Method and device for uplink transmission or reception in wireless communication system

Abstract

A method and a device for uplink transmission or uplink reception in a wireless communication system are disclosed. The method according to one embodiment of the present disclosure may comprise steps in which a terminal: receives, from a first network node, first information related to a synchronization signal / physical broadcast channel block (SSB) of a first network node and / or a reference signal (RS) of the first network node; transmits a random access preamble to a second network node on the basis of the first information; and receives, from the second network node, a random access response (RAR) responding to the random access preamble. The RAR can include second information related to a timing advance (TA) for the second network node.

Description

Method and device for uplink transmission or reception in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and device for uplink transmission or uplink reception in a wireless communication system.

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, they have expanded beyond voice to include data services. Currently, explosive growth in traffic is leading to resource shortages and users' demand for higher-speed services, necessitating a more advanced mobile communication system.

[0003] Next-generation mobile communication systems must support explosive data traffic growth, dramatically increasing data rates per user, a vastly increased number of connected devices, ultra-low end-to-end latency, and high energy efficiency. To achieve these goals, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

[0004] The technical problem of the present disclosure is to provide a method and device for uplink transmission of a terminal or uplink reception of a base station in a network including an uplink reception point.

[0005] An additional technical problem of the present disclosure is to provide a method and device for obtaining timing advance for an uplink reception point of a terminal or for a base station to provide timing advance for an uplink reception point to a terminal.

[0006] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0007] A method according to one aspect of the present disclosure may include: receiving, by a terminal, from a first network node, first information related to at least one of a synchronization signal / physical broadcast channel block (SSB) of a first network node or a reference signal (RS) of the first network node; transmitting, by the terminal, to a second network node, a random access preamble based on the first information; and receiving, by the terminal, from the first network node, a random access response (RAR) in response to the random access preamble. The RAR may include second information related to a timing advance (TA) for the second network node.

[0008] A method according to an additional aspect of the present disclosure may include: transmitting, by the first network node, to a terminal, first information related to at least one of a synchronization signal / physical broadcast channel block (SSB) of the first network node or a reference signal (RS) of the first network node; and transmitting, by the first network node, to the terminal, a random access response (RAR) in response to a random access preamble transmitted by the terminal to a second network node based on the first information. The RAR may include second information related to a timing advance (TA) for the second network node.

[0009] According to the present disclosure, a method and device for uplink transmission by a terminal or uplink reception by a base station in a network including an uplink reception point can be provided.

[0010] According to the present disclosure, a method and device for obtaining timing advance for an uplink reception point of a terminal or for providing timing advance for an uplink reception point to a terminal by a base station can be provided.

[0011] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0012] The accompanying drawings, which are incorporated in and are part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe the technical features of the present disclosure.

[0013] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0014] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0015] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0016] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied.

[0017] FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0018] FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

[0019] FIG. 7 is a diagram illustrating an uplink-downlink timing relationship in a wireless communication system to which the present disclosure can be applied.

[0020] FIG. 8 illustrates a MAC CE for a random access response in a wireless communication system to which the present disclosure can be applied.

[0021] FIG. 9 illustrates a timing advance command MAC CE in a wireless communication system to which the present disclosure can be applied.

[0022] FIG. 10 is a diagram illustrating the operation of a terminal according to one embodiment of the present disclosure.

[0023] FIG. 11 is a diagram illustrating the operation of a base station according to one embodiment of the present disclosure.

[0024] FIG. 12 is a block diagram illustrating a wireless communication device according to one embodiment of the present disclosure.

[0025] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

[0026] In some cases, to avoid obscuring the concepts of the present disclosure, known structures and devices may be omitted or illustrated in block diagram form focusing on the core functions of each structure and device.

[0027] In the present disclosure, when a component is said to be "connected," "coupled," or "connected" to another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0028] In this disclosure, terms such as “first,” “second,” etc. are used only to distinguish one component from another and are not used to limit the components, and do not limit the order or importance between the components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0029] The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" as used herein may refer to any one of the associated enumerated items, or is meant to refer to and encompass any and all possible combinations of two or more of them. Furthermore, the use of " / " between words in this disclosure has the same meaning as "and / or" unless otherwise stated.

[0030] The present disclosure describes a wireless communication network or a wireless communication system, and an operation performed in a wireless communication network may be performed in a process of controlling the network and transmitting or receiving a signal from a device (e.g., a base station) that manages the wireless communication network, or may be performed in a process of transmitting or receiving a signal to or between terminals connected to the wireless network.

[0031] In the present disclosure, transmitting or receiving a channel means transmitting or receiving information or a signal through the channel. For example, transmitting a control channel means transmitting control information or a signal through the control channel. Similarly, transmitting a data channel means transmitting data information or a signal through the data channel.

[0032] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In downlink, a transmitter may be part of a base station, and a receiver may be part of a terminal. In uplink, a transmitter may be part of a terminal, and a receiver may be part of a base station. A base station may be expressed as a first communication device, and a terminal may be expressed as a second communication device. A base station (BS) may be replaced by terms such as a fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), access point (AP: Access Point), network (5G network), AI (Artificial Intelligence) system / module, RSU (road side unit), robot, drone (UAV: Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.In addition, the terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, RSU (road side unit), robot, AI (Artificial Intelligence) module, UAV (Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0033] The following technologies can be used in various wireless access systems, such as CDMA, FDMA, TDMA, OFDMA, and SC-FDMA. CDMA can be implemented using wireless technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented using wireless technologies such as GSM (Global System for Mobile communications) / GPRS (General Packet Radio Service) / EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro 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 / LTE-A pro.

