Terminal, wireless communication method and system

Abstract

A terminal according to one aspect of the present disclosure comprises: a receiving unit that receives a cell switch command of a special cell (SpCell) by layer 1 / layer 2 (L1 / L2) signaling; and a control unit that makes different assumptions about the activation or deactivation status of a candidate cell on the basis of the type of the candidate cell. According to one aspect of the present disclosure, settings / processing at the time of cell switching can be appropriately performed.

Description

Terminal, wireless communication method and base station

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

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

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

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

[0005] In a wireless communication system, it is being considered that one or more cells / transmission / reception points (Transmission / Reception Points (TRPs)) (Multi-TRPs (MTRPs)) perform downlink (DL) transmissions to a terminal (user terminal, User Equipment (UE)).

[0006] Incidentally, when multi-TRP is applied, cell switching using layer 1 / layer 2 inter-cell mobility (L1 / L2 inter-cell mobility) is being considered. For example, it is possible that the current SCell / PCell becomes a candidate cell. In this case, the configuration / control has not been clarified. This may result in inappropriate processing after cell switching, which may cause problems such as reduced communication throughput.

[0007] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, and a base station that can appropriately perform settings / processing during a cell switch.

[0008] A terminal according to one aspect of the present disclosure is characterized by having a receiving unit that receives a cell switch command for a special cell (SpCell) via Layer 1 / Layer 2 (L1 / L2) signaling, and a control unit that makes different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell.

[0009] According to one aspect of the present disclosure, settings / processing can be performed appropriately when switching cells.

[0010] Figures 1A to 1D are diagrams illustrating an example of a multi-TRP configuration. Figure 2A is a diagram illustrating an example of UE movement in Rel. 17. Figure 2B is a diagram illustrating an example of UE movement in Rel. 18. Figure 3 is a diagram illustrating an example of association between a serving cell and a candidate cell. Figure 4A is a diagram illustrating a first example of ServingCellConfig for Option 1. Figure 4B is a diagram illustrating a second example of ServingCellConfig for Option 1. Figure 5 is a diagram illustrating a first example of Option 2. Figure 6A is a diagram illustrating a second example of Option 2. Figure 6B is a diagram illustrating a third example of Option 2. Figure 7 is a diagram illustrating a serving cell switch example 1. Figure 8 is a diagram illustrating a serving cell switch example 2. Figure 9 is a diagram illustrating a serving cell switch example 3. Figure 10 is a diagram illustrating an example of a serving cell configuration in Aspect 1.1. Figure 11 is a diagram illustrating an example of a serving cell configuration in Aspect 1.2. Figure 12 is a diagram illustrating an example of a cell type configuration in Embodiment 2.1. Figure 13 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. Fig. 14 is a diagram illustrating an example of the configuration of a base station according to an embodiment. Fig. 15 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. Fig. 16 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. Fig. 17 is a diagram illustrating an example of a vehicle according to an embodiment.

[0011] (Multi-TRP) In NR, one or more transmission / reception points (Transmission / Reception Points (TRP)) (multi-TRP) are considered to perform DL transmission to a UE using one or more panels (multi-panels). Also, it is considered that a UE performs UL transmission to one or more TRPs.

[0012] Note that multiple TRPs may correspond to the same cell identifier (ID), or different cell IDs, which may be physical cell IDs (PCIs) or virtual cell IDs.

[0013] 1A-1D illustrate an example of a multi-TRP scenario, assuming, but not limited to, that each TRP is capable of transmitting four different beams.

[0014] 1A shows an example of a case where only one TRP (TRP1 in this example) of multiple TRPs transmits to the UE (this may be referred to as single mode, single TRP, etc.). In this case, TRP1 transmits both control signals (PDCCH) and data signals (PDSCH) to the UE.

[0015] 1B shows an example of a case where only one TRP (TRP1 in this example) transmits control signals to the UE, and the multi-TRP transmits data signals (also called single master mode). The UE receives each PDSCH transmitted from the multi-TRP based on a single Downlink Control Information (DCI).

[0016] Figure 1C shows an example of a case where each of the multi-TRPs transmits a part of the control signal to the UE, and the multi-TRPs transmit data signals (this may be called a master-slave mode). Part 1 of the control signal (DCI) may be transmitted in TRP1, and Part 2 of the control signal (DCI) may be transmitted in TRP2. Part 2 of the control signal may depend on Part 1. The UE receives each PDSCH transmitted from the multi-TRP based on these parts of the DCI.

[0017] 1D shows an example of a multi-TRP mode in which each TRP transmits a separate control signal to the UE, and the multi-TRP transmits a data signal (also referred to as a multi-master mode). A first control signal (DCI) may be transmitted on TRP1, and a second control signal (DCI) may be transmitted on TRP2. The UE receives each PDSCH transmitted from the multi-TRP based on these DCIs.

[0018] When multiple PDSCHs from multiple TRPs as shown in Figure 1B (which may also be referred to as multiple PDSCHs) are scheduled using one DCI, the DCI may be referred to as a single DCI (S-DCI, single PDCCH). Also, when multiple PDSCHs from multiple TRPs as shown in Figure 1D are scheduled using multiple DCIs, these multiple DCIs may be referred to as multiple DCIs (M-DCI, multiple PDCCHs).

[0019] Each TRP in a multi-TRP may transmit a different transport block (TB) / code word (CW) / different layer, or each TRP in a multi-TRP may transmit the same TB / CW / layer.

[0020] Non-Coherent Joint Transmission (NCJT) is being considered as one form of multi-TRP transmission. In NCJT, for example, TRP1 modulates and layer-maps a first codeword to transmit a first PDSCH using a first number of layers (e.g., two layers) with a first precoding. TRP2 modulates and layer-maps a second codeword to transmit a second PDSCH using a second number of layers (e.g., two layers) with a second precoding.

[0021] Note that multiple PDSCHs (multi-PDSCHs) that are non-coherent may be defined as partially or completely overlapping in time and / or frequency domains, i.e., a first PDSCH from a first TRP and a second PDSCH from a second TRP may overlap in time and / or frequency resources.

[0022] The first PDSCH and the second PDSCH may be assumed to be not quasi-co-located (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).

