Terminal, wireless communication method, base station and system

Abstract

A terminal according to one embodiment of the present disclosure includes: a reception unit that receives a setting related to the repetition of a physical random access channel; and a control unit that controls transmission of the repetition, in association with the same beam. According to one embodiment of the present disclosure, coverage of a random access procedure can be improved.

Description

[Technical Field]

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

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

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

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

[0005] In future wireless communication systems (e.g., NR), improvements in coverage are being considered.

[0006] However, the random access procedure for improving coverage is not clear, and if such a random access procedure is not clear, communication throughput may decrease.

[0007] Therefore, the present disclosure provides a terminal and a wireless communication method that improve the coverage of a random access procedure. 、 base station and systems One of the aims is to provide [Means for solving the problem]

[0008] A terminal according to one aspect of the present disclosure includes: A transmitter that repeatedly transmits a random access preamble and, When transmitting the second or subsequent random access preambles in the repeated transmission, the transmission counter, the power ramping counter, and the reception target power of the random access preamble are not incremented. and a control unit for controlling the [Effects of the Invention]

[0009] According to one aspect of the present disclosure, the coverage of the random access procedure can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows an example of a RACH configuration information element. [Figure 2] 2A and 2B show an example of PRACH occasion and beam association. [Figure 3] FIG. 3 shows an example of a PRACH configuration. [Figure 4] FIG. 4 shows an example of a short sequence PRACH format. [Figure 5] 5A and 5B show an example of unit resource 1 / 2. [Figure 6] 6A and 6B show an example of a unit resource 3. FIG. [Figure 7] 7A and 7B show an example of unit resource 4 / 5. [Figure 8] 8A and 8B show another example of the unit resource 5. FIG. [Figure 9] FIG. 9 shows yet another example of the unit resource 5. [Figure 10] 10A and 10B show an example of a unit resource 2 according to variation A. [Figure 11] 11A and 11B show an example of a unit resource 5 according to variation A. FIG. [Figure 12] 12A and 12B show an example of variation A1. [Figure 13] FIG. 13 shows an example of the transmission operation 1. [Figure 14] FIG. 14 shows an example of the transmission operation 2. [Figure 15] FIG. 15 shows an example of the transmission operation 3. [Figure 16] FIG. 16 shows an example of monitoring operation 2. [Figure 17] FIG. 17 shows an example of window operation 1 / 2. [Figure 18] FIG. 18 shows an example of window operations 3a / 3b / 3c. [Figure 19] 19A and 19B show an example of the ninth embodiment. [Figure 20] FIG. 20 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. [Figure 21] FIG. 21 is a diagram illustrating an example of the configuration of a base station according to an embodiment. [Figure 22] FIG. 22 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. [Figure 23] FIG. 23 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. [Figure 24] FIG. 24 is a diagram illustrating an example of a vehicle according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (TCI, spatial relations, QCL) In NR, it is being considered to control the reception processing (e.g., at least one of reception, demapping, demodulation, and decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, and encoding) in the UE of at least one of a signal and a channel (referred to as signal / channel) based on the transmission configuration indication state (TCI state).

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

[0013] The TCI state is information about the quasi-co-location (QCL) of signals / channels, and may also be called spatial reception parameters, spatial relation information, etc. The TCI state may be configured in the UE for each channel or signal.

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

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

[0016] A plurality of types (QCL types) of QCLs may be defined. For example, four QCL types A and B may be provided, each having different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may also be referred to as QCL parameters) are listed below: QCL Type A (QCL-A): Doppler shift, Doppler spread, mean delay and delay spread, QCL Type B (QCL-B): Doppler shift and Doppler spread, QCL Type C (QCL-C): Doppler shift and mean delay, · QCL Type D (QCL-D): Spatial reception parameters.

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

[0018] The UE may determine at least one of a transmit beam (Tx beam) and a receive beam (Rx beam) for a signal / channel based on the TCI condition or QCL assumption of the signal / channel.

[0019] The TCI state may be, for example, information about the QCL between the target channel (in other words, the Reference Signal (RS) for the channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by higher layer signaling, physical layer signaling, or a combination thereof.

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

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

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

[0023] An SSB is a signal block that includes at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). An SSB may also be referred to as an SS / PBCH block.

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

[0025] (Initial Access Procedures) In the initial access procedure, the UE (RRC_IDLE mode) receives the SS / PBCH block (SSB), transmits Msg.1 (PRACH / random access preamble / preamble), receives Msg.2 (PDCCH, PDSCH including random access response (RAR)), transmits Msg.3 (PUSCH scheduled by RAR UL grant), and receives Msg.4 (PDCCH, PDSCH including UE contention resolution identity). After that, when the base station (network) transmits an ACK for Msg.4 from the UE, an RRC connection is established (RRC_CONNECTED mode).

[0026] SSB reception includes PSS detection, SSS detection, PBCH-DMRS detection, and PBCH reception. PSS detection detects part of the physical cell ID (PCI), detects (synchronizes) OFDM symbol timing, and performs (coarse) frequency synchronization. SSS detection includes detecting the physical cell ID. PBCH-DMRS detection includes detecting (part of) the SSB index within a half radio frame (5 ms). PBCH reception includes detecting the system frame number (SFN) and radio frame timing (SSB index), receiving configuration information for receiving remaining minimum system information (RMSI, SIB1), and recognizing whether the UE can camp on that cell (carrier).

[0027] SSB has a bandwidth of 20 RB and a time of 4 symbols. The transmission period of SSB can be set to {5, 10, 20, 40, 80, 160} ms. In the half frame, multiple symbol positions of SSB are specified based on the frequency range (FR1, FR2).

[0028] The PBCH has a payload of 56 bits. N repetitions of the PBCH are transmitted within a period of 80 ms, where N depends on the SSB transmission period.

[0029] The system information consists of the MIB, RMSI (SIB1), and other system information (OSI) carried by the PBCH. SIB1 contains information for RACH configuration and RACH procedures. The time / frequency resource relationship between the SSB and the PDCCH monitoring resource for SIB1 is configured by the PBCH.

[0030] A base station using beam correspondence transmits multiple SSBs using multiple beams in each SSB transmission period. The multiple SSBs have multiple SSB indices. When a UE detects an SSB, it transmits a PRACH in the RACH occasion associated with that SSB index and receives an RAR in the RAR window.

[0031] (Beam and Coverage) In high-frequency bands, if beamforming is not applied to synchronization signals / reference signals, coverage will be narrow, making it difficult for UEs to find base stations. On the other hand, if beamforming is applied to synchronization signals / reference signals to ensure coverage, a strong signal will reach a specific direction, but the signal will be even less likely to reach other directions. If the base station does not know the direction of the UE before it connects, it is impossible to transmit synchronization signals / reference signals using beams pointing only in the appropriate direction. One possible method is for the base station to transmit multiple synchronization signals / reference signals, each with a beam pointing in a different direction, and for the UE to recognize which beam it has found. Using thin (narrow) beams for coverage requires transmitting many synchronization signals / reference signals, which increases overhead and may reduce frequency utilization efficiency.

[0032] In order to reduce the number of beams (synchronization signals / reference signals) and reduce overhead, using a thick (wide) beam results in a narrower coverage area.

[0033] In future wireless communication systems (e.g., 6G), it is expected that the use of frequency bands such as millimeter waves and terahertz waves will become more widespread. It is conceivable that communication services will be provided by constructing cell areas / coverage using multiple narrow beams.

[0034] It is possible to expand the coverage area by using the existing FR2, or to use a higher frequency band than the existing FR2. To achieve these, it is desirable to improve beam management in addition to multi-TRP, reconfigurable intelligent surface (RIS), etc.

[0035] Coverage extensions are being considered, including PRACH extensions for frequency range (FR) 2. For example, PRACH repetition using the same or different beams is being considered.

[0036] As shown in the example of Figure 1, the common RACH configuration (RACH-ConfigCommon) may include a general RACH configuration (rach-ConfigGeneric), a total number of RA preambles (totalNumberOfRA-Preambles), and an SSB per RACH occasion and a contention-based (CB) preamble per SSB (ssb-perRACH-OccasionAndCB-PreamblesPerSSB). rach-ConfigGeneric may include a PRACH configuration index (prach-ConfigurationIndex) and a message 1 FDM (msg1-FDM, the number of PRACH occasions FDMed in one time instance). ssb-perRACH-OccasionAndCB-PreamblesPerSSB may include the number of CB preambles per SSB for one Eighth SSBs per RACH occasion (one Eighth, one SSB associated with eight RACH occasions).

[0037] For a Type 1 random access procedure (four-step random access procedure, messages 1 / 2 / 3 / 4), the UE may apply the number N of SS / PBCH blocks associated with one PRACH occasion and the number R of CB preambles per SS / PBCH block per enabled PRACH occasion via ssb-perRACH-OccasionAndCB-PreamblesPerSSB.

[0038] For a Type 1 random access procedure, or for a Type 2 random access procedure with PRACH occasion configuration independent of the Type 1 random access procedure (two-step random access procedure, messages A / B), if N<1, one SS / PBCH block is mapped to 1 / N consecutive valid RACH occasions, and for each valid PRACH occasion, R CB preambles with consecutive indices associated with the SS / PBCH block index are provided, starting with preamble index 0. If N>=1, R CB preambles with consecutive indices associated with the SS / PBCH block index n (0<=n<-N-1) are provided, starting with preamble index n·N_preamble^total / N, where N_preamble^total is given by totalNumberOfRA-Preambles for a Type 1 random access procedure, and by msgA-TotalNumberOfRA-Preambles for a Type 2 random access procedure with PRACH occasion configuration independent of the Type 1 random access procedure. N_preamble^total is a multiple of N.

