Terminal, wireless communication method, and base station

Abstract

Improve coverage by taking overhead into consideration. [Solution] The terminal of the present invention includes a receiving unit that attempts to receive a first synchronization signal block, and a control unit that controls the reception of a second synchronization signal block based on the reception result of the first synchronization signal block, wherein if the reception of the first synchronization signal block fails, the control unit controls the transmission of a preamble using a random access occasion for reporting the failure.

Description

Technical Field

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

Background Art

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

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

[0004] In an existing LTE system (for example, 3GPP Rel. 8-14), a user equipment (UE) transmits uplink control information (UCI) using at least one of a UL data channel (for example, Physical Uplink Shared Channel (PUSCH)) and a UL control channel (for example, Physical Uplink Control Channel (PUCCH)).

Prior Art Documents

Non-Patent Documents

[0005] [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 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Improvements to coverage are being considered for future wireless communication systems (e.g., NR).

[0007] However, narrowing / increasing the beam to improve coverage may increase overhead and reduce communication throughput.

[0008] Therefore, one of the objectives of this disclosure is to provide a terminal, a wireless communication method, and a base station that can improve coverage by taking overhead into consideration. [Means for solving the problem]

[0009] A terminal according to one aspect of the present disclosure includes a receiving unit that attempts to receive a first synchronization signal block, and a control unit that controls the reception of a second synchronization signal block based on the reception result of the first synchronization signal block, wherein if the reception of the first synchronization signal block fails, the control unit controls the transmission of a preamble using a random access occasion for reporting the failure. [Effects of the Invention]

[0010] According to one aspect of this disclosure, coverage can be improved by taking overhead into consideration. [Brief explanation of the drawing]

[0011] [Figure 1] Figures 1A and 1B show examples of beams and coverage. [Figure 2] Figures 2A and 2B show examples of the first SSB and the second SSB. [Figure 3] Figures 3A and 3B show examples of the first and second areas. [Figure 4] Figure 4 shows an example of Embodiment 1-1. [Figure 5] Figure 5 shows an example of an SSB transmission period. [Figure 6] Figure 6 shows an example of Embodiment 1-2. [Figure 7] Figures 7A and 7B show an example of embodiment 1-3. [Figure 8] Figures 8A and 8B show an example of a third embodiment. [Figure 9] Figure 9 shows an example of the fifth embodiment. [Figure 10] Figure 10 shows an example of a QCL relationship. [Figure 11] Figures 11A and 11B show an example of a QCL relationship in DMRS. [Figure 12] Figures 12A and 12B show an example of embodiment 7-1. [Figure 13] Figures 13A and 13B show an example of embodiment 7-2. [Figure 14] Figures 14A and 14B show an example of embodiment 7-3. [Figure 15] Figures 15A and 15B show an example of the first variation of embodiment 7-3. [Figure 16] Figures 16A and 16B show an example of a second variation of embodiment 7-3. [Figure 17] Figure 17 shows an example of coverage. [Figure 18] Figures 18A and 18B show an example of embodiment 8-1. [Figure 19] Figure 19 shows an example of the first variation of Embodiment 8-1. [Figure 20] Figures 20A and 20B are diagrams showing an example of the second variation of Embodiment 8-1. [Figure 21] Figure 21 is a diagram showing an example of the third variation of Embodiment 8-1. [Figure 22] Figure 22 is a diagram showing an example of Embodiment 8-2. [Figure 23] Figures 23A and 23B are diagrams showing an example of Embodiment 8-4-2. [Figure 24] Figure 24 is a diagram showing an example of Embodiment 8-5. [Figure 25] Figure 25 is a diagram showing an example of the ninth embodiment. [Figure 26] Figure 26 is a diagram showing an example of a beam according to the tenth embodiment. [Figure 27] Figure 27 is a diagram showing an example of an SSB beam. [Figure 28] Figure 28 is a diagram showing an example of a variation of an SSB beam. [Figure 29] Figures 29A and 29B are diagrams showing an example of an SSB configuration. [Figure 30] Figures 30A and 30B are diagrams showing an example of Embodiment 10-2. [Figure 31] Figure 31 is a diagram showing an example of Embodiment 10-4-1. [Figure 32] Figure 32 is a diagram showing an example of Embodiment 10-4-2. [Figure 33] Figure 33 is a diagram showing an example of the cyclic shift of a PBCH-DMRS sequence. [Figure 34] Figure 34 is a diagram showing an example of Embodiment 10-4-3. [Figure 35] Figure 35 is a diagram showing an example of the eleventh embodiment. [Figure 36] Figures 36A and 36B are diagrams showing an example of the setting of the repetition number according to the eleventh embodiment. [Figure 37] Figure 37 is a diagram showing an example of the twelfth embodiment. [Figure 38]Figures 38A and 38B show an example of embodiment 12-1. [Figure 39] Figures 39A and 39B show an example of embodiment 12-1-A. [Figure 40] Figures 40A and 40B show an example of embodiment 12-1-B. [Figure 41] Figures 41A and 41B show an example of embodiment 12-2. [Figure 42] Figures 42A and 42B show an example of the 13th embodiment. [Figure 43] Figures 43A-43C show an example of a Msg.3 transmission method. [Figure 44] Figures 44A and 44B show examples of setting the number of repetitions. [Figure 45] Figure 45 shows an example of a schematic configuration of a wireless communication system according to one embodiment. [Figure 46] Figure 46 shows an example of the configuration of a base station according to one embodiment. [Figure 47] Figure 47 shows an example of the configuration of a user terminal according to one embodiment. [Figure 48] Figure 48 shows an example of the hardware configuration of a base station and a user terminal according to one embodiment. [Modes for carrying out the invention]

[0012] (TCI, spatial relations, QCL) In NR, it is being considered to control the receive processing (e.g., at least one of receive, demapping, demodulation, and decoding) and transmit processing (e.g., transmit, mapping, precoding, modulation, and encoding) of at least one of the signal and channel (referred to as signal / channel) at the UE based on the Transmission Configuration Indication state (TCI state).

[0013] The TCI state may represent the one applied to the downlink signal / channel. The equivalent of the TCI state applied to the uplink signal / channel may be expressed as a spatial relation.

[0014] TCI status refers to information about signal / channel quasi-co-location (QCL), and may also be called spatial reception parameters or spatial relation information. TCI status may be set for each channel or signal in the UE.

[0015] QCL is an index that indicates the statistical properties of a signal / channel. For example, if two signals / channels have a QCL relationship, it may mean that we can assume that at least one of the following is identical between these different signals / channels: Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter).

[0016] The spatial reception parameters may correspond to the UE's received beam (e.g., the received analog beam), and the beam may be identified based on the spatial QCL. In this disclosure, QCL (or at least one element of QCL) may be interpreted as sQCL (spatial QCL).

[0017] QCL may have multiple types (QCL types). For example, there may be four QCL types AD that differ in the parameters (or parameter sets) that can be assumed to be the same, and these parameters (which may also be called QCL parameters) are shown 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.

[0018] The assumption by the UE that one control resource set (CORESET), channel, or reference signal is in a specific QCL (e.g., QCL type D) relationship with another CORESET, channel, or reference signal may be called a QCL assumption.

[0019] The UE may determine at least one of the transmit beam (Tx beam) and receive beam (Rx beam) of a signal / channel based on the TCI state or QCL assumption of the signal / channel.

[0020] The TCI state may, for example, be information regarding the QCL between the target channel (in other words, the reference signal (RS) for that channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by upper-layer signaling, physical layer signaling, or a combination thereof.

[0021] The channel / signal to which the TCI status applies may also be called the target channel / reference signal (target channel / RS), or simply the target, while the other signal mentioned above may be called the reference signal (reference RS), source RS, or simply the reference.

[0022] The channel on which the TCI state or spatial relationship is set (specified) may be, for example, at least one of the following: Physical Downlink Shared Channel (PDSCH), Physical Downlink Control Channel (PDCCH), Physical Uplink Shared Channel (PUSCH), or Physical Uplink Control Channel (PUCCH).

[0023] Furthermore, the RS that has a QCL relationship with the channel may be at least one of the following: a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), a Tracking CSI-RS (also called a Tracking Reference Signal (TRS)), a QCL detection reference signal (also called a QRS), or a Demodulation Reference Signal (DMRS)).

[0024] 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 called an SS / PBCH block.

[0025] The RS of a QCL type X in a TCI state may also mean the RS in the relationship between a channel / signal (or its DMRS) and a QCL type X, and this RS may also be called the QCL source of the QCL type X in that TCI state.

[0026] In the TCI state of the DMRS of PDCCH / PDSCH, Type A RS is always set (for both FR1 and FR2), and Type D RS may be set (mainly in FR2).

[0027] Type A RS is used for measuring channel information over long periods, for example, for channel estimation in DMRS. Measuring DMRS only provides instantaneous measurements, so Doppler information cannot be obtained. The UE obtains Type A information {Doppler shift, Doppler spread, mean delay, delay spread} by measuring a periodic RS (e.g., TRS) set as Type A RS, and uses this information to receive PDCCH / PDSCH.

[0028] Type D RS is used to advertise the base station's transmit spatial domain filter (analog beam). The UE selects the UE's receive spatial domain filter by measuring the RS (e.g., TRS) set as Type D RS, and uses this receive spatial domain filter to receive PDCCH / PDSCH.

[0029] (Initial access procedure) In the initial access procedure, the UE (RRC_IDLE mode) receives the SS / PBCH block (SSB), sends Msg.1 (PRACH / Random Access Preamble / Preamble), receives Msg.2 (PDCCH, PDSCH including Random Access Response (RAR)), sends Msg.3 (PUSCH scheduled by the RAR UL grant), and receives Msg.4 (PDCCH, PDSCH including UE contention resolution identity). Subsequently, when the base station (network) sends an ACK to Msg.4 from the UE, the RRC connection is established (RRC_CONNECTED mode).

[0030] SSB reception includes PSS detection, SSS detection, PBCH-DMRS detection, and PBCH reception. PSS detection involves detecting part of the physical cell ID (PCI), detecting (synchronizing) OFDM symbol timing, and (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 (5ms). 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 determining whether the UE can camp in that cell (carrier).

[0031] SSB has a bandwidth of 20 RB and a duration of 4 symbols. The transmission period for SSB can be set from {5, 10, 20, 40, 80, 160} ms. Within a half-frame, multiple symbol positions for SSB are defined based on the frequency range (FR1, FR2).

[0032] A PBCH has a 56-bit payload. N repetitions of the PBCH are transmitted within an 80ms period. N depends on the SSB transmission period.

[0033] System information consists of MIBs carried by PBCH, RMSI (SIB1), and other system information (OSI). SIB1 contains information for RACH configuration and RACH procedures. The time / frequency resource relationship between SSB and PDCCH monitoring resources for SIB1 is set by PBCH.

[0034] A base station using beam correspondence transmits multiple SSBs using multiple beams during each SSB transmission cycle. Each of the multiple SSBs has multiple SSB indices. When a UE detects one SSB, it transmits a PRACH in the RACH occasion associated with that SSB index and receives a RAR in the RAR window.

[0035] (Beam and coverage) In the high-frequency band, if beamforming is not applied to the synchronization / reference signal, coverage becomes narrow, making it difficult for the UE to find the base station. On the other hand, if beamforming is applied to the synchronization / reference signal to ensure coverage, a strong signal will reach in a specific direction, but the signal will be even weaker in other directions (Figure 1A). If the direction of the UE is unknown at the base station before the UE connects, it is impossible to transmit the synchronization / reference signal using a beam only in the appropriate direction. One possible method is for the base station to transmit multiple synchronization / reference signals, each with a beam in a different direction, and for the UE to recognize which beam it has detected. Using a narrow beam for coverage requires transmitting many synchronization / reference signals, which increases overhead and may reduce frequency utilization efficiency.

[0036] Using wider beams (wider beams) to reduce the number of beams (synchronization / reference signals) and thus lower overhead results in narrower coverage (Figure 1B).

[0037] In future wireless communication systems (e.g., 6G), the use of frequency bands such as millimeter waves and terahertz waves is expected to increase further. It is conceivable that communication services could be provided by constructing cell area / coverage using numerous narrow beams.

[0038] Possible approaches include expanding the area using existing FR2 beams and utilizing higher frequency bands than existing FR2 beams. To achieve these goals, improvements in beam management are preferable, in addition to multi-TRP and reconfigurable intelligent surface (RIS) systems.

[0039] In current 5G NR systems, the maximum number of synchronous signal blocks (SSBs) is 64. Because a maximum of 64 beams are needed to cover the cell area (surface), it is difficult to use narrow beams. To utilize a large number of narrow beams, the following beam management methods 1 and 2 are possible.

[0040] [Beam Management Method 1] Using more than 64 SSBs (the maximum number of SSBs exceeds 64). Simply increasing the number of SSBs may increase SSB overhead / initial access latency.

[0041] [Beam Management Method 2] Use up to 64 SSBs (the maximum number of SSBs is 64). Reduce the area (surface) covered by a single cell / sector. Inter-cell / sector interference and high-speed / frequent handovers between cells / sectors may become problems.

[0042] Therefore, the inventors devised a method to suppress overhead / initial access delay.

[0043] The embodiments of this disclosure will be described in detail below with reference to the drawings. Each wireless communication method according to the embodiments may be applied individually or in combination.

[0044] In this disclosure, “A / B / C” and “at least one of A, B, and C” may be interpreted as mutually exclusive. In this disclosure, cell, serving cell, CC, carrier, BWP, DL BWP, UL BWP, active DL BWP, active UL BWP, and band may be interpreted as mutually exclusive. In this disclosure, index, ID, indicator, and resource ID may be interpreted as mutually exclusive. In this disclosure, sequence, list, set, group, cluster, subset, etc. may be interpreted as mutually exclusive. In this disclosure, support, control, controllable, operate, and operable may be interpreted as mutually exclusive.

