Terminal, wireless communication method, base station and system

Abstract

This terminal according to one aspect of the present disclosure is characterized by having: a receiving unit for receiving information indicating one or more states from among a first Transmission Configuration Indication (TCI) state which is common to both downlink (DL) and uplink (UL), a second TCI state common to DL, and a third TCI state common to UL which are associated with another cell which has a physical cell ID which differs from the physical cell ID of the serving cell; and a control unit for applying one or more states from among the first TCI state, the second TCI state and the third TCI state which are indicated by said information to a specific channel in the other cell. According to this one aspect of the present disclosure, it is possible to appropriately transmit to or receive from another cell which has a physical cell ID which differs from the physical cell ID of the serving cell.

Description

[Technical Field]

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

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

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

[0004] [Non-Patent Document 1] 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010 Summary of the Invention [Problem to be solved by the invention]

[0005] In future wireless communication systems, layer 1 / layer 2 (L1 / L2) inter-cell mobility is being considered to facilitate more efficient (lower latency and overhead) DL / UL beam management.

[0006] However, when inter-cell mobility is applied, including other cells (non-serving cells) having physical cell IDs different from the physical cell ID of the serving cell, the processing for transmitting and receiving with other cells is not clear. As a result, transmission and reception with other cells cannot be performed appropriately, and there is a risk of a decrease in throughput or degradation of communication quality.

[0007] Therefore, the present disclosure provides a terminal and a wireless communication method that can appropriately transmit and receive data to and from other cells that have physical cell IDs different from the physical cell ID of the serving cell. 、 base station and systems One of the aims is to provide [Means for solving the problem]

[0008] A terminal according to one aspect of the present disclosure includes: a target cell ID represented by fewer bits than the number of bits used for the physical cell ID; Has a physical cell ID that is different from the physical cell ID of the serving cell The target associated with the cell, both downlink (DL) and uplink (UL) Applies First Transmission Configuration Indication state (TC I state) , DL Applies Second TCI condition, UL Applies Information indicating at least one third TCI state and a Medium Access Control Element (MAC CE) for serving cell change indication, including: a receiving unit for receiving the information, and a receiving unit for receiving at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information, target and a control unit for applying a particular channel to a cell. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, transmission and reception with other cells having physical cell IDs different from the physical cell ID of the serving cell can be performed appropriately. [Brief explanation of the drawings]

[0010] [Figure 1] 1A and 1B are diagrams showing an example of a common beam. [Figure 2] Figure 2A shows an example of inter-cell mobility involving a non-serving cell, and Figure 2B shows an example of a multi-TRP scenario. [Figure 3] 3A and 3B are diagrams illustrating a first example of a MAC CE. [Figure 4] 4A and 4B are diagrams illustrating a second example of a MAC CE. [Figure 5] FIG. 5 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. [Figure 6] FIG. 6 is a diagram illustrating an example of the configuration of a base station according to an embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. [Figure 8] FIG. 8 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (CSI report) In NR, a UE measures a channel state using a predetermined reference signal (or a resource for the reference signal) and feeds back (reports) channel state information (CSI) to a base station.

[0012] The UE may measure the channel state using a Channel State Information-Reference Signal (CSI-RS), a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block, a Synchronization Signal (SS), a Demodulation Reference Signal (DMRS), etc.

[0013] The CSI-RS resources may include at least one of a non-zero power (NZP) CSI-RS and a CSI-Interference Management (IM). An SS / PBCH block is a block including a synchronization signal (e.g., a primary synchronization signal (PSS) or a secondary synchronization signal (SSS)) and a PBCH (and corresponding DMRS), and may be referred to as an SS block (SSB). An SSB index may be assigned to the time position of the SSB within a half-frame.

[0014] The CSI may include at least one of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), a SS / PBCH block resource indicator (SS / PBCH block indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), a Layer 1 (L1)-Reference Signal Received Power (RSRP), a L1-Reference Signal Received Quality (RSRQ), a L1-Signal to Interference plus Noise Ratio (SINR), a L1-Signal to Noise Ratio (SNR), and the like.

[0015] The CSI may have multiple parts. The first part of the CSI (CSI Part 1) may include information with a relatively small number of bits (e.g., RI). The second part of the CSI (CSI Part 2) may include information with a relatively large number of bits (e.g., CQI), such as information determined based on CSI Part 1.

[0016] Methods of CSI feedback under consideration include (1) periodic CSI (P-CSI) reporting, (2) aperiodic CSI (A(AP)-CSI) reporting, and (3) semi-persistent CSI (SP-CSI) reporting.

[0017] The UE may be notified of information related to CSI reporting (which may be referred to as CSI reporting configuration information) using higher layer signaling, physical layer signaling (e.g., Downlink Control Information (DCI)), or a combination thereof. The CSI reporting configuration information may be configured using, for example, the RRC information element "CSI-ReportConfig."

[0018] Here, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

[0019] The MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (MAC PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0020] The CSI reporting configuration information may include, for example, information regarding a reporting period, an offset, etc., which may be expressed in a predetermined time unit (e.g., slot unit, subframe unit, symbol unit, etc.). The CSI reporting configuration information may include a configuration ID (CSI-ReportConfigId). The configuration ID may identify parameters such as the type of CSI reporting method (e.g., whether it is SP-CSI or not), the reporting period, etc. The CSI reporting configuration information may include information (CSI-ResourceConfigId) indicating which signal (or which signal resource) is used to report the measured CSI.

[0021] (Beam Management) Up until now, Rel-15 NR has been studying beam management (BM) methods. In this beam management, beam selection is being considered based on the L1-RSRP reported by the UE. Changing (switching) the beam of a certain signal / channel may be equivalent to changing the Transmission Configuration Indication state (TCI state) of the signal / channel.

[0022] The beam selected by beam selection may be a transmission beam (Tx beam) or a reception beam (Rx beam). Also, the beam selected by beam selection may be a beam of the UE or a beam of the base station.

[0023] The UE may report (transmit) measurement results for beam management using the PUCCH or PUSCH. The measurement results may be CSI including at least one of L1-RSRP, L1-RSRQ, L1-SINR, L1-SNR, etc. The measurement results may also be called beam measurements, beam measurement results, beam reports, beam measurement reports, etc.

[0024] The CSI measurement for the beam report may include interference measurement. The UE may measure channel quality, interference, etc. using resources for CSI measurement and derive a beam report. The resources for CSI measurement may be, for example, at least one of resources of SS / PBCH blocks, resources of CSI-RS, other reference signal resources, etc. Configuration information for CSI measurement reporting may be configured in the UE using higher layer signaling.

[0025] The beam report may include at least one of channel quality measurement and interference measurement results. The channel quality measurement results may include, for example, L1-RSRP. The interference measurement results may include L1-SINR, L1-SNR, L1-RSRQ, or other interference-related metrics (e.g., any metrics other than L1-RSRP).

[0026] Note that resources for CSI measurement for beam management may be referred to as beam measurement resources. Furthermore, signals / channels for which the CSI is measured may be referred to as beam measurement signals. Furthermore, CSI measurement / reporting may be interpreted as at least one of measurement / reporting for beam management, beam measurement / reporting, radio link quality measurement / reporting, etc.

[0027] The CSI reporting configuration information that takes into account current NR beam management is included in the RRC information element "CSI-ReportConfig." The information in the RRC information element "CSI-ReportConfig" is explained below.