[0034] For clarity, the description is based on a 3GPP communication system (e.g., LTE-A, NR), but the technical idea of ​​the present disclosure is not limited thereto. LTE refers to technology after 3GPP TS (Technical Specification) 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR refers to technology after TS 38.xxx Release 15. LTE / NR may be referred to as a 3GPP system. "xxx" refers to a standard document detail number. LTE / NR may be collectively referred to as a 3GPP system. For background technology, terms, abbreviations, etc. used in the description of the present disclosure, reference may be made to matters described in standard documents published prior to the present disclosure. For example, reference may be made to the following documents.

[0035] For 3GPP LTE, see TS 36.211 (Physical channels and modulation), TS 36.212 (Multiplexing and channel coding), TS 36.213 (Physical layer procedures), TS 36.300 (General description), and TS 36.331 (Radio resource control).

[0036] For 3GPP NR, see TS 38.211 (Physical channels and modulation), TS 38.212 (Multiplexing and channel coding), TS 38.213 (Physical layer procedures for control), TS 38.214 (Physical layer procedures for data), TS 38.300 (Overall description of NR and New Generation-Radio Access Network (NG-RAN)), and TS 38.331 (Radio Resource Control Protocol Specification).

[0037] Abbreviations for terms that may be used in this disclosure are defined as follows.

[0038] - BM: beam management

[0039] - CQI: Channel Quality Indicator

[0040] - CRI: Channel state information - reference signal resource indicator

[0041] - CSI: Channel State Information

[0042] - CSI-IM: Channel State Information - Interference Measurement

[0043] - CSI-RS: Channel state information - reference signal

[0044] - DMRS: Demodulation Reference Signal

[0045] - FDM: frequency division multiplexing

[0046] - FFT: fast Fourier transform

[0047] - IFDMA: interleaved frequency division multiple access

[0048] - IFFT: inverse fast Fourier transform

[0049] - L1-RSRP: Layer 1 reference signal received power

[0050] - L1-RSRQ: Layer 1 reference signal received quality

[0051] - MAC: Medium Access Control

[0052] - NZP: non-zero power

[0053] - OFDM: orthogonal frequency division multiplexing

[0054] - PDCCH: Physical downlink control channel

[0055] - PDSCH: Physical downlink shared channel

[0056] - PMI: precoding matrix indicator

[0057] - RE: resource element

[0058] - RI: Rank indicator

[0059] - RRC: Radio Resource Control

[0060] - RSSI: Received signal strength indicator

[0061] - Rx: Reception

[0062] - QCL: quasi co-location

[0063] - SINR: signal to interference and noise ratio

[0064] - SSB (or SS / PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

[0065] - TDM: Time Division Multiplexing

[0066] - TRP: transmission and reception point

[0067] - TRS: Tracking Reference Signal

[0068] - Tx: transmission

[0069] - UE: user equipment

[0070] - ZP: Zero Power

[0071] System General

[0072] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communications compared to existing radio access technologies (RATs) is emerging. Furthermore, massive Machine Type Communications (MTC), which connects numerous devices and objects to provide diverse services anytime, anywhere, is also a key issue to be considered in next-generation communications. Furthermore, communication system design that considers reliability and latency-sensitive services / terminals is being discussed. Accordingly, the introduction of next-generation RATs that consider enhanced mobile broadband communication (eMBB), massive MTC (MMTC), and Ultra-Reliable and Low Latency Communication (URLLC) is being discussed. For convenience, these technologies are referred to as NR in this disclosure. NR is an expression representing an example of 5G RAT.

[0073] A new RAT system, including NR, uses OFDM or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but support a larger system bandwidth (e.g., 100 MHz). Alternatively, a single cell may support multiple numerologies. That is, terminals operating under different numerologies can coexist within a single cell.

[0074] A numerology corresponds to a single subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0075] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0076] Referring to Fig. 1, the NG-RAN consists of gNBs that provide NG-RA (NG-Radio Access) user plane (i.e., new AS (access stratum) sublayer / PDCP (Packet Data Convergence Protocol) / RLC (Radio Link Control) / MAC / PHY) and control plane (RRC) protocol termination for UE. The gNBs are interconnected via Xn interfaces. The gNBs are also connected to the NGC (New Generation Core) via the NG interface. More specifically, the gNBs are connected to the AMF (Access and Mobility Management Function) via the N2 interface and to the UPF (User Plane Function) via the N3 interface.

[0077] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0078] NR systems can support multiple numerologies. Numerologies can be defined by subcarrier spacing and cyclic prefix (CP) overhead. Multiple subcarrier spacings can be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). Furthermore, even if it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used can be selected independently of the frequency band. Furthermore, NR systems can support various frame structures corresponding to multiple numerologies.

[0079] Below, we examine OFDM numerologies and frame structures that can be considered in NR systems. The various OFDM numerologies supported in NR systems can be defined as shown in Table 1 below.

[0080] μΔf=2 μ ·15 [kHz]CP015 Normal 130 Normal 260 Normal, Extended 3120 Normal 4240 Normal

[0081] NR supports multiple numerologies (or subcarrier spacings (SCS)) to support various 5G services. For example, an SCS of 15 kHz supports wide areas in traditional cellular bands; an SCS of 30 kHz / 60 kHz supports dense urban areas, lower latency, and wider carrier bandwidth; and an SCS of 60 kHz or higher supports bandwidths greater than 24.25 GHz to overcome phase noise.