[0039] Starting from frame 0, the association period for mapping SS / PBCH blocks to PRACH occasions is the smallest value in the set determined by the PRACH configuration period according to the relationship (defined in the specification) between the PRACH configuration period and the association period (number of PRACH configuration periods) such that N_Tx^SSB SS / PBCH block indices are mapped to a PRACH occasion at least once within the association period. Here, the UE derives N_Tx^SSB from the value of SSB positions in burst (ssb-PositionsInBurst) in SIB1 or in the common serving cell configuration (ServingCellConfigCommon). If, after an integer number of mapping cycles from SS / PBCH block indices to PRACH occasions within the association period, there is a set of PRACH occasions or PRACH preambles that are not mapped to N_Tx^SSB SS / PBCH block indices, then no SS / PBCH block index is mapped to that set of PRACH occasions or PRACH preambles. The association pattern period includes one or more association periods and is determined such that the pattern between PRACH occasions and SS / PBCH block indices repeats at most every 160 ms. If, after an integer number of association periods, there is a PRACH occasion that is not associated with an SS / PBCH block index, that PRACH occasion is not used for PRACH.

[0040] For PRACH configuration periods of 10, 20, 40, 80, and 160 msec, the association periods are {1,2,4,8,16}, {1,2,4,8}, {1,2,4}, {1,2}, and {1}, respectively.

[0041] FIG. 2A shows an example (mapping 1) of association of PRACH occasions (RACH occasions (ROs)) and beams (SSB / CSI-RS). When ssb-perRACH-OccasionAndCB-PreamblesPerSSB indicates oneHalf,n16 (N=½, R=16) and msg1-FDM is 4, four ROs are FDM-multiplexed in one time instance, and one SSB is mapped to two ROs. Preamble indexes 0 to 15 are associated with two ROs, and preamble indexes 0 to 15 are associated with SS0B. In this way, when N<1, one SSB is mapped to multiple ROs. This increases the capacity of ROs per beam.

[0042] FIG. 2B shows another example (mapping 2) of RO-to-beam association. When ssb-perRACH-OccasionAndCB-PreamblesPerSSB indicates n4,n16 (N=4, R=16), msg1-FDM is 4, and N_preamble^total is 64, four ROs are FDM-multiplexed in one time instance, and four SSBs are mapped to one RO. Each RO is associated with SSBs 0 to 3. Preamble indices 0 to 15 are associated with SSB 0, preamble indices 15 to 31 are associated with SSB 1, preamble indices 32 to 47 are associated with SSB 2, and preamble indices 48 to 63 are associated with SSB 3. In this way, the same RO is associated with different SS / PBCH block indices, and different preambles use different SS / PBCH block indices. The base station can distinguish the associated SS / PBCH block indices based on the received PRACH.

[0043] The random access preamble can only be transmitted in the time resources specified in the random access configuration of the specification, and depends on whether FR1 or FR2 and the spectrum type (paired spectrum / supplementary uplink (SUL) / unpaired spectrum). The PRACH configuration index is given by the higher layer parameter prach-ConfigurationIndex or, if configured, by msgA-PRACH-ConfigurationIndex. In the specification, each value of the PRACH configuration index is associated with at least one of the following: preamble format, x and y in n_f (frame number) mod x = y, subframe number, starting symbol, number of PRACH slots in a subframe, number of time-domain PRACH occasions in a PRACH slot N_t^RA,slot, and PRACH duration N_dur^RA (Figure 3).

[0044] Whether PRACH repetition is applicable to a scenario, the type of RACH procedure triggered by different purposes is different. The type of RACH procedure may be at least one of the following: Contention-free random access (CFRA), PDCCH ordered RA (RA initiated by a PDCCH order), CFRA for beam failure recovery (BFR), CFRA for system information (SI) request, CFRA for reconfiguration with sync, etc. Contention-based random access (CBRA), RA triggered by the MAC entity, RA triggered by RRC with events, CBRA for BFR, etc. 4-step RACH. · 2-step RACH.

[0045] However, the settings / procedures for PRACH repetition are unclear. For example, it is unclear how PRACH resources for repetition (e.g., repetition pattern, repetition number) are set, the UE operation of preamble repetition transmission, the impact on counters / timers related to RACH, etc. If such settings / procedures are unclear, there is a risk of degradation in communication quality / communication throughput.

[0046] (RA response window) RA Response Window (ra-ResponseWindow) is the time window for monitoring RA Responses (RAR) (SpCell only). RA Contention Resolution Timer (ra-ContentionResolutionTimer) is the timer for RA contention resolution (SpCell only). Msg.B Response Window is the time window for monitoring RA Responses (RAR) for 2-step RA types (SpCell only).

[0047] Once the RA preamble is transmitted, the MAC entity performs the following actions 1 to 3, regardless of whether a measurement gap may occur.

[0048] [Operation 1] If a contention-free RA preamble for a BFR request is transmitted by the MAC entity, the MAC entity performs the following operations 1-1 and 1-2. [[Operation 1-1]] The MAC entity starts the ra-ResponseWindow configured in the BFR configuration (BeamFailureRecoveryConfig) on ​​the first PDCCH occasion from the end of the RA preamble transmission. [[Operation 1-2]] While the ra-ResponseWindow is running, the MAC entity monitors PDCCH transmissions in the search space indicated by the BFR search space ID (recoverySearchSpaceId) of the SpCell identified by the C-radio network temporary identifier (RNTI).

[0049] [Operation 2] If not, the MAC entity performs the following operations 2-1 and 2-2. [[Operation 2-1]] The MAC entity starts the ra-ResponseWindow configured in the common RACH configuration (RACH-ConfigCommon) on the first PDCCH occasion from the end of the RA preamble transmission. [[Operation 2-2]] The MAC entity monitors the PDCCH transmission of the SpCell for the RAR identified by the RA-RNTI while the ra-ResponseWindow is running.

[0050] [Operation 3] If the ra-ResponseWindow configured in BeamFailureRecoveryConfig expires and a PDCCH transmission on the search space indicated by recoverySearchSpaceId addressed to the C-RNTI is received on the serving cell on which the preamble was transmitted, or if the ra-ResponseWindow configured in RACH-ConfigCommon expires and an RAR is received containing RA preamble identifiers matching the transmitted preamble index (PREAMBLE_INDEX), the MAC entity shall consider the RAR reception as a failure and increment the preamble transmission counter (PREAMBLE_TRANSMISSION_COUNTER) by 1.

[0051] The MAC entity may stop the ra-ResponseWindow (stop monitoring for RARs) after successful reception of an RAR containing RA preamble identifiers matching the transmitted PREAMBLE_INDEX.

[0052] For PDCCH monitoring within the RA response window, there are two cases: PDCCH for the base station's response to BFR and PDCCH for RAR. The following content may apply to both cases.

[0053] When the MSGA (Msg. A) preamble is transmitted, the MAC entity performs the following actions 4 to 6, regardless of whether a measurement gap may occur.

[0054] [Operation 4] The MAC entity starts the Msg.B response window (msgB-ResponseWindow) in the PDCCH monitoring window defined in the specification.

[0055] The msgB-ResponseWindow may start at the first symbol of the earliest CORESET for which the UE is configured to receive a PDCCH for a Type 1-PDCCH CSS set, which is at least one symbol after the last symbol of the PRACH occasion corresponding to the PRACH transmission. The length of the msgB-ResponseWindow may correspond to the SCS for the Type 1-PDCCH CSS set.

[0056] [Operation 5] The MAC entity monitors the PDCCH transmission of the SpCell for RAR identified by MSGB-RNTI while the msgB-ResponseWindow is running.

[0057] [Operation 6] If a C-RNTI MAC CE is included in its MSGA, the MAC entity monitors the PDCCH transmission of the SpCell for RAR identified by the C-RNTI while the msgB-ResponseWindow is running.

[0058] The RA-RNTI associated with the PRACH occasion on which the RA preamble is transmitted is calculated as follows: RA-RNTI = 1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

[0059] where s_id is the index of the first OFDM symbol of the PRACH occasion (0<=s_id<14). t_id is the index of the first slot of the PRACH occasion in the system frame (0<=t_id<80). The subcarrier spacing (SCS) for determining t_id is based on the value of μ. f_id is the index of the PRACH occasion in the frequency domain (0<=f_id<8). ul_carrier_id is the UL carrier used for RA preamble transmission (0 for normal uplink (NUL) carrier, 1 for supplementary uplink (SUL) carrier). RA-RNTI is calculated according to the specification. RA-RNTI is the RNTI for 4-step RACH.

[0060] The MSGB-RNTI associated with the PRACH occasion on which the RA preamble is transmitted is calculated as follows: MSGB-RNTI = 1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2

[0061] where s_id is the index of the first OFDM symbol of the PRACH occasion (0<=s_id<14). t_id is the index of the first slot of the PRACH occasion in the system frame (0<=t_id<80). The subcarrier spacing (SCS) for determining t_id is based on the value of μ. f_id is the index of the PRACH occasion in the frequency domain (0<=f_id<8). ul_carrier_id is the UL carrier used for RA preamble transmission (0 for normal uplink (NUL) carrier, 1 for supplementary uplink (SUL) carrier). MSGB-RNTI is the RNTI for the 2-step RACH.

