Signal transmission / reception method for wireless communication and apparatus therefor

Abstract

A terminal according to one embodiment may transmit a first message for performing a random access channel (RACH) procedure for a specific cell, receive a second message in response to the first message from the specific cell, and transmitting a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message on the basis of the specific minimum time interval.

Description

Technical Field

[0001] The present disclosure relates to wireless communication, and more particularly, to a method and apparatus for transmitting or receiving uplink / downlink signals in a wireless communication system. Background Art

[0002] Generally, wireless communication systems are evolving to cover different wide ranges to provide communication services such as audio communication services, data communication services, etc. Wireless communication is a multiple access system capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmission power, etc.). For example, the multiple access system may be any one of a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, and a single carrier frequency division multiple access (SC-FDMA) system. Summary of the Invention

[0003] Technical Problem

[0004] An object of the present disclosure is to provide a method for more accurately and efficiently transmitting and receiving signals.

[0005] The object of the present disclosure is not limited to what has been specifically described above, and other objects that the present disclosure can achieve will be more clearly understood from the following detailed description.

[0006] Technical Solution

[0007] According to one aspect, a method for a user equipment (UE) to transmit a signal in a wireless communication system may include: transmitting a first message for performing a random access channel (RACH) procedure for a specific cell; receiving a second message in response to the first message from the specific cell; and transmitting a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgment (HARQ-ACK) related to the second message based on a specific minimum time interval, where the specific minimum time interval is the sum of a physical downlink shared channel (PDSCH) processing time according to UE capabilities and a specific time, and where, based on the UE being a first UE whose bandwidth is limited to a first size, the specific time is configured as a second specific time longer than a first specific time for a second UE whose bandwidth is not limited to the first size.

[0008] The PUCCH may be transmitted based on a time interval between a last symbol of the PDSCH for the second message and a first symbol of the PUCCH being not less than the specific minimum time.

[0009] The second specific time may be configured as a time longer than the first specific time of 0.5 milliseconds.

[0010] The PDSCH may include a successful random access response (RAR) for the UE.

[0011] Based on the subcarrier spacing (SCS) size of the PDSCH related to the second message, the second specific time may be configured as 1 millisecond or 1.5 milliseconds.

[0012] Based on the SCS size of 15 KHz, the second specific time may be configured as 1.5 milliseconds.

[0013] Based on the SCS size of 30 KHz, the second specific time may be configured as 1 millisecond.

[0014] The second message may include a successful random access response (RAR), and based on the UE being the first UE, the transmission time slot of the PUCCH may be determined based on the value indicated by the HARQ feedback timing indicator field included in the successful RAR and the time slot offset configured separately for the first UE.

[0015] The time slot offset may be configured through System Information Block Type 1 (SIB1) or System Information (SI).

[0016] The first UE may be a first reduced-capability (RedCap) type UE capable of performing communication in a restricted bandwidth of 5 MHz, and the second UE may be a second RedCap type UE capable of performing communication in a restricted bandwidth of 20 MHz.

[0017] According to another aspect, a non-transitory computer-readable storage medium may be provided, which stores instructions for performing a signal reception method.

[0018] According to another aspect, a UE for performing a signal reception method may be provided.

[0019] According to another aspect, a processing device for controlling a UE performing a signal reception method may be provided.

[0020] According to another aspect, a method for a base station to receive signals in a wireless communication system includes: receiving a first message for performing a random access channel (RACH) procedure from a user equipment (UE); transmitting a second message in response to the first message; and receiving a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message based on a specific minimum time interval, where the specific minimum time interval is the sum of the physical downlink shared channel (PDSCH) processing time according to the UE capability and a specific time, and based on the UE being the first UE with a bandwidth restricted to a first size, the specific time is configured as a second specific time longer than a first specific time for a second UE with a bandwidth not restricted to the first size.

[0021] According to another aspect, a BS for performing a signaling method may be provided.

[0022] Advantageous Effects

[0023] According to an embodiment of the present disclosure, signal transmission and reception can be accurately and efficiently performed in a wireless communication system.

[0024] The present disclosure is not limited to the above-described technical effects, and other technical effects can be inferred from the detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Illustrate physical channels used in a Third Generation Partnership Project (3GPP) system, which is an exemplary wireless communication system, and a general signal transmission method using the physical channels.

[0026] Figure 2 Illustrate a radio frame structure.

[0027] Figure 3 Illustrate a resource grid of a time slot.

[0028] Figure 4 and Figure 5 is a schematic diagram for explaining the structure and transmission method of a Synchronization Signal Block (SSB).

[0029] Figure 6 Illustrate a random access procedure.

[0030] Figure 7 is a schematic diagram illustrating an exemplary two-step RACH procedure to which various embodiments of the present disclosure can be applied.

[0031] Figure 8 is a schematic diagram illustrating an exemplary contention-free RACH procedure to which various embodiments of the present disclosure can be applied.

[0032] Figure 9 Illustrate an exemplary mapping of physical channels in a time slot.

[0033] Figure 10 is a schematic diagram showing a flow of a method for transmitting and receiving signals according to an embodiment.

[0034] Figure 11 is a schematic diagram for explaining a method of configuring multiple sub-BWPs in one BWP.

[0035] Figure 12 is a schematic diagram for explaining a method by which a UE performs a RACH procedure to transmit a signal to a specific cell or BS.

[0036] Figure 13It is a schematic diagram for explaining a method by which a BS receives signals from a UE that executes a RACH procedure.

[0037] Figure 14 and Figure 15 Illustrates a communication system 1 and a wireless device to which the present disclosure is applied.

[0038] Figure 16 It is a schematic diagram for explaining discontinuous reception (DRX) operation of a UE according to one embodiment. Detailed implementation mode

[0039] Embodiments of the present disclosure are applicable to various radio access technologies such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single carrier frequency division multiple access (SC-FDMA). CDMA can be implemented as a radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA can be implemented as a radio technology such as global system for mobile communications (GSM) / general packet radio service (GPRS) / enhanced data rate GSM evolution (EDGE). OFDMA can be implemented as a radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and evolved UTRA (E-UTRA). UTRA is part of the universal mobile telecommunications system (UMTS). The 3rd Generation Partnership Project (3GPP) long term evolution (LTE) is part of the evolved UMTS (E-UMTS) that uses E-UTRA, and LTE-Advanced (A) is an evolved version of 3GPP LTE. 3GPP NR (new radio or new radio access technology) is an evolved version of 3GPP LTE / LTE-A.

[0040] As more and more communication devices require greater communication capacity, enhanced mobile broadband communication is needed relative to traditional radio access technologies (RATs). In addition, massive machine type communication (MTC) that can provide various services anytime and anywhere by connecting multiple devices and objects is another important issue to be considered in next-generation communication. The design of a communication system that takes into account services / UEs sensitive to reliability and latency is also being discussed. Therefore, the introduction of a new radio access technology that takes into account enhanced mobile broadband communication (eMBB), massive MTC, and ultra-reliable low-latency communication (URLLC) is being discussed. In the present disclosure, for simplicity, this technology will be referred to as NR (new radio or new RAT).

[0041] For clarity, 3GPP NR is mainly described, but the technical concept of the present disclosure is not limited thereto. LTE refers to the technology after 3GPP TS 36.xxx version 8. Specifically, the LTE technology after 3GPP TS 36.xxx version 10 is called LTE-A, and the LTE technology after 3GPP TS 36.xxx version 13 is called LTE-A pro. 3GPP NR refers to the technology after TS 38.xxx version 15. LTE / NR can be called the 3GPP system. In this document, "xxx" represents the detailed number of the specification. LTE / NR can be collectively referred to as the 3GPP system.

[0042] Details of the background, terms, abbreviations, etc. used in this document can be found in the documents published before the present disclosure. For example, the present disclosure can be supported by the following documents:

[0043] 3GPP NR

[0044] - 3GPP TS38.211: Physical Channels and Modulation

[0045] - 3GPP TS38.212: Multiplexing and Channel Coding

[0046] - 3GPP TS38.213: Physical Layer Procedures for Control

[0047] - 3GPP TS38.214: Physical Layer Procedures for Data

[0048] - 3GPP TS38.215: Physical Layer Measurements

[0049] - 3GPP TS38.300: NR and NG-RAN Overall Description

[0050] - 3GPP TS38.304: User Equipment (UE) Procedures in Idle Mode and RRC Inactive State

[0051] - 3GPP TS38.321: Media Access Control (MAC) Protocol

[0052] - 3GPP TS38.322: Radio Link Control (RLC) Protocol

[0053] - 3GPP TS38.323: Packet Data Convergence Protocol (PDCP)

[0054] - 3GPP TS38.331: Radio Resource Control (RRC) Protocol

[0055] - 3GPP TS37.324: Service Data Adaptation Protocol (SDAP)

[0056] - 3GPP TS37.340: Multi-Connection; General Description

[0057] - 3GPP TS23.287: Application Layer Support for V2X Services; Functional Architecture and Information Flows

[0058] - 3GPP TS23.501: System Architecture for 5G System

[0059] - 3GPP TS23.502: Procedures for 5G System

[0060] - 3GPP TS23.503: Policy and Charging Control Framework for 5G System; Stage 2

[0061] - 3GPP TS24.501: Non-Access Stratum (NAS) Protocol for 5G System (5GS); Stage 3

[0062] - 3GPP TS24.502: Access to 3GPP 5G Core Network (5GCN) via Non-3GPP Access Networks

[0063] - 3GPP TS24.526: User Equipment (UE) Policy for 5G System (5GS); Stage 3

[0064] Technical terms used in this document

[0065] - UE: User Equipment

[0066] - SSB: Synchronization Signal Block

[0067] - MIB: Master Information Block

[0068] - RMSI: Remaining Minimum System Information

[0069] - FR1: Frequency Range 1. Refers to the frequency range below 6 GHz (e.g., 450 MHz to 6000 MHz)

[0070] - FR2: Frequency Range 2. Refers to the millimeter wave (mmWave) region above 24 GHz (e.g., 24250 MHz to 52600 MHz)

[0071] - BW: Bandwidth

[0072] - BWP: Bandwidth Part

[0073] - RNTI: Radio Network Temporary Identifier

[0074] - CRC: Cyclic Redundancy Check

[0075] - SIB: System Information Block

[0076] -SIB1: SIB1 of the NR device = RMSI (Remaining Minimum System Information). Broadcasts the information necessary for the cell connection of the NR UE

[0077] -CORESET (Control Resource Set): The time / frequency resources where the NR UE attempts PDCCH candidates

[0078] -CORESET#0: The CORESET for C decoding of the Type0-PDCCH CSS set for the NR device (set in the MIB)

[0079] -Type0-PDCCH CSS set: A search space set where the NR UE monitors a group of PDCCH candidates with DCI formats having CRC scrambled by SI-RNTI

[0080] -MO: The PDCCH monitoring occasion for the Type0-PDCCH CSS set

[0081] -SIB1-R: The (additional) SIB1 for the NR device with reduced capabilities. Can be limited to generating it as a TB separate from SIB1 and transmitting it as a separate PDSCH

[0082] -CORESET#0-R: The CORESET#0 for the NR device with reduced capabilities

[0083] -Type0-PDCCH-R CSS set: A search space set where the redcap UE monitors a group of PDCCH candidates with DCI formats having CRC scrambled by SI-RNTI

[0084] -MO-R: The PDCCH monitoring occasion for the Type0-PDCCH CSS set

[0085] -Cell Definition SSB (CD-SSB): An SSB that includes the RMSI scheduling information between NR SSBs

[0086] -Non-Cell Definition SSB (Non-CD-SSB): An SSB placed in the NR synchronization grid but does not include the RMSI scheduling information of the cell for measurement. However, it can contain information indicating the location of the Cell Definition SSB

[0087] -SCS: Subcarrier Spacing

[0088] -SI-RNTI: System Information Radio Network Temporary Identifier

[0089] -Resident On: "Resident On" is a UE state where the UE stays on the cell and is ready to initiate potential dedicated services or receive ongoing broadcast services

[0090] -TB: Transport Block

[0091] -RSA (Redcap Standalone): Units that only support Redcap devices or services

[0092] -SIB1(-R)-PDSCH: PDSCH that sends SIB1(-R)

[0093] -SIB1(-R)-DCI: DCI used to schedule SIB1(-R)-PDSCH. DCI format with CRC scrambled by SI-RNTI

[0094] -SIB1(-R)-PDCCH: PDCCH that sends SIB1(-R)-DCI

[0095] -FDRA: Frequency Domain Resource Allocation

[0096] -TDRA: Time Domain Resource Allocation

[0097] -RA: Random Access

[0098] -MSGA: Preamble and payload transmission for 2-step RA type random access procedure

[0099] -MSGB: Response to MSGA in the 2-step random access procedure. MSGB may include a response for contention resolution, a backoff indication, and a backoff indication.