[0082] The NR frequency band is defined by two types of frequency ranges (FR1 and FR2). FR1 and FR2 can be configured as shown in Table 2 below. FR2 can also mean millimeter wave (mmW).

[0083] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1410MHz - 7125MHz 15, 30, 60kHz FR224250MHz - 52600MHz 60, 120, 240kHz

[0084] Regarding the frame structure in the NR system, the sizes of the various fields in the time domain are T c =1 / (Δf max ·N f ) is expressed as a multiple of the time unit. Here, Δf max =480·10 3 Hz and N f =4096. Downlink and uplink transmissions are T f =1 / (Δf max N f / 100)·T c = It is organized into radio frames with a duration of 10ms. Here, each radio frame is T sf =(Δf max N f / 1000)·T c =1ms It consists of 10 subframes with an interval of . In this case, there may be one set of frames for uplink and one set of frames for downlink. In addition, transmission in uplink frame number i from a terminal is T earlier than the start of the corresponding downlink frame from the terminal.TA =(N TA +N TA,offset )T c It should start before. For the subcarrier spacing configuration μ, slots are n within a subframe. s μ ∈{0,..., N slot subframe,μ-1} are numbered in increasing order, and n within a radio frame. s,f μ ∈{0,..., N slot frame,μ -1} are numbered in increasing order. One slot is N symb slot It consists of consecutive OFDM symbols, and N symb slot is determined by CP. Slot n in subframe s μ The start of OFDM symbol n in the same subframe s μ N symb slot are aligned temporally with the start of the OFDM signal. Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be utilized.

[0085] Table 3 shows the number of OFDM symbols per slot in a general CP (N symb slot ), the number of slots per wireless frame (N slot frame,μ ), number of slots per subframe (N slot subframe,μ), and Table 4 shows the number of OFDM symbols per slot in the extended CP, the number of slots per radio frame, and the number of slots per subframe.

[0086] μN symb slot N slot frame,μ N slotsubframe,μ01410111420221440431480841416016

[0087] μN symb slot N slot frame,μ N slot subframe,μ212404

[0088] Fig. 2 is an example when μ=2 (SCS is 60 kHz), and referring to Table 3, 1 subframe can include 4 slots. 1 subframe={1,2,4} slot shown in Fig. 2 is an example, and the number of slot(s) that can be included in 1 subframe is defined as in Table 3 or Table 4. In addition, a mini-slot can include 2, 4, or 7 symbols, or more or fewer symbols.

[0089] Regarding physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered. Below, the physical resources that can be considered in an NR system will be examined in detail.

[0090] First, with respect to antenna ports, antenna ports are defined such that the channel through which a symbol on an antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. Two antenna ports are said to be in a QC / QCL (quasi co-located or quasi co-location) relationship if the large-scale properties of the channel through which a symbol on one antenna port is carried can be inferred from the channel through which a symbol on another antenna port is carried. Here, the large-scale properties include one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

[0091] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0092] Referring to Figure 3, the resource grid is N in the frequency domain. RB μ N sc RB It consists of subcarriers, and one subframe is 14·2 μ It is described as an example, but not limited to, that it consists of OFDM symbols. In an NR system, the transmitted signal is N RB μ N sc RB One or more resource grids consisting of subcarriers and 2 μ N symb (μ) is described by OFDM symbols. Here, N RB μ≤ N RB max,μ is. The above N RB max,μrepresents the maximum transmission bandwidth, which may vary between uplink and downlink as well as between numerologies. In this case, one resource grid may be configured for μ and each antenna port p. Each element of the resource grid for μ and each antenna port p is referred to as a resource element and is uniquely identified by an index pair (k, l'). Here, k=0,...,N RB μ N sc RB -1 is the index in the frequency domain, and l'=0,...,2 μ N symb (μ) -1 indicates the position of the symbol within the subframe. When referring to a resource element in a slot, an index pair (k,l) is used. Here, l=0,...,N symb μ -1. The resource element (k,l') for μ and antenna port p is a complex value a k,l' (p,μ) . If there is no risk of confusion or if a particular antenna port or numerology is not specified, the indices p and μ can be dropped, resulting in a complex value of a k,l' (p) or a k,l' This can be. Also, a resource block (RB) is N in the frequency domain. sc RB =12 is defined as consecutive subcarriers.

[0093] Point A serves as a common reference point of the resource block grid and is obtained as follows.

[0094] - offsetToPointA for the Primary Cell (PCell) downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping the SS / PBCH block used by the UE for initial cell selection. It is expressed in resource block units assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier spacing for FR2.

[0095] - absoluteFrequencyPointA represents the frequency-position of point A expressed as ARFCN (absolute radio-frequency channel number).

[0096] Common resource blocks (CRBs) are numbered from 0 upwards in the frequency domain for a subcarrier spacing setting μ. The center of subcarrier 0 of CRB 0 for a subcarrier spacing setting μ coincides with 'point A'. CRB number n in the frequency domain CRB μ The relationship between the resource elements (k,l) and the subcarrier spacing setting μ is given by the following mathematical expression 1.

[0097]

[0098] In Equation 1, k is defined relative to point A such that k = 0 corresponds to the subcarrier centered at point A. Physical resource blocks are numbered from 0 to N within the bandwidth part (BWP). BWP,i size,μ - Numbered from -1, where i is the number of the BWP. Physical resource block n in BWP i PRB and common resource block n CRB The relationship between them is given by the mathematical formula 2 below.

[0099]

[0100] N BWP,i start,μ is a common resource block where BWP starts relative to common resource block 0.

