Terminal, wireless communication method, base station, and system

Abstract

A terminal according to one aspect of the present disclosure comprises: a reception unit that receives a setting indicating one or two beam failure detection reference signal (BFD-RS) sets with regards to a cell; and a control unit that evaluates wireless link quality by using the one or two BFD-RS sets and at least one of two transmission configuration indication (TCI) states associated with one control resource set or two physical downlink control channels (PDCCH). According to one aspect of the present disclosure, beam failure detection can be appropriately implemented.

Description

Technical Field

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

Background Art

[0002] In a Universal Mobile Telecommunications System (UMTS) network, Long Term Evolution (LTE) was standardized for the purpose of further high-speed data rates, low latency, etc. (Non-Patent Document 1). Also, for the purpose of further large capacity and sophistication of LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9), LTE-Advanced (3GPP Rel. 10-14) was standardized.

[0003] A successor system to LTE (for example, also referred to as 5th generation mobile communication system (5G), 5G+(plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 and later, etc.) is also being considered.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a future wireless communication system (e.g., NR), it is considered that a terminal (user terminal, User Equipment (UE)) performs a procedure of detecting a beam failure and switching to another beam (which may be called a beam failure recovery (BFR) procedure, BFR, link recovery procedures, etc.).

[0006] Furthermore, it is also assumed that the terminal communicates using a plurality of transmission / reception points (TRP) / UE panels. In this case, it is conceivable to perform beam failure detection in a plurality of TRPs / plural UE panels, but the problem is how to control beam failure detection (BFD) or beam failure recovery (BFR) in each TRP / UE panel. If the beam failure detection or beam failure recovery in each TRP / UE panel cannot be appropriately controlled, there is a risk of a decrease in communication throughput / communication quality.

[0007] Therefore, one object of the present disclosure is to provide a terminal and a wireless communication method that appropriately perform beam failure detection. 、 Base station and the system as one of the purposes.

Means for Solving the Problems

[0008] A terminal according to an aspect of the present disclosure includes a receiving unit that receives a setting indicating one set of beam failure detection reference signals (BFD-RS), and demodulation reference signals (DM-RS) of one control resource set (CORESET) in which two BFD-RS included in the BFD-RS set are associated with two transmission configuration indication (TCI) states, and a control unit that determines that they are quasi-collocation (QCL). and the control unit evaluates one radio link quality for the CORESET based on the two TCI states .

Advantages of the Invention

[0009] According to one aspect of the present disclosure, beam obstruction detection can be appropriately performed.

Brief Description of the Drawings

[0010]

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Mode for Carrying Out the Invention

[0011] (TCI, Spatial Relationship, QCL) In NR, based on the Transmission Configuration Indication state (TCI state), it is considered to control at least one of the reception processing (e.g., at least one of reception, demapping, demodulation, decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, encoding) of at least one of a signal and a channel (expressed as a signal / channel) in a UE.

[0012] The TCI state may represent what is applied to a downlink signal / channel. What corresponds to the TCI state applied to an uplink signal / channel may be expressed as a spatial relation.

[0013] The TCI state is information regarding the Quasi-Co-Location (QCL) of a signal / channel, and may be called a spatial reception parameter, Spatial Relation Information, etc. The TCI state may be set for each channel or each signal in a UE.

[0014] QCL is an index indicating the statistical properties of a signal / channel. For example, when a certain signal / channel and another signal / channel are in a QCL relationship, it may mean that at least one of Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same (QCL with respect to at least one of these) among these different multiple signals / channels.

[0015] Note that the spatial reception parameter may correspond to the reception beam (e.g., reception analog beam) of the UE, and the beam may be specified based on spatial QCL. The QCL (or at least one element of QCL) in the present disclosure may be read as sQCL (spatial QCL).

[0016] Multiple types (QCL types) of QCL may be defined. For example, four QCL types A - D with different parameters (or parameter sets) that can be assumed to be the same may be provided, and the parameters (which may also be referred to as QCL parameters) are shown below: · QCL type A (QCL - A): Doppler shift, Doppler spread, average delay, and delay spread, · QCL type B (QCL - B): Doppler shift and Doppler spread, · QCL type C (QCL - C): Doppler shift and average delay, · QCL type D (QCL - D): Spatial reception parameter.

[0017] The assumption by the UE that a certain control resource set (Control Resource Set (CORESET)), channel, or reference signal is in a relationship with a specific QCL (e.g., QCL type D) with another CORESET, channel, or reference signal may be referred to as a QCL assumption.

[0018] The UE may determine at least one of the transmission beam (Tx beam) and the reception beam (Rx beam) of the signal / channel based on the TCI state or QCL assumption of the signal / channel.

[0019] The TCI state may be, for example, information regarding the QCL between the target channel (in other words, the reference signal (Reference Signal (RS)) for the channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by upper 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 the spatial relation is set (specified) may be at least one of, for example, a Physical Downlink Shared Channel (PDSCH), a Physical Downlink Control Channel (PDCCH), a Physical Uplink Shared Channel (PUSCH), and a Physical Uplink Control Channel (PUCCH).

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

[0023] The SSB is a signal block including at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). The SSB may be called an SS / PBCH block.

[0024] The RS of QCL type X in the TCI state may mean the RS related to a certain channel / signal (DMRS) and QCL type X, and this RS may also be called the QCL source of QCL type X in the TCI state.

[0025] (Multi-TRP) In NR, it is being considered that one or more transmission / reception points (TRPs) (multi-TRP (MTRP)) use one or more panels to perform DL transmission to the UE. Also, it is being considered that the UE uses one or more panels to perform UL transmission to one or more TRPs.

[0026] Note that multiple TRPs may correspond to the same cell identifier (cell ID) or different cell IDs. The cell ID may be a physical cell ID or a virtual cell ID.

[0027] Multi-TRP (e.g., TRP#1, #2) is connected by an ideal / non-ideal backhaul, and information, data, etc. may be exchanged. Different codewords (CWs) and different layers may be transmitted from each TRP of the multi-TRP. As a form of multi-TRP transmission, Non-Coherent Joint Transmission (NCJT) may be used.

[0028] In NCJT, for example, TRP#1 modulates and maps the first codeword, layer-maps it to the first number of layers (e.g., 2 layers), and uses the first precoding to transmit the first PDSCH. Also, TRP#2 modulates and maps the second codeword, layer-maps it to the second number of layers (e.g., 2 layers), and uses the second precoding to transmit the second PDSCH.

[0029] In addition, multiple PDSCHs (multi-PDSCH) to be NCJT may be defined to partially or completely overlap with respect to at least one of the time and frequency domains. That is, the first PDSCH from the first TRP and the second PDSCH from the second TRP may overlap with respect to at least one of the time and frequency resources.

[0030] These first PDSCH and second PDSCH may be assumed to be not quasi-co-located. The reception of the multi-PDSCH may be interpreted as the simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

[0031] Multiple PDSCHs (which may be referred to as multi-PDSCH (multiple PDSCH)) from multiple TRPs may be scheduled using one DCI (single DCI, single PDCCH) (single master mode, single-DCI based multi-TRP). Multiple PDSCHs from multiple TRPs may be scheduled respectively using multiple DCIs (multi-DCI, multiple PDCCH) (multi-master mode, multi-DCI based multi-TRP).

[0032] In Ultra-Reliable and Low Latency Communications (URLLC) for multi-TRP, it is being considered to support repetition of Physical Downlink Shared Channel (PDSCH) (transport block (TB) or codeword (CW)) across multiple TRPs. Repetition schemes (URLLC scheme, reliability enhancement scheme, e.g., scheme 1a, 2a, 2b, 3, 4) across multiple TRPs in the frequency domain or layer (spatial) domain or time domain are being considered. In scheme 1a, multi-PDSCH from multiple TRPs is space division multiplexing (SDM). In schemes 2a and 2b, PDSCH from multiple TRPs is frequency division multiplexing (FDM). In scheme 2a, the redundancy version (RV) for multiple TRPs is the same. In scheme 2b, the RV for multiple TRPs may be the same or different. In schemes 3 and 4, multi-PDSCH from multiple TRPs is time division multiplexing (TDM). In scheme 3, multi-PDSCH from multiple TRPs is transmitted within one slot. In scheme 4, multi-PDSCH from multiple TRPs is transmitted in different slots.

[0033] According to such a multi-TRP scenario, more flexible transmission control using a good-quality channel is possible.

[0034] In order to support multi-TRP transmission within a cell (intra-cell, having the same cell ID) and between cells (inter-cell, having different cell IDs) based on multiple PDCCHs, in the RRC configuration information for linking multiple pairs of PDCCH and PDSCH having multiple TRPs, one control resource set (CORESET) within the PDCCH configuration information (PDCCH-Config) may correspond to one TRP.

[0035] If at least one of the following Conditions 1 and 2 is satisfied, the UE may determine that it is multi-TRP based on multi-DCI. In this case, the TRP may be re-mapped to the CORESET pool index. [Condition 1] One CORESET pool index is configured. [Condition 2] Two different values (e.g., 0 and 1) of the CORESET pool index are configured.

[0036] If the following condition is satisfied, the UE may determine that it is multi-TRP based on single-DCI. In this case, the two TRPs may be re-mapped to two TCI states indicated by MAC CE / DCI. [Condition] "Enhanced TCI States Activation / Deactivation for UE-specific PDSCH MAC CE" is used to indicate one or two TCI states for one code point of the TCI field in DCI.

[0037] The common beam indication DCI 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 a UE-group common DCI format.

[0038] (Multi-TRP PDCCH) For the reliability of multi-TRP PDCCH based on non-single frequency network (SFN), the following Considerations 1 to 3 are being considered. [Consideration 1] Channel coding / rate matching is based on one repetition, and the same coded bits are repeated in other repetitions. [Consideration 2] Each repetition has the same number of control channel elements (CCEs), the same coded bits, and corresponds to the same DCI payload. [Consideration 3] Two or more PDCCH candidates are explicitly linked to each other. The UE knows that link before decoding.

[0039] The following Options 1-2, 1-3, 2, 3 for PDCCH repetition are being considered.

[0040] [Option 1-2] Two sets of PDCCH candidates are respectively associated with two TCI states of a CORESET. Here, the same CORESET, the same search space (SS) set, and PDCCH repetition in different monitoring occasions are used.

[0041] [Option 1-3] Two sets of PDCCH candidates are respectively associated with two SS sets. Both SS sets are associated with a CORESET, and each SS set is associated with only one TCI state of its CORESET. Here, the same CORESET and two SS sets are used.

[0042] [Option 2] One SS set is associated with two different CORESETs.

[0043] [Option 3] Two SS sets are respectively associated with two CORESETs.

[0044] Thus, it is being considered that two PDCCH candidates within two SS sets for PDCCH repetition are supported and the two SS sets are explicitly linked.

[0045] (SFN / HST) In LTE, it is difficult to arrange in a tunnel of an HST (high speed train). A large antenna performs transmission outside / inside the tunnel. For example, the transmission power of the large antenna is about 1 to 5 W. For handover, it is important that the UE transmits outside the tunnel before entering the tunnel. For example, the transmission power of a small antenna is about 250 mW. A plurality of small antennas (transmitting / receiving points) having the same cell ID and a distance of 300 m form a single frequency network (SFN). All small antennas within the SFN transmit the same signal at the same time on the same PRB. It is assumed that the terminal transmits and receives to / from one base station. Actually, a plurality of transmitting / receiving points transmit the same DL signal. When moving at high speed, transmitting / receiving points in units of several kilometers form one cell. Handover is performed when crossing cells. Thereby, the handover frequency can be reduced.

[0046] In NR, in order to communicate with a terminal (hereinafter also referred to as UE) included in a moving body (HST (high speed train)) such as a train moving at high speed, it is assumed to use a beam transmitted from a transmission point (for example, RRH). In an existing system (for example, Rel. 15), it is supported to transmit a unidirectional beam from the RRH to communicate with the moving body (see FIG. 1A).

[0047] In FIG. 1A, a case is shown where RRHs are installed along the moving path (or moving direction, traveling direction, running path) of the moving body, and beams are formed from each RRH toward the traveling direction side of the moving body. The RRH that forms a unidirectional beam may be called a uni-directional RRH. In the example shown in FIG. 1A, the moving body has a minus Doppler shift (-f from each RRHD ) receives.