[0023] In URLLC for multi-TRP, it is considered that PDSCH (transport block (TB) or codeword (CW)) repetition across multi-TRP is supported. Repetition schemes (URLLC schemes, e.g., Schemes 1, 2a, 2b, 3, and 4) across multi-TRP in the frequency domain, layer (spatial) domain, or time domain are supported. In Scheme 1, multiple PDSCHs from multi-TRP are space division multiplexed (SDM). In Schemes 2a and 2b, PDSCHs from multi-TRP are frequency division multiplexed (FDM). In Scheme 2a, the redundancy version (RV) is the same for multi-TRP. In Scheme 2b, the RVs for multi-TRP may be the same or different. In schemes 3 and 4, multiple PDSCHs from multiple TRPs are time division multiplexed (TDM). In scheme 3, multiple PDSCHs from multiple TRPs are transmitted in one slot. In scheme 4, multiple PDSCHs from multiple TRPs are transmitted in different slots.

[0024] Such a multi-TRP scenario allows for more flexible transmission control using good quality channels.

[0025] NCJT using multiple TRPs / panels may use high rank. To support ideal and non-ideal backhaul between multiple TRPs, both single DCI (single PDCCH, e.g., FIG. 1B) and multiple DCI (multiple PDCCH, e.g., FIG. 1D) may be supported. For both single DCI and multiple DCI, the maximum number of TRPs may be two.

[0026] For single PDCCH design (mainly for ideal backhaul), TCI extension is being considered. Each TCI codepoint in the DCI may correspond to one or two TCI states. The TCI field size may be the same as that of Rel. 15.

[0027] (L1 / L2 Inter-Cell Mobility) As described above, it is being considered that a UE performs UL transmission to one or more cells / TRPs. The following scenario 1 or scenario 2 can be considered as a procedure in this case. In the present disclosure, the term "serving cell" may be replaced with the TRP in the serving cell. The terms "layer 1 / layer 2" (L1 / L2) and "DCI / Medium Access Control Control Element (MAC CE)" may be interchangeable. In the present disclosure, a physical cell identity (PCI) different from the physical cell identity (PCI) of the current serving cell may be simply referred to as a "different PCI." The terms "non-serving cell," "cell having a different PCI," and "additional cell" may be interchangeable.

[0028] <Scenario 1> Scenario 1 corresponds to, for example, multi-TRP inter-cell mobility, but may be a scenario that does not correspond to multi-TRP inter-cell mobility.

[0029] (1) The UE receives from the serving cell the configuration necessary for using radio resources for data transmission and reception, including the SSB configuration for beam measurement of the TRP corresponding to a PCI different from that of the serving cell and the resources of the different PCI. (2) The UE performs beam measurement of the TRP corresponding to the different PCI and reports the beam measurement results to the serving cell. (3) Based on the above report, the Transmission Configuration Indication (TCI) state associated with the TRP corresponding to the different PCI is activated by L1 / L2 signaling from the serving cell. (4) The UE transmits and receives using a UE-specific (dedicated) channel on the TRP corresponding to the different PCI. (5) The UE must always cover the serving cell, even 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).

[0030] In Scenario 1, when the UE transmits and receives signals to and from an additional cell / TRP (a TRP corresponding to the PCI of the additional cell), the serving cell (the serving cell assumption in the UE) is not changed. The UE is configured with higher layer parameters related to the PCI of non-serving cells from the serving cell. Scenario 1 may be applied, for example, in Rel. 17.

[0031] Figure 2A shows an example of UE movement in Rel. 17. Assume that a UE moves from a cell with PCI #1 (serving cell) to a cell with PCI #3 (additional cell) (which overlaps with the serving cell). In this case, in Rel. 17, the serving cell is not switched via L1 / L2. The additional cell is a cell with an additional PCI that is different from the PCI of the serving cell. The UE can receive / transmit UE-specific (dedicated) channels from the additional cell. The UE must be within the coverage of the serving cell to receive UE common channels (e.g., system information / paging / short messages).

[0032] <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 an additional cell is possible without handover. Since handover requires RRC reconnection, which results in 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. In scenario 2, for example, the following procedure is performed.

[0033] (1) The UE receives SSB configuration for a cell with a different PCI (additional cell) from the serving cell for beam measurement / serving cell change. (2) The UE performs beam measurement for the cell using the different PCI and reports the measurement results to the serving cell. (3) The UE may receive the configuration for the cell with a different PCI (serving cell configuration) via higher layer signaling (e.g., RRC). That is, pre-configuration for the serving cell change is performed. This configuration may be performed together with or separately from the configuration in (1). (4) Based on the above report, the TCI state of the cell with the different PCI is activated via L1 / L2 signaling in accordance with the serving cell change. The TCI state activation and the serving cell change may be performed separately. (5) The UE changes the serving cell (assumed serving cell) and starts reception / transmission using the pre-configured UE-specific channel and TCI state.

[0034] That is, in Scenario 2, the serving cell (the serving cell assumed by the UE) is updated by L1 / L2 signaling. Scenario 2 may be applied in Rel. 18.

[0035] Figure 2B shows an example of UE mobility in Rel. 18. In Rel. 18, the serving cell is switched via L1 / L2. The UE can receive / transmit UE-specific channels / common channels to / from the new serving cell. The UE may move out of the coverage of the previous serving cell.

[0036] (Setting of Multiple Candidate Cells) FIG. 3 is a diagram showing an example of association between a serving cell and a candidate cell. SpCell #0, SCell #1, or SCell #2 is assumed to be a serving cell. Note that SpCell means a special cell (including a primary cell (PCell) and a primary secondary cell (PSCell)). SCell means a secondary cell. SpCell #0 is associated with candidate cell #0-1, candidate cell #0-2, and candidate cell #0-3. SCell #1 is associated with candidate cell #1-1. SCell #2 is associated with candidate cell #2-1 and #2-2. In this way, one or more candidate cells (candidate serving cells) may be associated with a serving cell.

[0037] Regarding the setting of candidate cells (candidate cells) when changing the serving cell, for example, the following options 1 and 2 are possible.

[0038] <Option 1> As with inter-cell mobility in Rel. 17, the information in ServingCellConfig may include information about multiple candidate cells. In this case, the multiple candidate cells need to share the same PDCCH / PDSCH / UL configuration as the serving cell.

[0039] For example, in Rel. 17 inter-cell mobility, it is being considered to add "mimoParam-r17" under ServingCellConfig and add PCI configuration information (Fig. 4A, Fig. 4B). This framework is applied when cells with different PCIs share the same PDCCH / PDSCH / UL configurations.