[0045] In this disclosure, configure, activate, update, indicate, enable, specify, and select may be interpreted as interchangeable.

[0046] In this disclosure, higher-layer signaling may be, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, or a combination thereof. In this disclosure, RRC, RRC signaling, RRC parameter, higher-layer parameter, RRC information element (IE), RRC message, and setting may be interpreted as mutually exclusive.

[0047] MAC signaling may use, for example, MAC Control Elements (MAC CEs) or MAC Protocol Data Units (PDUs). Broadcast information may also include, for example, Master Information Blocks (MIBs), System Information Blocks (SIBs), Remaining Minimum System Information (RMSIs), or Other System Information (OSIs).

[0048] In this disclosure, MAC CE and activation / deactivation commands may be interpreted as interchangeable.

[0049] In this disclosure, beam, spatial domain filter, spatial setting, TCI state, UL TCI state, unified TCI state, unified beam, common TCI state, common beam, TCI assumption, QCL assumption, QCL parameter, spatial domain receive filter, UE spatial domain receive filter, UE receive beam, DL beam, DL receive beam, DL precoding, DL precoder, DL-RS, RS of QCL type D in TCI state / QCL assumption, RS of QCL type A in TCI state / QCL assumption, spatial relationship, spatial domain transmit filter, UE spatial domain transmit filter, UE transmit beam, UL beam, UL transmit beam, UL precoding, UL precoder, PL-RS, antenna port, panel group, beam group may be interpreted as one another. In this disclosure, QCL type X-RS, DL-RS associated with QCL type X, DL-RS having QCL type X, DL-RS source, SSB, CSI-RS, SRS may be interpreted as one another.

[0050] In this disclosure, CSI-RS, NZP-CSI-RS, periodic(P)-CSI-RS, P-TRS, semi-persistent(SP)-CSI-RS, aperiodic(A)-CSI-RS, TRS, CSI-RS for tracking, CSI-RS having TRS information (upper layer parameter trs-Info), NZP CSI-RS resource in an NZP CSI-RS resource set having TRS information, NZP-CSI-RS resource in an NZP-CSI-RS resource set consisting of multiple NZP-CSI-RS resources for the same antenna port, and TRS resource may be interpreted as one another.

[0051] In this disclosure, Msg.1, PRACH, Random Access Preamble, Preamble, and Message may be interpreted as interchangeable. In this disclosure, Msg.2, Msg.2 PDCCH, Random Access Response (RAR), PDSCH including RAR, and Message may be interpreted as interchangeable. In this disclosure, Msg.3, PUSCH scheduled by RAR UL Grant, and Message may be interpreted as interchangeable. In this disclosure, Msg.4, Msg.4 PDCCH, PDSCH including UE contention resolution identity, and Message may be interpreted as interchangeable.

[0052] (Wireless communication method) In this disclosure, failure may be interpreted as failures occurring a specified number of times. The specified number of failures may be defined in the specifications or may be notified / set by broadcast / SIB / upper-layer signaling, etc. The specified number of failures may be 1.

[0053] In this disclosure, beam sweeping, repeated transmission with beam change, and multiple repeated transmissions using different beams may be interpreted as mutually exclusive.

[0054] In this disclosure, the phrases "the SSB (first SSB / second SSB) is not detected / received" and "the received power / received quality of the SSB is below a threshold (or less than a threshold)" may be interpreted interchangeably. In this disclosure, the phrases "the SSB (first SSB / second SSB) is detected / received" and "the received power / received quality of the SSB is above a threshold (or more than a threshold)" may be interpreted interchangeably.

[0055] In this disclosure, broad beam, thick beam, first SSB, first SSB index, PSS / SSS, and PSS / SSS beam may be interpreted as mutually exclusive. In this disclosure, narrow beam, thick beam, second SSB, second SSB index, PBCH / PBCH-DMRS, and PBCH / PBCH-DMRS beam may be interpreted as mutually exclusive.

[0056] <First Embodiment> A first SSB (an existing SSB, 64 SSBs, a first-number SSB) may cover the first area (Figure 2A), and a second SSB (with a different RS than the existing SSB, a second-number SSB) may cover the second area (Figure 2B). A first UE may receive the first SSB, and a second UE may receive the second SSB. The first UE may be an existing (Rel. 15 / 16 NR) UE.

[0057] The first SSB (primary SSB) may be an existing (Rel. 15 / 16 NR) SSB. The first SSB may be transmitted periodically. The first SSB may be the first set of SSBs. The maximum number of first SSBs may be 64.

[0058] The second SSB (secondary SSB) may cover areas not covered by the first SSB. The second SSB may be transmitted periodically or aperiodicly. The second SSB may be the second set of SSBs. The number of second SSBs (second number) may be different from or the same as the number of first SSBs (first number).

[0059] In this disclosure, the second SSB may be an RS other than an SSB, a CSI-RS, or a tracking reference signal (TRS, CSI-RS for tracking).

[0060] In 3D MIMO, each beam constructs an area (plane). The second area covered by the second SSB (Figure 3B) does not necessarily include part or all of the first area covered by the first SSB (Figure 3A).

[0061] The beam used for transmitting the second SSB may be narrower than the beam used for transmitting the first SSB.

[0062] The first SSB and the second SSB may be transmitted on the same carrier / CC / BWP.

[0063] 《Aspect 1-1》 The first SSB may be transmitted periodically.

[0064] The second SSB may be transmitted periodically. If the second SSB is transmitted periodically, the transmission period of the second SSB may differ from the transmission period of the first SSB. The transmission period of the second SSB may be longer than the transmission period of the first SSB.

[0065] The second SSB may be transmitted aperiodically (Figure 4).

[0066] For each first SSB, a specific number of second SSBs may be transmitted. For example, the specific number may be 4, 6, 8, or any other number. If 64 first SSBs are transmitted and the specific number is 6, then 384 second SSBs may be transmitted.

[0067] If the first SSB and second SSB are transmitted periodically, and the transmission period of the second SSB is longer than that of the first SSB (Figure 5), the UE may follow at least one of the following initial access operations 1 and 2.

[0068] [Initial Access Action 1] UEs that can detect the first SSB use the first SSB for initial access. Since the frequency of the first SSB is higher than that of the second SSB, the initial access delay for UEs using the first SSB is small.

[0069] [Initial Access Action 2] UEs that can detect the second SSB use the second SSB for initial access. Since the frequency of the second SSB is lower than that of the first SSB, the initial access delay for UEs using the second SSB is greater than that for UEs using the first SSB. Assuming that most UEs are located within the first area, the impact of the initial access delay can be mitigated.

[0070] 《Aspect 1-2》 The first SSB does not have to be transmitted periodically. A specific number of transmissions (M times) of the first SSB may be repeated at specific time intervals. The specific time interval may be one frame or longer, or 20ms or longer.

[0071] At specific time intervals, M repeated transmissions of the first SSB and N repeated transmissions of the second SSB may occur. The specific time interval may be greater than or equal to the specific period × (M + N).

[0072] Either the first SSB or the second SSB may be transmitted at specific intervals. In the example in Figure 6, SSB transmission opportunities #0 to #4 occur at specific intervals (e.g., 20 ms). At each of SSB transmission opportunities #0 to #2, the first SSB is transmitted, and at each of SSB transmission opportunities #3 to #4, the third SSB is transmitted.

[0073] 《Aspects 1-3》 If the first SSB is transmitted using the first beam and the second SSB is transmitted using the second beam, and the second beam is narrower than the first beam, the number of second SSBs may be greater than the number of first SSBs.

[0074] A first SSB may be transmitted every first period, and a second SSB may be transmitted every second period. The second period may be different from the first period. Multiple first SSBs transmitted in one first period may be called a first SSB set. Multiple second SSBs transmitted in one second period may be called a second SSB set.

[0075] [Aspect 1-3-1] The number of second SSBs (within the second SSB set) per second period is equal to the number of first SSBs (within the first SSB set) per first period.

[0076] All second SSBs (second SSBs corresponding to all second SSB indices) may be transmitted across multiple second cycles (multiple sets of second SSBs). In other words, only some second SSBs (a subset of second SSBs) may be transmitted in each second cycle.

[0077] In each first cycle (each first SSB set), all first SSBs (first SSBs corresponding to all first SSB indices) may be transmitted.

[0078] The transmission duration (duration) of the second SSB in each second cycle may differ from the transmission duration (duration) of the first SSB in each first cycle.

[0079] In the example shown in Figure 7A, the number of first SSBs is 64 and the number of second SSBs is 256. 64 first SSBs are transmitted in each first cycle. 64 different second SSBs are transmitted in each second cycle, resulting in a total of 256 second SSBs transmitted over four second cycles.

[0080] [Aspect 1-3-2] The number of second SSBs (within the second SSB set) per second period is different from the number of first SSBs (within the first SSB set) per first period.

[0081] The transmission duration (duration) of the second SSB signal in each second cycle may differ from the transmission duration (duration) of the first SSB signal in each first cycle. The transmission duration (duration) of the second SSB signal in each second cycle may be longer than the transmission duration (duration) of the first SSB signal in each first cycle.

[0082] In the example shown in Figure 7B, the number of first SSBs is 64 and the number of second SSBs is 256. 64 first SSBs are transmitted in each first cycle. 256 second SSBs are transmitted in each second cycle.

[0083] [Aspect 1-3-3] The subcarrier interval of the second SSB may differ from that of the first SSB. The number of second SSBs (in the second SSB set) per second period may be equal to the number of first SSBs (in the first SSB set) per first period, and the transmission duration (duration) of the second SSB per second period may differ from the transmission duration (duration) of the first SSB per first period. The number of second SSBs (in the second SSB set) per second period may differ from the number of first SSBs (in the first SSB set) per first period, and the transmission duration (duration) of the second SSB per second period may be equal to the transmission duration (duration) of the first SSB per first period.

[0084] The subcarrier interval of the second SSB may be equal to that of the first SSB. The number of second SSBs (in the second SSB set) per second period may differ from the number of first SSBs (in the first SSB set) per first period, and the transmission duration (duration) of the second SSB per second period may differ from the transmission duration (duration) of the first SSB per first period.

[0085] [Aspect 1-3-4] Multiple embodiments from embodiments 1-3-1 to 1-3-3 may be combined. For example, the transmission duration (duration) of the second SSB in each second cycle may be longer than the transmission duration (duration) of the first SSB in each first cycle, and all second SSBs (second SSBs corresponding to all second SSB indices) may be transmitted over multiple second cycles (multiple sets of second SSBs).

[0086] 《Aspects 1-4》 In existing NRs, cell-defined SSB information is communicated through a System Information Block (SIB). Additional SSB information for measurement may be communicated through a MeasObject element.

[0087] At least one of the SIB and servingCellConfig may include information / configurations for the second SSB. At least one of the SIB and servingCellConfig may include information / configurations for the first SSB.

[0088] The UE may use the information of the second SSB, configured / notified by at least one of the SIB and serving cell configurations, to perform the reception / detection / measurement operations of the second SSB (after RRC connection is established / in RRC_CONNECTED mode).

[0089] According to this embodiment, by transmitting a second SSB in addition to the first SSB, coverage can be expanded, overhead can be reduced, and so on.

[0090] <Second Embodiment> 《Aspect 2-1》 The UE may attempt to receive / detect the first SSB, which is transmitted periodically or aperiodically. If the UE has received / detected the first SSB, it may perform initial access using only the first SSB (without using the second SSB). If the UE has received / detected the first SSB, it may perform initial access using either the first SSB or the second SSB. For example, if initial access based on the first SSB fails, the UE may perform initial access using the second SSB.

[0091] If the UE cannot detect the first SSB (for example, if the UE cannot detect the first SSB within the detection time), it may attempt to receive / detect the second SSB. If the UE cannot receive / detect the first SSB, it may perform initial access using only the second SSB (without using the first SSB).

[0092] At least one of the following resource pieces of frequency information 1 and 2, and time information 1 and 2, relating to the second SSB, may be specified in the specification, broadcast, or configured (by upper-layer signaling).

[0093] [Frequency Information 1] The frequency information for the second SSB may be the same as that for the first SSB.

[0094] The frequency information for the second SSB may include the frequency at which the UE searches for the PSS / SSS during initial access (synchronization raster, sync raster). The frequency information for the second SSB may also be specified for each frequency range (FR1, FR2, etc.).

[0095] The frequency at which the UE searches for PSS / SSS, other than during initial access, may be configured / instructed from the network.

[0096] [Frequency Information 2] The frequency information for the second SSB may differ from that of the first SSB. The frequency information for the second SSB may be set / instructed from the network.

[0097] The frequency information for the second SSB may include the relationship between the frequency of the first SSB and the frequency of the second SSB (relative position, frequency offset from the detected RB of the first SSB, etc.).

[0098] [Time Information 1] The time information for the second SSB may be the same as that for the first SSB.

[0099] The time information of the second SSB may include a period (for example, one of several values ​​including at least one of {5, 10, 20, 40, 80, 160}ms). The UE may detect the period blindly.

[0100] [Time Information 2] The time information for the second SSB may differ from that of the first SSB. The time information for the second SSB may be set / instructed from the network.

[0101] The time information of the second SSB may include the relationship between the time of the first SSB and the time of the second SSB (relative position, time offset from the detection symbol of the first SSB, relationship between the period of the first SSB and the period of the second SSB, whether the period of the second SSB is the same as the period of the first SSB, etc.).

[0102] If the UE detects the first SSB and a problem occurs in subsequent actions (e.g., sending Msg.3), it may detect the second SSB and perform subsequent actions based on the second SSB.

[0103] 《Appearance 2-2》 The UE may use the same derivation rules for SSB indices for both the first and second SSBs. The UE can derive frame timings without distinguishing between the first and second SSBs. If the first and second SSBs are transmitted within the same half-frame, the UE may use a method to distinguish all SSB indices for the first and second SSBs (e.g., DMRS sequence, fields / bits in PBCH).