[0100] -RO (RACH timing) for RO-N: 4-step RACH and 2-step RACH for normal UEs (if configured)

[0101] -RO-N1, RO-N2: If a separate RO is set for the 2-step RACH of normal UE, the RO is divided into RO-N1 (4 steps), RO-N2 (2 steps)

[0102] -RO-R: RO (RACH timing) for 4-step RACH and 2-step RACH (if configured) for redcap UEs, set separately from RO-N

[0103] -RO-R1, RO-R2: If a separate RO is set for 2-step RACH of redcap UE, the RO is divided into RO-R1 (4 steps) and RO-R2 (2 steps)

[0104] -PG-R: MsgA preamble group for redcap UE

[0105] -RAR: Random Access Response

[0106] -RAR window: time window for monitoring RA response

[0107] - FH: Frequency Hopping

[0108] - iBWP: Initial BWP

[0109] - iBWP - DL(-UL): Initial DL(UL) BWP

[0110] - iBWP - DL(-UL)-R: (Separate) Initial DL(UL) BWP for RedCap

[0111] - CS: Cyclic Shift

[0112] - NB: Narrow Band

[0113] In the present disclosure, the terms "set / setting" may be replaced with "configure / configuration", and the two may be used interchangeably. In addition, conditional expressions (e.g., "if", "in this case", or "when...") may be replaced with "based on" or "in the case / state of...". In addition, operations or software / hardware (SW / HW) configurations of a user equipment (UE) / base station (BS) may be derived / understood based on the satisfaction of corresponding conditions. When the process on the receiving (or transmitting) side can be derived / understood from the process on the transmitting (or receiving) side in signal transmission / reception between wireless communication devices (e.g., BS and UE), its description may be omitted. For example, signal determination / generation / encoding / transmission on the transmitting side may be understood as signal monitoring reception / decoding / determination on the receiving side. In addition, when it is said that the UE performs (or does not perform) a specific operation, this may also be interpreted as the BS expecting / assuming (or not expecting / assuming) the UE to perform the specific operation. When it is said that the BS performs (or does not perform) a specific operation, this may also be interpreted as the UE expecting / assuming (or not expecting / assuming) the BS to perform the specific operation. In the following description, for ease of description, sections, embodiments, examples, options, methods, schemes, proposals, etc. are distinguished from each other and labeled with indices, which does not mean that each of them necessarily constitutes an independent disclosure or that each of them can only be implemented separately. Unless explicitly contradictory to each other, it can be derived / understood that at least some of the sections, embodiments, examples, options, methods, schemes, proposals, etc. can be implemented in combination or can be omitted.

[0114] In a wireless communication system, a user equipment (UE) receives information from a base station (BS) via a downlink (DL) and transmits information to the BS via an uplink (UL). The information transmitted and received by the BS and the UE includes data and various control information, and various physical channels are included according to the type / use of the information transmitted and received by the UE and the BS.

[0115] Figure 1 Illustrate the physical channels used in the 3GPP NR system and the general signal transmission method using the same.

[0116] When the UE powers on again from the powered-off state or enters a new cell, in step S101, the UE performs an initial cell search process (e.g., establish synchronization with the BS). For this purpose, the UE receives a Synchronization Signal Block (SSB) from the BS. The SSB includes a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). The UE establishes synchronization with the BS based on the PSS / SSS and obtains information such as the cell identifier (ID). The UE can obtain broadcast information in the cell based on the PBCH. The UE can receive a DL Reference Signal (RS) during the initial cell search process to monitor the DL channel state.

[0117] The SSB consists of four consecutive OFDM symbols, each symbol carrying PSS, PBCH, SSS / PBCH, or PBCH. Each of the PSS and SSS includes one OFDM symbol multiplied by 127 subcarriers, and the PBCH includes three OFDM symbols multiplied by 576 subcarriers. The PBCH is encoded / decoded based on a polar code and modulated / demodulated according to Quadrature Phase Shift Keying (QPSK). The PBCH in the OFDM symbol consists of data resource elements (REs) to which the complex modulation values of the PBCH are mapped and Demodulation Reference Signals (DMRS) REs to which the DMRS for the PBCH are mapped. Three DMRS REs are configured for each RB in the OFDM symbol, and three data REs are configured between the DMRS REs.

[0118] The PSS can be used in detecting the cell ID within a cell ID group, and the SSS can be used in detecting the cell ID group. The PBCH can be used in detecting the SSB (time) index and the half-frame. There are 336 cell ID groups, and each cell ID group includes three cell IDs. Therefore, there are a total of 1008 cell IDs.

[0119] The SSB is transmitted periodically with an SSB period. The default SSB period assumed by the UE during the initial cell search is defined as 20 ms. After cell access, the SSB period can be set by the network (e.g., the BS) to one of {5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms}. An SSB burst set can be configured at the start of the SSB period. The SSB burst set can be set to a time window of 5 ms (i.e., a half-frame), and the SSB can be repeatedly transmitted up to L times within the SS burst set. The maximum number L of SSB transmissions can be given depending on the carrier frequency band as follows. One time slot includes up to two SSBs.

[0120] - For a frequency range up to 3 GHz, L = 4

[0121] - For a frequency range from 3 GHz to 6 GHz, L = 8

[0122] - For a frequency range from 6 GHz to 52.6 GHz, L = 64

[0123] The time domain position of candidate SSBs in an SS burst set can be defined depending on the subcarrier spacing. The time domain position of candidate SSBs is indexed in chronological order from (SSB index) 0 to L - 1 within the SSB burst set (i.e., half - frame).

[0124] Multiple SSBs can be transmitted within the frequency span of a carrier. Each SSB may not need to have a unique physical layer cell identifier, but different SSBs may have different physical layer cell identifiers.

[0125] The UE can obtain DL synchronization by detecting SSBs. The UE can identify the structure of the SSB burst set based on the detected SSB (time) index, and thus the UE can detect symbol / slot / half - frame boundaries. The frame / half - frame number to which the detected SSB belongs can be identified based on the system frame number (SFN) information and the half - frame indication information.

[0126] Specifically, the UE can obtain the 10 - bit SFN of the frame to which the PBCH belongs from the PBCH. Then, the UE can obtain 1 - bit half - frame indication information. For example, when the UE detects a PBCH in which the half - frame indication bit is set to 0, the UE can determine that the SSB to which the PBCH belongs is included in the first half - frame of the frame. When the UE detects a PBCH in which the half - frame indication bit is set to 1, the UE can determine that the SSB to which the PBCH belongs is included in the second half - frame of the frame. Finally, the UE can obtain the SSB index of the SSB to which the PBCH belongs based on the PBCH payload carried by the PBCH and the DMRS sequence.

[0127] After initial cell search, in step S102, the UE can obtain more specific system information by receiving the physical downlink control channel (PDCCH) and receiving the physical downlink shared channel (PDSCH) based on the information of the PDCCH.

[0128] System information (SI) is divided into a master information block (MIB) and multiple system information blocks (SIBs). SI other than the MIB can be referred to as remaining minimum system information (RMSI). Details will be described below.

[0129] - The MIB includes information / parameters of the PDCCH for monitoring the PDSCH carrying SIB1 (System Information Block1), and the MIB is sent by the BS on the PBCH of the SSB. For example, the UE can check, based on the MIB, whether there is a CORESET for the Type0-PDCCH common search space. The Type0-PDCCH common search space is a type of PDCCH search space used to send the PDCCH for scheduling SI messages. If there is a Type0-PDCCH common search space, the UE can determine, based on the information in the MIB (e.g., pdcch-ConfigSIB1), (i) the multiple consecutive RBs and one or more consecutive symbols included in the CORESET, and (ii) the PDCCH occasion (e.g., the time-domain position for PDCCH reception). If the Type0-PDCCH common search space does not exist, pdcch-ConfigSIB1 provides information about the frequency position where the SSB / SIB1 exists and information about the frequency range where the SSB / SIB1 does not exist.

[0130] - SIB1 includes information related to the availability and scheduling (e.g., transmission periodicity, SI window size, etc.) of the remaining SIBs (hereinafter referred to as SIBx, where x is an integer greater than or equal to 2). For example, SIB1 can indicate whether SIBx is broadcast periodically or provided on demand in response to a UE request. When SIBx is provided on demand, SIB1 can include the information necessary for the UE to send an SI request. SIB1 is sent on the PDSCH, and the PDCCH scheduling SIB1 is sent in the Type0-PDCCH common search space. That is, SIB1 is sent on the PDSCH indicated by the PDCCH.

[0131] - SIBx is included in the SI message and sent on the PDSCH. Each SI message is sent within a time window (i.e., SI window) that appears periodically.

[0132] In steps S103 to S106, the UE can perform a random access procedure (e.g., 4-step RA procedure) to access the BS. For random access, the UE can send a preamble to the BS on the physical random access channel (PRACH) (S103), and receive a response message for the preamble on the PDCCH and the PDSCH corresponding to the PDCCH (S104). In the case of contention-based random access, the UE can perform a contention resolution procedure by further sending the PRACH (S105) and receiving the PDCCH and the PDSCH corresponding to the PDCCH (S106).

[0133] In the following, the two-step random access procedure will be briefly described. In the two-step random access procedure, S103 / S105 (where the UE performs transmission) (Message A) can be carried out in one step, and S104 / S106 (where the BS performs transmission) (Message B) can be carried out in one step. Message A (MsgA) can include a preamble and a payload (PUSCH payload), and the preamble and the payload can be multiplexed based on time division multiplexing (TDM). In response to MsgA, Message B (MsgB) can be sent for contention resolution, (one or more) fallback indication, and / or backoff indication. The two-step random access procedure can be subdivided into a contention-based random access (CBRA) procedure and a contention-free random access (CFRA) procedure. In the CFRA procedure, the BS can provide the UE with information about the preamble that the UE needs to send in MsgA and information about PUSCH allocation before the UE sends MsgA.

[0134] After the foregoing procedure, the UE can receive PDCCH / PDSCH (S107) and send a physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) (S108), as a general downlink / uplink signal transmission procedure. The control information sent from the UE to the BS is referred to as uplink control information (UCI). UCI includes hybrid automatic repeat request and acknowledgement / negative acknowledgement (HARQ-ACK / NACK), scheduling request (SR), channel state information (CSI), etc. CSI includes a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), etc. Although UCI is usually sent on the PUCCH, when it is necessary to send control information and traffic data simultaneously, UCI can be sent on the PUSCH. Additionally, UCI can be sent non-periodically via the PUSCH according to the request / command of the network.

[0135] The MR system can support signal transmission / reception in the unlicensed band. According to the regional regulations for the unlicensed band, communication nodes in the unlicensed band need to determine whether the channel is being used by other communication node(s) before transmitting a signal. Specifically, a communication node can perform carrier sensing (CS) before transmitting a signal to check whether other communication node(s) are performing signal transmission. When it is determined that other communication node(s) are not performing signal transmission, it can be said that the clear channel assessment (CCA) is confirmed. When the CCA threshold is predefined or configured by higher layer signaling (e.g., RRC signaling), if the detected channel energy is higher than the CCA threshold, the communication node can determine that the channel is busy. Otherwise, the communication node can determine that the channel is idle. When it is determined that the channel is idle, the communication node can start signal transmission in the UCell. The above series of processes can be referred to as listen before talk (LBT) or channel access procedure (CAP). LBT and CAP can be used interchangeably in this document.

[0136] Figure 2 Illustrative radio frame structure. In NR, uplink transmission and downlink transmission are configured with frames. Each radio frame has a length of 10 ms and is divided into two 5 ms half-frames (HF). Each half-frame is divided into five 1 ms sub-frames (SF). A sub-frame is divided into one or more time slots, and the number of time slots in a sub-frame depends on the subcarrier spacing (SCS). According to the cyclic prefix (CP), each time slot includes 12 or 14 orthogonal frequency division multiplexing (OFDM) symbols. When using normal CP, each time slot includes 14 OFDM symbols. When using extended CP, each time slot includes 12 OFDM symbols.

[0137] Table 1 exemplarily shows that the number of symbols per time slot, the number of time slots per frame, and the number of time slots per sub-frame vary according to the SCS when using normal CP.

[0138] [Table 1]

[0139] SCS(15*2^u) <![CDATA[N slot symb > <![CDATA[N frame,u slot > <![CDATA[N subframe,u slot > 15KHz (u = 0) 14 10 1 30KHz (u = 1) 14 20 2 60KHz (u = 2) 14 40 4 120KHz (u = 3) 14 80 8 240KHz (u = 4) 14 160 16

[0140] *N slot symb : Number of symbols in a time slot

[0141] *N frame,u slot : Number of time slots in a frame

[0142] *N subframe,u slot : Number of time slots in a sub-frame

[0143] Table 2 shows that the number of symbols per time slot, the number of time slots per frame, and the number of time slots per sub-frame vary according to the SCS when using extended CP.

[0144] [Table 2]

[0145] SCS(15*2^u) <![CDATA[N slot symb > <![CDATA[N frame,u slot > <![CDATA[N subframe,u slot > 60KHz (u = 2) 12 40 4

[0146] The structure of the frame is merely an example. The number of sub-frames, time slots, and symbols in the frame can vary.

[0147] In the NR system, OFDM parameter sets (e.g., SCS) can be configured differently for multiple cells aggregated for one UE. Therefore, the (absolute time) duration of a time resource (e.g., SF, time slot, or TTI) composed of the same number of symbols (referred to as time unit (TU) for simplicity) can be configured differently among the aggregated cells. Here, the symbols can include OFDM symbols (or CP-OFDM symbols) and SC-FDMA symbols (or discrete Fourier transform - spread - OFDM (DFT - s - OFDM) symbols).

[0148] Figure 3 A resource grid showing a time slot is presented. A time slot includes multiple symbols in the time domain. For example, when using normal CP, a time slot includes 14 symbols. However, when using extended CP, a time slot includes 12 symbols. A carrier includes multiple sub - carriers in the frequency domain. A resource block (RB) is defined as multiple consecutive sub - carriers in the frequency domain (e.g., 12 consecutive sub - carriers). A bandwidth part (BWP) can be defined as multiple consecutive physical RBs (PRBs) in the frequency domain and corresponds to a single parameter set (e.g., SCS, CP length, etc.). A carrier can include up to N (e.g., five) BWPs. Data communication can be performed through the enabled BWP, and only one BWP can be enabled for one UE. In the resource grid, each element is called a resource element (RE), and one complex symbol can be mapped to each RE.