[0062] However, the repetition of RAR is unclear. For example, it is unclear whether Msg.2 supports repetition, the impact on ra-ResponseWindow, the impact on RA-RNTI, etc. If such settings / procedures are unclear, there is a risk of degradation in communication quality / communication throughput.

[0063] Therefore, the present inventors came up with the idea of ​​repeating settings / procedures in the random access procedure.

[0064] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0065] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0066] In the present disclosure, terms such as activate, deactivate, indicate (or indicate), select, configure, update, and determine may be read interchangeably. In the present disclosure, terms such as support, control, controllable, operate, and operate may be read interchangeably.

[0067] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, information elements (IEs), configurations, etc. may be interchangeable. In the present disclosure, Medium Access Control (MAC) control elements (CEs), update commands, activation / deactivation commands, etc. may be interchangeable.

[0068] In the present disclosure, higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, and the like, or a combination thereof.

[0069] In the present disclosure, MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. Broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0070] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), and the like.

[0071] In this disclosure, the terms index, identifier (ID), indicator, resource ID, etc. may be interchangeable. In this disclosure, the terms sequence, list, set, group, cluster, subset, etc. may be interchangeable.

[0072] In this disclosure, the terms panel, UE panel, panel group, beam, beam group, precoder, Uplink (UL) transmitting entity, Transmission / Reception Point (TRP), base station, Spatial Relation Information (SRI), spatial relation, SRS Resource Indicator (SRI), Control Resource Set (CORESET), Physical Downlink Shared Channel (PDSCH), Codeword (CW), Transport Block (TB), Reference Signal (RS), antenna port (e.g., Demodulation Reference Signal (DMRS) port), antenna port group (e.g., DMRS port group), group (e.g., spatial relation group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) group, PUCCH resource group), resource (e.g., reference signal resource, SRS resource), resource set (e.g., reference signal resource set), CORESET pool, downlink Transmission Configuration Indication state (TCI state) (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, Quasi-Co-Location (QCL), QCL assumption, etc. may be read as interchangeable.

[0073] In the present disclosure, the SSB / CSI-RS index / indicator, beam index, and TCI state may be read interchangeably.

[0074] (Wireless communication method) In each embodiment, the terms period, cycle, frame, subframe, slot, symbol, occasion, and RO may be interchangeable.

[0075] In each embodiment, the terms "repetition period," "repetition periodicity," and "repetition cycle" may be interchangeable.

[0076] In each embodiment, occasion, RACH occasion (RO), PRACH occasion, and recurring resource may be interchangeable.

[0077] In each embodiment, the PRACH, preamble, PRACH preamble, sequence, preamble format, and message (Msg.) 1 may be interchangeable. In each embodiment, the response to the PRACH, RAR, Msg. 2, Msg. B, and Msg. 4 may be interchangeable. In each embodiment, transmissions other than the PRACH in the random access procedure, Msg. 3, PUSCH scheduled by RAR, HARQ-ACK / PUCCH for Msg. 4, and Msg. A PUSCH may be interchangeable.

[0078] In each embodiment, the terms beam, SSB, and SSB index may be interchangeable.

[0079] In each embodiment, repetition, repetition with the same beam, repetition RO with the same beam, and repetition associated with different SSB indices may be read interchangeably.

[0080] In each embodiment, the terms random access (RA) procedure, CFRA / CBRA, 4-step RACH / 2-step RACH, a specific type of random access procedure, and a random access procedure using a specific PRACH format may be interchangeable.

[0081] For coverage extension, PRACH repetition may be applied.

[0082] If the PRACH is repeated multiple times, the coverage (link budget) of the PRACH increases. For the PRACH repetition, only PRACH format B4 (the format with the longest short sequence (the most symbols)) may be applied, or some other PRACH formats may be applied, or all PRACH formats may be applied.

[0083] 4 shows an example of PRACH formats (formats A1, A2, A3, B1, B2, B3, B4, C0, C2) for short sequences. For short sequences, the PRACH formats may be scaled based on the PRACH SCS.

[0084] Only a 4-step RACH may be applied to the PRACH repetition, which is most likely to be used in scenarios with limited coverage. A 2-step RACH may also be applied to the PRACH repetition.

[0085] First Embodiment This embodiment relates to PRACH repetition.

[0086] For CFRA / CBRA, PRACH repetition with the same beam may be applied to at least one RA of the following objects 1a-1 to 1a-6. [Subject 1a-1] CFRA only. [Subject 1a-2] CBRA only. [Subject 1a-3] Both the CFRA and the CBRA. [Subject 1a-4] Among the CFRA and CBRA, the RA reported by the UE capability. For at least one of the CFRA and CBRA, the UE capability regarding PRACH repetition with the same beam may be defined, and the UE capability may report that the UE supports PRACH repetition with the same beam for at least one of the CFRA and CBRA RA. [Subject 1a-5] CFRA and CBRA, which are configured by RRC signaling. For an RRC CONNECTED UE, RRC signaling may configure PRACH repetition enable / disable for at least one of CFRA and CBRA. [Subject 1a-6] RA for a specific RA purpose. Regarding PRACH repetition, at least one of availability and UE capability may be defined for a specific RA purpose, and the specific RA purpose may be indicated by at least one of the availability and the UE capability. The availability may be an information element (higher layer parameter) that enables PRACH repetition for an RA for the specific RA purpose. The UE capability may indicate that PRACH repetition is supported for an RA for the specific RA purpose. The specific RA purpose may be, for example, a PDCCH order RA, an RA for SI request, an RA for BFR, an RA triggered by the MAC layer, an RA triggered by the RRC layer, etc.

[0087] For 2-step RA / 4-step RA, PRACH repetition with the same beam may be applied to at least one RA of the following subjects 1b-1 to 1b-5. [Subject 1b-1] 2-step RA only. [Subject 1b-2] 4-step RA only. [Subject 1b-3] Both 2-step RA and 4-step RA. [Subject 1b-4] Among the two-step RA and the four-step RA, the UE capability is reported. For at least one of the two-step RA and the four-step RA, the UE capability for PRACH repetition with the same beam is defined, and the UE capability may report that the UE supports PRACH repetition with the same beam for at least one of the two-step RA and the four-step RA. [Subject 1b-5] 2-step RA and 4-step RA configured by RRC signaling. For an RRC_CONNECTED UE, RRC signaling may configure PRACH repetition enable / disable for at least one of 2-step RA and 4-step RA.

[0088] Considering different PRACH formats, PRACH repetition may be applied to some or all PRACH formats, and UE capability regarding PRACH repetition may be defined for one, some, or all PRACH formats.

[0089] The PRACH repetition with the same beam may be applied to some or all of the RRC IDLE UEs, RRC INACTIVE UEs, and RRC CONNECTED UEs. A new PRACH configuration for applying the PRACH repetition with the same beam to IDLE / INACTIVE UEs may be provided in the SIB. A new PRACH configuration / indication for applying the PRACH repetition with the same beam to CONNECTED UEs may be provided by RRC signaling / MAC CE / DCI.

[0090] At least one of the conditions / objectives for which PRACH repetitions with the same beam can be used in this embodiment may be the conditions / objectives for which PRACH repetitions with different beams can be used.

[0091] According to this embodiment, the conditions / objectives for which PRACH repetitions with the same beam or different are applied become clear.

[0092] <Second embodiment> This embodiment relates to the configuration of the repetition pattern / resource / number of repetitions of the PRACH.

[0093] The PRACH repetition pattern / resource may be repeated for at least one unit resource among the following unit resources 1 to 6. The at least one unit resource among the unit resources 1 to 6 may be configured by the SIC / RRC IE or may be specified in a specification. [Unit Resource 1] Association Period. The association period may be X SSB mapping periods / cycles, or may be a period that includes ROs mapped to all SSBs and unused ROs that can be mapped to beams for repetition. [Unit resource 2] PRACH setting period / cycle. [Unit Resource 3] X time units. For example, the time unit may be a slot / subframe / time domain PRACH occasion (RO). [Unit resource 4] X frequency units. For example, the frequency units may be PRACH occasions in the frequency domain. [Unit Resource 5] X PRACH Occasions (RO). [Unit Resource 6] X SSBs (PRACH Occasions (ROs) mapped to X SSBs).

[0094] From unit resource 1 to unit resource 6, two PRACH repetitions corresponding to the same SSB are closer to each other.

[0095] For unit resource 1, the second and subsequent repeating resources may occur after all SSBs have been mapped to PRACH occasions at least once. In the example of FIG. 5A, the length of the PRACH configuration period is 10 ms. In this example, the repeating resource (association period) is two PRACH configuration periods. In each repeating resource, there are ROs for SSBs 0 to 40 in the first PRACH configuration period, and ROs for SSBs 41 to 63 and unused ROs in the second PRACH configuration period. PRACH is repeated in the ROs for the same SSBs in each repeating resource. In this example, unused ROs are not used for repetition.