[0028] The CSI reporting configuration information (CSI-ReportConfig) may include reporting quantity information ("report quantity", which may be expressed as the RRC parameter "reportQuantity"), which is information on parameters to be reported. The reporting quantity information is defined as an ASN.1 object type called "choice type". Therefore, one of the parameters (cri-RSRP, ssb-Index-RSRP, etc.) defined as the reporting quantity information is set.

[0029] A UE that has an upper layer parameter (e.g., the RRC parameter "groupBasedBeamReporting") included in the CSI reporting configuration information enabled may include multiple beam measurement resource IDs (e.g., SSBRI, CRI) and multiple corresponding measurement results (e.g., L1-RSRP) in the beam report for each reporting configuration.

[0030] A UE that has one or more numbers of RS resources to report configured by higher layer parameters included in the CSI reporting configuration information (e.g., the RRC parameter "nrofReportedRS") may include one or more beam measurement resource IDs and one or more corresponding measurement results (e.g., L1-RSRP) for each reporting configuration in the beam report.

[0031] (TCI, spatial relations, QCL) In NR, it is being considered to control the reception processing (e.g., at least one of reception, demapping, demodulation, and decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, and encoding) in the UE of at least one of a signal and a channel (referred to as signal / channel) based on the transmission configuration indication state (TCI state).

[0032] The TCI state may represent that which is applied to a downlink signal / channel, and the equivalent of the TCI state which is applied to an uplink signal / channel may be expressed as a spatial relation.

[0033] The TCI state is information about the quasi-co-location (QCL) of signals / channels, and may also be called spatial reception parameters, spatial relation information, etc. The TCI state may be configured in the UE for each channel or signal.

[0034] A QCL is an index that indicates the statistical properties of a signal / channel. For example, if a signal / channel has a QCL relationship with another signal / channel, it may mean that it can be assumed that at least one of the Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same between these different signals / channels (i.e., they are QCLs with respect to at least one of these).

[0035] The spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be determined based on a spatial QCL. A QCL (or at least one element of a QCL) in the present disclosure may be replaced with an sQCL (spatial QCL).

[0036] A plurality of types (QCL types) of QCLs may be defined. For example, four QCL types A and B may be provided, each having different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may also be referred to as QCL parameters) are listed below: QCL Type A (QCL-A): Doppler shift, Doppler spread, mean delay and delay spread, QCL Type B (QCL-B): Doppler shift and Doppler spread, QCL Type C (QCL-C): Doppler shift and mean delay, · QCL Type D (QCL-D): Spatial reception parameters.

[0037] The assumption by a UE that a given Control Resource Set (CORESET), channel, or reference signal is in a specific QCL (e.g., QCL type D) relationship with another CORESET, channel, or reference signal may be referred to as a QCL assumption.

[0038] The UE may determine at least one of a transmit beam (Tx beam) and a receive beam (Rx beam) for a signal / channel based on the TCI condition or QCL assumption of the signal / channel.

[0039] The TCI state may be, for example, information about the QCL between the target channel (in other words, the Reference Signal (RS) for the channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by higher layer signaling, physical layer signaling, or a combination thereof.

[0040] The channel for which the TCI state or spatial relationship is set (specified) may be, for example, at least one of a downlink shared channel (Physical Downlink Shared Channel (PDSCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), and an uplink control channel (Physical Uplink Control Channel (PUCCH)).

[0041] Furthermore, the RS that has a QCL relationship with the channel may be, for example, at least one of a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), a CSI-RS for tracking (also called a Tracking Reference Signal (TRS)), and a QCL detection reference signal (also called a QRS).

[0042] An SSB is a signal block that includes at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). An SSB may also be referred to as an SS / PBCH block.

[0043] A TCI state information element ("TCI-state IE" in RRC) configured by higher layer signaling may include one or more pieces of QCL information ("QCL-Info"). The QCL information may include at least one of information about an RS having a QCL relationship (RS relationship information) and information indicating a QCL type (QCL type information). The RS relationship information may include information such as an index of the RS (e.g., an SSB index, a Non-Zero-Power (NZP) CSI-RS resource identifier), an index of a cell in which the RS is located, and an index of a Bandwidth Part (BWP) in which the RS is located.

[0044] In Rel. 15 NR, both QCL type A RS and QCL type D RS, or only QCL type A RS, can be configured for a UE as the TCI state of at least one of the PDCCH and PDSCH.

[0045] When a TRS is configured as an RS for QCL Type A, unlike a demodulation reference signal (DMRS) for a PDCCH or a PDSCH, the same TRS is expected to be transmitted periodically over a long period of time. The UE can measure the TRS and calculate the average delay, delay spread, etc.

[0046] A UE that has the TRS configured as a QCL Type A RS in the TCI state of a PDCCH or PDSCH DMRS can assume that the QCL Type A parameters (average delay, delay spread, etc.) of the PDCCH or PDSCH DMRS and the TRS are the same, and can therefore determine the Type A parameters (average delay, delay spread, etc.) of the PDCCH or PDSCH DMRS from the measurement result of the TRS. When performing channel estimation for at least one of the PDCCH and the PDSCH, the UE can perform more accurate channel estimation using the measurement result of the TRS.

[0047] A UE configured with a QCL type D RS can determine a UE receive beam (spatial domain receive filter, UE spatial domain receive filter) using the QCL type D RS.

[0048] An RS of QCL type X in a TCI state may refer to an RS that has a relationship of QCL type X with (the DMRS of) a certain channel / signal, and this RS may be called a QCL source of QCL type X in the TCI state.

[0049] (Unified / Common TCI Framework) The unified TCI framework allows UL and DL channels to be controlled by a common framework. Instead of specifying TCI states or spatial relationships for each channel as in Rel. 15, the unified TCI framework may specify a common TCI state (common beam) and apply it to all UL and DL channels, or may apply a common TCI state for UL to all UL channels and a common TCI state for DL ​​to all DL channels.

[0050] One common TCI state for both DL and UL, or one common TCI state for DL ​​and one common TCI state for UL (two common TCI states in total) are considered.

[0051] The UE may assume the same TCI state for UL and DL (joint TCI state, joint TCI pool, joint common TCI pool, joint TCI state set). The UE may assume different TCI states for UL and DL (separate TCI state, separate TCI pool, UL separate TCI pool and DL separate TCI pool, separate common TCI pool, UL common TCI pool and DL common TCI pool).

[0052] The default beams for UL and DL may be aligned via MAC CE based beam management (MAC CE level beam direction). The default TCI state of the PDSCH may be updated to align with the default UL beam (spatial relationship).

[0053] DCI-based beam management (DCI-level beam indication) may indicate a common beam / unified TCI state from the same TCI pool (joint common TCI pool, joint TCI pool, set) for both UL and DL. X (>1) TCI states may be activated by the MAC CE. The UL / DL DCI may select one from the X active TCI states. The selected TCI state may apply to both UL and DL channels / RS.

[0054] The TCI pool (set) may be multiple TCI states configured by RRC parameters, or multiple TCI states (active TCI states, active TCI pools, sets) activated by the MAC CE among the multiple TCI states configured by RRC parameters. Each TCI state may be a QCL type A / D RS. SSB, CSI-RS, or SRS may be configured as the QCL type A / D RS.

