Terminal, wireless communication method, and base station

Abstract

A terminal according to one embodiment of the present disclosure is characterized by being provided with: a reception unit that receives, from a candidate cell, a downlink control channel command to be used in triggering a random access procedure; and a control unit for determining the candidate cell associated with the serving cell on the basis of the downlink control channel command. According to one embodiment of the present disclosure, communication can be appropriately performed even when communication is performed using a plurality of transmission points.

Description

Technical Field

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

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

[0003] Research is also being conducted on subsequent systems of LTE (for example, also referred to as the 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 and later, etc.).

[0004] Prior Art Documents

[0005] Non-Patent Documents

[0006] Non-Patent Document 1: 3GPP TS 36.300 V8.12.0 "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)", April 2010 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] In future wireless communication systems (e.g., wireless communication systems after Rel.17 / 5G), it is envisioned to control communication that utilizes multiple transmit-receive points (e.g., multi-TRP (Multi-TRP (MTRP))) in a serving cell, or to control communication based on inter-cell mobility that includes non-serving cells.

[0009] In this case, it is also envisioned to control UL transmission (e.g., the implementation of a random access procedure (or the setting of a timing advance)) for each transmit-receive point, or for each serving cell and non-serving cell. However, it becomes a problem how a terminal (user terminal, User Equipment (UE)) controls UL transmission (e.g., timing advance control, etc.) for multiple transmit-receive points (or non-serving cells). If UL transmission to each transmit-receive point (or the TRP of a serving cell / non-serving cell) is not properly controlled, there is a concern that the quality of communication that utilizes multiple transmit-receive points may deteriorate.

[0010] The present disclosure has been made in view of this, and one of its purposes is to provide a terminal, a wireless communication method, and a base station that can appropriately perform communication even when communicating using multiple transmit-receive points.

[0011] Means for Solving the Problem

[0012] A terminal according to one aspect of the present disclosure is characterized by including: a receiving unit that receives a downlink control channel command used in triggering a random access procedure from a candidate cell; and a control unit that determines the candidate cell associated with a serving cell based on the downlink control channel command.

[0013] Advantageous Effects of the Invention

[0014] According to one aspect of the present disclosure, communication can be appropriately performed even when communicating using multiple transmit points. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figures 1A - 1D is a diagram showing an example of multi-TRP.

[0016] Figure 2A and Figure 2B is a diagram showing an example of inter-cell mobility.

[0017] Figure 3A and Figure 3B is a diagram showing an example of handover between a serving cell and an additional cell based on L1 / L2 signaling.

[0018] Figure 4 This is a diagram showing an example of Setting Examples 1-3 indicating the situation of supporting candidate cells.

[0019] Figures 5A - 5C This is a diagram showing an example of a situation where handover of a candidate cell / candidate cell group based on L1 / L2 signaling is performed in Setting Examples 1-3 of the situation of supporting candidate cells.

[0020] Figure 6 This is a diagram showing an example of the Timing Advance Group (TAG) to which the cells included in a cell group belong.

[0021] Figure 7 This is a diagram showing an example of a MAC CE for a Timing Advance Command.

[0022] Figure 8A and Figure 8B This is a diagram showing an example of the timing of PDCCH monitoring related to the first embodiment.

[0023] Figure 9 This is a diagram showing an example of the schematic structure of a radio communication system related to an embodiment.

[0024] Figure 10 This is a diagram showing an example of the structure of a base station related to an embodiment.

[0025] Figure 11 This is a diagram showing an example of the structure of a user terminal related to an embodiment.

[0026] Figure 12 This is a diagram showing an example of the hardware structure of a base station and a user terminal related to an embodiment.

[0027] Figure 13 This is a diagram showing an example of a vehicle related to an embodiment. Detailed Embodiments

[0028] (TCI, Spatial Relationship, QCL)

[0029] In NR, research is being conducted on controlling the reception processing (e.g., at least one of reception, demapping, demodulation, decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, coding) of at least one of a signal and a channel (expressed as signal / channel) in a UE based on the Transmission Configuration Indication state (TCI state).

[0030] The TCI state can also indicate the state of the signal / channel applied to the downlink. A state equivalent to the TCI state of the signal / channel applied to the uplink can also be expressed as a spatial relation.

[0031] The TCI state is information related to the Quasi-Co-Location (QCL) of the signal / channel, and can also be referred to as a spatial reception parameter, Spatial Relation Information, etc. The TCI state can also be set for the UE on a per-channel or per-signal basis.

[0032] QCL is an indicator representing the statistical properties of the signal / channel. For example, it can also mean that when a certain signal / channel has a QCL relationship with other signals / channels, it can be assumed that among these multiple different signals / channels, at least one of the Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same (being QCL for at least one of them).

[0033] In addition, the spatial reception parameter can also correspond to the receiving beam of the UE (e.g., the receiving analog beam), and the beam can also be determined based on spatial QCL. The QCL (or at least one element of QCL) in the present disclosure can also be rewritten as sQCL (spatial QCL).

[0034] Multiple types (QCL types) of QCL can also be defined. For example, four QCL types A - D can be set, and the parameters (or parameter sets) that can be assumed to be the same among these four QCL types A - D are different. Regarding this parameter (which can also be called the QCL parameter), it is expressed as follows:

[0035] · QCL type A (QCL-A): Doppler shift, Doppler spread, average delay, and delay spread;

[0036] · QCL type B (QCL-B): Doppler shift and Doppler spread;

[0037] · QCL type C (QCL-C): Doppler shift and average delay;

[0038] · QCL type D (QCL-D): spatial reception parameter.

[0039] The UE assumes that a certain control resource set (CORESET), channel, or reference signal has a specific QCL (e.g., QCL type D) relationship with other CORESETs, channels, or reference signals. This situation can also be referred to as a QCL assumption.

[0040] The UE can also determine at least one of the transmission beam (Tx beam) and the reception beam (Rx beam) of the signal / channel based on the TCI state or QCL assumption of the signal / channel.

[0041] The TCI state can also be, for example, information related to the QCL between the channel that is the object (in other words, the reference signal (RS) used for this channel) and other signals (e.g., other RSs). The TCI state can also be set (indicated) by higher-layer signaling, physical-layer signaling, or a combination thereof.

[0042] In addition, the channel / signal that is the application object of the TCI state can also be referred to as the target channel / reference signal (target channel / RS), and can also be abbreviated as the target. The above-mentioned other signals can also be referred to as reference reference signals (reference RS), source RS (source RS), and can also be abbreviated as references, etc.

[0043] The channel for which the TCI state or spatial relationship is set (specified) can also be, for example, at least one of a downlink shared channel (Physical Downlink Shared Channel (PDSCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), and an uplink control channel (Physical Uplink Control Channel (PUCCH)).

[0044] In addition, the RS that forms a QCL relationship with the channel may also be at least one of, for example, a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), a reference signal for measurement (Sounding Reference Signal (SRS)), a CSI-RS for tracking (also referred to as a Tracking Reference Signal (TRS)), a reference signal for QCL detection (also referred to as a QRS), a DeModulation Reference Signal (DMRS), etc.

[0045] The SSB is a signal block that includes at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a broadcast channel (Physical Broadcast Channel (PBCH)). The SSB may also be referred to as an SS / PBCH block.

[0046] The RS of QCL type X in the TCI state may also mean an RS that has a QCL type X relationship with a certain channel / signal (DMRS thereof), and this RS may also be referred to as the QCL source of QCL type X in this TCI state.

[0047] (Initial access procedure)

[0048] During the initial access procedure, the UE (in RRC_IDLE mode) performs reception of the SS / PBCH block (SSB), transmission of Msg.1 (PRACH / random access preamble / preamble), reception of Msg.2 (PDCCH, PDSCH including a random access response (RAR)), transmission of Msg.3 (PUSCH scheduled by the RAR UL grant), and reception of Msg.4 (PDCCH, PDSCH including a UE contention resolution identity). After that, an ACK for Msg.4 is sent from the UE to the base station (network), and an RRC connection (RRC_CONNECTED mode) is established.

[0049] The reception of SSB includes PSS detection, SSS detection, PBCH-DMRS detection, and PBCH reception. PSS detection performs detection of a part of the physical cell ID (PCI), detection of OFDM symbol timing (synchronization), and (coarse) frequency synchronization. SSS detection includes detection of the physical cell ID. PBCH-DMRS detection includes detection of a part of the SSB index within a semi-wireless frame (5 ms). PBCH reception includes detection of the system frame number (SFN) and radio frame timing (SSB index), reception of the setting information for receiving the remaining minimum system information (RMSI, SIB1), and identification of whether the UE can camp on this cell (carrier).

[0050] SSB has a bandwidth of 20 RBs and a time of 4 symbols. The transmission period of SSB can be set from {5, 10, 20, 40, 80, 160} ms. In a half-frame, multiple symbol positions of SSB are specified based on the frequency range (FR1, FR2).

[0051] PBCH has a payload of 56 bits. N repetitions of PBCH are transmitted within a period of 80 ms. N depends on the SSB transmission period.

[0052] System information consists of the MIB carried by PBCH, RMSI (SIB1), and other system information (OSI). SIB1 includes RACH settings and information for performing the RACH procedure. The time / frequency resource relationship between SSB and the PDCCH monitoring resources for SIB1 is set through PBCH.

[0053] The base station using beam correspondence uses multiple beams to separately transmit multiple SSBs for each SSB transmission period. Each of the multiple SSBs has multiple SSB indexes. The UE that detects one SSB transmits a PRACH in the RACH opportunity associated with this SSB index and receives a RAR in the RAR window.

[0054] (Multi-TRP)

[0055] In NR, research is being conducted on using one or more transmission / reception points (TRP) (multi-TRP) with one or more panels (multi-panel) to perform DL transmission to the UE. In addition, research is being conducted on the UE performing UL transmission to one or more TRPs.

[0056] In addition, multiple TRPs can correspond to the same cell identifier (cell Identifier (ID)), or can also correspond to different cell IDs. This cell ID can be either a physical cell ID (e.g., PCI), or a virtual cell ID.

[0057] Figures 1A - 1D FIG. is an example diagram showing a multi-TRP scenario. In these examples, it is assumed that each TRP can transmit 4 different beams, but it is not limited thereto.

[0058] Figure 1A FIG. shows an example of a case where only one TRP (TRP1 in this example) among multiple TRPs transmits to the UE (which can also be referred to as single mode, single TRP, etc.). In this case, TRP1 transmits both a control signal (PDCCH) and a data signal (PDSCH) to the UE.

[0059] In the present disclosure, the single-TRP mode can also mean a mode in which multiple TRPs (modes) are not set.

[0060] Figure 1B FIG. shows an example of a case where only one TRP (TRP1 in this example) among multiple TRPs transmits a control signal to the UE, and the multiple TRPs transmit data signals (which can also be referred to as single-master mode). The UE receives each PDSCH transmitted from the multiple TRPs based on one downlink control information (Downlink Control Information (DCI)).

[0061] Figure 1C FIG. shows an example of a case where each of the multiple TRPs transmits a part of the control signal to the UE, and the multiple TRPs transmit data signals (which can also be referred to as master-slave mode). It can also be that part 1 of the control signal (DCI) is transmitted in TRP1, and part 2 of the control signal (DCI) is transmitted in TRP2. Part 2 of the control signal can also depend on part 1. The UE receives each PDSCH transmitted from the multiple TRPs based on these parts of the DCI.

[0062] Figure 1D FIG. shows an example of a case where each of the multiple TRPs transmits different control signals to the UE, and the multiple TRPs transmit data signals (which can also be referred to as multi-master mode). It can also be that the first control signal (DCI) is transmitted in TRP1, and the second control signal (DCI) is transmitted in TRP2. The UE receives each PDSCH transmitted from the multiple TRPs based on these DCIs.

[0063] In Figure 1BIn the case of using one DCI to schedule multiple PDSCHs from multiple TRPs (which can also be referred to as multiple PDSCHs), this DCI can also be referred to as a single DCI (S-DCI, single PDCCH). In addition, in Figure 1D In the case of using multiple DCIs to separately schedule multiple PDSCHs from multiple TRPs, these multiple DCIs can also be referred to as multiple DCIs (M-DCI, multiple PDCCHs).

[0064] Each TRP of the multiple TRPs can send different transport blocks (TBs) / codewords (CWs) / different layers. Alternatively, each TRP of the multiple TRPs can also send the same TB / CW / layer.

[0065] As a way of transmission by multiple TRPs, non-coherent joint transmission (NCJT) is being studied. In NCJT, for example, TRP1 modulates and maps the first codeword, performs layer mapping, and uses the first precoding for the first number of layers (e.g., 2 layers) to send the first PDSCH. In addition, TRP2 modulates and maps the second codeword, performs layer mapping, and uses the second precoding for the second number of layers (e.g., 2 layers) to send the second PDSCH.

[0066] In addition, multiple PDSCHs (multi-PDSCHs) of NCJT can also be defined as partially or completely overlapping with respect to at least one of the time domain and the frequency domain. That is, at least one of the time and frequency resources of the first PDSCH from the first TRP and the second PDSCH from the second TRP can also overlap.

[0067] It can also be conceived that these first PDSCH and second PDSCH are not in a quasi-co-location (QCL) relationship (not quasi-co-located). The reception of multi-PDSCH can also be rewritten as the simultaneous reception of a PDSCH of a non-QCL type (e.g., QCL type D).

[0068] It is being studied to support the repetition of PDSCH (transport block (TB) or codeword (CW)) across multiple TRPs in the URLLC of multiple TRPs. It is being studied to support the repetition method across multiple TRPs in the frequency domain or layer (space) domain or time domain (URLLC schemes, for example, Scheme 1, 2a, 2b, 3, 4). In Scheme 1, multiple PDSCHs from multiple TRPs are subjected to space division multiplexing (SDM). In Schemes 2a and 2b, the PDSCHs from multiple TRPs are subjected to frequency division multiplexing (FDM). In Scheme 2a, the redundancy version (RV) is the same for multiple TRPs. In Scheme 2b, the RV for multiple TRPs can be either the same or different. In Schemes 3 and 4, multiple PDSCHs from multiple TRPs are subjected to time division multiplexing (TDM). In Scheme 3, multiple PDSCHs from multiple TRPs are sent within one time slot. In Scheme 4, multiple PDSCHs from multiple TRPs are sent in different time slots.

[0069] According to such a multiple TRP scenario, more flexible transmission control using a good-quality channel can be performed.

[0070] NCJT using multiple TRPs / panels has the potential to use a high rank. To support ideal and non-ideal backhaul between multiple TRPs, single DCI (single PDCCH, for example, Figure 1B ) and multi-DCI (multi-PDCCH, for example, Figure 1D ) can also be supported. For both single DCI and multi-DCI, the maximum number of TRPs can also be 2.

[0071] Regarding the single PDCCH design (mainly for ideal backhaul), the extension of TCI is being studied. Each TCI code point in the DCI can also correspond to one or two TCI states. The TCI field size can also be the same as the TCI field size in Rel.15.

[0072] For the PDCCH / CORESET specified in Rel.15, one TCI state without a CORESET pool index (CORESETPoolIndex) (which can also be referred to as TRP information (TRP Info)) can also be set for one CORESET.

[0073] For the enhancement of PDCCH / CORESET specified in Rel.16, in multi-TRP based on multi-DCI, a CORESET pool index is set for each CORESET.

[0074] (Inter-cell mobility)

[0075] In NR, one or more Transmission / Reception Points (TRPs) (Multi-TRP (MTRP)) are being studied for DL transmission to a UE. In addition, UL transmission from a UE to one or more TRPs is being studied.

[0076] Consider a UE receiving channels / signals from multiple cells / TRPs during inter-cell mobility (e.g., L1 / L2 inter-cell mobility) (see Figure 2A , B).