[0096] For unit resources 2 to 6, a second repeating resource may occur before all SSBs have been mapped to a PRACH occasion at least once. In the example of Figure 5B for unit resource 2, the repeating resource is one PRACH configuration period. In this example, the number of repetitions is 2. Within each of the first and second repeating resources (PRACH configuration periods), there are ROs for SSBs 0 to 40. Within the next first and second repeating resources (PRACH configuration periods), there are ROs for SSBs 41 to 63 and an unused RO. PRACH is repeated in the ROs for the same SSB within each repeating resource.

[0097] In the example of Figure 6A for unit resource 3, the repetition resource is 2 ms. In this example, the number of repetitions is 2. In each of the first and second repetition resources, there is an RO for SSBs 0 to 9. In each of the next first and second repetition resources, there is an RO for SSBs 10 to 19. The PRACH is repeated in the RO for the same SSB in each repetition resource.

[0098] In the example of Figure 6B for unit resource 3, the repeating resource is two time-domain ROs according to the above-mentioned mapping 1. In the first repeating resource, SSBs 0, 0, 1, and 1 are mapped to four ROs in the first time-domain RO, and SSBs 2, 2, 3, and 3 are mapped to four ROs in the second time-domain RO. The same SSBs as in the first repeating resource are also mapped in the second repeating resource. PRACH is repeated in the ROs for the same SSBs in each repeating resource.

[0099] In the example of Figure 7A for unit resource 4, the repeating resource is two frequency domain ROs according to the above mapping 2. SSBs 0 to 3 and SSBs 4 to 7 are mapped to two frequency domain ROs in the first time domain RO in the first repeating resource, respectively. The same SSBs as in the first repeating resource are also mapped to the second repeating resource. The PRACH is repeated in the ROs for the same SSBs in each repeating resource.

[0100] In the example of Figure 7B for unit resource 5, the repeating resource is four ROs according to the above-mentioned mapping 2. SSBs 0 to 3, SSBs 4 to 7, SSBs 8 to 11, and SSBs 12 to 15 are mapped to the four ROs in the first repeating resource (first time-domain RO), respectively. The same SSBs as in the first repeating resource are also mapped to the second repeating resource (second time-domain RO). PRACH is repeated in the ROs for the same SSBs in each repeating resource.

[0101] In the example of Figure 8A for unit resource 5, according to the above-mentioned mapping 2, the repeated resource is one RO. SSBs 0 to 3 are mapped to one RO in the first repeated resource (first frequency domain RO). The same SSBs as in the first repeated resource are also mapped to the second repeated resource (second frequency domain RO). PRACH is repeated in the RO for the same SSB in each repeated resource.

[0102] In the example of Figure 8B for unit resource 5, according to the above mapping 1, the repeating resource is one SSB (RO mapped to one SSB). One SSB is mapped to two frequency domain ROs. SSB0 is mapped to the first and second ROs (first and second frequency domain ROs) in the first repeating resource. The same SSB as in the first repeating resource is also mapped to the second repeating resource (third and fourth ROs, third and fourth frequency domain ROs). PRACH is repeated in the ROs for the same SSB in each repeating resource.

[0103] The number of repetitions may be explicitly or implicitly set / indicated by the SIB / RRC IE, or may be specified in the specifications.

[0104] In the explicit indication, the repetition number Y may be set to 1, 2, 3, 4, etc. Y=1 may indicate no repetition. Along with the repetition number, the repetition period / cycle may be configured for the UE or calculated / determined by the UE. For example, in the above-mentioned unit resource 1, if the repetition number is 2, the UE may determine / calculate the repetition period as 20*2=40 ms. That is, Y repetitions may occur within 40 ms.

[0105] The explicit instruction may only indicate whether repetition is invalid (none) or repetition is valid. In this case, a default number of repetitions may be specified in the specification. When the explicit instruction indicates that repetition is valid, the number of repetitions may be the default number of repetitions.

[0106] The cell-specific PRACH repetition number may be broadcast by the SIB. The UE-specific PRACH repetition number may be set by the RRC. The UE-specific PRACH repetition number may be applied to the PRACH of the RRC INACTIVE / CONNECTED UE. The UE may determine the actual PRACH repetition number according to the determination rule or UE implementation. For example, if the measured values of the SSB's RSRP / RSRQ / SINR / quality / power are lower than the threshold and the UE is set with PRACH repetition, the UE may transmit the PRACH multiple times (transmit the PRACH repetition). The threshold may be specified in the specification or set by the RRC IE. A plurality of thresholds / ranges associated with the PRACH repetition number may be set. For example, the UE may determine the PRACH repetition number corresponding to the maximum threshold below which its measured value falls among the plurality of thresholds, or may determine the PRACH repetition number corresponding to the range including its measured value among the plurality of ranges. For example, when the measured value is RSRP and the measured value < M_1 [dBm], the number of repetitions may be 4, when M_1 < measured value <= M_2 [dBm], the number of repetitions may be 2, and when M_2 < measured value [dBm], the number of repetitions may be 1.

[0107] The operation of the UE to determine the number of repetitions may be applicable only to UEs that support PRACH repetition.

[0108] In the implicit instruction, the UE may determine / calculate the repetition number based on a decision rule or a restriction. For example, the UE may calculate the repetition number based on the instruction / specified repetition period. For example, in the above-mentioned unit resource 1, if the repetition period is specified / set to 160 ms, the UE may determine / calculate the repetition period as 160 ms / 20=8 ms.

[0109] The repetition period may mean that all indicated SSB index to RO mappings are repeated Y times within that period.

[0110] In the example of Figure 9 for unit resource 5, according to the above-mentioned mapping 2, the number of repetitions is 3, and the repetition resource is one RO. SSBs 0 to 3 are mapped to one RO in the first repetition resource (first frequency domain RO). The same SSB as in the first repetition resource is also mapped to each of the second and third repetition resources (second and third frequency domain ROs). PRACH is repeated in the RO for the same SSB in each repetition resource.

[0111] The first PRACH transmission may always be a single PRACH transmission. If there is no Msg.2 (RAR) reception, the UE may transmit a PRACH with repetition. The PRACH with repetition may be accompanied by power ramping.

[0112] Variation A Different PRACH resources (including preambles / ROs) may be configured with different repetition numbers. In this case, for cases where coverage is limited, the UE can select an RO / preamble with repetition settings. A UE with good coverage can select an RO / preamble without repetition settings. For example, the UE may have a repetition number of 1 for SSBs 0 to 15, a repetition number of 2 for SSBs 16 to 31, a repetition number of 3 for SSBs 32 to 47, and a repetition number of 4 for SSBs 48 to 63. For example, the repetition number for preambles 0 to 31 may be 1, and the repetition number for preambles 32 to 63 may be 4.

[0113] In the example of Figure 10A for unit resource 2, the repetition resource is one PRACH configuration period (10 ms). The number of repetitions of ROs for SSBs 0 to 40 is 2, and the number of repetitions of ROs for SSBs 41 to 63 is 1. Within each of the first and second repetition resources (PRACH configuration periods), there are ROs for SSBs 0 to 40. PRACH is repeated in the ROs for the same SSBs within each repetition resource. Within the next PRACH configuration period, there are ROs for SSBs 41 to 63 and an unused RO. PRACH within this PRACH configuration period is not repeated.

[0114] 10B for unit resource 2, the repetition resource is one PRACH configuration period (10 ms). In this example, the repetition number for preambles 0 to 15 is 2, and the repetition number for preambles 16 to 31 is 1.

[0115] If any of preambles 0 to 15 is used, the number of repetitions is 2. Within each of the first and second repetition resources (PRACH configuration periods), there is an RO for SSBs 0 to 40. Within each of the next first and second repetition resources (PRACH configuration periods), there is an RO for SSBs 41 to 63 and an unused RO. PRACH is repeated in the RO for the same SSB within each repetition resource. If the base station decodes / receives preamble 1 associated with SSB #x within the first repetition resource, it is assumed that the base station will decode / receive the same preamble associated with the same SSB within the second repetition resource. The base station may perform joint decoding / reception to improve PRACH decoding / reception performance.

[0116] If any of preambles 16 to 31 is used, there is no repetition. If the base station decodes / receives preamble 17 associated with SSB#y in the first repetition resource, the base station assumes that there is no repetition associated with the same SSB in the second repetition resource. However, the base station may decode / receive a preamble associated with SSB#y in the second repetition resource. In this case, the base station may recognize the preamble as a preamble from another UE for access. The base station does not need to jointly decode / receive the two preambles.

[0117] In the example of Figure 11A for unit resource 5, according to the above mapping 2, the repeating resource is four ROs. The number of repeats for ROs for SSBs 0 to 40 is two, and the number of repeats for ROs for SSBs 41 to 63 is one. SSBs 0 to 3, SSBs 4 to 7, SSBs 8 to 11, and SSBs 12 to 15 are mapped to the four ROs in the first repeating resource (first time-domain RO), respectively. The same SSBs as those in the first repeating resource are also mapped to the second repeating resource (second time-domain RO). PRACH is repeated in the ROs for the same SSBs in each repeating resource. SSBs 32 to 35, SSBs 36 to 39, SSBs 40 to 43, and SSBs 44 to 47 are mapped to the four ROs in the fifth time-domain RO, respectively. There is no PRACH repetition for these ROs.