[0101] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied. FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0102] Referring to FIGS. 4 and 5, a slot includes multiple symbols in the time domain. For example, in the case of a normal CP, one slot includes seven symbols, but in the case of an extended CP, one slot includes six symbols.

[0103] A carrier comprises multiple subcarriers in the frequency domain. An RB (Resource Block) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A BWP (Bandwidth Part) is defined as multiple consecutive (physical) resource blocks in the frequency domain, and can correspond to a single numerology (e.g., SCS, CP length, etc.). A carrier can comprise up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for a single terminal. Each element in the resource grid is referred to as a Resource Element (RE), to which one complex symbol can be mapped.

[0104] The NR system can support up to 400 MHz per component carrier (CC). If a terminal operating in such a wideband CC always operates with the radio frequency (RF) chip for the entire CC turned on, the terminal battery consumption may increase. Alternatively, when considering multiple use cases operating within a single wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.), different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band within the CC. Alternatively, each terminal may have different maximum bandwidth capabilities. Considering this, the base station can instruct the terminal to operate only on a portion of the bandwidth rather than the entire bandwidth of the wideband CC, and this portion of bandwidth is conveniently defined as the bandwidth part (BWP). A BWP can be composed of consecutive RBs on the frequency axis and can correspond to a single numerology (e.g., subcarrier spacing, CP length, slot / mini-slot interval).

[0105] Meanwhile, the base station can configure multiple BWPs even within a single CC configured for a terminal. For example, in the PDCCH monitoring slot, a BWP occupying a relatively small frequency range can be configured, and the PDSCH indicated by the PDCCH can be scheduled on a larger BWP. Alternatively, if UEs are concentrated on a specific BWP, some terminals can be configured to a different BWP for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, a portion of the spectrum in the middle of the entire bandwidth can be excluded and both BWPs can be configured within the same slot. In other words, the base station can configure at least one DL / UL BWP for a terminal associated with a wideband CC. The base station can activate at least one DL / UL BWP(s) among the configured DL / UL BWP(s) at a specific time (via L1 signaling, MAC CE (Control Element), RRC signaling, etc.). Additionally, the base station can instruct switching to another configured DL / UL BWP (e.g., via L1 signaling or MAC CE or RRC signaling). Alternatively, switching to a configured DL / UL BWP can be performed based on a timer when the timer value expires. In this case, the activated DL / UL BWP is defined as the active DL / UL BWP. However, in situations such as when the terminal is performing the initial access process or before the RRC connection is set up, the configuration for the DL / UL BWP may not be received. Therefore, in these situations, the DL / UL BWP assumed by the terminal is defined as the initially active DL / UL BWP.

[0106] FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

[0107] In wireless communication systems, terminals receive information from a base station via the downlink and transmit it to the base station via the uplink. The information transmitted and received between the base station and terminals includes data and various control information, and various physical channels exist depending on the type and purpose of the information being transmitted and received.

[0108] When a terminal is powered on or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station (S601). To this end, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell identifier (ID). Afterwards, the terminal can receive a physical broadcast channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a downlink reference signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0109] A terminal that has completed initial cell search can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information carried on the PDCCH (S602).

[0110] Meanwhile, when accessing a base station for the first time or when there are no radio resources for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (steps S603 to S606). To this end, the terminal may transmit a specific sequence as a preamble via the Physical Random Access Channel (PRACH) (steps S603 and S605) and receive a response message to the preamble via the Physical Data Channel Control Channel (PDCCH) and the corresponding PDSCH (steps S604 and S606). In the case of a contention-based RACH, a contention resolution procedure (Contention Resolution Procedure) may additionally be performed.

[0111] The terminal that has performed the procedure described above can then perform PDCCH / PDSCH reception (S607) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S608) as general uplink / downlink signal transmission procedures. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, DCI includes control information such as resource allocation information for the terminal, and its format varies depending on the purpose of use.

[0112] Meanwhile, the control information that the terminal transmits to the base station via the uplink or that the terminal receives from the base station includes downlink / uplink ACK / NACK (Acknowledgement / Non-Acknowledgement) signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator), etc. In the case of the 3GPP LTE system, the terminal can transmit the above-described control information such as CQI / PMI / RI via PUSCH and / or PUCCH.

[0113] Table 5 shows an example of the DCI format in the NR system.

[0114] DCI Format Utilization 0_0 Scheduling of PUSCH within a cell 0_1 Scheduling of one or multiple PUSCH within a cell, or indicating cell group (CG: cell group) downlink feedback information to the UE 0_2 Scheduling of PUSCH within a cell 1_0 Scheduling of PDSCH within a DL cell 1_1 Scheduling of PDSCH within a cell 1_2 Scheduling of PDSCH within a cell

[0115] Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information related to scheduling of PUSCH (e.g., UL / SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), transport block (TB) related information (e.g., MCS (Modulation Coding and Scheme), NDI (New Data Indicator), RV (Redundancy Version), etc.), HARQ (Hybrid - Automatic Repeat and request) related information (e.g., process number, DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., DMRS sequence initialization information, antenna port, CSI request, etc.), power control information (e.g., PUSCH power control, etc.), and the control information included in each DCI format may be predefined.

[0116] DCI format 0_0 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_0 is transmitted after being scrambled with a CRC (cyclic redundancy check) by a C-RNTI (Cell RNTI: Cell Radio Network Temporary Identifier), a CS-RNTI (Configured Scheduling RNTI), or a MCS-C-RNTI (Modulation Coding Scheme Cell RNTI).