[0104] The UE may use different derivation rules for the SSB index for the first SSB and the second SSB. The UE can distinguish between the first SSB and the second SSB. The number of SSB indices for each of the first and second SSBs can be reduced. The UE may use different frame timing derivation methods for the first SSB and the second SSB.

[0105] According to this embodiment, the UE can properly receive / detect the first SSB / second SSB.

[0106] <Third Embodiment> A UE that detects the first SSB may send PRACH(Msg.1) in the PRACH occasion (RACH occasion) corresponding to the detected first SSB (Figure 8A).

[0107] A UE that does not detect the first SSB (for example, a UE that failed to detect the first SSB within the detection time) may detect the second SSB and send a PRACH in the PRACH occasion corresponding to the detected second SSB (Figure 8B). The correspondence between the second SSB and the PRACH occasion may be defined in the specification, broadcast, or established by upper-layer signaling.

[0108] A UE that has detected the first SSB may then detect the second SSB and send a PRACH in the PRACH occasion corresponding to the detected second SSB.

[0109] A UE that sent a PRACH in a PRACH occasion corresponding to the second SSB may receive a RAR within the random access response (RAR) window corresponding to the second SSB (Figure 8B). The RAR window corresponding to the second SSB may be specified in the specification, broadcast, or established by upper-layer signaling.

[0110] According to this embodiment, the UE can appropriately perform a random access procedure based on the reception of the first SSB or the second SSB.

[0111] <Fourth Embodiment> UEs within the coverage (first area) of the first SSB may follow at least one of the following SSB-related actions 1 and 2.

[0112] [SSB-related operation 1] A UE that can detect the first SSB does not need to detect the second SSB, nor does it need to send a PRACH in the PRACH occasion corresponding to the second SSB. (Especially in contention-based random access (CBRA)) Since there is no need to prepare many PRACH occasions / resources corresponding to the second SSB, PRACH occasions / resources can be distributed.

[0113] [SSB-related operation 2] In a network transmitting a second SSB, a UE capable of detecting the first SSB may either detect the second SSB or transmit a PRACH in the PRACH occasion corresponding to the second SSB. The accuracy of the beam (QCL) information obtained from the second SSB is higher (narrower) than the accuracy of the beam information obtained from the first SSB. By using the beam information from the second SSB, the UE can detect DMRS with higher accuracy compared to using the beam information from the first SSB, and can improve the receiving characteristics of PDSCH / PDCCH and the transmitting characteristics of PUSCH / PUCCH.

[0114] According to this embodiment, the performance of the UE within the coverage of the first SSB can be improved.

[0115] <Fifth Embodiment> This embodiment relates to a QCL relationship using a first SSB and a second SSB.

[0116] QCL relationships using the first and second SSBs may be specified in the specification or notified to the UE. QCL types / QCL chains representing QCL inclusion relationships may be specified in the specification or notified to the UE. One or more second SSBs may be associated with (or contained within) a single first SSB.

[0117] In the example in Figure 9, a first SSB (wide beam) with first SSB index #1-1 and a second SSB (narrow beam) with second SSB indices #2-1 to #2-4 are transmitted. As shown in Figure 10, the QCL relationship of second SSB indices #2-1 to #2-4 points to (references) first SSB index #1-1. If the QCL relationship is type D, the UE can use the received beam (spatial receive parameters, spatial domain receive filter) determined by the reception of first SSB index #1-1 for the reception of second SSB indices #2-1 to #2-4. If the QCL relationship is type A, the UE can use the QCL parameters {Doppler shift, Doppler spread, average delay, delay spread} determined by the reception of first SSB index #1-1 for the reception of second SSB indices #2-1 to #2-4.

[0118] It may also be expressed that the source of a QCL relationship encompasses the target of that QCL relationship. The UE may determine the source of a QCL relationship from the target based on the QCL relationship. For example, the UE may determine the first SSB associated with a detected second SSB and use the first SSB for the channel / RS QCL (beam). The UE may receive not only a narrow beam, but also multiple second SSBs associated with the same first SSB.

[0119] If the QCL source for DMRS#1 of one PDSCH / PDCCH#1 is SSB#1-1, and the QCL source for DMRS#2 of another PDSCH / PDCCH#2 is SSB#2-1, then (especially in FR2) the question for the UE is whether it can receive both PDSCH / PDCCH#1 and PDSCH / PDCCH#2 simultaneously.

[0120] In the example in Figure 11A, the QCL relationship of DMRS#1 refers to TRS#1, and the QCL relationship of TRS#1 refers to SSB#1-1. SSB#1-1, the final reference point of the QCL relationship of DMRS#1, may also be called the root SSB of DMRS#1, the root QCL source, etc. The QCL relationship of DMRS#2 refers to TRS#2, and the QCL relationship of TRS#2 refers to SSB#2-1. SSB#2-1, the final reference point of the QCL relationship of DMRS#2, may also be called the root SSB of DMRS#2, the root QCL source, etc.

[0121] It may be stipulated that if the SSB indices of the root SSBs are different between DMRS#1 and DMRS#2, the UE will assume that DMRS#1 and DMRS#2 are not in a QCL relationship. In this case, if PDSCH / PDCCH#1 and PDSCH / PDCCH#2 are transmitted with the same symbol in FR2, the UE may not receive both.

[0122] Even if the SSB indices of the root SSBs are different between DMRS#1 and DMRS#2, if the QCL source of DMRS#1 and the QCL source of DMRS#2 are in a QCL relationship, the UE may assume that DMRS#1 and DMRS#2 are in a QCL relationship. In this case, as shown in Figure 11B, the beam of the QCL source of DMRS#1 (SSB#1, the first SSB) may include (inclusive of) the beam of the QCL source of DMRS#2 (SSB#2, the second SSB). This case may also be expressed as DMRS#1 and DMRS#2 being in an inclusive QCL relationship. In this case, if PDSCH / PDCCH#1 and PDSCH / PDCCH#2 are transmitted with the same symbol in FR2, the UE may receive both.

[0123] According to this embodiment, the UE can appropriately recognize the QCL relationship between the first SSB and the second SSB.

[0124] <Sixth Embodiment> This embodiment relates to the QCL relationship between the first SSB / second SSB and the DMRS of the PDSCH / PDCCH.

[0125] If a UE transmits a PRACH in a PRACH occasion corresponding to the first SSB / second SSB, the UE may assume that the DMRS of the PDSCH / PDCCH are in a QCL relationship with the first SSB / second SSB corresponding to the PRACH occasion used for transmission.

[0126] The TCI state may be set by upper-layer signaling, and the QCL relationship of the PDSCH / PDCCH DMRS may be set / notified by the TCI state. The first SSB / second SSB may be directly referenced / set as the QCL source for the DMRS TCI state. Another TRS / CSI-RS may be referenced / set as the QCL source for the DMRS TCI state, and the first SSB / second SSB may be referenced / set as the QCL source for this TRS / CSI-RS.

[0127] According to this embodiment, the UE can appropriately utilize the first SSB / second SSB in the QCL relationship of the DMRS of the PDSCH / PDCCH.

[0128] <Seventh Embodiment> One possibility is for the base station to transmit the second SSB only when needed. In this case, it is preferable for the base station to know whether there are any UEs (User Areas) within its UEs that require the second SSB. However, it is difficult for the base station to determine whether a UE can initially access the network using only the first SSB or whether it requires the second SSB.

[0129] This embodiment relates to a second SSB transmission triggered by a UE.

[0130] 《Aspect 7-1》 If the UE detects the first SSB, it may send a PRACH using the PRACH occasion corresponding to the first SSB and receive a RAR in the RAR window (Figure 12A).

[0131] If the UE fails to detect (find) the first SSB (correlation detection fails, or the received power is below a threshold), it may send a dedicated PRACH for detection failure in one or more dedicated PRACH occasions for detection failure notification (Figure 12B). Dedicated PRACH occasions may be specified in the specification or configured by higher-layer signaling.

[0132] A base station that receives a dedicated PRACH may transmit multiple secondary SSBs (while beam sweeping). The UE may measure the received power of the multiple secondary SSBs (while beam sweeping) and transmit a PRACH in the PRACH occasion corresponding to the secondary SSB with the highest received power.

[0133] A UE may transmit multiple dedicated PRACHs in multiple dedicated PRACH occasions. The UE may use different transmit beams for transmitting multiple dedicated PRACHs (it may perform beam sweeping of dedicated PRACHs).

[0134] A base station may attempt to receive multiple dedicated PRACHs in multiple dedicated PRACH occasions. The base station may use different beams (narrow beams) to receive multiple dedicated PRACHs (beam sweeping may be performed). If a dedicated PRACH is detected, a second SSB may be transmitted in the direction of the detected dedicated PRACH (using the beam corresponding to the detected dedicated PRACH).

[0135] A UE that has detected the first SSB and transmitted a dedicated PRACH may then search for the second SSB within a specified period thereafter (by measuring the received power of multiple second SSBs).

[0136] The base station may select a second SSB corresponding to the detected dedicated PRACH occasion and transmit only the selected second SSB.

[0137] 《Appearance 7-2》 The UE may assume that after sending a dedicated PRACH in one or more dedicated PRACH occasions for the first SSB detection failure notification, it will receive the RAR using the resources (beam / RAR window) corresponding to the beam used for the dedicated PRACH (Figure 13A). This eliminates the need to send a second SSB, thus reducing overhead.

[0138] The UE may receive RAR using different receiving beams in multiple RAR windows (while sweeping the receiving beams), as shown in Figure 20A of Embodiment 8-1 described below. In this case, it may be assumed that the UE receives RAR using one or more beams used for dedicated PRACH.

[0139] Multiple RAR windows may be specified in the specification or configured by upper-layer signaling. Multiple RAR windows may correspond to multiple dedicated PRACH occasions / dedicated PRACHs, respectively (Figure 13B). The UE may attempt to receive / measure / detect in the RAR window corresponding to the transmitted dedicated PRACH using the received beam corresponding to the transmitted beam of the transmitted dedicated PRACH.

[0140] 《Aspect 7-3》 Embodiments 7-1 and 7-2 may be combined.

[0141] The UE may transmit a dedicated PRACH in one or more dedicated PRACH occasions, then perform multiple second SSB measurements, and subsequently receive the RAR (Figure 14A). In this case, repeated transmission of the RAR (beam sweeping) may be performed according to embodiment 8-1 described below.

[0142] After transmitting a dedicated PRACH in one or more dedicated PRACH occasions, the UE may select one of several RAR windows based on the reception / measurement / detection of several second SSBs and receive an RAR in the selected RAR window. The selected RAR window may correspond to the second SSB with the highest received power among the received power of several second SSBs. One of the received beams of several second SSBs may correspond to the received beam of the RAR (Figure 14B).

[0143] As shown in Figure 15A, the order in the time domain may be multiple first SSBs, multiple second SSBs, multiple dedicated PRACH occasions, and RAR / RAR windows. One beam of a second SSB may correspond to one beam of a dedicated PRACH occasion / dedicated PRACH and one beam of a RAR.

[0144] As shown in Figure 15B, the order in the time domain may be multiple first SSBs, multiple second SSBs, multiple dedicated PRACH occasions, and multiple RAR windows. A beam of one second SSB may correspond to a beam / occasion of dedicated PRACH and a beam / window of RAR.

[0145] As shown in Figure 16A, the UE may measure multiple secondary SSBs, select one secondary SSB based on the reception / detection / measurement results of the multiple secondary SSBs, select a dedicated PRACH occasion corresponding to the selected secondary SSB from multiple dedicated PRACH occasions, and transmit a dedicated PRACH in the selected dedicated PRACH occasion. Here, the selected secondary SSB may be the secondary SSB corresponding to the highest received power among the received power of the multiple secondary SSBs. The beam of one secondary SSB may correspond to the beam / dedicated PRACH occasion of the dedicated PRACH and the beam / RAR window of the RAR.

[0146] As shown in Figure 16B, the order in the time domain may be multiple first SSBs, multiple second SSBs, multiple dedicated PRACH occasions, and multiple RAR windows. A beam of one second SSB may correspond to a beam / occasion of a dedicated PRACH and a beam / window of a RAR.

[0147] Any of embodiments 7-1 to 7-3 may apply to at least one of the following: initial access, searching for SCells of different frequencies (different frequency bands), UL synchronization, RRC reconfiguration, and recovery from RRC idle. A dedicated PRACH occasion for first SSB detection failure notification may be set by the RRC IE.

[0148] The first SSB, the PRACH occasion corresponding to the first SSB, and the RAR window corresponding to the first SSB may be in the same BWP / CC, or they may be in different BWP / CCs.

[0149] The first SSB, the second SSB, the PRACH occasion corresponding to the second SSB, the RAR window corresponding to the second SSB, and the dedicated PRACH occasion for detection failure notification of the first SSB may be in the same BWP / CC, or they may be in different BWP / CCs.

[0150] According to this embodiment, the overhead of the second SSB can be suppressed.

[0151] <Eighth Embodiment> As shown in the example in Figure 17, it can be assumed that the coverage of Msg.3 (Msg.3 PUSCH, a PUSCH scheduled by the RAR UL grant) is the smallest among the channels / signals during initial access. The UL's transmit power is lower than the DL's transmit power, and Msg.3 has a larger number of information bits compared to PRACH / Msg.4 (PDSCH including UE contention resolution identity) HARQ-ACK, resulting in lower coverage.

[0152] Many UEs' initial Msg.3 transmissions are received correctly, but it is possible that Msg.3s from UEs outside of Msg.3 coverage may be incorrect. The following describes ways to improve the situation for UEs outside of Msg.3 coverage.

[0153] This embodiment may be applied to wireless communication systems in which a second SSB is not transmitted.

[0154] 《Appearance 8-1》 A UE that fails to send the initial Msg.3 may send multiple repetitions of Msg.3. These repetitions may be inter-slot or intra-slot.