[0055] The number of TCI states corresponding to each of one or more TRPs may be specified. For example, the number N (≧1) of TCI states applied to UL channels / RSs (UL TCI states) and the number M (≧1) of TCI states applied to DL channels / RSs (DL TCI states) may be specified. At least one of N and M may be notified / configured / instructed to the UE via higher layer signaling / physical layer signaling.

[0056] In the present disclosure, when N=M=X (X is any integer), it may mean that X TCI states (joint TCI states) common to UL and DL (corresponding to X TRPs) are notified / configured / instructed to the UE. Also, when N=X (X is any integer) and M=Y (Y may be any integer, Y=X), it may mean that X UL TCI states (corresponding to X TRPs) and Y DL TCI states (i.e., separate TCI states) (corresponding to Y TRPs) are notified / configured / instructed to the UE.

[0057] For example, when N=M=1 is written, this may mean that a TCI state common to one UL and DL for a single TRP is notified / configured / indicated to the UE (joint TCI state for a single TRP).

[0058] Also, for example, when N=1 and M=1, it may mean that one UL TCI state and one DL TCI state for a single TRP are separately notified / configured / instructed to the UE (separate TCI states for a single TRP).

[0059] Also, for example, when N=M=2 is written, this may mean that a TCI state common to multiple (two) ULs and DLs for multiple (two) TRPs is notified / configured / instructed to the UE (joint TCI state for multiple TRPs).

[0060] Also, for example, when N=2 and M=2, this may mean that the UE is notified / configured / instructed to have multiple (two) UL TCI states and multiple (two) DL TCI states for multiple (two) TRPs (separate TCI states for multiple TRPs).

[0061] In the above example, the case where the values ​​of N and M are 1 or 2 has been described, but the values ​​of N and M may be 3 or more, and N and M may be different.

[0062] In the example of Figure 1A, RRC parameters (information elements) configure multiple TCI states for both DL and UL. The MAC CE may activate multiple TCI states from the configured multiple TCI states. The DCI may indicate one of the activated multiple TCI states. The DCI may be a UL / DL DCI. The indicated TCI state may apply to at least one (or all) of the UL / DL channels / RS. One DCI may indicate both UL TCI and DL TCI.

[0063] In the example of FIG. 1A, a point may be one TCI state that applies to both the UL and DL, or two TCI states that apply to the UL and DL, respectively.

[0064] At least one of the multiple TCI states configured by the RRC parameters and the multiple TCI states activated by the MAC CE may be referred to as a TCI pool (common TCI pool, joint TCI pool, TCI state pool). The multiple TCI states activated by the MAC CE may be referred to as an active TCI pool (active common TCI pool).

[0065] In the present disclosure, higher layer parameters (RRC parameters) for setting multiple TCI states may be referred to as configuration information for setting multiple TCI states, or simply as "configuration information." Also, in the present disclosure, being instructed to set one of multiple TCI states using DCI may mean receiving indication information instructing one of the multiple TCI states included in DCI, or simply receiving "instruction information."

[0066] In the example of Figure 1B, the RRC parameters configure multiple TCI states (joint common TCI pools) for both DL and UL. The MAC CE may activate multiple TCI states (active TCI pools) from the configured multiple TCI states. Separate active TCI pools for UL and DL may be configured / activated.

[0067] The DL DCI or a new DCI format may select (indicate) one or more (e.g., one) TCI states. The selected TCI state may be applied to one or more (or all) DL channels / RSs. The DL channels may be PDCCH / PDSCH / CSI-RS. The UE may determine the TCI state of each DL channel / RS using the TCI state behavior (TCI framework) of Rel. 16. The UL DCI or a new DCI format may select (indicate) one or more (e.g., one) TCI states. The selected TCI state may be applied to one or more (or all) UL channels / RSs. The UL channels may be PUSCH / SRS / PUCCH. In this way, different DCIs may indicate the UL TCI and the DL DCI separately.

[0068] The existing DCI formats 1_1 / 1_2 may be used to indicate the common TCI status.

[0069] The common TCI framework may have separate TCI states for DL ​​and UL.

[0070] (Multi-TRP) It is being considered that one or more cells / transmission / reception points (TRPs) (multi-TRPs (MTRPs)) perform DL transmission to a UE. It is also being considered that a UE performs UL transmission to one or more cells / TRPs. As a procedure in this case, the following Scenario 1 or Scenario 2 can be considered. Note that in this disclosure, the serving cell may be read as a TRP in the serving cell. L1 / L2 signaling and MAC CE / DCI may be read as interchangeable. In this disclosure, a Physical Cell Identity (PCI) different from the PCI of the current serving cell may be simply referred to as a "different PCI." In Scenario 1, for example, the following procedure is performed.

[0071] <Scenario 1> (1) The UE receives from the serving cell the configuration necessary to use radio resources for data transmission and reception, including SSB configuration for beam measurement of a TRP having a PCI different from that of the serving cell, and resources of a different PCI. (2) The UE performs beam measurement of TRPs with different PCIs and reports the beam measurement results to the serving cell. (3) Based on the above report, the TCI states associated with the TRPs with different PCIs are activated by L1 / L2 signaling from the serving cell. (4) The UE transmits and receives using a UE dedicated channel on a TRP with a different PCI. (5) The UE must always cover the serving cell, including in the case of multiple TRPs. As in conventional systems, the UE must use common channels from the serving cell, such as the Broadcast Control Channel (BCCH) and the Paging Channel (PCH).

[0072] In Scenario 1, when a UE transmits and receives signals to and from a non-serving cell / TRP (a TRP having the PCI of the non-serving cell), the assumption of the "serving cell" is not changed. The UE is configured with higher layer parameters related to the PCI of the non-serving cell from the serving cell. Scenario 1 may be applied, for example, in Rel. 17.

[0073] <Scenario 2> In scenario 2, L1 / L2 inter-cell mobility is applied. With L1 / L2 inter-cell mobility, the serving cell can be changed using functions such as beam control without RRC reconfiguration. In other words, transmission and reception with a non-serving cell is possible without handover. Since handover requires RRC reconnection and creates a period when data communication is unavailable, by applying L1 / L2 inter-cell mobility that does not require handover, data communication can be continued even when the serving cell is changed. Scenario 2 may be applied in, for example, Rel. 18. In scenario 2, for example, the following procedure is performed.

[0074] (1) The UE receives from the serving cell the SSB configuration of a cell (non-serving cell) with a different PCI for beam measurement / serving cell change. (2) The UE performs beam measurements of cells using different PCIs and reports the measurement results to the serving cell. (3) The UE may receive a configuration of a cell with a different PCI (serving cell configuration) through higher layer signaling (e.g., RRC). That is, a pre-configuration regarding a serving cell change may be performed. This configuration may be performed together with the configuration in (1) or separately. (4) Based on the above report, the TCI states of cells with different PCIs may be activated by L1 / L2 signaling according to the change of serving cell. The activation of the TCI states and the change of serving cell may be performed separately. (5) The UE changes the serving cell and starts receiving / transmitting using the pre-configured UE-specific channel and TCI state.

[0075] That is, in scenario 2, the serving cell assumption is updated by L1 / L2 signaling.

[0076] An example in which a UE receives channels / signals from multiple cells / TRPs during inter-cell mobility will be described with reference to FIGS. 2A and 2B.