[0117] DCI format 0_1 ​​is used to indicate scheduling of one or more PUSCHs in a single cell, or configure grant (CG: configure grant) downlink feedback information to the UE. The information contained in DCI format 0_1 ​​is CRC-scrambled and transmitted using the C-RNTI, CS-RNTI, SP-CSI-RNTI (Semi-Persistent CSI RNTI), or MCS-C-RNTI.

[0118] DCI format 0_2 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, SP-CSI-RNTI, or MCS-C-RNTI.

[0119] Next, DCI formats 1_0, 1_1, and 1_2 may include resource information related to scheduling of PDSCH (e.g., frequency resource allocation, time resource allocation, virtual resource block (VRB)-physical resource block (PRB) mapping, etc.), transport block (TB) related information (e.g., MCS, NDI, RV, etc.), HARQ related information (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., antenna port, transmission configuration indicator (TCI), sounding reference signal (SRS) request, etc.), PUCCH related information (e.g., PUCCH power control, PUCCH resource indicator, etc.), and control information included in each DCI format may be predefined.

[0120] DCI format 1_0 is used for scheduling PDSCH in a DL cell. The information contained in DCI format 1_0 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0121] DCI format 1_1 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_1 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0122] DCI format 1_2 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0123] Timing advance (TA) related operations

[0124] FIG. 7 is a diagram illustrating an uplink-downlink timing relationship in a wireless communication system to which the present disclosure can be applied.

[0125] The uplink frame number i for transmission from the UE is T before the start of the corresponding downlink frame (i.e., downlink frame i) in the UE. TA =(N TA +N TA,offset )T c starts as much earlier than the corresponding downlink frame. That is, the uplink frame is T TA It starts as early as N. Here, N TA,offset Sends msgA on PUCH (in this case, N TA =0) is given in TS 38.213.

[0126] Below, N TA Describes how to set up .

[0127] N TAcan be set via i) a random access response (RAR) or ii) a timing advance command MAC control element (CE).

[0128] Case 1: How to set up via RAR

[0129] For random access response or absolute timing advance command MAC CE (T) for timing advance group (TAG) A ) the timing advance command is T A N with index values ​​of =0, 2, ..., 3846 TA Indicates the values. Here, 2 μ ·The amount of time alignment for a TAG with an SCS of 15 kHz is N TA =T A ·16·64 / 2 μ am. N TA is relative to the SCS of the first uplink transmission from the UE after receipt of a random access response or absolute timing advance command MAC CE.

[0130] FIG. 8 illustrates a MAC CE for a random access response in a wireless communication system to which the present disclosure can be applied.

[0131] The MAC CE (hereinafter, MAC RAR) for random access response has a fixed size as shown in Fig. 8 and includes the following fields.

[0132] - R: Reserved bit, set to 0;

[0133] - Timing Advance Command: The Timing Advance Command field is an index value T used to control the amount of timing adjustment that the MAC entity should apply. A The size of the Timing Advance Command field is 12 bits.

[0134] - UL Grant: The Uplink Grant field indicates the resources to be used for the uplink. The UL Grant field is 27 bits in size.

[0135] - Temporary C-RNTI: The Temporary C-RNTI field is a temporary identity used by the MAC entity during random access. The size of the Temporary C-RNTI field is 16 bits.

[0136] Case 2: How to set via Timing advance command (MAC-CE)

[0137] Timing advance command for TAG (T A ) is T A =0,1,2,...,63 as index values ​​for the current N TA value (i.e. N TA_old )'s new N TA value (i.e. N TA_new ) indicates an adjustment. Here, 2 μ ·N for 15 kHz SCS TA_new =N TA_old +(T A -31)·16·64 / 2 μ am.

[0138] FIG. 9 illustrates a timing advance command MAC CE in a wireless communication system to which the present disclosure can be applied.

[0139] The Timing Advance Command MAC CE is identified by a MAC subheader containing a logical channel identity (LCID). The Timing Advance Command MAC CE has a fixed size and consists of one octet as follows:

[0140] - TAG Identifier (TAG ID: TAG Identity): This field indicates the TAG identifier of the addressed TAG. A TAG containing SpCell has TAG identifier 0. The length of this field is 2 bits.

[0141] - Timing Advance Command: This field is an index value T used to control the amount of timing adjustment that the MAC entity should apply. A The length of the Timing Advance Command field is 6 bits.

[0142] Although the present disclosure primarily exemplifies and describes a 4-step random access procedure (i.e., RACH procedure), the present disclosure does not exclude a 2-step random access procedure, and thus the present disclosure can be equally applied to a 2-step random access procedure.

[0143] Below, N TA,offset Describes how to set up .

[0144] Case 1: How to set specific values ​​for each serving cell

[0145] An information element (IE) for common configuration of a serving cell (e.g., ServingCellConfigCommon) is used to configure cell-specific parameters of a UE's serving cell. When a UE accesses a cell from an idle state, the IE contains parameters that can typically be obtained from an SSB, a master information block (MIB), or a SIB. Along with this IE, the network provides information in dedicated signaling when configuring secondary cells (SCells) or additional cell groups (SCGs) to the UE. The network also provides the UE with information about special cells (SpCells) (master cell group (MCG) and SCG) when re-establishing synchronization.

[0146] Table 6 illustrates the ServingCellConfigCommon IE.