[0155] Broadcast / upper layer signaling / Msg.2 (RAR UL grant) / Msg.3 retransmission scheduling allows only configured / instructed UEs to send multiple repetitions of Msg.3 retransmissions.

[0156] A UE that fails to send a certain number of Msg.3 messages (initial / retransmission) may send multiple retransmissions of Msg.3.

[0157] The beam used for Msg.3 retransmission (repeated transmission) may be the same as the beam used for the initial transmission.

[0158] The beam used for Msg.3 retransmission (repetition) may be different from the beam used for the initial transmission. For example, different transmission beams may be used for multiple repetitions (beam sweeping may be used).

[0159] The example in Figure 18A shows a case where the first SSB is received, a PRACH is transmitted in the PRACH occasion corresponding to the first SSB, Msg.2 (RAR) is received, and the first transmission of Msg.3 is successful.

[0160] In the example shown in Figure 18B, if the initial transmission of Msg.3 fails, the UE sends repeated Msg.3 retransmissions.

[0161] If the UE fails to send the initial Msg.3, it may receive a DCI to schedule a retransmission of Msg.3. If Msg.4 is not received within a certain time after the initial Msg.3 is sent, the UE may determine that the initial Msg.3 has failed and send a retransmission of Msg.3 without scheduling it.

[0162] The UE may send multiple repetitions of the Msg.3 initial transmission. As shown in the example in Figure 19, the number of repetitions of the Msg.3 initial transmission may be indicated by a Msg.2 PDCCH / RAR (PDSCH) or a DCI indicating retransmission. The number of repetitions of the Msg.3 initial transmission may be indicated or specified in the specification, as described in aspect 8-2 below.

[0163] When Msg.3 is retransmitted, the second SSB does not need to be transmitted. Multiple repetitions of Msg.2 PDCCH / RAR may be transmitted using different beams (beam sweeping). For example, if the base station recognizes that the reception quality of PRACH is poor, beam sweeping may be performed from Msg.2 PDCCH onwards.

[0164] As shown in the example in Figure 20A, beam sweeping may be used for multiple repetitions of the RAR. The UE transmits Msg.2 PDCCH using the beam of the detected first SSB, and multiple repetitions of the RAR are scheduled by this Msg.2 PDCCH, and beam sweeping may be used for multiple repetitions.

[0165] As shown in the example in Figure 20B, beam sweeping may be used for multiple repetitions of Msg.2 PDCCH and multiple repetitions of RAR. Alternatively, beam sweeping may be used for the repetition of Msg.2 PDCCH, and multiple repetitions of Msg.2 PDCCH may schedule multiple repetitions of RAR, and beam sweeping may be used for the multiple repetitions of RAR.

[0166] As shown in the example in Figure 21, beam sweeping may be used for multiple RAR windows. Multiple RAR windows may be specified in the specification or configured / instructed. The UE may attempt to receive Msg.2 PDCCH and RAR within a RAR window using the beam corresponding to that RAR window. Upon receiving a RAR, the UE may transmit Msg3 using the resources / beam scheduled by that RAR.

[0167] 《Appearance 8-2》 A UE that has sent multiple initial / retransmissions of Msg.3 may attempt to detect Msg.4 on multiple occasions.

[0168] As shown in the example in Figure 22, multiple beams are used for each of the multiple repetitions of Msg.3. Each of the multiple occasions in Msg.4 corresponds to each of the multiple repetitions of Msg.3. Based on the reception / measurement / detection of the multiple repetitions of Msg.3, the base station may select one repetition and transmit Msg.4 using the occasion / beam corresponding to the selected repetition from among the multiple occasions / beams of Msg.4.

[0169] If the UE detects Msg.4 in an occasion, it may use the DL / UL beam corresponding to that occasion for subsequent reception / transmission (it may be assumed that the DL / UL beam corresponding to that occasion is the DMRS and QCL of the PDSCH / PDCCH). This operation ensures a common understanding between the UE and the base station regarding which beams to use.

[0170] 《Appearance 8-3》 This aspect relates to whether multiple repetitions are sent during the initial / retransmission of Msg.3 (number of repetitions, aggregation factor).

[0171] Whether multiple repetitions are sent (number of repetitions) may be specified in the specifications, or it may be notified / configured by broadcast / SIB / upper-layer signaling, etc.

[0172] The number of retransmissions of Msg.3 may be specified in the specifications, or it may be notified / set by broadcast / SIB / upper-layer signaling, etc. Whether multiple retransmissions of Msg.3 are sent (number of retransmissions) may be set separately from whether multiple retransmissions of Msg.3 initial transmissions are sent (number of retransmissions). The number of retransmissions of Msg.3 initial transmissions is not limited to 1. The number of retransmissions of Msg.3 initial transmissions may be specified in the specifications, or it may be notified / set by broadcast / SIB / upper-layer signaling, etc. The number of retransmissions may be changed (increased) depending on the number of times Msg.3 has been transmitted.

[0173] The number of retransmissions for Msg.3 may be greater than the number of retransmissions for the initial Msg.3 transmission. Only UEs that failed the initial Msg.3 transmission can apply a larger number of retransmissions, allowing only necessary UEs to send more retransmissions, thus improving resource utilization efficiency.

[0174] At least one of Msg.2, Msg.3 RAR UL grant, or DCI scheduling a Msg.3 retransmission may indicate whether multiple repetitions of the Msg.3 retransmission will be sent (number of repetitions).

[0175] The base station can operate more flexibly because it can instruct repetition for each UE that transmits Msg.3. For example, the base station can instruct multiple retransmissions of Msg.3 if the received power / quality of the initial Msg.3 transmission is below a threshold, and not instruct multiple retransmissions of Msg.3 otherwise.

[0176] Whether to send multiple repetitions of Msg.3 retransmission may be indicated by a single bit of information or by the number of repetitions. The correspondence between the repetition instruction value (code point) and the number of repetitions may be defined in the specification or may be indicated / set by broadcast / SIB / upper-layer signaling, etc. For example, in the correspondence, the value 00 may correspond to repetition number 1 (transmitted in 1 slot), and the value 01 may correspond to repetition number 2 (transmitted in 2 slots).

[0177] If it is not specified whether to send multiple repetitions of Msg.3 retransmission (number of repetitions), the UE may choose not to send multiple repetitions of Msg.3 retransmission, or it may use the number of repetitions of the initial Msg.3 retransmission as the number of repetitions of Msg.3 retransmission, or it may use a specific number of repetitions (the number of repetitions specified in the specification) as the number of repetitions of Msg.3 retransmission.

[0178] Appearance 8-4 This aspect relates to a method for determining the initial / retransmission beam of Msg.3.

[0179] [Aspect 8-4-1] The initial / retransmit beams for Msg.3 may be specified in the specification, or they may be notified / configured by broadcast / SIB / upper-layer signaling, etc.

[0180] [Aspect 8-4-2] The beam for the initial / retransmission of Msg.3 may be indicated by at least one of Msg.2, the Msg.3 RAR UL grant, and the DCI that schedules the Msg.3 retransmission. The correspondence between the indication value (code point) and the beam ID (RS index) may be defined in the specification or may be notified / set by broadcast / SIB / upper-layer signaling, etc.

[0181] The assignment of beam IDs and the assignment of the number of repetitions may be indicated by common instruction information (fields / bits). For example, as in the example in Figure 23A, if the value of the 2 bits of instruction information is 00 to 01, the number of repetitions may be 2, and if the value of the instruction information is 10 to 11, the number of repetitions may be 4. Each value of the instruction information may be associated with a beam ID for the number of repetitions (beam ID for each repetition).

[0182] The assignment of beam IDs and the assignment of the number of repetitions may be indicated by independent instruction information (fields / bits). For example, as in the example in Figure 23B, each value of the 2-bit first instruction information may be associated with one of the four beam IDs, and the number of repetitions may be indicated / set by a separate second instruction information, or may be specified in the specifications. If the number of repetitions is 2, the first two beam IDs of the four beam IDs indicated by the first instruction information will be used for the first and second repetitions, respectively.

[0183] [Aspect 8-4-3] The initial / retransmission beam for Msg.3 may be determined by the UE. The initial / retransmission beam for Msg.3 may be determined based on rules or may depend on the UE implementation.

[0184] 《Appearance 8-5》 This embodiment relates to the aforementioned embodiment 8-4-1.

[0185] When a UE uses a broad beam (the beam of the first SSB) and a narrow beam (a beam narrower than the beam of the first SSB), the correspondence between the beam ID of the broad beam and the beam ID of the narrow beam may be specified in the specifications, notified / configured by broadcast / SIB / upper-layer signaling, etc., or reported by the UE.

[0186] In the example in Figure 24, spatial relation #1-1 encompasses spatial relations #2-1 through #2-4. For example, if spatial relation #1-1 is used for the initial transmission of Msg.3, spatial relations #2-1 through #2-4 may be used for the retransmission of Msg.3.

[0187] According to this embodiment, the performance of Msg.3 can be improved.

[0188] <Ninth Embodiment> Regarding the relationship between the 2nd SSB and Msg.3.

[0189] The UE may receive / measure / detect the second SSB.

[0190] A UE that detects the first SSB may send Msg.1(PRACH) in the PRACH occasion corresponding to the detected first SSB, receive a RAR in the RAR window corresponding to the first SSB, and send Msg.3 scheduled by the RAR UL grant within that RAR. If an initial access operation based on the first SSB is possible, the UE may perform only the initial access operation based on the first SSB.

[0191] If a specific number of Msg.3 transmission failures occur, either of the following initial access actions 1 or 2 may be followed. A Msg.3 transmission failure may result in a scheduled Msg.3 retransmission, or it may result in the inability to receive Msg.4 within a certain period of time. The specific number of failures may be defined in the specifications, or it may be notified / set by broadcast / SIB / upper-layer signaling, etc. The specific number of failures may be 1.

[0192] [Initial Access Action 1] The UE continues the initial access based on the first SSB and uses the beam corresponding to the detected second SSB for Msg.3 retransmission. Here, the UE may transmit multiple repetitions of Msg.3 retransmission, as in the eighth embodiment. The UE continues the initial access based on the first SSB and uses the beam corresponding to the detected second SSB for Msg.3 retransmission after a specified number of Msg.3 transmission failures.

[0193] [Initial Access Action 2] The UE aborts the initial access based on the first SSB and initiates the initial access based on the detected second SSB. It may send Msg.1 in the PRACH occasion corresponding to the detected second SSB, receive a RAR in the RAR window corresponding to the detected second SSB, and send Msg.3 scheduled by the RAR UL grant within that RAR. Here, the UE may use the beam corresponding to the detected second SSB to send Msg.3.

[0194] The UE is not required to receive / measure / detect all secondary SSBs (it may receive / measure / detect some secondary SSBs). If a QCL relationship (inclusion relationship) between the primary and secondary SSB indices is defined / established, the UE may receive / measure / detect secondary SSB indices that correspond to (are included in) the primary SSB indices. The UE may use the secondary SSB indices that correspond to (are included in) the primary SSB indices used for the beam of the initial transmission of Msg.3 for the beam of the retransmission of Msg.3.

[0195] In the eighth embodiment, the beam from Msg.2 onward may be based on the detected second SSB, or the second SSB corresponding to (incorporating) the detected first SSB.

[0196] The UE may perform initial access after receiving both the first and second SSBs. Alternatively, if initial access based on the first SSB is possible, the UE may perform only initial access based on the first SSB. This improves resource utilization efficiency by limiting the beam sweep of Msg.2 to a minimum number of UEs.

[0197] In the example in Figure 25, the UE detects a first SSB and multiple second SSBs, sends Msg.1 in the PRACH occasion corresponding to the detected first SSB, receives a RAR in the RAR window corresponding to the detected first SSB, and the initial transmission of Msg.3 scheduled by the RAR UL grant in that RAR fails. The UE sends multiple retransmissions of Msg.3. The beams of the multiple retransmissions may each correspond to one of the detected second SSBs. The multiple second SSBs may be associated with (or encompassed by) the detected first SSB.

[0198] According to this embodiment, the performance of initial access / Msg.3 can be improved by using the second SSB.

[0199] <Tenth Embodiment> This concerns the beams used in SSB (First SSB / Second SSB).

[0200] In NR, the SSB transmission cycle is 20ms, and the duration for maintaining PBCH content is 80ms.

[0201] Beam sweeping / beam cycling may be used on at least some specific channels / signals (second signals) of the PSS / SSS / PBCH within the SSB during a specific period. For example, a narrower beam than the first SSB (the beam of the second SSB) may be used for this beam sweeping.

[0202] As shown in Figure 26, if the beam at SSB index #1 encompasses the beams at SSB indexes #1-1 through #1-4, the UE may assume that it can receive narrow beams like SSB indexes #1-1 through #1-4 even when using (assuming) a broad beam like SSB index #1.

[0203] The UE may use a broad beam, such as SSB index #1, to determine the SSB time / frequency, and then use a narrow beam, such as SSB indexes #1-1 to #1-4, to determine SSB indices #1-1 to #1-4.

[0204] For example, a wide beam (SSB index #1) may be used for PSS / SSS (first signal), and a narrow beam (SSB index #1-1 to #1-4) may be used for PBCH-DMRS and PBCH (second signal).

[0205] As shown in Figure 27, a set of SSBs is transmitted every SSB transmission period (e.g., 20 ms), and the PSS / SSS within the SSB at SSB index #1 in each SSB transmission period is transmitted using the same beam (SSB index #1). This prevents a decrease in the detection accuracy of PSS / SSS.

[0206] In multiple SSB transmission cycles within a specific period (e.g., 80 ms) (e.g., four SSB transmission cycles), the PBCH-DMRS and PBCH within the SSB of SSB index #1 may be beam-swept (transmission may be performed using four beams, each with SSB index #1-1 to #1-4).

[0207] As shown in Figure 28, a set of SSBs is transmitted every SSB transmission period (e.g., 20 ms), and the PSS / SSS within the SSB at SSB index #1 in each SSB transmission period is transmitted using the same beam (SSB index #1). This prevents a decrease in the detection accuracy of the PSS / SSS.