[0077] Figure 2A illustrates an example of inter-cell mobility involving a non-serving cell (e.g., single-TRP inter-cell mobility). Single-TRP may refer to a case where only one TRP transmits to the UE (also referred to as single mode). Here, the UE receives channels / signals from the base station / TRP of cell #1 (PCI #1), which is the serving cell, and the base station / TRP of cell #3 (PCI #3), which is the non-serving cell.

[0078] For example, if the serving cell of the UE switches (e.g., fast cell switch) from cell #1 to cell #3, the DCI / MAC CE may update the TCI state and dynamically select a port (e.g., antenna port) / TRP / point.

[0079] Figure 2B shows an example of a multi-TRP scenario (e.g., multi-TRP inter-cell mobility) where a UE receives channels / signals from TRP#1 and TRP#2. Here, TRP#1 is in cell#1 (PCI#1) and TRP#2 is in cell#2 (PCI#2).

[0080] The multi-TRPs (TRP#1, #2) may be connected via an ideal / non-ideal backhaul, and information, data, etc. may be exchanged. Each TRP of the multi-TRP may transmit a different code word (CW) and a different layer. Non-Coherent Joint Transmission (NCJT) may be used as a form of multi-TRP transmission. In FIG. 2B, NCJT may be performed between multiple cells (cells with different PCIs). Note that the same serving cell configuration may be applied / configured to TRP#1 and TRP#2.

[0081] In the NCJT, for example, TRP#1 performs modulation mapping and layer mapping on a first codeword to transmit a first signal / channel (e.g., PDSCH) using a first number of layers (e.g., two layers) with a first precoding, and TRP#2 performs modulation mapping and layer mapping on a second codeword to transmit a second number of layers (e.g., two layers) with a second precoding to transmit a second signal / channel (e.g., PDSCH).

[0082] The multiple PDSCHs (multi-PDSCHs) that are non-coherent may be defined as partially or completely overlapping in time and / or frequency domains, i.e., the first PDSCH from TRP#1 and the second PDSCH from TRP#2 may overlap in time and / or frequency resources.

[0083] The first PDSCH and the second PDSCH may be assumed to be not quasi-co-located (Quasi-Co-Location (QCL)). Reception of multiple PDSCHs may be interpreted as simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

[0084] Multiple PDSCHs from multiple TRPs (which may also be referred to as multiple PDSCHs) may be scheduled using one DCI (single DCI (S-DCI), single PDCCH) (single master mode). One DCI may be transmitted from one TRP of the multiple TRPs. The configuration using one DCI in multiple TRPs may also be referred to as single DCI-based multiple TRPs (mTRP / MTRP).

[0085] A case may also be applied in which each of the multi-TRPs transmits a part of the control signal to the UE and the multi-TRP transmits the data signal (which may be called a master-slave mode).

[0086] Multiple PDSCHs from multiple TRPs may be scheduled using multiple DCIs (multiple DCI (M-DCI), multiple PDCCHs (multiple PDCCHs)), respectively (multiple master mode). Multiple DCIs may be transmitted from multiple TRPs, respectively. A configuration using multiple DCIs in multiple TRPs may be called a multi-DCI-based multi-TRP (mTRP / MTRP).

[0087] It may be assumed that the UE transmits separate CSI reports (CSI reports) for different TRPs. Such CSI feedback may be referred to as separate feedback, separate CSI feedback, etc. In this disclosure, "separate" may be interchangeably read as "independent."

[0088] (Problem) When inter-cell mobility is applied, including other cells (non-serving cells) having physical cell IDs different from the physical cell ID of the serving cell, the process for transmitting and receiving data with the other cells is not clear. This may result in inappropriate transmission and reception with the other cells, resulting in a decrease in throughput or degradation of communication quality. For example, the following problems may occur:

[0089] <Problem 1> In L1 / L2 inter-cell mobility, beam indication is considered to be based on a unified (common) TCI framework. However, when a common TCI state associated with cells of different PCIs is indicated by MAC CE and / or DCI, it is unclear to which channels the common TCI state (beam) can be applied. For example, it is unclear whether the common TCI state can be applied to PDSCH / PUSCH associated with a UE-specific CORESET, UE-specific PDCCH / PUCCH, several group-common PDCCHs, semi-persistent scheduling (SPS) PDSCH / Cell Group (CG) PUSCH, etc.

[0090] <Problem 2> For example, in Rel. 17, there is no change of serving cell (Scenario 1), and in Rel. 18, the change of serving cell is expected to be supported by L1 / L2 inter-cell mobility. However, the detailed design (signaling design, etc.) for supporting the change of serving cell has not been clarified.

[0091] <Problem 3> It is not clear what the UE should do after receiving a serving cell change indication due to L1 / L2 inter-cell mobility.

[0092] Therefore, the present inventors came up with the idea of ​​a terminal that can appropriately transmit and receive data to and from other cells.

[0093] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0094] In the present disclosure, "A / B / C" and "at least one of A, B, and C" may be read as interchangeable. In the present disclosure, cell, serving cell, CC, carrier, BWP, DL BWP, UL BWP, active DL BWP, active UL BWP, and band may be read as interchangeable. In the present disclosure, index, ID, indicator, and resource ID may be read as interchangeable. In the present disclosure, support, control, controllable, operate, and operable may be read as interchangeable.

[0095] In the present disclosure, the terms configure, activate, update, indicate, enable, specify, and select may be read interchangeably.

[0096] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof. In the present disclosure, RRC, RRC signaling, RRC parameters, higher layer, higher layer parameters, RRC information elements (IEs), and RRC messages may be interchangeable.

[0097] The MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0098] The physical layer signaling may be, for example, Downlink Control Information (DCI).

[0099] In the present disclosure, MAC CE and activation / deactivation command may be read interchangeably.

[0100] In the present disclosure, the terms pool, set, group, list, and candidate may be read interchangeably.

[0101] In the present disclosure, the terms DMRS, DMRS port, and antenna port may be interpreted as interchangeable.

[0102] In this disclosure, the terms beam, spatial-domain filter, spatial setting, TCI state, UL TCI state, unified TCI state, unified beam, common TCI state, common beam, TCI assumption, QCL assumption, QCL parameter, spatial-domain receive filter, UE spatial-domain receive filter, UE receive beam, DL beam, DL receive beam, DL precoding, DL precoder, DL-RS, RS for QCL type D in TCI state / QCL assumption, RS for QCL type A in TCI state / QCL assumption, spatial relationship, spatial-domain transmit filter, UE spatial-domain transmit filter, UE transmit beam, UL beam, UL transmit beam, UL precoding, UL precoder, and PL-RS may be interchangeable. In this disclosure, the terms QCL type X-RS, DL-RS associated with QCL type X, DL-RS with QCL type X, source of DL-RS, SSB, CSI-RS, and SRS may be interchangeable.

[0103] In the present disclosure, the terms common beam, common TCI, common TCI state, unified TCI, unified TCI state, TCI state applicable to DL and UL, TCI state applicable to multiple (multiple types) channels / RS, TCI state applicable to multiple types of channels / RS, and PL-RS may be interchangeable. Common, unified, and joint may be interchangeable.

[0104] In the present disclosure, the terms TCI state, multiple TCI states configured by RRC, multiple TCI states activated by MAC CE, pool, TCI state pool, active TCI state pool, common TCI state pool, joint TCI state pool, separate TCI state pool, common TCI state pool for UL, common TCI state pool for DL, common TCI state pool configured / activated by RRC / MAC CE, and TCI state information may be read interchangeably.