[0040] For each candidate cell, more configurations may be applied, such as LTE CRS pattern, RACH configuration, etc. Also, cell-specific CSI-RS configurations (for CSI / TRS) may be taken into account, allowing different CSI-RS opportunities / resources to be configured for each cell to reduce interference.

[0041] Fig. 4A is a diagram showing a first example of a ServingCellConfig for Option 1. In Fig. 4A, the ServingCellConfig includes configurations for additional cells (each candidate cell). Fig. 4B is a diagram showing a second example of a ServingCellConfig for Option 1. In Fig. 4B, the ServingCellConfig includes configurations for additional cells (each candidate cell) for L1 / L2 inter-cell mobility. Fig. 4A corresponds, for example, to the above-mentioned Scenario 1. Fig. 4B corresponds, for example, to the above-mentioned Scenario 2.

[0042] As shown in Figures 4A and 4B, candidate cells are pre-configured by RRC. As an initial state, candidate cells may be fixed to be activated / deactivated in the specification, or may be configured to be activated / deactivated by RRC. Furthermore, candidate cells for L1 / L2 cell switch may be activated / deactivated by MAC CE. L1 / L2 cell switch indication may be sent only from the active cell.

[0043] <Option 2> Multiple candidate cells may be associated with each serving cell by reusing the carrier aggregation (CA) configuration framework, with a complete configuration (e.g., ServingCellConfig) corresponding to each cell. The UE is provided with the complete configuration for each candidate cell, allowing it to communicate properly with the candidate cells.

[0044] In the CA configuration framework, an SpCell can be configured for each cell group and multiple SCells can be added. By reusing the CA framework, a serving cell can be configured for each cell group for L1 / L2 inter-cell mobility, and multiple candidate cells can be configured (Figure 5). Candidate cells can be activated / deactivated by MAC CE. This method is considered beneficial for reducing the complexity of UE operations. As an example, the CellGroupConfig for cell group ID 0 is shown.

[0045] Figure 6A shows a second example of Option 2. In the example of Figure 6A, a common candidate cell pool for cell switching in the MCG / SCG is applied to the candidate cells, i.e., the candidate cells are treated as one pool (group) regardless of frequency band.

[0046] Figure 6B is a diagram showing a third example of Option 2. In the example of Figure 6B, multiple cell groups are configured, and cell group switching is possible through L1 / L2 signaling. Candidate cells are configured for each cell group, and the configuration for each group includes the indices of the corresponding SpCell and SCell. The CellGroupConfig in Figure 6B shows the CellGroupConfig for cell group ID: 1 as an example, but CellGroupConfigs for cell group IDs: 2 and 3 are also configured separately.

[0047] (Signaling for Serving Cell Change Indication) Implicit or explicit signaling for serving cell change indication will now be described.

[0048] [Aspect 1] In aspect 1, implicit signaling for a serving cell change indication is described.

[0049] [[Option 1-1]] 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 a MAC CE together with one or more TCI states associated with cells of PCIs different from that of the serving cell (when one or more TCI states associated with cells of PCIs different from that of the serving cell are indicated / activated by a 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.

[0050] In this case, the UE may update 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.

[0051] [[Option 1-2]] When the MAC CE activates / deactivates the TCI states of the 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 will be changed to another cell.

[0052] 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 second cell with a different PCI).

[0053] [[Options 1-3]] If the 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), i.e., this association may implicitly indicate that the serving cell will be changed to another cell.

[0054] [Aspect 2] In aspect 2, explicit signaling for a serving cell change instruction will be described. In aspect 2, for example, the above-mentioned scenario 2 is applied.

[0055] [Option 2-1] An example of a serving cell change instruction will be described below. Note that activation / deactivation of a non-serving cell, change of a 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.

[0056] The UE may receive a new MAC CE including at least one of the fields (information) indicating the following (1) to (3) corresponding to a 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). Furthermore, the UE may 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 including multiple fields indicating multiple non-serving cell indexes is applied.

[0057] (1) Serving cell ID, (2) BWP ID, and (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).

[0058] As an example of (3), any of (3-1) to (3-5) may be applied. (3-1) PCI (PCI used directly). For example, 10 bits are used. (3-2) Re-creation index (new ID) of non-serving cells. The new ID may be associated with a part of the PCI and configured only for serving 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) (when CSI-ReportConfig corresponds to one or more non-serving cells). (3-4) CSI resource configuration ID (CSI-ResourceConfigId) (when CSI-ResourceConfigId corresponds to one or more non-serving cells). (3-5) Bitmap indicating 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, when activating the second non-serving cell among three non-serving cells, "010" is set.

[0059] 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 having 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.

[0060] [[Option 2-2]] 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.

[0061] [Option 2-3] In addition to the MAC CE in Option 2-2, the MAC CE may further include a field indicating the serving cell index / PCI / other ID (such as the new ID in Option 2-1 above), and a field indicating the TCI state / SSB / CSI-RS of the target cell (the serving cell after the change).

[0062] In this way, since the instruction for the serving cell change instruction is indicated by the MAC CE / DCI, the UE can appropriately change the serving cell.

[0063] [Serving Cell Switch Example 1] Figure 7 is a diagram showing Serving Cell Switch Example 1. For example, in a serving cell SpCell #0 of an MCG / SCG, if an instruction to change the serving cell to candidate cell #0-2 is given by L1 / L2 signaling, candidate cell #0-2 becomes the new serving cell SpCell #0. Also, for example, in a serving cell SCell #2 of an MCG / SCG, if an instruction to change the serving cell to candidate cell #2-1 is given by L1 / L2 signaling, candidate cell #2-1 becomes the new serving cell SCell #2.

[0064] [Serving Cell Switch Example 2] The RRC / MAC CE can configure a global candidate cell ID (cell #0,...,5) for each cell group, band, FR, and UE. The UE may be instructed to switch serving cells by the global candidate cell ID.

[0065] Figure 8 illustrates a serving cell switch example 2. Similar to Figure 6A, a pool of multiple candidate cells can be configured, and the serving cell can be switched to any (activated) candidate cell in the pool by L1 / L2 signaling. In this case, the configured candidate cell can become either an SpCell or a Sell based on the L1 / L2 signaling.

[0066] The UE may receive an indication of a serving cell change (from cell #2-1 to candidate cell 4) via MAC CE / DCI, and the indicated candidate cell #4 becomes the SpCell of the new cell group.

[0067] [Serving Cell Switch Example 3] The RRC / MAC CE can set a global candidate cell ID (cell #0-1, #0-1, ..., 2-2) for each cell group, band, FR, and UE. The UE may be instructed to switch the serving cell by the global candidate cell ID.

