case 3) The type A RS is a CSI-RS in which the higher layer parameter trs-Info is not set and the higher layer parameter repetition is not set, and the type D RS is a CSI-RS equivalent to the type A RS.

[0097] Therefore, the only case where Type A RS and Type D RS are different CSI-RS resources is the above case (Case 2).

[0098] Furthermore, the CSI-RS for which the higher layer parameter "repetition" is set may be configured to assist the UE in determining a receiving beam. However, the UE can determine a receiving beam without using the CSI-RS for which the higher layer parameter "repetition" is set.

[0099] On the other hand, since the network (NW, for example, a base station) transmits a TRS as a Type A RS, it is generally considered that the operation in the above case (Case 1) in which the TRS is used as a Type D RS is the norm.

[0100] It is preferable to enable simultaneous beam updating across multiple CCs even in a common TCI framework. However, the QCL setting between the DMRS for PDCCH / DMRS for PDSCH and the TRS in multiple CCs has the following constraints. Note that in the present disclosure, the QCL setting constraint may be referred to as a QCL setting constraint, a QCL constraint, a QCL chain, or the like.

[0101] For example, in Rel.15 / 16, the configuration shown in Fig. 3 is possible. Assume that CC#0, which is a special cell (SpCell) (primary cell (PCell) or primary secondary cell (PSCell)), and #1, #2, and #3, which are SCells, are configured, and SSB, TRS, and DMRS for PDCCH / DMRS for PDSCH (which may simply be referred to as DMRS) are transmitted in each CC. In this case, the TRS of each CC has QCL type C and D relationships with the SSB of CC#0, and the PDCCH of each CC has QCL type A and D relationships with the TRS of the same CC.

[0102] For example, in Rel.15 / 16, the configuration shown in Figure 4 is not possible. As in Figure 3 above, if the TRS of each CC is in a QCL type C or D relationship with the SSB of CC#0 and the DMRS of each CC is in a QCL type A relationship with the TRS of the same CC, the DMRS of CC#1, 2, and 3 cannot be in a QCL type D relationship with the TRS of CC#0 (shown by the dashed line). If the TCI state of the DMRS for PDCCH / DMRS for PDSCH is TRS, the RS for QCL type A and the RS for QCL type D must have the same TRS.

[0103] When a TRS is set as a QCL type A / D RS in the TCI state of a CC, the TRS of another CC cannot be set as the QCL type A / D RS. Therefore, even when a common TCI pool or a common TCI is set / updated / instructed between multiple CCs, the TCI state (TCI state including the QCL type A / D RS) is set for each CC.

[0104] When a CSI-RS is configured as a QCL type D RS in the TCI state of a CC, a CSI-RS of another CC may be configured as a QCL type D RS in the TCI state of a PDCCH / PDSCH of the CC. Even in this case, a CSI-RS / TRS of the same CC must be configured as a QCL type A RS in the TCI state. This is because the QCL type A RS indicates that parameters that determine channel characteristics, such as delay spread and average delay, are the same, and therefore the values ​​of these parameters may differ in different CCs.

[0105] The cell for the QCL type A RS must be the same as the cell for the DMRS for PDSCH / PDCCH with the TCI state configured.

[0106] As mentioned above, if a QCL Type D RS is a TRS, the QCL Type D RS must be the same as a QCL Type A RS. Combined with the above, if a QCL Type D RS is a TRS, the cell of the QCL Type D RS must be the same as the cell of a PDSCH / PDCCH DMRS with the TCI state configured.

[0107] If a QCL type D RS is a CSI-RS with repetition configured (having CSI-RS resources in an NZP CSI-RS resource set with the upper layer parameter repetition configured (the upper layer parameter repetition is ON)), the cell for that QCL type D RS may be different from the cell for the DMRS for PDSCH / PDCCH with the TCI state configured.

[0108] In Rel. 17 and later, in the common TCI state framework in CA, consideration is being given to introducing QCL constraints different from the QCL constraints specified up to Rel. 16 described above into constraints on QCL settings of a common TCI state across a set of multiple CCs (multiple CCs associated with beams from the same base station). In this disclosure, the QCL constraints specified up to Rel. 16 may be referred to as first QCL constraints. Furthermore, QCL constraints different from the QCL constraints specified up to Rel. 16 may be referred to as second QCL constraints.

[0109] For a QCL source RS in a common TCI state, the UE may be configured with upper layer parameters (e.g., qcl_Type1) for the RS of the first QCL type (e.g., QCL type A) as well as upper layer parameters (e.g., qcl_Type2) for the second QCL type (e.g., QCL type D).

[0110] In a common TCI state, the RSs of the first QCL type and the second QCL type may be different, for example, the UE may assume that the QCL type A RSs and the QCL type D RSs are configured differently.

[0111] In a common TCI state, when the RS of the first QCL type and the RS of the second QCL type are different, the case where the RS of the first QCL type becomes the TRS and the RS of the second QCL type becomes the CSI-RS with repetition set (having the upper layer parameter repetition) may be excluded.

[0112] The RS of the first QCL type and the RS of the second QCL type may be RSs in different CCs included in a common CC list. Note that the RS of the first QCL type and the RS of the second QCL type may be RSs with the same RS ID or the same TCI ID in different CCs included in a common CC list. Also, the RS of the first QCL type and the RS of the second QCL type may be RSs included in a common RS list / common TCI status list. These allow the NW to appropriately configure / instruct a QCL type D RS with little control overhead without transmitting additional CSI-RS resources (e.g., CSI-RSs for which repetition is configured).

[0113] The following describes a second QCL constraint that can be configured for a UE, which is being considered for introduction in Rel. 17 and later. The UE may assume that the QCL source RSs (QCL Type A RSs and QCL Type D RSs) configured in the TCI state of DMRS for PDCCH / DMRS for PDSCH comply with the following (Case 4) and (Case 5) in addition to / instead of the above-mentioned cases (Case 1) to (Case 3): (Case 4) The RS of the first QCL type is a TRS (CSI-RS with the upper layer parameter trs-Info set), and the RS of the second QCL type is a TRS (CSI-RS with the upper layer parameter trs-Info set). (Case 5) The RS of the first QCL type is a TRS (CSI-RS in which the higher layer parameter trs-Info is set), and the RS of the second QCL type is an SSB.

[0114] In addition, the source RS of the second QCL type in the TCI state of the DMRS for PDCCH / DMRS for PDSCH in each CC may be required to be the same RS between CCs.

[0115] (Case 4) In case 4, the RS of the first QCL type and the RS of the second QCL type may be different CSI-RS resources.

[0116] Fig. 6 is a diagram showing an example of QCL constraints in Case 4. In the example shown in Fig. 6, the TRS of each CC has a QCL type C or D relationship with the SSB of CC#0. The DMRS of each CC (DMRS for PDCCH / DMRS for PDSCH) has a QCL type A relationship with the TRS of the same CC. In this case, the DMRS of each CC may have a QCL type D relationship with the TRS of CC#0.

[0117] (Case 5) For the first QCL type RS, TRS is configured for time-frequency tracking because it allows for higher resource density and more accurate time-frequency correction compared to SSB, while the second QCL type RS is used to obtain UL / DL (transmit / receive) spatial domain filters and can operate at SSB resource density.

[0118] Fig. 7 is a diagram showing an example of QCL constraints in Case 5. In the example shown in Fig. 7, the TRS of each CC has a QCL type C or D relationship with the SSB of CC#0. The DMRS of each CC (DMRS for PDCCH / DMRS for PDSCH) has a QCL type A relationship with the TRS of the same CC. In this case, the DMRS of each CC may have a QCL type D relationship with the SSB of CC#0.

[0119] In Rel. 17 and later, in the common TCI state framework in CA, it is considered that the constraints on the QCL configuration of the common TCI state across a set of multiple CCs (multiple CCs associated with beams from the same base station) are at least one of the following options 1 and 2 (2-1 to 2-3): [Option 1]: From one or more common TCI states, a separate QCL Type D RS for each CC among the multiple CCs is determined, and the determined QCL Type D RS for each CC is associated with the same QCL Type D RS (i.e., Cases 1 to 3 above). [Option 2]: From one or more common TCI states, a single QCL Type D RS for each CC among the multiple CCs is determined, subject to at least one QCL constraint from Option 2-1 to Option 2-3 below; [[Option 2-1]]: Case 4 above. [[Option 2-2]]: Case 5 above. [[Options 2-3]]: Cases 4 and 5 above.