[0048] Here, the case where a beam is formed on the traveling direction side of the moving body is shown, but it is not limited to this, and the beam may be formed on the side opposite to the traveling direction, or the beam may be formed in any direction regardless of the traveling direction of the moving body.

[0049] After Rel.16, it is also assumed that a plurality (for example, two or more) of beams are transmitted from the RRH. For example, it is assumed that beams are formed for both the traveling direction of the moving body and the opposite direction thereof (see FIG. 1B).

[0050] In FIG. 1B, the case where RRHs are installed along the moving path of the moving body and beams are formed from each RRH to both the traveling direction side and the opposite side of the traveling direction of the moving body is shown. The RRH that forms beams in a plurality of directions (for example, two directions) may be called a bi - directional RRH.

[0051] In this HST, the UE communicates in the same manner as a single TRP. In the base station implementation, it can be transmitted from a plurality of TRPs (with the same cell ID).

[0052] In the example of FIG. 1B, when two RRHs (here, RRH#1 and RRH#2) use SFN, when the moving body is in the middle of the two RRHs, the signal that receives a minus Doppler shift switches to a signal that receives a plus Doppler shift with higher power. In this case, the change range of the maximum Doppler shift that requires correction is from -f D to +f D and becomes twice that of the case of the unidirectional RRH.

[0053] In the present disclosure, a positive Doppler shift may be read as information regarding a positive Doppler shift, a positive (forward) Doppler shift, or positive (forward) Doppler information. Also, a negative Doppler shift may be read as information regarding a negative Doppler shift, a negative (backward) Doppler shift, or negative (backward) Doppler information.

[0054] Here, as HST schemes, the following Schemes 0 to 2 (HST Schemes 0 to 2) are compared.

[0055] In Scheme 0 of FIG. 2A, a tracking reference signal (TRS), a DMRS, and a PDSCH are transmitted commonly (using the same time and frequency resources) to two TRPs (RRHs) (normal SFN, transparent SFN, HST-SFN).

[0056] In Scheme 0, since the UE receives a DL channel / signal equivalent to a single TRP, the TCI state of the PDSCH is one.

[0057] In Rel. 16, an RRC parameter for distinguishing between transmission using a single TRP and transmission using an SFN is defined. When the UE reports corresponding UE capability information, the UE may distinguish between reception of a DL channel / signal of a single TRP and reception of a PDSCH assuming an SFN based on the RRC parameter. On the other hand, the UE may perform transmission / reception using an SFN assuming a single TRP.

[0058] In Scheme 1 of FIG. 2B, the TRS is transmitted specifically for each TRP (using different time / frequency resources for each TRP). In this example, TRS1 is transmitted from TRP#1 and TRS2 is transmitted from TRP#2.

[0059] In Scheme 1, since the UE receives DL channels / signals from each TRP using the TRS from each TRP, the number of TCI states for PDSCH is two.

[0060] In Scheme 2 of FIG. 2C, the TRS and DMRS are transmitted uniquely for each TRP. In this example, TRS1 and DMRS1 are transmitted from TRP#1, and TRS2 and DMRS2 are transmitted from TRP#2. Compared with Scheme 0, Schemes 1 and 2 can suppress rapid changes in Doppler shift and appropriately estimate / compensate for Doppler shift. Since the DMRS of Scheme 2 increases compared to the DMRS of Scheme 1, the maximum throughput of Scheme 2 is lower than that of Scheme 1.

[0061] In Scheme 0, the UE switches between a single TRP and SFN based on upper layer signaling (RRC information element / MAC CE).

[0062] The UE may switch between Scheme 1 / Scheme 2 / NW pre - compensation scheme based on upper layer signaling (RRC information element / MAC CE).

[0063] In Scheme 1, two TRS resources are respectively set for the forward and reverse directions of the HST.

[0064] In the example of FIG. 3A, the TRPs (TRP#0, #2, …) that transmit DL signals in the reverse direction of the HST transmit the first TRS (TRS arriving from before the HST) in the same time and frequency resources (SFN). The TRPs (TRP#1, #3, …) that transmit DL signals in the forward direction of the HST transmit the second TRS (TRS arriving from after the HST) in the same time and frequency resources (SFN). The first TRS and the second TRS may be transmitted / received using different frequency resources.

[0065] In the example of FIG. 3B, TRS1-1 to 1-4 are transmitted as the first TRS, and TRS2-1 to 2-4 are transmitted as the second TRS.

[0066] Considering beam operation, the first TRS is transmitted using 64 beams and 64 time resources, and the second TRS is transmitted using 64 beams and 64 time resources. The beams of the first TRS and the beams of the second TRS are considered to be equal (the QCL type D RS is equal). By multiplexing the first TRS and the second TRS on the same time resources and different frequency resources, the resource utilization efficiency can be improved.

[0067] In the example of FIG. 4A, RRH#0-#7 are arranged along the movement path of the HST. RRH#0-#3 and RRH#4-#7 are respectively connected to baseband units (BBU)#0 and #1. Each RRH is a bidirectional RRH, and forms a beam using each transmission / reception point (TRP) in both the forward direction and the reverse direction of the movement path.

[0068] In the received signal of the example of FIG. 4B (single TRP (SFN) / scheme 1), when the UE receives a signal / channel transmitted from TRP#2n-1 (n is an integer greater than or equal to 0) (beam in the forward direction of the HST, beam from behind the UE), a negative Doppler shift (in this example, -fD) occurs. Also, when the UE receives a signal / channel transmitted from TRP#2n (n is an integer greater than or equal to 0) (beam in the reverse direction of the forward direction of the HST, beam from in front of the UE), a positive Doppler shift (in this example, +fD) occurs.

[0069] Since Release 17, it has been considered that the base station performs a Doppler pre-compensation scheme (Pre-Doppler Compensation scheme, Doppler pre-Compensation scheme, network (NW) pre-compensation scheme, HST NW pre-compensation scheme) when transmitting downlink (DL) signals / channels to the UE in the HST from the TRP. When the TRP transmits DL signals / channels to the UE, it is possible to reduce the influence of the Doppler shift when the UE receives the DL signals / channels by performing Doppler compensation in advance. In the present disclosure, the Doppler pre-compensation scheme may be a combination of Scheme 1 and the pre-compensation of the Doppler shift by the base station.

[0070] In the Doppler pre-compensation scheme, it is considered that the TRS from each TRP is transmitted without Doppler pre-compensation, and the PDSCH from each TRP is transmitted with Doppler pre-compensation.

[0071] In the Doppler pre-compensation scheme, the TRP that forms a beam on the advancing direction side of the moving path and the TRP that forms a beam on the side opposite to the advancing direction of the moving path perform Doppler correction and then transmit DL signals / channels to the UE within the HST. In this example, TRP#2n - 1 performs positive Doppler correction, and TRP#2n performs negative Doppler correction to reduce the influence of the Doppler shift when the UE receives the signal / channel (Fig. 4C).

[0072] Note that in the situation of Fig. 4C, since the UE receives the DL channel / signal from each TRP using the TRS from each TRP, the TCI state of the PDSCH may be two.

[0073] Furthermore, starting from Rel.17, it is being considered to dynamically switch between single TRP and SFN using the TCI field (TCI state field). For example, using the RRC information element / MAC CE (e.g., Enhanced TCI States Activation / Deactivation for UE-specific PDSCH MAC CE) / DCI (TCI field), one or two TCI states are set / indicated at each TCI code point (the code point of the TCI field, DCI code point). When the UE is set / indicated with one TCI state, it may determine that it is receiving the PDSCH of a single TRP. Also, when the UE is set / indicated with two TCI states, it may determine that it is receiving the PDSCH of an SFN using multi-TRP.

[0074] (SFN PDCCH repetition) In Rel.15, one TCI state without a CORESET pool index (which may be called TRP Info) is set for one CORESET.

[0075] Regarding the enhancements of PDCCH / CORESET defined in Rel.16, for multi-TRP based on multi-DCI, a CORESET pool index is set for each CORESET.

[0076] Starting from Rel.17, the following enhancements 1 and 2 regarding PDCCH / CORESET are being considered.

[0077] In the case where a plurality of antennas (small antennas, transmission / reception points) having the same cell ID form a single frequency network (SFN), for one CORESET, up to two TCI states can be set / activated by upper layer signaling (RRC signaling / MAC CE) (Enhancement 1). The SFN contributes to at least one of the operation and reliability improvement of high speed trains (HST).

[0078] Also, in the repeated transmission of PDCCH (which may simply be called "repetition"), two PDCCH candidates in two search space sets are linked, and each search space set is associated with the corresponding CORESET (Enhancement 2). The two search space sets may be associated with the same or different CORESETs. For one CORESET, one (up to one) TCI state can be set / activated by upper layer signaling (RRC signaling / MAC CE).

[0079] If two search space sets are associated with different CORESETs having different TCI states, it may mean repeated transmission of multi-TRP. If two search space sets are associated with the same CORESET (CORESET with the same TCI state), it may mean repeated transmission of single-TRP.

[0080] (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., gNB (gNodeB)) may use a beam used for signal transmission (also referred to as a transmission beam, Tx beam, etc.) and a beam used for signal reception (also referred to as a reception beam, Rx beam, etc.).

[0081] When beamforming is used, it is assumed that the wireless link quality deteriorates because it is more susceptible to interference by obstacles. Frequent occurrence of radio link failure (RLF) may occur due to the deterioration of the wireless link quality. When RLF occurs, reconnection of the cell is required, so frequent occurrence of RLF leads to deterioration of the system throughput.

[0082] 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 be called beam recovery (BR), beam failure recovery (BFR), L1 / L2 (Layer 1 / Layer 2) beam recovery, etc.) is performed. Note that the BFR procedure may simply be called BFR.

[0083] Note that beam failure (BF) in the present disclosure may be called link failure.

[0084] FIG. 5 is a diagram showing an example of a beam recovery procedure in Rel. 15 NR. The number of beams and the like are examples and are not limited thereto. In the initial state (step S101), the UE performs measurements based on reference signal (RS) resources transmitted using two beams.

[0085] The RS may be at least one of a synchronization signal block (SSB) and a channel state information RS (CSI-RS). Note that the SSB may be called an SS / PBCH (Physical Broadcast Channel) block or the like.

[0086] 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 the SSB, the SSB, a CSI-RS, a Demodulation Reference Signal (DMRS), a beam-specific signal, etc., or a signal configured by extending, modifying, etc. these. The RS measured in step S101 may be called a RS for beam failure detection (Beam Failure Detection RS (BFD-RS), RS for beam failure detection), or a RS for use in a beam recovery procedure (BFR-RS), etc.

[0087] In step S102, due to the radio wave from the base station being interfered with, the UE cannot detect the BFD-RS (or the reception quality of the RS deteriorates). Such interference may occur due to, for example, obstacles between the UE and the base station, fading, interference, etc.

[0088] When a predetermined condition is satisfied, the UE detects a beam failure. For example, the UE may detect the occurrence of a beam failure when the BLER (Block Error Rate) is less than a threshold for all of the set BFD-RS (BFD-RS resource setting). 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).

[0089] Note that the criteria for judgment are not limited to BLER, and may also be the 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 such as the Physical Downlink Control Channel (PDCCH). BFD-RS may be expected to be in Quasi-Co-Location (QCL) with the DMRS of the PDCCH monitored by the UE.

[0090] Here, QCL is an indicator showing the statistical properties of a channel. For example, when a certain signal / channel and another signal / channel are in a QCL relationship, it may be meant that at least one of the doppler shift, doppler spread, average delay, delay spread, and spatial parameter (for example, spatial Rx parameter) is the same (QCL with respect to at least one of these) among these different multiple signals / channels.

[0091] Note that the spatial reception parameter may correspond to the reception beam of the UE (for example, the reception analog beam), and the beam may be identified based on spatial QCL. The QCL (or at least one element of QCL) in the present disclosure may be read as sQCL (spatial QCL).