[0208] In the first SSB transmission cycle within a specific period (e.g., 100 ms), the PBCH-DMRS and PBCH within the SSB at SSB index #1 may be transmitted using the beam at SSB index #1. In the second and subsequent SSB transmission cycles within a specific period (e.g., the second to fifth SSB transmission cycles), the PBCH-DMRS and PBCH within the SSB at SSB index #1 may be beam-swept (they may be transmitted using the four beams from SSB index #1-1 to #1-4, respectively).

[0209] The UE may assume that, within a single SSB, at least some specific channels / signals of PSS / SSS / PBCH (PBCH-DMRS) and the other channels / signals are not in a QCL relationship.

[0210] As shown in Figure 29A, SSS and PBCH may be transmitted using the same symbol, or as shown in Figure 29B, SSS and PBCH may be transmitted using different symbols.

[0211] 《Appendix 10-1》 This aspect relates to the transmission of Msg.1(PRACH) and the reception of Msg.2 PDCCH / RAR.

[0212] [Aspect 10-1-1] The UE may also transmit Msg.1(PRACH) using a broad beam such as SSB index #1 (a beam encompassing beams from SSB index #1-1 to #1-4).

[0213] A PRACH occasion may correspond to a broad beam, such as SSB index #1. Based on the reception / measurement / detection of a broad beam SSB such as SSB index #1, the UE may select a PRACH occasion corresponding to that SSB and transmit a PRACH in the selected PRACH occasion. The number of PRACH occasions may be the number of broad beam SSBs such as SSB index #1 (e.g., 64).

[0214] The UE may receive Msg.2 PDCCH / RAR using the beam of the SSB index notified using Msg.1 (e.g., SSB index #1).

[0215] [Aspect 10-1-2] The UE may transmit Msg.1(PRACH) using a narrow beam such as SSB indices #1-1 to #1-4 (a beam included in the beam of SSB index #1).

[0216] PRACH occasions may correspond to narrow beams such as SSB indices #1-1 to #1-4. Based on the reception / measurement / detection of SSBs with narrow beams such as SSB indices #1-1 to #1-4, the UE may select a PRACH occasion corresponding to that SSB and transmit a PRACH in the selected PRACH occasion. The number of PRACH occasions may be the number of SSBs with narrow beams such as SSB indices #1-1 to #1-4 (e.g., 64 × 4).

[0217] The UE may receive Msg.2 PDCCH / RAR using the beam of the SSB index notified using Msg.1 (for example, any of SSB indices #1-1 to #1-4).

[0218] 《Aspect 10-2》 This aspect relates to the transmission of Msg.3.

[0219] [Aspect 10-2-1] The UE may transmit Msg.3 using a broad beam such as SSB index #1 (a beam encompassing beams from SSB index #1-1 to #1-4).

[0220] The beam used for transmitting Msg.3 may be the beam notified by Msg.1 in embodiment 10-1-1.

[0221] In embodiment 10-1-2, the UE may include information about narrow beams, such as SSB indices #1-1 to #1-4 (indices in Figure 30A), in Msg.3. This allows the UE to use the narrow beams notified by Msg.3 for transmission and reception after sending Msg.3.

[0222] The UE may signal a narrow beam using other UL channel / UL signals instead of Msg.3.

[0223] After receiving a response to Msg.3 (e.g., Msg.4 PDCCH / PDSCH), the UE may use the narrow beam notified by Msg.3 as QCL information. In other words, the UE may use the narrow beam notified by Msg.3 as a QCL source in transmission and reception after receiving a response to Msg.3.

[0224] The statement that a channel / signal is SSB and QCL (is SSB and QCL) can be interpreted as meaning that it is the SSB and QCL of the SSB index notified by MMsg.3.

[0225] [Aspect 10-2-2] The UE may transmit Msg.3 using a narrow beam such as SSB indices #1-1 to #1-4 (a beam included in the beam of SSB index #1).

[0226] In embodiment 10-1-1, the UE may notify the broad beam information by Msg.1 and include in Msg.3 information about the narrow beam associated with (included in) the broad beam (index in Figure 30B). In this example, the SSB index #x of the broad beam corresponds to the SSB indices #x-1 to #x-4 of the narrow beam.

[0227] The UE may signal a narrow beam using other UL channel / UL signals instead of Msg.3.

[0228] 《Aspect 10-3》 UE does not need to assume QCL between PSS / SSS and PBCH in a single SSB. UE does not need to assume QCL between multiple PBCHs corresponding to the same SSB index within a specific period.

[0229] In embodiment 10-2, the UE may notify of a narrow beam (the beam of the PBCH, the SSB index corresponding to the received beam of the PBCH) by Msg.3.

[0230] Prior to a certain timing (based on the transmission of Msg.3, the reception of Msg.4, or the transmission of a HARQ-ACK in response to Msg.4), a channel / signal being SSB and QCL may also mean that the channel / signal is PSS / SSS and QCL. After that timing, a channel / signal being SSB and QCL may also mean that the channel / signal is PBCH / PBCH-DMRS and QCL.

[0231] 《Appearance 10-4》 The UE may be notified by the PBCH / PBCH-DMRS of information regarding the narrow beam (the beam of the PBCH / PBCH-DMRS) (SSB index). In embodiment 10-2-2, the UE may report this information regarding the narrow beam by Msg.3.

[0232] [Aspect 10-4-1] The beam of the PBCH (narrow beam, SSB indices #1-1 to #1-4) may be indicated in the PBCH by information outside the MIB (e.g., timing-related bits).

[0233] For example, if the beam in Figure 27 is used for PBCH, then, as in the example in Figure 31, four different values ​​(SSB indices #1-1 to #1-4) may be notified in the timing-related fields of the four SSB transmission cycles within a specific period.

[0234] The SSB indices #x-1 to #x-4 of the narrow beam, corresponding to the SSB index #x of the wide beam (PSS / SSS beam), may be communicated in the PBCH by information outside the MIB (e.g., timing-related bits). This reduces the size of the information compared to embodiment 10-4-1.

[0235] The beam cycle period of the PBCH (e.g., a specific period, the number of SSB transmission periods used in the beam cycle, etc.) may be notified by the MIB / SIB.

[0236] [Aspect 10-4-2] The PBCH beam (narrow beam, SSB index #1-1 to #1-4) may be advertised by a PBCH-DMRS sequence. Within a given period, the PBCH-DMRS sequence corresponding to the same broad beam (PSS / SSS beam) may differ for each narrow beam (SSB transmission period). In the PBCH-DMRS sequence, at least one of the following may be associated with the index of the narrow beam: time / frequency resource, cyclic shift index, comb index, and orthogonal cover code (OCC) index.

[0237] The correspondence between the SSB index of PBCH and the PBCH-DMRS sequence may be specified in the specification, broadcast, or set by upper layer signaling. By receiving / confirming / detecting the PBCH-DMRS sequence, the UE can obtain narrow beams (SSB index #1-1 to #1-4) from the received PBCH-DMRS based on the correspondence.

[0238] For example, if the beam in FIG. 27 mentioned above is used for PBCH and the wide beam (the beam of PSS / SSS) is the SSB index #x, as in the example of FIG. 32, the PBCH-DMRS sequences of four SSB transmission periods within a specific cycle may be associated with four different values (SSB index #x-1 to #x-4).

[0239] As in the example of FIG. 33, the cyclic shifts of the PBCH-DMRS sequences of four SSB transmission periods within a specific cycle may be associated with four different values (cyclic shift indices corresponding to SSB index #x-1 to #x-4, PBCH-DMRS sequence indices). The four different values of the cyclic shift index m_CS may be 0, 3, 6, 9.

[0240] [Aspect 10-4-3] The beam of PBCH (narrow beam, SSB index #1-1 to #1-4) may be determined by the rule using the time domain resources of SSB. For example, the rule may determine the SSB index from the SFN and the time position within the frame.

[0241] For example, when the beam in FIG. 27 described above is used for PBCH and the wide beam (the beam of PSS / SSS) is the SSB index #x, as in the example of FIG. 34, a plurality of SSBs (for example, 64 SSBs) within an SSB set for each SSB transmission period are indexed, and a plurality of SSB sets (for example, 4 SSB sets) from a reference point (for example, the start point such as a frame, a specific period (for example, 4 SSB transmission periods), a specific number (for example, 4) of SSB transmission periods, etc.) may be indexed. The SSB index #x-i of the PBCH beam may be subjected to a mod operation (for example, mod 4) for each specific number of SSB transmission periods.

[0242] 《Aspect 10-5》 In the procedure (transmission / reception of a certain channel / signal) after the UE notifies the SSB index, when using the SSB index, that a certain channel / signal is QCL with the SSB having that SSB index may follow at least one of the following Interpretations 1 and 2. [Interpretation 1] The UE uses the PSS / SSS of that SSB as the QCL source of that channel / signal. [Interpretation 2] The UE uses the PBCH-DMRS of that SSB as the QCL source of that channel / signal.

[0243] The UE may follow either of the following QCL application methods 1 and 2.

[0244] [QCL Application Method 1] The UE may use Interpretation 1 before a certain timing (the timing based on Msg.3 transmission, or Msg.4 reception, or HARQ-ACK transmission for Msg.4) as described in Aspect 10-3, and use Interpretation 2 after that timing. A certain timing may be after a specific time (a specific number of symbols / a specific number of slots) has elapsed from Msg.3 transmission, or Msg.4 reception, or HARQ-ACK transmission for Msg.4.

[0245] [QCL Application Method 2] For each channel / RS to which QCL is applied (target), whether to use interpretation 1 or 2 may be specified in the specification, broadcast, or configured / instructed.

[0246] Along with beam indications such as TCI status / QCL information, either interpretation 1 or 2 may be set / indicated.

[0247] For example, for individual UE channels / RS, a narrow beam is preferred, so interpretation 2 may be used. For example, for a common UE channel / RS, repeated transmission of many beams would be overhead, so interpretation 1 may be used.

[0248] According to this embodiment, the UE can appropriately determine the beam used for SSB / channel / signal.

[0249] <Embodiment 11> Repeat transmission may be notified / configured by broadcast / upper-layer signaling. A notified / configured UE may apply repeat transmission to a specific type of channel / RS (Figure 35). The same number of repetitions may be applied to all notified / configured UEs.

[0250] A specific type of channel / RS may be a channel / RS for multiple types of DL / ULs, or it may be a channel / RS for all DL / ULs.

[0251] A single repetition count (aggregation factor) may be set for a specific type of channel / RS.

[0252] Multiple repetition counts may be set for multiple types of channels / RS. Alternatively, the repetition count may be set for each type of channel / RS.

[0253] The number of repetitions may be specified in the specification, notified / set by broadcast / MIB / SIB, notified / set by UE-specific upper-layer control information (RRC IE), or based on a value reported by UE capability signaling. For example, UEs with low transmit / receive performance may use a larger number of repetitions, while UEs with higher performance may use a smaller number of repetitions.

[0254] The method for setting the number of repetitions may also follow the method described in Actual 2-2 below.

[0255] Several patterns of repetition counts may be defined / configured. One of these patterns may be indicated by broadcast / upper layer signaling / MAC CE / physical layer control information. An example in Figure 36A shows a case where one repetition count is set / indicated for multiple types of channels / RS. When settings #1 to #4 are set and one of settings #1 to #4 is indicated, the UE applies the repetition count corresponding to the indicated setting to the multiple types of channels / RS. An example in Figure 36B shows a case where one repetition count is set / indicated for each type of channel / RS. When settings #1 to #4 are set and one of settings #1 to #4 is indicated, the UE applies the repetition count corresponding to the channel / RS (PUSCH / PUCCH / PDSCH) from the indicated setting to that channel / RS.

[0256] According to this embodiment, coverage can be improved by repeated transmission.

[0257] <Twelfth Embodiment> Repeat transmission may be notified / configured by broadcast / upper-layer signaling. The notified / configured UE may, if necessary (depending on the conditions), apply repeat transmission to specific types of channels / RS (Figure 37).

[0258] A specific type of channel / RS may be a channel / RS for multiple types of DL / ULs, or it may be a channel / RS for all DL / ULs.

[0259] When the applicable conditions are met, the UE may apply repeated transmission to a specific type of channel / RS.

[0260] The number of repetitions may be set for each type of channel / RS. The number of repetitions may be set for multiple types of DL / UL channels / RS.

[0261] The number of repetitions may be notified / set by broadcast / MIB / SIB, or may be notified / set by UE individual upper layer control information (RRC IE).

[0262] The number of repetitions may be determined based on a determination rule.

[0263] If the UE has successfully detected PSS / SSS (the received power of PSS / SSS is above the threshold) but failed to read the MIB, the determination rule may determine the number of repetitions based on the number of failures in reading the MIB. For example, when the number of failures is 0, the number of repetitions is 1 (no repeated transmission is performed), and when the number of failures is 4, the number of repetitions is 4.

[0264] The determination rule may determine the number of repetitions based on the number of transmission failures of Msg.3. For example, the number of repetitions for the first transmission of Msg.3 is 1, the number of repetitions for the first retransmission of Msg.3 is 2, and the number of repetitions for the second retransmission of Msg.3 is 3.

[0265] The correspondence between the number of failures in reading the MIB, the number of transmission failures of Msg.3, etc. and the number of repetitions may be specified in the specification, may be set by upper layer signaling, or may be reported by UE capability signaling.

[0266] The problem is when the determined number of repetitions is applied.

[0267] The UE may apply the determined number of repetitions to a specific type of channel / RS immediately after the application conditions are met. The UE may apply that number of repetitions to a specific type of channel / RS that is triggered / scheduled after the application conditions are met. The UE may apply that number of repetitions to a specific type of channel / RS that is transmitted / received after the application conditions are met.