[0120] (Radio Link Monitoring (RLM)) In NR, Radio Link Monitoring (RLM) is used.

[0121] In NR, a base station may configure a Radio Link Monitoring Reference Signal (Radio Link Monitoring RS (RLM-RS)) for a UE for each BWP using higher layer signaling. The UE may receive configuration information for RLM (e.g., the "RadioLinkMonitoringConfig" information element of RRC).

[0122] The configuration information for the RLM may include fault detection resource configuration information (e.g., the upper layer parameter "failureDetectionResourcesToAddModList") and parameters related to the RLM-RS (e.g., the upper layer parameter "RadioLinkMonitoringRS").

[0123] The parameters related to the RLM-RS may include information indicating that it corresponds to the purpose of RLM, an index corresponding to the resource of the RLM-RS (e.g., an index included in the upper layer parameter "failureDetectionResources" (RadioLinkMonitoringRS in failureDetectionResourcesToAddModList)), etc. The index may be, for example, an index of the CSI-RS resource configuration (e.g., a non-zero power CSI-RS resource ID) or an SS / PBCH block index (SSB index). The purpose information may indicate a beam failure, a (cell-level) Radio Link Failure (RLF), or both.

[0124] The UE may identify the RLM-RS resource based on the index corresponding to the resource of the RLM-RS, and perform RLM using the RLM-RS resource.

[0125] In the Rel.16 RLM procedure, the UE follows the implicit RLM-RS determination procedure:

[0126] [Implicit RLM-RS determination procedure] If the UE is not provided with a Radio Link Monitoring RS (RLM-RS) and the UE is provided with a TCI state including one or more CSI-RS for PDCCH reception, the UE shall follow steps 1 to 4 below.

[0127] Step 1 If the active TCI state for PDCCH reception includes only one RS, the UE uses the RS provided for the active TCI state for PDCCH reception for RLM. Step 2 If the active TCI state for PDCCH reception includes two RSs, the UE assumes that one RS has QCL type D, and the UE uses that RS with QCL type D for RLM. The UE does not assume that both RSs have QCL type D. Step 3 The UE is not required to use aperiodic or semi-persistent RS for RLM. Step 4 L max For =4, the UE selects N provided for the active TCI state for PDCCH reception in the multiple CORESETs associated with the multiple search space sets in order of the smallest monitoring periodicity. RLM If more than one CORESET is associated with multiple search space sets with the same monitoring period, the UE determines the order of the CORESETs from the highest CORESET index.

[0128] where L max is the maximum number of SS / PBCH block indexes in a cell. The maximum number of SS / PBCH blocks transmitted in a half-frame is L max is.

[0129] In this way, if the UE is not provided with an RLM-RS, the UE makes an implicit RLM-RS decision and uses the active TCI state for PDCCH reception for RLM. max If = 4, the UE first sorts the search space sets in ascending order of monitoring period, then in descending order of CORESET index, N RLM Select RS. Select CORESET.

[0130] The UE must be connected to the N LR-RLM Up to N RLM-RSs can be configured. LR-RLM From RLM-RS, L max Depends on N RLMUp to RLM-RSs are used for RLM. In Rel. 16, as shown in Figure 8, max N if =4 RLM = 2, and L max N when =8 RLM = 4, and L max = 64, N RLM =8.

[0131] (Beam Failure Detection(BFD) / Beam Failure Recovery(BFR)) In NR, communication is performed using beamforming. For example, a UE and a base station (e.g., a gNB (gNodeB)) may use a beam used to transmit a signal (also called a transmit beam or Tx beam) and a beam used to receive a signal (also called a receive beam or Rx beam).

[0132] When beamforming is used, it is expected that radio link quality will deteriorate due to increased susceptibility to interference from obstacles. This deterioration in radio link quality may lead to frequent radio link failures (RLF). Since RLF requires cell reconnection, frequent RLF occurrences will result in a degradation of system throughput.

[0133] In NR, in order to suppress the occurrence of RLF, when the quality of a specific beam deteriorates, a procedure for switching to another beam (which may also be called Beam Recovery (BR), Beam Failure Recovery (BFR), or L1 / L2 (Layer 1 / Layer 2) beam recovery) is performed. The BFR procedure may also be simply called BFR.

[0134] Note that a beam failure (BF) in this disclosure may also be referred to as a link failure.

[0135] 9 is a diagram showing an example of a beam recovery procedure in Rel.15 NR. The number of beams is merely an example and is not limited to this. In the initial state (step S101), the UE performs measurements based on Reference Signal (RS) resources transmitted using two beams.

[0136] The RS may be at least one of a Synchronization Signal Block (SSB) and a Channel State Information RS (CSI-RS). The SSB may also be called an SS / PBCH (Physical Broadcast Channel) block.

[0137] The RS may be at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), a Mobility Reference Signal (MRS), a signal included in an SSB, an SSB, a CSI-RS, a Demodulation Reference Signal (DMRS), a beam-specific signal, etc., or a signal configured by extending or modifying any of these. The RS measured in step S101 may also be called an RS for beam failure detection (Beam Failure Detection RS (BFD-RS)), an RS for use in a beam recovery procedure (BFR-RS), etc.

[0138] In step S102, the UE cannot detect the BFD-RS (or the reception quality of the RS is degraded) due to radio wave jamming from the base station. Such jamming can be caused by, for example, obstacles, fading, interference, etc. between the UE and the base station.

[0139] The UE detects a beam failure when a predetermined condition is met. The UE may detect the occurrence of a beam failure, for example, when the Block Error Rate (BLER) is less than a threshold for all configured BFD-RS (BFD-RS resource configurations). When the occurrence of a beam failure is detected, the lower layer (physical (PHY) layer) of the UE may notify (indicate) a beam failure instance to the upper layer (MAC layer).

[0140] The criteria for the determination are not limited to BLER, but may be Layer 1 Reference Signal Received Power (L1-RSRP) in the physical layer. Also, instead of or in addition to RS measurement, beam failure detection may be performed based on a downlink control channel (PDCCH). The BFD-RS may be expected to be quasi-co-located (QCL) with the DMRS of the PDCCH monitored by the UE.

[0141] Here, QCL is an index that indicates the statistical properties of a channel. For example, if a signal / channel and another signal / channel have a QCL relationship, it may mean that it can be assumed that at least one of the Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same between these different signals / channels (i.e., they are QCLs with respect to at least one of these).

[0142] The spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be determined based on a spatial QCL. A QCL (or at least one element of a QCL) in the present disclosure may be replaced with an sQCL (spatial QCL).

[0143] Information about BFD-RS (e.g., RS index, resource, number, number of ports, precoding, etc.), information about beam fault 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 also be referred to as information about BFR resources, etc.

[0144] When a higher layer (e.g., MAC layer) of the UE receives a beam failure instance notification from the PHY layer of the UE, it may start a predetermined timer (which may be called a beam failure detection timer). If the MAC layer of the UE receives a certain number of beam failure instance notifications (e.g., beamFailureInstanceMaxCount configured by RRC) before the timer expires, it may trigger a BFR (e.g., start one of the random access procedures described below).

[0145] If there is no notification from the UE, or if the base station receives a predetermined signal (beam recovery request in step S104) from the UE, the base station may determine that the UE has detected a beam failure.

[0146] 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 a new candidate RS, a new candidate beam identification RS (NCBI-RS), a CBI-RS, a CB-RS (Candidate Beam RS), or the like. The NCBI-RS may be the same as or different from the BFD-RS. The new candidate beam may also be simply called a candidate beam or candidate RS.

[0147] 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 whose L1-RSRP exceeds a threshold among the configured NCBI-RSs. Note that the criteria for determination are not limited to L1-RSRP. The L1-RSRP for SSB may be called SS-RSRP. The L1-RSRP for CSI-RS may be called CSI-RSRP.

[0148] 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. Information about the new candidate RS (or NCBI-RS) may be acquired based on information about the BFD-RS. Information about the NCBI-RS may be referred to as information about NBCI resources, etc.

[0149] Note that BFD-RS, NCBI-RS, etc. may be read as Radio Link Monitoring RS (RLM-RS).