[0092] Information regarding BFD-RS (for example, the index, resource, number, number of ports, precoding, etc. of the RS), information regarding beam failure detection (BFD) (for example, the above-mentioned threshold), etc. may be set (notified) to the UE using upper layer signaling or the like. The information regarding BFD-RS may also be called information regarding BFR resources, etc.

[0093] When the upper layer of the UE (e.g., the MAC layer) receives a beam failure instance notification from the UE's PHY layer, it may start a predetermined timer (which may be called a beam failure detection timer). If the UE's MAC layer receives the beam failure instance notification a certain number of times (e.g., beamFailureInstanceMaxCount set by RRC) or more before the timer expires, it may trigger a BFR (e.g., start one of the random access procedures described below).

[0094] When there is no notification from the UE or when 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.

[0095] In step S103, the UE starts a search for a new candidate beam (candidate beam detection (CBD)) for new communication for beam recovery. The UE may select a new candidate beam corresponding to the RS by measuring a predetermined RS. The RS measured in step S103 may be called a new candidate RS, an RS for new candidate beam identification, an NCBI-RS (New Candidate Beam Identification RS), an RS for new beam identification, an RS for new beam identification, an NBI-RS (New Beam Identification RS), a CBI-RS (Candidate Beam Identification RS), a CB-RS (Candidate Beam RS), a candidate beam detection RS (Candidate Beam Detection RS, CBD-RS), etc. The NBI-RS may be the same as or different from the BFD-RS. Note that the new candidate beam may also be simply called a candidate beam or a candidate RS.

[0096] The UE may determine, as a new candidate beam, a beam corresponding to an RS that satisfies a predetermined condition. For example, the UE may determine a new candidate beam based on an RS among the configured NBI-RSs whose L1-RSRP exceeds a threshold. Note that the criteria for determination are not limited to L1-RSRP. The L1-RSRP related to the SSB may be referred to as SS-RSRP. The L1-RSRP related to the CSI-RS may be referred to as CSI-RSRP.

[0097] Information related to NBI-RS (such as RS resources, number, number of ports, precoding, etc.), information related to new beam identification (NBI) (such as the above-mentioned threshold), etc. may be set (notified) to the UE using upper layer signaling, etc. Information related to the new candidate RS (or NBI-RS) may be obtained based on information related to BFD-RS. Information related to NBI-RS may also be referred to as information related to NBI resources, etc.

[0098] Note that BFD-RS, NBI-RS, etc. may be mutually read as Radio Link Monitoring RS (RLM-RS).

[0099] In step S104, the UE that has identified a new candidate beam transmits a Beam Failure Recovery reQuest (BFRQ). The beam recovery request may also be referred to as a beam recovery request signal, a beam failure recovery request signal, etc.

[0100] The BFRQ may be transmitted using, for example, at least one of a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH), a Physical Uplink Shared Channel (PUSCH), and a configured grant (CG) PUSCH.

[0101] The BFRQ may include information on the newly identified candidate beam / new candidate RS identified in step S103. Resources for the BFRQ may be associated with the newly identified candidate beam. Information on the beam may be notified using a beam index (Beam Index (BI)), a port index of a predetermined reference signal, an RS index, a resource index (e.g., a CSI-RS resource indicator (CSI-RS Resource Indicator (CRI)), an SSB resource indicator (SSBRI)), etc.

[0102] In Rel.15 NR, contention-based BFR (CB-BFR) based on a contention-based random access (RA) procedure and contention-free BFR (CF-BFR) based on a contention-free random access procedure are being considered. In CB-BFR and CF-BFR, the UE may transmit a preamble (also referred to as an RA preamble, a physical random access channel (PRACH), an RACH preamble, etc.) as the BFRQ using PRACH resources.

[0103] In CB-BFR, the UE may transmit a preamble randomly selected from one or more preambles. On the other hand, in CF-BFR, the UE may transmit a preamble assigned uniquely to the UE from the base station. In CB-BFR, the base station may assign the same preamble to multiple UEs. In CF-BFR, the base station may assign preambles individually to UEs.

[0104] Note that CB-BFR and CF-BFR may also be referred to as CB PRACH-based BFR (contention-based PRACH-based BFR (CBRA-BFR)) and CF PRACH-based BFR (contention-free PRACH-based BFR (CFRA-BFR)), respectively. CBRA-BFR may also be referred to as CBRA for BFR. CFRA-BFR may also be referred to as CFRA for BFR.

[0105] Regardless of whether it is CB-BFR or CF-BFR, information regarding the PRACH resource (RA preamble) may be notified, for example, by upper layer signaling (such as RRC signaling). For example, the information may include information indicating the correspondence between the detected DL-RS (beam) and the PRACH resource, and different PRACH resources may be associated with each DL-RS.

[0106] In step S105, the base station that has detected the BFRQ transmits a response signal (which may also be referred to as a gNB response, etc.) to the BFRQ from the UE. The response signal may include reconfiguration information (for example, configuration information of the DL-RS resource) for one or more beams.

[0107] The response signal may be transmitted, for example, in the UE common search space of the PDCCH. The response signal may be notified using a PDCCH (DCI) scrambled by a cyclic redundancy check (CRC) with a UE identifier (for example, a Cell-Radio RNTI (C-RNTI)). The UE may determine at least one of the transmission beam and the reception beam to be used based on the beam reconfiguration information.

[0108] 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.

[0109] Regarding CB-BFR, when the UE receives a PDCCH corresponding to its own C-RNTI, it may be determined that contention resolution has succeeded.

[0110] Regarding the process of step S105, a period may be set for the UE to monitor the response from the base station (e.g., gNB) to the BFRQ. This period may be referred to as, for example, the gNB response window, the gNB window, the beam recovery request response window, etc. If the UE does not detect a gNB response within the window period, it may retransmit the BFRQ.

[0111] In step S106, the UE may send a message indicating that the beam reconfiguration to the base station has been completed. This message may be sent, for example, by PUCCH or by PUSCH.

[0112] Beam recovery success (BR success) may represent, for example, the case of reaching step S106. On the other hand, beam recovery failure (BR failure) may correspond to, for example, the BFRQ transmission reaching a predetermined number of times or the expiration of the Beam-failure-recovery-Timer.

[0113] In Rel.15, it is supported to perform the beam recovery procedure (e.g., notification of BFRQ) for the beam failure detected in the SpCell (PCell / PSCell) using the random access procedure. On the other hand, in Rel.16, it is supported to perform the beam recovery procedure (e.g., notification of BFRQ) for the beam failure detected in the SCell using at least one of the PUCCH for BFR (e.g., scheduling request (SR)) transmission and the MAC CE for BFR (e.g., UL-SCH) transmission.

[0114] For example, the UE may transmit information regarding beam failure by using MAC CE-based two steps. The information regarding beam failure may include information regarding the cell in which the beam failure is detected and information regarding a new candidate beam (or a new candidate RS index).

[0115] [Step 1] When BF is detected, a PUCCH-BFR (scheduling request (SR)) may be transmitted from the UE to the PCell / PSCell. Then, a UL grant (DCI) for the following Step 2 may be transmitted from the PCell / PSCell to the UE. If there is a MAC CE (or UL-SCH) for transmitting information regarding a new candidate beam when a beam failure is detected, Step 1 (for example, PUCCH transmission) may be omitted and Step 2 (for example, MAC CE transmission) may be performed.

[0116] [Step 2] Then, the UE may transmit information regarding the cell (for example, cell index) in which the beam failure is detected (failed) and information regarding a new candidate beam to the base station (PCell / PSCell) via an uplink channel (for example, PUSCH) by using a MAC CE. After that, after receiving a response signal from the base station through the BFR procedure, the QCL of PDCCH / PUCCH / PDSCH / PUSCH may be updated to a new beam after a predetermined period (for example, 28 symbols).

[0117] Note that the numbers of these steps are only for the purpose of explanation, and a plurality of steps may be combined or the order may be changed. Also, whether to perform BFR may be set for the UE by using upper layer signaling.

[0118] (BFD-RS / NBI-RS) In BFD, the UE may configure explicit BFD-RS (e.g., SSB / CSI-RS) through upper layer signaling or the like. Alternatively, in BFD, the UE may configure implicit BFD-RS based on the TCI state of PDCCH / CORESET (the UE may determine BFD-RS based on the TCI state). Also, in BFR, the UE may configure explicit NBI-RS (e.g., SSB / CSI-RS) through upper layer signaling or the like. Hereinafter, explicit BFD-RS, implicit BFD-RS, explicit NBI-RS, etc. will be specifically described.

[0119] In Rel.16, for each BWP of one serving cell, for radio link quality measurement on that BWP of that serving cell, the UE is provided with a set q of periodic (P)-CSI-RS resource configuration indexes by the failureDetectionResourcesToAddModList 0 bars. For each BWP of one serving cell, for radio link quality measurement on that BWP of that serving cell, the UE is provided with at least one set q of P-CSI-RS resource configuration indexes and SS / PBCH block indexes by the candidateBeamRSList or candidateBeamRSListExt or candidateBeamRSSCellList 1 bars.

[0120] q 0 The bar is a notation with an overline on "q 0 ". Hereinafter, q 0 The bar is simply denoted as q 0 . q 1 The bar is a notation with an overline on "q 1 ". Hereinafter, q 1 The bar is simply denoted as q 1 .

[0121] The set q of P-CSI-RS resources provided by the failure detection resource 0 may be referred to as explicit BFD-RS. Set q 1 may be referred to as explicit New Beam Identification (NBI)-RS.

[0122] In other words, the UE can be explicitly configured with the set q of BFD-RS for per-cell BFR 0 The UE can perform L1-RSRP measurements and the like using the RS resources corresponding to the indexes included in at least one of set q

[0123] and set q 0 and set q 1 to detect beam failures.

[0124] Note that in the present disclosure, providing the above-mentioned upper layer parameter indicating the index information corresponding to the BFD resource may be mutually interpreted as setting the BFD resource, setting the BFD-RS, etc. In the present disclosure, the set q of the BFD resource, the periodic CSI-RS resource setting index or the SSB index 0 the BFD-RS may be mutually interpreted.

[0125] If the UE is not provided with q 0 by the failure detection resources for one BWP of its serving cell, the UE determines to include in set q the P-CSI-RS resource setting index having the same value as the RS index in the RS set indicated by the TCI-State for the corresponding CORESET used for PDCCH monitoring. If there are two RS indexes in one TCI state, set q 0 includes the RS index having the QCL type D setting for the corresponding TCI state. The UE uses that set q 0 0 ​It is assumed to include up to two RS indexes. The UE assumes single-port RS within its set q 0 In it.

[0126] This set q 0 May be called implicit BFD-RS.

[0127] The physical layer in the UE follows the set q of resource settings 0 To evaluate the radio link quality against the threshold Q out,LR For the set q 0 The UE evaluates the radio link quality only according to the SS / PBCH block on the PCell or PSCell quasi co-located with the DM-RS of the PDCCH reception monitored by the UE, or the P-CSI-RS resource setting quasi co-located with the DM-RS of the PDCCH reception monitored by the UE.

[0128] In other words, for the set q 0 The UE evaluates the radio link quality according to the BFD-RS QCLed with the DMRS of the PDCCH / CORESET.

[0129] (Per-cell BFR and per-TRP BFR) Since the above-mentioned (Rel.15 / 16) BFR is performed per cell, it may be called per-cell BFR. On the contrary, the BFR performed per TRP is under consideration.

[0130] For single DCI-based multi-TRP, it is considered to set new RRC configuration parameters (for example, TRP-ID, group ID, new ID, etc.). The new RRC configuration parameters may follow either Option 1 or Option 2 below. [Option 1] Each CORESET is associated with a new ID. When two sets of BFD-RS for BFR per TRP are configured by the upper layer, the CORESET that is QCLed with the BFD-RS within one set may be associated with the same new ID, and the CORESET that is QCLed with the BFD-RS in different sets may be associated with different new IDs. [Option 2] Each TCI state is associated with a new ID. When two sets of BFD-RS for BFR per TRP are configured by the upper layer, the TCI state / CORESET that is QCLed with the BFD-RS within one set may be associated with the same new ID, and the TCI state / CORESET that is QCLed with the BFD-RS in different sets may be associated with different new IDs.