[0077] Figure 2A This shows an example of inter-cell mobility including a non-serving cell (e.g., Single-TRP inter-cell mobility). One TRP (or, single TRP) can also be set for a UE in each cell. Here, it shows the case where a UE receives channels / signals from the base station / TRP of cell #1 which is the serving cell and the base station / TRP of cell #3 which is not the serving cell (becomes a non-serving cell / Non-serving cell). For example, it corresponds to the case where a UE switches from cell #1 to cell #3 (e.g., fast cell switch).

[0078] In this case, the selection of ports (e.g., antenna ports) / TRPs can also be performed dynamically. The selection of ports (e.g., antenna ports) / TRPs can also be performed based on the TCI state indicated or updated by DCI / MAC CE. Here, it shows the case where different physical cell IDs (e.g., PCI) are supported for cell #1 and cell #3.

[0079] Figure 2BThis represents an example of a multi-TRP scenario (e.g., inter-cell mobility in the case of using multi-TRP). Multiple (e.g., two) TRPs (or different CORESET pool indices) can also be set for the UE in each cell. Here, it shows the case where the UE receives channels / signals from TRP#1 and TRP2. In addition, here, it shows the case where TRP#1 corresponds to physical cell ID (PCI) #1 and TRP#2 corresponds to PCI #2.

[0080] The multi-TRPs (TRP#1, #2) are connected through ideal / non-ideal backhaul, and information, data, etc. can also be exchanged. From each TRP of the multi-TRPs, the same or different codewords (Code Word (CW)) and the same or different layers can also be sent respectively. As a way of multi-TRP transmission, as Figure 2B shown, Non-Coherent Joint Transmission (NCJT) can also be used. Here, it shows the case of performing NCJT between TPRs corresponding to different PCIs. In addition, the same serving cell setting can also be applied / set for TRP#1 and TRP#2.

[0081] Multiple PDSCHs (multi-PDSCHs) subjected to NCJT can also be defined as partially or completely overlapping with respect to at least one of the time domain and the frequency domain. That is, at least one of the time and frequency resources of the first PDSCH from TRP#1 and the second PDSCH from TRP#2 can also overlap. The first PDSCH and the second PDSCH can be used for the transmission of the same TB or different TBs.

[0082] It can also be envisioned that these first PDSCH and second PDSCH are not in a Quasi-Co-Location (QCL) relationship (not quasi-co-located). The reception of the multi-PDSCH can also be rewritten as the simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

[0083] Multiple PDSCHs (which can also be referred to as multiple PDSCH) from multi-TRPs can also be scheduled (single master mode) using one DCI (single DCI (S-DCI), single PDCCH). One DCI can also be sent from one TRP of the multi-TRPs. The structure of using one DCI in multi-TRPs can also be referred to as multi-TRP based on single DCI (mTRP / MTRP).

[0084] Multiple PDSCHs from multiple TRPs can also be separately scheduled (multi-primary mode) using multiple DCIs (multi-DCI, multiple PDCCH). Multiple DCIs can also be separately transmitted from multiple TRPs. The structure using multiple DCIs in multiple TRPs can also be referred to as multi-TRP based on multi-DCI (mTRP / MTRP).

[0085] The UE can also be conceived as sending a separate CSI report (CSI report) related to each TRP for different TRP transmissions. Such CSI feedback can also be referred to as separate feedback, separate CSI feedback, etc. In the present disclosure, "separate" can also be rewritten as "independent".

[0086] In inter-cell mobility, consider the following scenario 1 or scenario 2. Additionally, in the present disclosure, the serving cell can also be rewritten as the TRP within the serving cell. Layer 1 / layer 2 (L1 / L2), DCI / Medium Access Control Control Element (MAC CE) can also be rewritten with each other. In the present disclosure, the PCI different from the physical cell ID (PCI) of the current serving cell is sometimes simply referred to as "different PCI". The non-serving cell, the cell with a different PCI, and the additional cell can also be rewritten with each other.

[0087] <Scenario 1>

[0088] Scenario 1 corresponds to, for example, inter-cell mobility of multiple TRPs. Additionally, scenario 1 can also be a scenario of inter-cell mobility that does not correspond to multiple TRPs. In scenario 1, for example, the following processes are performed.

[0089] (1) The UE receives from the serving cell the setting of the SSB for beam measurement of the TRP corresponding to the PCI different from that of the serving cell, and the setting required for using radio resources for data transmission and reception, including the resources with different PCI.

[0090] (2) The UE performs beam measurement of the TRP corresponding to the different PCI and reports the beam measurement result to the serving cell.

[0091] (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.

[0092] (4) The UE transmits and receives using UE-dedicated channels on TRPs corresponding to different PCIs.

[0093] (5) The UE needs to always be covered by the serving cell, including the case of multiple TRPs. Similar to the existing system, the UE needs to use common channels (Broadcast Control Channel (BCCH), Paging Channel (PCH), etc.) from the serving cell.

[0094] In Scenario 1, when the UE transmits and receives signals with an additional cell / TRP (the TRP corresponding to the PCI of the additional cell), the serving cell (as envisioned by the serving cell in the UE) is not changed. That is, L1 / L2-based serving cell handover is not supported. The UE is set with high-layer parameters associated with the PCI of a non-serving cell from the serving cell. Scenario 1 can also be applied, for example, in Rel. 17.

[0095] Figure 3A It is a diagram showing an example of the movement of a UE in Rel. 17. Envision a case where the UE moves from a cell with PCI #1 (serving cell) to a cell with PCI #3 (additional cell) (overlapping with the serving cell). In this case, in Rel. 17, L1 / L2-based serving cell handover is not supported.

[0096] The additional cell is a cell with an additional PCI different from the PCI of the serving cell. The UE can receive / send UE-dedicated channels from the additional cell. The UE needs to be within the coverage area of the serving cell to receive UE common channels (e.g., system information / paging / short message). In the case where the UE moves outside the coverage area of the serving cell, cell handover needs to be performed through handover (also called L3 mobility), etc.

[0097] <Scenario 2>

[0098] In Scenario 2, L1 / L2 inter-cell mobility is applied. In L1 / L2 inter-cell mobility, functions such as beam control can be used to change the serving cell without performing RRC reconfiguration. In other words, transmission and reception with the additional cell can be performed without handover (or without the L3 mobility process). Since handover requires RRC reconnection, etc., which results in a non-data communication period, by applying L1 / L2 inter-cell mobility without handover, data communication can continue even when the serving cell changes. In Scenario 2, for example, the following steps are performed.

[0099] (1) The UE receives the setting of the SSB of a cell (additional cell) with a different PCI from the serving cell for beam measurement / change of the serving cell.

[0100] (2) The UE performs beam measurement of cells with different PCIs and reports the measurement results to the serving cell.

[0101] (3) The UE can also receive the setting of a cell with a different PCI (serving cell setting) through higher layer signaling (e.g., RRC). That is, prior setting related to the change of the serving cell can also be performed. This setting can be performed either together with the setting in (1) or separately.

[0102] (4) Based on the above report, the TCI state of a cell with a different PCI can also be activated through L1 / L2 signaling according to the change of the serving cell. The activation of the TCI state and the change of the serving cell can also be performed separately.

[0103] (5) The UE changes the serving cell (assumption of the serving cell) and starts receiving / sending using the UE-specific channels and TCI state that are pre-set.

[0104] That is, in Scenario 2, the serving cell (assumption of the serving cell in the UE) is updated through L1 / L2 signaling. Scenario 2 can also be applied after Rel.18.

[0105] Figure 3B It is a diagram showing an example of the movement of the UE in Rel.18. In Rel.18, the serving cell is switched through L1 / L2. The UE can receive / send UE-specific channels / common channels with the new serving cell. The UE can also move out of the coverage area of the previous serving cell.

[0106] (Setting of candidate cells)

[0107] In L1 / L2 inter-cell mobility, candidate cells can also be set in addition to the serving cell. In the present disclosure, candidate cells can also be rewritten as target cells, additional cells, additional PCIs. One or more candidate cells (or, a group of candidate cells) can be associated with each serving cell separately, or one or more candidate cells (or, a group of candidate cells) can be associated with multiple serving cells commonly.

[0108] The setting of a candidate cell (or, a candidate cell group) can also be configured using specific higher layer parameters (e.g., ServingCellConfig), in the same way as the inter-cell beam management in existing systems (e.g., prior to Rel.17). Alternatively, for the setting of a candidate cell (or, a candidate cell group), the framework of carrier aggregation configuration (e.g., CA configuration framework), or the framework of CHO (Conditional Handover) / CPC (Conditional PSCell Change) setting can also be reused.

[0109] For a candidate cell (or, a candidate cell group) configured by higher layer parameters, the UE can also be signaled its activation / deactivation via MAC CE / DCI.

[0110] As the setting of a candidate cell (or, the association with the serving cell), for example, at least one of the following Setting Example 1 to Setting Example 3 can also be applied. Here, as the serving cells, SpCell#0, SCell#1, and SCell#2 are configured, and an example of a candidate cell / candidate cell group configured separately from the serving cells is shown. The following Setting Example 1 to Setting Example 3 are just examples, and the number of serving cells / number of candidate cells / number of candidate cell groups, the association between the serving cell and the candidate cell, etc. are not limited thereto and can be appropriately changed. Alternatively, in addition to or instead of Setting Example 1 to Setting Example 3, other setting examples can also be supported / applied.

[0111] [Setting Example 1]

[0112] Setting Example 1 is as follows: For each serving cell (or, the frequency domain corresponding to each serving cell separately), one or more candidate cells are associated / configured (see Figure 4 ). Here, it shows the following situation: Candidate cells #0-1, #0-2, and #0-3 are associated with SpCell#0 (or the frequency domain corresponding to SpCell#0), candidate cell #1-1 is associated with SCell#1 (or the frequency domain corresponding to SCell#1), and candidate cells #2-1 and #2- are associated with SCell#2 (or the frequency domain corresponding to SpCell#2). The information related to this association can also be configured / signaled from the base station to the UE via RRC / MAC CE / DCI.

[0113] [Setting Example 2]

[0114] Setting Example 2 is as follows: For a MAC entity / MCG / SCG, candidate cells are associated / configured (see Figure 4). Here, a case is shown where candidate cells #3 - #8 are associated with the MAC entity / MCG / SCG. In this case, instead of candidate cells being associated with each serving cell, candidate cells are set for the MAC entity or cell group (e.g., MCG / SCG). Information related to the candidate cells set for each cell can also be set / indicated to the UE from the base station via RRC / MAC CE / DCI.

[0115] [Setting Example 3]

[0116] In Setting Example 3, one or more candidate cell groups are set (refer to Figure 4 ). A candidate cell group has one or more candidate cells. Here, a case is shown where candidate cell group #1 with candidate cells #0 - #2, candidate cell group #2 with candidate cells #0, #1, and candidate cell group #3 with candidate cell #0 are set. At least one of the information related to the set candidate cell group and the information related to the candidate cells included in each candidate cell group can also be set / indicated to the UE from the base station via RRC / MACCE / DCI.

[0117] [Serving Cell Handover]

[0118] In existing systems (e.g., Rel.17), L1 beam indication related to the additional PCI (or, additional cell) TCI state is supported (e.g., indication based on the TCI state field of DCI).

[0119] After Rel.18, it is envisioned to support new L1 / L2 signals (e.g., DCI / MAC CE) for indicating the handover of the serving cell (e.g., serving cell switch). As this indication, it is also envisioned to support at least one of implicit indication and explicit indication. Implicit indication can also mean, for example, that a certain CORESET is updated to the TCI state associated with the additional PCI via MAC CE. Explicit indication can also mean that the handover of the cell is directly indicated via DCI / MAC CE.

[0120] For example, in Setting Example 1 of candidate cells, a specific candidate cell can also be designated as the serving cell (or, indicated for handover to the serving cell) via L1 / L2 signaling. In Figure 5A a case is shown where candidate cells #0 - 2 become the SpCell of the MCG / SCG (SpCell#0 and candidate cells #0 - 2 are switched) via L1 / L2 signaling. In addition, a case is shown where candidate cells #2 - 1 become the SCell of the MCG / SCG (SCell#2 and candidate cells #2 - 1 are switched) via L1 / L2 signaling.

[0121] Alternatively, in the second example of candidate cell configuration, a specific candidate cell may also be designated as a serving cell via L1 / L2 signaling (or, instructed to hand over to the serving cell). In Figure 5B it shows a case where candidate cell #4 becomes the SpCell of the MCG / SCG via L1 / L2 signaling (SpCell#0 and candidate cell #4 are handed over).

[0122] Alternatively, in the third example of candidate cell configuration, a specific group of candidate cells (or, one or more candidate cells included in the specific group of candidate cells) may also be changed / updated to a group of serving cells via L1 / L2 signaling. In Figure 5C it shows a case where candidate cell group #1 (or, candidate cells #0 - #2 included in candidate cell group #1) becomes a group of serving cells via L1 / L2 signaling (the group of serving cells and candidate cell group #1 are handed over). Among the candidate cells included in candidate cell group #1 (here candidate cells #0 - #2), the candidate cell associated with SpCell#0 or the candidate cell set in the same frequency domain as SpCell#0 (here candidate cell #0) may also be set as the new SpCell. Alternatively, the candidate cell that becomes the SpCell may also be instructed via L1 / L2 signaling.

[0123] (Timing Advance Group)

[0124] When multiple TRPs are used, there may also be a situation where the distances between the UE and each TRP are different. Multiple TRPs may also be included in the same cell (e.g., serving cell). Alternatively, it may be that one of the multiple TRPs corresponds to the serving cell and the other TRPs correspond to non - serving cells. In this case, it is also assumed that the distances between each TRP and the UE are different.

[0125] In the existing system, the transmission timing of the UL (Uplink) channel and / or UL signal (UL channel / signal) is adjusted by timing advance (TA: Timing Advance). The reception timing of the UL channel / signal from different user terminals (UE: User Terminal) is adjusted on the side of the radio base station (also referred to as TRP: Transmission and Reception Point, gNB: gNodeB, etc.).

[0126] The UE may also apply timing advance (multiple timing advance) for each pre - set timing advance group (TAG: Timing Advance Group) to perform timing control of UL transmission.

[0127] In the case of applying multiple timing advances, it is supported to send timing advance groups (TAGs: Timing Advance Group) classified by timing. The UE assumes that the same TA offset (or TA value) is applied for each TAG to control the UL transmission timing in each TAG. That is, the TA offset can also be set independently for each TAG.

[0128] In the case of applying multiple timing advances, the UE can align the uplink signal reception timing from the UE at the radio base station even when using multiple cells by independently adjusting the transmission timing of the cells belonging to each TAG.

[0129] TAGs (for example, serving cells belonging to the same TAG) can also be set by higher layer parameters. The same timing advance value can also be applied to serving cells belonging to the same TAG. It can also be that the timing advance group of the SpCell containing the MAC entity is called the primary timing advance group (PTAG), and other TAGs are called secondary timing advance groups (STAGs).

[0130] In the existing system (for example, Rel.16 NR), each cell group (for example, MCG / SCG) supports setting a maximum of 4 TAGs (refer to Figure 6 ). In Figure 6 , it shows the case where 3 TAGs are set for a cell group including the SpCell and SCell#1~#4. Here, it shows the following case: the SpCell and SCell#1 belong to the first TAG (PTAG or TAG#0), SCell#2 and SCell#3 belong to the second TAG (TAG#1), and SCell#4 belongs to the third TAG (TAG#2).

[0131] The timing advance command (TA command) can also be notified to the UE using a MAC control element (for example, MAC CE). The TA command is a command indicating the transmission timing value of the uplink channel and is included in the MAC control element. The TA command is signaled from the radio base station to the UE at the MAC layer. The UE controls a specific timer (for example, TA timer) based on the reception of the TA command.