[0150] In step S104, the UE that has identified the new candidate beam transmits a beam failure recovery request (BFRQ). The beam recovery request may also be called a beam recovery request signal, a beam failure recovery request signal, or the like.

[0151] The BFRQ may be transmitted using, for example, at least one of an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), and a configured grant (CG) PUSCH.

[0152] The BFRQ may include information of the new candidate beam / new candidate RS identified in step S103. Resources 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, an RS index, a resource index (e.g., a CSI-RS resource indicator (CRI) or an SSB resource indicator (SSBRI)), etc.

[0153] In Rel. 15 NR, contention-based BFR (CB-BFR), which is a BFR based on a contention-based random access (RA) procedure, and contention-free BFR (CF-BFR), which is a BFR based on a contention-free random access procedure, are under consideration. In CB-BFR and CF-BFR, a UE may transmit a preamble (also referred to as an RA preamble, a random access channel (Physical Random Access Channel (PRACH)), a RACH preamble, etc.) as a BFRQ using a PRACH resource.

[0154] In CB-BFR, a UE may transmit a preamble randomly selected from one or more preambles. In CF-BFR, a UE may transmit a preamble assigned specifically to the UE by the base station. In CB-BFR, a base station may assign the same preamble to multiple UEs. In CF-BFR, a base station may assign a preamble individually to each UE.

[0155] Note that CB-BFR and CF-BFR may be referred to as CB PRACH-based BFR (CBRA-BFR) and CF PRACH-based BFR (CFRA-BFR), respectively. CBRA-BFR may be referred to as CBRA for BFR. CFRA-BFR may be referred to as CFRA for BFR.

[0156] Regardless of whether CB-BFR or CF-BFR is used, information about the PRACH resource (RA preamble) may be notified by, for example, higher layer signaling (such as RRC signaling). For example, the information may include information indicating a correspondence relationship between the detected DL-RS (beam) and the PRACH resource, and a different PRACH resource may be associated with each DL-RS.

[0157] In step S105, the base station that has 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.

[0158] 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 PDCCH (DCI) scrambled with a cyclic redundancy check (CRC) by a UE identifier (e.g., a Cell-Radio RNTI (C-RNTI)). The UE may determine at least one of a transmit beam and a receive beam to use based on the beam reconfiguration information.

[0159] The UE may monitor the response signal based on at least one of a control resource set (CORESET) for BFR and a search space set for BFR.

[0160] For CB-BFR, contention resolution may be determined to be successful if the UE receives a PDCCH corresponding to the C-RNTI associated with the UE.

[0161] Regarding the process of step S105, a period for the UE to monitor a response to the BFRQ from a base station (e.g., a gNB) 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.

[0162] 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.

[0163] 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.

[0164] Rel.15 supports the use of a random access procedure to perform beam recovery procedures (e.g., BFRQ notification) for beam failures detected in an SpCell (PCell / PSCell). On the other hand, Rel.16 supports the use of at least one of PUCCH (e.g., Scheduling Request (SR)) transmission for BFR and MAC CE (e.g., UL-SCH) transmission for BFR to perform beam recovery procedures (e.g., BFRQ notification) for beam failures detected in an SCell.

[0165] For example, the UE may transmit information about beam failure using MAC CE-based two-step. The information about beam failure may include information about the cell that detected the beam failure and information about new candidate beams (or new candidate RS indices).

[0166] [Step 1] If a BF is detected, a PUCCH-BFR (scheduling request (SR)) may be transmitted from the UE to the PCell / PSCell. Then, an UL grant (DCI) for step 2 below may be transmitted from the PCell / PSCell to the UE. If a beam failure is detected and there is a MAC CE (or UL-SCH) for transmitting information about a new candidate beam, step 1 (e.g., PUCCH transmission) may be omitted and step 2 (e.g., MAC CE transmission) may be performed.

[0167] [Step 2] Then, the UE may transmit information about the cell where beam failure was detected (failed) (e.g., cell index) and information about the new candidate beam to the base station (PCell / PSCell) via an uplink channel (e.g., PUSCH) using MAC CE. After that, through the BFR procedure, the QCL of the PDCCH / PUCCH / PDSCH / PUSCH may be updated to the new beam after a predetermined period (e.g., 28 symbols) after receiving a response signal from the base station.

[0168] Note that the numbers of these steps are for explanatory 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.

[0169] (BFD-RS) In Rel. 16, for each BWP of one serving cell, the UE may be provided with a set of periodic (P)-CSI-RS resource configuration indices q0 via failure detection resources (failureDetectionResources, failureDetectionResourcesToAddModList, RadioLinkMonitoringConfig) and at least one set of P-CSI-RS resource configuration indices and SS / PBCH block indices q1 via the candidate beam RS list (candidateBeamRSList) or the extended candidate beam RS list (candidateBeamRSListExt-r16) or the candidate beam RS list for SCell (candidateBeamRSSCellList-r16).

[0170] Here, q0 bar is written as "q0" with an overline. Hereinafter, q0 bar will be written simply as q0. q1 bar is written as "q1" with an overline. Hereinafter, q1 bar will be written simply as q1.

[0171] The set of P-CSI-RS resources q0 provided by the failure detection resources may be referred to as explicit BFD-RS.

[0172] The UE may perform L1-RSRP measurements, etc., using RS resources corresponding to indices included in at least one of set q0 and set q1 to detect beam failure.

[0173] In the present disclosure, providing the above-mentioned higher layer parameters indicating information on indexes corresponding to BFD resources may be interchangeably read as configuring BFD resources, configuring a BFD-RS, etc. In the present disclosure, BFD resources, periodic CSI-RS resource configuration index or SSB index set q0, BFD-RS, BFD-RS set, and RS set may be interchangeably read.

[0174] If the UE is not provided with q0 by the failure detection resources (failureDetectionResources) for one of the BWPs of its serving cell, the UE determines the RS (set q0) to use for the BFD procedure according to the following implicit BFD-RS determination procedure:

[0175] [Implicit BFD-RS Decision Procedure] The UE determines to include in set q0 P-CSI-RS resource configuration indices that have the same value as the RS indices in the RS set indicated by the TCI state (TCI-State) for the corresponding CORESET that the UE uses to monitor the PDCCH. If there are two RS indices in one TCI state, set q0 includes RS indices that have a QCL type D configuration for the corresponding TCI state. The UE assumes that set q0 includes up to two RS indices. The UE assumes single-port RSs in set q0.

[0176] This set q0 may be called the implicit BFD-RS.

[0177] In this way, the UE determines the BFD-RS (RS set) according to the TCI state for the PDCCH. The UE assumes that the RS set includes up to two RSs.

[0178] (analysis) As mentioned above, in the unified TCI framework, the common / unified TCI state can be updated by the DCI.

[0179] Also, as mentioned above, based on Rel. 16, if the RLM / BFD RS is not configured, the RLM / BFD RS is implicitly derived from the QCL of the CORESET (QCL Type D RS if multiple (e.g., two) TCI states are configured).

[0180] Generally, the monitoring RS for RLM / BFD (RLM / BFD RS) is determined / selected at the L2 or L3 level rather than by L1 dynamic signaling.

[0181] In Rel.15 / 16, the update / switch of the RLM / BFD RS is not done by DCI, but can only be done by MAC CE using the implicit method above, or by RRC using either the implicit or explicit method above.

[0182] In Rel. 17 and later, the monitoring RS for RLM / BFD (RLM / BFD RS) is at least one of the TCI states indicated by the DCI and the TCI state activated by the MAC CE, and it is considered that one of the TCI states is applied to the CORESET by dynamic signaling.

[0183] In addition, it is being considered to introduce MAC CE to explicitly update RLM / BFD RS in Rel.17 and later. In this case, it is thought that the implicit derivation of RLM / BFD RS as described above will no longer be necessary.

[0184] However, in the unified TCI framework in CA, it is unclear which RS is used for RLM / BFD. For example, when the implicit RLM-RS determination procedure described above is used, it is unclear whether the RS used for RLM / BFD (RLM / BFD RS) in DCI can be set / indicated / updated.

[0185] If the RS used in RLM / BFD is unclear, the accuracy of RLM / BFD may deteriorate, resulting in degradation of communication quality, throughput, etc.

[0186] Therefore, the present inventors have conceived a method for setting / updating an RS used in RLM / BFD when a common TCI state is set.