[0268] The UE may apply the determined number of repetitions to a specific type of channel / RS after a waiting period (e.g., X symbols / X slots / Y [ms]) has elapsed since the application conditions were met. The UE may apply the number of repetitions to a specific type of channel / RS that is triggered / scheduled after a waiting period has elapsed since the application conditions were met. The UE may apply the number of repetitions to a specific type of channel / RS that is transmitted / received after a waiting period has elapsed since the application conditions were met.

[0269] Waiting time may be specified in the specifications, set by higher-layer signaling, or reported by UE capability signaling.

[0270] The UE may, after the applicable conditions are met, explicitly or implicitly notify of a repeat transmission and, based on that notification, apply a determined number of repeats to a specific type of channel / RS. Repeat transmission of UL is possible if the UE determines that a repeat transmission is necessary. Repeat transmission of DL is also possible by the UE notifying the base station that a repeat transmission is necessary.

[0271] The UE may explicitly send a request / instruction / notification for retransmission in the first UL transmission after the applicable conditions are met. The UE may implicitly send a request / instruction / notification for retransmission by repeating the first UL transmission after the applicable conditions are met.

[0272] 《Aspect 12-1》 The UE may determine the number of repetitions / repetitions. The applicable conditions may be at least one of the following conditions, or an AND / OR of multiple conditions from the following conditions. • The received power / quality of a specific SSB is below a threshold (for example, the specific SSB may be the SSB corresponding to the best received power / quality among 65 SSBs). • The UE fails to send Msg.1 (PRACH) within a specified period (time) (the UE does not receive Msg.2 within a specified period (time)). The UE fails to receive Msg.2 (PDCCH / RAR) within a specified period (time). • The UE fails to send Msg.3 (PUSCH scheduled by the RAR UL grant) within a specified period (time) (either the UE does not receive Msg.4 within the specified period, or the UE is instructed to retransmit Msg.3). • The UE fails to receive Msg.4 within a specified period (time). • The UE fails to send Msg.4 HARQ-ACK within a specified period (time). (The UE is instructed to receive a Msg.4 retransmission within a specified period (time). The UE makes the decision based on its implementation (the UE decides to repeatedly send Msg.1 / Msg.3 / Msg.4 HARQ-ACK based on SSB reception, etc.). A UE that has repeatedly sent Msg.1 / Msg.3 / Msg.4 HARQ-ACK may apply the repeated transmission to specific types of channels / RS in subsequent initial access procedures / operations after RRC connection establishment. The UE may also send a request / desired number of repetitions to the base station. • The UE fails to send Msg.A (PRACH / PUSCH) within a specified period (time) (either the UE does not receive Msg.B within the specified period, or Msg.B schedules the transmission of Msg.3 (fallback indication)). The UE fails to receive Msg.B (PDCCH / PDSCH) within a specified period (time). The UE successfully reads the MIB, but fails to receive at least one of the following: SIB1 PDSCH and the PDCCH (CORESET#0 / SearchSpace#0) that schedules it.

[0273] As shown in Figure 38A, if the application conditions are not met (i.e., the initial transmission of Msg.3 is successful), the UE does not need to apply repeated transmission to a specific type of channel / RS thereafter (it may apply a repeat count of 1).

[0274] As shown in Figure 38B, if the applicable conditions are met (i.e., if the initial transmission of Msg.3 fails), the UE may apply repeated transmission to a specific type of channel / RS (e.g., a Msg.3 retransmission) (it may apply a number of repetitions greater than 1). The UE may use different beams for each of the multiple repetitions (it may use beam sweeping), or it may use the same beam for multiple repetitions.

[0275] The relationship between the application conditions and the number of repetitions will be explained below.

[0276] [Aspect 12-1-A] The correspondence between application conditions and the number of repetitions may be defined in the specification, or it may be notified / configured by broadcast / upper-layer signaling. The UE may use the correspondence to determine the number of repetitions corresponding to the application conditions and apply that number of repetitions to a specific type of channel / RS.

[0277] In the examples in Figures 39A and 39B, the application conditions are defined by the range of the SSB RSRP value P. The boundary values ​​P_0, P_1, and P_2 may be specified in the specification or notified / set by broadcast / upper-layer signaling.

[0278] In the example in Figure 39A, the number of repetitions is defined for one or more specific types of channels / RS. In the example in Figure 39B, the number of repetitions is defined for each type of channel / RS (PUSCH / PUCCH / PDSCH). Since the coverage differs for each channel / RS, the required number of repetitions may also differ. For example, the receive (transmit) power of DL is greater than that of UL, and the larger the payload size, the smaller the coverage. The type of channel / RS may also be the type of message / content. The type of message / content may be Msg.2 / 3 / 4, etc.

[0279] Embodiment 12-1 may be applied before the RRC connection is established, and after the RRC connection is established, the number of repetitions may be set by the RRC IE.

[0280] [Aspect 12-1-B] Multiple settings / candidates for the number of repetitions requested / reported by UL transmission (e.g., Msg.3) may be specified in the specification or notified / configured by broadcast / upper-layer signaling. The UE may determine the number of repetitions from multiple settings. The UE may request / report the determined number of repetitions by Msg.3 and apply it to a specific type of channel / RS after acknowledging receipt of Msg.3 (receiving Msg.4 PDCCH or Msg.4(PDSCH)).

[0281] In the example in Figure 40A, multiple settings / candidates for the number of repetitions are specified / configured for one or more specific types of channels / RS. In the example in Figure 40B, multiple settings / candidates for the number of repetitions are specified / configured for each type of channel / RS (PUSCH / PUCCH / PDSCH). Since the coverage differs for each channel / RS, the required number of repetitions may also differ. For example, the receive (transmit) power of DL is greater than the receive (transmit) power of UL, and the larger the payload size, the smaller the coverage. The type of channel / RS may also be the type of message / content. The type of message / content may be Msg.2 / 3 / 4, etc.

[0282] Embodiment 12-1 may be applied before the RRC connection is established, and after the RRC connection is established, the number of repetitions may be set by the RRC IE.

[0283] 《Aspect 12-2》 The base station (network) may determine the number of repetitions. The UE may instruct / configure repetitions by at least one of Msg.2 PDCCH / RAR, Msg.4, Msg.B PDCCH / PDSCH, and upper-layer signaling.

[0284] Multiple repetition count settings / candidates, indicated / set by DL transmission (at least one of Msg.2 PDCCH / RAR, Msg.4, Msg.B PDCCH / PDSCH, and upper-layer signaling), may be specified in the specification or notified / set by broadcast / upper-layer signaling. A base station may notify / instruct / set one of the multiple repetition count settings by DL transmission. A UE may apply the notified repetition count to a specific type of channel / RS.

[0285] In the example in Figure 41A, multiple settings / candidates for the number of repetitions are specified / configured for one or more specific types of channels / RS. In the example in Figure 41B, multiple settings / candidates for the number of repetitions are specified / configured for each type of channel / RS (PUSCH / PUCCH / PDSCH). Since the coverage differs for each channel / RS, the required number of repetitions may also differ. For example, the receive (transmit) power of DL is greater than the receive (transmit) power of UL, and the larger the payload size, the smaller the coverage. The type of channel / RS may also be the type of message / content. The type of message / content may be Msg.2 / 3 / 4, etc.

[0286] According to this embodiment, the UE can appropriately apply repeated transmission.

[0287] <13th Embodiment> Coverage may be expanded by repeated transmission of SSB. Coverage may be expanded for channels / RS other than SSB (e.g., individual UE channels / RS) using narrower beams than SSB. Repeated transmission is not required for channels / RS other than SSB whenever possible.

[0288] The repeated transmission of SSB signals, transmitted periodically, has little impact on system overhead. On the other hand, the repeated transmission of individual UE channels / RS signals has a significant impact on system overhead.

[0289] As shown in the example in Figure 42A, a signal using a wide beam (e.g., a wide-beam SSB, the first SSB) may have its coverage expanded by being combined and received. The UE may obtain a combined gain by combining and receiving a specific number (e.g., four) SSBs. As shown in the example in Figure 42B, a signal using a narrow beam (e.g., a narrow-beam SSB, the second SSB) may have its coverage expanded by narrowing the beam. In the examples in Figures 42A and 42B, one wide beam corresponds to (contains) four narrow beams. The narrow beams are beam swept, and a different beam (SSB indices #1 to #4) is used for each period. In this example, the narrow-beam second SSB is transmitted in a different frame / slot than the wide-beam first SSB, but they may be transmitted in the same frame / slot. Similar to the tenth embodiment, within a single SSB, PSS / SSS and PBCH / PBCH-DMRS may be transmitted using different beams.

[0290] If the application conditions in the twelfth embodiment are met, the UE may request a narrow beam (e.g., a second SSB) as the QCL source for a particular type of channel / RS. The UE may follow either of the following beam application operations 1 and 2.

[0291] [Beam application operation 1] If the applicable conditions are met (for example, if the received power / quality of the SSB is below a threshold), the UE may request / report repeated transmission as in Embodiment 12-1-B and apply a narrow beam to the QCL source of a specific type of channel / RS. The UE may determine the number of repetitions and also select / determine the beam to apply to those repetitions. A wide beam (first SSB) may be applied to channels / RS to which repeated transmission is not applied. A narrow beam (second SSB) may be applied to channels / RS to which repeated transmission is applied. The number of repetitions for channels / RS using a narrow beam may be less than the number of repetitions for channels / RS using a wide beam.

[0292] [Beam application operation 2] If the applicable conditions are met (for example, if the received power / quality of SSB is below a threshold), the UE may apply a narrow beam to a QCL source of a specific type of channel / RS without requesting / reporting repeated transmissions as in Embodiment 12-1-B.

[0293] Beam application operations 1 and 2 reduce the resources required for repeated transmission, thereby improving resource utilization efficiency.

[0294] The narrow beam may be one of several second SSBs associated with (contained by) the received first SSB. The method for selecting the narrow beam may be specified in the specification or may be notified / configured by PBCH / SIB1 / broadcast / upper layer signaling.

[0295] The channel / RS to which a narrow beam is applied may be all channels / RS.

[0296] The channels / RS to which narrow beam is applied may be of a specific type. This specific type may be an RS, a data channel, a control channel, or a channel with a payload size above a certain level. For channels / RS other than the specific type, repeated transmission may be applied, or neither repeated transmission nor narrow beam may be applied.

[0297] Figure 43A shows an example of the 11th / 12th embodiment. When the applicable conditions are met (the received power / quality of the detected SSB is below a threshold), the UE may transmit a PRACH in the PRACH occasion corresponding to the SSB, receive Msg.2 in the RAR window, and transmit multiple repetitions of Msg.3 using a broad beam. Different broad beams may be used for the multiple repetitions. The SSB may be a first SSB. Different broad beams may be associated with different first SSBs.

[0298] Figure 43B shows an example of beam application operation 1. If the application conditions are met (the received power / quality of the detected SSB is below the threshold), the UE may transmit a PRACH in the PRACH occasion corresponding to the SSB, receive Msg.2 in the RAR window, and transmit multiple repetitions of Msg.3 using a narrow beam. Different narrow beams may be used for the multiple repetitions. The SSB may be the first SSB. Different narrow beams may be associated with different second SSBs associated with that first SSB.

[0299] Figure 43C shows an example of beam application operation 2. If the application conditions are met (the received power / quality of the detected SSB is below the threshold), the UE may transmit a PRACH in the PRACH occasion corresponding to the SSB, receive Msg.2 in the RAR window, and transmit Msg.3 (non-repeated transmission) using the narrow beam. The SSB may be the first SSB. The narrow beam may be associated with one of several second SSBs associated with that first SSB.

[0300] In embodiments 12-1-A, 12-1-B, and 12-2, in addition to the number of repetitions, whether to use a wide beam or a narrow beam may also be set. For example, in the example in Figure 44A, the number of repetitions and whether to use a wide beam or a narrow beam may be associated with each setting in Figure 14A of embodiment 12-2. For example, in the example in Figure 44B, the number of repetitions and whether to use a wide beam or a narrow beam may be associated with each setting in Figure 14B of embodiment 12-2.

[0301] <Other Embodiments> 《UE Abilities / Higher Layer Parameters》 A higher-layer parameter (RRC information element) / UE capability may be defined corresponding to at least one function (feature) in each embodiment. The UE capability may indicate whether or not it supports this function.

[0302] A UE that has the corresponding higher-layer parameters set may perform that function. It may also be stipulated that "a UE that does not have the corresponding higher-layer parameters set will not perform that function (for example, apply the behavior of Rel.15 / 16)."

[0303] A UE that has reported UE capability indicating support for that function may perform that function. It may also be stipulated that "a UE that has not reported UE capability indicating support for that function shall not perform that function (for example, apply the behavior of Rel. 15 / 16)."

[0304] If the UE reports its capability to support the function and the corresponding higher-layer parameters are set, the UE may perform the function. It may also be stipulated that "if the UE does not report its capability to support the function, or if the corresponding higher-layer parameters are not set, the UE will not perform the function (for example, apply the behavior of Rel. 15 / 16)."

[0305] UE capability may indicate whether or not it supports the second SSB.

[0306] UE capability may indicate whether a single QCL source / RS index supports being associated with multiple QCL source / RS indexes (i.e., encompassing multiple QCL source / RS indexes).

[0307] Based on the above UE capabilities / higher layer parameters, the UE can achieve the above functions while maintaining compatibility with existing specifications.

[0308] (Wireless communication system) The configuration of a wireless communication system according to one embodiment of this disclosure will be described below. In this wireless communication system, communication is performed using any or a combination thereof of the wireless communication methods according to the above embodiments of this disclosure.

[0309] Figure 45 shows an example of a schematic configuration of a wireless communication system according to one embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE), 5th generation mobile communication system New Radio (5G NR), etc., as specified by the Third Generation Partnership Project (3GPP).

[0310] Furthermore, the wireless communication system 1 may 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)), and so on.

[0311] 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.

[0312] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity where both MN and SN are NR base stations (gNB) (NR-NR Dual Connectivity (NN-DC))).