[0132] The MAC CE for the timing advance command (TAC MAC CE) can also be a structure including a field for the timing advance group index (for example, TAGID) and a field for the timing advance command (refer to Figure 7 ).

[0133] On the other hand, consider a scenario in a future wireless communication system where different TAGs (or TAG-IDs) are set for more than one TRP corresponding to a certain cell (or CC). For example, in the case of multi-TRP operation using multiple DCIs, it is envisaged to support two TAs (or TAGs) in UL transmission.

[0134] Alternatively, it is also envisaged that different TRPs corresponding to a certain cell share a common TAG. Or, it is also envisaged that the MAC CE for TA command is applied to only one TRP, or the MAC CE for TA command is applied to multiple TRPs.

[0135] Or, it is also envisaged that TRPs corresponding to different cells respectively use different TAGs / share a common TAG. For example, in inter-cell mobility, it is also envisaged to control UL transmission based on common / different timing advance for the serving cell (or the TRP of the serving cell) and the non-serving cell (or the TRP of the non-serving cell).

[0136] Thus, in MIMO after Rel.18, in multi-TRP operation using multiple DCIs, it is also envisaged to support two timing advances (TAs) for two TRPs.

[0137] In the case where the TAG is set / controlled on a per-TRP basis, the time alignment timer (e.g., timeAlignmentTimer) can also be set per TRP. The time alignment timer can also control the time when the MAC entity considers that the serving cell to which the associated TAG belongs is uplink time aligned (e.g., uplink time aligned). For example, in order to maintain (e.g., maintenance) UL time alignment, the time alignment timer can also be set via RRC.

[0138] The time alignment timer (e.g., timeAlignementTimer) can also be maintained for UL time alignment. In Rel.17, the time alignment timer (e.g., timeAlignementTimer) corresponds per TAG. When the UE receives the MAC CE for the timing advance command (e.g., TAC MAC CE), it starts or restarts the time alignment timer associated with the indicated timing advance group (e.g., TAG) respectively.

[0139] The MAC entity maintains a specific value (N) when receiving the TAC MAC CE and between the indicated TAGs TAIn the case of ), apply the timing advance command for the indicated TAG, or start or restart the timing alignment timer associated with the indicated TAG. A specific value (N TA ) can also be the timing advance between DL and UL.

[0140] The operations in the case where the timing alignment timer expires can also be separately defined in the PTAG and STAG, respectively. Additionally, the timing advance group (TAG) including the SpCell of the MAC entity can be referred to as the primary timing advance group (PTAG), and the TAGs other than this can be referred to as the secondary timing advance groups (STAG).

[0141] For example, in Rel.17, it is also possible to support: applying a specific operation for the PTAG in the case where the timing advance timer corresponding to the PTAG expires, and applying a specific operation for the STAG in the case where the timing advance timer corresponding to the STAG expires.

[0142] For example, in the case where the timing alignment timer expires, the following operations (for example, a specific operation for the PTAG / a specific operation for the STAG) can also be performed.

[0143] [Specific operation for the PTAG]

[0144] In the case where the timing alignment timer is associated with the PTAG,

[0145] · Flush (discard) all HARQ buffers of all serving cells.

[0146] · If set, notify the RRC to release the PUCCH for all serving cells.

[0147] · If set, notify the RRC to release the SRS.

[0148] · Clear all the set DL allocations and all the set UL allocations.

[0149] · Clear the PUSCH resources for semi-persistent CSI reporting.

[0150] · Cause all the running timing alignment timers to expire.

[0151] · Maintain N for all TAGs TA .

[0152] [Specific operation for the STAG]

[0153] In the case where the timing alignment timer is associated with the STAG, for all serving cells belonging to that TAG,

[0154] · Refresh (discard) all HARQ buffers.

[0155] · If set, notify RRC to release PUCCH.

[0156] · If set, notify RRC to release SRS.

[0157] · Clear all configured DL allocations and UL allocations.

[0158] · Clear the PUSCH resources for semi-persistent CSI reporting.

[0159] · Maintain the N of this TAG TA 。

[0160] (TA control per TRP / panel)

[0161] As described above, in the case of communication using multiple transmit-receive points (e.g., TRPs) / panels, it is also envisaged to control the timing advance (TA) per TRP / per panel.

[0162] In NR after Rel.18, for RACH triggered by PDCCH order and RACH triggered by UE, contention-based random access (CBRA) / contention-free random access (CFRA) is considered / decided in units of TRP or TRP TA (TA per TRP).

[0163] In the case of applications / configurations that support timing advance per TRP (or in units of TRP), the UE controls UL transmissions (e.g., RACH transmissions, etc.) in each TRP based on the timing advance corresponding to each TRP (or the timing advance group to which each TRP belongs).

[0164] Information related to the TRP corresponding to each serving cell (e.g., TRP index / TRP ID) can also be configured / indicated to the UE by the base station using RRC / MAC CE / downlink control information. The UE can also receive association information related to the timing advance corresponding to each TRP (e.g., information related to TA value / timing advance command / time alignment timer, etc.) from the base station.

[0165] Each embodiment of the present disclosure can also be applied / supported in at least one of intra-cell multi-TRP (Intra-cell M-TRP) and inter-cell multi-TRP (Inter-cell M-TRP).

[0166] In multi-TRP within a cell, multiple TRPs (or, the activated TCI states of multiple TRPs) can also be associated with the same cell ID. The cell ID can also be a Physical Cell ID (PCI).

[0167] In multi-TRP between cells, multiple TRPs (or, the activated TCI states of multiple TRPs) can also be associated with different cell IDs (e.g., PCI). For example, in multi-TRP between cells, two TRPs can also be rewritten as two TRPs respectively associated with two PCIs.

[0168] In the case of supporting the application / setting of timing advance per TRP (or, in units of TRP), each TRP can also belong to a different TAG. Multiple TRPs of a serving cell (e.g., two TRPs) can also belong to two different TAGs respectively. A TAG can also include multiple TRPs from multiple serving cells. All TRPs / serving cells within a TAG apply / maintain the same timing advance (TA) / the same time alignment timer.

[0169] In the present disclosure, a TAG can also include more than one sub-TAG. For example, two TRPs of a serving cell belong to two different sub-TAGs respectively and also belong to one TAG. A sub-TAG can also include multiple TRPs from multiple serving cells. All TRPs / serving cells within a sub-TAG apply / maintain the same timing advance (TA) / the same time alignment timer.

[0170] For example, TA can also be applied separately per TRP (or, be indicated in units of TRP TA). For example, at least one of the following options can also be applied.

[0171] [Option 1]

[0172] Different TAG-IDs can also be set per TRP, and different MAC CEs for TA commands can be set per TRP. Each TAG can also maintain a time alignment timer for UL time alignment.

[0173] [Option 2]

[0174] Different TRPs can also share a TAG. The MAC CE for TA commands can also be applied to only one TRP. The UE can also apply different TAs to other TRPs. For example, the UE can adjust the TA value for other TRPs (e.g., TRP#1) through a TA offset (TA_TRP_offset) based on the TA used for TRP#0 (TA_TRP#0).

[0175] In this case, there can also be only one timing alignment timer for UL timing alignment of multiple TRPs. This means that the UL timing alignment of multiple TRPs is maintained or lost simultaneously.

[0176] [Option 3]

[0177] The TAG can also be set to one. The TA command using MAC CE can also be applied to multiple serving TRPs for the UE.

[0178] [Option 4]

[0179] The TAG can also be set to one. The TA command received through the TRP / CW / PDSCH / DMRS port group using MAC CE can also be applied to the same TRP / CW / PDSCH / DMRS port group of the TAG. Each TRP / CW / PDSCH / DMRS port group of the TAG can also maintain a timing alignment timer for UL timing alignment.

[0180] Thus, after Rel.18, it is also envisioned to support multiple timing advances in multi-TRP (e.g., multi-TRP using multi-DCI). For example, for a multi-TRP using multi-DCI (e.g., two TRPs), multiple (e.g., 2) timing advances can also be supported. In addition, the application of multiple timing advances for multi-TRP can be supported both in the intra-cell / inter-cell multi-DCI multi-TRP scenario and in multiple frequency ranges (e.g., FR1 and FR2).

[0181] (PDCCH command (order))

[0182] DCI format 1_0 contains an identifier field of the DCI format, a bit field that is always set to 1, and a frequency domain resource assignment field. When the cyclic redundancy check (CRC) of DCI format 1_0 is scrambled by C-RNTI and all fields of the frequency domain resource assignment field are 1, this DCI format 1_0 is used for the random access procedure started according to the PDCCH command, and the remaining fields are the random access preamble, UL / supplementary uplink (SUL) indicator, SS / PBCH index (SSB index), PRACH mask index, and reserved bits (12 bits).

[0183] In the case of PRACH transmission triggered by a PDCCH command, the PRACH mask index field indicates that, when the value of the random access preamble index field is not zero, the PRACH opportunity is the PRACH opportunity for the PRACH transmission associated with the SS / PBCH block index shown by the SS / PBCH block index field of the PDCCH command.

[0184] (RACH procedure triggered by PDCCH command)

[0185] In an existing system (e.g., prior to Rel. 17), regarding the RACH procedure for a specific cell (e.g., SpCell), for RACH by a PDCCH command, the UE assumes that the PDCCH command and the PDCCH for the RAR have the same QCL characteristics, and thus performs the RACH procedure. The PDCCH for the RAR can also be a PDCCH transmitted by the base station in response to the PRACH triggered (or sent from the UE) by the PDCCH command to the UE. The PDSCH scheduled by this PDCCH for the RAR may also include the RAR. The QCL characteristics can also be rewritten as DMRS QCL characteristics.

[0186] Specifically, when the UE starts PRACH transmission in response to a PDCCH command for triggering the CFRA procedure for the SpCell and performs detection of DCI format 1_0 scrambled by CRC with the corresponding RA-RNTI, the UE can also assume that the PDCCH containing DCI format 1_0 and the PDCCH command have the same DMRS antenna port quasi-co-location characteristics.

[0187] In addition, in an existing system (e.g., prior to Rel. 17), regarding the RACH procedure for other cells (e.g., SCell), there is no such restriction as for a specific cell, and the UE is supported to receive the PDCCH for the RAR using the QCL of a specific CORESET. The specific CORESET can also be a CORESET associated with a type 1 CSS set (e.g., type 1-PDCCH CSS set).

[0188] Specifically, when the UE starts PRACH transmission in response to a PDDCCH command for triggering the CFRA procedure for the SCell and performs detection of DCI format 1_0 scrambled by CRC with the corresponding RA-RNTI, the UE can also assume the DMRS antenna port quasi-co-location characteristics of the CORESET associated with the type 1-PDCCH CSS set for receiving the PDCCH containing DCI format 1_0.

[0189] However, in order to obtain the TA for each TRP (alternatively, the TA of the serving cell and non-serving cells), the RACH for each TRP (alternatively, each serving cell / non-serving cell) can also be triggered. Regarding the PDCCH command that triggers the RACH procedure towards a TRP (alternatively, serving cell / non-serving cell), the case where the PDCCH command for the RAR and the PDCCH are sent from different TRPs is also considered. In such a case, it is necessary to relax / change the restriction that the PDCCH command for the RAR and the PDCCH have the same DMRS QCL characteristics.

[0190] For example, it is also possible to support: the PDCCH command from TRP#1 triggers the RACH towards TRP#2, and the RAR is sent from TRP#2. In this case, the RACH towards any TRP can be triggered via the PDCCH command from any TRP, which can improve the flexibility of the RACH procedure.

[0191] As another example, it is also possible to support: the PDCCH command from TRP#2 triggers the RACH towards TRP#2, and the RAR is sent from TRP#1. This example may occur in the case of inter-cell multi-TRP (e.g., inter-cell M-TRP) when the UE cannot receive the type 1 CSS set from the TRP of the non-serving cell.

[0192] (Random access procedure in the MAC entity)

[0193] The random access procedure is started by a PDCCH command, the MAC entity itself, or the RRC for an event that follows the specification. Inside the MAC entity, at any point in time, only one random access procedure is in progress. The random access procedure for the SCell is started only by a PDCCH command accompanied by a ra-PreambleIndex different from 0b000000.

[0194] When starting the random access procedure on the serving cell, the MAC entity performs the following operations.

[0195] · When the random access procedure is started by a PDCCH command and the ra-PreambleIndex explicitly provided by the PDCCH is not 0b000000, or when the random access procedure is started for accompanying the resetting of synchronization and the contention-free random access resources of the 4-step RA type are explicitly provided by rach-ConfigDedicated to the BWP selected for the random access procedure, set RA_TYPE to 4-stepRA.

[0196] When the selected RA_TYPE is set to 4-step RA, the MAC entity performs the following operations.

[0197] · When ra-PreambleIndex is explicitly provided by the PDCCH and ra-PreambleIndex is not 0b000000, set PREAMBLE_INDEX to the notified ra-PreambleIndex and select the SSB notified by the PDCCH.

[0198] · When the SSB is selected as above, starting from the PRACH opportunity corresponding to the selected SSB that is permitted according to the restriction given by ra-ssb-OccasionMaskIndex, determine the next available PRACH opportunity (the MAC entity randomly selects a PRACH opportunity with equal probability from consecutive PRACH opportunities corresponding to the selected SSB according to the specification. When the MAC entity determines the next available PRACH opportunity corresponding to the selected SSB, it can also consider the possibility of generating a measurement gap).

[0199] For example, when a new random access procedure starts during the period when other random access procedures are already in progress within the MAC entity, whether to continue the ongoing procedure or start a new procedure (such as an SI request, etc.) depends on the actual installation of the UE.

[0200] During the period when the UE receives other PDCCH commands indicating the same random access preamble, PRACH mask index, and UL carrier, if there is an ongoing random access procedure triggered by a certain PDCCH command, this procedure is regarded as the same random access procedure as the ongoing procedure and is not re-initialized.

[0201] (Contention resolution)

[0202] If Msg3 is sent, the MAC entity follows the following Operations 1 to 4.

[0203] [Operation 1] When Msg3 is sent on a non-terrestrial network, the MAC entity starts ra-ContentionResolutionTimer and restarts ra-ContentionResolutionTimer in each HARQ retransmission within the first symbol after adding the UE's estimated UE-gNB RTT to the end of Msg3.

[0204] [Operation 2] Otherwise, in the case where the Msg3 transmission (initial transmission or HARQ retransmission) is scheduled with repetitions of the type A PUSCH, the MAC entity starts or restarts the ra-ContentionResolutionTimer within the first symbol after all repetitions of the Msg3 transmission have ended.

[0205] [Operation 3] Otherwise, the MAC entity starts or restarts the ra-ContentionResolutionTimer within the first symbol after the Msg3 transmission has ended.

[0206] [Operation 4] The MAC entity monitors the PDCCH during the operation of the ra-ContentionResolutionTimer, regardless of the possibility of a measurement gap occurring.

[0207] Step 4 (Msg4) in the RA procedure of Rel. 16 NR follows the following Step 4 operation.

[0208] [Step 4 operation]

[0209] In the case where the C-RNTI is not provided to the UE, based on the PUSCH transmission scheduled by the RAR UL grant, the UE attempts to detect DCI format 1_0 with a CRC scrambled by the corresponding TCI-RNTI that schedules the PDSCH containing the UE contention resolution identity. Based on the reception of the PDSCH containing the UE contention resolution identity, the UE transmits HARQ-ACK information within the PUCCH. The PUCCH transmission is within the same active UL BWP as the PUSCH transmission. The minimum time between the last symbol of the PDSCH reception and the first symbol of the corresponding PUCCH transmission containing the HARQ-ACK information is equal to N_T,1 [msec]. N_T,1 is the duration of N_T,1 symbols corresponding to the PDSCH processing time of UE processing capability 1 in the case of setting additional PDSCH DM-RS. For μ = 0, the UE assumes N_T,1 = 14.