[0187] 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.

[0188] In the present disclosure, "A / B / C" and "at least one of A, B, and C" may be read as interchangeable. In the present disclosure, cell, serving cell, CC, carrier, BWP, DL BWP, UL BWP, active DL BWP, active UL BWP, and band may be read as interchangeable. In the present disclosure, index, ID, indicator, and resource ID may be read as interchangeable. In the present disclosure, support, control, controllable, operate, and operable may be read as interchangeable.

[0189] In the present disclosure, the terms configure, activate, update, indicate, enable, specify, and select may be read interchangeably.

[0190] 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. In the present disclosure, RRC, RRC signaling, RRC parameters, higher layer, higher layer parameters, RRC information elements (IEs), and RRC messages may be interchangeable.

[0191] 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.

[0192] In the present disclosure, MAC CE and activation / deactivation command may be read interchangeably.

[0193] In the present disclosure, the terms pool, set, group, list, and candidate may be read interchangeably.

[0194] In the present disclosure, DMRS, DMRS port, and antenna port may be read interchangeably.

[0195] In the present disclosure, the terms special cell, SpCell, PCell, and PSCell may be read interchangeably.

[0196] In this disclosure, the terms beam, spatial-domain filter, spatial setting, TCI state, UL TCI state, unified TCI state, unified beam, common TCI state, common beam, TCI assumption, QCL assumption, QCL parameter, spatial-domain receive filter, UE spatial-domain receive filter, UE receive beam, DL beam, DL receive beam, DL precoding, DL precoder, DL-RS, RS for QCL type D in TCI state / QCL assumption, RS for QCL type A in TCI state / QCL assumption, spatial relationship, spatial-domain transmit filter, UE spatial-domain transmit filter, UE transmit beam, UL beam, UL transmit beam, UL precoding, UL precoder, and PL-RS may be interchangeable. In this disclosure, the terms QCL type X-RS, DL-RS associated with QCL type X, DL-RS with QCL type X, source of DL-RS, SSB, CSI-RS, and SRS may be interchangeable.

[0197] In the present disclosure, common beam, common TCI, common TCI state, unified TCI, unified TCI state, TCI state applicable to DL and UL, TCI state applicable to multiple (multiple types) channels / RS, TCI state applicable to multiple types of channels / RS, and PL-RS may be read interchangeably.

[0198] In the present disclosure, the terms multiple TCI states configured by RRC, multiple TCI states activated by MAC CE, pool, TCI state pool, active TCI state pool, common TCI state pool, joint TCI state pool, separate TCI state pool, common TCI state pool for UL, common TCI state pool for DL, common TCI state pool configured / activated by RRC / MAC CE, and TCI state information may be read interchangeably.

[0199] In the present disclosure, the terms CC list, serving cell list, CC list in cell group configuration (CellGroupConfig), applicable list, simultaneous TCI update list / second simultaneous TCI update list, simultaneousTCI-UpdateList1-r16 / simultaneousTCI-UpdateList2-r16, simultaneous TCI cell list, simultaneousTCI-CellList, simultaneous spatial update list / second simultaneous spatial update list, simultaneousSpatial-UpdatedList1-r16 / simultaneousSpatial-UpdatedList2-r16, configured CC, configured list, BWP / CC in the configured list, all BWP / CC in the configured list, CC indicated by the activation command, indicated CC, CC that received MAC CE, and information indicating multiple cells for updating at least one of TCI state and spatial relationship may be read as interchangeable.

[0200] In the present disclosure, expressions such as "TCI state A is QCL type D, which is the same as TCI state B," "TCI state A is the same as TCI state B," and "TCI state A is QCL type D with TCI state B" may be read interchangeably.

[0201] In the present disclosure, the terms CSI-RS, NZP-CSI-RS, periodic (P)-CSI-RS, P-TRS, semi-persistent (SP)-CSI-RS, aperiodic (A)-CSI-RS, TRS, tracking CSI-RS, CSI-RS having TRS information (higher layer parameter trs-Info), NZP CSI-RS resource in an NZP CSI-RS resource set having TRS information, NZP-CSI-RS resource in an NZP-CSI-RS resource set consisting of multiple NZP-CSI-RS resources of the same antenna port, and TRS resource may be interchangeable. In the present disclosure, the terms CSI-RS resource, CSI-RS resource set, CSI-RS resource group, and information element (IE) may be interchangeable.

[0202] In the present disclosure, the terms panel, Uplink (UL) transmitting entity, TRP, spatial relationship, control resource set (CORESET), PDSCH, codeword, base station, antenna port of a certain signal (e.g., Demodulation Reference Signal (DMRS) port), antenna port group of a certain signal (e.g., DMRS port group), group for multiplexing (e.g., Code Division Multiplexing (CDM) group, reference signal group, CORESET group), CORESET pool, CORESET subset, CW, redundancy version (RV), and layer (MIMO layer, transmission layer, spatial layer) may be interchangeable. Also, panel identifier (ID) and panel may be interchangeable. In the present disclosure, the terms TRP ID, TRP related ID, CORESET pool index, the position of one of two TCI states corresponding to one code point in a field in a DCI (ordinal number, first TCI state or second TCI state), and TRP may be read interchangeably.

[0203] In the present disclosure, the terms TRP, transmission point, panel, DMRS port group, CORESET pool, and one of two TCI states associated with one code point in a TCI field may be read interchangeably.

[0204] In this disclosure, the terms "single TRP," "single TRP system," "single TRP transmission," and "single PDSCH" may be interchangeable. In this disclosure, the terms "multiple TRP," "multiple TRP system," "multiple TRP transmission," and "multiple PDSCH" may be interchangeable. In this disclosure, the terms "single DCI," "single PDCCH," "multiple TRP based on a single DCI," and "activating two TCI states on at least one TCI codepoint" may be interchangeable.

[0205] In the present disclosure, single TRP, channel using single TRP, channel using one TCI state / spatial relationship, no multi-TRP enabled by RRC / DCI, no multiple TCI states / spatial relationships enabled by RRC / DCI, no CORESETPoolIndex value of 1 set for any CORESET, and no codepoint in the TCI field mapped to two TCI states may be read interchangeably.

[0206] In the present disclosure, "multi-TRP," "channel using multi-TRP," "channel using multiple TCI states / spatial relationships," "multi-TRP being enabled by RRC / DCI," "multiple TCI states / spatial relationships being enabled by RRC / DCI," and "at least one of multi-TRP based on a single DCI" and "multi-TRP based on multiple DCI" may be interchangeable. In the present disclosure, "multi-TRP based on multiple DCI," and "setting a CORESET pool index (CORESETPoolIndex) value of 1 for the CORESET" may be interchangeable. In the present disclosure, "multi-TRP based on a single DCI," and "at least one code point in the TCI field is mapped to two TCI states" may be interchangeable.

[0207] In the present disclosure, TRP#1 (first TRP) may correspond to CORESET pool index=0 or may correspond to the first of two TCI states corresponding to one code point in the TCI field. TRP#2 (second TRP) may correspond to CORESET pool index=1 or may correspond to the second of two TCI states corresponding to one code point in the TCI field.

[0208] In the present disclosure, CORESET0, a CORESET having index 0, and a common CORESET may be read interchangeably.

[0209] In this disclosure, the terms target, application, and destination may be interchangeable. In this disclosure, the terms QCL source, source, and reference may be interchangeable.

[0210] (Wireless communication method) In the present disclosure, DL TCI, DL common TCI, DL unified TCI, common TCI, and unified TCI may be interchangeable. In the present disclosure, UL TCI, UL common TCI, UL unified TCI, common TCI, and unified TCI may be interchangeable.

[0211] In the present disclosure, in the case of a joint TCI pool, "when a joint TCI pool is configured" and "when a separate TCI pool is configured" may be read interchangeably.

[0212] In the present disclosure, the terms "a joint TCI pool is configured," "the TCI pool configured for DL ​​and the TCI pool configured for UL are common," "a TCI pool for both DL and UL is configured," and "one TCI pool (one set of TCIs) is configured" may be read interchangeably.