[0131] The explicit BFD-RS set configuration considering at least one of two TCI states and a single DCI-based multi-TRP for a CORESET has not been fully considered.

[0132] Regarding the explicit BFD-RS set configuration, the following cases #1 to #5 can be considered. [Case #1] In single-cell / single-TRP operation, when using an SFN CORESET with two TCI states, one BFD-RS set is configured for per-cell BFR. [Case #2] In single DCI-based multi-TRP operation, when all CORESETs are associated with one TCI state, one BFD-RS set is configured for per-cell BFR. [Case #3] In single DCI-based multi-TRP operation, when all CORESETs are associated with one TCI state, up to two BFD-RS sets are configured for per-TRP BFR. [Case #4] In the single DCI-based multi-TRP operation, when using an SFN CORESET with two TCI states, one BFD-RS set is configured for per-cell BFR (per-cell BFR). [Case #5] In the single DCI-based multi-TRP operation, when using an SFN CORESET with two TCI states, up to two BFD-RS sets are configured for per-TRP BFR (per-TRP BFR).

[0133] SFN PDCCH scheme 1 is being considered to include HST and URLLC. In the present disclosure, SFN PDCCH scheme 1, SFN PDCCH scheme, SFN PDCCH, and TRP-based pre-compensation scheme may be read interchangeably with each other.

[0134] Regarding implicit BFD-RS, the SFN PDCCH scheme may include both one and two TCI states. If the SFN PDCCH scheme is configured and two TCI states are activated for at least one CORESET, it is being considered to use the RS of the CORESET with one and two TCI states for the implicit configuration of the RS for BFD.

[0135] The problem is how the calculation is performed using the BFD-RS associated with the SFN PDCCH / CORESET. When two TCI states are activated for one CORESET, the UE is considered to assume SFN transmission for multi-TRP and calculate the hypothetical block error rate (BLER) using the BFD-RS pair of the CORESET.

[0136] The explicit BFD-RS set configuration considering two linked PDCCHs has not been fully considered.

[0137] Regarding the explicit BFD-RS set configuration, the following cases #a to #e are conceivable. [Case #a] For per-cell BFR in the operation of a single cell / single TRP using two linked PDCCHs, one BFD-RS set is configured. [Case #b] For per-cell BFR in the operation of a single DCI-based multi-TRP using two linked PDCCHs, one BFD-RS set is configured. [Case #c] For per-TRP BFR in the operation of a single DCI-based multi-TRP using two linked PDCCHs, up to two BFD-RS sets are configured. [Case #d] For per-cell BFR in the operation of a multi-DCI-based multi-TRP using two linked PDCCHs, one BFD-RS set is configured. [Case #e] For per-TRP BFR in the operation of a multi-DCI-based multi-TRP using two linked PDCCHs, up to two BFD-RS sets are configured.

[0138] Thus, there are cases where the operation regarding the explicit BFD-RS set configuration is not clear (especially cases #1, #4, #5, #a to #e). If such an operation is not clear, there is a risk of deterioration in communication quality / communication throughput.

[0139] Therefore, the inventors conceived of an operation regarding the explicit BFD-RS set configuration.

[0140] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. The wireless communication methods according to the respective embodiments may be applied individually or in combination.

[0141] In the present disclosure, "A / B" and "at least one of A and B" may be read interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C".

[0142] In the present disclosure, activate, deactivate, indicate (or specify), select, configure, update, determine, etc. may be read interchangeably. In the present disclosure, support, control, be controllable, operate, be operable, etc. may be read interchangeably.

[0143] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, upper layer parameters, Information Element (IE), configurations, etc. may be read interchangeably. In the present disclosure, Medium Access Control control element (MAC Control Element (CE)), update commands, activation / deactivation commands, etc. may be read interchangeably.

[0144] In the present disclosure, upper layer signaling may be any one of, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

[0145] In the present disclosure, MAC signaling may use, for example, a MAC control element (MAC CE), a MAC Protocol Data Unit (PDU), etc. 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.

[0146] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), etc.

[0147] In the present disclosure, an index, an identifier (Identifier (ID)), an indicator, a resource ID, etc. may be read interchangeably with each other. In the present disclosure, a sequence, a list, a set, a group, a cluster, a subset, etc. may be read interchangeably with each other.

[0148] In the present disclosure, panel, UE panel, panel group, beam, beam group, precoder, Uplink (UL) transmission entity, Transmission / Reception Point (TRP), base station, Spatial Relation Information (SRI), spatial relation, SRS Resource Indicator (SRI), Control Resource Set (CORESET), Physical Downlink Shared Channel (PDSCH), Codeword (CW), Transport Block (TB), Reference Signal (RS), antenna port (e.g., Demodulation Reference Signal (DMRS) port), antenna port group (e.g., DMRS port group), group (e.g., spatial relation group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) group, PUCCH resource group), resource (e.g., reference signal resource, SRS resource), resource set (e.g., reference signal resource set), CORESET pool, downlink Transmission Configuration Indication state (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, Quasi-Co-Location (QCL), QCL assumption, etc. may be read as each other.

[0149] In the present disclosure, single TRP, single TRP system, single TRP transmission, single PDSCH may be read interchangeably with each other. In the present disclosure, multi-TRP, multi-TRP system, multi-TRP transmission, multi-PDSCH may be read interchangeably with each other. In the present disclosure, single DCI, single PDCCH, multi-TRP based on single DCI, activation of two TCI states on at least one TCI code point may be read interchangeably with each other.

[0150] In the present disclosure, single TRP, a channel using single TRP, a channel using one TCI state / space relation, non-activation of multi-TRP by RRC / DCI, non-activation of multiple TCI states / space relations by RRC / DCI, not setting one CORESET pool index (CORESETPoolIndex) value for any CORESET, and no code point of the TCI field being mapped to two TCI states may be read interchangeably with each other.

[0151] In the present disclosure, multi-TRP, a channel using multi-TRP, a channel using multiple TCI states / space relations, activation of multi-TRP by RRC / DCI, activation of multiple TCI states / space relations by RRC / DCI, at least one of multi-TRP based on single DCI and multi-TRP based on multi-DCI may be read interchangeably with each other. In the present disclosure, multi-TRP based on multi-DCI, setting one CORESET pool index (CORESETPoolIndex) value for CORESET may be read interchangeably with each other. In the present disclosure, multi-TRP based on single DCI, mapping at least one code point of the TCI field to two TCI states may be read interchangeably with each other.

[0152] In the present disclosure, TRP#1 (the first TRP) may correspond to CORESET pool index = 0, or may correspond to the first TCI state among two TCI states corresponding to one code point of the TCI field. TRP#2 (the second TRP) and TRP#1 (the first TRP) may correspond to CORESET pool index = 1, or may correspond to the second TCI state among two TCI states corresponding to one code point of the TCI field.

[0153] In the present disclosure, single DCI (sDCI), single PDCCH, a multi-TRP system based on single DCI, sDCI-based MTRP, and activation of two TCI states on at least one TCI code point may be read interchangeably with each other.

[0154] In the present disclosure, multi DCI (mDCI), multi PDCCH, a multi-TRP system based on multi DCI, mDCI-based MTRP, and setting of two CORESET pool indexes or CORESET pool index = 1 (or one or more values) may be read interchangeably with each other.

[0155] In the present disclosure, receiving a DL signal (PDSCH / PDCCH) using an SFN may mean receiving the same time / frequency resource and / or the same data (PDSCH) / control information (PDCCH) from multiple transmit / receive points. Also, receiving a DL signal using an SFN may mean receiving the same time / frequency resource and / or the same data / control information using multiple TCI states / space domain filters / beams / QCLs.

[0156] In the present disclosure, the HST-SFN scheme, the SFN scheme after Rel. 17, the new SFN scheme, the new HST-SFN scheme, the HST-SFN scenario after Rel. 17, the HST-SFN scheme for the HST-SFN scenario, the SFN scheme for the HST-SFN scenario, Scheme 1, the Doppler pre-compensation scheme, Scheme 1 (HST Scheme 1), and at least one of the Doppler pre-compensation schemes may be read interchangeably with each other. In the present disclosure, the Doppler pre-compensation scheme, the base station pre-compensation scheme, the TRP pre-compensation scheme, the pre-Doppler compensation scheme, the Doppler pre-compensation scheme, the NW pre-compensation scheme, the HST NW pre-compensation scheme may be read interchangeably with each other. In the present disclosure, the pre-compensation scheme, the reduction scheme, the improvement scheme, and the correction scheme may be read interchangeably with each other.

[0157] In the present disclosure, the new ID, the TRP-ID, the group ID, and the CORESET pool index may be read interchangeably with each other. In the present disclosure, the first value of the new ID, the value 0 of the new ID, and the first TCI state among the two TCI states may be read interchangeably with each other. In the present disclosure, the second value of the new ID, the value 1 of the new ID, and the second TCI state among the two TCI states may be read interchangeably with each other.

[0158] In the present disclosure, two linked PDCCHs (PDCCH candidates), two linked search space (SS) sets, two linked CORESETs, two linked SS sets for PDCCH repetition, two linked PDCCHs for PDCCH repetition, two PDCCH candidates associated with two linked SS sets, two linked CORESETs for PDCCH repetition, and two CORESETs respectively associated with two linked SS sets may be read interchangeably with each other.

[0159] A plurality of SS sets (SS set pairs) having a linkage may mean that, via an RRC IE / MAC CE for PDCCH repetition, one SS set is linked to another SS set. An SS set having no linkage (an individual SS set) may mean that, via an RRC IE / MAC CE, that SS set is not linked to another SS set.

[0160] In the present disclosure, linked, having a linkage, pair may be read interchangeably with each other. In the present disclosure, unlinked, having no linkage, individual may be read interchangeably with each other.

[0161] In the present disclosure, per-cell BFR, one BFR-RS set is configured / associated for one cell, may be read interchangeably with each other. In the present disclosure, per-TRP BFR, up to two BFR-RS sets are configured / associated for one cell, the BFR-RS sets per TRP are configured / associated, may be read interchangeably with each other.

[0162] (Wireless communication method) The UE may receive a configuration (e.g., resource, resource list, etc.) indicating one or two BFD-RS sets (e.g., q 0 、q 0_0 、q 0_1 etc.) for the cell. The UE may evaluate the radio link quality using at least one of two TCI states associated with one CORESET or two PDCCHs and one or two BFD-RS sets.

[0163] The two TCI states may be associated with one CORESET / PDCCH. The two TCI states may be associated with two linked PDCCHs.

[0164] <First embodiment> This embodiment relates to cases #1 or #4 above.

[0165] The RRC IE / MAC CE has one BFD-RS set q 0 Here, as in the example in Figure 6, the set q 0 The question arises as to whether the two BFD-RSs in are QCL'd with one or two TCI states of the PDCCH / CORESET.

[0166] Set Q 0 The BFD-RS (e.g., SS / PBCH blocks or P-CSI-RS resources) in may obey at least one of the following QCL relationships 1 to 4. [QCL relation 1] Set q 0 The BFD-RS in the SFN-CORESET is QCL'd with the DM-RS (TCI state) of the PDCCH / CORESET with only one TCI state. The BFD-RS in the SFN-CORESET is QCL'd with the DM-RS (TCI state) of the PDCCH / CORESET with only one TCI state. [QCL Relation 2] If a PDCCH / CORESET is activated with one TCI state, then set q 0 The BFD-RS in is QCL'd with the DM-RS (TCI state) of that PDCCH / CORESET, or with the first (or second) TCI state of that PDCCH / CORESET if the DM-RS of the PDCCH / CORESET is activated with two TCI states. [QCL Relation 3] Set q 0 The BFD-RS in is QCL'd with the first (or second) TCI state of the PDCCH / CORESET activated with two TCI states. [QCL Relation 4] Set q 0 The two BFD-RSs in are QCL'd with two TCI states of the activated PDCCH / CORESET, respectively, with two TCI states, which may be the SFN-CORESET.

[0167] Set Q 0When the UE evaluates the radio link quality according to the BFD-RS QCLed with the DM-RS of the PDCCH, the UE may follow at least one of the following Operations 1 to 3.