[0210] When detecting the DCI format for PUSCH transmission scheduled according to the RAR UL grant, or for the corresponding PUSCH retransmission scheduled according to DCI format 0_0 with a CRC scrambled by the TC-RNTI provided by the corresponding RAR message, regardless of whether the TCI state of the CORESET of the PDCCH accompanying this DCI format received by the UE is provided to the UE, the UE may also assume that the PDCCH carrying this DCI format has the same DM-RS antenna port quasi co-location (QCL) properties as those of the DM-RS antenna port for the SS / PBCH block used by the UE in the PRACH association.

[0211] In the case of configured CA, in a 4-step RA type random access procedure, the first 3 steps of CBRA may also always occur in the PCell. In this case, contention resolution (step 4) may also be cross-scheduled by the PCell. The 3 steps of CFRA started in the PCell remain on the PCell. To establish the timing advance of STAG, CFRA in the SCell may also be started only by the gNB. This procedure may also be started by the gNB via a PDCCH command (step 0) sent in the scheduling cell of the SCell activated in the STAG. The preamble transmission (step 1) may also be performed in the indicated SCell. The RAR (step 2) may also be performed in the PCell. Thus, in the existing system, in the RACH procedure in the SCell, the PDCCH command is sent in the activated SCell.

[0212] (Activation / Deactivation of SCell)

[0213] When one or more SCell are configured in the MAC entity, the network (NW) can activate / deactivate the configured SCell. After configuring the SCell, the SCell remains deactivated as long as the parameter (sCellState) is not set to active for the SCell by the higher layer.

[0214] One or more configured SCell may also be activated / deactivated based on at least one of the following conditions:

[0215] · Receiving an SCell Activation / Deactivation MAC CE.

[0216] · Receive the extended SCell Activation / Deactivation MAC CE.

[0217] · Set a timer (sCellDeactivationTimer) for each SCell (except for the SCell for which PUCCH is being configured). Additionally, if the timer expires, the associated SCell is deactivated.

[0218] · Set sCellState for each configured SCell. In this case, the associated SCell is activated based on the configuration of the SCell.

[0219] When the SCell is deactivated, the UE can also perform / envision the following operations:

[0220] · Do not transmit the SRS of the SCell.

[0221] · Do not report the CSI of the SCell.

[0222] · Do not transmit UL-SCH in the SCell.

[0223] · Do not transmit RACH in the SCell.

[0224] · Do not monitor PDCCH in the SCell.

[0225] · Do not monitor the PDCCH for the SCell.

[0226] · Do not transmit PUCCH in the SCell.

[0227] The HARQ feedback for the MAC protocol data unit (Protocol Data Unit (PDU)) containing the SCell Activation / Deactivation MAC CE or the extended SCell Activation / Deactivation MAC CE (Enhanced SCell Activation / Deactivation MAC CE) is not affected by the interruption of the PCell / PSCell / PUCCH-SCell caused by the activation / deactivation of the SCell. On the other hand, when the SCell is deactivated, if there is an ongoing random access procedure in the SCell, it is interrupted.

[0228] (Time between PDCCH command reception and PRACH transmission)

[0229] In the case where the random access procedure is started by a PDCCH command, if the UE is requested by the higher layer, the UE transmits a PRACH within the selected PRACH opportunity when the time between the last symbol of the PDCCH command reception and the first symbol of the PRACH transmission is greater than or equal to N_(T,2) + Δ_BWPSwitching + Δ_Delay + T_switch [msec] (time condition) as described in the specification. Here, N_(T,2) is the duration of the N_2 symbols corresponding to the PUSCH preparation time of the UE processing capability 1. Μ corresponds to the SCS setting for PRACH transmission. For example, it is assumed that μ corresponds to the minimum SCS setting between the subcarrier spacing (SCS) setting of the PDCCH command and the SCS setting of the corresponding PRACH transmission. When the active UL BWP does not change, Δ_BWPSwitching = 0; otherwise, Δ_BWPSwitching is defined in the specification. In FR1, Δ_delay = 0.5 msec, and in FR2, Δ_delay = 0.25 msec. T_switch is the switching gap duration defined by the specification.

[0230] When the UE is provided with K by CellSpecific_Koffset cell，offset the PRACH opportunity is after slot n + 2 μ ·K cell，offset Here, n is the slot of the UL BWP of the PRACH transmission that overlaps with the end of the reception of the PDCCH command assuming T TA = 0. Μ corresponds to the SCS setting for PRACH transmission. When the PDCCH reception for the PDCCH command includes two PDCCH candidates from two search space sets linked based on the searchSpaceLinkingId, the last symbol of the PDCCH reception is the last symbol of the PDCCH candidate that ends later. Even when the UE does not need to monitor either of the two PDCCH candidates, the PDCCH reception includes two PDCCH candidates.

[0231] When the UE responds to a PRACH transmission started by a PDCCH command that triggers the CFRA procedure for the SpCell and attempts to detect DCI format 1_0 with a CRC scrambled by the corresponding RA-RNTI, the UE can also assume that the PDCCH and the PDCCH command containing DCI format 1_0 have the same DM-RS antenna port QCL characteristics.

[0232] In the case where the UE responds to a PRACH transmission that starts with a PDCCH command triggering the CFRA process for the SCell and attempts to detect DCI format 1_0 with a CRC scrambled by the corresponding RA-RNTI, the UE may also assume the DMRS antenna port QCL characteristics of the CORESET associated with the type 1-PDCCH CSS set configured for receiving the PDCCH containing DCI format 1_0.

[0233] In this way, the timing of the PRACH opportunity is associated with μ and CellSpecific_Koffset.

[0234] (For the RACH procedure of a non-serving cell for L1 / L2 centric inter-cell mobility)

[0235] When the RRC configures more than one non-serving cell information for the UE, it may also include the RACH configuration of the non-serving cell (which can be multiple). As a case of supporting the RACH of a candidate cell triggered by a PDCCH command, the following options 1-3 can be exemplified.

[0236] <Option 1>

[0237] The UE may also determine the cell corresponding to the PDCCH command (or the PRACH transmitted according to the PDCCH command) based on specific parameters used in the PDCCH of the PDCCH command. The specific parameters may also be, for example, the TCI state.

[0238] For example, when the base station transmits a PDCCH command for PRACH and the PDCCH (or DCI / CORESET) is associated with the TCI state from a non-serving cell, the PRACH requested by the PDCCH command may also correspond to the non-serving cell. In this case, the UE may also control the PRACH transmission based on the PRACH configuration of the non-serving cell. Subsequently, the UE may also determine the TA of the non-serving cell based on the DL transmission (e.g., RAR) feedback for the PRACH transmission.

[0239] When the PDCCH (or DCI / CORESET) is associated with the TCI state from the serving cell, the PRACH requested by the PDCCH command may also correspond to the serving cell. In this case, the UE may also control the transmission of the PRACH based on the PRACH configuration of the serving cell. Subsequently, the UE may also determine the TA of the serving cell based on the DL transmission (e.g., RAR) feedback for the PRACH transmission.

[0240] <Option 2>

[0241] The UE can also determine the cell corresponding to the PDCCH command (or the PRACH transmitted according to the PDCCH command) based on the DCI (or CORESET) used in the PDCCH command.

[0242] For example, the identification information of the cell corresponding to the PRACH (e.g., cell index / cell type (e.g., serving cell / non-serving cell)) can also be included in the DCI used in the PDCCH command and notified to the UE. In a specific DCI format (e.g., DCI format 1_0) used in the PDCCH command, in order to explicitly indicate the serving cell / non-serving cell corresponding to the PRACH, X reserved bits of the DCI can also be used in the cell notification. The reserved bits can also be the reserved bits included in the DCI format 1_0 in the existing system (e.g., Rel.15 / 16).

[0243] The bit size of X can also be set / judged / decided based on the number of non-serving cells set. For example, when 1 non-serving cell is set, X can also be 1 bit. In this case, it can also be that '0' represents the serving cell and '1' represents the non-serving cell. The field used in the notification of the cell identification information can also apply the most significant bit (MSB) or the least significant bit (LSB) of the reserved bits.

[0244] In addition, when 3 non-serving cells are set, X can also be 2 bits. In order to represent the non-serving cells, the re-indexed index of the non-serving cells can also be applied. The association between the cell index and the bit value (or code point) can be defined in the specification or set by higher layer signaling, etc. For example, it can also be that the code point '0' or '00' represents the serving cell, and the remaining bits are associated with the index order (e.g., ascending / descending) of the set non-serving cells.

[0245] Or, it can also be that the size of X is fixed, regardless of the number of non-serving cells set, and the number of bits does not change. In this case, the unused bits / fields can also be configured as reserved bits.

[0246] <Option 3>

[0247] When the random access preamble index (e.g., ra-PreambleIndex) is a specific value (e.g., 0 to 63), a part of the preamble can also be set / activated by RRC / MAC CE to be associated with the non-serving cell.

[0248] In this case, the information of the serving cell / non-serving cell can also be indicated by a specific field of a specific DCI format (e.g., DCI format 1_0). The specific field can also be, for example, a random access preamble index field (e.g., RandomAccess Preamble index field). In addition, the preamble setting associated with the non-serving cell can also be set to a structure that is only applied in the PRACH transmission based on the PDCCH command (or a structure that is not applied in the contention-based PRACH transmission).

[0249] When the preamble associated with the non-serving cell is indicated by DCI, the UE can also perform control according to the RACH setting of the non-serving cell to perform a PRACH transmission with the indicated preamble.

[0250] The UE can also adjust the TA of one or more indicated cells after the PRACH based on the PDCCH command. The information related to the TA can also be received through a response signal (e.g., RAR) for the PRACH transmission.

[0251] (Problem)

[0252] However, in the RACH procedure of each TRP (or TRP TA) in the multi-TRP as described above, sufficient research has not been conducted on how to perform the RACH procedure. Specifically, the following multiple problems are envisioned.

[0253] <Problem 1>

[0254] For example, it is not clear in which cell the PDCCH command of the candidate cell is sent in the RACH procedure for the candidate cell triggered by the PDCCH command. The candidate cell is not limited to the SpCell / PCell, and the SCell can also be a candidate cell.

[0255] <Problem 1-1>

[0256] For example, it is not clear how to send the PDCCH command in the case of a non-active (deactivated) cell / deactivated candidate cell. In addition, in the existing system, the UE does not perform PDCCH monitoring in the deactivated cell.

[0257] <Problem 1-2>

[0258] In addition, when the PDCCH command is sent in each cell, the UE needs to monitor the PDCCH of multiple candidate cells (at least monitor for the PDCCH command). Furthermore, the UE may not know which candidate cell's PDCCH command to monitor.

[0259] <Problem 2-1>

[0260] The NW is able to send two PDCCH commands for two cells for the PRACH, but the indication of the preamble / mask (PRACH mask index) / UL carrier is the same (common). Therefore, the existing rules are not appropriate (cannot be applied). For example, when the UE has an ongoing random access procedure triggered by a certain PDCCH command, even if it receives another PDCCH command indicating the same random access preamble / PRACH mask index / UL carrier, it is considered that the procedure is the same random access procedure as the ongoing one and does not re-initialize.

[0261] <Problem 3>

[0262] When the RACH of a candidate cell is triggered by a PDCCH command, a preamble is sent in the candidate cell, and an RAR is sent in the PCell. When there is an ongoing random access procedure in the MAC entity (e.g., based on previous PDCCH commands for other cells), when the NW sends a PDCCH command for a certain cell, whether to continue the ongoing procedure or start a new one depends on the actual installation of the UE. Therefore, the UE cannot know which cell the received RAR is for.

[0263] <Problem 4>

[0264] As described above, in the existing system, the timing of the PRACH opportunity is associated with μ and CellSpecific_Koffset. When the cell where the PRACH is triggered is different from the cell of the PDCCH command, the interpretation method of the above parameters (μCellSpecific_Koffset) should be clarified.

[0265] <Problem 5>

[0266] As a method for obtaining the TA of a candidate cell, in addition to the method based on the RACH, a method without using the RACH (RACH-less) is also being discussed. For example, methods such as TA acquisition based on SRS, TA acquisition based on Rx timing difference, RACH-less mechanisms such as LTE, and TA measurement based on the UE (including UE-based TA measurement using one TAC from the serving cell) are given as examples. However, these methods have limitations in applicable scenarios.

[0267] <Problem 5-1>

[0268] For example, in the case of UE-based TA measurement (including TA acquisition based on Rx timing difference, etc.), since it can only be applied intra-band, there are limitations in the applicable scenarios. Specifically, in the inter-band CA scenario where DL / UL synchronization is not aligned among multiple CCs, it is envisaged as improper operation (TA of candidate cells cannot be acquired). When the UE calculates the TA of all candidate cells based on the reference CC in MCG / SCG, if the reference CC loses synchronization, all candidate cells also lose synchronization. Therefore, it is necessary to stipulate how to acquire the TA of the reference CC within each TAG, especially when all cells within the TAG are candidate cells, it is necessary to stipulate how to acquire this TA. For example, consider controlling synchronization for each TAG.

[0269] <Problem 5-2>

[0270] In addition, in the case of TA acquisition based on SRS, since it is applied to active cells (candidate cells / serving cells), there may be limitations in the applicable scenarios.

[0271] Therefore, the inventors of the present invention focused on the situation of triggering RACH, and studied the RACH process of related situations and came up with one mode of the present embodiment.

[0272] Hereinafter, with reference to the drawings, embodiments related to the present disclosure will be described in detail. The wireless communication methods related to each embodiment can be applied separately or in combination.

[0273] In the present disclosure, "A / B" and "at least one of A and B" can also be rewritten with each other. In addition, in the present disclosure, "A / B / C" can also mean "at least one of A, B, and C".

[0274] In the present disclosure, notification, activation, deactivation, indication (or specify (indicate)), selection (select), configuration (configure), update (update), determination (determine), etc. can also be rewritten with each other. In the present disclosure, support, control, be able to control, operate, be able to operate, etc. can also be rewritten with each other.

[0275] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, fields, Information Element (IE), configuration, etc. can also be rewritten with each other. In the present disclosure, Medium Access Control control element (MAC Control Element (CE)), update command, activation / deactivation command, etc. can also be rewritten with each other.

[0276] In the present disclosure, the higher layer signaling may also be any one of, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, or a combination thereof.

[0277] In the present disclosure, the MAC signaling may also use, for example, MAC Control Element (MACCE), MAC Protocol Data Unit (PDU), etc. The broadcast information may also be, for example, Master Information Block (MIB), System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0278] In the present disclosure, the physical layer signaling may also be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), etc.

[0279] In the present disclosure, an index, an identifier (ID), an indicator, a resource ID, etc. may also be rewritten with each other. In the present disclosure, a sequence, a list, a set, a group, a cluster, a subset, etc. may also be rewritten with each other.

[0280] In the present disclosure, a panel, a UE panel, a panel group, a beam, a beam group, a precoder, an Uplink (UL) transmission entity, a Transmission / Reception Point (TRP), a base station, Spatial Relation Information (SRI), a spatial relation, an SRS Resource Indicator (SRI), a Control Resource Set (CORESET), a Physical Downlink Shared Channel (PDSCH), a Codeword (CW), a Transport Block (TB), a Reference Signal (RS), an antenna port (e.g., a Demodulation Reference Signal (DMRS) port), an antenna port group (e.g., a DMRS port group), a group (e.g., a spatial relation group, a Code Division Multiplexing (CDM) group, a reference signal group, a CORESET group, a Physical Uplink Control Channel (PUCCH) group, a PUCCH resource group), a resource (e.g., a reference signal resource, an SRS resource), a resource set (e.g., a reference signal resource set), a CORESET pool, a Transmission Configuration Indication state (TCI state) for the downlink (DL TCI state), a TCI state for the uplink (UL TCI state), a unified TCI state, a common TCI state, Quasi-Co-Location (QCL), QCL assumptions, etc. may also be rewritten with each other.