[0213] In the present disclosure, the following terms may be interchangeable: a separate TCI pool is configured; a TCI pool configured for DL ​​and a TCI pool configured for UL are different; a TCI pool for DL ​​(first TCI pool, first TCI set) and a TCI pool for UL (second TCI pool, second TCI set) are configured; multiple TCI pools (multiple sets of TCIs) are configured; and a TCI pool for DL ​​is configured. When a TCI pool for DL ​​is configured, the TCI pool for UL may be equal to the configured TCI pool.

[0214] In the present disclosure, the channels / RS to which the common TCI is applied may be PDSCH / HARQ-ACK information / PUCCH / PUSCH / CSI-RS / SRS.

[0215] In the present disclosure, the CC / BWP to which the unified TCI state applies, the target to which the unified TCI state applies, and the target to which the unified TCI state applies may be read interchangeably.

[0216] In the present disclosure, the first QCL type and QCL type A may be interchangeable, and the second QCL type and QCL type D may be interchangeable.

[0217] In each embodiment of the present disclosure, a pool including a plurality of unified TCI states may be configured / activated for a UE, and one or more of the plurality of unified TCI states may be indicated to the UE. The configuration / activation may be performed by configuration information transmitted via higher layer signaling (e.g., RRC signaling / MAC CE). The indication may be performed by indication information transmitted using DCI.

[0218] In addition, in the present disclosure, signaling configuration, signaling, setting, configuration, setting information, instruction, instruction information, etc. may be read interchangeably.

[0219] In the present disclosure, BFR, BFR configuration, BFR procedure, BFD, BFD procedure, BFD-RS, BFD-RS configuration, RLM, RLM configuration, RLM procedure, RLM-RS, and RLM-RS configuration may be interchangeable. In the present disclosure, per cell BFR, cell-specific BFR, and Rel. 15 / 16 BFR may be interchangeable. In the present disclosure, per TRP BFR, TRP-specific BFR, and Rel. 17 / Rel. 17 and later BFR may be interchangeable.

[0220] First Embodiment The RLM / BFD RS may be indicated using L1 signaling (e.g., DCI). The UE may be instructed of the RLM / BFD RS using L1 signaling (e.g., DCI). If the RLM / BFD RS is not configured, the UE may derive the RLM / BFD RS according to the method described in at least one of the following embodiments 1-1 and 1-2.

[0221] <<Embodiment 1-1>> The UE may derive the RLM / BFD RS from the QCL assumptions / TCI state of the CORESET.

[0222] The CORESET may be determined based on at least one of the CORESET monitoring period, monitoring slot, and CORESET ID, similar to RLM / BFD in Rel.15.

[0223] For example, the CORESET may be the CORESET with the smallest CORESET ID in the latest monitoring slot, or the CORESET with the largest CORESET ID in the shortest monitoring period.

[0224] In the present disclosure, the terms "shortest" and "longest" may be interchangeable, and the terms "minimum" and "maximum" may be interchangeable.

[0225] If the CORESET applies to a common / unified TCI state, the UE may decide / determine to use the common / unified TCI state as the RLM / BFD RS.

[0226] If the common / unified TCI state is indicated by the DCI, the UE may decide / determine to use the common / unified TCI state as the RLM / BFD RS, i.e., the UE may be indicated the RLM / BFD RS using the DCI.

[0227] The DCI may be at least one of a DCI format with DL assignment including an existing TCI field (specified up to Rel. 15 / 16), a DCI format without DL assignment including an existing TCI field, a DCI format without DL assignment including a new TCI field (specified from Rel. 17 onwards), and a new DCI format including a new TCI field.

[0228] In the present disclosure, a DCI (DCI format) that does not indicate scheduling of either a PDSCH or a PUSCH, a DCI (DCI format) that does not indicate scheduling of a PDSCH, a DCI (DCI format) without a DL assignment, a DCI (DCI format) that is a DCI format for a DL assignment and does not schedule a PDSCH, a DCI (DCI format) that has a field for a DL assignment and does not schedule a PDSCH, and a DCI (DCI format) that includes a TCI field and does not schedule a PDSCH may be interchangeable. DCI formats with / without a DL assignment may be DCI format 1_1 / 1_2, for example. A new DCI format may be represented by DCI format X_Y (X and Y are arbitrary numbers). Furthermore, the new TCI field may be a field that reuses an unused field from among fields used for existing PDSCH scheduling, or may be a field not specified in Rel. 15 / 16.

[0229] In addition, when multiple RSs (e.g., QCL type A RS and QCL type D RS) are configured within one TCI state, the UE may determine / decide to use an RS of a specific QCL type (e.g., QCL type D RS).

[0230] Embodiment 1-2 The UE may derive the RLM / BFD RS from the QCL assumption / TCI state of the common / unified TCI state.

[0231] For example, when N=M=1 (i.e., when a joint TCI state for a single TRP is configured / indicated), the UE may determine / decide to use the indicated joint TCI state as the RLM / BFD RS.

[0232] Also, for example, when N=1 and M=1 (i.e., when separate TCI states for a single TRP are configured / indicated), the UE may determine / decide to use the indicated DL TCI state (or UL TCI state) as the RLM / BFD RS.

[0233] Also, for example, when N=M>1 (i.e., when multiple sets of joint TCI states for multiple TRPs are configured / instructed), for RLM and per-cell BFR, the UE may determine / decide to use one TCI state from any of the multiple sets of joint TCI states as the RLM / BFD RS.

[0234] The one TCI state may be, for example, a TCI state of an index in the set of minimum (first) / maximum (last) TCI states, a TCI state associated with the set of minimum (first) / maximum (last), a TCI state associated with the minimum (first) / maximum (last) CORESET ID / TRP ID, or a TCI state associated with the minimum (first) / maximum (last) TCI state ID.

[0235] Also, for example, when N=M>1, for BFR per TRP, the UE may determine / decide to use a total of X TCI states, one from each of multiple (e.g., X) sets of joint TCI states, as the BFD RS. For example, the UE may determine / decide to use a total of two TCI states corresponding to two TRPs as the BFD RS. The UE may assume that a TCI state is indicated by a DCI for each set of joint TCI states.

[0236] Also, for example, when N>1 and M>1 (i.e., when separate TCI state sets for multiple TRPs are configured / instructed), for RLM and per-cell BFR, the UE may determine / decide to use one DL TCI state (or UL TCI state) from any of the multiple separate TCI state sets as the RLM / BFD RS. The one DL TCI state (or UL TCI state) may be the TCI state associated with the smallest (first) / largest (last) CORESET ID / TRP ID, or the TCI state of the smallest (first) / largest (last) single joint TCI state index.

[0237] In addition, when multiple RSs (e.g., QCL type A RS and QCL type D RS) are configured within one TCI state, the UE may determine / decide to use an RS of a specific QCL type (e.g., QCL type D RS).

[0238] Embodiments 1-3 A period / timeline / required time between sending / receiving a TCI indication and (starting) measuring / performing RLM / BFD may be specified, which may be a minimum period / minimum period gap between sending / receiving a TCI indication and (starting) measuring / performing RLM / BFD.

[0239] The timing of RLM / BFD measurement / implementation (start) may be read as the timing of updating / changing / setting RLM / BFD RS.

[0240] The period may be specified in advance in a specification, may be configured in the UE by higher layer signaling, or may be reported to the network (NW, for example, a base station) as a UE capability.

[0241] Furthermore, the period may be indicated in a specific time unit (e.g., symbol) (e.g., x symbols) or may be indicated as absolute time (e.g., y ms). Furthermore, the period may be set differently for each subcarrier spacing (setting), or may be set commonly for different subcarrier spacings (settings).

[0242] Fig. 10 is a diagram illustrating an example of updating the RLM / BFD RS according to embodiments 1 to 3. In the example illustrated in Fig. 10, the UE receives a beam instruction DCI as a TCI instruction. The UE applies the TCI state indicated by the beam instruction DCI as the RLM / BFD RS. The UE updates the RLM / BFD RS after a specific period (referred to as a minimum period gap) has elapsed since the end of reception of the beam instruction DCI.

[0243] In this embodiment, a specific field included in at least one of a DCI format defined in Rel. 17 or later and a DCI format without DL assignment (e.g., DCI format 1_1 / 1_2) may be used to indicate the RLM / BFD RS. The specific field may be an unused field in the DCI format. This "unused field" may be a field used for DL ​​assignment. When the RLM / BFD RS is indicated to the UE by an unused field in the DCI format, the name of the field may not be changed, or may be changed to the name of a field for indicating the RLM / BFD RS. By using such a field, the RLM / BFD RS can be explicitly indicated to the UE.