[0068] 9 is a diagram showing a serving cell switch example 3. The UE receives an instruction to change the serving cell (from cell #2-0 to cell #2-1) by MAC CE / DCI. The indicated cell #2-1 then becomes the SpCell of the new cell group. Furthermore, the cells (cell #0-0, cell #1-0) in the same cell group as the indicated cell #2-1 become Scell ​​#1 and Scell ​​#2. In other words, the serving cell group is switched.

[0069] (Analysis) As described above, when multi-TRP is applied, cell switching is considered to be performed by L1 / L2 inter-cell mobility. For example, it is possible that the current SCell / PCell becomes a candidate cell (i.e., the target Pcell / SCell, candidate cell, is the current SCell / PCell). In this case, the configuration / control is not clear. This may result in inappropriate processing after cell switching, which may cause problems such as reduced communication throughput.

[0070] For example, it is unclear how to set the current Scell / Pcell as a candidate cell. Also, when a cell is switched, it is unclear how to handle the existing Scell, especially when the target cell is the current Scell. If these are unclear, continuous cell switching due to L1 / L2 inter-cell mobility may not be performed smoothly.

[0071] Therefore, the present inventors have conceived a terminal, a wireless communication method, and a base station that can appropriately perform settings / processing at the time of cell switching.

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

[0073] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0074] In the present disclosure, terms such as notify, activate, deactivate, indicate (or indicate), select, configure, update, and determine may be read interchangeably. In the present disclosure, terms such as support, control, controllable, operate, and operate may be read interchangeably.

[0075] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, fields, information elements (IEs), settings, etc. may be interchangeable. In the present disclosure, Medium Access Control (MAC) control elements (CEs), update commands, activation / deactivation commands, etc. may be interchangeable.

[0076] In the present disclosure, 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.

[0077] In the present disclosure, MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. Broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0078] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), and the like.

[0079] In the present disclosure, the terms index, identifier (ID), indicator, resource ID, etc. may be interchangeable. In the present disclosure, the terms sequence, list, set, group, cluster, subset, pool, etc. may be interchangeable.

[0080] In the present disclosure, the terms panel, UE panel, panel group, beam, beam group, precoder, Uplink (UL) transmitting entity, Transmission / Reception Point (TRP), base station, Spatial Relation Information (SRI), spatial relation, SRS Resource Indicator (SRI), Control Resource Set (CORESET), Physical Downlink Shared Channel (PDSCH), Codeword (CW), Transport Block (TB), Reference Signal (RS), antenna port (e.g., Demodulation Reference Signal (DMRS) port), antenna port group (e.g., DMRS port group), group (e.g., spatial relation group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) group, PUCCH resource group), resource (e.g., reference signal resource, SRS resource), resource set (e.g., reference signal resource set), CORESET pool, downlink Transmission Configuration Indication state (TCI state) (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, Quasi-Co-Location (QCL), QCL assumption, etc. may be read as interchangeable.

[0081] Furthermore, the spatial relationship information identifier (ID) (TCI state ID) and the spatial relationship information (TCI state) may be interchangeable. The "spatial relationship information" may be interchangeable with "set of spatial relationship information," "one or more pieces of spatial relationship information," etc. The TCI state and the TCI may be interchangeable with each other.

[0082] In the present disclosure, the terms drop, abort, cancel, puncture, rate match, postpone, do not transmit, etc. may be read interchangeably.

[0083] In the present disclosure, a cell group, a serving cell group, a master cell group (MCG), and a secondary cell group (SCG) may be interchangeable. L1 / L2, L1 / L2 signaling, and DCI / MAC CE may be interchangeable. A serving cell may be replaced with a cell that transmits a PDSCH. A candidate cell may refer to a cell that is a candidate to become a serving cell through L1 / L2 inter-cell mobility.

[0084] In the present disclosure, cell, PCI, serving cell, SpCell, source serving cell, CC, BWP, BWP within CC, and band may be interchangeable. In the present disclosure, additional cell, other cell, non-serving cell, cell with a different PCI, candidate cell, candidate serving cell, cell with a PCI different from the PCI of the current serving cell, another serving cell, target cell, and neighboring cell may be interchangeable. In the present disclosure, switch, change, and update may be interchangeable. Serving cell may be interchangeable with the serving cell before the switch or the serving cell after the switch.

[0085] The serving cell, SpCell, PSCell, PCell, and SCell may be interchangeable. The cell switch command, cell change instruction, and serving cell change instruction may be interchangeable.

[0086] (Wireless Communication Method) <Embodiment 1> A process for setting a current serving cell as a candidate cell will be described. This embodiment may be applied to, for example, the above-mentioned L1 / L2 inter-cell mobility scenario 2. The UE may receive, via higher layer signaling / physical layer signaling, a configuration / instruction / parameter indicating whether the serving cell can be a candidate cell for Layer 1 / Layer 2 (L1 / L2) inter-cell mobility, and may control a serving cell switch based on the configuration / instruction / parameter.

[0087] [Aspect 1.1] The UE may receive, via higher layer signaling / physical layer signaling, a configuration / instruction / parameter indicating whether all serving cells in a cell group (MCG / SCG) can be candidate cells (or candidates for a target SpCell / SCell) for L1 / L2 inter-cell mobility for each cell group (MCG / SCG). In other words, the UE may receive (one) configuration / instruction / parameter common to all serving cells in a cell group.

[0088] If the setting / instruction / parameter common to the serving cell indicates "No" (there is no cell that can be a candidate cell), only candidate cells that have been set in advance by RRC signaling, etc. are applied as candidate cells. For example, a type C cell, which will be described later, may not be applied as a candidate cell.

[0089] Fig. 10 is a diagram showing an example of a serving cell configuration according to aspect 1.1. In Fig. 10, the UE receives a configuration / instruction / parameter indicating that a cell group including SpCell #0, SCell #1, and SCell #2 can be a candidate cell for L1 / L2 inter-cell mobility. Note that candidate cells #3 to #7 may be configured in advance by RRC signaling or the like to be candidate cells.

[0090] [Aspect 1.2] The UE may receive, via higher layer signaling / physical layer signaling, configuration / indication / parameters indicating whether each serving cell / CC in a cell group (MCG / SCG) can be a candidate cell (or a candidate for the target SpCell / SCell) for L1 / L2 inter-cell mobility. That is, the UE may receive individual configuration / indication / parameters for each serving cell.