[0168] [Operation 1] If the PDCCH / CORESET is associated with only one TCI state, the UE follows the Rel.16 operation described above.

[0169] [Operation 2] If the PDCCH / CORESET is associated with two TCI states and one of the BFD-RSs in the set is QCLed with the first (or second) TCI state of the CORESET, the UE assumes either of the following Assumptions 1 and 2 and evaluates one radio link quality for the PDCCH / CORESET. [[Assumption 1]] Reception from the first (or second) TCI state (using the first (or second) TCI state). [[Assumption 2]] SFN reception from both TCI states (using both TCI states).

[0170] [Operation 3] If the PDCCH / CORESET is associated with two TCI states and the two BFD-RSs in the set are respectively QCLed with the two TCI states of the CORESET, the UE follows at least one of the following Evaluations 1 and 2.

[0171] [[Evaluation 1]] The UE assumes either of the following Assumptions 1 and 2 and evaluates one radio link quality for the PDCCH / CORESET. [[Assumption 1]] Reception from the first (or second) TCI state (using the first (or second) TCI state). [[Assumption 2]] SFN reception from both TCI states (using both TCI states).

[0172] [[Evaluation 2]] The UE assumes reception from each TCI state (using each TCI state) and evaluates two radio link qualities for that PDCCH / CORESET.

[0173] According to this embodiment, the UE can appropriately use one indicated BFD-RS set for each cell's BFR.

[0174] <Second Embodiment> This embodiment relates to the aforementioned case #5.

[0175] 《Aspect 2-A》 The RRC IE / MAC CE may set / update two BFD-RS sets q 0_0 , q 0_1 . Here, as in the example of FIG. 7, it becomes a problem which of the two BFD-RSs in set q 0_0 and the two BFD-RSs in set q 0_1 are QCL with one or two TCI states of the PDCCH / CORESET.

[0176] In the present disclosure, set q 0_0 may be associated with the first TRP ID / CORESET pool index / group ID / new ID (for example, value 0). Set q 0_1 may be associated with the second TRP ID / CORESET pool index / group ID / new ID (for example, value 1).

[0177] The BFD-RSs (for example, SS / PBCH block or P-CSI-RS resource) in sets q 0_0 , q 0_1 may follow the following QCL relationship. [QCL Relationship] The BFD-RSs in set q 0_0 are QCL with the first TCI state of the PDCCH / CORESET activated with two TCI states. The BFD-RSs in set q 0_1 are QCL with the second TCI state of that PDCCH / CORESET activated with two TCI states.

[0178] A CORESET activated with one TCI state may follow any of the following CORESET1 to 3. [CORESET1] When the SFN is configured, such a CORESET (a CORESET with at least a UE-specific search space (USS) (including), or a CORESET without (not including) at least a common search space (CSS) type) does not exist. [CORESET2] Such a CORESET exists, but is not considered in the above QCL relationship for BFD-RS. [CORESET3] Such a CORESET exists and is considered in the above QCL relationship for BFD-RS in any set.

[0179] Set q 0_0 , q 0_1 For each set of q [Evaluation] If the PDCCH / CORESET has two TCI states and the sets q 0_0 and q 0_1 are QCLed with the first and second TCI states of the CORESET respectively, the UE may evaluate the radio link quality for the PDCCH / CORESET according to either of the following Evaluations 1 and 2. [[Evaluation 1]] The UE assumes reception from each TCI state (using each TCI state) and evaluates two radio link qualities for each TRP / set. [[Evaluation 2]] The UE assumes SFN reception from both TCI states (using both TCI states) and evaluates the same one radio link quality or two radio link qualities.

[0180] <<Aspect 2-B>> Each CORESET is associated with a new ID. Each CORESET is within one of two groups corresponding to two values of the new ID.

[0181] As in the example of FIG. 8, if one CORESET is activated with two TCI states, the problem is how to place (associate) that CORESET within one of the groups. The CORESET may follow any of the following associations 1 to 3. [Association 1] There is no group indication / association for a CORESET with two TCI states. [Association 2] For a CORESET with two TCI states, a fixed group (e.g., group #0) is indicated / associated. [Association 3] There is no restriction on the group indication / association for a CORESET with two TCI states.

[0182] The RRC IE / MAC CE may configure / update two BFD-RS sets q 0_0 , q 0_1 . Here, as in the example of FIG. 8, the problem is which of the one or two TCI states of the PDCCH / CORESET the two BFD-RS in set q 0_0 and the two BFD-RS in set q 0_1 are QCL with.

[0183] Set q 0_0 , q 0_1 The BFD-RS (e.g., SS / PBCH block or P-CSI-RS resource) within may follow either of the following QCL relationships 1 and 2.

[0184] [QCL Relationship 1] The BFD-RS within set q 0_0 may be QCL with the first TCI state of the PDCCH / CORESET activated with two TCI states, or that TCI state of the PDCCH / CORESET activated with one TCI state within the first group (group #0). Set q0_1 The BFD-RS inside may be QCL with the first TCI state of the PDCCH / CORESET activated with two TCI states, or that TCI state of the PDCCH / CORESET activated with one TCI state within the second group (group #1).

[0185] [QCL Relationship 2] Set q 0_0 The BFD-RS inside may be QCL with the first TCI state of the PDCCH / CORESET activated with two TCI states within the first group (group #0), or that TCI state of the PDCCH / CORESET activated with one TCI state within the first group (group #0). Set q 0_1 The BFD-RS inside may be QCL with the first TCI state of the PDCCH / CORESET activated with two TCI states within the second group (group #1), or that TCI state of the PDCCH / CORESET activated with one TCI state within the second group (group #1).

[0186] Set q 0_0 , q 0_1 For each set of, when the UE evaluates the radio link quality according to the BFD-RS QCL with the PDCCH, the UE may follow the following evaluation. [Evaluation] If the PDCCH / CORESET has two TCI states and set q 0_0 (or q 0_1 ) is QCL with one TCI state of the CORESET, the UE evaluates the radio link quality for the PDCCH / CORESET according to either of the following Evaluations 1 and 2. [[Evaluation 1]] The UE assumes reception from the corresponding TCI state (using the corresponding TCI state) and evaluates the radio link quality for the corresponding TRP / set. [[Evaluation 2]] The UE assumes SFN reception from both TCI states (using both TCI states) and evaluates the radio link quality.

[0187] 《Aspect 2-C》 Each TCI state is associated with a new ID. Each TCI state is within one of two groups corresponding to two values of the new ID.

[0188] For one CORESET activated with two TCI states, as in the example of FIG. 9, those two TCI states are assumed to be within different groups (group #0, #1).

[0189] The RRC IE / MAC CE may configure / update two BFD-RS sets q 0_0 , q 0_1 . Here, the problem is which of the two BFD-RS within set q 0_0 and the two BFD-RS within set q 0_1 are QCL with one or two TCI states of the PDCCH / CORESET.

[0190] Set q 0_0 , q 0_1 The BFD-RS (e.g., SS / PBCH block or P-CSI-RS resource) within may follow the following QCL relationship.

[0191] [QCL relationship] The BFD-RS within set q 0_0 is QCL with the TCI state of its PDCCH / CORESET. Here, the TCI state is the TCI state from the first group (group #0). The BFD-RS within set q 0_1 is QCL with the TCI state of its PDCCH / CORESET. Here, the TCI state is the TCI state from the second group (group #1).

[0192] The RRC IE may configure whether each RS within each TCI state can be used / set for BFD. The RRC IE may configure the associated BFD-RS for such RSs for BFD within each TCI state.

[0193] Set q 0_0 , q 0_1 For each set of 0_0 , q 0_1 , when the UE evaluates the radio link quality according to the BFD-RS QCLed with the PDCCH, the UE may follow the following evaluation. [Evaluation] If the PDCCH / CORESET is associated with two TCI states, and set q 0_0 (or q 0_1 ) is QCLed with one TCI state of the CORESET from the corresponding group, the UE evaluates the radio link quality for the PDCCH / CORESET according to either of the following Evaluations 1 and 2. [[Evaluation 1]] The UE assumes reception from the corresponding TCI state within the same group (using the corresponding TCI state within the same group) and evaluates the radio link quality for the corresponding TRP / set. [[Evaluation 2]] The UE assumes SFN reception from both TCI states (using both TCI states) and evaluates the radio link quality.

[0194] 《Analysis》 In single DCI-based multi-TRP, the grouping of TCI states appears clearer than the grouping of CORESETs and is also preferable in differentiating from multi-DCI-based multi-TRP.

[0195] The RRC configuration of whether each RS within each TCI state can be used / set for BFD may be applied to the aforementioned Case #1 / #4.

[0196] 《Aspect 2-D》 Regarding the SFN-PDCCH, how the calculation is performed using the BFD-RS from two TRPs may depend on the UE implementation.

[0197] For the SFN-PDCCH, it may be difficult to support BFR per TRP, and only BFR per cell may be supported. For BFR per TRP, the UE may be specified not to assume using explicit / implicit BFD-RS associated with (QCLed to) a CORESET with two TCI states.

[0198] For two linked PDCCHs, explicit / implicit BFD-RS for BFR per TRP may be supported.

[0199] According to this embodiment, the UE can appropriately use one or two indicated BFD-RS sets for BFR per TRP.

[0200] <The Third Embodiment> This embodiment relates to the aforementioned cases #a, #b, #d.

[0201] In the first embodiment, the first / second TCI state of the CORESET / PDCCH with two TCI states (two TCI states associated with the CORESET / PDCCH) may be read as the TCI state of the first / second PDCCH of two linked PDCCHs.

[0202] According to this embodiment, the UE can appropriately use one or two indicated BFD-RS sets for BFR per cell.

[0203] <The Fourth Embodiment> This embodiment relates to the aforementioned case #c.

[0204] In the second embodiment, the first / second TCI state of the CORESET / PDCCH (two TCI states associated with the CORESET / PDCCH) with two TCI states may be read as the TCI state of the first / second PDCCH of the two linked PDCCHs.

[0205] According to this embodiment, the UE can appropriately use the indicated one or two BFD-RS sets for the BFR per TRP.

[0206] <Fifth Embodiment> This embodiment relates to the aforementioned case #e.

[0207] The RRC IE / MAC CE may set / update two BFD-RS sets q 0_0 , q 0_1 .

[0208] Set q 0_0 , q 0_1 The BFD-RS (e.g., SS / PBCH block or P-CSI-RS resource) within may follow either of the following QCL relationships 1 and 2.

[0209] [QCL Relationship 1] The UE assumes that the CORESETs of the two linked PDCCHs belong to (are associated with) the same CORESET pool index. The BFD-RS within set q 0_0 is QCL with the CORESET from CORESET pool index = 0. The BFD-RS within set q 0_1 is QCL with the CORESET from CORESET pool index = 1. The two linked PDCCHs that are QCL with the BFD-RS may be within the same BFD-RS set.

[0210] [QCL Relationship 2] The UE assumes that the CORESETs of the two linked PDCCHs are associated with different CORESET pool indexes. The set q 0_0The BFD-RS within is QCLed with the CORESET from CORESET pool index = 0. Set q 0_1 The BFD-RS within is QCLed with the CORESET from CORESET pool index = 1. Two linked PDCCHs QCLed with the BFD-RS may be in different BFD-RS sets.

[0211] According to this embodiment, the UE can appropriately use the indicated one or two BFD-RS sets for the BFR per TRP.

[0212] <Other embodiments> 《UE capability information / Upper layer parameters》 Upper layer parameters (RRC IE) / UE capabilities corresponding to the functions (features) in each of the above embodiments may be defined. The upper layer parameters may indicate whether to enable the function. The UE capabilities may indicate whether the UE supports the function.

[0213] A UE with the upper layer parameters corresponding to the function set may perform the function. It may be defined that "a UE without the upper layer parameters corresponding to the function set does not perform the function (e.g., according to Rel.15 / 16)".

[0214] A UE that reports / sends UE capabilities indicating support for the function may perform the function. It may be defined that "a UE that does not report UE capabilities indicating support for the function does not perform the function (e.g., according to Rel.15 / 16)".