[0147] ServingCellConfigCommon ::= SEQUENCE {physCellId PhysCellId OPTIONAL, -- Cond HOAndServCellAdd,downlinkConfigCommon DownlinkConfigCommon OPTIONAL, -- Cond HOAndServCellAdduplinkConfigCommon UplinkConfigCommon OPTIONAL, -- Need MsupplementaryUplinkConfig UplinkConfigCommon OPTIONAL, -- Need Sn-TimingAdvanceOffset ENUMERATED { n0, n25600, n39936} OPTIONAL, -- Need Sssb-PositionsInBurst CHOICE {shortBitmap BIT STRING (SIZE (4)),mediumBitmap BIT STRING (SIZE (8)),longBitmap BIT STRING (SIZE (64))} OPTIONAL, -- Cond AbsFreqSSBssb-periodicityServingCell ENUMERATED { ms5, ms10, ms20, ms40, ms80, ms160, spare2, spare1} OPTIONAL, -- Need Sdmrs-TypeA-Position ENUMERATED {pos2, pos3},lte-CRS-ToMatchAround SetupRelease { RateMatchPatternLTE-CRS} OPTIONAL, -- Need MrateMatchPatternToAddModList SEQUENCE (SIZE (1..maxNrofRateMatchPatterns)) OF RateMatchPattern OPTIONAL, -- Need NrateMatchPatternToReleaseList SEQUENCE (SIZE (1..maxNrofRateMatchPatterns)) OF RateMatchPatternId OPTIONAL,-- Need NssbSubcarrierSpacing SubcarrierSpacing OPTIONAL, -- Cond HOAndServCellWithSSBtdd-UL-DL-ConfigurationCommon TDD-UL-DL-ConfigCommon OPTIONAL, -- Cond TDDss-PBCH-BlockPower INTEGER (-60..50),...,[[channelAccessMode-r16 CHOICE {dynamic NULL,semiStatic SemiStaticChannelAccessConfig-r16} OPTIONAL, -- Cond SharedSpectrumdiscoveryBurstWindowLength-r16 ENUMERATED {ms0dot5, ms1, ms2, ms3, ms4, ms5} OPTIONAL, -- Need Rssb-PositionQCL-r16 SSB-PositionQCL-Relation-r16 OPTIONAL, -- Cond SharedSpectrumhighSpeedConfig-r16 HighSpeedConfig-r16 OPTIONAL -- Need R]],[[highSpeedConfig-v1700 HighSpeedConfig-v1700 OPTIONAL, -- Need RchannelAccessMode2-r17 ENUMERATED {enabled} OPTIONAL, -- Cond SharedSpectrum2discoveryBurstWindowLength-r17 ENUMERATED {ms0dot125, ms0dot25, ms0dot5, ms0dot75, ms1, ms1dot25} OPTIONAL, -- Need Rssb-PositionQCL-r17 SSB-PositionQCL-Relation-r17 OPTIONAL, -- Cond SharedSpectrum2highSpeedConfigFR2-r17 HighSpeedConfigFR2-r17 OPTIONAL,-- Need RuplinkConfigCommon-v1700 UplinkConfigCommon-v1700 OPTIONAL, -- Need Rntn-Config-r17 NTN-Config-r17 OPTIONAL -- Need R]],[[featurePriorities-r17 SEQUENCE {redCapPriority-r17 FeaturePriority-r17 OPTIONAL, -- Need RslicingPriority-r17 FeaturePriority-r17 OPTIONAL, -- Need Rmsg3-Repetitions-Priority-r17 FeaturePriority-r17 OPTIONAL, -- Need Rsdt-Priority-r17 FeaturePriority-r17 OPTIONAL -- Need R} OPTIONAL -- Need R]]},

[0148] Referring to Table 6, the n-TimingAdvanceOffset field (or parameter) specifies the N that will be applied to all uplink transmissions on the serving cell. TA,offset If this field does not exist, the UE applies the values ​​defined for the duplex mode and frequency range (FR) of the serving cell.

[0149] Case 2: How to apply predefined values ​​to the serving cell according to the duplex mode and frequency range (FR).

[0150] Table 7 shows N TA,offset exemplifies the value of .

[0151]

[0152] Referring to Table 7, N is determined based on the frequency range (FR) and band of the cell used for uplink transmission. TA,offsetThe value of is determined. If it is neither an E-UTRA-NR coexistence nor an NB-IoT-NR coexistence case and it is an FR1 FDD or TDD band, N TA,offset The value is 25600. In case of FR1 FDD band in E-UTRA-NR and / or NB-IoT-NR coexistence case, N TA,offset The value is 0. In case of FR1 TDD band in E-UTRA-NR and / or NB-IoT-NR coexistence case, N TA,offset The value of is 39936. If FR2, N TA,offset The value is 13792.

[0153] As described above, the UE determines N based on the n-TimingAdvanceOffset field (or parameter) information. TA,offset Identifies the value of N. However, if the UE is not provided with n-TimingAdvanceOffset field (or parameter) information, N TA,offset The default value is set to 25600 for the FR1 band. For multiple UL carriers within the same timing advance group (TAG), the UE expects the same n-TimingAdvanceOffset value for all UL carriers, and N TA,offset A value of 39936 may also be provided for the FDD serving cell.

[0154] Below, the timing advance group (TAG) is described.

[0155] For cells configured by RRC and also configured with UL, TAG refers to a group of serving cells that use the same timing reference cell and the same timing advance value. The TAG that contains the SpCell of the MAC entity is called the Primary Timing Advance Group (PTAG), while the Secondary Timing Advance Group (STAG) refers to other TAGs.

[0156] An IE for TAG configuration (e.g. TAG-Config) is used to set parameters for a time-alignment group.

[0157] Table 8 illustrates the TAG-Config IE.