[0313] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with relatively wide coverage, and base stations 12 (12a-12c) located within the macrocell C1 that form a small cell C2 that is narrower than the macrocell C1. User terminals 20 may be located within at least one cell. The arrangement and number of each cell and user terminal 20 are not limited to the configuration shown in the figure. Hereinafter, when base stations 11 and 12 are not distinguished, they will be collectively referred to as base station 10.

[0314] 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).

[0315] Each CC may be included in at least one of the first frequency band (Frequency Range 1 (FR1)) and the second frequency band (Frequency Range 2 (FR2)). A macrocell C1 may be included in FR1, and a 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 fall in a frequency band higher than FR2.

[0316] Furthermore, the user terminal 20 may communicate using at least one of the following methods at each CC: Time Division Duplex (TDD) and Frequency Division Duplex (FDD).

[0317] Multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with Common Public Radio Interface (CPRI), X2 interface, etc.) or wireless (e.g., NR communication). For example, if NR communication is used as a backhaul between base stations 11 and 12, base station 11, which is the upstream station, may be called an Integrated Access Backhaul (IAB) donor, and base station 12, which is the relay station, may be called an IAB node.

[0318] Base station 10 may be connected to the core network 30 via other base stations 10 or directly. The core network 30 may include at least one of the following: Evolved Packet Core (EPC), 5G Core Network (5GCN), Next Generation Core (NGC), etc.

[0319] The user terminal 20 may be a terminal that supports at least one of the following communication methods: LTE, LTE-A, 5G, etc.

[0320] In the wireless communication system 1, an orthogonal frequency division multiplexing (OFDM)-based wireless access scheme may be used. 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), etc., may be used in at least one of the downlink (DL) and uplink (UL).

[0321] The wireless access method may also be called a waveform. In wireless communication system 1, other wireless access methods (for example, other single-carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL wireless access methods.

[0322] In the wireless communication system 1, a Physical Downlink Shared Channel (PDSCH), a Broadcast Channel (PBCH), or a Physical Downlink Control Channel (PDCCH) may be used as the downlink channel, shared by each user terminal 20.

[0323] Furthermore, in the wireless communication system 1, the uplink channel may include a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH), or the like, all of which are shared by each user terminal 20.

[0324] User data, higher-layer control information, and System Information Blocks (SIBs) are transmitted via PDSCH. User data and higher-layer control information may also be transmitted via PUSCH. Furthermore, Master Information Blocks (MIBs) may be transmitted via PBCH.

[0325] Lower-layer control information may be transmitted by PDCCH. The lower-layer control information may include, for example, Downlink Control Information (DCI) which includes scheduling information for at least one of PDSCH and PUSCH.

[0326] Furthermore, the DCI that schedules PDSCH may be called a DL assignment or DL ​​DCI, and the DCI that schedules PUSCH may be called a UL grant or UL DCI. Furthermore, PDSCH may be interpreted as DL data, and PUSCH may be interpreted as UL data.

[0327] PDCCH detection may utilize a Control Resource Set (CORESET) and a search space. A CORESET corresponds to the resources used to search for DCIs. A search space corresponds to the search area and search method for PDCCH candidates. A single CORESET may be associated with one or more search spaces. The UE may monitor CORESETs associated with a particular search space based on the search space configuration.

[0328] A single search space may correspond to one or more PDCCH candidates corresponding to aggregation levels. One or more search spaces may be referred to as a search space set. In this disclosure, "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," and "CORESET configuration" may be interpreted interchangeably.

[0329] PUCCH may transmit uplink control information (UCI) which includes at least one of the following: channel state information (CSI), delivery acknowledgment (e.g., Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). PRACH may transmit a random access preamble for establishing a connection with the cell.

[0330] In this disclosure, downlinks, uplinks, etc., may be expressed without the prefix "link." Also, the prefix "physical" may be omitted when describing various channels.

[0331] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc., may be transmitted. In the wireless communication system 1, as DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc., may be transmitted.

[0332] 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 SS (PSS, SSS) and PBCH (and DMRS for PBCH) may be called an SS / PBCH block, SS Block (SSB), etc. SS, SSB, etc., may also be called reference signals.

[0333] Furthermore, in the wireless communication system 1, the Uplink Reference Signal (UL-RS) may transmit the Sounding Reference Signal (SRS), Demodulation Reference Signal (DMRS), etc. The DMRS may also be called the User-Specific Reference Signal (UE-specific Reference Signal).

[0334] (base station) Figure 46 shows an example of the configuration of a base station according to one 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 one or more of the control unit 110, transceiver unit 120, transceiver antenna 130, and transmission line interface 140 may be provided.

[0335] In this example, the functional blocks of the characteristic parts of this 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 part described below may be omitted.

[0336] The control unit 110 controls the entire base station 10. The control unit 110 can consist of a controller, control circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0337] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may also control transmission and reception, measurement, etc., using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140. 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 also perform call processing of communication channels (setting, releasing, etc.), status management of the base station 10, management of radio resources, etc.

[0338] The transmitting / receiving 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 transmitting / receiving unit 120 can be composed of a transmitter / receiver, RF circuit, baseband circuit, filter, phase shifter, measurement circuit, transmitting / receiving circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0339] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or it may be composed of a transmitting unit and a receiving unit. The transmitting unit may consist of a transmitting processing unit 1211 and an RF unit 122. The receiving unit may consist of a receiving processing unit 1212, an RF unit 122 and a measuring unit 123.

[0340] The transmitting and receiving antenna 130 can be composed of an antenna described based on common understanding in the art relating to this disclosure, such as an array antenna.

[0341] The transmitting / receiving unit 120 may transmit the downlink channel, synchronization signal, downlink reference signal, etc. The transmitting / receiving unit 120 may also receive the uplink channel, uplink reference signal, etc.

[0342] The transmitting / receiving unit 120 may form at least one of the transmitting beam and the receiving beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0343] The transmitting / receiving unit 120 (transmission processing unit 1211) may perform processing on data and control information acquired from the control unit 110, for example, at the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer (e.g., RLC retransmission control), the Medium Access Control (MAC) layer (e.g., HARQ retransmission control), etc., to generate a bit sequence to be transmitted.

[0344] The transmitting / receiving unit 120 (transmission processing unit 1211) may perform transmission processing on the bit sequence to be transmitted, 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, and output a baseband signal.

[0345] The transmitting / receiving unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc., of the baseband signal to the radio frequency band and transmit the signal in the radio frequency band via the transmitting / receiving antenna 130.

[0346] 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 130.

[0347] The transmitting / receiving unit 120 (receiving processing unit 1212) may apply reception processing to the acquired baseband signal, such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing, to acquire user data, etc.

[0348] The transmitting / receiving unit 120 (measurement unit 123) may perform measurements related to 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 also measure received power (e.g., Reference Signal Received Power (RSRP)), reception 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.

[0349] The transmission path interface 140 may send and receive signals (backhaul signaling) with devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0350] In this disclosure, the transmitting and receiving units of the base station 10 may consist of at least one of a transmitting / receiving unit 120, a transmitting / receiving antenna 130, and a transmission path interface 140.

[0351] The transmitting / receiving unit 120 may transmit a first number of first synchronization signal blocks and a second number of second synchronization signal blocks. The control unit 110 may control initial access based on at least one of the first number of first synchronization signal blocks and the second number of second synchronization signal blocks.

[0352] The transmitting / receiving unit 120 may transmit a first synchronization signal block and a second synchronization signal block. The control unit 110 may control the reception of signals based on the second synchronization signal block based on the reception result of the first synchronization signal block.

[0353] The transmitting / receiving unit 120 may transmit a first synchronization signal block and a plurality of second synchronization signal blocks. The control unit 110 may control the transmission assuming that the plurality of second synchronization signal blocks are quasi-collated (QCL) with the first synchronization signal block.

[0354] The transmitting / receiving unit 120 may transmit a first synchronization signal block. If reception of the first synchronization signal block fails, the control unit 110 may control the reception of the preamble using a random access occasion for reporting the failure.

[0355] The transmitting / receiving unit 120 may receive messages in a random access procedure on a physical uplink shared channel. The control unit 110 may control at least one or more repetitions of transmitting a downlink channel that schedules the physical uplink shared channel and receiving the channel on the physical uplink shared channel.

[0356] The transmitting / receiving unit 120 may transmit a synchronization signal block including a first signal and a second signal. The control unit 110 may control the transmission of the synchronization signal block, assuming that the first beam used for the first signal is different from the second beam used for the second signal.

[0357] The transmitting / receiving unit 120 may transmit instructions for repetition for multiple types of signals. The control unit 110 may apply repetition to the multiple types of signals based on the instructions.

[0358] (User terminal) Figure 47 shows an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transmitting / receiving unit 220, and a transmitting / receiving antenna 230. Note that one or more of the control unit 210, the transmitting / receiving unit 220, and the transmitting / receiving antenna 230 may be provided.

[0359] In this example, the functional blocks of the characteristic parts of this embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

[0360] The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, control circuit, etc., as described based on common understanding in the technical field related to this disclosure.

[0361] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc., using the transmitting / receiving unit 220 and the transmitting / receiving antenna 230. The control unit 210 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transmitting / receiving unit 220.

[0362] The transmitting / receiving 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 transmitting / receiving unit 220 can be composed of a transmitter / receiver, RF circuit, baseband circuit, filter, phase shifter, measurement circuit, transmitting / receiving circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0363] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or it may be composed of a transmitting unit and a receiving unit. The transmitting unit may consist of a transmitting processing unit 2211 and an RF unit 222. The receiving unit may consist of a receiving processing unit 2212, an RF unit 222 and a measuring unit 223.

[0364] The transmitting and receiving antenna 230 can be composed of an antenna described based on common understanding in the art relating to this disclosure, such as an array antenna.

[0365] The transmitting / receiving unit 220 may receive the downlink channel, synchronization signal, downlink reference signal, etc. The transmitting / receiving unit 220 may also transmit the uplink channel, uplink reference signal, etc.

[0366] The transmitting / receiving unit 220 may use digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like to form at least one of the transmitting beam and the receiving beam.

[0367] The transmitting / receiving unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc., on data and control information acquired from the control unit 210, etc., to generate a bit sequence to be transmitted.

[0368] The transmitting / receiving unit 220 (transmission processing unit 2211) may perform transmission processing on the bit sequence to be transmitted, 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, and output a baseband signal.

[0369] Whether or not to apply DFT processing may be based on the transform precoding settings. The transmitting / receiving unit 220 (transmission processing unit 2211) may perform DFT processing as part of the transmission process to transmit a channel (for example, PUSCH) using a DFT-s-OFDM waveform if transform precoding is enabled for that channel, or it may not perform DFT processing as part of the transmission process if transform precoding is not enabled for that channel.

[0370] The transmitting / receiving unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc., of the baseband signal to the radio frequency band and transmit the signal in the radio frequency band via the transmitting / receiving antenna 230.

[0371] 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.

[0372] The transmitting / receiving unit 220 (receiving processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (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.

[0373] The transmitting / receiving unit 220 (measuring unit 223) may perform measurements related to the received signal. For example, the measuring unit 223 may perform RRM measurement, CSI measurement, etc., based on the received signal. The measuring unit 223 may also measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0374] In this disclosure, the transmitting and receiving units of the user terminal 20 may consist of at least one of a transmitting / receiving unit 220 and a transmitting / receiving antenna 230.

[0375] The transmitting / receiving unit 220 may receive at least one synchronization signal block, which includes a first number of first synchronization signal blocks and a second number of second synchronization signal blocks. The control unit 210 may control initial access based on the synchronization signal blocks.

[0376] The second number may be greater than the first number.

[0377] The transmission period of the second synchronization signal block may differ from the transmission period of the first synchronization signal block.

[0378] The second synchronization signal block may be transmitted aperiodically.

[0379] The transmitting / receiving unit 220 may attempt to receive the first synchronization signal block. The control unit 210 may control the reception of the second synchronization signal block based on the reception result of the first synchronization signal block.

[0380] When the first synchronization signal block is received, the control unit may control the transmission of the first preamble using the first random access channel occasion corresponding to the first synchronization signal block.

[0381] When the second synchronization signal block is received, the control unit may control the transmission of the second preamble using the second random access channel occasion corresponding to the second synchronization signal block.

[0382] If reception of the first synchronization signal block fails, the control unit may control the reception of the second synchronization signal block.

[0383] The transmitting / receiving unit 220 may receive at least one of the first synchronization signal block and the plurality of second synchronization signal blocks. The control unit 210 may control reception assuming that the plurality of second synchronization signal blocks are quasi-collated (QCL) with the first synchronization signal block.

[0384] If the first demodulation reference signal of the downlink is QCL'd with the first synchronization signal block, and the second demodulation reference signal of the downlink is QCL'd with one of the plurality of second synchronization signal blocks, the control unit may control reception assuming that the second demodulation reference signal is not QCL'd with the first demodulation reference signal.

[0385] If the first demodulation reference signal of the downlink is QCL'd with the first synchronization signal block, and the second demodulation reference signal of the downlink is QCL'd with one of the plurality of second synchronization signal blocks, the control unit may control reception assuming that the second demodulation reference signal is QCL'd with the first demodulation reference signal.

[0386] If a preamble is transmitted in a random access channel occasion corresponding to the synchronization signal block, the control unit may control reception assuming that the third demodulation reference signal of the downlink is QCLed with the synchronization signal block.

[0387] The transmitting / receiving unit 220 may attempt to receive the first synchronization signal block. If the reception of the first synchronization signal block fails, the control unit 210 may control the transmission of the preamble using a random access occasion for reporting the failure.

[0388] If reception of the first synchronization signal block fails, the receiving unit may attempt to receive the second synchronization signal block.

[0389] If reception of the first synchronization signal block fails, the receiving unit may attempt to receive the second synchronization signal block after transmitting the preamble.