[0149] Figure 4 and Figure 5 is a schematic diagram for explaining the structure and transmission method of an SSB (synchronization signal block).

[0150] A UE can perform cell search, system information acquisition, beam alignment for initial access, DL measurement, etc. based on the SSB. The term SSB and synchronization signal / physical broadcast channel (SS / PBCH) block will be used interchangeably.

[0151] Refer to Figure 4, the SSB includes the PSS, SSS, and PBCH. The SSB includes four consecutive OFDM symbols carrying the PSS, PBCH, SSS / PBCH, and PBCH respectively. Each of the PSS and SSS includes one OFDM symbol with 127 subcarriers, and the PBCH includes three OFDM symbols with 576 subcarriers. Polar coding and quadrature phase shift keying (QPSK) are applied to the PBCH. The PBCH includes data REs and DMRS REs in each OFDM symbol. Each RB has three DMRS REs, with three data REs between every two adjacent DMRS REs.

[0152] Cell search is the process of obtaining time / frequency synchronization with a cell and detecting the cell ID (e.g., physical layer cell ID (PCID)) of the cell at the UE. The PSS is used to detect the cell ID in a cell ID group, and the SSS is used to detect the cell ID group. The PBCH is used to detect the SSB (time) index and half-frame.

[0153] The cell search process of the UE can be summarized in Table 3 below.

[0154] [Table 3]

[0155]

[0156] There can be 336 cell ID groups, with each group including three cell IDs. In total, there can be 1008 cell IDs. Information about the cell ID group to which a cell ID belongs can be provided / obtained through the SSS of the cell, and information about the cell ID among the 336 cells of the cell ID can be provided / obtained through the PSS.

[0157] Refer to Figure 5 , the SSB is transmitted periodically according to the SSB period. The default SSB period assumed by the UE during initial cell search is defined as 20 ms. After cell access, the SSB period can be set to one of {5 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms} by the network (e.g., BS). The SSB burst set is configured at the start of the SSB period. The SSB burst set can include a 5 ms time window (i.e., half-frame), and the SSB can be transmitted up to L times within the SSB burst set. According to the frequency band of the carrier, the maximum allowed transmission times L of the SSB can be given as follows. One time slot includes up to two SSBs.

[0158] - For a frequency range up to 3 GHz, L = 4

[0159] - For a frequency range from 3 GHz to 6 GHz, L = 8

[0160] - For the frequency range from 6 GHz to 52.6 GHz, L = 64

[0161] The time positions of SSB candidates in an SS burst set can be defined according to the SCS as follows. In an SSB burst set (i.e., a half-frame), indices (SSB indices) from 0 to L-1 are assigned in chronological order to the time positions of SSB candidates.

[0162] - Case A - 15-kHz SCS: The index of the first symbol of a candidate SSB is given as {2,8} + 14×n, where for carrier frequencies equal to or below 3 GHz, n = 0, 1, and for carrier frequencies from 3 GHz to 6 GHz, n = 0, 1, 2, 3.

[0163] - Case B - 30-kHz SCS: The index of the first symbol of a candidate SSB is given as {4,8,16,20} + 28×n, where for carrier frequencies equal to or below 3 GHz, n = 0, and for carrier frequencies from 3 GHz to 6 GHz, n = 0, 1.

[0164] - Case C - 30-kHz SCS: The index of the first symbol of a candidate SSB is given as {2,8} + 14×n, where for carrier frequencies equal to or below 3 GHz, n = 0, 1, and for carrier frequencies from 3 GHz to 6 GHz, n = 0, 1, 2, 3.

[0165] - Case D - 120-kHz SCS: The index of the first symbol of a candidate SSB is given as {4,8,16,20} + 28×n, where for carrier frequencies above 6 GHz, n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18.

[0166] - Case E - 240-kHz SCS: For carrier frequencies above 6 GHz, the index of the first symbol of a candidate SSB is given as {8,12,16,20,32,36,40,44} + 56×n, where n = 0, 1, 2, 3, 5, 6, 7, 8.

[0167] Bandwidth Part (BWP)

[0168] In the NR system, up to 400 MHz per carrier can be supported. When the UE operating in this wideband carrier always operates with the radio frequency (RF) module of the entire carrier turned on, the battery consumption of the UE may increase. Alternatively, considering various use cases (e.g., eMBB, URLLC, mMTC, etc.) operating within a single wideband carrier, different parameter sets (e.g., SCS) can be supported for each frequency band within the carrier. Alternatively, each UE can have a different maximum bandwidth capability. In this regard, the BS can indicate to the UE to operate only in a partial bandwidth rather than in the total bandwidth of the wideband carrier. The partial bandwidth can be defined as the BWP. The BWP is a subset of consecutive common RBs defined for the parameter set μi in the BWP i on the carrier, and a parameter set (e.g., SCS, CP length, or slot or mini-slot duration) can be configured for the BWP.

[0169] The BS can configure one or more BWPs in one carrier configured for the UE. Alternatively, when the UE is concentrated on a specific BWP, the BS can configure another BWP for some of the UEs for load balancing. Alternatively, the BS can exclude a certain spectrum of the entire bandwidth and configure the BWPs on both sides of the cell in the same time slot considering the frequency-domain inter-cell interference cancellation between neighboring cells. That is, the BS can configure at least one DL / UL BWP for the UEs associated with the wideband carrier, activate at least one of the DL / UL BWPs configured at a specific time point (through L1 signaling as a physical layer control signal, MAC control element (CE) as a MAC layer control signal, or RRC signaling), or set a timer value and switch the UE to a predetermined DL / UL BWP after the timer expires. To indicate the switch to another configured DL / UL BWP, DCI format 1_1 or DCI format 0_1 can be used. The activated DL / UL BWP can be referred to as the active DL / UL BWP. During initial access or before RRC connection establishment, the UE cannot receive the configuration of the DL / UL BWP from the BS. The DL / UL BWP assumed by the UE in this case is defined as the initial active DL / UL BWP.

[0170] Figure 6 An exemplary normal random access procedure is illustrated. Specifically, Figure 6 A contention-based random access procedure of the UE is shown, which is performed in four steps.

[0171] First, the UE can send a message 1 (Msg1) including a random access preamble on the PRACH (see Figure 6 1701 of (a)).

[0172] It is possible to support random access preamble sequences with different lengths. The long sequence length of 839 can be applied to SCSs of 1.25 and 5 kHz, and the short sequence length of 139 can be applied to SCSs of 15, 30, 60, and 120 kHz.

[0173] Multiple preamble formats can be defined by one or more RACH OFDM symbols and different CPs (and / or guard times). The RACH configuration for a cell can be included in the SI regarding the cell and provided to the UE. The RACH configuration can include information such as the SCS of the PRACH, available preambles, preamble formats, etc. The RACH configuration can include information about the association between the SSB and the RACH (time-frequency) resources. The UE sends a random access preamble on the RACH time-frequency resources associated with the detected or selected SSB.

[0174] The threshold of the SSB for RACH resource association can be configured by the network, and the RACH preamble can be sent or retransmitted based on the SSB, where the reference signal received power (RSRP) measured based on the SSB meets the threshold. For example, the UE can select an SSB from among the SSBs that meet the threshold and send or retransmit the RACH preamble based on the RACH resources associated with the selected SSB.

[0175] Upon receiving a random access preamble from the UE, the BS can send message 2 (Msg2) corresponding to the random access response (RAR) message (see Figure 6 (a) of 1703 in

[0176] The RAR information transmitted on the PDSCH may include timing advance (TA) information for UL synchronization, an initial UL grant, and a temporary cell-RNTI (C-RNTI). The TA information may be used to control the UL signal transmission timing. The UE may transmit a UL signal on the UL shared channel as Message 3 (Msg3) of the random access procedure based on the RAR information (see Figure 6 1705 of (a) in Figure 6 ). Msg3 may include an RRC connection request and a UE identifier. In response to Msg3, the network may transmit Message 4 (Msg4), which may be regarded as a contention resolution message on the DL (see 1707 of (a) in

[0177] ). When receiving Msg4, the UE may enter the RRC_CONNECTED state.

[0178] On the other hand, when the UE is switched to another cell or BS or when it is requested by the BS, a contention-free random access procedure may be performed. In the contention-free random access procedure, a preamble to be used by the UE (hereinafter referred to as a dedicated random access preamble) is allocated by the BS. Information about the dedicated random access preamble may be included in an RRC message (e.g., a handover command) or provided to the UE through a PDCCH command. When initiating the random access procedure, the UE may send the dedicated random access preamble to the BS. When the UE receives an RAR from the BS, the random access procedure is completed.

[0179] [Table 4]

[0180] RAR UL Grant Field Number of bits Frequency Hopping Flag 1 Msg3 PUCCH Frequency Resource Allocation 12 Msg3 PUSCH Time Resource Allocation 4 Modulation and Coding Scheme (MCS) 4 Transmit Power Control (TPC) for Msg3 PUSCH 3 CSI Request 1

[0181] In the contention-free random access (CFRA) procedure, the CSI request field in the RAR UL grant indicates whether the terminal includes an aperiodic CSI report in the corresponding PUSCH transmission. The subcarrier spacing for Msg3 PUSCH transmission may be provided by an RRC parameter. The terminal may send a PRACH and Msg3PUSCH on the same uplink carrier in the same serving cell. The UL BWP for Msg3 PUSCH transmission is indicated by System Information Block 1 (SIB1).

[0182] Figure 7

[0183] A (contention-based) RACH procedure that is executed in two steps, i.e., the two-step RACH procedure, is proposed to simplify the RACH procedure, thus achieving low signaling overhead and low latency.

[0184] In the two-step RACH procedure, the operations of sending Msg 1 and sending Msg 3 in the four-step RACH procedure can be combined into the operation of the UE sending a message (Message A (Msg A) including PRACH and PUSCH). The operation of the BS sending Msg 2 and the operation of the BS sending Msg 4 in the four-step RACH procedure can be combined into the operation of sending a message (Message B (Msg B) including RAR and contention resolution information).

[0185] That is to say, in the two-step RACH procedure, the UE can combine Msg 1 and Msg 3 of the four-step RACH procedure into a message (e.g., Msg A) and send the message to the BS (1301).

[0186] In addition, in the two-step RACH procedure, the BS can combine Msg 2 and Msg 4 of the four-step RACH procedure into a message (e.g., Msg B) and send the message to the UE (1303).

[0187] Based on the combination of these messages, the two-step RACH procedure can become a RACH procedure with low latency.

[0188] More specifically, in the two-step RACH procedure, Msg A can include the PRACH preamble included in Msg 1 and the data included in Msg 3. In the two-step RACH procedure, Msg B can include the RAR included in Msg 2 and the contention resolution information included in Msg 4.

[0189] Contention-Free RACH Procedure

[0190] Figure 8 It is a schematic diagram illustrating an exemplary contention-free RACH procedure applicable to various embodiments of the present disclosure.

[0191] The contention - free RACH procedure can be used for handover of a UE to another cell or BS, or can be performed when requested by a BS command. The contention - free RACH procedure is basically similar to the contention - based RACH procedure. However, compared with the contention - based RACH procedure where a preamble to be used is randomly selected from multiple RACH preambles, in the contention - free RACH procedure, the BS assigns the preamble to be used by the UE (referred to as a dedicated RACH preamble) to the UE (801). Information about the dedicated RACH preamble can be included in an RRC message (e.g., handover command) or provided to the UE via a PDCCH command. When the RACH procedure starts, the UE sends the dedicated RACH preamble to the BS (803). When the UE receives the RAR from the BS, the RACH procedure is completed (805).

[0192] In the contention - free RACH procedure, the CSI request field in the RAR UL grant indicates whether the UE includes an aperiodic CSI report in the corresponding PUSCH transmission. The SCS for Msg3 PUSCH transmission is provided by an RRC parameter. The UE can send the PRACH and Msg3 PUSCH on the same UL carrier of the same serving cell. The UL BWP for Msg3 PUSCH transmission is indicated by SIB1.

[0193] Figure 9 Exemplary mapping of physical channels in an illustrative time slot.

[0194] Refer to Figure 9 , the PDCCH can be sent in the DL control region, and the PDSCH can be sent in the DL data region. The PUCCH can be sent in the UL control region, and the PUSCH can be sent in the UL data region. The guard period (GP) provides a time gap for the transmission mode to reception mode switch or reception mode to transmission mode switch at the BS and the UE. Some symbols at the DL - to - UL handover in a subframe can be configured as the GP.

[0195] Each physical channel will be described in more detail below.

[0196] The PDCCH delivers DCI. For example, the PDCCH (i.e., DCI) can carry information about the transmission format and resource allocation of the DL shared channel (DL-SCH), resource allocation information for the uplink shared channel (UL-SCH), paging information about the paging channel (PCH), system information about the DL-SCH, information about the resource allocation of higher layer control messages (such as the RAR sent on the PDSCH), transmit power control commands, information about the activation / release of configured scheduling, etc. The DCI includes a cyclic redundancy check (CRC). The CRC is masked with various identifiers (IDs) (e.g., radio network temporary identifier (RNTI)) according to the owner or use of the PDCCH. For example, if the PDCCH is for a specific UE, the CRC is masked with the UE ID (e.g., cell RNTI (C-RNTI)). If the PDCCH is for a paging message, the CRC is masked with the paging RNTI (P-RNTI). If the PDCCH is for system information (e.g., system information block (SIB)), the CRC is masked with the system information RNTI (SI-RNTI). When the PDCCH is for the RAR, the CRC is masked with the random access RNTI (RA-RNTI).