[0215] If the UE reports / sends UE capabilities indicating that it supports the function and the upper layer parameters corresponding to the function are set, the UE may perform the function. It may be specified that "if the UE does not report / send UE capabilities indicating that it supports the function or the upper layer parameters corresponding to the function are not set, the UE does not perform the function (e.g., in accordance with Rel.15 / 16)".

[0216] Among the above - mentioned multiple embodiments, which embodiment / option / choice / function is used may be set by upper layer parameters, reported by the UE as UE capabilities, specified in the specification, or determined by the reported UE capabilities and the setting of upper layer parameters.

[0217] The UE capabilities may indicate whether the UE supports at least one of the following functions. · An explicit BFD - RS set for per - cell BFR is QCL with a CORESET (one or two TCI states of the CORESET) with two TCI states. · For the setting of two explicit BFD - RS sets for per - TRP BFR, the BFD - RS within each set is QCL with one TCI state of a CORESET with two TCI states (for single DCI - based multi - TRP). · Two CORESETs are grouped / associated into two groups (for single DCI - based multi - TRP). · Grouping is performed for a CORESET with two TCI states. · Two TCI states are grouped / associated into two groups (for single DCI - based multi - TRP). · When one CORESET has two TCI states, grouping is performed. · When the UE evaluates the radio link quality of its PDCCH / CORESET for a CORESET with two TCI states, the UE follows the following assumptions 1 and 2. [Scenario 1] The UE assumes reception from one / each TCI state (using one / each TCI state). [Scenario 2] The UE assumes SFN reception from both TCI states (using both TCI states). · Different numbers (e.g., 1 and 2) of TCI states are activated for multiple CORESETs. The UE capability indicating support for this function may indicate whether CORESET0 is included or excluded. This function may be supported for SFN - PDCCH. · PDCCH repetition is performed using two linked PDCCH / PDCCH candidates / SS sets.

[0218] According to the above UE capabilities / upper layer parameters, the UE can implement the above functions while maintaining compatibility with existing specifications.

[0219] (Wireless communication system) Hereinafter, the configuration of a wireless communication system according to an embodiment of the present disclosure will be described. In this wireless communication system, communication is performed using any one or a combination of the wireless communication methods according to the above embodiments of the present disclosure.

[0220] FIG. 10 is a diagram showing an example of the 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) standardized by the Third Generation Partnership Project (3GPP), 5th generation mobile communication system New Radio (5G NR), etc.

[0221] In addition, the wireless communication system 1 may support dual connectivity (Multi-RAT Dual Connectivity (MR-DC)) between multiple Radio Access Technologies (RATs). 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)), and the like.

[0222] In EN-DC, the base station (eNB) of LTE (E-UTRA) is the Master Node (MN), and the base station (gNB) of NR is the Secondary Node (SN). In NE-DC, the base station (gNB) of NR is the MN, and the base station (eNB) of LTE (E-UTRA) is the SN.

[0223] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, NR-NR Dual Connectivity (NN-DC) where both the MN and the SN are base stations (gNBs) of NR).

[0224] The wireless communication system 1 may include a base station 11 that forms a relatively wide-coverage macro cell C1, and a base station 12 (12a - 12c) that is disposed within the macro cell C1 and forms a small cell C2 that is narrower than the macro cell C1. The user terminal 20 may be located within at least one cell. The arrangement, number, etc. of each cell and the user terminal 20 are not limited to the modes shown in the figure. Hereinafter, when the base stations 11 and 12 are not distinguished, they are collectively referred to as the base station 10.

[0225] The user terminal 20 may be connected to at least one of the plurality of base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) and dual connectivity (DC) using a plurality of component carriers (CCs).

[0226] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). Note that the frequency bands, definitions, etc. of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a frequency band higher than FR2.

[0227] Also, the user terminal 20 may communicate using at least one of time division duplex (TDD) and frequency division duplex (FDD) in each CC.

[0228] The plurality of base stations 10 may be connected by wire (for example, an optical fiber compliant with Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (for example, NR communication). For example, when NR communication is used as a backhaul between base stations 11 and 12, the base station 11 corresponding to the upper-level 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.

[0229] The base station 10 may be connected to the core network 30 via another base station 10 or directly. The core network 30 may include at least one of, for example, Evolved Packet Core (EPC), 5G Core Network (5GCN), Next Generation Core (NGC), etc.

[0230] The user terminal 20 may be a terminal corresponding to at least one of communication systems such as LTE, LTE-A, 5G, etc.

[0231] In the wireless communication system 1, an orthogonal frequency division multiplexing (OFDM)-based wireless access method may be used. For example, in at least one of the downlink (DL) and the uplink (UL), 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), etc. may be used.

[0232] The wireless access method may be referred to as a waveform. Note that in the wireless communication system 1, other wireless access methods (for example, other single carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL wireless access methods.

[0233] In the wireless communication system 1, as downlink channels, a Physical Downlink Shared Channel (PDSCH) shared by each user terminal 20, a Physical Broadcast Channel (PBCH), a Physical Downlink Control Channel (PDCCH), etc. may be used.

[0234] Also, in the wireless communication system 1, as uplink channels, a Physical Uplink Shared Channel (PUSCH) shared by each user terminal 20, a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH), etc. may be used.

[0235] User data, upper layer control information, a System Information Block (SIB), etc. are transmitted by the PDSCH. User data, upper layer control information, etc. may be transmitted by the PUSCH. Also, a Master Information Block (MIB) may be transmitted by the PBCH.

[0236] 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.

[0237] Note that the DCI for scheduling the PDSCH may be called DL assignment, DL DCI, etc., and the DCI for scheduling the PUSCH may be called UL grant, UL DCI, etc. Note that the PDSCH may be read as DL data, and the PUSCH may be read as UL data.

[0238] For PDCCH detection, a control resource set (CORESET) and a search space may be used. The CORESET corresponds to the resources for searching for DCI. The search space corresponds to the search area and search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

[0239] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the "search space", "search space set", "search space configuration", "search space set configuration", "CORESET", "CORESET configuration", etc. in the present disclosure may be mutually substituted.

[0240] Uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (e.g., may be referred to as Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR) may be transmitted by PUCCH. A random access preamble for connection establishment with the cell may be transmitted by PRACH.

[0241] Note that in the present disclosure, downlink, uplink, etc. may be expressed without adding "link". Also, "Physical" may be omitted at the beginning of various channels.

[0242] In the wireless communication system 1, a synchronization signal (Synchronization Signal (SS)), a downlink reference signal (Downlink Reference Signal (DL-RS)), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (Cell-specific Reference Signal (CRS)), a channel state information reference signal (Channel State Information Reference Signal (CSI-RS)), a demodulation reference signal (DeModulation Reference Signal (DMRS)), a positioning reference signal (Positioning Reference Signal (PRS)), a phase tracking reference signal (Phase Tracking Reference Signal (PTRS)), etc. may be transmitted.

[0243] The synchronization signal may be, for example, at least one of a primary synchronization signal (Primary Synchronization Signal (PSS)) and a secondary synchronization signal (Secondary Synchronization Signal (SSS)). A signal block including SS (PSS, SSS) and PBCH (and DMRS for PBCH) may be called an SS / PBCH block, an SS Block (SSB), etc. Note that SS, SSB, etc. may also be called reference signals.

[0244] Also, in the wireless communication system 1, as the uplink reference signal (Uplink Reference Signal (UL-RS)), a sounding reference signal (Sounding Reference Signal (SRS)), a demodulation reference signal (DMRS), etc. may be transmitted. Note that DMRS may also be called a UE-specific reference signal.

[0245] (Base station) FIG. 11 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 transmission / reception unit 120, a transmission / reception antenna 130, and a transmission line interface 140. Note that one or more of the control unit 110, the transmission / reception unit 120, the transmission / reception antenna 130, and the transmission line interface 140 may be provided.

[0246] Note that in this example, the functional blocks of the characteristic portions in the present embodiment are mainly shown, and the base station 10 may be assumed to have other functional blocks necessary for wireless communication. Some of the processes of each unit described below may be omitted.

[0247] The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, a control circuit, etc., which are described based on the common knowledge in the technical field related to the present disclosure.

[0248] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission / reception, measurement, etc., using the transmission / reception unit 120, the transmission / reception antenna 130, and the transmission line interface 140. The control unit 110 may generate data, control information, a sequence, etc., to be transmitted as a signal, and transfer it to the transmission / reception unit 120. The control unit 110 may perform call processing (setting, release, etc.) of a communication channel, state management of the base station 10, management of radio resources, etc.

[0249] The transmission / reception 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 transmission / reception unit 120 can be composed of a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transmission / reception circuit, etc., which are described based on the common knowledge in the technical field related to the present disclosure.

[0250] The transceiver unit 120 may be configured as an integrated transceiver unit, or may be composed of a transmitter unit and a receiver unit. The transmitter unit may be composed of a transmission processing unit 1211 and an RF unit 122. The receiver unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0251] The transceiver antenna 130 can be composed of an antenna described based on the common understanding in the technical field related to the present disclosure, such as an array antenna.

[0252] The transceiver unit 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver unit 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0253] The transceiver unit 120 may form at least one of a transmission beam and a reception beam by using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), etc.

[0254] The transceiver unit 120 (transmission processing unit 1211) may perform processing of the Packet Data Convergence Protocol (PDCP) layer, processing of the Radio Link Control (RLC) layer (for example, RLC retransmission control), processing of the Medium Access Control (MAC) layer (for example, HARQ retransmission control), etc. on, for example, data and control information obtained from the control unit 110, and generate a bit sequence to be transmitted.

[0255] The transmission / reception unit 120 (transmission processing unit 1211) may perform transmission processing such as channel encoding (which may include error correction encoding), 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 sequence to be transmitted, and output a baseband signal.

[0256] The transmission / reception unit 120 (RF unit 122) may perform modulation to the radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmission / reception antenna 130.

[0257] On the other hand, the transmission / reception unit 120 (RF unit 122) may perform amplification, filtering, demodulation to the baseband signal, etc. on the radio frequency band signal received by the transmission / reception antenna 130.

[0258] The transmission / reception unit 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 on the acquired baseband signal, and acquire user data, etc.

[0259] The transmission / reception unit 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.

[0260] The transmission path interface 140 may transmit and receive signals (backhaul signaling) with 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.

[0261] Note that the transmission unit and reception unit of the base station 10 in the present disclosure may be configured by at least one of the transmission / reception unit 120, the transmission / reception antenna 130, and the transmission path interface 140.

[0262] Note that the transmission / reception unit 120 may transmit a setting indicating one or two sets of beam failure detection reference signals (BFD-RS) for the cell. The control unit 110 may control the reception of results based on the radio link quality evaluated using at least one of one control resource set or two Transport Format Combination Indicator (TCI) states associated with two Physical Downlink Control Channels (PDCCH) and the one or two BFD-RS sets.

[0263] (User Terminal) FIG. 12 is a diagram showing an example of the configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transmission / reception unit 220, and a transmission / reception antenna 230. Note that one or more of the control unit 210, the transmission / reception unit 220, and the transmission / reception antenna 230 may be provided.

[0264] Note that in this example, the functional blocks of the characteristic portions in the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. A part of the processing of each unit described below may be omitted.

[0265] The control unit 210 controls the entire user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on the common knowledge in the technical field related to the present disclosure.

[0266] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission, reception, measurement, etc. using the transmission / reception unit 220 and the transmission / reception antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transmission / reception unit 220.

[0267] The transmission / reception 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 transmission / reception unit 220 can be configured from a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transmission / reception circuit, etc., which are described based on the common knowledge in the technical field related to the present disclosure.

[0268] The transmission / reception unit 220 may be configured as an integrated transmission / reception unit or may be configured from a transmission unit and a reception unit. The transmission unit may be configured from the transmission processing unit 2211 and the RF unit 222. The reception unit may be configured from the reception processing unit 2212, the RF unit 222, and the measurement unit 223.

[0269] The transmission / reception antenna 230 can be composed of an antenna described based on the common understanding in the technical field related to the present disclosure, such as an array antenna or the like.

[0270] The transmission / reception unit 220 may receive the above-described downlink channel, synchronization signal, downlink reference signal, etc. The transmission / reception unit 220 may transmit the above-described uplink channel, uplink reference signal, etc.