[0244] According to the first embodiment described above, it becomes possible to dynamically update / configure / indicate the RLM / BFD RS using DCI in the unified / common TCI framework.

[0245] <Second embodiment> The RLM / BFD RS may not be explicitly indicated using L1 signaling (e.g., DCI). The UE may not be explicitly indicated the RLM / BFD RS using L1 signaling (e.g., DCI). If the RLM / BFD RS is not configured, the UE may derive the RLM / BFD RS according to the method described in at least one of the following embodiments 2-1 and 2-2.

[0246] <<Embodiment 2-1>> The UE may derive the RLM / BFD RS from the QCL assumptions / TCI state of the CORESET.

[0247] The CORESET may be determined based on at least one of the CORESET monitoring period, monitoring slot, and CORESET ID, similar to RLM / BFD in Rel.15.

[0248] For example, the CORESET may be the CORESET with the smallest CORESET ID in the latest monitoring slot, or the CORESET with the largest CORESET ID in the shortest monitoring period.

[0249] If the CORESET applies to a common / unified TCI state, the UE may decide / determine to use the common / unified TCI state as the RLM / BFD RS.

[0250] If the common / unified TCI state is indicated by the DCI, the UE may not use the common / unified TCI state as the RLM / BFD RS. The UE may determine / decide to use the QCL assumption / TCI state of the CORESET corresponding to the TCI state not indicated by the DCI as the RLM / BFD RS.

[0251] The DCI may be at least one of a DCI format with DL assignment including an existing TCI field (specified up to Rel. 15 / 16), a DCI format without DL assignment including an existing TCI field, a DCI format without DL assignment including a new TCI field (specified from Rel. 17 onwards), and a new DCI format including a new TCI field.

[0252] <<Embodiment 2-2>> The UE may derive the RLM / BFD RS from the QCL assumption / TCI state of the common / unified TCI state.

[0253] [Embodiment 2-2-1] When a joint TCI pool for UL and DL is applied, the UE may determine / decide to use any joint TCI state (active joint TCI state) in the joint TCI pool as the RLM / BFD RS.

[0254] The joint TCI state used as the RLM / BFD RS may be, for example, a joint TCI state (active joint TCI state) corresponding to the smallest (first) / largest (last) joint TCI state ID in the joint TCI pool, or a joint TCI state corresponding to the smallest (first) / largest (last) code point in the TCI field for indicating the joint TCI state. This TCI field may be a TCI field included in an existing DCI format (here, DCI format 1_1 / 1_2 with DL assignment) as shown in FIG. 11B, or may be a new field in a new DCI format. Furthermore, this TCI field may be a field used to indicate a separate DL TCI state, or may be a field used to indicate a joint TCI state.

[0255] 11A is a diagram illustrating an example of determination of an RLM / BFD RS according to embodiment 2-2-1. In FIG. 11A, the setting of a common TCI state for UL and DL by the RRC and the activation of the common TCI state for UL and DL by the MAC CE are the same as those in FIG. 2A.

[0256] In the example shown in FIG. 11A, the UE determines / decides to use one joint TCI state among the UL and DL common TCI states activated in the MAC CE as the RLM / BFD RS.

[0257] 11B is a diagram showing another example of determining an RLM / BFD RS according to embodiment 2-2-1. In the example shown in Fig. 11B, the UE determines / decides to use the TCI state (TCI state #1) corresponding to the smallest code point (0000) as the RLM / BFD RS based on the association (list / table) between the code points in the TCI field and the TCI states in the joint TCI pool.

[0258] [Embodiment 2-2-2] When separate TCI pools for UL and DL are applied, the UE may determine / decide to use any of the DL TCI states (active DL TCI states) (or UL TCI states (active UL TCI states)) in the separate TCI pool as the RLM / BFD RS.

[0259] The DL TCI state used as the RLM / BFD RS may be, for example, a DL TCI state (active TCI state) corresponding to the smallest (first) / largest (last) TCI state ID in a DL TCI pool (DL TCI), or a DL TCI state corresponding to the smallest (first) / largest (last) code point in a TCI field for indicating the DL TCI state. This TCI field may be, for example, a TCI field (existing TCI field) included in an existing DCI format (here, DCI format 1_1 / 1_2 with DL assignment) as shown in FIG. 13, or may be a new field in a new DCI format. Furthermore, this TCI field may be a field used to indicate a separate DL TCI state, or may be a field used to indicate a joint TCI state.

[0260] The UL TCI status may be, for example, a UL TCI status (active TCI status) corresponding to the smallest (first) / largest (last) UL TCI status ID in a UL TCI pool (UL TCI), or a UL TCI corresponding to the smallest (first) / largest (last) codepoint of a TCI field for indicating the UL TCI status. This TCI field may be a new field (e.g., a UL TCI field) in a new DCI format, as shown in Figure 13. The new DCI format may include a field for the DL TCI status or the joint TCI status and a field for the UL TCI status.

[0261] Fig. 12 is a diagram showing an example of determination of an RLM / BFD RS according to embodiment 2-2-2. In Fig. 12, a TCI state (TCI state pool) for UL and a TCI state (TCI state pool) for DL ​​are set. The UL TCI state and DL TCI state are set by the RRC, and the UL TCI state and DL TCI state are activated by the MAC CE.

[0262] In the example shown in FIG. 12, the UE judges / decides to use one of the DL TCI states activated by the MAC CE as the RLM / BFD RS.

[0263] 13 is a diagram showing another example of determining an RLM / BFD RS according to embodiment 2-2-2. In the example shown in Fig. 13, the UE determines / decides to use the TCI state (TCI state #1) corresponding to the smallest code point (0000) as the RLM / BFD RS based on the association (list / table) between the code point of the TCI field for the DL TCI state and the TCI state in the DL TCI pool.

[0264] The DCI format shown in FIG. 13 may be a DCI format defined in Rel. 17 or later or a DCI format without DL assignment (for example, DCI format 1_1 / 1_2).

[0265] According to the second embodiment described above, it is possible to update / configure / indicate the RLM / BFD RS without using DCI in the unified / common TCI framework.

[0266] <Third embodiment> The RLM / BFD RS may be indicated / updated using the MAC CE. The UE may indicate / update the RLM / BFD RS using the MAC CE.

[0267] <Embodiment 3-1> The MAC CE used to indicate / update the RLM / BFD RS may include multiple bit fields indicating RS IDs (a list of multiple RS IDs). The UE may determine / decide the RLM / BFD RS to be updated based on the bit fields indicating the multiple RS IDs.

[0268] The MAC CE may include at least one of a bit field indicating a BWP ID, a bit field indicating a serving cell ID, a bit field indicating an RS ID (e.g., a CSI-RS ID / SSB ID), and a field indicating whether the MAC CE is used for RLM or BFD.

[0269] The UE may configure the multiple RS IDs (which may also be referred to as a list of RS IDs) included in the MAC CE in the RRC or may implicitly derive them from multiple (e.g., all) SSB IDs.

[0270] The bit field indicating the RS ID may be a bitmap indication indicating the RS ID of the RS to be used as the RLM / BFD RS. For example, when the bit field indicating the RS ID indicates a first value (e.g., 0), the UE may determine not to use the RS corresponding to the RS ID as the RLM / BFD RS. Also, when the bit field indicating the RS ID indicates a second value (e.g., 1), the UE may determine to use the RS corresponding to the RS ID as the RLM / BFD RS.

[0271] Alternatively, the MAC CE may not include a field indicating whether the MAC CE is used for RLM or BFD, in which case the UE may determine that the MAC CE is used to update / indicate at least one of the RLM RS and the BFD RS.

[0272] The MAC CE may also include a bit field indicating the TRP ID / CORESET ID for BFR of multiple TRPs.

[0273] 14 is a diagram illustrating an example of a MAC CE according to embodiment 3-1. The MAC CE illustrated in FIG. 14 includes a bit field indicating a BWP ID, a bit field indicating a serving cell ID, and a bit field indicating a CSI-RS ID / SSB ID (T n and a field (denoted as P) indicating whether the MAC CE is used for RLM or BFD.

[0274] In addition, when the BFD / RLM RS is explicitly updated using the MAC CE as described in this embodiment, the first and second embodiments may not be applied. In this case, the UE may assume that the BFD / RLM RS is updated by the MAC CE.