[0197] The PDCCH includes 1, 2, 4, 8, or 16 control channel elements (CCEs) according to its aggregation level (AL). A CCE is a logical allocation unit for providing a specific code rate for the PDCCH according to the radio channel state. A CCE includes 6 resource element groups (REGs), each REG being defined by one OFDM symbol multiplied by one (P)RB. The PDCCH is transmitted in a control resource set (CORESET). The CORESET is defined as a set of REGs with a given parameter set (e.g., SCS, CP length, etc.). Multiple CORESETs for one UE can overlap with each other in the time domain / frequency domain. The CORESET can be configured by system information (e.g., master information block (MIB)) or UE-specific higher layer signaling (e.g., radio resource control (RRC) signaling). Specifically, the number of RBs and the number of symbols (up to 3) in the CORESET can be configured by higher layer signaling.

[0198] For PDCCH reception / detection, the UE monitors PDCCH candidates. A PDCCH candidate is a CCE that the UE should monitor to detect a PDCCH. According to the AL, each PDCCH candidate is defined as 1, 2, 4, 8, or 16 CCEs. Monitoring includes (blind) decoding of PDCCH candidates. The set of PDCCH candidates decoded by the UE is defined as the PDCCH search space (SS). The SS can be a common search space (CSS) or a UE-specific search space (USS). The UE can obtain DCI by monitoring PDCCH candidates in one or more SSs configured by the MIB or higher-layer signaling. Each CORESET is associated with one or more SSs, and each SS is associated with a CORESET. The SS can be defined based on the following parameters.

[0199] - controlResourceSetId: The CORESET associated with the SS.

[0200] - monitoringSlotPeriodicityAndOffset: The PDCCH monitoring periodicity (in terms of slots) and the PDCCH monitoring offset (in terms of slots).

[0201] - monitoringSymbolsWithinSlot: The PDCCH monitoring symbols within a slot (e.g., the first symbol of the CORESET).

[0202] - nrofCandidates: The number of PDCCH candidates for each AL = {1, 2, 4, 8, 16} (one of 0, 1, 2, 3, 4, 5, 6, and 8).

[0203] * Where the occasion (e.g., time / frequency resource) when the UE is going to monitor PDCCH candidates is defined as the PDCCH (monitoring) occasion. One or more PDCCH (monitoring) occasions can be configured within a slot.

[0204] Table 5 shows the characteristics of each SS.

[0205] [Table 5]

[0206]

[0207] Table 6 shows the DCI formats transmitted on the PDCCH.

[0208] [Table 6]

[0209]

[0210] DCI format 0_0 can be used to schedule TB (or TB-level) based PUSCH, and DCI format 0_1 can be used to schedule TB (or TB-level) based PUSCH or codeblock group (CBG) (or CBG-level) based PUSCH. DCI format 1_0 can be used to schedule TB (or TB-level) based PDSCH, and DCI format 1_1 can be used to schedule TB (or TB-level) based PDSCH or CBG (or CBG-level) based PDSCH (DL grant DCI). DCI formats 0_0 / 0_1 can be referred to as UL grant DCI or UL scheduling information, and DCI formats 1_0 / 1_1 can be referred to as DL grant DCI or DL scheduling information. DCI format 2_0 is used to deliver dynamic slot format information (e.g., dynamic slot format indicator (SFI)) to the UE, and DCI format 2_1 is used to deliver DL preemption information to the UE. DCI format 2_0 and / or DCI format 2_1 can be delivered on the group common PDCCH to a corresponding group of UEs, which is the PDCCH for a group of UEs.

[0211] DCI formats 0_0 and 1_0 can be referred to as fallback DCI formats, while DCI formats 0_1 and 1_1 can be referred to as non-fallback DCI formats. In the fallback DCI formats, the DCI size / field configuration remains the same regardless of the UE configuration. In contrast, the DCI size / field configuration varies depending on the UE configuration in the non-fallback DCI formats.

[0212] The PDSCH carries DL data (e.g., DL shared channel transport block (DL-SCH TB)) and uses modulation schemes such as quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (16QAM), 64QAM, or 256QAM. The TB is encoded into codewords. The PDSCH can carry up to two codewords. Scrambling and modulation mapping can be performed on a codeword basis, and the modulation symbols generated from each codeword can be mapped to one or more layers. Each layer is mapped to resources together with the demodulation reference signal (DMRS), and the OFDM symbol signal is generated from the mapped layer with DMRS and transmitted through the corresponding antenna port.

[0213] The PUCCH carries uplink control information (UCI). The UCI includes the following information.

[0214] - SR (scheduling request): Information used to request UL-SCH resources.

[0215] - HARQ (Hybrid Automatic Repeat reQuest) - ACK (ACKnowledgment): Response to DL data packets (e.g., codewords) on the PDSCH. The HARQ-ACK indicates whether the DL data packet has been successfully received. In response to a single codeword, 1-bit HARQ-ACK can be sent. In response to two codewords, 2-bit HARQ-ACK can be sent. The HARQ-ACK response includes positive ACK (simply referred to as ACK), negative ACK (NACK), Discontinuous Transmission (DTX), or NACK / DTX. The term HARQ-ACK is interchangeable with HARQ ACK / NACK and ACK / NACK.

[0216] - CSI (Channel State Information): Feedback information for DL channels. The feedback information related to Multiple-Input Multiple-Output (MIMO) includes RI and PMI.

[0217] The PUSCH delivers UL data (e.g., UL Shared Channel Transport Block (UL-SCH TB)) and / or UCI based on the CP-OFDM waveform or the DFT-s-OFDM waveform. When the PUSCH is sent in the DFT-s-OFDM waveform, the UE sends the PUSCH through transform precoding. For example, when transform precoding is not possible (e.g., disabled), the UE can send the PUSCH in the CP-OFDM waveform, and when transform precoding is possible (e.g., enabled), the UE can send the PUSCH in the CP-OFDM waveform or the DFT-s-OFDM waveform. The PUSCH transmission can be dynamically scheduled by UL grant in DCI, or semi-statically scheduled (configured scheduling or configured grant) by higher layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling such as PDCCH). The PUSCH transmission can be performed in a codebook-based or non-codebook-based manner.

[0218] In NR, one or more SPS PDSCHs can be configured for the UE for periodic transmission and reception or for low latency and PDCCH overhead. Each SPS configuration can have a period and can repeat the configured / indicated resources. That is, the initially configured / indicated resource allocation can repeat at the configured period, and the UE can perform downlink reception on the corresponding resources without a separate PDCCH reception process. The types of data to be generated in XR are diverse. Among these data, information about the UE's sensors and location and video data that is usually reported at a specific period are sent and received from the SPS resources. These data may not always have a constant traffic arrival time and may experience jitter due to reasons such as video encoding time, sensor measurement time, upper layer operations, or routing changes in the network that transmits the data.

[0219] When allocating resources to a position that is far enough in time from the expected service occurrence time considering jitter and the like, resource availability can be ensured, but delays may occur. On the contrary, when allocating SPS resources with a fixed period at the expected data generation time, when jitter occurs, a greater delay may occur due to the time of waiting until the next available resource.

[0220] Some data is generated based on events, so the actual data generation time cannot be accurately determined. However, SPS resources can be considered for this data to reduce the delay time caused by scheduling. In this case, a skipping method has been discussed in the past, in which sufficient resources are allocated in a short period to prepare for data generation, and the UE or BS selectively uses these resources, while actually not using other resources. However, in order to use the skipping method for transmission and reception, careful consideration of the response signal between the UE and the BS is required to determine whether to receive and send data. When the UE sends a response signal even for an unreceived transmission, the BS needs to always prepare resources for the UE to send the response signal. Considering that the skipping method is based on configuring sufficient resources for these resources within the radio resources, this may become a large uplink burden. Considering that these resources may be multiplexed among UEs, more attention needs to be paid to considering the burden of UL resources.

[0221] Ensuring low latency is required for the quality of service of XR. Therefore, it is necessary to consider a method of minimizing the latency impact while reducing the impact of jitter. To solve this problem, the present disclosure relates to a method of selectively using some of the multiple SPS resources configured between the UE and the BS and sending a response to the SPS resources so used to a predetermined position in a simplified manner.

[0222] Although the proposed method is described based on the semi-static configuration of DL SPS radio resources, those skilled in the art can understand that the method can be extended and applied to radio resources allocated by dynamic scheduling received by the UE. For example, a method of determining a single HARQ-ACK timing for multiple DL radio resources allocated to the UE can be applied, regardless of the SPS PDSCH and the PDSCH indicated by dynamic scheduling. Obviously, as long as the principle of the present disclosure is not violated, the method can be applied to all types of transmission and reception methods expected by the BS and the UE. For ease of description, in the following disclosure, SPS is used as a general concept and collectively referred to as radio resources set semi-statically (e.g., DL / UL SPS, CG).

[0223] Hereinafter, the transmission occasion (TO) means the radio resources configured for SPS purposes (e.g., SPS PDSCH). The entity that performs transmission at the TO (i.e., the BS for DL or the UE for UL) may attempt to transmit at the TO, and the receiver (i.e., the UE for DL or the BS for UL) may expect transmission at each TO and attempt to receive.

[0224] Hereinafter, examples are given based on the NR system to explain the principles of the present disclosure. However, unless otherwise specified, the proposed method does not specifically limit the transmission and reception forms of NR. Hereinafter, examples are given based on the characteristics and structures of XR services to explain the principles of the present disclosure. However, the following method does not specifically limit the support for XR services, unless otherwise specified. Therefore, it is obvious that as long as the principles of the present disclosure are not violated, the present disclosure can be applied to all wireless communication transmission and reception structures and services even without separate explanation.

[0225] Narrower DL BWP for System Information and Paging

[0226] Recently, in addition to the 5G main use cases (mMTC, eMBB, and URLLC), the importance / interest in the use case areas across mMTC and eMBB or across mMTC and URLLC has increased. These use cases may include connected industries, smart cities, wearable devices, etc. To more efficiently support the above use cases in terms of terminal cost / complexity, power consumption, etc. in a wireless communication system, new types of terminals different from traditional NR terminals have been introduced. Such new types of terminals may be referred to as NR terminals with reduced capabilities (hereinafter referred to as RedCap UE / terminals or RedCap). And to distinguish the new type of terminals from conventional NR terminals, conventional NR terminals may be referred to as non-RedCap UE / terminals or non-RedCap. RedCap terminals are cheaper and have lower power consumption than non-RedCap terminals, and specifically, may have all or some of the following functions.

[0227] A. Functions related to complexity reduction:

[0228] - Reduced maximum UE bandwidth

[0229] - Reduced number of UE RX / TX branches / antennas

[0230] - Half-duplex FDD

[0231] - Relaxed UE processing time

[0232] - Relaxed UE processing capability

[0233] B. Functions related to power saving:

[0234] - Extended DRX for RRC Inactive and / or Idle

[0235] - Relaxed RRM for Fixed Devices

[0236] The target use cases of Redcap terminals with the above functions may include the following items:

[0237] 1) Connected Industry

[0238] - Sensors and actuators connected to the 5G network and core

[0239] - Large-scale Industrial Wireless Sensor Networks (IWSN)

[0240] - Relatively low-cost services with a small device form factor and a battery life of several years, in addition to URLLC services with very high requirements

[0241] - Requirements for these services are higher than those of Low Power Wide Area (LPWA, i.e., LTE-M / NB-IOT) but lower than those of URLCC and eMBB

[0242] - Pressure sensors, humidity sensors, thermometers, motion sensors, accelerometers, actuators, etc.

[0243] 2) Smart City

[0244] - Data collection and processing to more efficiently monitor and control urban resources and provide services

[0245] - Basic surveillance cameras for factories, industries, and smart cities

[0246] 3) Wearable Devices

[0247] - Smartwatches, rings, electronic health-related devices, medical monitoring devices, etc.

[0248] - Small devices, etc.

[0249] Compared with non-RedCap terminals, RedCap UEs may have lower transmission and reception performance. The main reason is the reduction in frequency diversity performance due to the reduction of the terminal bandwidth. As the supported terminal bandwidth decreases, the degree of performance reduction increases.

[0250] Considering the main use cases of RedCap, such as wearable devices and large-scale wireless sensors, service congestion is expected because large-scale connections need to be supported through narrow bandwidths.

[0251] A method for solving the above problems is proposed, namely, supporting terminal frequency hopping (hereinafter referred to as FH) and supporting service offloading (hereinafter referred to as TO).

[0252] In this specification, "()" can be interpreted as excluding the content within () and including the content within the brackets. In this specification, " / " can mean including all the content separated by / (and) or only including some of the content separated by / (or).

[0253] Multiple RedCap UE Types and BWP Modes

[0254] In this specification, the following multiple different RedCap UE types are supported. In particular, at least two types are supported.

[0255] (1) Rel.17 RedCap UE (hereinafter referred to as Rel.17 R-UE): Rel.17 R-UE supports a 20 MHz BWP

[0256] (2) Rel.18 RedCap UE (hereinafter referred to as Rel.18 R-UE): The Rel.18 R-UE terminal supports a 5 MHz BWP (or a 5 MHz sub-BWP or a 5 MHz BW position)

[0257] 1) Option BW1: For UL / DL, both the RF and baseband (BB) bandwidths of the terminal support 5 MHz.

[0258] 2) Option BW2: For all UL / DL signals / channels, the terminal supports a 5 MHz BB bandwidth and a 20 MHz RF bandwidth.

[0259] 3) Option BW3: For PDSCH (unicast / broadcast PDSCH) and PUSCH, only a 5 MHz BB bandwidth is supported, and for UL / DL, a 20 MHz RF bandwidth is supported. However, for different physical channels and signals, an RF+BB bandwidth of up to 20 MHz of the UE is supported.