[0281] In addition, a Spatial Relation Information Identifier (ID) (TCI state ID) and Spatial Relation Information (TCI state) may also be rewritten with each other. "Spatial Relation Information" may also be rewritten with "a set of Spatial Relation Information", "one or more Spatial Relation Information", etc. A TCI state and a TCI may also be rewritten with each other.

[0282] In the present disclosure, the TRP, CORESET pool index (CORESETPoolIndex), TRP ID, ID related to the TRP, TAG ID, group of TCI states, group of spatial relations, group of QCL source RSs, group of DL RSs, group of path loss RSs, PCI (for multi-TRP between cells), etc. can also be rewritten with each other.

[0283] In the present disclosure, being associated with different TRPs, being associated with different CORESET pool indexes (CORESETPoolIndex), being associated with different TRP IDs, being associated with IDs related to different TRPs, being associated with different TAG IDs, being associated with different groups of TCI states, being associated with different groups of spatial relations, being associated with different groups of QCL source RSs, being associated with different groups of DL RSs, being associated with different groups of path loss RSs, being associated with different PCIs (for multi-TRP between cells), etc. can also be rewritten with each other.

[0284] Each embodiment of the present disclosure can also be applied to at least one of intra-cell multi-TRP and inter-cell multi-TRP.

[0285] In the present disclosure, intra-cell multi-TRP may also mean that the activated TCI states of multiple (e.g., two) TRPs are associated with the same PCI.

[0286] In the present disclosure, inter-cell multi-TRP may also mean that the activated TCI states of multiple (e.g., two) TRPs are associated with different PCIs.

[0287] In the present disclosure, in the case of inter-cell multi-TRP, multiple (e.g., two) TRPs may also mean multiple (e.g., two) TRPs associated with multiple (e.g., two) PCIs.

[0288] In the present disclosure, non-serving cell, additional cell, candidate cell, target cell can also be rewritten with each other.

[0289] The following embodiments can also be applied to the case of setting / supporting the RACH procedure for each TRP (or, for each serving cell / additional cell / non-serving cell). Or, the following embodiments can also be applied to the case of setting / supporting the timing advance / timing advance group for each TRP (or, for each serving cell / additional cell / non-serving cell).

[0290] (Wireless communication method)

[0291] In the following description, cells #A and #B are candidate cells, and any one of SpCell / PCell / SCell can be used as long as not specifically mentioned.

[0292] <First Embodiment>

[0293] This embodiment relates to Problem 1. The PDCCH command sent to the UE in a certain cell #A can also trigger a PRACH in the same cell #A. For example, when the NW wants to trigger a RACH in the candidate cell #A, the NW needs to send a PDCCH command in the candidate cell #A.

[0294] [Embodiment 1-1]

[0295] This embodiment relates to Problem 1-1. The NW can also support the sending of PDCCH commands / PDCCH monitoring / PRACH sending in non-active (deactivated) cells / deactivated candidate cells. In this case, the NW does not need to indicate the ID of the candidate cell to the UE to trigger a RACH.

[0296] [Embodiment 1-2]

[0297] This embodiment relates to Problem 1-2. The UE can also determine whether it needs to monitor the PDCCH / the candidate cells to be monitored based on at least one of the following options.

[0298] [Option 1-2-1]

[0299] The NW can also set, through RRC / MAC CE, each candidate cell / TAG / each reference CC of the TAG / each candidate cell of the TAG for which the UE needs to monitor the PDCCH (including at least PDCCH commands / DCI format 1_0). The UE can also determine, based on RRC / MAC CE, each candidate cell / TAG / each reference CC of the TAG / each candidate cell of the TAG to be monitored. The candidate cells can also include deactivated SCell.

[0300] Regarding each candidate cell (including deactivated SCell) / TAG / reference CC of the TAG shown by the NW, the UE can also monitor PDCCH commands. Regarding other candidate cells, the UE can not monitor PDCCH commands. Here, the reference CC of each TAG can also mean that the NW / UE can obtain the TA based on this reference CC for all cells within the TAG.

[0301] [Option 1-2-2]

[0302] In a certain cell #A, a PDCCH command sent by a UE can also trigger a PRACH in a cell #B different from the cell #A (details will be described later in the second embodiment).

[0303] [Option 1-2-3]

[0304] The UE can also determine candidate cells for which PDCCH monitoring should be performed based on a certain (specific) rule. The specific rule can also be at least one of the following:

[0305] · Candidate cells for which L1 beam measurement / reporting is set,

[0306] · Candidate cells for which an active TCI state / TRS / CSI measurement / reporting is set,

[0307] · Candidate cells (for each TAG) with the smallest cell ID among the above candidate cells.

[0308] In this case, the UE can also determine only one candidate cell for which PDCCH monitoring should be performed for each TAG.

[0309] [Variation]

[0310] In Embodiments 1-1 and 1-2, the UE monitors, in candidate cells (deactivated cells / set cells), a DCI format with a specific DCI format (for example, DCI format 1_0 with a CRC scrambled by a corresponding RA-RNTI / C-RNTI). Thereby, the number of BDs can be reduced and the UE load can be reduced. However, it is not limited thereto. For example, the UE can also monitor an arbitrary DCI format scrambled by an arbitrary RNTI.

[0311] Figure 8A And Figure 8B is a diagram showing an example of the timing of PDCCH monitoring according to the first embodiment. The UE can also receive a PDCCH command transmitted in cell #A at the timing shown in either Figure 8A and Figure 8B The UE can receive a PDCCH command at an arbitrary timing. In this case, even if the SCell is deactivated, the UE always needs to monitor the PDCCH.

[0312] For example, as shown in Figure 8A The UE can receive a PDCCH command at an arbitrary timing. In this case, even if the SCell is deactivated, the UE always needs to monitor the PDCCH.

[0313] In addition, as shown in Figure 8BAs shown, the UE can also receive PDCCH commands at a specific timing. In this case, the UE only needs to monitor the PDCCH during a specific time duration. The monitoring period / non-monitoring period can be determined in advance in the specification or set / indicated by RRC / MAC CE / DCI. The specific time duration can also be any of the following: the same as the On duration of DRX, several parts of the DRX period, and a period that includes the DRX period.

[0314] According to the first embodiment described above, during the RACH procedure, the UE can appropriately determine in which cell the PDCCH command of the candidate cell is transmitted.

[0315] <Second Embodiment>

[0316] This embodiment relates to the following situation: The PDCCH command sent to the UE in a certain cell #A triggers a PRACH in another cell #B different from the cell #A. The cells #A and #B can belong to the same MCG / SCG or the same TAG.

[0317] [Embodiment 2-0]

[0318] In this embodiment, the UE is triggered to perform RACH based on at least one of the following options.

[0319] [Option 2-0-1]

[0320] Any active serving cell (cell #A) can also trigger a RACH for a candidate cell (cell #B (which can also be another serving cell)).

[0321] [Option 2-0-2]

[0322] It can also be that only a certain cell #A in the SPCell triggers a RACH for a candidate cell (cell #B).

[0323] [Option 2-0-3]

[0324] It can also be that only the (active) scheduling cell (cell #A) triggers a RACH for the scheduling cell (cell #B) associated with the cell #A. The association between cells #A and #B (e.g., based on cross carrier scheduling) can also be set / indicated by RRC.

[0325] A maximum number of scheduling cells can also be defined for the scheduling cell (cell #A).

[0326] If it is assumed that the scheduling cell ID is indicated by a new carrier indicator field (CIF) within a PDCCH command, for one scheduling cell (cell #B), the CIF value used within the PDCCH command can also be explicitly set via RRC. For multiple CIF values used within the PDCCH command for multiple scheduling cells, they can also be implicitly determined based on the order of the cell indexes / PCIs of the multiple scheduling cells. In the implicit case, for example, a small cell index / PCI can also be mapped to a small CIF value.

[0327] [Option 2-0-4]

[0328] Cell #A that can trigger RACH (per TAG) can be explicitly / implicitly set via RRC / MAC CE or can also be pre-defined in the specification. For example, a cell with the smallest cell ID per TAG / CG (cell group), or an active cell with the smallest cell ID per TAG / CG (cell group) can also be this cell #A (the cell that can trigger RACH).

[0329] According to Embodiment 2-0, the UE does not need to monitor PDCCH commands in deactivated cells / majority of cells. In this case, PRACH transmission in deactivated cells / deactivated candidate cells can also be supported.

[0330] To indicate the target cell of the PRACH, the target cell ID / BWP ID / frequency can also be indicated by DCI containing a PDCCH command.

[0331] The NW can indicate multiple target cells in DCI containing a PDCCH command. The UE can also select one cell based on this DCI to trigger RACH.

[0332] In the present disclosure, not limited to DCI format 1_0, DCI formats such as 1_1, 1_2, 2_X, etc., other DCI formats can also contain (apply) PDCCH commands.

[0333] [Embodiment 2-1]

[0334] This embodiment relates to Problem 2-1. When the UE has an ongoing random access process triggered by a certain PDCCH command, even if it receives other PDCCH commands indicating the same target cell ID / BWP ID / center frequency / random access preamble / PRACH mask index / UL carrier, it regards this process as the same random access process as the ongoing process and does not re-initialize.

[0335] According to the second embodiment described above, the UE can appropriately determine the triggering of RACH for the PDCCH command based on the candidate cell according to the new rule.

[0336] <Third Embodiment>

[0337] This embodiment relates to Problem 3.

[0338] [Option 3-0]

[0339] When there is an ongoing random access procedure in the MAC entity, if the NW sends a PDCCH command for a certain cell, it is determined according to the actual installation of the UE whether to continue the ongoing procedure or start a new procedure. When the UE is triggered for RCH upon receiving a PDCCH command for a certain cell from the NW, it is determined according to the actual installation from which cell the RAR is sent.

[0340] [Option 3-1]

[0341] The target cell may also be indicated in the RAR (or MAC sub-header). Thus, the UE can determine the target cell.

[0342] [Option 3-2]

[0343] The target cell may also be indicated in the DCI for scheduling the RAR (for example, DCI format 1_0 with a CRC scrambled by RA-RNTI). For example, reserved bits in the DCI may also be used to indicate the target cell.

[0344] [Option 3-3]

[0345] The following new rules may also be defined for UE operations.

[0346] <Option 3-3-1>

[0347] When the ongoing RA is for the active serving cell and the new RA is for the candidate cell, the UE may also discard the latter process (new RA).

[0348] <Option 3-3-2>

[0349] When the ongoing RA is for the candidate cell and the new RA is for the active serving cell, the UE may also preferentially start the latter process (new RA). In this case, the UE may also stop / discard the former process (ongoing RA).

[0350] In the case where the ongoing RA is the processing of a candidate cell and the new RA is also the processing of a candidate cell, the UE can also prioritize the processing of both (the ongoing RA and the new RA). Additionally, in this case, which processing to prioritize can also depend on the actual installation of the UE. Furthermore, the UE may not assume a scenario where an ongoing RA and a new RA are triggered for a candidate cell.

[0351] According to the third embodiment described above, the UE can appropriately determine the triggering of RACH based on the PDCCH command for a candidate cell according to the new rules.

[0352] <Fourth Embodiment>

[0353] This embodiment relates to Problem 4 (the method of interpreting the parameters (μ and CellSpecific_Koffset) related to the timing of the PRACH opportunity).

[0354] [Option 4-1]

[0355] Each candidate cell may also have settings related to the above parameters (μ and CellSpecific_Koffset). In this case, this setting may also be applied to the parameters of the cell for which PRACH is triggered.

[0356] [Option 4-2]

[0357] The setting related to the parameters (μ and CellSpecific_Koffset) may also be applied to the parameters of the cell for which the PDCCH command is sent.

[0358] [Option 4-3]

[0359] The setting related to the parameters (μ and CellSpecific_Koffset) may also be applied to the parameters of the SPCell.

[0360] According to the fourth embodiment described above, the UE can appropriately determine the parameters related to the timing of the PRACH opportunity.

[0361] <Fifth Embodiment>

[0362] This embodiment relates to Problem 5.

[0363] It is also possible to support an NW setting that makes a certain RACH-less solution valid for each UE / MCG / SCG / TAG / cell / serving cell / candidate cell.

[0364] [Embodiment 5-1]

[0365] This embodiment relates to Problem 5-1.

[0366] The NW can also set / indicate both the RACH triggered by the PDCCH command (PDCCH order RACH) and the TA measurement based on the UE for the TAG. The TA of the reference CC (in the case of a candidate cell) can also be configured to be obtained by the RACH triggered by the PDCCH command (PDCCH order RACH). In addition, the TA of other cells within the TAG can also be calculated and determined by UE measurement.

[0367] [Embodiment 5-2]

[0368] This embodiment relates to Problem 5-2.

[0369] The NW can also be supported to trigger SRS-based TA acquisition (SRSTx (e.g., AP-SRS / SP-SRS)) in the deactivated SCell / deactivated candidate cell. The SRS setting for the candidate cell can also be provided in the candidate cell setting. In addition, for the method of triggering SRS-based TA acquisition for the deactivated SCell / deactivated candidate cell by DCI, Embodiments 1 and 2 can be adopted.

[0370] According to the fifth embodiment described above, the UE can appropriately obtain the TA of the candidate cell in multiple scenarios.

[0371] [Notification of Information to the UE]

[0372] The notification of any information from the above-mentioned embodiment (from the Network (NW) (e.g., from the Base Station (BS))) to the UE (in other words, the reception of any information from the BS in the UE) can also be performed using physical layer signaling (e.g., DCI), high layer signaling (e.g., RRC signaling, MAC CE), specific signals / channels (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

[0373] When the above notification is performed by the MAC CE, the MAC CE can also be identified by being included in the MAC sub-header with a new logical channel ID (Logical Channel ID (LCID)) not specified in the existing specification.

[0374] In the case where the above notification is carried out by DCI, the above notification can also be carried out by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used in the scrambling of Cyclic Redundancy Check (CRC) bits assigned to the DCI, the format of the DCI, etc.

[0375] In addition, the notification of any information in the above embodiments to the UE can also be carried out periodically, semi - persistently or aperiodically.

[0376] [Notification of information from the UE]

[0377] The notification of any information from the UE (to the NW) in the above embodiments (in other words, the transmission / reporting of any information from the UE to the BS) can also be carried out using physical layer signaling (e.g., UCI), high - layer signaling (e.g., RRC signaling, MAC CE), specific signals / channels (e.g., PUCCH, PUSCH, PRACH, reference signals), or a combination thereof.

[0378] In the case where the above notification is carried out by MAC CE, the MAC CE can also be identified by being included in the MAC sub - header with a new LCID not specified in the existing specifications.

[0379] In the case where the above notification is carried out by UCI, the above notification can also be sent using PUCCH or PUSCH.

[0380] In addition, the notification of any information from the UE in the above embodiments can also be carried out periodically, semi - persistently or aperiodically.

[0381] [Applications of each embodiment]

[0382] At least one of the above embodiments can also be applied when specific conditions are met. The specific conditions can either be specified in the specifications or be notified to the UE / BS using high - layer signaling / physical layer signaling.

[0383] At least one of the above embodiments can also be applied only to UEs that have reported a specific UE capability or support the specific UE capability.