[0118] In the example of Figure 11B for unit resource 5, according to mapping 2 above, the repeated resource is four ROs. The repetition number for preamble indexes 0 to 7 for SSB0 is 1, and the repetition number for preamble indexes 8 to 15 for SSB0 is 2. The repetition number for preamble indexes 16 to 23 for SSB1 is 1, and the repetition number for preamble indexes 24 to 31 for SSB1 is 2. The repetition number for preamble indexes 32 to 39 for SSB2 is 1, and the repetition number for preamble indexes 40 to 47 for SSB2 is 2. The repetition number for preamble indexes 48 to 55 for SSB3 is 1, and the repetition number for preamble indexes 56 to 63 for SSB3 is 2.

[0119] SSBs 0 to 3, SSBs 4 to 7, SSBs 8 to 11, and SSBs 12 to 15 are mapped to the four ROs in the first time domain RO, respectively. If preamble index 8 to 15 is used for SSB0, preamble index SSBs 24 to 31 are used for SSB1, preamble index 40 to 47 are used for SSB2, and preamble index 56 to 63 are used for SSB3, the number of repetitions for the first time domain RO is 2. The same SSBs as those in the first repetition resource are also mapped to the second repetition resource (second time domain RO). PRACH is repeated in the ROs for the same SSBs in each repetition resource.

[0120] Variation A1 If the number of SSBs per RO (ssb-perRACH-Occasion) is less than 1, no (additional) repetition resource configuration is required. If repetition is enabled, several ROs mapped to one SSB may be considered as repetition resources. The number of repetitions may be configured.

[0121] In the example of Figure 12A, according to the above-mentioned mapping 1, if OccasionAndCB-PreamblesPerSSB indicates oneHalf,n16 (N=1 / 2, R=16) and msg1-FDM is 4, four ROs are FDMed in one time instance and one SSB is mapped to two ROs (the above-mentioned mapping 1).

[0122] In this example, if repetition is configured, the UE may consider the second RO mapped to each SSB as the second repetition RO for that SSB. In this example, some SSBs / ROs may be configured with a certain repetition number and some SSBs / ROs may not be configured with repetition. In this example, different preambles may be associated with different repetition numbers, including repetition number = 1 (no repetition).

[0123] In the example of Figure 12B, if ssb-perRACH-OccasionAndCB-PreamblesPerSSB indicates oneFourth,n16 (N=1 / 4, R=16) and msg1-FDM is 4, four ROs are FDM'd in one time instance and the four ROs are mapped to one SSB (mapping 2 described above).

[0124] In this example, if repetition is configured and the repetition count is 2, the UE may consider two of the four ROs mapped to each SSB as the second repetition ROs for that SSB. In this example, if repetition is configured and the repetition count is 4, the UE may consider the second, third, and fourth of the four ROs mapped to each SSB as the second, third, and fourth repetition ROs for that SSB, respectively. In this example, different SSBs / ROs may be associated with different repetition counts, including repetition count = 1 (no repetition). In this example, different preambles may be associated with different repetition counts, including repetition count = 1 (no repetition).

[0125] According to this embodiment, the repetition pattern / resource / number of repetitions of the PRACH can be determined appropriately.

[0126] <Third embodiment> In Rel. 15 / 16, the specifications usually map PRACH occasions and SSB indices. There is no definition of PRACH beams in the specifications. However, since beam correspondence is mandatory in Rel. 15, the most likely UE implementation is to use the SSB beam associated with the PRACH occasion. In this case, the base station can use the SSB to receive the PRACH associated with the PRACH occasion. The beam may be a CSI-RS beam.

[0127] This embodiment relates to UE behavior regarding PRACH repeated transmissions.

[0128] For any of the settings of unit resources 1 to 6 described above, the UE may recognize the association between multiple PRACH resources repeated for the same beam. The UE may also recognize which RO is the x-th repeated transmission.

[0129] <<Send operation 1>> For a selected beam (beam determination timing), if the next available RO associated with that beam is not the first repeated transmission RO within the repetition period, the UE may follow one of the following transmission start ROs 1 to 2.

[0130] [Transmission Start RO1] The UE may transmit the same PRACH preamble on ROs associated with the same PRACH preamble repetitions up to the last RO in the repetition period (from the xth repetition to the last repetition). The actual number of repetitions may be less than the maximum number of repetitions (configured / reported) in one repetition period. This behavior may mean that if the base station receives a PRACH preamble in the xth repetition RO associated with an SSB, the base station assumes that it will receive the same preamble in the (x+1)th repetition RO, the (x+2)th repetition RO, etc. This behavior may not mean that the base station must receive the same preamble in the (x+1)th repetition RO, the (x+2)th repetition RO, etc.

[0131] In the example of Figure 13, the number of repetitions is 4. There are four repetitions in one repetition period. If the UE selects SSB0 for PRACH after the second repetition, the UE may transmit the PRACH preamble from the third repetition to the last (fourth) repetition associated with the same PRACH preamble / SSB0.

[0132] [Transmission Begins RO2] The UE may wait until the next repetition period and start transmitting the PRACH preamble on the associated RO from the first repetition RO.

[0133] <<Send operation 2>> For the selected beam, the UE may determine the PRACH resource (RO / preamble) based on the RSRP value, in which case the UE may assume that different PRACH resources are configured with different repetition numbers.

[0134] For example, if threshold 1<=measured RSRP and the channel condition is good, the UE may select a PRACH resource with repetition number=1. Here, if, for the selected SSB#0, preambles 0 to 15 correspond to repetition number=1, preambles 16 to 31 correspond to repetition number=2, and preambles 32 to 47 correspond to repetition number=4, the UE may select one preamble from preambles 0 to 15. In this case, as in the example of Figure 14 (Good RSRP), the UE may select preamble 5.

[0135] For example, if threshold 3<=measured RSRP<threshold 2 and the channel condition is medium, the UE may select a PRACH resource with repetition count=2. Here, the UE may select one preamble from preambles 16 to 31. Threshold 2 may be equal to threshold 1. In this case, as in the example of FIG. 14 (Medium RSRP), the UE may select preamble 20.

[0136] For example, if threshold 5<=measured RSRP<threshold 4 and the channel condition is poor, the UE may select a PRACH resource with repetition number=4, where the UE may select one preamble from preambles 32 to 47. Threshold 4 may be equal to threshold 3.

[0137] In this transmission operation, the UE may take into account (or may regard as) a configured number of repetitions for each PRACH resource.

[0138] In this transmission operation, the UE may consider (or consider as) the remaining actual number of repetitions for each PRACH resource.

[0139] <<Sending operation 3>> When the UE selects a beam for PRACH transmission (from multiple beams), the UE may select the beam according to at least one of the following selection methods 1 to 3 (taking into account at least one parameter of selection methods 1 to 3):

[0140] [Selection method 1] The UE takes into account the RSRP value of each beam, as in existing specifications.

[0141] [Selection method 2] The UE considers the repetition number configured for the PRACH resource associated with each beam in addition to the RSRP value of each beam. For example, for beams with the same repetition number for the PRACH resource, the UE may need to compare the RSRP value of each beam. For example, for beams with different repetition numbers for the PRACH resource and similar RSRP values, the UE may select a beam with an appropriate repetition number based on the RSRP range (similar to transmission operation 2 described above). For example, for beams with different repetition numbers for the PRACH resource and similar RSRP values, the UE may select the beam with the largest repetition number. For example, for beams with different RSRP measurement results and different repetition numbers for the PRACH resource, the UE may select a beam by prioritizing either the RSRP measurement result or the repetition number.

[0142] All SSBs may be configured with the same maximum number of repetitions (so that all beams have the same coverage capability). However, for PRACH resources (ROs / preambles) associated with one SSB, some PRACH resources may be configured with a large number of repetitions and some PRACH resources may be configured with a smaller number of repetitions or no repetitions. UEs accessing any SSB may select PRACH resources corresponding to different numbers of repetitions.

[0143] In Figure 15, the repetition number is 4, and there are four repetition ROs in one repetition period. SSBs 0, 1, 30, and 31 are mapped into each repetition RO. The UE may select an SSB for PRACH by considering SSB 0 and SSB 30, which have the highest RSRP values. Considering that the next RO for SSB 30 is the second repetition RO and the next RO for SSB 0 is the third repetition RO, the UE may select SSB 30, which has the larger number of actual repetitions.

[0144] [Selection method 3] In addition to the RSRP value of each beam, the UE also considers the next available RO repetition order associated with that beam (or the remaining actual number of repetitions associated with each beam). This is similar to selection method 2, except that the actual number of repetitions associated with each beam is considered instead of the configured number of repetitions for each beam. In this case, all SSBs may be associated with the same maximum number of repetitions. At the time the UE selects a beam for access, the remaining actual number of repetitions associated with each beam may be different.

[0145] For example, for some beams above the RSRP threshold, the UE may give the beam with the first repetition RO (second repetition RO, third repetition RO, etc.) as the next available repetition RO associated with a beam having a higher priority than the beam with the second repetition RO (third repetition RO, fourth repetition RO, etc.) as the next available repetition RO associated with the beam. This may mean that the UE selects the beam and its RO with the higher actual repetition number from all beams that meet the RSRP threshold.

[0146] According to this embodiment, the UE can determine the PRACH resource / beam appropriately.

[0147] <Fourth embodiment> This embodiment relates to a counter for the preamble.