[0158] TAG-Config ::= SEQUENCE {tag-ToReleaseList SEQUENCE (SIZE (1..maxNrofTAGs)) OF TAG-Id OPTIONAL, -- Need Ntag-ToAddModList SEQUENCE (SIZE (1..maxNrofTAGs)) OF TAG OPTIONAL -- Need N}TAG ::= SEQUENCE {tag-Id TAG-Id,timeAlignmentTimer TimeAlignmentTimer,...}TAG-Id ::= INTEGER (0..maxNrofTAGs-1)

[0159] Referring to Table 8, the tag-Id field (parameter) indicates the TAG of an SpCell or SCell. This field uniquely identifies the TAG within the scope of a cell group.

[0160] Additionally, the timeAlignmentTimer field (parameter) indicates the time alignment timer value (in [ms]) for the TAG with tag-Id.

[0161] The maximum number of TAGs can be determined by the standard or by the base station, for example it can be 4.

[0162] An IE for MAC cell group configuration (e.g., MAC-CellGroupConfig) is used to configure MAC parameters for a cell group, including discontinuous reception (DRX).

[0163] Table 9 illustrates a portion of the MAC-CellGroupConfig IE.

[0164] MAC-CellGroupConfig ::= SEQUENCE {drx-Config SetupRelease { DRX-Config} OPTIONAL, -- Need MschedulingRequestConfig SchedulingRequestConfig OPTIONAL, -- Need Mbsr-Config BSR-Config OPTIONAL, -- Need Mtag-Config TAG-Config OPTIONAL, -- Need Mphr-Config SetupRelease { PHR-Config} OPTIONAL, -- Need MskipUplinkTxDynamic BOOLEAN,...,[[csi-Mask BOOLEAN OPTIONAL, -- Need MdataInactivityTimer SetupRelease { DataInactivityTimer} OPTIONAL -- Cond MCG-Only]],[[usePreBSR-r16 ENUMERATED {true} OPTIONAL, -- Need RschedulingRequestID-LBT-SCell-r16 SchedulingRequestId OPTIONAL, -- Need Rlch-BasedPrioritization-r16 ENUMERATED {enabled} OPTIONAL, -- Need RschedulingRequestID-BFR-SCell-r16 SchedulingRequestId OPTIONAL, -- Need Rdrx-ConfigSecondaryGroup-r16 SetupRelease { DRX-ConfigSecondaryGroup-r16} OPTIONAL -- Need M]],[[enhancedSkipUplinkTxDynamic-r16 ENUMERATED {true} OPTIONAL, -- Need RenhancedSkipUplinkTxConfigured-r16 ENUMERATED {true} OPTIONAL -- Need R]],[[intraCG-Prioritization-r17 ENUMERATED {enabled} OPTIONAL, -- Cond LCH-PrioWithReTxTimerdrx-ConfigSL-r17 SetupRelease { DRX-ConfigSL-r17} OPTIONAL, -- Need Mdrx-ConfigExt-v1700 SetupRelease { DRX-ConfigExt-v1700} OPTIONAL, -- Need MschedulingRequestID-BFR-r17 SchedulingRequestId OPTIONAL, -- Need RschedulingRequestID-BFR2-r17 SchedulingRequestId OPTIONAL, -- Need RschedulingRequestConfig-v1700 SchedulingRequestConfig-v1700 OPTIONAL, -- Need Mtar-Config-r17 SetupRelease { TAR-Config-r17} OPTIONAL, -- Need Mg-RNTI-ConfigToAddModList-r17 SEQUENCE (SIZE (1..maxG-RNTI-r17)) OF MBS-RNTI-SpecificConfig-r17 OPTIONAL, -- Need Ng-RNTI-ConfigToReleaseList-r17 SEQUENCE (SIZE (1..maxG-RNTI-r17)) OF MBS-RNTI-SpecificConfigId-r17 OPTIONAL, -- Need Ng-CS-RNTI-ConfigToAddModList-r17 SEQUENCE (SIZE (1..maxG-CS-RNTI-r17)) OF MBS-RNTI-SpecificConfig-r17 OPTIONAL, -- Need Ng-CS-RNTI-ConfigToReleaseList-r17 SEQUENCE (SIZE (1..maxG-CS-RNTI-r17)) OF MBS-RNTI-SpecificConfigId-r17 OPTIONAL,-- Need NallowCSI-SRS-Tx-MulticastDRX-Active-r17 BOOLEAN OPTIONAL -- Need M]],[[schedulingRequestID-PosMG-Request-r17 SchedulingRequestId OPTIONAL, -- Need Rdrx-LastTransmissionUL-r17 ENUMERATED {enabled} OPTIONAL -- Need R]]},

[0165] Referring to Table 9, the TAG-Config IE can be set through the tag-Config field in the MAC-CellGroupConfig IE.

[0166] An IE for cell group configuration (e.g., CellGroupConfig) is used to configure a master cell group (MCG) or a secondary cell group (SCG). A cell group is associated with one MAC entity and Radio Link Control (RLC) entities and includes a set of logical channels of a primary cell (SpCell) and one or more secondary cells (SCells).

[0167] Table 10 illustrates part of the CellGroupConfig IE.