[0105] In the present disclosure, the terms panel, Uplink (UL) transmitting entity, TRP, spatial relationship, control resource set (CORESET), PDSCH, codeword, base station, antenna port of a certain signal (e.g., Demodulation Reference Signal (DMRS) port), antenna port group of a certain signal (e.g., DMRS port group), group for multiplexing (e.g., Code Division Multiplexing (CDM) group, reference signal group, CORESET group), CORESET pool, CORESET subset, CW, redundancy version (RV), and layer (MIMO layer, transmission layer, spatial layer) may be interchangeable. Also, panel identifier (ID) and panel may be interchangeable. In the present disclosure, the terms TRP ID, TRP related ID, CORESET pool index, the position of one of two TCI states corresponding to one code point in a field in a DCI (ordinal number, first TCI state or second TCI state), and TRP may be read interchangeably.

[0106] In the present disclosure, the terms TRP, transmission point, panel, DMRS port group, CORESET pool, and one of two TCI states associated with one code point in a TCI field may be read interchangeably.

[0107] In the present disclosure, the following may be read interchangeably: single TRP, single DCI, single PDCCH, multi-TRP based on single DCI, single TRP system, single TRP transmission, single PDSCH, channel using single TRP, channel using one TCI state / spatial relationship, multi-TRP not being enabled by RRC / DCI, multiple TCI states / spatial relationships not being enabled by RRC / DCI, a CORESET pool index (CORESETPoolIndex) value of 1 not being set for any CORESET and no code point in the TCI field being mapped to two TCI states, and two TCI states on at least one TCI code point being activated.

[0108] In the present disclosure, the terms "multi-TRP," "multi-TRP system," "multi-TRP transmission," "multi-PDSCH," "channel using multi-TRP," "channel using multiple TCI states / spatial relationships," "multi-TRP being enabled by RRC / DCI," "multiple TCI states / spatial relationships being enabled by RRC / DCI," and "at least one of multi-TRP based on a single DCI" and "multi-TRP based on multiple DCI" may be interchangeable. In the present disclosure, the terms "multi-TRP based on multiple DCI," and "setting a CORESET pool index (CORESETPoolIndex) value of 1 for the CORESET" may be interchangeable. In the present disclosure, the terms "multi-TRP based on a single DCI," and "at least one code point in the TCI field is mapped to two TCI states" may be interchangeable.

[0109] In the present disclosure, TRP#1 (first TRP) may correspond to CORESET pool index=0 or may correspond to the first of two TCI states corresponding to one code point in the TCI field. TRP#2 (second TRP) may correspond to CORESET pool index=1 or may correspond to the second of two TCI states corresponding to one code point in the TCI field.

[0110] In the present disclosure, cell, serving cell, CC, BWP, BWP within a CC, and band may be read interchangeably.

[0111] In the present disclosure, other cells, non-serving cells, cells with different PCIs, candidate serving cells, cells with PCIs different from the PCI of the current serving cell, and other serving cells may be interchangeable. Dedicated and specific may be interchangeable.

[0112] (Wireless communication method) First Embodiment The serving cell receives information indicating a common TCI state associated with another cell having a physical cell ID (PCI) different from the PCI of the serving cell. The common TCI state may be a TCI state applicable to multiple types of channels / signals. The common TCI state may be at least one of a first TCI state common to both downlink (DL) and uplink (UL), a second TCI state common to DL, and a third TCI state common to UL. The first TCI state may be a TCI state applicable to multiple types of channels / signals in DL and UL (joint TCI state). The second TCI state may be a TCI state applicable to multiple types of channels / signals in DL (separate DL TCI state). The second TCI state may be a TCI state applicable to multiple types of channels / signals in UL (separate UL TCI state). The information indicating the first TCI state is, for example, an indication by MAC CE and DCI as shown in FIG. 1A. The information indicating the second TCI state and the third TCI state is, for example, an indication by the MAC CE and DCI shown in Fig. 1B. The UE applies at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information to a specific channel transmitted to / received from the other cell. This specific channel is at least one of CH1 to CH9 below.

[0113] CH1: CH1 may include the following CH1_DL / CH1_UL. CH1_DL: PDSCH scheduled by a UE-dedicated CORESET / UE-specific Search Space (USS) (PDSCH scheduled by a PDCCH detected in the CORESET / USS). CH1_UL: PUSCH scheduled by a UE-specific CORESET / USS (PUSCH scheduled by a PDCCH detected in the CORESET / USS). CH2: CH2 may include the following CH2_DL / CH2_UL. ·CH2_DL: UE-specific PDCCH. · CH2_UL: UE individual PUCCH. CH3: CH3 may include the following CH3_UL. · CH3_UL: Type 1 CG PUSCH configured by higher layer signaling (e.g. RRC). CH4: CH4 may include the following CH4_DL / CH4_UL. · CH4_DL: SPS PDSCH configured by higher layer signaling (e.g. RRC) and activated by DCI. · CH4_UL: Type 2 CG PUSCH configured by higher layer signaling (e.g. RRC) and activated by DCI. CH5: Type 0-PDCCH A PDCCH detected in the Common Search Space (CSS). CH6: Type 0A-PDCCH PDCCH detected in CSS. CH7: Type 1-PDCCH PDCCH detected in CSS. CH8: Type 2-PDCCH PDCCH detected in CSS. CH9: Type 3-PDCCH PDCCH detected in CSS.

[0114] [Aspect 1-1] When a joint DL / UL TCI state (a first TCI state common to both DL and UL) associated with a cell having a PCI different from the PCI of the serving cell is indicated by the MAC CE / DCI (see, for example, FIG. 1A), any of the following options 1-1 to 1-4 may be applied to the applicable channel of the TCI state. Note that the TCI state may be, for example, a common TCI state specified in Rel. 17. In the present disclosure, "A / B / C" and "at least one of A, B, and C" may be read as interchangeable. " / " may be read as "and" or "or."

[0115] [Option 1-1] CH1 only [Option 1-2] CH1 / CH2 [Option 1-3] CH1 / CH2 / CH3 / CH4 [Option 1-4] CH1 / CH2 / CH9

[0116] The channels to which the common TCI state (beam) can be applied are not limited to the above options (options 1-1, 1-2, 1-3, and 1-4). For example, a combination of two or more options, or a combination of a channel of each option with another channel may be applied. However, CH5, CH6, and CORESET#0 may not be permitted. CH7 and CH8 may or may not be permitted.

[0117] [Aspect 1-2] When separate DL / UL TCI states (at least one of a second TCI state common to DL and a third TCI state common to UL) associated with a cell having a PCI different from the PCI of the serving cell are indicated by the MAC CE / DCI (see, for example, FIG. 1B), any of the following options 1-5 to 1-8 may be applied to a channel to which the DL common TCI state (second TCI state) is applicable. Any of the following options 1-9 to 1-11 may be applied to a channel to which the UL common TCI state (third TCI state) is applicable.

[0118] [Option 1-5] CH1_DL only [Option 1-6] CH1_DL / CH2_DL [Option 1-7] CH1_DL / CH2_DL / CH4_DL [Option 1-8] CH1_DL / CH2_DL / CH9

[0119] The channels to which the above DL common TCI state can be applied are not limited to the above options (options 1-5 / 1-6 / 1-7 / 1-8), but may also be a combination of two or more options, or a combination of each option with other DL channels. CH5 / CH6 / CORESET#0 may not be permitted. CH7 / CH8 may or may not be permitted.