[0148] When the second or subsequent repetitions (2nd, 3rd, ...) of the preamble are transmitted, at least one of the following parameters 1 to 3 may be unaffected (not incremented). This may mean that repeated preamble transmissions do not affect the maximum number of transmissions / count / power ramping. [Parameter 1] Preamble transmission counter (PREAMBLE_TRANSMISSION_COUNTER). [Parameter 2] Preamble power ramping (PREAMBLE_POWER_RAMPING_COUNTER). [Parameter 3] Preamble received target power (PREAMBLE_RECEIVED_TARGET_POWER).

[0149] According to this embodiment, the UE can transmit the PRACH repetitions appropriately.

[0150] <Fifth embodiment> This embodiment relates to the number of repetitions in the RACH procedure.

[0151] The influence of the number of PRACH repetitions on the number of repetitions for the remaining RACH procedures may be either of the following influences 1 and 2.

[0152] [Impact 1] The PRACH repetition number influences the repetition numbers for the remaining RACH procedures. At least one of the following repetition numbers 1 to 4 may be derived from the PRACH repetition number: [Repetition number 1] Repetition number of Msg.2. [Repetition number 2] Repetition number of Msg.3. [Repetition number 3] Repetition number of Msg.4. [Number of repetitions: 4] Mg.4 Number of repetitions of HARQ-ACK transmission (PUCCH).

[0153] The mapping between the PRACH repetition and at least one of the repetition numbers 1 to 4 may be configured by higher layer signaling or may be specified in a specification.

[0154] [Impact 2] The number of PRACH repetitions does not affect the number of repetitions for the remaining RACH procedures. At least one of the repetition numbers 1 to 4 may be determined independently of the PRACH repetitions or may be specified.

[0155] According to this embodiment, the UE can appropriately determine the number of repetitions in the RACH procedure.

[0156] According to this embodiment, the UE can transmit the PRACH repetitions appropriately.

[0157] Sixth Embodiment This embodiment relates to Msg.2 / Msg.B.

[0158] For repetition, Msg.2 may follow either of Msg.2 actions 1 and 2 below. [Msg.2 Operation 1] Whether Msg.2 supports repetition may be configured by SIB / RRC or may be configured together with RACH configuration. UE capability regarding Msg.2 repetition may be defined. [Msg.2 Operation 2] Repeated Msg.2 is not supported.

[0159] For repetition, Msg. B may follow either of Msg. B actions 1 and 2 below. [Msg.B operation 1] Whether Msg.B supports repetition may be configured by SIB / RRC or may be configured together with RACH configuration. UE capability regarding Msg.B repetition may be defined. [Msg.B operation 2] Repeated Msg. B is not supported.

[0160] According to this embodiment, the UE can properly receive Msg.2 / Msg.B.

[0161] Seventh Embodiment This embodiment relates to monitoring at least one of Msg.2 and DCI for Msg.2.

[0162] The UE may follow one of the following monitoring actions 1, 2, or 2a to monitor at least one of the DCI with cyclic redundancy check (CRC) scrambled by the RA-RNTI and Msg.2 before sending all PRACH repetitions.

[0163] [Monitoring operation 1] The UE does not monitor at least one of the DCI with CRC scrambled by the RA-RNTI and Msg.2 before sending all PRACH repetitions, which can reduce the power consumption of DCI measurements.

[0164] [Monitoring operation 2] The UE monitors at least one of the DCI with CRC scrambled by the RA-RNTI and Msg.2 before sending all of the PRACH repetitions, which results in faster initial access. After receiving at least one of the DCI with CRC scrambled by the RA-RNTI and Msg.2, the UE may not transmit or may not be required to transmit the remaining PRACH.

[0165] In the example of Figure 16, the number of repetitions of the PRACH is 4. After the second repetition RO, the UE may monitor at least one of the DCI with CRC scrambled by the RA-RNTI and Msg.2.

[0166] [Monitoring behavior 2a] The UE may monitor at least one of Msg.2 and DCI with CRC scrambled by RA-RNTI (if it can / wants to do so) before sending all PRACH repetitions. Even if the base station can detect the first PRACH and sends Msg.2, the base station does not know whether the UE can monitor Msg.2 or not. Therefore, until the base station can receive Msg.3, the base station may send Msg.2, assuming that the UE can monitor at least one of Msg.2 and DCI with CRC scrambled by RA-RNTI after sending all PRACH repetitions.

[0167] According to this embodiment, the UE can properly receive Msg.2.

[0168] Eighth Embodiment In this embodiment, it is assumed that there is no Msg.2 / Msg.B repetition.

[0169] If Msg.1 repetition is configured, the UE / MAC entity may follow at least one of the following window actions 1 to 3 with respect to the ra-ResponseWindow:

[0170] 《Window Operation 1》 The UE / MAC entity starts the ra-ResponseWindow on the first PDCCH occasion from the end of the last actual repeated transmission of the RA preamble, which may be the last repeated RO for the associated SSB within the repetition period. This action may mean that the UE starts monitoring the RAR (which may include monitoring the base station's response to the BFR) after transmitting all repeated preambles.

[0171] 《Window Operation 2》 The UE / MAC entity starts / restarts the ra-ResponseWindow on the first PDCCH occasion from the end of each actual repeated transmission of the RA preamble. This action may mean that the UE monitors the RAR (which may include monitoring the base station's response to the BFR) before completing the transmission of all repeated preambles. Subsequent preamble repetitions may be dropped.

[0172] [Case A] If the ra-ResponseWindow length is smaller than the gap distance between two PRACH preamble repetitions, the ra-ResponseWindow may be considered as three separate windows for RAR monitoring after each PRACH. If an RAR is successfully received within the ra-ResponseWindow, the UE may stop / drop subsequent PRACH / Msg.1 repetitions. If an RAR is successfully received within the ra-ResponseWindow, the UE may stop / drop subsequent PRACH / Msg.1 repetitions after Msg.3 transmission. If an RAR is successfully received within the ra-ResponseWindow, the UE may stop / drop subsequent PRACH / Msg.1 repetitions after Msg.4 reception.

[0173] [Case B] If the ra-ResponseWindow length is greater than the gap distance between two PRACH preamble repetitions, the ra-ResponseWindow may be considered as one window for RAR monitoring after the first actual PRACH transmission with the window restarting after each repeat transmission. If an RAR is successfully received after a PRACH repetition, the UE may stop / drop subsequent preamble repetitions (which may or may not be after Msg.3 / Msg.4). In this case, the UE may also stop the window.

[0174] Using the aforementioned repeat setting of unit resources 2 to 6, the gap distance is very small, and case B may be possible.

[0175] In the example of Figure 17, similar to Figure 15 above, the UE selects SSB30 and starts repeat transmission from the second repeat RO. In the example of window operation 1, the UE starts the ra-ResponseWindow after every repeat (fourth repeat RO). In the example of case A of window operation 2, the UE starts the ra-ResponseWindow after each repeat (second, third, and fourth repeat RO). The length of each ra-ResponseWindow is shorter than the time interval between two repeats. In the example of case B of window operation 2, the UE starts the ra-ResponseWindow after each repeat (second, third, and fourth repeat RO). The length of each ra-ResponseWindow is longer than the time interval between two repeats.

[0176] 《Window Operation 3》 The UE / MAC entity starts the ra-ResponseWindow on the first PDCCH occasion from the end of the first actual repetition of the RA preamble. The window may expire before the UE receives the RAR and before the completion of the PRACH repetition. If the base station sends an RAR after the second PRACH repetition, the UE may not be able to monitor the RAR.

[0177] After the UE starts the ra-ResponseWindow after the first actual iteration, the UE may follow one of the following window actions 3a, 3b, 3c.

[0178] [Window Action 3a] The UE may not assume that the ra-ResponseWindow expires before the end of the last preamble repetition or before a time X (a particular time) after the end of the last preamble repetition.

[0179] [Window Action 3b] If the window expires and the window expiration timing is before the last repeat RO of the SSB associated with the same preamble or before time X after the last repeat RO of the SSB associated with the same preamble, and the UE does not successfully receive the RAR, the UE may restart the window (considering that the ra-ResponseWindow length is not long enough for the last repeat, i.e., the ra-ResponseWindow expires before the end of the last preamble repetition or before time X (a specific time) after the end of the last preamble repetition).

[0180] [Window Action 3c] In the case where, based on window operation 3b, the expiration timing of the window is before the last repeat RO of the SSB associated with the same preamble or before time X after the last repeat RO of the SSB associated with the same preamble, the UE may restart the window after the last repeat in addition to restarting the window after expiration.

[0181] In each of window operations 3a to 3c, if RAR is successfully received after a PRACH repetition, the UE may stop / drop subsequent preamble repetitions (which may or may not be after Msg.3 / Msg.4). In this case, the UE may also stop the window.

[0182] In the example of FIG. 18, similar to FIG. 15 above, the UE selects SSB 30 and starts repeat transmission from the second repeat RO. In the example of windowed operation 3a, the ra-ResponseWindow starts after the first repeat (first repeat RO) and expires a time X after the end of the last repeat (fourth repeat RO). In the example of windowed operation 3b, the ra-ResponseWindow starts after the first repeat (first repeat RO), expires before the end of the last repeat (fourth repeat RO), is restarted, and expires after the last repeat (fourth repeat RO). In another example of windowed operation 3b, the ra-ResponseWindow starts after each repeat and is restarted if it expires before the next repeat. In the last repeat (fourth repeat RO), the ra-ResponseWindow expires a time X after the end of that repeat. In the example of windowed operation 3c, the ra-ResponseWindow starts after the first repeat (first repeat RO), expires before the last repeat (fourth repeat RO), and is restarted. Furthermore, the ra-ResponseWindow is restarted after the end of the last iteration (the fourth iteration RO).