[0260] In this specification, Rel.18 PDSCH or DCI can refer to the PDSCH or DCI for Rel.18 R-UE. Rel.17 PDSCH, legacy PDSCH, or PDSCH before Rel.18 can refer to the PDSCH for non-RedCap UE regardless of Rel.17 R-UE or version, and Rel.17 DCI, legacy DCI, or DCI before Rel.18 can refer to the DCI for non-RedCap UE regardless of Rel.17 R-UE or version.

[0261] In this specification, the BWP for Rel.18 R-UE can be replaced by a sub-BWP or a BW position and can have a size of 5 MHz or less.

[0262] Figure 10Shows the flow of a signal transmission and reception method according to an embodiment.

[0263] Referring to Figure 10 , the UE may receive system information (1005). The UE may configure an initial BWP (1010). The UE may receive a paging signal from the BS (1015) and perform a RACH procedure for initial access from the BS (1020).

[0264] Specifically, the UE generally configures / activates an initial BWP in the RRC_IDLE or RRC_INACTIVE state and performs an initial access procedure / process through the initial BWP in the active state. For R18 RedCap UEs, the BS may allocate the PDSCH by dividing the initial BWP for normal UEs and / or the R17 initial BWP for R17 RedCap UEs into N 5MHz BWPs. For example, when an R18 RedCap UE can only receive PDSCH transmissions up to 5MHz, the 20MHz initial BWP may be divided into N 5MHz sub-BWPs, and the Rel-18 PDSCH may be transmitted through one or more specific 5MHz sub-BWPs of the 20MHz initial BWP for system information transmission and / or paging transmission.

[0265] The R18 RedCap UE may be explicitly configured with multiple 5MHz sub-BWPs separated within the 20MHz initial BWP or the initial BWP for normal UEs, or may be allocated frequency resources corresponding to the 5MHz sub-BWPs (hereinafter referred to as bandwidth) within the 20MHz initial BWP or the initial BWP for normal UEs without an explicit configuration for separating multiple 5MHz sub-BWPs. Hereinafter, for ease of explanation, it is assumed that the R18 RedCap UE is configured with multiple 5MHz sub-BWPs separated within a specific BWP, but the present disclosure is not limited thereto, and it can also be applied to cases where the 5MHz sub-BWP or 5MHz frequency bandwidth is indicated by a resource allocation method without an explicit separation configuration.

[0266] Method for Configuring One or More Sub-BWPs

[0267] Figure 11 Is a schematic diagram for explaining a method of configuring multiple sub-BWPs in one BWP.

[0268] Referring to Figure 11, a UE in the RRC_CONNECTED state can configure up to four UE-specific BWPs (or sub-BWPs) for a BWP. In this case, the UE can activate only one of the four sub-BWPs. For example, the BS can configure up to N sub-BWPs for a specific BWP k of the UE. (N = 1, 2, 3, 4...). In this case, the sub-BWPs can be configured to be non-overlapping with each other (non-overlapping sub-BWPs) as shown in Figure 9 or can be configured to be fully / partially overlapping.

[0269] For example, when a BWP is an 8 MHz BWP, the sub-BWPs can be configured as a 5 MHz sub-BWP and a 3 MHz sub-BWP to be non-overlapping with each other within 8 MHz. Alternatively, the sub-BWPs can be configured as 4 MHz sub-BWPs that are non-overlapping with each other within the 8 MHz BWP, or as 5 MHz sub-BWPs that partially overlap with each other. In this case, each sub-BWP can be configured by the following methods.

[0270] (1) Method 1: The BS can indicate the starting PRB and the number of PRBs (consecutive PRBs) of each sub-BWP. The starting PRB of the sub-BWP can be indicated / configured via the relative offset from the starting PRB of the specific BWP connected to the sub-BWP.

[0271] (2) Method 2: The BS can configure the sub-BWPs according to the value of N by indicating the number N of sub-BWPs of a specific BWP. When the M PRBs constituting the specific BWP are divided into N sub-BWPs, each sub-BWP can be configured to include PRBs equal to the value of Ceiling(M / N) or Floor(M / N).

[0272] - For example, each sub-BWP can include PRBs corresponding to the number of PRBs calculated based on Ceiling(M / N). For example, when M = 5 and N = 2, Ceiling(M / N) = 3, and thus each sub-BWP includes three PRBs, and among the five PRBs of the specific BWP, the lower three PRBs (i.e., the three PRBs with relatively low PRB indices) are assigned to the first sub-BWP, and the higher three PRBs (i.e., the three PRBs with relatively high PRB indices) are assigned to the second sub-BWP. In this case, the third PRB of the specific BWP can be configured as the frequency resource where the two sub-BWPs overlap with each other.

[0273] - Each sub - BWP may include PRBs corresponding to the number of PRBs calculated based on Floor(M / N). For example, when M = 5 and N = 2, Floor(M / N)=2, and thus each sub - BWP includes two PRBs. Among the five PRBs of a specific BWP, the lower two PRBs (i.e., the two PRBs with relatively low PRB indices) are allocated to the first sub - BWP, and the higher two PRBs (i.e., the two PRBs with relatively high PRB indices) are allocated to the second sub - BWP. In this case, the third PRB of the specific BWP may be configured as a guard frequency resource (or guard band) that does not belong to any sub - BWP.

[0274] For example, when two or more sub - BWPs are configured for a specific BWP, a specific sub - BWP among the two or more sub - BWPs may be determined / indicated as the first active sub - BWP (or default sub - BWP, initial sub - BWP, default BW position, or associated sub - BWP) via an RRC message (or MAC CE or DCI). Here, the specific BWP and the specific sub - BWP may be the specific BWP and / or specific sub - BWP for DL and / or UL. Thus, when the first active sub - BWP is configured for a specific BWP of a specific cell, the UE may activate / configure the first active sub - BWP of the specific BWP or switch to the first active sub - BWP of the specific BWP. Then, the UE may transmit PUSCH in the first active sub - BWP indicated / configured for the specific UL BWP and receive PDCCH and / or PDSCH in the first active sub - BWP indicated / configured for the specific DL BWP.

[0275] PDSCH Processing / HARQ Feedback Time Relaxation Method during Initial Access

[0276] An RRC_IDLE or RRC_INACTIVE UE may transition to the RRC_CONNECTED mode through the initial access procedure. Alternatively, when performing an RRC re - establishment procedure such as RLF, the UE may perform the initial connection procedure. Alternatively, the UE may perform the initial access procedure to the target cell through a mobility procedure such as handover. When performing an RACH procedure to perform such an initial access procedure, the UE may first select the initial DL / UL BWP, then perform PRACH preamble and / or MSG3 / MSGAPUSCH transmission, and receive MSG2 / MSGB and / or MSG4 PDCCH / PDSCH. In this case, an R18 R - UE may be configured to a separate initial (DL / UL) BWP different from existing UEs, and when no separate initial BWP is configured, the initial BWP configured for an R17 R - UE may be selected. Alternatively, when no initial BWP is configured for an R17 / 18 R - UE, the R18 R - UE may select the initial BWP configured for a normal UE.

[0277] When the R18 R-UE receives the PDSCH during the RACH procedure, the R18 R-UE may have a longer PDSCH processing time than other normal UEs (e.g., UEs without bandwidth restrictions or R17 R-UEs). Therefore, it is necessary to ensure a longer PUCCH transmission time slot for transmitting the HARQ-ACK for the PDSCH. Alternatively, it is necessary to ensure a longer interval between the reception time slot of the PDSCH and the transmission time slot of the PUCCH for transmitting the HARQ-ACK for the PDSCH. Considering this, an adjustment (Alleviation) of the PDSCH processing and / or HARQ feedback time during the RACH procedure of the R18 R-UE may be required.

[0278] First, the content related to the RACH procedure performance of normal UEs or R17 R-UEs is described. A normal UE or R17 R-UE can perform a 4-step RACH as shown in Table 7 below. For example, a normal UE or R17 R-UE can transmit a PRACH based on the 4-step RACH defined in Table 7 and perform HARQ-ACK transmission for PDSCH reception. In this case, a normal UE or R17 R-UE can expect the time interval between the last symbol of the PDSCH of MSG4 and the first symbol of the PUCCH to be not less than the minimum time interval (NT, 1 + 0.5 milliseconds).

[0279] [Table 7]

[0280]

[0281] Alternatively, a normal UE or R17 R-UE can perform a 2-step RACH. For example, a normal UE or R17 R-UE can perform PUCCH transmission including HARQ-ACK for MSGB PDSCH reception based on the HARQ feedback timing indicator field and the minimum time interval (defined in Table 8). In this case, a normal UE or R17 R-UE can expect the time interval between the last symbol of the MSGB PDSCH and the first symbol of the PUCCH to be not less than the minimum time interval (N T,1 + 0.5 milliseconds).

[0282] [Table 8]

[0283]

[0284] Based on the method for a normal UE or R17 R-UE to perform the RACH procedure, the method for configuring and adjusting the PDSCH processing and / or HARQ feedback time for the R18 R-UE is described below.

[0285] When the R18 R-UE requires relaxed PDSCH processing and / or HARQ feedback time, the R18 R-UE may report such relaxed requirements to the BS via RACHMSG1 or MSGA. The reporting method for this requirement may not apply to R17 R-UEs and only applies to R18 R-UEs.

[0286] (1) When PDSCH processing time relaxation is required for receiving MSG2 PDSCH after receiving MSG2 PDCCH in a 4-step RACH

[0287] When PDSCH processing time is required to receive MSG2 PDSCH after receiving MSG2 PDCCH in a 4-step RACH, the R18 R-UE may receive MSG2 PDSCH by applying a more relaxed PDSCH processing time (compared to normal UEs or R17 R-UEs).

[0288] -> Option 1A: A separate N1 processing capability value may be applied for the R18 R-UE.

[0289] -> Option 1B: The PDSCH processing time for the R18 R-UE may be extended by 0.75 milliseconds or an additional time N T,1 + 0.75 milliseconds.

[0290] For example, considering the above options, the R18 R-UE may perform the reception of MSG2 PDSCH after receiving MSG2 PDCCH as shown in Table 9 below (see TS 38.214).

[0291] [Table 9]

[0292]

[0293] (2) When PUCCH transmission for reporting HARQ-ACK for PDSCH needs to be relaxed during the RACH procedure

[0294] Alternatively, for PUCCH transmissions reporting HARQ-ACKs received for MSG4 PDSCH in the 4-step RACH or for PUCCH transmissions reporting HARQ-ACKs received for MSGB PDSCH in the 2-step RACH, relaxation may be required. These R18 R-UEs may apply a more relaxed HARQ feedback timing (compared to normal UEs or R17 R-UEs) to transmit HARQ-ACKs for MSG4 PDSCH or MSGB PDSCH. In other words, during the initial access procedure when the UE capabilities are unknown, the UE may not know which sub-BWP to select, so the R18 R-UE may receive MSGB or MSG4 over a bandwidth exceeding 5 MHz (e.g., 20 MHz). In such a case, due to its limited processing capabilities for PDSCH, etc., the R18 R-UE may not be able to transmit HARQ-ACKs for MSGB PDSCH (or MSG4 PDSCH) within the minimum time interval required by a normal UE (i.e., without bandwidth limitations). Therefore, as described below, relaxation may be required for PUCCH transmissions used to report HARQ-ACKs received for MSGB PDSCH (or MSG4 PDSCH).

[0295] That is, the minimum time interval between the last symbol of MSG4 PDSCH reception (or MSGB PDSCH) and the start symbol (the first symbol) of the PUCCH transmission reporting the HARQ-ACK can be relaxed for R18 R-UEs. The detailed relaxation method can be based on at least one of the following options.

[0296] -> Option 2A: A separate N1 processing capability value can be applied for R18 R-UEs.

[0297] -> Option 2B: A specific additional time can be added to the "N T,1 + 0.5 ms" formula for determining the existing minimum time interval for R18 R-UEs, or the 0.5 ms can be extended / prolonged to a longer time.

[0298] - For example, if the 0.5 ms is extended / prolonged to a longer time of 1.5 ms, the minimum time interval for the R18 R-UE can be determined to be the time corresponding to / equal to N T,1 + 1.5 ms, or if a specific additional time of 1 ms is added for the R18 R-UE, the minimum time interval for the R18 R-UE can be determined to be the time corresponding to N T,1 + 0.5 ms + 1 ms.

[0299] - In this case, when the interval between the last symbol of PDSCH reception (receiving PDSCH via MSG4 / MSGB) and the first symbol of the PUCCH including HARQ-ACK information is not less than the minimum time interval of R18 R-UE, the R18 R-UE can send the PUCCH.

[0300] - Alternatively, the R18 R-UE can have different minimum time intervals according to the (subcarrier spacing) size of the PDSCH. For example, when the SCS size is 15 KHz, the minimum time interval can be determined / configured as N T,1 + 1.5 milliseconds, and when the SCS size is 30 KHz, the minimum time interval can be determined / configured as N T,1 + 1 millisecond.

[0301] -> Option 2C (for 2-step RACH): A specific offset value for individual R18 RedCap can be applied to the R18 R-UE. For example, n + k + Δ + 2 μ ·K redcap_offset 。

[0302] For example, based on the above options (especially Option 2B), the R18 R-UE can send the PUCCH reporting HARQ-ACK for MSG4 PDSCH reception according to the minimum time interval in Table 10 below.

[0303] [Table 10]

[0304]

[0305] That is to say, according to Table 10, the minimum time between the last symbol of PDSCH reception and the first symbol of the corresponding PUCCH transmission including HARQ-ACK information can correspond / to be equal to N T,1 + 0.5 milliseconds + additional specific time of the R18 R-UE. Here, (when additional PDSCH DM-RS is configured) N T,1 can be the duration of N1 symbols corresponding to the PDSCH processing time of UE processing capability 1 or R18 R-UE specific processing capability.