[0120] [Option 1-9] CH1_UL only [Option 1-10] CH1_UL / CH2_UL [Options 1-11] CH1_UL / CH2_UL / CH3_UL / CH4_UL

[0121] The channels to which the above UL common TCI state can be applied are not limited to the above options (options 1-9 / 1-10 / 1-11), and for example, a combination of two or more options, or a combination of each option with other UL channels may be applied.

[0122] According to this embodiment, it becomes clear to which channel a common TCI state associated with cells of different PCIs is applied, which means that the above problem 1 can be solved.

[0123] For example, if a UE can receive PDSCH from cells with different PCIs, it must monitor at least SIB / paging and Random Access Response (RAR) from the serving cell. This increases the processing load on the UE. However, by limiting the channels used for transmission and reception with cells with different PCIs, the processing load on the UE can be reduced.

[0124] <Second embodiment> In the second embodiment, implicit or explicit signaling for a serving cell change instruction will be described. As the TCI state of this embodiment, at least one of the first TCI state, the second TCI state, and the third TCI state (joint TCI state or separate TCI state) of the first embodiment may be applied.

[0125] [Aspect 2-1] In example 2-1, implicit signaling for a serving cell change instruction will be described. Example 2-1 is applied to, for example, the above-mentioned scenario 2.

[0126] [[Option 2-1]] When a specific control resource set (CORESET) (e.g., at least one of CORESET#0, CORESET of CH5 Type0-CSS, and CORESET of CH6 / CH7 / CH8 CSS) is indicated (activated) by the MAC CE together with one or more TCI states associated with cells of PCIs different from the PCI of the serving cell (when one or more TCI states associated with cells of PCIs different from the PCI of the serving cell are indicated / activated by the MAC CE for a specific CORESET), the UE may determine to change the serving cell to another cell (cell x, a cell with a different PCI). In other words, this activation may implicitly indicate that the serving cell will be changed to another cell.

[0127] In this case, the UE may update the beams of other CORESET IDs, other CORESETs using CH6 / CH7 / CH8, or other CORESETs using CSS to the same TCI state as the activated TCI state.

[0128] [[Option 2-2]] When a MAC CE activates / deactivates a TCI state of a PDSCH, if all such TCI states activated by the MAC CE are associated with the same cell x having a PCI different from that of the serving cell, the UE may determine to change the serving cell to another cell (cell x), i.e., this association may implicitly indicate that the serving cell is changed to another cell.

[0129] In the case where this option applies, if the NW (base station) does not change the serving cell, when the MAC CE activates the TCI state of a PDSCH associated with a cell with a different PCI, it must also include the TCI state related to another cell (e.g., the current serving cell or a cell with a second different PCI).

[0130] [[Option 2-3]] When a MAC CE activates / deactivates unified TCI states (e.g., corresponding to the unified TCI framework in Rel. 17) and all activated unified TCI states are associated with the same cell x with different PCIs, the UE may determine to change the serving cell to another cell (cell x). That is, this association may implicitly indicate that the serving cell will be changed to another cell.

[0131] [[Variations]] In Option 2-2 / 2-3, if some of the active TCI states are associated with Cell#1 / PCI#1 and other TCI states are associated with Cell#2 / PCI#2 (referred to as a modified case), at least one of the following (1) to (3) may be applied: For example, different TCI code points may indicate different cells / PCIs.

[0132] (1) The UE does not update (change) its serving cell assumption, but the UE can send and receive signals to and from non-serving cells / PCIs (i.e., corresponding to Scenario 1).

[0133] (2) A UE can be connected to multiple serving cells (a UE can assume multiple serving cells). A UE can transmit and receive signals to and from multiple serving cells / PCIs.

[0134] (3) When Scenario 2 is applied, the UE does not assume (expect) that different TCI codepoints are configured to indicate different cells / PCIs.

[0135] Note that this variant case may occur under the current single-cell configuration framework when different PCI cells share the same (or nearly the same) serving cell configuration. Therefore, the UE can dynamically switch between two cells for PDSCH reception, as in the mTRP configuration framework. Otherwise, the UE needs to simultaneously maintain multiple serving cell configurations. For example, when the UE receives a PDSCH from PCI#1, the UE uses the PDSCH configuration for PCI#1. When the UE receives a PDSCH from PCI#2, the UE uses the PDSCH configuration for PCI#2. The UE may maintain two user planes (U-planes) corresponding to the configurations.

[0136] Therefore, when cells with different PCIs share a serving cell configuration (or at least the same PDSCH configuration), the above variant case may occur (the UE may assume the above variant case). However, when the serving cell configurations (or at least individual PDSCH configurations) of cells with different PCIs are different, the UE may not assume the above variant case.

[0137] [Aspect 2-2] In example 2-2, explicit signaling for a serving cell change instruction will be described. Example 2-2 is applied to, for example, the above-mentioned scenario 2.

[0138] [[Option 2-3]] An example of a serving cell change instruction will be described below. Note that activation / deactivation of a non-serving cell, a change of the serving cell, and transmission / reception with another cell (non-serving cell) having a physical cell ID different from the physical cell ID of the serving cell may be interpreted as interchangeable.

[0139] The UE may receive a new MAC CE that includes at least one of the fields (information) indicating the following (1) to (3) corresponding to the non-serving cell, which is used for activating / deactivating the non-serving cell. When the UE receives the MAC CE, the UE may determine to change the serving cell to another cell (non-serving cell). The UE may also control transmission and reception of DL signals / UL signals with the non-serving cell based on the information. Note that the non-serving cell may be one or multiple. In the example shown below, a MAC CE that includes multiple fields indicating multiple non-serving cell indexes is applied.

[0140] (1) Serving Cell ID. (2) BWP ID. (3) Non-serving cell ID used for activation: The non-serving cell ID may be replaced with any information corresponding to the non-serving cell (that can identify the non-serving cell).

[0141] As an example of (3), any of (3-1) to (3-5) may be applied. (3-1) PCI (direct PCI). For example, 10 bits are used. (3-2) Regeneration index (new ID) of non-serving cells. The new ID is associated with a part of the PCI and may be set only to serving cells and non-serving cells used (available) by the UE. The new ID can reduce the number of bits compared to the PCI. (3-3) CSI reporting configuration ID (CSI-ReportConfigId) (if the CSI-ReportConfig corresponds to one or more non-serving cells). (3-4) CSI resource configuration ID (CSI-ResourceConfigId) (if CSI-ResourceConfigId corresponds to one or more non-serving cells). (3-5) A bitmap indicating the activation / deactivation of each non-serving cell. The size (number of bits) of the bitmap may be the same as the number of non-serving cells configured on this CC. For example, if the second non-serving cell of three non-serving cells is to be activated, "010" is set.

[0142] 3A and 3B are diagrams showing a first example of a MAC CE. In FIGS. 3A and 3B, it is assumed that there are seven non-serving cells. Each of FIGS. 3A and 3B includes the above fields (1) to (3). A non-serving cell ID (3-bit) may indicate one non-serving cell that is activated for L1 beam reporting. The number of bits of the non-serving cell ID does not have to be 3 bits and may vary depending on the number (maximum number) of non-serving cells.