[0384] The specific UE capability can also represent at least one of the following:

[0385] · Support for specific processing / operations / controls / information regarding at least one of the above embodiments

[0386] · Support for two TAs for multiple TRPs

[0387] · Support for two TAs for multiple TRPs within a cell (e.g., intra-cell M-TRP)

[0388] · Support for two TAs for multiple TRPs between cells (e.g., inter-cell M-TRP)

[0389] · Support for L1 / L2 inter-cell mobility (e.g., L1 / L2 inter-cell mobility)

[0390] · Support for PDCCH monitoring of candidate cells / deactivated candidate cells / deactivated SCell

[0391] · Support for the maximum number of cells / TAG / reference CCs that can be the object of PDCCH monitoring

[0392] · Support for PDCCH commands across carriers (cross-CC)

[0393] In addition, the above specific UE capabilities can be capabilities that are applied across all frequencies (commonly regardless of frequency), capabilities for each frequency (e.g., one or a combination of a cell, a band, a band combination, a BWP, a component carrier, etc.), capabilities for each frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), capabilities for each subcarrier spacing (SubCarrier Spacing (SCS)), capabilities for each feature set (Feature Set (FS)) or capabilities for each feature set per component carrier (Feature Set PerComponent-carrier (FSPC)).

[0394] In addition, the above specific UE capabilities can be capabilities that are applied across all full-duplex modes (commonly regardless of the duplex mode), or capabilities for each duplex mode (e.g., Time Division Duplex (TDD), Frequency Division Duplex (FDD)).

[0395] In addition, at least one of the above-described embodiments can also be applied when the UE is set / activated / trigged by higher layer signaling / physical layer signaling with specific information associated with the above-described embodiments (or an operation for implementing the above-described embodiments). For example, the specific information can also be information indicating the activation of 8TX UL transmission, any RRC parameter for a specific version (e.g., Rel.18 / 19), etc.

[0396] Even when the UE does not support at least one of the above specific UE capabilities or the above specific information is not set, the UE can also apply operations such as Rel.15 / 16.

[0397] (Supplementary Note)

[0398] Regarding an embodiment of the present disclosure, the following inventions are noted.

[0399] [Supplementary Note 1]

[0400] A terminal, comprising:

[0401] a receiving unit that receives a downlink control channel command used in triggering a random access procedure from a candidate cell; and

[0402] a control unit that determines the candidate cell associated with the serving cell based on the downlink control channel command.

[0403] [Supplementary Note 2]

[0404] The terminal according to Supplementary Note 1, wherein

[0405] the candidate cell is a deactivated cell or a deactivated candidate cell.

[0406] [Supplementary Note 3]

[0407] The terminal according to Supplementary Note 1 or Supplementary Note 2, wherein

[0408] as a parameter of the cell that triggers the random access procedure or the cell that transmits the downlink control channel command, a parameter associated with the timing of a Physical Random Access Channel (PRACH) opportunity is set.

[0409] [Supplementary Note 4]

[0410] The terminal according to any one of Supplementary Notes 1 to 3, wherein

[0411] the receiving unit receives a setting for obtaining the timing advance of the candidate cell.

[0412] (Supplementary Note)

[0413] Regarding an embodiment of the present disclosure, the following inventions are noted.

[0414] [Appendix 1]

[0415] A terminal, comprising:

[0416] a receiving unit that receives a downlink control channel command used for triggering a random access procedure from a candidate cell to other candidate cells different from the cell; and

[0417] a control unit that determines the other candidate cells based on the downlink control channel command.

[0418] [Appendix 2]

[0419] The terminal according to Appendix 1, wherein

[0420] the other candidate cells are triggered to perform a random access procedure by the candidate cell.

[0421] [Appendix 3]

[0422] The terminal according to Appendix 1 or Appendix 2, wherein

[0423] when the receiving unit receives a downlink control channel command different from the downlink control channel command,

[0424] when there is an ongoing random access procedure triggered by the downlink control channel command, the control unit does not initialize the random access procedure based on the different downlink control channel command.

[0425] [Appendix 4]

[0426] The terminal according to any one of Appendix 1 to Appendix 3, wherein

[0427] the control unit controls other random access procedures based on a downlink control channel command different from the downlink control channel command according to the category of the cell that is the object of the ongoing random access procedure triggered by the downlink control channel command.

[0428] (Wireless communication system)

[0429] Hereinafter, the structure of a wireless communication system according to an embodiment of the present disclosure will be described. In this wireless communication system, any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof is used for communication.

[0430] Figure 9It is a diagram showing an example of the schematic structure of a wireless communication system according to an embodiment. The wireless communication system 1 (which may also be simply referred to as system 1) may also be a system that realizes communication by using Long Term Evolution (LTE) standardized by the Third Generation Partnership Project (3GPP), the 5th generation mobile communication system New Radio (5G NR), and the like.

[0431] In addition, the wireless communication system 1 may also support dual connectivity (Multi-RAT Dual Connectivity (MR-DC)) between multiple Radio Access Technologies (RATs). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), and the like.

[0432] In EN-DC, the base station (eNB) of LTE (E-UTRA) is the Master Node (MN), and the base station (gNB) of NR is the Secondary Node (SN). In NE-DC, the base station (gNB) of NR is the MN, and the base station (eNB) of LTE (E-UTRA) is the SN.

[0433] The wireless communication system 1 may also support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity where both the MN and the SN are base stations (gNBs) of NR (NR-NR Dual Connectivity (NN-DC))).

[0434] The wireless communication system 1 may also include a base station 11 that forms a macro cell C1 with a relatively wide coverage area, and a base station 12 (12a - 12c) that is disposed within the macro cell C1 and forms a small cell C2 that is narrower than the macro cell C1. The user terminal 20 may also be located within at least one cell. The configuration, number, etc. of each cell and the user terminal 20 are not limited to the manner shown in the figure. Hereinafter, without distinguishing between the base stations 11 and 12, they are collectively referred to as the base station 10.

[0435] The user terminal 20 may also be connected to at least one of the multiple base stations 10. The user terminal 20 may also utilize at least one of carrier aggregation (CA) and dual connectivity (DC) that use multiple component carriers (CCs).

[0436] Each CC may also 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 also be included in FR1, and the small cell C2 may also 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). Additionally, the frequency bands, definitions, etc. of FR1 and FR2 are not limited to these. For example, FR1 may correspond to a frequency band higher than FR2.

[0437] Furthermore, the user terminal 20 may also communicate in each CC using at least one of time division duplex (TDD) and frequency division duplex (FDD).

[0438] The multiple base stations 10 may also be connected by wire (e.g., optical fiber based on the Common Public Radio Interface (CPRI), X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is utilized as a backhaul between the base stations 11 and 12, the base station 11, which is equivalent to the upper - level station, may also be referred to as an Integrated Access Backhaul (IAB) donor, and the base station 12, which is equivalent to a relay station (relay), may also be referred to as an IAB node.

[0439] The base station 10 can also be connected to the core network 30 via other base stations 10 or directly. For example, the core network 30 can also include at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), etc.

[0440] For example, the core network 30 can also include network functions (NFs) 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), an Operation, Administration and Maintenance (Management) (OAM), etc. In addition, multiple functions can also be provided by one network node. Furthermore, communication with an external network (for example, a network) can also be performed via the DN.

[0441] The user terminal 20 can also be a terminal that supports at least one of communication methods such as LTE, LTE-A, 5G, etc.

[0442] In the wireless communication system 1, a wireless access method based on Orthogonal Frequency Division Multiplexing (OFDM) can also be used. For example, in at least one of the Downlink (DL) and the Uplink (UL), Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), etc. can also be used.

[0443] The wireless access method can also be referred to as a waveform. Additionally, in the wireless communication system 1, in the wireless access methods of the UL and the DL, other wireless access methods (e.g., other single-carrier transmission methods, other multi-carrier transmission methods) can also be used.

[0444] As a downlink channel, in the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)), a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. that are shared among the user terminals 20 can also be used.

[0445] Furthermore, as an uplink channel, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. that are shared among the user terminals 20 can also be used.

[0446] User data, high-layer control information, System Information Block (SIB), etc. are transmitted through PDSCH. User data, high-layer control information, etc. can also be transmitted through PUSCH. In addition, the Master Information Block (MIB) can also be transmitted through PBCH.

[0447] Lower-layer control information can also be transmitted through PDCCH. The lower-layer control information can also include, for example, downlink control information (Downlink Control Information (DCI)), which includes scheduling information for at least one of PDSCH and PUSCH.

[0448] In addition, the DCI that schedules PDSCH can also be referred to as DL allocation, DL DCI, etc., and the DCI that schedules PUSCH can also be referred to as UL grant, UL DCI, etc. In addition, PDSCH can also be rewritten as DL data, and PUSCH can also be rewritten as UL data.

[0449] In the detection of PDCCH, a Control Resource Set (CORESET) and a search space can also be used. A CORESET corresponds to the resource for searching for DCI. A search space corresponds to the search area and search method for PDCCH candidates. One CORESET can also be associated with one or more search spaces. The UE can also monitor the CORESET associated with a certain search space based on the search space setting.

[0450] One search space can also correspond to PDCCH candidates equivalent to one or more aggregation levels. One or more search spaces can also be referred to as a search space set. In addition, the "search space", "search space set", "search space setting", "search space set setting", "CORESET", "CORESET setting", etc. in the present disclosure can also be rewritten with each other.

[0451] Through the PUCCH, it is also possible to transmit uplink control information (Uplink Control Information (UCI)) including at least one of channel state information (Channel State Information (CSI)), delivery confirmation information (e.g., also referred to as Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (Scheduling Request (SR)). Through the PRACH, it is also possible to transmit a random access preamble for establishing a connection with a cell.

[0452] In addition, in the present disclosure, the downlink, uplink, etc. can also be expressed without the word "link". Furthermore, it can also be expressed without the word "Physical" at the beginning of various channels.

[0453] In the wireless communication system 1, it is also possible to transmit a synchronization signal (Synchronization Signal (SS)), a downlink reference signal (Downlink Reference Signal (DL-RS)), etc. As the DL-RS, in the wireless communication system 1, it is also possible to transmit a cell-specific reference signal (Cell-specific Reference Signal (CRS)), a channel state information reference signal (Channel State Information Reference Signal (CSI-RS)), a demodulation reference signal (DeModulation Reference Signal (DMRS)), a positioning reference signal (Positioning Reference Signal (PRS)), a phase tracking reference signal (Phase Tracking Reference Signal (PTRS)), etc.

[0454] The synchronization signal can, for example, also be at least one of a primary synchronization signal (Primary Synchronization Signal (PSS)) and a secondary synchronization signal (Secondary Synchronization Signal (SSS)). A signal block including SS (PSS, SSS) and PBCH (and DMRS for PBCH) can also be referred to as an SS / PBCH block, an SS block (SS Block (SSB)), etc. In addition, SS, SSB, etc. can also be referred to as reference signals.

[0455] In addition, in the wireless communication system 1, as the uplink reference signal (Uplink Reference Signal (UL-RS)), it is also possible to transmit a reference signal for measurement (sounding reference signal (Sounding Reference Signal (SRS))), a demodulation reference signal (DMRS), etc. In addition, DMRS can also be referred to as a user terminal specific reference signal (UE-specific Reference Signal).

[0456] (Base station)

[0457] Figure 10 FIG. is an example showing the structure of a base station according to an embodiment. The base station 10 includes a control unit 110, a transmission / reception unit 120, a transmission / reception antenna 130, and a transmission path interface (transmission line interface) 140. In addition, one or more of the control unit 110, the transmission / reception unit 120, the transmission / reception antenna 130, and the transmission path interface 140 may be provided respectively.

[0458] In addition, in this example, the functional blocks of the characteristic parts in the present embodiment are mainly shown, and it can be assumed that the base station 10 also has other functional blocks required for wireless communication. A part of the processing of each unit described below may also be omitted.

[0459] The control unit 110 implements the overall control of the base station 10. The control unit 110 can be composed of a controller, a control circuit, etc. described based on the common knowledge in the technical field related to the present disclosure.

[0460] The control unit 110 may also control the generation, scheduling (e.g., resource allocation, mapping), etc. of signals. The control unit 110 may also control the transmission / reception, measurement, etc. using the transmission / reception unit 120, the transmission / reception antenna 130, and the transmission path interface 140. The control unit 110 may also generate data, control information, a sequence, etc. to be transmitted as signals, and forward them to the transmission / reception unit 120. The control unit 110 may also perform call processing (setting, releasing, etc.) of communication channels, state management of the base station 10, management of radio resources, etc.

[0461] The transmission and reception unit 120 may also include a baseband unit 121, a Radio Frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may also include a transmission processing unit 1211 and a reception processing unit 1212. The transmission and reception unit 120 may be composed of a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter (phase shifter), a measurement circuit, a transmission and reception circuit, etc., which are described based on the common knowledge in the technical field related to the present disclosure.

[0462] The transmission and reception unit 120 may be configured as an integrated transmission and reception unit, or may be composed of a transmission unit and a reception unit. The transmission unit may also be composed of a transmission processing unit 1211 and an RF unit 122. The reception unit may also be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0463] The transmission and reception antenna 130 may be composed of an antenna, such as an array antenna, etc., which is described based on the common knowledge in the technical field related to the present disclosure.

[0464] The transmission and reception unit 120 may also transmit the above-mentioned downlink channels, synchronization signals, downlink reference signals, etc. The transmission and reception unit 120 may also receive the above-mentioned uplink channels, uplink reference signals, etc.

[0465] The transmission and reception unit 120 may also use digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc. to form at least one of a transmission beam and a reception beam.

[0466] The transmission and reception unit 120 (transmission processing unit 1211), for example, may also perform processing at the Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on the data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0467] The transmission / reception unit 120 (transmission processing unit 1211) can also perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filter processing (filtering), discrete Fourier transform (Discrete Fourier Transform (DFT)) processing (if necessary), inverse fast Fourier transform (Inverse Fast Fourier Transform (IFFT)) processing, precoding, digital-to-analog conversion, etc. on the bit string to be transmitted, and output a baseband signal.

[0468] The transmission / reception unit 120 (RF unit 122) can also perform modulation to the radio frequency band, filter processing, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmission / reception antenna 130.

[0469] On the other hand, the transmission / reception unit 120 (RF unit 122) can also perform amplification, filter processing (filtering), demodulation to the baseband signal, etc. on the radio frequency band signal received through the transmission / reception antenna 130.

[0470] The transmission / reception unit 120 (reception processing unit 1212) can also perform reception processing such as analog-to-digital conversion, fast Fourier transform (Fast Fourier Transform (FFT)) processing, inverse discrete Fourier transform (Inverse Discrete Fourier Transform (IDFT)) processing (if necessary), filter processing (filtering), demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing, etc. on the obtained baseband signal, and obtain user data, etc.

[0471] The transmitting and receiving unit 120 (measurement unit 123) may also perform measurements related to the received signal. For example, the measurement unit 123 may also perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may also 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 also be output to the control unit 110.

[0472] The transmission path interface 140 may also transmit and receive signals (backhaul signaling) between the device included in the core network 30 (e.g., the network node providing the NF), other base stations 10, etc., and obtain and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0473] In addition, the transmitting unit and the receiving unit of the base station 10 in the present disclosure may also be constituted by at least one of the transmitting and receiving unit 120, the transmitting and receiving antenna 130, and the transmission path interface 140.

[0474] In addition, the transmitting and receiving unit 120 may also send the downlink control channel command used in the trigger of the random access procedure from the candidate cell to the terminal. The transmitting and receiving unit 120 may also send the downlink control channel command used in the trigger of the random access procedure for another candidate cell different from the cell from a certain candidate cell to the terminal.