[0091] Fig. 11 is a diagram showing an example of a serving cell configuration according to aspect 1.2. In Fig. 11, the UE receives a configuration / instruction / parameter indicating that SCell #1 can be a candidate cell for L1 / L2 inter-cell mobility. The UE may also receive a configuration / instruction / parameter indicating that SpCell #0 and SCell #2 cannot be candidate cells for L1 / L2 inter-cell mobility. Note that candidate cells #3 to #7 may be configured in advance by RRC signaling or the like to be candidate cells.

[0092] [Supplementary Note] In aspects 1.1 and 1.2, a candidate cell set in a cell group may be included in both the candidate cell pools (groups) of the SpCell cell switch for L1 / L2 inter-cell mobility and the Scell ​​cell switch for L1 / L2 inter-cell mobility. In other words, a serving cell that is a candidate cell may be switched to either the SpCell or the Scell.

[0093] The UE may transmit (report) UE capability information indicating that it supports a serving cell (SpCell / SCell) as a candidate cell (i.e., it can be a candidate cell). For example, when aspect 1.1 is applied, the UE may transmit UE capability information indicating that it supports all serving cells in a cell group as candidate cells. For example, when aspect 1.2 is applied, the UE may transmit UE capability information indicating that it supports each serving cell in a cell group as a candidate cell (i.e., it can be a candidate cell).

[0094] According to this embodiment, when the serving cell (SpCell / SCell) becomes a candidate cell, appropriate settings can be made.

[0095] <Embodiment 2.1> The UE receives a cell switch command for the SpCell via L1 / L2 signaling and may make different assumptions about the activation / deactivation status of the candidate cell (target cell) based on the type of the candidate cell.

[0096] When a cell switch command (serving cell change indication) is sent by L1 / L2 signaling, the UE may keep / store / maintain the RRC configuration of the current SCell and the RRC configuration of the candidate cell unless it receives an RRC reconfiguration signal. The cell switch may be either a single cell switch, a multi-cell switch or a cell group switch.

[0097] For the purposes of explanation in the present disclosure, the following four types of cells are defined. This embodiment is applicable to both aspect 1.1 and aspect 1.2 of the first embodiment. Each type of cell is applied, for example, as shown in FIG. 12. In the present disclosure, Type A, Type B, Type C, and Type D may be interpreted as interchangeable. Type A: SpCell. Type B: Scell ​​not designated as a candidate cell. Type C: Scell ​​designated as a candidate cell. Type D: Candidate cell configured by RRC (not the original SCell).

[0098] [Case a] When a cell switch command for an SpCell is sent via L1 / L2 signaling and the candidate cell (target cell, the cell that will become the new SpCell) is not an Scell ​​(i.e., the target cell is a Type D cell), the following options 1 or 2 are applied to the Type D candidate cell, the following options 3B to 5B are applied to the Type B serving cell, the following options 3C to 5C are applied to the Type C serving cell / candidate cell, and the following option 6 is applied to the Type A SpCell.

[0099] Option 1: The UE may assume that the activation / deactivation status of each type D cell remains unchanged, and thus sequential L1 / L2 cell changes may be possible.

[0100] <<Option 2>> The UE may receive an indication of activation / deactivation of each type D cell in the same signaling (simultaneous signaling) as the cell switch command.

[0101] In addition, in Option 1 or 2, the candidate cell (target cell, the cell that will become the new SpCell) may be activated when it becomes the new SpCell, regardless of whether or not an activation signal is present.

[0102] <<Option 3B>> The UE may assume that the activation / deactivation status of each type-B cell remains unchanged.

[0103] Option 4B: The UE may assume that each Type-B cell is deactivated if it does not receive a new activation / deactivation instruction.

[0104] <<Option 5B>> The UE may receive an indication of activation / deactivation of each type-B cell in the same signaling (simultaneous signaling) as the cell switch command.

[0105] <<Option 3C>> The UE may assume that the activation / deactivation status of each type-C cell remains unchanged.

[0106] Option 4C: The UE may assume that each type-C cell is deactivated if it does not receive a new activation / deactivation instruction.

[0107] <<Option 5C>> The UE may receive an indication of activation / deactivation of each type-C cell in the same signaling (simultaneous signaling) as the cell switch command.

[0108] Option 6: After a cell switch command is sent to the UE, the Type A SpCell becomes a Type D candidate cell. The UE may assume that the state of the cell is activated or deactivated. Alternatively, the UE may be instructed to activate / deactivate this cell by the cell switch command.

[0109] [Case b] Case b is a case where a cell switch command for the SpCell is sent by L1 / L2 signaling and the candidate cell (target cell, the cell that will become the new SpCell) is a type C SCell. In this case, the UE may assume that the state of the target cell, the type C SCell, will be activated because it will become the new SpCell, regardless of whether activation signaling is present. For other cells, the options in case a may be applied in the same way.

[0110] [Case c] When the UE receives a cell switch command for the SCell via L1 / L2 signaling, the same options as those in Case a or Case b may be applied, i.e., the SpCell in Case a or Case b may be replaced with the SCell.

[0111] [Supplementary Note] The cell switch command may include an indication of the activation / deactivation status of each candidate cell / each serving cell, or the cell switch command may be sent to the UE together with the indication.

[0112] For example, a bitmap may be used as the activation / deactivation indication, where each bit may indicate activation / deactivation of each candidate cell / each serving cell. Alternatively, the activation / deactivation indication may explicitly indicate some or all cell indices. Transmission of a cell index may implicitly indicate activation / deactivation of the cell.

[0113] For example, a cell switch command may use signaling (e.g., MAC CE / DCI) separate from the indication of the activation / deactivation state. For example, the UE may be instructed only on the activation / deactivation states of specific / some cells (such as the source cell of the cell switch, a type B cell, a type C cell, or a type D cell).

[0114] The UE may transmit UE capability information indicating whether it supports updating the activation / deactivation status of other cells (candidate cells / serving cells) during a cell switch.

[0115] <Embodiment 2.2> In embodiment 2.2, not only activation / deactivation but also changing of cell roles (e.g., serving cell / candidate cell, type A / B / C / D cell roles) is described. For example, when a cell is switched, the target cell (candidate cell) becomes the serving cell and is also activated. For the original (before-switching) serving cell, the following options may be applied:

[0116] <<Option 1>> The original serving cell becomes the candidate cell. Activation / deactivation may be determined based on embodiment 2.1.