[0143] The "P" field may indicate whether the next octet (entry) exists. The "P" field may indicate whether at least one of (1) to (3) exists in the MAC CE. FIG. 3A corresponds to one CC. FIG. 3B corresponds to multiple CCs, and each CC includes fields (1) to (3) and a "P" field.

[0144] Figures 4A and 4B are diagrams showing a second example of a MAC CE. Figures 4A and 4B differ from Figures 3A and 3B in that the non-serving cell ID (3-bit) is replaced with seven IDs (7-bit bitmap), but are otherwise similar. The seven IDs correspond to the above (3-5), and each of the seven IDs corresponds to a non-serving cell. The seven IDs may be expressed as T1, T2...T7. Figure 4A corresponds to one CC. Figure 4B corresponds to multiple CCs, and each CC includes fields (1) to (3) and a "P" field.

[0145] At least one of the pieces of information included in the MAC CE may be included in the DCI. Alternatively, at least one of the serving cells activated by the MAC CE may be indicated by the DCI. The MAC CE / DCI may include a field indicating the TCI status / SSB / CSI-RS from a cell with a different PCI so that the UE can recognize the DL beam to monitor on the target cell (post-change serving cell). The UE may create and transmit a beam report (CSI report) using the TCI status / SSB / CSI-RS.

[0146] For example, if separate DL / UL TCI states (see Figure 1B) are applied, the MAC CE / DCI may include additional fields indicating the target cell's UL beam / TCI state / spatial relationship / SSB / CSI-RS / SRS.

[0147] [[Options 2-4]] The UE may receive a MAC CE in which a new 1-bit field "C" is added to the existing MAC CE. The field indicates whether to change the serving cell. The UE may receive the MAC CE and determine whether to change the serving cell to another cell based on the field.

[0148] For example, at least one of the following fields may be added to an existing MAC CE: a field indicating activation / deactivation of the TCI state of a PDSCH, a field indicating activation / deactivation of a cell with a different PCI, a field indicating an RS (e.g., SSB) for beam measurement / reporting of a cell with a different PCI, and a field indicating other purposes / functions. In this case, the number of cells associated / indicated with a different PCI in the MAC CE may be only one cell.

[0149] Each field shown in this option may be applied in combination with either the existing MAC CE or the MAC CE of Figures 3A, 3B, 4A, and 4B.

[0150] [[Options 2-5]] For the MAC CE in Option 2-4, the MAC CE in Figures 3A, 3B, 4A, and 4B may further include fields indicating the serving cell index / PCI / other ID (such as the new ID in Option 2-3 above), and fields for the TCI status / SSB / CSI-RS of the target cell (the serving cell after the change).

[0151] For example, when separate DL / UL TCI states are applied (see Figure 1B), the MAC CEs in Figures 3A, 3B, 4A, and 4B may include additional fields for the target cell's UL beam / TCI state / spatial relationship / SSB / CSI-RS / SRS.

[0152] According to this embodiment, a detailed design for supporting a change of a serving cell becomes clear, and therefore the serving cell can be changed appropriately, which means that the above-mentioned problem 2 can be solved.

[0153] <Third embodiment> In this embodiment, the operation of a UE after detecting an implicit / explicit serving cell change instruction (see, for example, the second embodiment) will be described. As the TCI state of this embodiment, at least one of the first TCI state, the second TCI state, and the third TCI state (joint TCI state or separate TCI state) in the first embodiment may be applied.

[0154] The UE changes the serving cell configuration to the target cell configuration (another cell, a changed serving cell) based on the multi-cell configuration previously received by higher layer signaling (e.g., RRC). The configuration may be, for example, a CSI reporting configuration (CSI-ReportConfig), a CSI resource configuration (CSI-ResourceConfig), etc.

[0155] The UE flushes / clears the DL / UL configured resources of the previous serving cell and reconfigures the DL / UL configured resources of the target cell. The UE may keep the configuration of the previous serving cell in case a handover occurs (the serving cell returns to the previous serving cell).

[0156] The UE receives DL transmission from the target cell using the new beam / TCI state according to the target cell-related indication (e.g., TCI state (beam) / SSB / CSI-RS) by the MAC CE as shown in the second embodiment. In the absence of an indication regarding the target cell, the new beam / TCI state may correspond to the latest PRACH transmission associated with the SSB of the target cell.

[0157] The UE may receive only CORESET#0 and at least one of CH5, CH6, CH7, CH8, CH9, CH1_DL, CH2_DL, and CH4_DL as DLs received from the target cell.

[0158] If there are indications (TCI state (beam) / SSB / CSI-RS) regarding the target cell shown in the second embodiment, the UE transmits UL signals to the target cell using the new beam / TCI state / spatial relationship assumption according to those indications. If there is no indication of the TCI state (beam) or UL TCI state (beam) of the target cell in the second embodiment, the new beam / TCI state / spatial relationship may correspond to the latest PRACH transmission related to the SSB of the target cell.

[0159] The UE may transmit at least one of CH1_UL, CH2_UL, CH3_UL, and CH4_UL as an UL to be transmitted to the target cell. Note that the UE may change only the DL beam of the target cell without changing the UL beam of the target cell. The UL beam may be configured by RRC configuration signaling.

[0160] According to this embodiment, the operation of the UE after receiving a serving cell change instruction due to L1 / L2 inter-cell mobility becomes clear. That is, the above problem 3 is solved.

[0161] <UE capability> The UE may report (transmit) UE capability information indicating whether it supports at least one of each process in the present disclosure. For example, the UE may transmit at least one of the following UE capability information (1) to (3).

[0162] (1) Whether it supports a serving cell change instruction using MAC CE / DCI. (2) Whether it supports automatic DL beam (TCI state) update by the UE after L1 / L2 (using MAC CE / DCI) serving cell change. (3) Whether it supports automatic UL beam (TCI state) update by the UE after L1 / L2 (using MAC CE / DCI) serving cell change.

[0163] Also, the UE may receive information for instructing / setting at least one of each process in the present disclosure by DCI / MAC CE / higher layer signaling, etc. The information may correspond to the UE capability information transmitted by the UE.

[0164] (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.

[0165] 5 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0166] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0167] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0168] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and the SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0169] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0170] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

[0171] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may be a frequency band higher than FR2.

[0172] Furthermore, the user terminal 20 may perform communication using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

[0173] The multiple base stations 10 may be connected by wire (for example, optical fiber conforming to the Common Public Radio Interface (CPRI), an X2 interface, or the like) or wirelessly (for example, NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0174] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0175] The user terminal 20 may be a terminal compatible with at least one of communication methods such as LTE, LTE-A, and 5G.

[0176] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the radio communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0177] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0178] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0179] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

[0180] The PDSCH transmits user data, higher layer control information, System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit Master Information Block (MIB).

[0181] 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.

[0182] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as an UL grant, a UL DCI, etc. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

[0183] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources to search for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor a CORESET associated with a certain search space based on the search space configuration.

[0184] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be called a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in the present disclosure may be read interchangeably.

[0185] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), acknowledgement information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0186] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0187] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted as DL-RS.

[0188] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including the SS (PSS, SSS) and the PBCH (and DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as reference signals.

[0189] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0190] (base station) 6 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0191] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0192] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0193] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0194] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0195] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 1211 and an RF unit 122. The receiving unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0196] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0197] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0198] The transceiver 120 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0199] The transceiver 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0200] The transceiver 120 (transmission processor 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0201] The transmitting / receiving unit 120 (RF unit 122) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna .

[0202] On the other hand, the transmitting / receiving unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna .

[0203] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0204] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0205] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0206] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0207] In addition, the transceiver 120 may transmit information indicating at least one of a first Transmission Configuration Indication state (TCI) common to both downlink (DL) and uplink (UL), a second TCI state common to DL, and a third TCI state common to UL, which are associated with another cell having a physical cell ID different from the physical cell ID of the serving cell.

[0208] The control unit 110 may control at least one of transmission and reception of a specific channel for the other cell when at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information is applied to the specific channel for the other cell.

[0209] (user terminal) 7 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0210] Note that this example mainly shows functional blocks of the characteristic parts of the present embodiment, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0211] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0212] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 220.

[0213] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured from a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0214] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0215] The transmitting / receiving antenna 230 can be configured as an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0216] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0217] The transceiver 220 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0218] The transceiver 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0219] The transceiver 220 (transmission processor 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0220] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and when transform precoding is not enabled, the transceiver unit 220 may not perform DFT processing as the transmission processing.

[0221] The transmitting / receiving unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna 230.

[0222] On the other hand, the transmitting / receiving unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna 230.

[0223] The transceiver 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

[0224] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurement, CSI measurement, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0225] The transmitting section and receiving section of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving section 220 and the transmitting / receiving antenna 230.

[0226] In addition, the transceiver 220 may receive information indicating at least one of a first Transmission Configuration Indication state (TCI) common to both downlink (DL) and uplink (UL), a second TCI state common to DL, and a third TCI state common to UL, which are associated with another cell having a physical cell ID different from the physical cell ID of the serving cell.

[0227] The control unit 210 may apply at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information to a specific channel for the other cell.

[0228] The control unit 210 may determine to change the serving cell to the other cell when at least one of the first TCI state, the second TCI state, and the third TCI state is indicated for a specific control resource set.

[0229] The transceiver 220 may receive a Medium Access Control Element (MAC CE) including a field indicating whether to change the serving cell, and the controller 210 may determine whether to change the serving cell to the other cell based on the field.

[0230] The control unit 210 may change the configuration of the serving cell to the configuration of the other cell based on the configuration received by higher layer signaling.

[0231] (Hardware configuration) The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0232] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As mentioned above, the implementation method of each is not particularly limited.

[0233] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 8 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0234] In this disclosure, terms such as apparatus, circuit, device, section, unit, etc. may be read interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0235] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0236] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading predetermined software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0237] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transmission / reception unit 120 (220), etc. may be realized by the processor 1001.

[0238] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be realized in a similar manner.

[0239] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, a cache, a main memory, or the like. The memory 1002 may store executable programs (program codes), software modules, and the like for implementing a wireless communication method according to an embodiment of the present disclosure.

[0240] Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as a secondary storage device.

[0241] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0242] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0243] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0244] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using such hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0245] (Variation) Note that terms explained in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0246] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0247] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, a subcarrier spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a transmission time interval (TTI), the number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transceiver in the frequency domain, and a specific windowing process performed by a transceiver in the time domain.

[0248] A slot may be composed of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol), and may be a time unit based on numerology.

[0249] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0250] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0251] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0252] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0253] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0254] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0255] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0256] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0257] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0258] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0259] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0260] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0261] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0262] The BWP may include an UL BWP (a BWP for UL) and a DL BWP (a BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0263] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0264] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0265] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0266] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0267] 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.

[0268] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0269] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0270] Notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0271] Note that the physical layer signaling may be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be called an RRC message, such as an RRC connection setup message or an RRC connection reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0272] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0273] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0274] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0275] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0276] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0277] In the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0278] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0279] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0280] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0281] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0282] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0283] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, terms such as uplink channel and downlink channel may be read as sidelink channel.

[0284] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0285] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME) and a Serving-Gateway (S-GW)), or a combination thereof.

[0286] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the specific order presented.

[0287] Each aspect / embodiment described in the present disclosure may be related to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE The present invention may be applied to systems that use 802.20, Ultra-Wide Band (UWB), Bluetooth (registered trademark), or other appropriate wireless communication methods, or to next-generation systems that are based on and extend these systems. Furthermore, the present invention may be applied to a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0288] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0289] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0290] The term "determining," as used in this disclosure, may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0291] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0292] Also, "decision" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "decision" may be considered to be "deciding" on some action.

[0293] Furthermore, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," or the like.

[0294] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0295] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0296] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0297] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0298] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0299] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. A receiver that receives a Medium Access Control Control Element (MAC CE) for a serving cell change instruction, the Medium Access Control Element (MAC CE) including a target cell ID represented by a number of bits less than the number of bits used for a physical cell ID, and information indicating at least one of a first Transmission Configuration Indication state (TCI state) applied to both a downlink (DL) and an uplink (UL), a second TCI state applied to the DL, and a third TCI state applied to the UL, associated with the target cell having a physical cell ID different from the physical cell ID of the serving cell; a control unit that applies at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information to a specific channel for the target cell; A terminal having:

2. Further comprising a transmitter that transmits capability information indicating whether or not the device supports updating at least one of the first TCI state, the second TCI state, and the third TCI state after the serving cell is changed by the MAC CE. The terminal according to claim 1 .

3. The control unit changes the configuration of the serving cell to the configuration of the target cell based on the configuration of multiple cells received by Radio Resource Control (RRC) signaling. The terminal according to claim 1 .

4. A process of receiving a Medium Access Control Control Element (MAC CE) for a serving cell change instruction, the Medium Access Control Element (MAC CE) including a target cell ID represented by a number of bits less than the number of bits used for a physical cell ID, and information indicating at least one of a first Transmission Configuration Indication state (TCI state) applied to both downlink (DL) and uplink (UL), a second TCI state applied to DL, and a third TCI state applied to UL, associated with the target cell having a physical cell ID different from the physical cell ID of the serving cell; applying at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information to a particular channel for the target cell; A wireless communication method for a terminal having the above configuration.

5. A transmitter that transmits a Medium Access Control Control Element (MAC CE) for a serving cell change instruction, the Medium Access Control Element (MAC CE) including a target cell ID represented by a number of bits less than the number of bits used for a physical cell ID, and information indicating at least one of a first Transmission Configuration Indication state (TCI state) applied to both a downlink (DL) and an uplink (UL), a second TCI state applied to the DL, and a third TCI state applied to the UL, associated with the target cell having a physical cell ID different from the physical cell ID of the serving cell; a control unit that controls at least one of transmission and reception of a specific channel for the target cell when at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information is applied to the specific channel; A base station having

6. A system including a terminal and a base station, The base station a transmitter that transmits a Medium Access Control Control Element (MAC CE) for a serving cell change instruction, the MAC CE including a target cell ID represented by a number of bits less than the number of bits used for a physical cell ID, and information indicating at least one of a first Transmission Configuration Indication state (TCI state) applied to both a downlink (DL) and an uplink (UL), a second TCI state applied to the DL, and a third TCI state applied to the UL, the target cell having a physical cell ID different from the physical cell ID of a serving cell; The terminal a receiving unit for receiving the MAC CE; a control unit that applies at least one of the first TCI state, the second TCI state, and the third TCI state indicated in the information to a specific channel for the target cell. system.

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