[0183] UE capabilities regarding window operations 1 / 2 / 3 / 3a / 3b / 3c may be defined. UE capabilities regarding whether or not to support restarting a window when it expires or is repeated may be defined.

[0184] Windowing operations 1 / 2 / 3 / 3a / 3b / 3c may be applied to the msgB-ResponseWindow for two-step RACH, where at least one additional symbol of the value of the last symbol of the PRACH occasion corresponding to the PRACH transmission may be taken into account for the start of the window after each PRACH preamble in each windowing operation.

[0185] According to this embodiment, the UE can properly receive Msg.2 / Msg.B.

[0186] <Ninth embodiment> This embodiment relates to the RNTI.

[0187] The RA-RNTI calculation may follow at least one of the following calculation methods 1 to 4.

[0188] 《Calculation method 1》 The RA-RNTI calculation uses the parameters of the first actual PRACH transmission in all repeated ROs. For example, the parameters may include s_id / t_id / f_id. This calculation method can be applied to all window operations in the eighth embodiment.

[0189] In the example of Figure 19A, the number of repetitions is 4, and at least one of DCI with CRC scrambled by RA-RNTI and Msg.2 is associated with the first repetition RO, and RA-RNTI is calculated using parameters of the first actual PRACH transmission.

[0190] 《Calculation method 2》 The RA-RNTI calculation uses the parameters of the last repeated PRACH transmission, which may include, for example, s_id / t_id / f_id. This calculation method can be applied to window operation 1 of the eighth embodiment.

[0191] 《Calculation method 3》 The RA-RNTI calculation uses the parameters of the PRACH transmission of each iteration (latest iteration) before the end of the next repetition RO. For example, the parameters may include s_id / t_id / f_id. This calculation method can be applied to the window operation 2 / 3 of the eighth embodiment.

[0192] In the example of Figure 19B, the number of repetitions is 4, and at least one of DCI with a CRC scrambled by the RA-RNTI and Msg.2 is associated with each repetition RO. The RA-RNTI for the DCI after the last repetition is calculated using the parameters of the last PRACH transmission.

[0193] 《Calculation method 4》 The RA-RNTI calculation takes into account different parameters after the restart of the ra-ResponseWindow. For example, the parameters may include s_id / t_id / f_id. For example, if the window is restarted after a certain iteration, the RA-RNTI calculation may use the parameters of the latest iteration for the RA-RNTI in the subsequent window time. For example, if the window is restarted after the window expires, the RA-RNTI calculation may use the parameters of the latest iteration for the RA-RNTI in the subsequent window time, or the parameters for the RA-RNTI may not be updated in this condition.

[0194] UE capabilities regarding whether to change the RA-RNTI for the window for repetition of PRACH preamble transmission may be defined.

[0195] Different calculation methods among calculation methods 1 to 4 may be applied to multiple window operations in the eighth embodiment, or to different windows in a window operation in the eighth embodiment, or to different durations / lengths of each window in the eighth embodiment.

[0196] Calculation methods 1 to 4 may be applied to the MSGB-RNTI of the two-step RACH.

[0197] According to this embodiment, the UE can properly receive Msg.2 / Msg.B.

[0198] <Tenth embodiment> This embodiment relates to UE capabilities.

[0199] The way in which the UE reports its UE capability regarding support for PRACH repetition may follow either of the following reporting methods 1 and 2.

[0200] 《Reporting method 1》 Different preambles / occasions of the PRACH may be defined for UEs that support PRACH repetition and UEs that do not support PRACH repetition. UEs that do not support PRACH repetition may include Rel. 15 / 16 UEs.

[0201] For UEs that support different numbers (maximum numbers) of PRACH repetitions, different preambles / occasions for the PRACH may be defined.

[0202] By using different preambles / occasions for the PRACH, the base station can recognize whether the UE supports PRACH repetition. The UE may further send additional information about its UE capability of supporting PRACH repetition in Msg.3 or a subsequent RRC IE / MAC CE. For example, the additional information may indicate the maximum number of PRACH repetitions supported by the UE, or whether the UE supports at least one of PRACH repetition in two-step RACH and PRACH repetition in four-step RACH.

[0203] 《Reporting method 2》 The same preamble / occasion of the PRACH may be defined for UEs that support PRACH repetition and UEs that do not support PRACH repetition. UEs that do not support PRACH repetition may include Rel. 15 / 16 UEs.

[0204] The base station cannot determine whether the UE supports PRACH repetition through PRACH measurement. The UE may send additional information about its capability to support PRACH repetition in Msg.3 or a subsequent RRC IE / MAC CE. For example, the additional information may indicate whether the UE supports PRACH repetition, the maximum number of PRACH repetitions supported by the UE, or whether the UE supports at least one of PRACH repetition in two-step RACH and PRACH repetition in four-step RACH.

[0205] According to this embodiment, the UE can transmit the PRACH repetitions appropriately.

[0206] <Other embodiments> 《UE capability information / upper layer parameters》 Higher layer parameters (RRC IEs) / UE capabilities corresponding to the functions (features) in each of the above embodiments may be defined. The higher layer parameters may indicate whether the functions are enabled. The UE capabilities may indicate whether the UE supports the functions.

[0207] A UE for which higher layer parameters corresponding to the function are configured may perform the function. It may also be specified that "a UE for which higher layer parameters corresponding to the function are not configured shall not perform the function (for example, in accordance with Rel. 15 / 16)."

[0208] A UE that reports / transmits a UE capability indicating that it supports the function may perform the function. It may also be specified that "a UE that does not report a UE capability indicating that it supports the function shall not perform the function (e.g., in accordance with Rel. 15 / 16)."

[0209] If the UE reports / transmits a UE capability indicating that it supports the function and the corresponding upper layer parameter is configured, the UE may perform the function. It may also be specified that "if the UE does not report / transmit a UE capability indicating that it supports the function or if the corresponding upper layer parameter is not configured, the UE shall not perform the function (e.g., in accordance with Rel. 15 / 16)."

[0210] Which embodiment / option / choice / function of the above multiple embodiments is used may be configured by higher layer parameters, may be reported by the UE as a UE capability, may be specified in a specification, or may be determined by the reported UE capability and the configuration of higher layer parameters.

[0211] The UE capabilities may indicate whether the UE supports at least one of the following functions: PRACH repetition or PRACH repetition resource configuration. At least one of PRACH repetition in CFRA and PRACH repetition in CBRA. At least one of PRACH repetition in 2-step RACH and PRACH repetition in 4-step RACH. · PRACH repetition in special purpose RA. One or more unit resources from unit resources 1 to 6. -Repeat Msg.2. -Repeat Msg.B. Window operation 1 / 2 / 3 / 3a / 3b / 3c. · Restarting the window if it expires or is repeated. · Changing the RA-RNTI for the window for repetition of PRACH preamble transmission.

[0212] The UE capability may indicate at least one of the following values: · Number of PRACH repetitions (maximum). -Recurrence period setting.

[0213] The above UE capabilities / upper layer parameters allow the UE to achieve the above functions while maintaining compatibility with existing specifications.

[0214] (wireless communication system) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0215] 20 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0216] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0217] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0218] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and the SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0219] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0220] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

[0221] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may be a frequency band higher than FR2.

[0222] Furthermore, the user terminal 20 may perform communication using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

[0223] The multiple base stations 10 may be connected by wire (for example, optical fiber conforming to the Common Public Radio Interface (CPRI), an X2 interface, or the like) or wirelessly (for example, NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0224] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0225] The user terminal 20 may be a terminal compatible with at least one of communication methods such as LTE, LTE-A, and 5G.

[0226] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the radio communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0227] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0228] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0229] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

[0230] The PDSCH transmits user data, higher layer control information, System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit Master Information Block (MIB).

[0231] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

[0232] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as an UL grant, a UL DCI, etc. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

[0233] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources to search for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor a CORESET associated with a certain search space based on the search space configuration.

[0234] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be called a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in the present disclosure may be read interchangeably.

[0235] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), acknowledgement information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0236] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0237] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted as DL-RS.

[0238] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including the SS (PSS, SSS) and the PBCH (and DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as reference signals.

[0239] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0240] (base station) 21 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0241] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0242] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0243] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0244] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0245] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 1211 and an RF unit 122. The receiving unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0246] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0247] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0248] The transceiver 120 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0249] The transceiver 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0250] The transceiver 120 (transmission processor 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0251] The transmitting / receiving unit 120 (RF unit 122) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna .

[0252] On the other hand, the transmitting / receiving unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna .

[0253] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0254] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0255] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0256] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0257] The transceiver 120 may transmit a setting regarding repetition of the physical random access channel, and the controller 110 may control reception of the repetition involving the same beam.

[0258] The transceiver 120 may transmit a configuration for repetition of the physical random access channel. The controller 110 may determine multiple resources for the repetition with the same beam.

[0259] The transceiver 120 may transmit a setting regarding repetition of a physical random access channel in a random access procedure. The control unit 110 may determine, based on the setting, whether to repeat reception or transmission of a channel other than the physical random access channel in the random access procedure.