[0390] If the reception of the first synchronization signal block fails and the reception of the second synchronization signal block succeeds, the control unit may control the transmission of the preamble.

[0391] The transmitting / receiving unit 220 may transmit messages in a random access procedure over a physical uplink shared channel. The control unit 210 may control at least one or more repetitions of receiving a downlink channel that schedules the physical uplink shared channel and transmitting over the physical uplink shared channel.

[0392] The control unit may use multiple beams for each of the multiple repetitions.

[0393] If the initial transmission of the message fails, the control unit may control the multiple repetitions of transmission on the physical uplink shared channel.

[0394] The random access procedure may be based on a first synchronization signal block, and the retransmission of the message may be based on a second synchronization signal block.

[0395] The transmitting / receiving unit 220 may receive a synchronization signal block including a first signal and a second signal. The control unit 210 may control the reception of the synchronization signal block, assuming that the first beam used for the first signal is different from the second beam used for the second signal.

[0396] The first signal corresponds to a first synchronization signal block index, the second signal corresponds to a second synchronization signal block index, and the first synchronization signal block index may be associated with a plurality of second synchronization signal block indices.

[0397] The first synchronization signal block index remains constant with each period, while the second synchronization signal block index may change with each period.

[0398] The first signal may be a synchronization signal, and the second signal may be a physical broadcast channel.

[0399] The transmitting / receiving unit 220 may receive instructions for repetition for multiple types of signals. The control unit 210 may apply repetition to the multiple types of signals based on the instructions.

[0400] If the application conditions are met, the control unit may apply repetition to the plurality of types of signals.

[0401] The instruction includes a plurality of repetition counts, and the control unit may apply one of the plurality of repetition counts to at least one of the plurality of types of signals.

[0402] The control unit may apply the beam corresponding to the second synchronization signal block to the iteration in the random access procedure based on the first synchronization signal block.

[0403] (Hardware configuration) The block diagrams used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may also be realized by combining the above one device or the above multiple devices with software.

[0404] Here, functions include, but are not limited to, judgment, decision, determination, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission may be called a transmitting unit or transmitter. In all cases, as mentioned above, the method of implementation is not particularly limited.

[0405] For example, a base station, user terminal, etc. in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 48 is a diagram showing an example of the hardware configuration of a base station and user terminal according to one embodiment. The base station 10 and user terminal 20 described above may be physically configured as a computer device including a processor 1001, memory 1002, storage 1003, communication device 1004, input device 1005, output device 1006, bus 1007, etc.

[0406] In this disclosure, terms such as apparatus, circuit, device, section, and unit are interchangeable. The hardware configuration of the base station 10 and the user terminal 20 may include one or more of the devices shown in the figure, or it may be configured to omit some of the devices.

[0407] For example, although only one processor 1001 is shown in the diagram, there may be multiple processors. Furthermore, processing may be performed by one processor, or by two or more processors simultaneously, sequentially, or by other means. Note that processor 1001 may be implemented using one or more chips.

[0408] 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 the processor 1001 and memory 1002, which allows the processor 1001 to perform calculations and control communication via the communication device 1004, or to control at least one of the reading and writing of data in the memory 1002 and storage 1003.

[0409] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may be composed of a central processing unit (CPU) that includes interfaces with peripheral devices, control units, arithmetic units, registers, etc. For example, at least a part of the control unit 110 (210) and the transmitting / receiving unit 120 (220) described above may be implemented by the processor 1001.

[0410] Furthermore, the processor 1001 reads programs (program code), 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 accordingly. The program used is one that causes the computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 110 (210) may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and other functional blocks may be implemented similarly.

[0411] Memory 1002 is a computer-readable recording medium and may consist of at least one of the following: Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. Memory 1002 may also be called a register, cache, or main memory. Memory 1002 can store executable programs (program code), software modules, etc., for carrying out a wireless communication method according to one embodiment of this disclosure.

[0412] Storage 1003 is a computer-readable recording medium and may consist of at least one of the following: a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (Compact Disc ROM (CD-ROM)), a digital multipurpose disk, a Blu-ray disk), 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 called an auxiliary storage device.

[0413] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may be configured to include, for example, a high-frequency switch, duplexer, filter, frequency synthesizer, etc., in order to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmitting / receiving unit 120 (220), transmitting / receiving antenna 130 (230), etc., may be implemented by the communication device 1004. The transmitting / receiving unit 120 (220) may be implemented with physically or logically separated implementations of a transmitting unit 120a (220a) and a receiving unit 120b (220b).

[0414] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, light-emitting diode (LED) lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0415] Furthermore, each device, such as the processor 1001 and memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or different buses may be configured for each device.

[0416] 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), and a field programmable gate array (FPGA), and some or all of each functional block may be implemented using such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0417] (modified version) In addition, terms used in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, channel, symbol, and signal (signal or signaling) may be used interchangeably. Also, a signal may be a message. A reference signal may be abbreviated as RS and may be called a pilot, pilot signal, etc., depending on the applicable standard. Also, a component carrier (CC) may be called a cell, frequency carrier, carrier frequency, etc.

[0418] A wireless frame may consist of one or more periods (frames) in the time domain. Each of these periods (frames) constituting a wireless frame may be called a subframe. Furthermore, a subframe may consist 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.

[0419] Here, the neuralelogy may be communication parameters applied to at least one of the transmission and reception of a signal or channel. The neuralelogy may be, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, or specific windowing processes performed by the transceiver in the time domain.

[0420] A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols or Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols). Alternatively, a slot may be a time unit based on neurology.

[0421] A slot may include multiple mini-slots. Each mini-slot may consist of one or more symbols in the time domain. Mini-slots may also be called sub-slots. Mini-slots may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot may be called a PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may be called a PDSCH (PUSCH) mapping type B.

[0422] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Wireless frames, subframes, slots, minislots, and symbols may each be referred to by different names. Furthermore, the units of time such as frames, subframes, slots, minislots, and symbols in this disclosure may be interpreted as interchangeable.

[0423] For example, one subframe may be called TTI, multiple consecutive subframes may be called TTI, or one slot or one mini-slot may be called TTI. In other words, at least one of the subframe and TTI may be a subframe (1ms) in existing LTE, a period shorter than 1ms (e.g., 1-13 symbols), or a period longer than 1ms. Note that the unit representing TTI may be called a slot, mini-slot, etc., instead of a subframe.

[0424] Here, TTI refers to, for example, the smallest unit of time for scheduling in wireless communication. For example, in an LTE system, the base station schedules each user terminal to allocate wireless resources (such as the frequency bandwidth and transmission power available to each user terminal) in TTI units. However, the definition of TTI is not limited to this.

[0425] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc. are mapped may be shorter than the given TTI.

[0426] Furthermore, if one slot or one mini-slot is referred to as TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit of scheduling. In addition, the number of slots (number of mini-slots) that constitute the minimum time unit of scheduling may be controlled.

[0427] A TTI with a time length of 1 ms may also be called a normal TTI (TTI in 3GPP Rel.8-12), a long TTI, a normal subframe, a long subframe, or a slot. A TTI shorter than a normal TTI may also be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a mini slot, a sub slot, or a slot.

[0428] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

[0429] A Resource Block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.

[0430] Furthermore, an RB may contain one or more symbols in the time domain and may have the length of one slot, one minislot, one subframe, or one TTI. Each TTI, subframe, etc., may consist of one or more resource blocks.

[0431] One or more RBs may also be called Physical RBs (PRBs), Sub-Carrier Groups (SCGs), Resource Element Groups (REGs), PRB pairs, RB pairs, etc.

[0432] Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.

[0433] A Bandwidth Part (BWP) (also called a partial bandwidth) may represent a subset of consecutive common resource blocks (RBs) for a given neurology in a given carrier. Here, the common RBs may be identified by an index of the RBs relative to the carrier's common reference point. PRBs may be defined and numbered within a BWP.

[0434] A BWP may include UL BWPs (BWPs for UL) and DL BWPs (BWPs for DL). One or more BWPs may be configured within a single carrier for a UE.

[0435] At least one of the configured BWPs may be active, and the UE does not need to assume that it will send or receive a given signal / channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be read as "BWP".

[0436] The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative examples. For instance, the number of subframes included in a wireless frame, the number of slots per subframe or wireless frame, the number of minislots within a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, and the number of symbols, symbol length, and cyclic prefix (CP) length within a TTI can be varied in various ways.

[0437] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or corresponding other information. For example, wireless resources may be indicated by a predetermined index.

[0438] The names used for parameters and other elements in this disclosure are not restrictive in any way. Furthermore, mathematical formulas and other elements that use these parameters may differ from those expressly disclosed in this disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0439] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0440] Furthermore, information, signals, etc., can be output from upper layers to lower layers and from lower layers to upper layers, or to at least one of the two. Information, signals, etc., may also be input and output via multiple network nodes.

[0441] Input and output information and signals may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information and signals may be overwritten, updated, or appended to. Output information and signals may be deleted. Input information and signals may be transmitted to other devices.

[0442] Information notification is not limited to the embodiments described herein and may be carried out by other means. For example, information notification in this disclosure may be carried out by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof).

[0443] Physical layer signaling may also be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signals), L1 control information (L1 control signals), etc. RRC signaling may also be called RRC messages, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc. MAC signaling may also be communicated using, for example, MAC Control Element (CE).

[0444] Furthermore, notification of the specified information (for example, notification that "X is the case") is not limited to explicit notification, but may also be made implicitly (for example, by not notifying the specified information or by notifying other information).

[0445] The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value represented as true or false, or by a numerical comparison (for example, a comparison with a predetermined value).

[0446] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0447] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or Digital Subscriber Line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0448] The terms “system” and “network” as used in this disclosure may be used interchangeably. “Network” may also mean the equipment included in the network (e.g., base stations).

[0449] In this disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "quasi-co-location (QCL)," "transmission configuration indication state (TCI state)," "spatial relation," "spatial domain filter," "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," and "panel" may be used interchangeably.

[0450] In this disclosure, terms such as "Base Station (BS)", "wireless 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", and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0451] A base station can house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of ​​the base station can be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms “cell” or “sector” refer to part or all of the coverage area of ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0452] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0453] A mobile station may also be called a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other appropriate term.

[0454] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0455] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this 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), Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, uplink channel and downlink channel may be interpreted as sidelink channel.

[0456] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station 10 may be configured to have the same functions as the user terminal 20 described above.

[0457] In this disclosure, operations performed by a base station may, in some cases, be performed by its upper node. In a network including one or more network nodes with base stations, it is clear that various operations performed for communication with terminals may be performed by the base station, one or more network nodes other than the base station (for example, a Mobility Management Entity (MME), a Serving Gateway (S-GW), etc., but not limited to these), or a combination thereof.

[0458] Each aspect / embodiment described in this disclosure may be used individually, in combination, or switched between during execution. Furthermore, the processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described in this disclosure may be rearranged in order, provided they are consistent. For example, the methods described in this disclosure present various step elements in an exemplary order and are not limited to that specific order.

[0459] Each aspect / embodiment described in this disclosure includes Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (where x is, for example, an integer or decimal)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM®), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi®), IEEE 802.16 (WiMAX®), and IEEE This may be applied to systems utilizing 802.20, Ultra-WideBand (UWB), Bluetooth®, or other appropriate wireless communication methods, as well as next-generation systems that extend these. It may also be applied in combination with multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0460] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

[0461] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, the references to the first and second elements do not imply that only two elements may be employed or that the first element must precede the second element in any way.

[0462] The term “determining” as used in this disclosure may encompass a wide variety of actions. For example, “determining” may be considered to include judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiry (e.g., searching in tables, databases, or other data structures), ascertaining, etc.

[0463] Furthermore, "judgment (decision)" may be considered as "judging (deciding)" things like receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory).

[0464] Furthermore, "judgment (decision)" can be considered as "judging (deciding)" something like resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment (decision)" can be considered as "judging (deciding)" something about an action.

[0465] Furthermore, "judgment (decision)" can be replaced with "assuming," "expecting," or "considering."

[0466] The term "maximum transmit power" as used in this disclosure may mean the maximum transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0467] As used in this disclosure, the terms “connected,” “coupled,” and any variations thereof mean any direct or indirect connection or coupling between two or more elements, and may include one or more intermediate elements between two elements that are “connected” or “coupled” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be replaced with “access.”

[0468] In this disclosure, when two elements are connected, they can be considered to be “connected” or “coupled” to each other using one or more wires, cables, printed electrical connections, etc., and, in some non-exclusive and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, or optical domain (both visible and invisible).

[0469] In this 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 "combine" may be interpreted similarly to "different."

[0470] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0471] In this disclosure, if articles are added by translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

[0472] Although the invention described herein has been explained in detail above, it will be clear to those skilled in the art that the invention described herein is not limited to the embodiments described herein. The invention described herein can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the claims. Therefore, the descriptions herein are for illustrative purposes only and do not imply any limitation on the invention described herein.

Claims

1. A receiving unit that attempts to receive the first synchronization signal block, The system includes a control unit that controls the reception of a second synchronization signal block based on the reception result of the first synchronization signal block, The control unit is a terminal that controls the transmission of the preamble using a random access occasion for reporting the failure if the reception of the first synchronization signal block fails.

2. The terminal according to claim 1, wherein the control unit controls the reception of the second synchronization signal block if the reception of the first synchronization signal block fails.

3. The step of attempting to receive the first synchronization signal block, A step of controlling the reception of a second synchronization signal block based on the reception result of the first synchronization signal block, A wireless communication method for a terminal, comprising the step of controlling the transmission of a preamble using a random access occasion for reporting the failure if the reception of the first synchronization signal block fails.

4. A transmitting unit that transmits a first synchronization signal block and a second synchronization signal block, The system includes a control unit that controls the reception of a signal based on a second synchronization signal block based on the reception result of the first synchronization signal block, The control unit controls the reception of the preamble using a random access occasion for reporting the failure when the terminal fails to receive the first synchronization signal block.

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