[0475] The candidate cell associated with the serving cell may also be determined based on the downlink control channel command. The control unit 110 may also determine the other candidate cell based on the downlink control channel command.

[0476] (User Terminal)

[0477] Figure 11FIG. 0 is an example showing the structure of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transmission / reception unit 220, and a transmission / reception antenna 230. In addition, one or more of the control unit 210, the transmission / reception unit 220, and the transmission / reception antenna 230 may be provided respectively.

[0478] In addition, in this example, functional blocks of the characteristic parts in the present embodiment are mainly shown, and it can be assumed that the user terminal 20 also has other functional blocks required for wireless communication. A part of the processing of each unit described below may also be omitted.

[0479] The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, a control circuit, etc. described based on common knowledge in the technical field related to the present disclosure.

[0480] The control unit 210 may also control signal generation, mapping, etc. The control unit 210 may also control transmission / reception, measurement, etc. using the transmission / reception unit 220 and the transmission / reception antenna 230. The control unit 210 may also generate data, control information, sequences, etc. to be transmitted as signals and forward them to the transmission / reception unit 220.

[0481] The transmission / reception unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transmission / reception unit 220 can be composed of a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transmission / reception circuit, etc. described based on common knowledge in the technical field related to the present disclosure.

[0482] The transmission / reception unit 220 may be configured as an integrated transmission / reception unit or may be composed of a transmission unit and a reception unit. The transmission unit may be composed of the transmission processing unit 2211 and the RF unit 222. The reception unit may be composed of the reception processing unit 2212, the RF unit 222, and the measurement unit 223.

[0483] The transmission / reception antenna 230 can be composed of an antenna described based on common knowledge in the technical field related to the present disclosure, such as an array antenna.

[0484] The transmission / reception unit 220 may also receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transmission / reception unit 220 may also transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0485] The transmission / reception unit 220 may also form at least one of a transmission beam and a reception beam by using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

[0486] The transmission / reception unit 220 (transmission processing unit 2211) may also perform, for example, 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.

[0487] The transmission / reception unit 220 (transmission processing unit 2211) may also perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filter processing (filtering), DFT processing (if necessary), IFFT processing, precoding, digital-to-analog conversion, etc. on the bit string to be transmitted, and output a baseband signal.

[0488] In addition, regarding whether to apply DFT processing, it may also be based on the setting of transform precoding. For a certain channel (e.g., PUSCH), when the transform precoding is effective (enabled), the transmission / reception unit 220 (transmission processing unit 2211) may also perform DFT processing as the above-mentioned transmission processing in order to transmit the channel using the DFT-s-OFDM waveform, otherwise, the transmission / reception unit 220 (transmission processing unit 2211) may not perform DFT processing as the above-mentioned transmission processing.

[0489] The transmission / reception unit 220 (RF unit 222) may also perform modulation to a radio frequency band, filter processing (filtering), amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmission / reception antenna 230.

[0490] On the other hand, the transmission / reception unit 220 (RF unit 222) may also perform amplification, filter processing (filtering), demodulation to a baseband signal, etc. on the radio frequency band signal received through the transmission / reception antenna 230.

[0491] The transmission / reception unit 220 (reception processing unit 2212) may also perform reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filter processing (filtering), demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing, etc. on the obtained baseband signal, and obtain user data, etc.

[0492] The transmitting and receiving unit 220 (measurement unit 223) may also perform measurements related to the received signal. For example, the measurement unit 223 may also perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may also 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 also be output to the control unit 210.

[0493] In addition, the transmitting unit and the receiving unit of the user terminal 20 in the present disclosure may also be constituted by at least one of the transmitting and receiving unit 220 and the transmitting and receiving antenna 230.

[0494] In addition, the transmitting and receiving unit 220 may also receive a downlink control channel command used for triggering in the random access procedure from a candidate cell. The candidate cell may also be a deactivated cell or a deactivated candidate cell. As a parameter of the cell that triggers the random access procedure or the cell that transmits the downlink control channel command, a parameter associated with the timing of the physical random access channel (PRACH) opportunity may also be set. The transmitting and receiving unit 220 may also receive a downlink control channel command used for triggering a random access procedure performed on another candidate cell different from the cell. The other candidate cell may also be triggered to perform a random access procedure through the candidate cell. The transmitting and receiving unit 220 may also receive a downlink control channel command different from the downlink control channel command. The transmitting and receiving unit 220 may also receive a setting for obtaining the timing advance of the candidate cell.

[0495] The control unit 210 may also determine the candidate cell associated with the serving cell based on the downlink control channel command. The control unit 210 may also determine the other candidate cell based on the downlink control channel command. In the case where the transmitting and receiving unit 220 receives a downlink control channel command different from the downlink control channel command and there is an ongoing random access procedure triggered by the downlink control channel command, the control unit 210 may not initialize the random access procedure based on the different downlink control channel command. The control unit 210 may also control other random access procedures based on a downlink control channel command different from the downlink control channel command according to the category of the cell that is the object of the ongoing random access procedure triggered by the downlink control channel command.

[0496] (Hardware Structure)

[0497] In addition, the block diagrams used in the description of the above embodiments illustrate blocks of functional units. These functional blocks (structural units) are implemented by any combination of at least one of hardware and software. Furthermore, there is no particular limitation on the implementation method of each functional block. That is, each functional block can be implemented by a single device physically or logically combined, or two or more physically or logically separated devices can be directly or indirectly (e.g., by wire, wireless, etc.) connected and implemented by these multiple devices. A functional block can also be implemented by combining the above single device or the above multiple devices with software.

[0498] Here, among the functions, there are judgment, decision, determination, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, regarded as, broadcasting, notification, communication, forwarding, configuration (setting), reconfiguration (reconfiguring), allocation (allocating, mapping), assignment, etc., but are not limited to these. For example, a functional block (structural unit) that implements the transmission function may also be referred to as a transmitting unit, a transmitter, etc. Any one of them is as described above, and its implementation method is not particularly limited.

[0499] For example, a base station, a user terminal, etc. in an embodiment of the present disclosure can also function as a computer that performs the processing of the wireless communication method of the present disclosure. Figure 12 FIG. is an example of the hardware structure of a base station and a user terminal according to an embodiment. The above base station 10 and user terminal 20 can also 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.

[0500] In addition, in the present disclosure, terms such as device, circuit, equipment, section, unit, etc. can be rewritten with each other. The hardware structure of the base station 10 and the user terminal 20 can be configured to include one or more of each device shown in the figure, or can be configured not to include some devices.

[0501] For example, only one processor 1001 is illustrated, but there may be multiple processors. In addition, the processing may be executed by one processor, or may be executed by two or more processors simultaneously, sequentially, or by other means. Further, the processor 1001 may also be implemented by one or more chips.

[0502] Regarding the respective functions in the base station 10 and the user terminal 20, for example, by reading a specific software (program) into hardware such as the processor 1001 and the memory 1002, the processor 1001 performs operations and controls communication via the communication device 1004, or controls at least one of reading and writing of data in the memory 1002 and the storage 1003, thereby implementing the functions.

[0503] The processor 1001, for example, operates an operating system to control the entire computer. The processor 1001 may also be constituted by a central processing unit (Central Processing Unit (CPU)) including an interface with peripheral devices, a control device, an arithmetic device, registers, etc. For example, at least a part of the above control unit 110 (210), transmission / reception unit 120 (220), etc. may also be implemented by the processor 1001.

[0504] In addition, the processor 1001 reads a program (program code), software module, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and performs various processes based on them. As the program, a program that causes a computer to execute at least a part of the operations described in the above embodiments can be used. For example, the control unit 110 (210) may also be implemented by a control program stored in the memory 1002 and operating in the processor 1001, and the same applies to other functional blocks.

[0505] The memory 1002 may also be a computer-readable recording medium, for example, constituted by at least one of a read-only memory (Read Only Memory (ROM)), an erasable programmable read-only memory (Erasable Programmable ROM (EPROM)), an electrically erasable programmable read-only memory (Electrically EPROM (EEPROM)), a random access memory (Random Access Memory (RAM)), and other appropriate storage media. The memory 1002 may also be referred to as a register, a cache, a main memory (main storage device), etc. The memory 1002 can store a program (program code), software module, etc. executable for implementing the wireless communication method according to an embodiment of the present disclosure.

[0506] The storage device 1003 can also be a computer-readable recording medium, which is composed of at least one of, for example, a flexible disc, a floppy (registered trademark) disc, an optical disc (such as a compact disc (compact disc read-only memory (CD-ROM)), a digital versatile disc, a Blu-ray (registered trademark) disc), a removable disc, a hard disk drive, a smart card, a flash memory device (such as a card, a stick, a key drive), a magnetic stripe, a database, a server, and other appropriate storage media. The storage device 1003 can also be referred to as an auxiliary storage device.

[0507] The communication device 1004 is hardware (a transmitting and receiving device) for performing inter-computer communication via at least one of a wired network and a wireless network, and is also referred to as a network device, a network controller, a network card, a communication module, etc. In order to implement at least one of, for example, Frequency Division Duplex (FDD) and Time Division Duplex (TDD), the communication device 1004 can also be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. For example, the above-mentioned transmitting and receiving unit 120 (220), transmitting and receiving antenna 130 (230), etc. can also be implemented by the communication device 1004. The transmitting and receiving unit 120 (220) can also be physically or logically separated into a transmitting unit 120a (220a) and a receiving unit 120b (220b).

[0508] The input device 1005 is an input device for accepting external input (such as a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.). The output device 1006 is an output device for performing external output (such as a display, a speaker, a Light Emitting Diode (LED) lamp, etc.). In addition, the input device 1005 and the output device 1006 can also be of an integrated structure (such as a touch panel).

[0509] In addition, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 can be composed of a single bus or different buses can be used between each device.

[0510] In addition, the base station 10 and the user terminal 20 may also be configured to include hardware such as a microprocessor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), and a Field Programmable Gate Array (FPGA). Part or all of the functional blocks may also be implemented using this hardware. For example, the processor 1001 may also be implemented using at least one of these hardware components.

[0511] (Variant example)

[0512] Furthermore, regarding the terms described in this disclosure and the terms necessary for understanding this disclosure, they may also be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may also be rewritten with each other. In addition, a signal may also be a message. A reference signal can also be abbreviated as RS and may also be referred to as a pilot, a pilot signal, etc. according to the applied standard. In addition, a Component Carrier (CC) may also be referred to as a cell, a frequency carrier, a carrier frequency, etc.

[0513] A radio frame may also be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) that make up the radio frame may also be referred to as a subframe. Further, a subframe may also be composed of one or more time slots in the time domain. A subframe may also be a fixed time length (e.g., 1 ms) independent of the numerology.

[0514] Here, the numerology may also be communication parameters applied in at least one of the transmission and reception of a certain signal or channel. For example, the numerology may also represent at least one of a SubCarrier Spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a Transmission Time Interval (TTI), the number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transmitter-receiver in the frequency domain, a specific windowing process performed by a transmitter-receiver in the time domain, etc.

[0515] A time slot can also be composed of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.). In addition, a time slot can also be a time unit based on a parameter set.

[0516] A time slot can also contain multiple mini-slots. Each mini-slot can also be composed of one or more symbols in the time domain. In addition, a mini-slot can also be referred to as a sub-slot. A mini-slot can also be composed of a smaller number of symbols than a time slot. The PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot can also be referred to as PDSCH (PUSCH) mapping type A. The PDSCH (or PUSCH) transmitted using a mini-slot can also be referred to as PDSCH (PUSCH) mapping type B.

[0517] A radio frame, a sub-frame, a time slot, a mini-slot, and a symbol all represent time units when transmitting signals. A radio frame, a sub-frame, a time slot, a mini-slot, and a symbol can also use their respective other names. In addition, the time units such as frames, sub-frames, time slots, mini-slots, and symbols in this disclosure can also be rewritten with each other.

[0518] For example, a sub-frame can also be referred to as a TTI, multiple consecutive sub-frames can also be referred to as a TTI, and a time slot or a mini-slot can also be referred to as a TTI. That is, at least one of a sub-frame and a TTI can be a sub-frame (1 ms) in the existing LTE, or a period shorter than 1 ms (for example, 1 - 13 symbols), or a period longer than 1 ms. In addition, the unit representing a TTI can also not be referred to as a sub-frame, but as a time slot, a mini-slot, etc.

[0519] Here, a TTI refers to, for example, the minimum 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 in each user terminal) to each user terminal in units of TTI. In addition, the definition of a TTI is not limited to this.

[0520] A TTI can also be the transmission time unit of a data packet (transmission block), a code block, a codeword, etc. that has undergone channel coding, and can also become a processing unit for scheduling, link adaptation, etc. In addition, when a TTI is given, the time interval (such as the number of symbols) actually mapped with a transmission block, a code block, a codeword, etc. can also be shorter than this TTI.

[0521] In addition, when a time slot or a mini-slot is referred to as a TTI, more than one TTI (i.e., more than one time slot or more than one mini-slot) can also be the minimum time unit for scheduling. In addition, the number of time slots (mini-slots) that constitute the minimum time unit of this scheduling can also be controlled.

[0522] A TTI with a time length of 1 ms can also be referred to as a normal TTI (TTI in 3GPP Rel.8-12), a standard TTI, a long TTI, a normal subframe, a standard subframe, a long subframe, a time slot, etc. A TTI shorter than the normal TTI can also be referred to as a shortened TTI, a short TTI, a partial TTI, a shortened subframe, a short subframe, a mini-slot, a sub-slot, a time slot, etc.

[0523] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) can also be rewritten as a TTI with a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) can also be rewritten as a TTI with a TTI length less than that of the long TTI and 1 ms or more.

[0524] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and can also include one or more consecutive subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in an RB can be the same regardless of the parameter set, for example, it can be 12. The number of subcarriers included in an RB can also be determined based on the parameter set.

[0525] In addition, an RB can also include one or more symbols in the time domain, and can also be the length of a time slot, a mini-slot, a subframe, or a TTI. One TTI, one subframe, etc. can also be composed of one or more resource blocks respectively.

[0526] In addition, one or more RBs can also 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.

[0527] In addition, a resource block can also be composed of one or more resource elements (REs). For example, one RE can also be a radio resource area of a subcarrier and a symbol.

[0528] A Bandwidth Part (BWP) (which may also be referred to as partial bandwidth, etc.) can also represent a subset of consecutive common RBs (common resource blocks) used for a certain parameter set in a certain carrier. Here, the common RBs can also be determined by the indices of the RBs based on the common reference point of the carrier. PRBs can also be defined in a certain BWP and be numbered additionally within that BWP.

[0529] A BWP can also include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). For a UE, one or more BWPs can also be set within a carrier.

[0530] It can also be that at least one of the set BWPs is activated, and the UE may not assume to transmit and receive specific signals / channels outside the activated BWP. Additionally, "cell", "carrier", etc. in the present disclosure can also be rewritten as "BWP".

[0531] In addition, the structures such as the above-mentioned radio frames, subframes, time slots, mini-slots, and symbols are merely illustrative. For example, the number of subframes included in a radio frame, the number of time slots in each subframe or radio frame, the number of mini-slots included in a time slot, the symbols and the number of RBs included in a time slot or mini-slot, the number of subcarriers included in an RB, and the number of symbols, symbol length, Cyclic Prefix (CP) length, etc. within a TTI can be changed in various ways.

[0532] Furthermore, the information, parameters, etc. described in the present disclosure can be represented by absolute values, relative values with respect to a specific value, or can also be represented by corresponding other information. For example, radio resources can also be indicated by a specific index.

[0533] In the present disclosure, the names used for parameters, etc. are not restrictive names in all aspects. Furthermore, the mathematical formulas, etc. using these parameters can also be different from those clearly disclosed in the present disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable names, and thus, the various names assigned to these various channels and information elements are not restrictive names in all aspects.