[0306] As described above, based on the above options, the R18 R-UE can send the PUCCH reporting HARQ-ACK for MSGB PDSCH reception. That is to say, even in the 2-step RACH process, the R18 R-UE can send the PUCCH reporting HARQ-ACK for MSGB PDSCH reception based on the minimum time interval determined by the above Options 2A to 2C.

[0307] Alternatively, referring to Table 11 below, based on the PUCCH transmission time slot with period Tslot, the PUCCH transmission time slot can be indicated by the 3-bit HARQ feedback timing indicator field included in the successful RAR. Here, the bit value of the HARQ feedback timing indicator field can be mapped to any one of the k values {1, 2, 3, 4, 5, 6, 7, 8} (for μ ≤ 3), any one of the k values {7, 8, 12, 16, 20, 24, 28, 32} (μ = 5), or any one of the k values {13, 16, 24, 32, 40, 48, 56, 64} (μ = 6). For example, the PUCCH transmission time slot can be determined as n + k + Δ + 2μ·Kcell,offset + 2μ·K_redcap_offset. K_redcap_offset applied to R18 R-UE can be indicated / configured in the gNB via SIB1 or other SI or UE-specific signaling. If no separate configuration is specified, K_redcap_offset can be 0.

[0308] [Table 11]

[0309]

[0310] The time interval between the last symbol of the PDSCH reception expected by the R18 R-UE and the first symbol of the PUCCH is not less than the minimum time interval of the R18 R-UE (N T,1 + 0.5 ms + specific additional time, or N T,1 + 1.5 ms or N T,1 + 1.0 ms) (see Option 2B).

[0311] (3) Relaxation of PUCCH transmission for reporting HARQ-ACK for PDSCH reception (related to HARQ timing)

[0312] Alternatively, for PUCCH transmission reporting HARQ-ACK for MSG4 PDSCH reception in 4-step RACH or for PUCCH transmission reporting HARQ-ACK for MSGB PDSCH reception in 2-step RACH, relaxation may be required. These R18 R-UEs can apply more relaxed HARQ feedback timing (compared to normal UEs or R17 R-UEs) to send HARQ-ACK for MSG4 PDSCH or MSGB PDSCH.

[0313] In other words, during the initial access procedure when the UE capabilities are unknown, the UE may not know which sub-BWP to select, and thus an R18 R-UE may receive an MSGB or MSG4 with a bandwidth exceeding 5 MHz (e.g., 20 MHz). In this case, the R18 R-UE may not be able to send HARQ-ACK for the PDSCH included in the MSGB within the minimum time interval required for a normal UE (i.e., without bandwidth restrictions) due to its limited processing capabilities for PDSCH, etc. Therefore, as described below, it may be necessary to relax the PUCCH transmission for reporting HARQ-ACK for the reception of the MSGB PDSCH.

[0314] Specifically, for DCI format 1_0 that schedules a PDSCH transmitted via MSG4 (e.g., RRC Setup and / or Contention Resolution MAC CE) or MSGB (e.g., SuccessRAR MAC CE), the PUCCH for transmitting HARQ-ACK information for the PDSCH can be sent in a time slot determined based on the value of the PDSCH-to-HARQ feedback timing indicator field in the DCI, as described below.

[0315] - When the UE is not an R18 R-UE (i.e., a normal UE or an R17 R-UE), the UE can determine the time slot for PUCCH transmission based on the value of the 3-bit PDSCH-to-HARQ feedback timing indicator field mapped to {1, 2, 3, 4, 5, 6, 7, 8}. For example, when the PDSCH-to-HARQ feedback timing indicator field value is 000, the UE can send the PUCCH including HARQ-ACK in the first time slot after the PDSCH reception time slot, when the PDSCH-to-HARQ feedback timing indicator field value is 001, the UE can send the PUCCH including HARQ-ACK in the second time slot after the PDSCH reception time slot, and when the PDSCH-to-HARQ feedback timing indicator field value is 010, the UE can send the PUCCH including HARQ-ACK in the third time slot after the PDSCH reception time slot.

[0316] When the UE is an R18 R-UE, the UE can re-interpret the 3-bit PDSCH-to-HARQ feedback timing indicator field value and map it to a different (extended) set of time slots (e.g., {7, 8, 12, 16, 20, 24, 28, 32}) from the 3-bit PDSCH-to-HARQ feedback timing indicator field value. For example, when the PDSCH-to-HARQ feedback timing indicator field value is 000, the UE can transmit the PUCCH including HARQ-ACK in the seventh time slot after the PDSCH reception time slot, when the PDSCH-to-HARQ feedback timing indicator field value is 001, the UE can transmit the PUCCH including HARQ-ACK in the eighth time slot after the PDSCH reception time slot, and when the PDSCH-to-HARQ feedback timing indicator field value is 010, the UE can transmit the PUCCH including HARQ-ACK in the twelfth time slot after the PDSCH reception time slot.

[0317] For example, for the HARQ-ACK of the MSG4 PDSCH or the MSGB PDSCH for the RACH, the R18 R-UE can report to the gNB information about using / mapping a different (and extended) set of time slots for the PDSCH-to-HARQ feedback timing indicator field value via a specific PRACH preamble ID (alternatively, in a specific RACH case, a specific LCID value of the MAC PDU of the MSG3 or MSGA PUSCH).

[0318] During the initial access procedure when the UE capability is unknown, the UE may not know the sub-BWP to be selected and thus can receive the PDSCH during the RACH procedure according to the relaxed method described above. However, after switching to the RRC_CONNECTED mode, the BS can know the UE's capability and thus the BS can configure a separate sub-BWP for the UE. In this case, the relaxed PDSCH processing time may not be applied.

[0319] Frequency Hopping Method for BWP and Sub-BWP

[0320] The BS can separately configure the initial UL / DL BWP for the UE in the RRC_IDLE or RRC_INACTIVE state as multiple overlapping or non-overlapping sub-BWPs. The BS can separately configure one or more UL / DL BWPs for the UE in the RRC_CONNECTED state as multiple overlapping or non-overlapping sub-BWPs.

[0321] In this way, when the active BWP of the UE is separately configured as multiple overlapping or non-overlapping sub-BWPs, the UE can receive PDCCH and / or PDSCH and / or reference signals from a sub-BWP of one BWP at a time (a specific time) through multiple sub-BWPs in the active DL BWP based on a specific frequency hopping pattern, and can transmit PUCCH and / or PUSCH and / or sounding reference signal (SRS) from a sub-BWP of one BWP at a time (a specific time) through multiple sub-BWPs in the active UL BWP based on a specific frequency hopping pattern. The UE in the RRC_IDLE or RRC_INACTIVE state can select a sub-BWP (or an initial active sub-BWP) based on the frequency hopping pattern from the initial DL BWP, can receive paging, system information or RACH MSG2 / MSG4 / MSGB, and can transmit RACH MSG1 / MSGA / MSG3 by selecting a sub-BWP (or an initial active sub-BWP) based on the frequency hopping pattern from the initial UL BWP.

[0322] In the method based on the frequency hopping pattern, the frequency hopping pattern may include one or more of the following options.

[0323] >The BS can transmit configuration information about one or more hopping patterns and the ID of each of the multiple hopping patterns through an RRC message, and can transmit indication information indicating the ID of the hopping pattern to be applied through an RRC message (MAC CE or DCI). The UE can receive the configuration information, and when the ID is indicated by the indication information, the UE can perform the following operations.

[0324] - When frequency hopping is not currently applied / executed, the UE can transmit and receive signals based on the frequency hopping pattern indicating the ID.

[0325] - When frequency hopping is currently applied / executed, the UE can change the frequency hopping pattern to the frequency hopping pattern indicating the ID and perform signal transmission / reception.

[0326] - After a certain time after receiving the ID, the transmission and reception operations of the signals can be performed based on the frequency hopping pattern according to the ID. Here, the certain time can be specified / determined based on the UE capability or indicated / determined through the RRC configuration of the BS.

[0327] >The BS and the UE can configure the frequency hopping pattern of a 5 MHz frequency period or a 5 MHz frequency bandwidth (i.e., sub-BWP) based on the symbol index, slot index, subframe index, and / or SFN index as follows.

[0328] - The BS can connect / map at least one BWP (and / or at least one sub - BWP) to a specific symbol index, a specific time - slot index, a specific sub - frame index, and / or a specific SFN index in a hopping mode. Alternatively, the BS can connect / map a specific BWP and / or a specific sub - BWP to at least one symbol index, at least one time - slot index, at least one sub - frame index, and / or at least one SFN index. In this way, by connecting different BWPs (and / or different sub - BWPs) for each symbol index, time - slot index, sub - frame index, and / or SFN index (in this mode), the BS can configure a frequency - hopping mode for frequency hopping between BWPs (and / or sub - BWPs) over time. When the frequency - hopping mode is configured in this way, the PDSCH or PUSCH resources scheduled by DCI can be allocated to the UE based on the sub - BWP connected to the specific symbol index, specific time - slot index, specific sub - frame index, and / or specific SFN index.

[0329] - For example, when the UE receives DCI in the first time - slot of the first sub - frame, the UE can transmit the PUSCH (or receive the PDSCH) scheduled by the DCI in the first sub - BWP of the first BWP. Alternatively, when the UE receives DCI in the second time - slot of the first sub - frame, the UE can transmit the PUSCH (or receive the PDSCH) scheduled by the DCI in the second sub - BWP of the first or second BWP. In this case, the UE can transmit the PUSCH or receive the PDSCH based on the frequency - hopping mode. In this way, the phenomenon of resource concentration on a specific frequency or a specific sub - BWP (or the phenomenon of resource concentration and allocation) can be solved.

[0330] When the frequency - hopping mode is configured, the UE can transmit and receive signals as follows.

[0331] - When the DCI received in the first time - slot indicates that the PDSCH is to be transmitted in the second time - slot, the UE can determine the BWP and / or sub - BWP of the second time - slot according to the configured frequency - hopping mode, and determine the PDSCH resources in the determined sub - BWP of the determined BWP to receive the PDSCH. Here, the first time - slot and the second time - slot can be the same or different.

[0332] - When the DCI received in the first time - slot indicates that the PUSCH is to be transmitted in the second time - slot, the UE can determine the BWP and / or sub - BWP of the second time - slot according to the configured frequency - hopping mode, and transmit the PUSCH based on the PUSCH resources allocated in the determined sub - BWP of the determined BWP. Here, the first time - slot and the second time - slot can be the same or different.

[0333] - When a specific semi-persistent scheduling (SPS) is activated, the UE can determine the BWP and / or sub-BWP of the time slot for allocating the corresponding SPS PDSCH according to the configured frequency hopping pattern, and receive the SPS PDSCH in the SPS PDSCH resources allocated in the determined sub-BWP of the determined BWP.

[0334] - When a specific configured grant (CG) is activated, the UE can determine the BWP and / or sub-BWP of the time slot for allocating the corresponding CG PUSCH according to the configured frequency hopping pattern, and transmit the CG PUSCH based on the CG PUSCH resources allocated in the determined sub-BWP of the determined BWP.

[0335] R-SIB1 Reception for Rel.18 R-UE

[0336] Rel.18 R-UE receives the Rel.18 PDSCH for transmitting system information according to Methods 1, 2, and 3. In this case, the DCI of Methods 1, 2, and 3 is the DCI with a CRC scrambled by SI-RNTI.

[0337] When the Rel.18 PDSCH transmits the Rel.18 R-UE R-SIB1, the DCI can schedule the Rel.18 PDSCH for R-SIB1 as follows.

[0338] (1) Option 1: A DCI on the CORESET shared by the UE prior to Rel.18 and the Rel.18 UE schedules the SIB1 prior to Rel.18 and the Rel.18 R-SIB1 within the initial DL BWP of 20 MHz using FDM.

[0339] (2) Option 2: A DCI on the CORESET shared by the UE prior to Rel.18 and the Rel.18 UE schedules the SIB1 prior to Rel.18 within the initial DL BWP of 20 MHz and the Rel.18 R-SIB1 outside the initial DL BWP of 20 MHz using FDM.

[0340] (3) Option 3: A DCI on the CORESET shared by the UE prior to Rel.18 and the Rel.18 UE schedules the SIB1 prior to Rel.18 and the Rel.18 R-SIB1 within the initial DL BWP of 20 MHz using TDM. In Option 3, the Rel.18 PDSCH for transmitting the Rel.18 R-SIB1 is scheduled within a 5 MHz (sub)BWP or BW position, but the legacy PDSCH for transmitting the SIB1 prior to Rel.18 is scheduled within the initial BWP of 5 MHz or the initial BWP of 20 MHz.

[0341] Similar to the option, the BS can indicate via DCI or MIB whether the DCI schedules both Rel.18 R-SIB1 and SIB1 prior to Rel.18.

[0342] When the Rel.18 R-UE receives DCI for scheduling the regular SIB1 or the regular SIB1, the Rel.18 R-UE receives a separate cellBarred parameter for the Rel.18 R-UE from the regular SIB1 or the DCI for scheduling the regular SIB1. According to the received cellBarred parameter, it is determined whether the Rel.18 R-UE can access the corresponding cell or whether the cell needs to be prohibited.

[0343] When the Rel.18 R-UE receives the new R-SIB1 or DCI for scheduling the R-SIB1 without receiving the regular SIB1, the Rel.18 R-UE selects a sub-BWP for the R-SIB1 and selects the DCI of the selected sub-BWP or a separate cellBarred parameter for the Rel.18 R-UE from the R-SIB1. According to the received cellBarred parameter, it is determined whether the Rel.18 R-UE can access the corresponding cell or whether the cell needs to be prohibited.