[0275] <Embodiment 3-2> The MAC CE used to indicate / update the RLM / BFD RS may include multiple bit fields indicating RS IDs (a list of multiple RS IDs). The UE may determine / decide the RLM / BFD RS to be updated based on the bit fields indicating the multiple RS IDs.

[0276] The MAC CE may include at least one of a bit field indicating a BWP ID, a bit field indicating a serving cell ID, a bit field indicating an RS ID (e.g., a CSI-RS ID / SSB ID), and a field indicating whether the MAC CE is used for RLM or BFD.

[0277] The UE may configure the multiple RS IDs (which may also be referred to as a list of RS IDs) included in the MAC CE in the RRC or may implicitly derive them from multiple (e.g., all) SSB IDs.

[0278] The bit field indicating the RS ID may be a field indicating the RS ID of the RS to be used as the RLM / BFD RS.

[0279] Alternatively, the MAC CE may not include a field indicating whether the MAC CE is used for RLM or BFD, in which case the UE may determine that the MAC CE is used to update / indicate at least one of the RLM RS and the BFD RS.

[0280] The MAC CE may also include a bit field indicating the TRP ID / CORESET ID for BFR of multiple TRPs.

[0281] Fig. 15 is a diagram illustrating an example of a MAC CE according to embodiment 3-2. The MAC CE illustrated in Fig. 15 includes a bit field indicating a BWP ID, a bit field indicating a serving cell ID, a bit field indicating a CSI-RS ID / SSB ID (denoted as RS ID(n)), and a field (denoted as P) indicating whether the MAC CE is used for RLM or BFD.

[0282] 14 and 15 are merely examples, and the fields included in the MAC CE, the number of bits in each field, and the arrangement of each field are not limited to these. These MAC CEs may include reserved bits.

[0283] According to the configuration of the MAC CE of embodiment 3-2, the number of RS IDs can be reduced compared to the configuration of the MAC CE of embodiment 3-1, and the signaling overhead of the MAC CE can be reduced.

[0284] <Embodiment 3-3> The MAC CE used to indicate / update the RLM / BFD RS may include information about the new beam candidate RS for BFR (embodiment 3-3-1). The information about the new beam candidate RS for BFR may be a list including one or more new beam candidate RS for BFR.

[0285] In this case, in addition to / instead of the fields described in the above-mentioned embodiments 3-1 and 3-2, a field indicating a new beam candidate RS for BFR may be included.

[0286] The field indicating whether the MAC CE is used for either RLM or BFD, as described in the above embodiments 3-1 and 3-2, may be read as a field indicating whether the MAC CE indicates an RLM / BFD RS or a new beam candidate RS.

[0287] Furthermore, since the number of new beam candidate RSs is generally large (e.g., 32, 64) (compared to the number of RLM / BFD RSs), it is preferable for embodiment 3-3-1 to utilize the MAC CE configuration described in embodiment 3-1 above.

[0288] In addition, a MAC CE including information about new beam candidate RSs for BFR may be defined separately from the MAC CE used to indicate / update the RLM / BFD RS (embodiment 3-3-2).

[0289] This embodiment is suitable for updating a new beam candidate RS in consideration of the complexity of the UE, for example, when the physical location of the UE is changed.

[0290] According to the third embodiment described above, it becomes possible to update / configure / instruct the RLM / BFD RS using the MAC CE in the unified / common TCI framework.

[0291] <Fourth embodiment> An upper layer parameter (RRC IE) / UE capability corresponding to a function (feature) in at least one of the above embodiments may be defined. The UE capability may indicate that the function is supported.

[0292] A UE configured with higher layer parameters corresponding to the function (enabling the function) may perform the function. It may also be specified that "a UE not configured with higher layer parameters corresponding to the function shall not perform the function (for example, in accordance with Rel. 15 / 16)."

[0293] A UE that reports a UE capability indicating that it supports the function may perform the function. It may also be specified that "a UE that does not report a UE capability indicating that it supports the function shall not perform the function (e.g., in accordance with Rel. 15 / 16)."

[0294] If the UE reports a UE capability indicating that it supports the function and the corresponding upper layer parameter is configured, the UE may perform the function. It may also be specified that "if the UE does not report a UE capability indicating that it supports the function or if the corresponding upper layer parameter is not configured, the UE shall not perform the function (e.g., in accordance with Rel. 15 / 16)."

[0295] The UE capability may indicate whether the UE supports this feature.

[0296] The function may be a unified TCI state framework in a CA or a unified TCI state framework applied to multiple CC / BWPs.

[0297] The UE capability may be defined as whether it supports at least one of the following: a unified TCI state framework, joint / separate TCI pools, and joint / separate beam direction.

[0298] The UE capability may be defined by the number of TCI states configured by the RRC for common beam direction that the UE supports. Common beam direction may be interchangeably read as UL separate beam direction and DL separate beam direction. Also, common beam direction may be interchangeably read as at least one of common beam direction, UL separate beam direction, and DL separate beam direction.

[0299] The UE capability may be defined by the number of active TCI states for common beam direction that the UE supports. Common beam direction may be interchangeably referred to as UL separate beam direction and DL separate beam direction. Also, common beam direction may be interchangeably referred to as at least one of common beam direction, UL separate beam direction, and DL separate beam direction.

[0300] The UE capabilities may be defined as N and / or M that the UE supports.

[0301] UE capability may be defined by whether the TCI state is indicated by the DCI. For example, UE capability may be defined by whether the UE supports the common TCI state being indicated by at least one of the new DCI format and the DCI format without DL assignment (DCI format 1_1 / 1_2).

[0302] The UE capability may be defined as whether the RLM / BFD RS can be selected / determined by DCI (e.g., beam indication DCI) (first embodiment).

[0303] The UE capability may be defined as whether the RLM / BFD RS can be selected / determined from the active TCI pool (second embodiment).

[0304] The UE capability may be defined by whether the RLM / BFD RS can be updated / determined by the MAC CE (third embodiment). Also, the UE capability may be defined by the number of RLM / BFD RSs that can be updated / determined by the MAC CE.

[0305] According to the fourth embodiment, the UE can achieve the above functions while maintaining compatibility with existing specifications.

[0306] (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.

[0307] 16 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).

[0308] 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.

[0309] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the 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.

[0310] 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 the SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0311] 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.

[0312] 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 (CC) and dual connectivity (DC).

[0313] 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 above 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 be a frequency band higher than FR2.

[0314] 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.

[0315] The multiple base stations 10 may be connected by wire (for example, optical fiber conforming to the Common Public Radio Interface (CPRI), an X2 interface, or the like) or wirelessly (for example, 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.

[0316] 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.

[0317] The user terminal 20 may be a terminal compatible with at least one of communication methods such as LTE, LTE-A, and 5G.

[0318] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the radio 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).

[0319] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0320] 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.

[0321] 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)), etc. may be used as an uplink channel.

[0322] The PDSCH transmits user data, higher layer control information, System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit Master Information Block (MIB).

[0323] 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.

[0324] 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 an UL grant, a UL DCI, etc. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

[0325] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources to search 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 a CORESET associated with a certain search space based on the search space configuration.

[0326] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be called a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in the present disclosure may be read interchangeably.

[0327] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), acknowledgement 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.

[0328] 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.

[0329] 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, 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 as DL-RS.

[0330] 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 the SS (PSS, SSS) and the PBCH (and 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 reference signals.

[0331] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. 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).

[0332] (base station) 17 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.

[0333] 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.

[0334] 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.

[0335] 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 to be transmitted as signals, control information, sequences, etc., 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.

[0336] 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.

[0337] The transmitting / receiving unit 120 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 1211 and an RF unit 122. The receiving unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0338] 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 pertains, such as an array antenna.

[0339] 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.

[0340] The transceiver 120 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0341] The transceiver 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.

[0342] The transceiver 120 (transmission processor 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.

[0343] The transmitting / receiving unit 120 (RF unit 122) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna .

[0344] On the other hand, the transmitting / receiving unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna .

[0345] 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.

[0346] 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.

[0347] 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.

[0348] 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.