[0534] The information, signals, etc. described in the present disclosure can also be represented using any one of various different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be mentioned throughout the above description can also be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0535] In addition, information, signals, etc. can be output in at least one of the following directions: from a higher layer (upper layer) to a lower layer (lower layer), and from a lower layer to a higher layer. Information, signals, etc. can also be input and output via multiple network nodes.

[0536] The input and output information, signals, etc. can be stored in a specific location (e.g., a memory), or can be managed using a management table. The input and output information, signals, etc. can be overwritten, updated, or appended. The output information, signals, etc. can also be deleted. The input information, signals, etc. can also be sent to other devices.

[0537] The notification of information is not limited to the methods / embodiments described in this disclosure, and other methods can also be used. For example, the notification of information in this disclosure can also be implemented through physical layer signaling (e.g., downlink control information (Downlink Control Information (DCI)), uplink control information (Uplink Control Information (UCI))), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB), etc.), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0538] In addition, physical layer signaling can also be referred to as layer 1 / layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. In addition, RRC signaling can also be referred to as an RRC message, and can also be, for example, an RRC connection setup message, an RRC connection reconfiguration (RRC connection re - setting (RRCConnection Reconfiguration)) message, etc. In addition, MAC signaling can, for example, also be notified using a MAC control element (MACControl Element (CE)).

[0539] In addition, the notification of specific information (e.g., the notification of "is X") is not limited to explicit notification, and can also be performed implicitly (e.g., by not performing the notification of the specific information, or by the notification of other information).

[0540] The determination can be made by a value represented by one bit (0 or 1), by a true / false value (Boolean value) represented by true or false, or by a comparison of numerical values (e.g., comparison with a specific value).

[0541] Software, whether referred to as software, firmware, middleware, micro-code, hardware description language, or by any other name, should be broadly construed to mean instructions, instruction sets, code, code segments, program code, programs, sub-programs, software modules, applications, software applications, software packages, routines, sub-routines, objects, executable files, execution threads, processes, functions, etc.

[0542] In addition, software, instructions, information, etc. can also be transmitted and received via a transmission medium. For example, when software is transmitted from a website, server, or other remote source using at least one of wired technologies (coaxial cables, fiber optic cables, twisted pairs, Digital Subscriber Line (DSL), etc.) and wireless technologies (infrared, microwave, etc.), at least one of these wired and wireless technologies is included in the definition of the transmission medium.

[0543] Terms such as "system" and "network" used in this disclosure can be used interchangeably. "Network" can also mean a device (e.g., a base station) included in the network.

[0544] 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", "transmission power", "phase rotation", "antenna port", "antenna port group", "layer", "number of layers", "rank", "resource", "resource set", "resource group", "beam", "beam width", "beam angle", "antenna", "antenna element", "panel", etc. can be used interchangeably.

[0545] 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. can be used interchangeably. There are also cases where base stations are referred to by terms such as macro cell, small cell, femto cell, pico cell, etc.

[0546] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also provide communication services through a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). Terms such as "cell" or "sector" refer to a part or the whole of the coverage area of at least one of the base station and the base station subsystem that provides communication services within that coverage range.

[0547] In the present disclosure, the situation where a base station sends information to a terminal can also be rewritten as the base station instructing the terminal to perform control / operations based on that information.

[0548] In the present disclosure, terms such as "Mobile Station (MS)", "user terminal", "user device (User Equipment (UE))", and "terminal" can be used interchangeably.

[0549] There are also cases where the mobile station is referred to by subscriber station, mobile unit, subscriber unit, radio unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, hand set, user agent, mobile client, client, or several other suitable terms.

[0550] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a wireless communication device, etc. In addition, at least one of the base station and the mobile station may also be a device mounted in a moving object, the moving object itself, etc.

[0551] The moving object refers to an object that can move, and the moving speed can be arbitrary. Of course, it also includes the case where the moving object stops. The moving object includes, for example, vehicles, transport vehicles, automobiles, motorcycles, bicycles, Connected Cars, loading shovels, bulldozers, wheel loaders, dump trucks, fork lifts, trains, buses, trolleys, rickshaws, ships (ships and other watercraft), airplanes, rockets, artificial satellites, drones, multicopters, quadcopters, hot air balloons, and objects mounted on them. In addition, it is not limited to these. Furthermore, the moving object may also be a moving object that autonomously travels based on an operation instruction.

[0552] The moving object can be a means of transportation (e.g., vehicles, airplanes, etc.), a moving object that moves in an unmanned manner (e.g., drones, autonomous vehicles, etc.), or a robot (humanoid or non - humanoid). In addition, at least one of the base station and the mobile station also includes a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may also be an Internet of Things (IoT) device such as a sensor.

[0553] Figure 13 This is a diagram showing an example of a vehicle related 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, an axle 48, an electronic control unit 49, various sensors (including a current sensor 50, a rotational speed sensor 51, a 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.

[0554] The drive unit 41 is composed of, for example, at least one of an engine, a motor, and a hybrid of an engine and a motor. The steering unit 42 is configured to include at least a steering wheel (also referred to as a handle), and steers at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by the user.

[0555] The electronic control unit 49 is composed of a microprocessor 61, a memory (ROM, RAM) 62, and a communication port (for example, an Input / Output (IO) port) 63. Signals from various sensors 50 - 58 provided in the vehicle are input into the electronic control unit 49. The electronic control unit 49 may also be referred to as an Electronic Control Unit (ECU).

[0556] As signals from various sensors 50 - 58, there are a current signal from the current sensor 50 that senses the current of the motor, a rotational speed signal of the front wheels 46 / rear wheels 47 obtained by the rotational speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 obtained by the pressure sensor 52, a vehicle speed signal obtained by the vehicle speed sensor 53, an acceleration signal obtained by the acceleration sensor 54, a depression amount signal of the accelerator pedal 43 obtained by the accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 obtained by the brake pedal sensor 56, an operation signal of the shift lever 45 obtained by the shift lever sensor 57, a detection signal obtained by the object detection sensor 58 for detecting obstacles, vehicles, pedestrians, etc.

[0557] The information service unit 59 is composed of various devices such as a navigation system, an audio system, a speaker, 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 the information obtained from an external device via the communication module 60, etc., to provide various information / services (for example, multimedia information / multimedia services) to the occupants of the vehicle 40.

[0558] The information service unit 59 may include an input device (e.g., keyboard, mouse, microphone, switch, button, sensor, touch panel, etc.) that accepts inputs from the outside, or may include an output device (e.g., display, speaker, LED light, touch panel, etc.) that performs outputs to the outside.

[0559] The driving assistance system unit 64 is composed of various devices such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, locators (e.g., Global Navigation Satellite System (GNSS), etc.), map information (e.g., High Definition (HD) map, Autonomous Vehicle (AV) map, etc.), gyroscopic systems (e.g., Inertial Measurement Unit (IMU), Inertial Navigation System (INS), etc.), Artificial Intelligence (AI) chips, AI processors, etc., which provide functions for preventing accidents in advance or reducing the driver's driving burden, and one or more ECUs that control these devices. In addition, the driving assistance system unit 64 transmits and receives various information via the communication module 60 to implement driving assistance functions or autonomous driving functions.

[0560] The communication module 60 can communicate with the microprocessor 61 and the structural elements 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 between the driving unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axle 48, microprocessor 61 and memory (ROM, RAM) 62, and various sensors 50 - 58 provided in the vehicle 40.

[0561] The communication module 60 can be controlled by the microprocessor 61 of the electronic control unit 49 and is a communication device capable of communicating with external devices. For example, various information is transmitted and received with external devices via wireless communication. The communication module 60 can be inside or outside the electronic control unit 49. The external device can also be, for example, the above-mentioned base station 10, user terminal 20, etc. In addition, the communication module 60 can also be at least one of the above-mentioned base station 10 and user terminal 20 (and can also function as at least one of the base station 10 and user terminal 20).

[0562] The communication module 60 can also transmit at least one of the following to an external device via wireless communication: signals from the various sensors 50 - 58 input to the electronic control unit 49, information obtained based on such signals, and information based on inputs from the outside (users) obtained via the information service unit 59. The electronic control unit 49, various sensors 50 - 58, information service unit 59, etc. can also be referred to as input units that accept inputs. For example, the PUSCH transmitted via the communication module 60 can also contain information based on the above inputs.

[0563] The communication module 60 receives various information (traffic information, traffic light information, vehicle - to - vehicle information, etc.) sent from an external device and displays it on the information service unit 59 provided in the vehicle. The information service unit 59 can also be referred to as an output unit that outputs information (for example, information output to devices such as a display and a speaker based on the PDSCH received via the communication module 60 (or data / information decoded according to the PDSCH)).

[0564] In addition, the communication module 60 stores various information received from an external device in a memory 62 that can be utilized by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 can also control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axle 48, various sensors 50 - 58, etc. provided in the vehicle 40.

[0565] In addition, the base station in the present disclosure can also be rewritten as a user terminal. For example, for a structure in which communication between a base station and a user terminal is replaced by communication between multiple user terminals (for example, it can also be referred to as Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.), the various methods / embodiments of the present disclosure can also be applied. In this case, it can also be configured such that the user terminal 20 has the functions of the above-mentioned base station 10. In addition, terms such as "uplink" and "downlink" can also be rewritten as terms corresponding to inter-terminal communication (for example, "sidelink"). For example, an uplink channel, a downlink channel, etc. can also be rewritten as a sidelink channel.

[0566] Similarly, the user terminal in the present disclosure can also be rewritten as a base station. In this case, it can also be configured such that the base station 10 has the functions of the above-mentioned user terminal 20.

[0567] In the present disclosure, the actions performed by the base station sometimes may also be performed by its upper node according to circumstances. Apparently, in a network including one or more network nodes having a base station, various operations for communicating with a terminal can be performed by the base station, one or more network nodes other than the base station (for example, considering a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc., but not limited to these), or a combination thereof.

[0568] The various methods / embodiments described in the present disclosure can be used alone, in combination, or switched during execution. In addition, the processing procedures, timings, flowcharts, etc. of the various methods / embodiments described in the present disclosure can also be reordered as long as there is no contradiction. For example, regarding the methods described in the present disclosure, the elements of various steps are presented in an exemplary order, but are not limited to the specific order presented.

[0569] Each mode / embodiment described in the present disclosure can also be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, the 4th generation mobile communication system (4G), the 5th generation mobile communication system (5G), the 6th generation mobile communication system (6G), the xth generation mobile communication system (xG (x is an integer or a decimal, for example)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), systems using other appropriate wireless communication methods, next-generation systems extended, modified, generated, or defined based on them, etc. In addition, multiple systems can also be combined (for example, a combination of LTE or LTE-A and 5G) for application.

[0570] The description "based on" used in the present disclosure, unless otherwise specified, does not mean "only based on". In other words, the description "based on" means both "only based on" and "at least based on".

[0571] Any reference to an element using the terms "first", "second", etc. used in this disclosure does not fully define the amount or order of these elements. These terms can be used in this disclosure as a convenient method to distinguish between two or more elements. Therefore, reference to the first and second elements does not mean that only two elements can be used or that the first element must take precedence over the second element in some form.

[0572] The term "determining" used in this disclosure may include a variety of actions. For example, "determining" may also refer to situations where judging, calculating, computing, processing, deriving, investigating, looking up (e.g., searching in a table, database or other data structure), ascertaining, etc. are considered to be "determining".

[0573] In addition, “judgment (decision)” may also refer to situations where receiving (e.g., receiving information), transmitting (e.g., sending information), input (input), output (output), accessing (e.g., accessing data in a memory), etc. are regarded as making a “judgment (decision)”.

[0574] In addition, "judgment (decision)" can also be regarded as a situation where resolving, selecting, choosing, establishing, comparing, etc. are regarded as "judgment (decision)". That is, "judgment (decision)" can also be regarded as a situation where some actions are regarded as "judgment (decision)".

[0575] In addition, "judge (decide)" can also be rewritten as "assuming (assuming)", "expecting (expecting)", "considering (considering)" and so on.

[0576] The “maximum transmit power” described in the present disclosure may refer to the maximum value of the transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0577] As used in this disclosure, the terms "connected" and "coupled", or any of their variations, mean all direct or indirect connections or couplings between two or more elements, and can include the situation where there is one or more intermediate elements between the two elements that are "connected" or "coupled" to each other. The coupling or connection between elements can be physical, logical, or a combination of them. For example, "connected" can also be rewritten as "access".

[0578] In this disclosure, when two elements are connected, it is possible to consider that they are "connected" or "coupled" to each other by using one or more wires, cables, printed electrical connections, etc., and as several non-limiting and non-inclusive examples, electromagnetic energy with wavelengths in the radio frequency domain, microwave region, and optical (both visible and invisible) region, etc., is used to be "connected" or "coupled" to each other.

[0579] In this disclosure, the term "A is different from B" can also mean "A and B are different from each other". Additionally, this term can also mean "A and B are each different from C". Terms such as "separated" and "combined" can also be interpreted in the same way as "different".

[0580] When the terms "include", "including", and their variations are used in this disclosure, these terms, like the term "comprising", have an inclusive meaning. Furthermore, the term "or" used in this disclosure does not mean the exclusive or.

[0581] In this disclosure, for example, when articles are added through translation such as a, an, and the in English, this disclosure can also include the case where the nouns following these articles are in the plural form.

[0582] In this disclosure, terms such as "below", "less than", "above", "more than", "equal" can also be rewritten with each other. In addition, in this disclosure, terms that mean "good", "bad", "big", "small", "high", "low", "early", "late", "wide", "narrow", etc., are not limited to the positive, comparative, and superlative degrees, and can also be rewritten with each other. In addition, in this disclosure, for terms that mean "good", "bad", "big", "small", "high", "low", "early", "late", "wide", "narrow", etc., with the expression "the i-th" (i is any integer) attached, they are not limited to the positive, comparative, and superlative degrees, and can also be rewritten with each other (for example, "highest" and "the i-th highest" can also be rewritten with each other).

[0583] In the present disclosure, "of", "for", "regarding", "related to", "associated with", etc. may also be rewritten with each other.

[0584] As described above, the invention related to the present disclosure has been described in detail. However, for those skilled in the art, the invention related to the present disclosure is obviously not limited to the embodiments described in the present disclosure. The invention related to the present disclosure can be implemented in the form of corrections and changes without departing from the gist and scope of the invention determined based on the description of the claims. Therefore, the description of the present disclosure is for illustrative purposes and does not convey any restrictive meaning to the invention related to the present disclosure.

Claims

1. A terminal, comprising: a receiving unit configured to receive a downlink control channel command used for triggering a random access procedure from a candidate cell; and a control unit configured to determine the candidate cell associated with a serving cell based on the downlink control channel command.

2. The terminal according to claim 1, wherein the candidate cell is a deactivated cell or a deactivated candidate cell.

3. The terminal according to claim 1, wherein a parameter set to be associated with the timing of a physical random access channel (PRACH) opportunity is used as a parameter of the cell that triggers the random access procedure or the cell that transmits the downlink control channel command.

4. The terminal according to claim 1, wherein the receiving unit receives a setting for obtaining a timing advance of the candidate cell.

5. A wireless communication method, which is a wireless communication method of a terminal, comprising: receiving, from a candidate cell, a downlink control channel command used for triggering a random access procedure; and determining, based on the downlink control channel command, the candidate cell associated with a serving cell.

6. A base station, comprising: a transmitting unit configured to transmit a downlink control channel command used for triggering a random access procedure from a candidate cell to a terminal; and a control unit configured to determine the candidate cell associated with a serving cell based on the downlink control channel command.

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