[0260] The transceiver 120 may receive a setting regarding repetition of a physical random access channel in a random access procedure, and the control unit 110 may determine, based on the setting, whether to repeat reception or transmission of a channel other than the physical random access channel in the random access procedure.

[0261] The transceiver 120 may receive multiple repetitions of the physical random access channel, and the controller 110 may determine a radio network temporary identifier (RNTI) for transmitting a response to the physical random access channel.

[0262] (user terminal) 22 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0263] Note that this example mainly shows functional blocks of the characteristic parts of the present embodiment, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0264] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0265] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 220.

[0266] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured from a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0267] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0268] The transmitting / receiving antenna 230 can be configured as an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0269] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0270] The transceiver 220 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0271] The transceiver 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0272] The transceiver 220 (transmission processor 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0273] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and when transform precoding is not enabled, the transceiver unit 220 may not perform DFT processing as the transmission processing.

[0274] The transmitting / receiving unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna 230.

[0275] On the other hand, the transmitting / receiving unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna 230.

[0276] The transceiver 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

[0277] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurement, CSI measurement, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0278] The transmitting section and receiving section of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving section 220 and the transmitting / receiving antenna 230.

[0279] The transceiver 220 may receive a configuration for repetition of the physical random access channel, and the controller 210 may control the repetition of transmissions involving the same beam.

[0280] The physical random access channel may be within a particular type of random access procedure.

[0281] The recurring resource may be based on any of the period of mapping between the occasions of the physical random access channel and the synchronization signal blocks, the configuration period of the physical random access channel, the time unit, the frequency unit, the occasions, and the synchronization signal blocks.

[0282] The resources may be different from the resources of the non-recurring physical random access channel.

[0283] The transceiver 220 may receive a configuration for repetition of the physical random access channel, and the controller 210 may determine multiple resources for the repetition with the same beam.

[0284] The control unit 210 may determine the resource at which to start the repeated transmission from the plurality of resources based on the timing of determining the synchronization signal block.

[0285] The control unit 210 may determine the plurality of resources based on received power.

[0286] The control unit 210 may change a specific parameter in the first repetition, and may not change the specific parameter in the second or subsequent repetitions.

[0287] The transceiver 220 may receive a setting regarding repetition of a physical random access channel in a random access procedure, and the control unit 210 may determine, based on the setting, whether to repeat reception or transmission of a channel other than the physical random access channel in the random access procedure.

[0288] The control unit 210 may determine the number of repetitions of reception or transmission based on the number of repetitions of the physical random access channel.

[0289] The control unit 210 may determine the number of repetitions of reception or transmission independently of the number of repetitions of the physical random access channel.

[0290] The control unit 210 may receive at least one repetition of message 2 and message B.

[0291] The transceiver 220 may transmit multiple repetitions of the physical random access channel. The controller 210 may control the reception of responses to the physical random access channel.

[0292] The control unit 210 may control receiving the response after the multiple repeated transmissions.

[0293] The control unit 210 may control reception of the response before completion of the multiple repeated transmissions.

[0294] The window for receiving the response may expire a specified time after the multiple repeated transmissions.

[0295] The transceiver 220 may transmit multiple repetitions of the physical random access channel. The controller 210 may determine a radio network temporary identifier (RNTI) for receiving a response to the physical random access channel.

[0296] The control unit 210 may calculate the RNTI based on parameters of a first iteration of the multiple iterations.

[0297] The control unit 210 may calculate the RNTI based on parameters of a last iteration of the multiple iterations.

[0298] The control unit 210 may calculate the RNTI based on parameters of the most recent iteration of the multiple iterations that precedes the end of the next iteration occasion.

[0299] (Hardware configuration) The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0300] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As mentioned above, the implementation method of each is not particularly limited.

[0301] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 23 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0302] In this disclosure, terms such as apparatus, circuit, device, section, unit, etc. may be read interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0303] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0304] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading predetermined software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0305] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transmission / reception unit 120 (220), etc. may be realized by the processor 1001.

[0306] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be realized in a similar manner.

[0307] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, a cache, a main memory, or the like. The memory 1002 may store executable programs (program codes), software modules, and the like for implementing a wireless communication method according to an embodiment of the present disclosure.

[0308] Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as a secondary storage device.

[0309] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0310] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0311] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0312] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using such hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0313] (Variation) Note that terms explained in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0314] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0315] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, a subcarrier spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a transmission time interval (TTI), the number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transceiver in the frequency domain, and a specific windowing process performed by a transceiver in the time domain.

[0316] A slot may be composed of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol), and may be a time unit based on numerology.

[0317] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0318] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0319] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0320] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0321] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0322] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0323] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0324] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0325] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0326] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0327] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0328] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0329] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0330] The BWP may include an UL BWP (a BWP for UL) and a DL BWP (a BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0331] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0332] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0333] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0334] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0335] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0336] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0337] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0338] Notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0339] Note that the physical layer signaling may be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be called an RRC message, such as an RRC connection setup message or an RRC connection reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0340] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0341] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0342] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0343] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0344] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0345] In the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0346] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0347] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0348] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0349] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0350] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

[0351] The mobile body is a movable object that can move at any speed and naturally includes cases where the mobile body is stationary. Examples of the mobile body include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects mounted thereon. The mobile body may also be a mobile body that moves autonomously based on an operation command.

[0352] The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Note that at least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0353] 24 is a diagram showing an example of a vehicle according to an embodiment. A vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, an electronic control unit 49, various sensors (including a current sensor 50, an RPM sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

[0354] The drive unit 41 is configured with at least one of an engine, a motor, and a hybrid of an engine and a motor, for example. The steering unit 42 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by the user.

[0355] The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (e.g., an input / output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

[0356] The signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the current of the motor, a rotation speed signal of the front wheels 46 / rear wheels 47 obtained by a rotation speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 obtained by an air pressure sensor 52, a vehicle speed signal obtained by a vehicle speed sensor 53, an acceleration signal obtained by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 obtained by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 obtained by a brake pedal sensor 56, an operation signal of the shift lever 45 obtained by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 58.

[0357] The information service unit 59 is composed of various devices, such as a car navigation system, an audio system, speakers, a display, a television, and a radio, for providing (outputting) various information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 59 uses information acquired from external devices via the communication module 60 or the like to provide various information / services (for example, multimedia information / multimedia services) to the occupants of the vehicle 40.

[0358] The information service unit 59 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0359] The driving assistance system unit 64 is configured with various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., Global Navigation Satellite System (GNSS)), map information (e.g., High Definition (HD) maps, Autonomous Vehicle (AV) maps), gyro systems (e.g., Inertial Measurement Units (IMUs), Inertial Navigation Systems (INSs)), Artificial Intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driving assistance functions or autonomous driving functions.

[0360] The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 to and from the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and the various sensors 50-58, which are provided in the vehicle 40.

[0361] The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the above-mentioned base station 10 or user terminal 20. Furthermore, the communication module 60 may be, for example, at least one of the above-mentioned base station 10 and user terminal 20 (or may function as at least one of the base station 10 and user terminal 20).

[0362] The communication module 60 may transmit at least one of signals from the above-mentioned various sensors 50-58 input to the electronic control unit 49, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 59 to an external device via wireless communication. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above-mentioned input.

[0363] The communication module 60 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on an information service unit 59 provided in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 60 (or data / information decoded from the PDSCH)).

[0364] Furthermore, the communication module 60 stores various information received from external devices in a memory 62 that can be used by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided in the vehicle 40.

[0365] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, terms such as uplink channel and downlink channel may be read as sidelink channel.

[0366] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0367] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME) and a Serving-Gateway (S-GW)), or a combination thereof.

[0368] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the specific order presented.

[0369] Each aspect / embodiment described in the present disclosure may be a technology other than Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE The present invention may be applied to systems that use 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other appropriate wireless communication methods, or to next-generation systems that are expanded, modified, created, or defined based on these. It may also be applied to a combination of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

[0370] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0371] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0372] The term "determining," as used in this disclosure, may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0373] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0374] Also, "decision" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "decision" may be considered to be "deciding" on some action.

[0375] Furthermore, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," or the like.

[0376] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0377] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0378] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0379] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0380] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0381] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0382] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. A transmitter that repeatedly transmits a random access preamble; A terminal having a control unit that controls a transmission counter, a power ramping counter, and a reception target power of the random access preamble so as not to increment them when transmitting the second or subsequent random access preambles in the repeated transmission.

2. A step of repeatedly transmitting a random access preamble; a step of controlling a transmission counter, a power ramping counter, and a reception target power of the random access preamble so as not to increment them when transmitting the second or subsequent random access preambles in the repeated transmission.

3. A receiver for receiving a random access preamble from a terminal that repeatedly transmits the random access preamble; A base station having a control unit that determines that a transmission counter, a power ramping counter, and a reception target power of the random access preamble are not incremented when the terminal transmits the second or subsequent random access preambles in the repeated transmission.

4. A system having a terminal and a base station, The terminal a transmitter that repeatedly transmits a random access preamble; a control unit that controls a transmission counter of the random access preamble, a power ramping counter, and a reception target power so as not to increment the counter when transmitting a second or subsequent random access preamble in the repeated transmission; The base station A system having a receiver for receiving the random access preamble.

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