[0344] When on-demand SI is configured, the BS can configure dedicated RACH resources for the on-demand SI request. Alternatively, the dedicated RACH resources can be configured for the terminal identification during the initial access. Therefore, for the on-demand SI request or for the terminal identification during the initial access, the BS differentiates and assigns RACH resources for Rel.17 R-UEs, RACH resources for Rel.18 R-UEs, and RACH resources for ordinary terminals. In this case, the BS can classify and allocate RACH resources for option BW1 terminals, RACH resources for option BW2 terminals, and RACH resources for option BW3 terminals. These different RACH resources can be separately allocated through the existing SIB1 and R-SIB1. In this case, the Rel.18 R-UE selects a PRACH resource suitable for its terminal type and sends MSG1 or MSGA. Additionally, the Rel.18 R-UE can indicate through the (sub)header of the MAC PDU of MSG3 PUSCH or MSGA PUSCH, or options BW1, BW2, or BW3 can be indicated according to the terminal type.

[0345] Paging Reception for Rel.18 R-UE

[0346] The Rel.18 R-UE receives the Rel.18 PDSCH for sending the paging message according to Methods 1, 2, and 3. In this case, the DCI of Methods 1, 2, and 3 is the DCI with a CRC scrambled by P-RNTI.

[0347] The DCI for PEI, rather than the DCI in methods 1, 2, and 3, may indicate the (sub)BWP for the R-UE or the BW position for receiving the Rel.18 paging PDSCH. Alternatively, the DCI for PEI, rather than the DCI in methods 1, 2, and 3, may provide FDRA and / or TDRA information for receiving Rel.18 paging.

[0348] When the TRS for paging is configured for Rel.18 R-UE, the Rel.18 TRS may be configured as follows.

[0349] (1) Option 1: The TRS for paging the Rel.18 R-UE is only configured within the initial BWP, sub-BWP, or BW position of 5 MHz for the Rel.18 R-UE.

[0350] When the TRS for the Rel.18 R-UE performs frequency hopping, the corresponding TRS only performs frequency hopping within the initial BWP, sub-BWP, or BW position of 5 MHz for the Rel.18 R-UE.

[0351] (2) Option 2: The TRS for paging the Rel.18 R-UE may be configured outside the initial BWP, sub-BWP, or BW position of 5 MHz. In this case, the TRS is configured within the initial BWP of the 20 MHz Rel.17 R-UE.

[0352] The Rel.18 R-UE (especially the terminal of option BW1 or BW2) receives the TRS through RF retuning.

[0353] Figure 12 It is a schematic diagram for explaining the method by which the UE performs the RACH procedure to send a signal to a specific cell or BS.

[0354] Referring to Figure 12 , the UE may send a first message (S121) for performing the random access channel (RACH) procedure for a specific cell. For example, the first message may be MSG1 including the PRACH preamble in the 4-step RACH, or MSGA including the PRACH preamble and PUSCH in the 2-step RACH.

[0355] Then, the UE may receive a second message in response to the first message from a specific cell (S123). Here, the second message may be MSG2 and / or MSG4 of a 4-step RACH, or MSGB of a 2-step RACH. For example, MSGB may correspond to a Random Access Response (RAR) message and may include an MSGB PDCCH (sent via PDCCH or for PDCCH) and an MSGB PDSCH (sent via PDSCH or for PDSCH). For example, MSGB may be a successful Random Access Response (RAR) message.

[0356] Then, the UE may transmit a Physical Uplink Control Channel (PUCCH) including a Hybrid Automatic Repeat reQuest - ACK (HARQ-ACK) related to the second message based on a specific minimum time interval (S125). For example, when the second message includes a successful Random Access Response (RAR) (or if the PDSCH included in the second message includes a successful RAR), the UE may transmit a PUCCH including HARQ-ACK information for the successful RAR or PDSCH.

[0357] As described in the table with the content of "PDSCH Processing / HARQ Feedback Time Relaxation Method during Initial Access", during the initial access procedure where the UE capability is unknown, the sub - BWP to be selected by the UE is unknown, and thus an R18 R-UE may receive MSGB or MSG4 for a bandwidth exceeding 5 MHz (e.g., 20 MHz). In this case, the R18 R-UE may not be able to transmit the HARQ-ACK for the PDSCH included in MSGB within the minimum time interval required by a normal UE (i.e., without bandwidth limitation) due to its limited processing capability for PDSCH, etc. Therefore, as described below, relaxation of the PUCCH transmission for reporting the HARQ-ACK received for the MSGB PDSCH may be required.

[0358] Specifically, when the time interval between the last symbol of the PDSCH related to the second message and the first symbol of the PUCCH is not less than a specific minimum time, the UE may transmit a PUCCH including HARQ-ACK information. For example, when the time interval between the first symbol of the transmission time resource of the PUCCH determined / indicated based on the DCI / PDCCH related to the second message (or the PDCCH included in the second message) and the last symbol of the PDSCH scheduled by the DCI / PDCCH is longer than the specific minimum time, the UE may transmit a PUCCH including HARQ-ACK for the PDSCH. In contrast, when the interval between the last symbol of the PDSCH and the first symbol of the PUCCH is smaller than the specific minimum time interval, the UE may perform the RACH procedure again without transmitting a PUCCH including HARQ-ACK for the PDSCH.

[0359] Here, the specific minimum time interval may vary depending on whether the UE is a first UE (or R18 R-UE, or first UE type) with a bandwidth limited to a first size (e.g., 5 MHz) as described in option 2A, 2B, or 2C above, or a second UE (or R17 R-UE with a bandwidth limited to 20 MHz, or a normal UE without bandwidth limitation, or second UE type). Specifically, the specific minimum time interval may be the sum of the processing time (N T,1 ) of the physical downlink shared channel (PDSCH) according to the UE capability and a specific time. In this case, the specific time may be configured differently depending on whether the UE is a first UE with a bandwidth limited to a first size (e.g., 5 MHz) as described in option 2A, 2B, or 2C above, or a second UE with a bandwidth not limited to the first size. For example, based on the fact that the UE is a first UE supporting a restricted bandwidth of a first size or smaller, the specific time may be configured as a second specific time longer than a first specific time used for a second UE not supporting a restricted bandwidth of a first size or smaller. That is, when the UE is a first UE, the UE may have a longer specific time than when the UE is a second UE (alternatively, when the UE is a first terminal, it may be configured with a longer specific time than when the UE is a second UE), and when the UE is a second UE, the UE may have a longer specific minimum time interval (a longer specific minimum time interval may be configured than when the UE is a second UE).

[0360] For example, the first specific time may be 0.5 milliseconds as described above, and the second specific time may be a time longer than 0.5 milliseconds (e.g., 1.0 millisecond or 1.5 milliseconds). The second specific time may be configured as 1 millisecond or 1.5 milliseconds based on the subcarrier spacing (SCS) size of the PDSCH. For example, when the subcarrier spacing (SCS) size is 15 KHz, the second specific time may be configured as 1.5 milliseconds. Alternatively, when the SCS size is 30 KHz, the second specific time may be configured as 1 millisecond.

[0361] Alternatively, as described in Option 2C, the transmission time slot of the PUCCH may be determined based on the value indicated by the HARQ feedback timing indicator field included in the successful RAR and the time slot offset configured separately for the first UE. Here, the time slot offset may be configured via SystemInformationBlockType1 (SIB1) or system information (SI).

[0362] Figure 13 is a schematic diagram for explaining the method by which the BS receives signals from the UE that performs the RACH procedure.

[0363] Referring to Figure 13 , the BS may receive a first message (S131) from the UE for performing a random access channel (RACH) procedure. For example, the first message may be MSG1 including a PRACH preamble in a 4-step RACH, or MSGA including a PRACH preamble and data (PUSCH) in a 2-step RACH.

[0364] Then, the BS may send a second message (S133) in response to the first message. Here, the second message may be MSG2 and / or MSG4 in a 4-step RACH, or MSGB in a 2-step RACH.

[0365] Then, the BS may receive a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message transmitted based on a specific minimum time interval (S135). For example, when the BS sends a second message including a successful random access response (RAR), the BS may receive a PUCCH including HARQ-ACK information for the successful RAR or PDSCH from the terminal.

[0366] As described in the table with the content of "PDSCH Processing / HARQ Feedback Time Relaxation Method During Initial Access", when the UE is an R-18R-UE (or the first terminal), it may be necessary to relax the transmission of the PUCCH that reports the HARQ-ACK for the MSGB PDSCH reception.

[0367] Specifically, when the time interval between the last symbol of the PDSCH related to the second message and the first symbol of the PUCCH (e.g., the first symbol of the transmission time interval of the PUCCH indicated / assigned by the BS) is not less than a specific minimum time, the BS can receive the PUCCH including HARQ-ACK information. For example, when the time interval between the first symbol of the transmission time resource of the PUCCH determined / indicated based on the DCI / PDCCH related to the second message (or the PDCCH included in the second message) and the last symbol of the PDSCH scheduled by the DCI / PDCCH is longer than the specific minimum time, the BS can receive the PUCCH including the HARQ-ACK for the PDSCH. In contrast, when the interval between the last symbol of the PDSCH and the first symbol of the PUCCH is smaller than the specific minimum time interval, the BS can not receive the PUCCH including the HARQ-ACK for the PDSCH.

[0368] Here, the specific minimum time interval can be different depending on whether the UE is a first UE (or R18 R-UE) with a bandwidth restricted to a first size (e.g., 5 MHz) as described in the above options 2A, 2B, or 2C, or a second UE (or R17 R-UE with a bandwidth restricted to 20 MHz, or a normal UE without bandwidth restriction). Specifically, the specific minimum time interval can be the sum of the processing time (N T,1 ) of the physical downlink shared channel (PDSCH) according to the UE capability and a specific time. In this case, the specific time can be configured differently depending on whether the UE is a first UE with a bandwidth restricted to a first size (e.g., 5 MHz) as described in the above options 2A, 2B, or 2C, or a second UE with a bandwidth not restricted to the first size. For example, based on the fact that the UE is a first UE with a restricted bandwidth of the first size or smaller, the specific time can be configured as a second specific time longer than a first specific time used for a second UE with a bandwidth not restricted to the first size. That is, when the UE is a first UE, the UE can have a longer specific time than when the UE is a second UE (or when the UE is a first terminal, it can be configured with a longer specific time than when the UE is a second UE), and when the UE is a second UE, the UE can have a longer specific minimum time interval (a longer specific minimum time interval can be configured than when the UE is a second UE).

[0369] For example, the first specific time may be 0.5 milliseconds as described above, and the second specific time may be a time longer than 0.5 milliseconds (e.g., 1.0 millisecond or 1.5 milliseconds). The second specific time may be configured as 1 millisecond or 1.5 milliseconds based on the subcarrier spacing (SCS) size of the PDSCH. For example, when the subcarrier spacing (SCS) size is 15 KHz, the second specific time may be configured as 1.5 milliseconds. Alternatively, when the SCS size is 30 KHz, the second specific time may be configured as 1 millisecond.

[0370] In this way, by configuring the minimum time interval of the R18 R-UE restricted to a specific bandwidth during the RACH procedure to be longer than that of a normal UE not restricted to a specific bandwidth, sufficient time can be provided for the R18 R-UE to transmit the PUCCH including the HARQ-ACK for the PDSCH included in MSGB or MSG4. Alternatively, by controlling the minimum time interval, even during the initial access procedure when the UE capabilities are unknown and MSGB or MSG4 is received in a bandwidth exceeding a specific bandwidth, the R18 R-UE can effectively transmit the PUCCH including the HARQ-ACK for MSGB or MSG4. Alternatively, by effectively transmitting the PUCCH including the HARQ-ACK for MSGB or MSG4, the success rate of the RACH procedure of the R18 R-UE can be significantly improved.

[0371] Figure 14 Fig. 1 shows a communication system 1 to which the present disclosure is applied.

[0372] Refer to Figure 14, the communication system 1 applied to the present disclosure includes a wireless device, a base station (BS), and a network. Herein, the wireless device refers to a device that performs communication using a radio access technology (RAT) (e.g., 5G new RAT (NR) or Long Term Evolution (LTE)), and may be referred to as a communication / radio / 5G device. The wireless device may include (but is not limited to) a robot 100a, vehicles 100b-1 and 100b-2, an extended reality (XR) device 100c, a handheld device 100d, a household appliance 100e, an Internet of Things (IoT) device 100f, and an artificial intelligence (AI) device / server 400. For example, the vehicle may include a vehicle with wireless communication capabilities, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. Herein, the vehicle may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device may include an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device, and may be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) installed in a vehicle, a TV, a smart phone, a computer, a wearable device, a household appliance device, a digital sign, a vehicle, a robot, etc. The handheld device may include a smart phone, a smart board, a wearable device (e.g., a smart watch or smart glasses), and a computer (e.g., a notebook). The household appliance may include a TV, a refrigerator, and a washing machine. The IoT device may include sensors and smart meters. For example, the BS and the network may be implemented as wireless devices, and a specific wireless device 200a may operate as a BS / network node relative to other wireless devices.