[0349] The transceiver 120 may transmit information indicating a plurality of transmission configuration indication (TCI) states applicable to a plurality of types of channels in one or more cells, and may transmit at least one of a Medium Access Control (MAC) control element indicating one or more TCI states of the plurality of TCI states, a first reference signal for a Radio Link Monitoring (RLM) procedure, and a second reference signal for a Beam Failure Detection (BFD) procedure, and downlink control information (DCI) indicating one or more TCI states of the plurality of TCI states. When at least one of the first reference signal and the second reference signal is not configured by a Radio Resource Control (RRC) information element, the control unit 110 may indicate at least one of the first reference signal and the second reference signal using either the MAC CE or the DCI (first to third embodiments).

[0350] (user terminal) 18 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.

[0351] Note that this example mainly shows functional blocks of the characteristic parts of the present embodiment, 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.

[0352] 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, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0353] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also 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.

[0354] 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 from 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.

[0355] 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.

[0356] The transmitting / receiving antenna 230 can be configured as an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0357] 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.

[0358] The transceiver 220 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0359] The transceiver 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.

[0360] The transceiver 220 (transmission processor 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.

[0361] 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 when transform precoding is not enabled, the transceiver unit 220 may not perform DFT processing as the transmission processing.

[0362] The transmitting / receiving unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna 230.

[0363] On the other hand, the transmitting / receiving unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna 230.

[0364] The transceiver 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 to acquire user data, etc.

[0365] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurement, CSI measurement, 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.

[0366] 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, the transmitting / receiving antenna 230, and the transmission path interface 240.

[0367] The transceiver unit 220 may receive information indicating a plurality of transmission configuration indication (TCI) states applicable to a plurality of types of channels in one or more cells, and may receive at least one of a Medium Access Control (MAC) control element indicating one or more TCI states among the plurality of TCI states, a first reference signal for a Radio Link Monitoring (RLM) procedure, and a second reference signal for a Beam Failure Detection (BFD) procedure, and downlink control information (DCI) indicating one or more TCI states among the plurality of TCI states. When at least one of the first reference signal and the second reference signal is not configured by a Radio Resource Control (RRC) information element, the control unit 210 may determine at least one of the first reference signal and the second reference signal based on either the MAC CE or the DCI (first to third embodiments).

[0368] The DCI may indicate a TCI state common to both uplink and downlink. The control unit 210 may use the TCI state common to both uplink and downlink indicated by the DCI as at least one of the first reference signal and the second reference signal (first embodiment).

[0369] The DCI may indicate the uplink TCI state and the downlink TCI state separately. The control unit 210 may use the downlink TCI state indicated by the DCI as at least one of the first reference signal and the second reference signal (first embodiment).

[0370] The control unit 210 may use the TCI state corresponding to the smallest TCI state ID in the information indicating the plurality of TCI states as at least one of the first reference signal and the second reference signal (second embodiment).

[0371] (Hardware configuration) 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 also be realized by combining the single device or multiple devices with software.

[0372] 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 mentioned above, the implementation method of each is not particularly limited.

[0373] 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. 19 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.

[0374] In this disclosure, terms such as apparatus, circuit, device, section, unit, etc. may be read 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.

[0375] 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.

[0376] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading predetermined 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.

[0377] 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), transmission / reception unit 120 (220), etc. may be realized by the processor 1001.

[0378] 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 realized by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be realized in a similar manner.

[0379] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, a cache, a main memory, or the like. The memory 1002 may store executable programs (program codes), software modules, and the like for implementing a wireless communication method according to an embodiment of the present disclosure.

[0380] Storage 1003 is a computer-readable recording medium and may be constituted by 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, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as a secondary storage device.

[0381] 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.

[0382] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0383] 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.

[0384] 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 such hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0385] (Variation) Note that terms explained 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.

[0386] 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.

[0387] 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, a subcarrier spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a transmission time interval (TTI), the number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transceiver in the frequency domain, and a specific windowing process performed by a transceiver in the time domain.

[0388] A slot may be composed of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol), and may be a time unit based on numerology.

[0389] 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.

[0390] 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.

[0391] 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 a subframe and a 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.

[0392] 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. However, the definition of TTI is not limited to this.

[0393] 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.

[0394] 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.

[0395] 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.

[0396] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0397] 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 also be determined based on numerology.

[0398] 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. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0399] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0400] 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.

[0401] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0402] The BWP may include an UL BWP (a BWP for UL) and a DL BWP (a BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0403] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0404] 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.

[0405] 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.

[0406] 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.

[0407] 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.

[0408] 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.

[0409] 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.

[0410] Notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, 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.

[0411] Note that the physical layer signaling may be called 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 called 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).

[0412] 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).

[0413] 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).

[0414] 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.

[0415] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0416] 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).

[0417] 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.

[0418] In this 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.

[0419] 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 divided 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 term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0420] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0421] 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.

[0422] At least one of the base station and the mobile station may be called 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 object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may 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.

[0423] 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, "sidelink"). For example, terms such as uplink channel and downlink channel may be read as sidelink channel.

[0424] 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.

[0425] 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) and a Serving-Gateway (S-GW)), or a combination thereof.

[0426] 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 specific order presented.

[0427] Each aspect / embodiment described in the present disclosure may be related to 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 a decimal)), 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 The present invention may be applied to systems that use 802.20, Ultra-Wide Band (UWB), Bluetooth (registered trademark), or other appropriate wireless communication methods, or to next-generation systems that are based on and extend these systems. Furthermore, the present invention may be applied to a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0428] 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."

[0429] 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.

[0430] 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.

[0431] 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.

[0432] Also, "decision" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "decision" may be considered to be "deciding" on some action.

[0433] Furthermore, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," or the like.

[0434] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0435] 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."

[0436] 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.

[0437] 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."

[0438] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0439] 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.

[0440] 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.

Claims

1. a transmitter for transmitting capability information indicating support for indicating a transmission configuration indication (TCI) state applicable to multiple types of channels by downlink control information (DCI) without downlink (DL) assignment; a receiving unit that receives information indicating a plurality of TCI states applicable to the plurality of types of channels and the DCI without DL assignment that indicates one or more TCI states among the plurality of TCI states; A terminal having a control unit that determines a reference signal for beam failure detection (BFD) based on one or more TCI states indicated by the DCI without DL assignment when the reference signal is not set by a Radio Resource Control (RRC) information element.

2. The terminal according to claim 1 , wherein the control unit uses, as the reference signal, a TCI state corresponding to a first TCI state ID in the information indicating the plurality of TCI states.

3. transmitting capability information indicating support for indication of transmission configuration indication (TCI) states applicable to multiple types of channels by downlink control information (DCI) without downlink (DL) assignment; receiving information indicating a plurality of TCI states applicable to the plurality of types of channels and the DCI without DL assignment indicating one or more TCI states among the plurality of TCI states; A wireless communication method for a terminal, comprising: when a reference signal for beam failure detection (BFD) is not set by a Radio Resource Control (RRC) information element, determining the reference signal based on the one or more TCI states indicated by the DCI without DL assignment.

4. a receiver for receiving capability information indicating support for indicating a transmission configuration indication (TCI) state applicable to a plurality of types of channels by a downlink control information (DCI) without a downlink (DL) assignment; a transmitter configured to transmit information indicating a plurality of TCI states applicable to the plurality of types of channels and the DCI without DL assignment, the DCI indicating one or more TCI states among the plurality of TCI states; A base station having a control unit that, when a reference signal for beam failure detection (BFD) is not set by a Radio Resource Control (RRC) information element, indicates the reference signal using one or more TCI states indicated by the DCI without DL assignment.

5. A system having a terminal and a base station, The terminal includes a transmitter that transmits capability information indicating support for indicating a transmission configuration indication (TCI) state applicable to a plurality of types of channels by downlink control information (DCI) without downlink (DL) assignment; a receiving unit that receives information indicating a plurality of TCI states applicable to the plurality of types of channels and the DCI without DL assignment that indicates one or more TCI states among the plurality of TCI states; a control unit that determines a reference signal for beam failure detection (BFD) based on the one or more TCI states indicated by the DCI without DL assignment when the reference signal for BFD is not configured by a Radio Resource Control (RRC) information element; The base station includes a receiving unit for receiving the capability information; a transmitter that transmits information indicating the plurality of TCI states and the DCI without DL assignment; A system comprising: a control unit that indicates the reference signal using the one or more TCI states indicated by the DCI without DL assignment.

Images