[0271] The transmission / reception unit 220 may form at least one of a transmission beam and a reception beam by using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0272] The transmission / reception unit 220 (transmission processing unit 2211) may perform processing of the PDCP layer, processing of the RLC layer (e.g., RLC retransmission control), processing of the MAC layer (e.g., HARQ retransmission control), etc. on data, control information, etc. acquired from the control unit 210, for example, and generate a bit string to be transmitted.

[0273] The transmission / reception unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, digital-to-analog conversion, etc. on the bit string to be transmitted, and output a baseband signal.

[0274] Whether or not to apply DFT processing may be based on the setting of transform precoding. For a certain channel (e.g., PUSCH), when transform precoding is enabled, the transmission / reception unit 220 (transmission processing unit 2211) may perform DFT processing as the above-described transmission processing to transmit the channel using the DFT-s-OFDM waveform, or otherwise, it may not perform DFT processing as the above-described transmission processing.

[0275] The transmission / reception unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the signal in the radio frequency band via the transmission / reception antenna 230.

[0276] On the other hand, the transmission / reception unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the signal in the radio frequency band received by the transmission / reception antenna 230.

[0277] The transmission / reception unit 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0278] The transmission / reception unit 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), reception 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.

[0279] Note that the transmission unit and reception unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmission / reception unit 220 and the transmission / reception antenna 230.

[0280] Note that the transmission / reception unit 220 may receive a setting indicating one or two sets of beam failure detection reference signals (BFD-RS) for a cell. The control unit 210 may evaluate the radio link quality using at least one of one control resource set or two transmission control indicator (TCI) states associated with two physical downlink control channels (PDCCH), and the one or two BFD-RS sets.

[0281] The setting may indicate two BFD-RS sets. The two BFD-RS sets may be respectively associated with the two TCI states.

[0282] The one control resource set may be associated with the two TCI states.

[0283] The two PDCCHs may be respectively associated with the two TCI states. The two PDCCHs may be linked to each other.

[0284] (Hardware Configuration) Note that the block diagrams used in the description of the above embodiments show blocks of functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Also, the realization method of each functional block is not particularly limited. That is, each functional block may be realized using one physically or logically combined device, or two or more physically or logically separated devices may be directly or indirectly (for example, using wired, wireless, etc.) connected and realized using these multiple devices. The functional block may be realized by combining software with the above one device or the above multiple devices.

[0285] Here, functions include, but are not limited to, judgment, decision, determination, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, regarded as, notification (broadcasting), notification (notifying), communication, forwarding, configuration, reconfiguration, allocation (allocating, mapping), assignment, etc. For example, a functional block (component) that enables transmission may be referred to as a transmitting unit, a transmitter, etc. In any case, as described above, the realization method is not particularly limited.

[0286] For example, a base station, a user terminal, etc. in an embodiment of the present disclosure may function as a computer that performs the processing of the wireless communication method of the present disclosure. FIG. 13 is a diagram showing 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 physically be 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, and the like.

[0287] In the present disclosure, terms such as device, circuit, device, section, unit, etc. can be read interchangeably with each other. The hardware configuration of the base station 10 and the user terminal 20 may be configured to include one or more of each device shown in the figure, or may be configured without including some devices.

[0288] For example, although only one processor 1001 is shown, there may be a plurality of processors. Also, the processing may be executed by one processor, or the processing may be executed by two or more processors simultaneously, sequentially, or using other methods. Note that the processor 1001 may be implemented by one or more chips.

[0289] Each function in the base station 10 and the user terminal 20 is realized, for example, by causing a predetermined software (program) to be loaded onto hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs calculations and controls communication via the communication device 1004, or controls at least one of reading and writing data in the memory 1002 and the storage 1003.

[0290] Processor 1001 controls the entire computer by operating, for example, an operating system. Processor 1001 may be constituted by a Central Processing Unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, registers, and the like. For example, at least a part of the above-described control unit 110 (210), transmission / reception unit 120 (220), etc. may be realized by processor 1001.

[0291] Also, processor 1001 reads a program (program code), software module, data, etc. from at least one of storage 1003 and communication device 1004 into memory 1002, and executes various processes according to these. As the program, a program for causing a computer to execute at least a part of the operations described in the above embodiments is used. For example, control unit 110 (210) may be realized by a control program stored in memory 1002 and operating in processor 1001, and the same may apply to other functional blocks.

[0292] Memory 1002 is a computer-readable recording medium, and may be constituted by, for example, at least one of Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EPROM (EEPROM), Random Access Memory (RAM), and other appropriate storage media. Memory 1002 may be referred to as a register, cache, main memory (main storage device), etc. Memory 1002 can store a program (program code), software module, etc. executable for implementing the wireless communication method according to an embodiment of the present disclosure.

[0293] Storage 1003 is a computer-readable recording medium and may be composed of, for example, at least one of a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (e.g., a compact disk such as a Compact Disc ROM (CD-ROM), a digital versatile disk, a Blu-ray (registered trademark) disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, and other suitable storage media. Storage 1003 may be referred to as an auxiliary storage device.

[0294] Communication device 1004 is hardware (a transmission / reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. Communication device 1004 may be configured to include, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. in order to implement at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, the above-described transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be implemented by communication device 1004. The transmission / reception unit 120 (220) may be physically or logically separated and implemented by a transmission unit 120a (220a) and a reception unit 120b (220b).

[0295] Input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives external input. Output device 1006 is an output device (e.g., a display, a speaker, a Light Emitting Diode (LED) lamp, etc.) that performs output to the outside. Note that input device 1005 and output device 1006 may have an integrated configuration (e.g., a touch panel).

[0296] Also, 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 for each device.

[0297] Also, 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), and a Field Programmable Gate Array (FPGA), and some or all of the functional blocks may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0298] (Modification example) In addition, terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, channel, symbol, and signal (signal or signaling) may be read interchangeably with each other. Also, a signal may be a message. A reference signal may also be abbreviated as RS and may be called a pilot, a pilot signal, etc. depending on the applicable standard. Also, a Component Carrier (CC) may be called a cell, a frequency carrier, a carrier frequency, etc.

[0299] A wireless frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting the wireless frame may be called a subframe. Further, a subframe may be composed of one or more slots in the time domain. The subframe may have a fixed time length (e.g., 1 ms) independent of numerology.

[0300] Here, numerology may be a communication parameter applied to at least one of transmission and reception of a certain signal or channel. Numerology may indicate, for example, at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, wireless frame configuration, specific filtering processing performed by a transceiver in the frequency domain, specific windowing processing performed by a transceiver in the time domain, etc.

[0301] A slot may be composed of one or more symbols (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) in the time domain. Also, a slot may be a time unit based on numerology.

[0302] The slot may include a plurality of mini-slots. Each mini-slot may be composed of one or more symbols in the time domain. Also, the mini-slot may be called a sub-slot. The mini-slot may be composed of a smaller number of symbols than the slot. The PDSCH (or PUSCH) transmitted in a time unit larger than the mini-slot may be called PDSCH (PUSCH) mapping type A. The PDSCH (or PUSCH) transmitted using the mini-slot may be called PDSCH (PUSCH) mapping type B.

[0303] The radio frame, sub-frame, slot, mini-slot, and symbol all represent time units when transmitting signals. Different names corresponding to each of them may be used. Note that the time units such as frames, sub-frames, slots, mini-slots, and symbols in the present disclosure may be read interchangeably with each other.

[0304] For example, one sub-frame may be called a TTI, or a plurality of consecutive sub-frames may be called a TTI, or one slot or one mini-slot may be called a TTI. That is, at least one of the sub-frame and the TTI may be the sub-frame (1 ms) in the existing LTE, or 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, a mini-slot, etc. instead of a sub-frame.

[0305] Here, the TTI refers to, for example, the minimum time unit of scheduling in wireless communication. For example, in the LTE system, the base station performs scheduling to allocate radio resources (frequency bandwidth, transmission power, etc. that can be used in each user terminal) to each user terminal in units of TTI. Note that the definition of the TTI is not limited to this.

[0306] The TTI may be a transmission time unit such as a channel-coded data packet (transport block), code block, codeword, etc., or may be a processing unit such as scheduling and link adaptation. When the TTI is given, the time interval (e.g., number of symbols) in which a transport block, code block, codeword, etc. are actually mapped may be shorter than the TTI.

[0307] Note that when one slot or one mini-slot is called a TTI, one or more TTIs (i.e., one or more slots or one or more mini-slots) may be the minimum time unit for scheduling. Also, the number of slots (number of mini-slots) constituting the minimum time unit for the scheduling may be controlled.

[0308] A TTI having a time length of 1 ms may be called a normal TTI (TTI in 3GPP Rel.8-12), normal TTI, long TTI, normal subframe, normal subframe, long subframe, slot, etc. A TTI shorter than the normal TTI may be called a shortened TTI, short TTI, partial TTI (partial or fractional TTI), shortened subframe, short subframe, mini-slot, sub-slot, slot, etc.

[0309] Note that the long TTI (e.g., normal TTI, subframe, etc.) may be read as a TTI having a time length exceeding 1 ms, or the short TTI (e.g., shortened TTI, etc.) may be read as a TTI having a TTI length less than that of the long TTI and a TTI length of 1 ms or more.

[0310] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and in the frequency domain, it may include one or more consecutive subcarriers. The number of subcarriers included in an RB may be the same regardless of the numerology, for example, it may be 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0311] Also, an RB may include one or more symbols in the time domain, and may have a length of 1 slot, 1 mini-slot, 1 subframe, or 1 TTI. 1 TTI, 1 subframe, etc. may each be composed of one or more resource blocks.

[0312] Note that one or more RBs may be referred to as physical resource blocks (PRBs), sub-carrier groups (SCGs), resource element groups (REGs), PRB pairs, RB pairs, etc.

[0313] Also, a resource block may be composed of one or more resource elements (REs). For example, 1 RE may be a radio resource area of 1 subcarrier and 1 symbol.

[0314] A bandwidth part (BWP) (which may also be called a partial bandwidth, etc.) may represent a subset of consecutive common resource blocks (RBs) for a certain numerology in a certain carrier. Here, the common RB may be specified by the index of the RB based on the common reference point of the carrier. A PRB is defined in a certain BWP and may be numbered within that BWP.

[0315] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured within one carrier for a UE.

[0316] At least one of the configured BWPs may be active, and the UE may not be assumed to transmit and receive a predetermined signal / channel outside the active BWP. Note that "cell", "carrier", etc. in the present disclosure may be read as "BWP".

[0317] Note that the structures such as the radio frame, subframe, slot, mini-slot, and symbol described above 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 mini-slots included in a slot, the number of symbols and RBs included in a slot or mini-slot, the number of sub-carriers included in an RB, and the number of symbols, symbol length, cyclic prefix (CP) length, etc. within a TTI can be changed in various ways.

[0318] Also, the information, parameters, etc. described in the present disclosure may be represented using absolute values, relative values from a predetermined value, or corresponding other information. For example, a radio resource may be indicated by a predetermined index.

[0319] The names used for parameters, etc. in the present disclosure are not limiting names in any way. Furthermore, the mathematical formulas, etc. using these parameters may be different from those explicitly disclosed in the present disclosure. Since various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable names, the various names assigned to these various channels and information elements are not limiting names in any way.

[0320] 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.

[0321] Also, information, signals, etc. may be output from at least one of the upper layer to the lower layer and from the lower layer to the upper layer. Information, signals, etc. may be input and output via a plurality of network nodes.

[0322] The input and output information, signals, etc. may be stored in a specific location (e.g., memory) or may be managed using a management table. The input and output information, signals, etc. may be overwritten, updated, or appended. The output information, signals, etc. may be deleted. The input information, signals, etc. may be transmitted to other devices.

[0323] The notification of information is not limited to the aspects / embodiments described in this disclosure and may be performed using other methods. For example, the notification of information in this disclosure may be implemented by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), upper layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB), etc.), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0324] Note that physical layer signaling may also be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Also, RRC signaling may also be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc. Further, MAC signaling may be notified, for example, using a MAC Control Element (CE).