[0373] The wireless devices 100a to 100f may be connected to the network 300 via the BS 200. AI technology may be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f may be connected to the AI server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices 100a to 100f may communicate with each other through the BS 200 / network 300, the wireless devices 100a to 100f may perform direct communication (e.g., sidelink communication) with each other without passing through the BS / network. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). The IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0374] Wireless communications / connections 150a, 150b, or 150c can be established between wireless devices 100a to 100f / BS200 or between BS200 / BS200. In this document, wireless communications / connections can be established via various RATs (e.g., 5G NR) such as uplink / downlink communication 150a, sidelink communication 150b (or D2D communication), or inter-BS communication (e.g., relay, integrated access backhaul (IAB)). The wireless device and the BS / wireless device can send / receive radio signals to / from each other via wireless communications / connections 150a and 150b. For example, wireless communications / connections 150a and 150b can send / receive signals via various physical channels. To this end, at least a part of the various configuration information for configuring processes for sending / receiving radio signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation processes can be executed based on various proposals of the present disclosure.

[0375] Figure 15 Shows a wireless device applicable to the present disclosure.

[0376] Referring to Figure 15 , the first wireless device 100 and the second wireless device 200 can send radio signals via various RATs (e.g., LTE and NR). In this document, {the first wireless device 100 and the second wireless device 200} can correspond to Figure 14 {wireless device 100x and BS200} and / or {wireless device 100x and wireless device 100x} of

[0377] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may control the memory 104 and / or the transceiver 106, and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. For example, the processor 102 may process the information in the memory 104 to generate first information / signals, and then transmit radio signals including the first information / signals through the transceiver 106. The processor 102 may receive radio signals including second information / signals through the transceiver 106, and then store the information obtained by processing the second information / signals in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memory 104 may store software codes including commands for executing part or all of the processes controlled by the processor 102 or for executing the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. Herein, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 may be connected to the processor 102 and transmit and / or receive radio signals through one or more antennas 108. Each transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used interchangeably with the radio frequency (RF) unit. In this disclosure, the wireless device may represent a communication modem / circuit / chip.

[0378] According to an example, the first wireless device 100 or the UE may include a processor 102 and a memory 104 connected to an RF transceiver. The memory 104 may include at least one program for performing operations related to the embodiments described with reference to Figures 9 to 13 the embodiments.

[0379] Specifically, the processor 102 may control the RF transceiver 106: to transmit a first message for performing a random access channel (RACH) procedure for a specific cell; to receive a second message in response to the first message from the specific cell; and to transmit a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message based on a specific minimum time interval. Here, the specific minimum time interval is the sum of the physical downlink shared channel (PDSCH) processing time according to the UE capability and a specific time, and based on the UE being a first UE whose bandwidth is limited to a first size, the specific time may be configured as a second specific time longer than a first specific time of a second UE whose bandwidth is not limited to the first size.

[0380] Alternatively, the processor 102 and the memory 104 may be a processing device that controls a UE that communicates with a BS / specific cell. In this case, the processing device may include: at least one processor; and at least one memory connected to the at least one processor and storing instructions, wherein when the at least one processor executes the instructions, the UE is caused to: transmit a first message for performing a random access channel (RACH) procedure for a specific cell; receive a second message in response to the first message from the specific cell; and transmit a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgment (HARQ-ACK) related to the second message based on a specific minimum time interval. Here, the specific minimum time interval is the sum of the physical downlink shared channel (PDSCH) processing time according to the UE capability and a specific time, and based on the UE being a first UE whose bandwidth is limited to a first size, the specific time may be configured as a second specific time that is longer than a first specific time of a second UE whose bandwidth is not limited to the first size.

[0381] Alternatively, a non-transitory computer-readable storage medium may be configured, on which instructions for performing the proposed method described with reference to Figures 9 to 13 are recorded.

[0382] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206, and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. For example, the processor 202 may process the information in the memory 204 to generate third information / signals, and then transmit radio signals including the third information / signals through the transceiver 206. The processor 202 may receive radio signals including fourth information / signals through the transceiver 206, and then store the information obtained by processing the fourth information / signals in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software codes including commands for executing some or all of the processes controlled by the processor 202 or for implementing the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. Herein, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 206 may be connected to the processor 202 and transmit and / or receive radio signals through one or more antennas 208. Each transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used interchangeably with the RF unit. In this disclosure, the wireless device may represent a communication modem / circuit / chip.

[0383] In the following, the hardware components of wireless devices 100 and 200 will be described in more detail. One or more protocol layers may be implemented by (but not limited to) one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, and SDAP). One or more processors 102 and 202 may generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document, and provide the generated signals to one or more transceivers 106 and 206. One or more processors 102 and 202 may receive signals (e.g., baseband signals) from one or more transceivers 106 and 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document.

[0384] One or more processors 102 and 202 may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processor devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field-programmable gate arrays (FPGAs) may be included in one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be configured to include modules, processes, or functions. The firmware or software configured to execute the descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document may be included in one or more processors 102 and 202 or stored in one or more memories 104 and 204 to be driven by one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document may be implemented using firmware or software in the form of code, commands, and / or command sets.

[0385] One or more memories 104 and 204 may be connected to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and / or commands. One or more memories 104 and 204 may be configured by read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard disk drive, register, cache memory, computer-readable storage medium, and / or combinations thereof. One or more memories 104 and 204 may be located inside and / or outside one or more processors 102 and 202. One or more memories 104 and 204 may be connected to one or more processors 102 and 202 by various techniques such as wired or wireless connections.

[0386] One or more transceivers 106 and 206 may send user data, control information, and / or radio signals / channels mentioned in the methods and / or operational flowcharts of this document to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and send and receive radio signals. For example, one or more processors 102 and 202 may execute controls such that one or more transceivers 106 and 206 may send user data, control information, or radio signals to one or more other devices. One or more processors 102 and 202 may execute controls such that one or more transceivers 106 and 206 may receive user data, control information, or radio signals from one or more other devices. One or more transceivers 106 and 206 may be connected to one or more antennas 108 and 208, and one or more transceivers 106 and 206 may be configured to send and receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document through one or more antennas 108 and 208. In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106 and 206 may convert the received radio signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, radio signals / channels, etc. using one or more processors 102 and 202. One or more transceivers 106 and 206 may convert the user data, control information, radio signals / channels, etc. processed using one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more transceivers 106 and 206 may include (analog) oscillators and / or filters.

[0387] Figure 16 is a diagram showing the DRX operation of a UE according to an embodiment of the present disclosure.

[0388] The UE can perform DRX operations in the processes and / or methods described / proposed above. A UE configured with DRX can reduce power consumption by receiving DL signals discontinuously. DRX can be performed in the RRC_IDLE state, RRC_INACTIVE state, and RRC_CONNECTED state. The UE performs DRX in the RRC_IDLE state and RRC_INACTIVE state to receive paging signals discontinuously. The DRX in the RRC_CONNECTED state (RRC_CONNECTED DRX) will be described below.

[0389] The DRX cycle includes an on-duration and a DRX opportunity. The DRX cycle defines the time interval between periodic repetitions of the on-duration. The on-duration is the time period during which the UE monitors the PDCCH. When the UE is configured with DRX, the UE performs PDCCH monitoring during the on-duration. When the UE successfully detects the PDCCH during PDCCH monitoring, the UE starts an inactivity timer and remains awake. In contrast, when the UE fails to detect any PDCCH during PDCCH monitoring, the UE transitions to the sleep state after the on-duration. Therefore, when DRX is configured, PDCCH monitoring / reception can be performed discontinuously in the time domain in the processes and / or methods described / proposed above. For example, when DRX is configured, the PDCCH reception timing (e.g., the time slot with PDCCH SS) can be configured discontinuously according to the DRX configuration in the present disclosure. In contrast, when DRX is not configured, PDCCH monitoring / reception can be performed continuously in the time domain. For example, when DRX is not configured, the PDCCH reception timing (e.g., the time slot with PDCCH SS) can be configured continuously in the present disclosure. Regardless of whether DRX is configured, PDCCH monitoring can be restricted during the time period configured as a measurement gap.

[0390] The above embodiments are combinations of elements and features of the present disclosure in specific forms. Unless otherwise mentioned, these elements or features can be considered selective. Each element or feature can be implemented without being combined with other elements or features. In addition, embodiments of the present disclosure can be configured by combining some elements and / or some features. The operation order described in the embodiments of the present disclosure can be rearranged. Some structures or features of any one embodiment can be included in another embodiment, or can be replaced with the corresponding structures or features of another embodiment. Obviously, the claims that are not explicitly cited in the appended claims can be presented as combinations of embodiments of the present disclosure, or can be included as new claims through subsequent modifications after the application is filed.

[0391] Those skilled in the art will understand that the present disclosure can be implemented in other specific ways different from the ways described herein without departing from the spirit and basic characteristics of the present disclosure. Therefore, the above embodiments are to be construed in all respects as illustrative and not restrictive. The scope of the present disclosure should be determined by the appended claims and their legal equivalents, rather than by the above description, and all changes falling within the meaning and scope of equivalence of the appended claims should be included therein.

[0392] Industrial applicability

[0393] The present disclosure can be used in a UE, a base station, or other devices of a wireless mobile communication system.

Claims

1. A method for a user equipment (UE) to transmit a signal in a wireless communication system, the method comprising the steps of: Transmitting a first message for performing a random access channel (RACH) procedure for a specific cell; Receiving, from the specific cell, a second message in response to the first message; and Transmitting a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message based on a specific minimum time interval, wherein the specific minimum time interval is the sum of a processing time of a physical downlink shared channel (PDSCH) according to the capabilities of the UE and a specific time, and wherein, based on the UE being a first UE whose bandwidth is restricted to a first size, the specific time is configured as a second specific time that is longer than a first specific time for a second UE whose bandwidth is not restricted to the first size.

2. The method according to claim 1, wherein Transmitting the PUCCH based on a time interval between a last symbol of the PDSCH for the second message and a first symbol of the PUCCH being not less than the specific minimum time.

3. The method according to claim 1, wherein The second specific time is set to a time longer than the first specific time of 0.5 milliseconds.

4. The method according to claim 2, wherein The PDSCH includes a successful random access response (RAR) for the UE.

5. The method according to claim 2, wherein, Configuring the second specific time as 1 millisecond or 1.5 milliseconds based on a subcarrier spacing (SCS) size of the PDSCH related to the second message.

6. The method according to claim 5, wherein Configuring the second specific time as 1.5 milliseconds based on the SCS size being 15 KHz.

7. The method according to claim 5, wherein, Configuring the second specific time as 1 millisecond based on the SCS size being 30 KHz.

8. The method according to claim 1, wherein, The second message includes a successful random access response (RAR), and wherein, based on the UE being the first UE, a transmission time slot of the PUCCH is determined based on a value indicated by a HARQ feedback timing indicator field included in the successful RAR and a time slot offset separately configured for the first UE.

9. The method according to claim 8, wherein The time slot offset is configured by System Information Block Type 1 (SIB1) or system information (SI).

10. The method according to claim 1, wherein The first UE is a first reduced-capability RedCap type UE capable of performing communication in a restricted bandwidth of 5 MHz, and wherein the second UE is a second RedCap type UE capable of performing communication in a restricted bandwidth of 20 MHz.

11. A non-transitory computer-readable storage medium storing instructions for performing the method according to claim 1.

12. A user equipment (UE) for receiving a signal in a wireless communication system, the UE comprising: A radio frequency (RF) transceiver; And A processor connected to the RF transceiver, Wherein, the processor controls the RF transceiver to: send a first message for performing a random access channel (RACH) procedure for a specific cell; receive a second message in response to the first message from the specific cell; and send a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message based on a specific minimum time interval. Wherein, the specific minimum time interval is the sum of the processing time of a physical downlink shared channel (PDSCH) according to the capabilities of the UE and a specific time, and wherein, based on the UE being a first UE whose bandwidth is restricted to a first size, the specific time is configured as a second specific time that is longer than a first specific time for a second UE whose bandwidth is not restricted to the first size.

13. A processing apparatus for controlling a user equipment (UE) to receive signals in a wireless communication system, the processing apparatus comprising: at least one processor; and at least one memory coupled to the at least one processor and storing instructions, wherein, the instructions cause the UE to: send a first message for performing a random access channel (RACH) procedure for a specific cell; receive a second message in response to the first message from the specific cell; and send a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message based on a specific minimum time interval. Wherein, the specific minimum time interval is the sum of the processing time of a physical downlink shared channel (PDSCH) according to the capabilities of the UE and a specific time, and wherein, based on the UE being a first UE whose bandwidth is restricted to a first size, the specific time is configured as a second specific time that is longer than a first specific time for a second UE whose bandwidth is not restricted to the first size.

14. A method for a base station to receive signals in a wireless communication system, the method comprising the steps of: receiving, from a user equipment (UE), a first message for performing a random access channel (RACH) procedure; sending a second message in response to the first message; and receiving, based on a specific minimum time interval, a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message, wherein, the specific minimum time interval is the sum of the processing time of a physical downlink shared channel (PDSCH) according to the capabilities of the UE and a specific time, and wherein, based on the UE being a first UE whose bandwidth is restricted to a first size, the specific time is set as a second specific time that is longer than a first specific time for a second UE whose bandwidth is not restricted to the first size.

15. A base station (BS) for receiving signals in a wireless communication system, the BS comprising: a radio frequency (RF) transceiver; and a processor connected to the RF transceiver. Wherein, the processor controls the RF transceiver to: receive a first message for performing a random access channel (RACH) procedure from a user equipment (UE); transmit a second message in response to the first message; and receive, based on the specific minimum time interval, a physical uplink control channel (PUCCH) including a hybrid automatic repeat request acknowledgement (HARQ-ACK) related to the second message, wherein, the specific minimum time interval is the sum of a processing time of a physical downlink shared channel (PDSCH) according to the capability of the UE and a specific time, and wherein, based on the UE being a first UE whose bandwidth is restricted to a first size, the specific time is set to a second specific time that is longer than a first specific time for a second UE whose bandwidth is not restricted to the first size.

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