[0117] Option 2: The original serving cell remains the serving cell and may be activated / deactivated. This option assumes, for example, a case where the roles of SpCell #0 and Scell ​​#1 are swapped, with SpCell #0 becoming the Scell ​​and Scell ​​#1 becoming the new SpCell.

[0118] Option 3: The original serving cell may become a Type C cell or a Type B cell.

[0119] <<Option 4>> The UE may also receive a specific signal indicating whether or not a cell role change has occurred. The specific signal may be the same as the cell switch command / cell status indication, or may be a separate signal. The specific signal may indicate only whether or not the role of the original serving cell (source cell) has changed (e.g., whether or not to change to a candidate cell or whether or not to change to a Type-C cell). For example, the specific indication may indicate a role change indication for multiple / all cells.

[0120] <<Option 5>> The original serving cell may change roles depending on the type of the target cell. For example, the UE may exchange roles with the original serving cell and the target cell when the target cell is Type B or Type C. For example, the UE may not exchange roles with the original serving cell and the target cell when the target cell is Type A or Type D.

[0121] <Embodiment 3> For a serving cell and a candidate cell in a cell group, a specific index corresponding to a cell / PCI configured by the RRC may be indicated. The specific index is, for example, an index associated with a part of the PCI. The specific index is configured by the RRC to associate a PCI cell with a reconfiguration index. Since the specific index has a reduced number of bits compared to the PCI, it can be easily indicated to a cell using a bitmap in the MAC CE / DCI, etc. After a cell switch, one of the following options may be applied regarding whether the specific index is updated.

[0122] <<Option 1>> If the UE does not receive an RRC reconfiguration signal (until a new RRC reconfiguration is performed), the UE may retain a specific index. For example, a specific index "0" may or may not be for the current SpCell.

[0123] Option 2: In the case of an SpCell switch only, the UE may exchange the specific indexes of the original SpCell and the target cell. For example, the specific index "0" may always be set for the SpCell.

[0124] Option 3: When a cell switch occurs, the UE may exchange the specific indexes of the serving cell and the target cell, where the index of the serving cell may always be smaller (lower) than the index of the candidate cell.

[0125] <<Option 4>> The cell switch command may indicate specific indices of some / all serving / candidate cells. The indication of the specific indices may be included in the same signal as the cell switch command or in a separate signal (e.g., in the MAC CE / DCI). The UE may also send UE capability information indicating that it supports the features of Option 4.

[0126] <Group Switch Case> Each embodiment may also be applied to the cell group switch case (for example, FIG. 9).

[0127] Embodiments 2.1 and 2.2 may be applied to a cell group switch. When a UE receives a cell group switch command through L1 / L2 signaling, the following processes may be performed: - The target cell group is activated. - The original (pre-change) serving cell group may be deactivated, may remain activated, or the activation / deactivation status may be explicitly indicated to the UE through new signaling. - Other candidate cell groups may be deactivated, may remain activated / deactivated, or may have their activation / deactivation status explicitly indicated to the UE through new signaling. - The activation / deactivation of a cell group may be the same signal as the cell group indication (switch indication) or a separate new signal (MAC CE / DCI).

[0128] The UE may be instructed to change the SpCell / Scell ​​role for each cell group (or a specific cell group, e.g., the target cell group). The UE may also send UE capability information regarding activation / deactivation updates for cell groups.

[0129] The third embodiment may be applied to a cell group switch. For example, a specific index may be replaced with a specific cell group index, and a PCI may be replaced with a cell group index (original cell group index). The cell group indexes of the serving cell group and the candidate cell group may be retained, switched (switched between the target cell group and the original serving cell group), or explicitly indicated to the UE by new signaling. The UE may transmit UE capability information regarding the update of the cell group index.

[0130] <Supplementary Information> [Notification of Information to UE] In the above-described embodiments, any information may be notified to the UE (from a network (NW) (e.g., a base station (BS))) (in other words, reception of any information from the BS by the UE) using physical layer signaling (e.g., DCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

[0131] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new Logical Channel ID (LCID) in the MAC subheader, which is not defined in existing standards.

[0132] When the notification is made by DCI, the notification may be made by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used to scramble Cyclic Redundancy Check (CRC) bits assigned to the DCI, the format of the DCI, etc.

[0133] Furthermore, notification of any information to the UE in the above embodiments may be performed periodically, semi-persistently, or aperiodically.

[0134] [Notification of Information from UE] In the above-described embodiments, notification of any information from the UE (to the NW) (in other words, transmission / report of any information from the UE to the BS) may be performed using physical layer signaling (e.g., UCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PUCCH, PUSCH, PRACH, reference signal), or a combination thereof.

[0135] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new LCID, which is not defined in existing standards, in the MAC subheader.

[0136] If the notification is made by UCI, the notification may be transmitted using PUCCH or PUSCH.

[0137] Furthermore, any information in the above-described embodiments may be notified from the UE periodically, semi-persistently, or aperiodically.

[0138] [Application of Each Embodiment] At least one of the above-described embodiments may be applied when a specific condition is met. The specific condition may be defined in a standard or may be notified to a UE / BS using higher layer signaling / physical layer signaling.

[0139] At least one of the above-described embodiments may be applied only to UEs that have reported or support a particular UE capability.

[0140] The particular UE capability may indicate support for particular processes / operations / controls / information for at least one of the above embodiments.

[0141] Furthermore, the above-mentioned specific UE capability may be a capability that is applied across all frequencies (commonly regardless of frequency), or may be a capability for each frequency (e.g., one or a combination of a cell, a band, a band combination, a BWP, a component carrier, etc.), or may be a capability for each frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), or may be a capability for each subcarrier spacing (SubCarrier Spacing (SCS)), or may be a capability for each Feature Set (FS) or Feature Set Per Component-carrier (FSPC).

[0142] Furthermore, the specific UE capability may be a capability that is applied to all duplexing methods (commonly regardless of the duplexing method), or may be a capability for each duplexing method (e.g., Time Division Duplex (TDD) or Frequency Division Duplex (FDD)).

[0143] Furthermore, at least one of the above-described embodiments may be applied when the UE configures / activates / triggers specific information related to the above-described embodiment (or performs the operations of the above-described embodiment) through higher layer signaling / physical layer signaling. For example, the specific information may be any RRC parameter for a specific release (e.g., Rel. 18 / 19), etc.