[0325] Also, the notification of predetermined information (for example, the notification of "being X") is not limited to an explicit notification, and may be performed implicitly (for example, by not performing the notification of the predetermined information or by the notification of another piece of information).

[0326] The determination may be made by a value represented by 1 bit (0 or 1), may be made by a boolean value represented by true or false, or may be made by a numerical comparison (for example, comparison with a predetermined value).

[0327] Software should be interpreted 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, execution threads, procedures, functions, etc., regardless of whether it is called software, firmware, middleware, microcode, a hardware description language, or by another name.

[0328] Also, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, when software is transmitted from a website, server, or other remote source using at least one of wired technologies (such as coaxial cable, optical fiber cable, twisted pair, Digital Subscriber Line (DSL), etc.) and wireless technologies (such as infrared, microwave, etc.), at least one of these wired and wireless technologies is included within the definition of the transmission medium.

[0329] The terms "system" and "network" as used in this disclosure may be used interchangeably. "Network" may mean the devices (such as base stations) included in the network.

[0330] In this disclosure, terms such as "precoding", "precoder", "weight (precoding weight)", "Quasi-Co-Location (QCL)", "Transmission Configuration Indication state (TCI state)", "spatial relation", "spatial domain filter", "transmission 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.

[0331] In the present disclosure, terms such as "Base Station (BS)", "radio base station", "fixed station", "NodeB", "eNB (eNodeB)", "gNB (gNodeB)", "access point", "Transmission Point (TP)", "Reception Point (RP)", "Transmission / Reception Point (TRP)", "panel", "cell", "sector", "cell group", "carrier", "component carrier" may be used interchangeably. The base station may also be referred to by terms such as macro cell, small cell, femto cell, pico cell, etc.

[0332] The base station can accommodate one or more (for example, three) cells. When the base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, and each of the smaller areas can also provide communication services by a base station subsystem (for example, a small indoor base station (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the whole of the coverage area of at least one of the base station and the base station subsystem that provides communication services in this coverage.

[0333] In the present disclosure, terms such as "Mobile Station (MS)", "user terminal", "User Equipment (UE)", "terminal" may be used interchangeably.

[0334] The 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 appropriate terms.

[0335] At least one of the base station and the mobile station may be referred to as a transmission device, a reception device, a wireless communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

[0336] The moving object refers to an object that can move, and the moving speed is arbitrary, and it naturally includes the case where the moving object is stopped. The moving object includes, for example, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, shovel cars, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, rear cars, rickshaws, ships (ship and other watercraft), airplanes, rockets, artificial satellites, drones, multicopters, quadcopters, balloons, and objects mounted on these, and is not limited thereto. Further, the moving object may be a moving object that autonomously travels based on an operation command.

[0337] The moving object may be a vehicle (for example, a car, an airplane, etc.), a moving object that moves without a person (for example, a drone, an autonomous driving vehicle, etc.), or a robot (humanoid or non-humanoid). Note that at least one of the base station and the mobile station also includes a device that does not necessarily move during a communication operation. 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.

[0338] FIG. 14 is a diagram showing an example of a vehicle according to an embodiment. As shown in FIG. 14, the vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, an axle 48, an electronic control unit 49, various sensors (including a current sensor 50, a rotation speed sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

[0339] The drive unit 41 is composed of, for example, at least one of an engine, a motor, and a hybrid of an engine and a motor. The steering unit 42 includes at least a steering wheel (also called a handwheel), and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by the user.

[0340] The electronic control unit 49 is composed of a microprocessor 61, a memory (ROM, RAM) 62, and a communication port (for example, an input / output (IO) port) 63. Signals from various sensors 50 - 58 provided in the vehicle are input to the electronic control unit 49. The electronic control unit 49 may be called an Electronic Control Unit (ECU).

[0341] Signals from various sensors 50 - 58 include a current signal from a current sensor 50 that senses the current of the motor, a rotational speed signal of the front wheels 46 / rear wheels 47 acquired by a rotational speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 acquired by an air pressure sensor 52, a vehicle speed signal acquired by a vehicle speed sensor 53, an acceleration signal acquired by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 acquired by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 acquired by a brake pedal sensor 56, an operation signal of the shift lever 45 acquired by a shift lever sensor 57, a detection signal for detecting obstacles, vehicles, pedestrians, etc. acquired by an object detection sensor 58, and so on.

[0342] The information service unit 59 is composed of various devices for providing various information such as driving information, traffic information, and entertainment information, such as a car navigation system, an audio system, a speaker, a display, a television, a radio, and one or more ECUs for controlling these devices. The information service unit 59 uses the information acquired from an external device via a communication module 60 or the like to provide various information / services (for example, multimedia information / multimedia services) to the passengers of the vehicle 40.

[0343] The driving assistance system unit 64 includes various devices for providing functions to prevent accidents or reduce the driver's driving load, such as a millimeter-wave radar, Light Detection and Ranging (LiDAR), a camera, a positioning locator (e.g., Global Navigation Satellite System (GNSS), etc.), map information (e.g., High Definition (HD) map, Autonomous Vehicle (AV) map, etc.), a gyro system (e.g., Inertial Measurement Unit (IMU), Inertial Navigation System (INS), etc.), an Artificial Intelligence (AI) chip, an AI processor, and one or more ECUs for controlling these devices. Further, the driving assistance system unit 64 transmits and receives various information via the communication module 60 to realize a driving assistance function or an autonomous driving function.

[0344] The communication module 60 can communicate with the microprocessor 61 and the components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 to the drive unit 41, the steering unit 42, the accelerator pedal 43, the brake pedal 44, the shift lever 45, the left and right front wheels 46, the left and right rear wheels 47, the axle 48, the microprocessor 61 and the memory (ROM, RAM) 62 in the electronic control unit 49, and various sensors 50 - 58 provided in the vehicle 40.

[0345] The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various types of information via wireless communication with the external device. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the above-described base station 10, user terminal 20, etc. Further, the communication module 60 may be, for example, at least one of the above-described base station 10 and user terminal 20 (it may function as at least one of the base station 10 and user terminal 20).

[0346] The communication module 60 may transmit at least one of the signals from the various sensors 50-58 and the information obtained based on the signals, which are input to the electronic control unit 49, to the external device via wireless communication.

[0347] The communication module 60 receives various types of information (traffic information, signal information, inter-vehicle information, etc.) transmitted from the external device and displays it on the information service unit 59 provided in the vehicle. Further, the communication module 60 stores the various types of information received from the external device in the memory 62 that can be used by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axle 48, various sensors 50-58, etc. provided in the vehicle 40.

[0348] In addition, the base station in the present disclosure may be replaced by a user terminal. For example, for a configuration in which communication between the base station and the user terminal is replaced by communication between a plurality of user terminals (which may be referred to as, for example, Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.), each aspect / embodiment of the present disclosure may be applied. In this case, the functions of the above-described base station 10 may be configured to be functions of the user terminal 20. Also, terms such as "uplink" and "downlink" may be replaced with terms corresponding to communication between terminals (for example, "sidelink"). For example, the uplink channel, the downlink channel, etc. may be replaced with the sidelink channel.

[0349] Similarly, the user terminal in the present disclosure may be replaced by a base station. In this case, the functions of the above-described user terminal 20 may be configured to be functions of the base station 10.

[0350] In the present disclosure, operations assumed to be performed by the base station may, in some cases, be performed by its upper node. In a network including one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal can be performed by the base station, one or more network nodes other than the base station (for example, Mobility Management Entity (MME), Serving-Gateway (S-GW), etc., but not limited thereto), or a combination thereof.

[0351] Each aspect / embodiment described in the present disclosure may be used alone, in combination, or switched and used during execution. Also, the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in the present disclosure may be rearranged as long as there is no contradiction. For example, for the method described in the present disclosure, the elements of various steps are presented using an exemplary order and are not limited to the specific order presented.

[0352] Each aspect / embodiment described in the present disclosure may be applied to systems using 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 (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 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), other suitable wireless communication methods, and next-generation systems extended, modified, created, or defined based on these. Also, a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G) may be applied.

[0353] As used in the present disclosure, the description "based on" does not mean "based only on" unless otherwise specified. In other words, the description "based on" means both "based only on" and "based at least on".

[0354] Any reference to an element using terms such as "first", "second", etc. used in this disclosure does not generally limit the quantity or order of those elements. These terms can be used in this disclosure as a convenient way to distinguish between two or more elements. Thus, a reference to a first and a second element does not mean that only two elements can be employed or that the first element must precede the second element in any way.

[0355] The term "determining" as used in this disclosure may encompass a wide variety of operations. For example, "determining" may be considered to be "judging", "calculating", "computing", "processing", "deriving", "investigating", "looking up, search, inquiry" (e.g., searching in a table, database or another data structure), "ascertaining", etc.

[0356] Also, "determining" may be considered to be "receiving" (e.g., receiving information), "transmitting" (e.g., transmitting information), "input", "output", "accessing" (e.g., accessing data in a memory), etc.

[0357] Also, "determining" may be considered to be "resolving", "selecting", "choosing", "establishing", "comparing", etc. That is, "determining" may be considered to be "determining" any operation.

[0358] Also, "determine (decide)" may be read as "assume", "expect", "consider", etc.

[0359] The "maximum transmit power" described in the present disclosure may mean the maximum value of the transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0360] As used in this disclosure, the terms "connected" and "coupled", or any variations thereof, mean any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "accessed".

[0361] In the present disclosure, when two elements are connected, they can be considered to be "connected" or "coupled" to each other using one or more electric wires, cables, printed electrical connections, etc., and also, by way of some non-limiting and non-exhaustive examples, electromagnetic energy having wavelengths in the radio frequency region, microwave region, optical (both visible and invisible) region, etc.

[0362] In the present disclosure, the term "A and B are different" may mean that "A and B are different from each other". Note that the term may also mean that "A and B are each different from C". Terms such as "separate" and "coupled" may also be interpreted in the same way as "different".

[0363] In the present disclosure, when the terms "include", "including" and their variants are used, these terms are intended to be inclusive in the same manner as the term "comprising". Further, the term "or" used in the present disclosure is intended not to be an exclusive disjunction.

[0364] In the present disclosure, for example, when articles are added by translation, such as a, an and the in English, the present disclosure may include that the nouns following these articles are in the plural form.

[0365] As described above, the invention according to the present disclosure has been described in detail. However, it is obvious 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 as modifications and variations without departing from the spirit and scope of the invention determined based on the description of the claims. Therefore, the description of the present disclosure is for illustrative purposes and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. A receiving unit that receives a setting indicating one set of beam failure detection reference signals (BFD-RS); a control unit that determines that two BFD-RS included in the BFD-RS set are demodulation reference signals (DM-RS) of one control resource set (CORESET) associated with two transmission configuration indication (TCI) states and are quasi-co-location (QCL); and a terminal in which the control unit evaluates one radio link quality for the CORESET based on the two TCI states.

2. A step of receiving a setting indicating one set of beam failure detection reference signals (BFD-RS); a step of determining that two BFD-RS included in the BFD-RS set are demodulation reference signals (DM-RS) of one control resource set (CORESET) associated with two transmission configuration indication (TCI) states and are quasi-co-location (QCL); and a step of evaluating one radio link quality for the CORESET based on the two TCI states, a radio communication method of a terminal.

3. A transmitting unit that transmits a setting indicating one set of beam failure detection reference signals (BFD-RS); a control unit that determines that two BFD-RS included in the BFD-RS set are demodulation reference signals (DM-RS) of one control resource set (CORESET) associated with two transmission configuration indication (TCI) states and are quasi-co-location (QCL); and a base station in which the control unit determines that one radio link quality for the CORESET is evaluated based on the two TCI states.

4. A system having a terminal and a base station, wherein the terminal has a receiving unit that receives a setting indicating one set of beam failure detection reference signals (BFD-RS), a control unit that determines that two BFD-RS included in the BFD-RS set are demodulation reference signals (DM-RS) of one control resource set (CORESET) associated with two transmission configuration indication (TCI) states and are quasi-co-location (QCL), the control unit evaluates one radio link quality for the CORESET based on the two TCI states, and the base station has a transmitting unit that transmits the setting.

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