[0144] If the UE does not support at least one of the specific UE capabilities or is not configured with the specific information, the UE may apply, for example, Rel. 15 / 16 behavior.

[0145] (Supplementary Notes) The following inventions are supplementary notes regarding one embodiment of the present disclosure. [Supplementary Note 1] A terminal having: a receiving unit that receives a setting indicating whether a serving cell can be a candidate cell for Layer 1 / Layer 2 (L1 / L2) inter-cell mobility; and a control unit that controls a switch of the serving cell based on the setting. [Supplementary Note 2] The terminal according to Supplementary Note 1, wherein the setting is a setting for each cell group indicating whether all the serving cells in a cell group can be the candidate cell for L1 / L2 inter-cell mobility. [Supplementary Note 3] The terminal according to Supplementary Note 1, wherein the setting is a setting indicating whether each serving cell in a cell group can be the candidate cell for L1 / L2 inter-cell mobility. [Supplementary Note 4] The terminal according to any one of Supplements 1 to 3, wherein the switch of the serving cell is a switching of the serving cell that is the candidate cell to a special cell (SpCell) or a secondary cell (SCell).

[0146] The following inventions are further appended to one embodiment of the present disclosure. [Supplementary Note 1] A terminal having: a receiver that receives a cell switch command for a special cell (SpCell) through Layer 1 / Layer 2 (L1 / L2) signaling; and a controller that makes different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell. [Supplementary Note 2] The terminal according to Supplementary Note 1, in which the controller assumes that the activation or deactivation status of the candidate cell will not change. [Supplementary Note 3] The terminal according to Supplementary Note 1 or Supplementary Note 2, in which the receiver receives an instruction to activate or deactivate the candidate cell. [Supplementary Note 4] The terminal according to any one of Supplements 1 to 3, in which the receiver receives an index associated with a part of a physical cell index (PCI) for a serving cell and a candidate cell in a cell group.

[0147] (Wireless Communication System) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0148] 13 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 (which may be simply referred to as 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).

[0149] 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.

[0150] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (Master Node (MN)), and the NR base station (gNB) is the secondary node (Secondary Node (SN)). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0151] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0152] 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.

[0153] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CCs) and dual connectivity (DC).

[0154] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

[0155] 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.

[0156] The multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with the Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0157] 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.

[0158] The core network 30 may include network functions (Network Functions (NF)) such as a User Plane Function (UPF), an Access and Mobility management Function (AMF), a Session Management Function (SMF), a Unified Data Management (UDM), an Application Function (AF), a Data Network (DN), a Location Management Function (LMF), and Operation, Administration and Maintenance (Management) (OAM). A single network node may provide multiple functions. Communication with an external network (e.g., the Internet) may also be performed via the DN.

[0159] The user terminal 20 may be a terminal that supports at least one of communication methods such as LTE, LTE-A, and 5G.

[0160] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the wireless communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0161] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (e.g., other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0162] 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.

[0163] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), or the like may be used as an uplink channel.

[0164] The PDSCH transmits user data, higher layer control information, a System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit a Master Information Block (MIB).

[0165] 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.

[0166] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as a UL grant, a UL DCI, etc. Note that the PDSCH may be replaced with DL data, and the PUSCH may be replaced with UL data.

[0167] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources for searching for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

[0168] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," "CORESET configuration," and the like in the present disclosure may be read interchangeably.

[0169] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0170] 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.

[0171] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

[0172] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as a reference signal.

[0173] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), or the like may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0174] 14 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.

[0175] 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.

[0176] 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.

[0177] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0178] 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.

[0179] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be configured from a transmitting unit and a receiving unit. The transmitting unit may be configured from a transmission processing unit 1211 and an RF unit 122. The receiving unit may be configured from a reception processing unit 1212, the RF unit 122, and a measurement unit 123.

[0180] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0181] 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.

[0182] The transceiver 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0183] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0184] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0185] The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

[0186] On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

[0187] 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.

[0188] 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.

[0189] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30 (e.g., network nodes that provide NF), other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0190] 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.

[0191] In addition, the transceiver 120 may transmit a configuration indicating whether the serving cell can be a candidate cell for Layer 1 / Layer 2 (L1 / L2) inter-cell mobility.

[0192] The control unit 110 may control the switch of the serving cell based on the setting.

[0193] The transceiver 120 may transmit a cell switch command for a special cell (SpCell) by Layer 1 / Layer 2 (L1 / L2) signaling.

[0194] The control unit 110 may perform different control on the activation or deactivation status of a candidate cell based on the type of the candidate cell.

[0195] (User Terminal) Fig. 15 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.

[0196] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0197] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on common understanding in the technical field to which the present disclosure relates.

[0198] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 220.

[0199] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0200] 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.

[0201] The transmitting / receiving antenna 230 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0202] 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.

[0203] The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0204] The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0205] The transmitter / receiver unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0206] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and if not, it may not be necessary to perform DFT processing as the transmission processing.

[0207] The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

[0208] On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

[0209] The transceiver unit 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0210] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0211] The transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving unit 220 and the transmitting / receiving antenna 230.

[0212] The transceiver 220 may receive a configuration indicating whether the serving cell can be a candidate cell for Layer 1 / Layer 2 (L1 / L2) inter-cell mobility.

[0213] The control unit 210 may control the switch of the serving cell based on the setting.

[0214] The setting may be a setting for each cell group indicating whether all the serving cells in the cell group can be the candidate cells for L1 / L2 inter-cell mobility.

[0215] The configuration may be a configuration indicating whether each serving cell in a cell group can be the candidate cell for L1 / L2 inter-cell mobility.

[0216] The switch of the serving cell may be a switch of the serving cell that is the candidate cell to a special cell (SpCell) or a secondary cell (SCell).

[0217] The transceiver 220 may receive a cell switch command for a special cell (SpCell) via Layer 1 / Layer 2 (L1 / L2) signaling.

[0218] The controller 210 may make different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell.

[0219] The control unit 210 may assume that the activation or deactivation status of the candidate cell remains unchanged.

[0220] The transceiver 220 may receive an indication of activation or deactivation of the candidate cell.

[0221] The transceiver 220 may receive indices associated with portions of physical cell indices (PCIs) for the serving cell and candidate cells in the cell group.

[0222] (Hardware Configuration) Note that the block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0223] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As described above, the implementation method of each is not particularly limited.

[0224] 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. 16 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.

[0225] In the present disclosure, the terms apparatus, circuit, device, section, unit, etc. may be used interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0226] 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.

[0227] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading specified software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0228] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transceiver unit 120 (220), etc. may be realized by the processor 1001.

[0229] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be implemented in a similar manner.

[0230] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EEPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, cache, main memory, etc. The memory 1002 may store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0231] Storage 1003 is a computer-readable recording medium and may be composed of at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0232] 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.

[0233] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0234] 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.

[0235] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using this hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0236] (Modifications) Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0237] 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.

[0238] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, Subcarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, specific filtering performed by a transceiver in the frequency domain, and specific windowing performed by a transceiver in the time domain.

[0239] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may also be a time unit based on numerology.

[0240] 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.

[0241] 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.

[0242] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

[0243] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0244] 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.

[0245] 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.

[0246] 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.

[0247] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0248] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0249] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI, each of which may be composed of one or more resource blocks.

[0250] In addition, one or more RBs may be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0251] 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.

[0252] A Bandwidth Part (BWP), which may also be referred to as a partial bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0253] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0254] 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."

[0255] 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.

[0256] 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.

[0257] 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.

[0258] 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.

[0259] 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.

[0260] 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.

[0261] The notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0262] Note that the physical layer signaling may be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be referred to as an RRC message, such as an RRC Connection Setup message or an RRC Connection Reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0263] 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).

[0264] 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).

[0265] 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.

[0266] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), these wired and / or wireless technologies are included within the definition of transmission media.

[0267] 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).

[0268] 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.

[0269] In the present disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0270] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication service within that coverage.

[0271] In the present disclosure, a base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control / operate based on the information.

[0272] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0273] 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.

[0274] 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. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

[0275] The mobile body is a movable object that can move at any speed and naturally includes cases where the mobile body is stationary. Examples of the mobile body include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects mounted thereon. The mobile body may also be a mobile body that moves autonomously based on an operation command.

[0276] 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). Note that 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.

[0277] 17 is a diagram showing an example of a vehicle according to an embodiment. The vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, an electronic control unit 49, various sensors (including a current sensor 50, an RPM sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

[0278] The drive unit 41 is configured with at least one of an engine, a motor, and a hybrid of an engine and a motor, for example. The steering unit 42 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by a user.

[0279] The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (for example, an input / output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

[0280] The signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the current of the motor, a rotation speed signal of the front wheels 46 / rear wheels 47 obtained by a rotation speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 obtained by an air pressure sensor 52, a vehicle speed signal obtained by a vehicle speed sensor 53, an acceleration signal obtained by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 obtained by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 obtained by a brake pedal sensor 56, an operation signal of the shift lever 45 obtained by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 58.

[0281] The information service unit 59 is composed of various devices, such as a car navigation system, an audio system, speakers, a display, a television, and a radio, for providing (outputting) various information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 59 uses information acquired from external devices via the communication module 60 or the like to provide various information / services (e.g., multimedia information / multimedia services) to the occupants of the vehicle 40.

[0282] The information service unit 59 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0283] The driving assistance system unit 64 includes various devices for providing functions to prevent accidents and reduce the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., Global Navigation Satellite System (GNSS)), map information (e.g., High Definition (HD) maps, Autonomous Vehicle (AV) maps), gyro systems (e.g., Inertial Measurement Units (IMUs), Inertial Navigation Systems (INSs)), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driving assistance functions or autonomous driving functions.

[0284] The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 to and from the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and the various sensors 50-58, which are provided in the vehicle 40.

[0285] The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the base station 10 or the user terminal 20 described above. Furthermore, the communication module 60 may be, for example, at least one of the base station 10 and the user terminal 20 described above (or may function as at least one of the base station 10 and the user terminal 20).

[0286] The communication module 60 may transmit at least one of signals from the above-mentioned various sensors 50-58 input to the electronic control unit 49, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 59 to an external device via wireless communication. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above-mentioned input.

[0287] The communication module 60 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from an external device and displays it on an information service unit 59 provided in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 60 (or data / information decoded from the PDSCH)).

[0288] Furthermore, the communication module 60 stores various information received from external devices in a memory 62 that can be used by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided in the vehicle 40.

[0289] 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 an uplink channel and a downlink channel may be read as a sidelink channel.

[0290] 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.

[0291] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc.), or a combination thereof.

[0292] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0293] Each aspect / embodiment described in the present disclosure may be a technology other than Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802. The present invention may be applied to systems that use IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable wireless communication methods, or to next-generation systems that are expanded, modified, created, or defined based on these. Furthermore, the present invention may be applied to a combination of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

[0294] 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."

[0295] 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.

[0296] 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.

[0297] 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.

[0298] Also, "determination" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "determination" may be considered to be "deciding" some action.

[0299] Furthermore, "judgment (decision)" may be read as "assuming," "expecting," "considering," or the like.

[0300] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0301] 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."

[0302] 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.

[0303] 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."

[0304] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0305] 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.

[0306] In the present disclosure, terms such as "less than or equal to," "less than," "greater than," "more than," "equal to," etc. may be interchangeable. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative, as expressions with "i-th" (i is an arbitrary integer) attached (for example, "highest" may be interchangeable with "i-th highest").

[0307] In this disclosure, the terms "of," "for," "regarding," "related to," "associated with," etc. may be read interchangeably.

[0308] 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.

[0309] This application is based on Japanese Patent Application No. 2022-166495, filed on October 17, 2022, the contents of which are incorporated herein in their entirety.

Claims

1. A receiver that receives a cell switch command for changing a serving cell by a Medium Access Control Element (MAC CE); a controller that makes different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell; The terminal, wherein the control unit assumes that the activation or deactivation status of the candidate cell is not changed.

2. The terminal described in claim 1, wherein the candidate cell is a cell set by Radio Resource Control (RRC) parameters.

3. The terminal described in claim 1, wherein the control unit assumes that the candidate cell after a cell switch based on the cell switch command is activated as an SpCell.

4. A method comprising: receiving a cell switch command for changing a serving cell by a Medium Access Control Element (MAC CE); making different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell; and assuming that the activation or deactivation status of the candidate cell remains unchanged.

5. A system including a terminal and a base station, The terminal a receiving unit that receives a cell switch command for changing a serving cell by a Medium Access Control Element (MAC CE); a controller that makes different assumptions about the activation or deactivation status of a candidate cell based on the type of the candidate cell; The control unit assumes that the activation or deactivation status of the candidate cell is not changed; The base station The system includes a transmitter that transmits the cell switch command.