[0168] CellGroupConfig ::= SEQUENCE {cellGroupId CellGroupId,rlc-BearerToAddModList SEQUENCE (SIZE(1..maxLC-ID)) OF RLC-BearerConfig OPTIONAL, -- Need Nrlc-BearerToReleaseList SEQUENCE (SIZE(1..maxLC-ID)) OF LogicalChannelIdentity OPTIONAL, -- Need Nmac-CellGroupConfig MAC-CellGroupConfig OPTIONAL, -- Need MphysicalCellGroupConfig PhysicalCellGroupConfig OPTIONAL, -- Need MspCellConfig SpCellConfig OPTIONAL, -- Need MsCellToAddModList SEQUENCE (SIZE (1..maxNrofSCells)) OF SCellConfig OPTIONAL, -- Need NsCellToReleaseList SEQUENCE (SIZE (1..maxNrofSCells)) OF SCellIndex OPTIONAL, -- Need N...,

[0169] Referring to Table 10, the MAC-CellGroupConfig IE can be set via the mac-CellGroupConfig field in the CellGroupConfig IE.

[0170] The maximum number of secondary cell groups may be determined by the standard or by the base station, and may be, for example, 3.

[0171] Table 11 illustrates the operation of the MAC entity for maintenance of uplink time alignment.

[0172] 5.2 Maintenance of uplink time alignment The RRC sets the following parameters for the maintenance of UL time alignment: - timeAlignmentTimer (per TAG) that controls the period of time for which the serving cell belonging to the TAG to which the MAC entity is associated considers the uplink time aligned. The MAC entity: 1> When a Timing Advance Command MAC CE is received, and N for the indicated TAG TAWhen: 2> Apply Timing Advance Command for the indicated TAG; 2> Start or restart the timeAlignmentTimer associated with the indicated TAG. 1> When Timing Advance Command is received in Random Access Response message for a serving cell belonging to the TAG or in message B (MSGB) for SpCell: 2> If a random access preamble is not selected by the MAC entity among contention-based random access preambles: 3> Apply Timing Advance Command for this TAG; 3> Start or restart the timeAlignmentTimer associated with this TAG. 2> Otherwise, if the timeAlignmentTimer associated with this TAG is not running: 3> Apply Timing Advance Command for this TAG; 3> Start or restart the timeAlignmentTimer associated with this TAG; 3> When contention resolution is not considered successful; or 3> After transmitting HARQ feedback for a MAC protocol data unit (PDU) containing a UE Contention Resolution Identity (MAC CE), when contention resolution is considered successful for a system information (SI) request: 4> Stop the timeAlignmentTimer associated with this TAG. 2> Otherwise: 3> Ignore the received Timing Advance Command.1> When an Absolute Timing Advance Command is received in response to a message A (MSGA) containing a C-RNTI MAC CE: 2> Apply the Timing Advance Command to the PTAG; 2> Start or restart the timeAlignmentTimer associated with the PTAG; 1> When a timeAlignmentTimer expires: 2> If a timeAlignmentTimer is associated with the PTAG: 3> Flush all HARQ buffers for all serving cells; 3> If set, notify RRC to release PUCCH for all serving cells; 3> If set, notify RRC to release SRS for all serving cells; 3> Clear configured downlink assignments and configured uplink grants; 3> Clear PUSCH resource for semi-persistent CSI reporting; 3> Mark all running timeAlignmentTimers as expired. Consider;3> N for all TAGs. TA 2> Otherwise, if timeAlignmentTimer is associated with a STAG, for all serving cells belonging to this TAG: 3> Flush all HARQ buffers; 3> If configured, notify RRC to release PUCCH; 3> If configured, notify RRC to release SRS; 3> Clear configured downlink assignments and configured uplink grants; 3> Clear PUSCH resource for semi-persistent CSI reporting; 3> N of this TAG TAIf the MAC entity stops uplink transmission for a SCell due to exceeding the maximum uplink transmission timing difference between the TAGs of the MAC entity or the maximum uplink transmission timing difference between the TAGs of any MAC entity of the UE, the MAC entity considers the timeAlignmentTimer associated with the SCell to have expired. When the timeAlignmentTimer associated with the TAG to which the serving cell belongs is not running, the MAC entity does not perform any uplink transmission on that serving cell except for random access preamble and MSGA transmissions. Furthermore, when the timeAlignmentTimer associated with a PTAG is not running, the MAC entity does not perform any uplink transmission on any serving cell except for random access preamble and MSGA transmissions on SpCell.

[0173] Uplink transmission to uplink receiving point

[0174] In existing wireless communication systems, the operations of uplink transmission and downlink reception of terminals based on multiple TRPs (M-TRPs) and uplink reception and downlink transmission of base stations are defined. These M-TRP operations may include single-DCI (S-DCI)-based M-TRP operations in which a specific TRP transmits a control signal to the terminal, and multi-DCI (M-DCI)-based M-TRP operations in which multiple TRPs all transmit control signals to the terminal. In improved wireless communication systems, one or more uplink reception points (or uplink reception-only points, hereinafter referred to as UL Rx points) additionally deployed in a macro cell are being discussed for uplink coverage compensation of terminals.

[0175] In order to reduce base station installation costs, this UL Rx point can be implemented to perform only UL reception without a DL transmission chain. In this case, since the UL Rx point cannot transmit a DL reference signal (RS), the UE cannot know the DL slot boundary (or reference point) for applying TA to the UL Rx point. In addition, since the UL Rx point does not transmit SSB, the existing SSB-based RACH procedure cannot be applied as is to the RACH procedure for acquiring TA related to the timing of UL transmission to the UL Rx point of the UE. In addition, in the existing wireless communication system, a pathloss reference RS (hereinafter, PL-RS) is set as an open-loop parameter for UL power control, but since the UL Rx point does not perform DL transmission, the DL RS to be used as the PL-RS cannot be set for the UE. Furthermore, even if the terminal has the capability for beam correspondence, for a UL Rx point that does not transmit a DL RS, the DL RS cannot be set as a reference RS for the UL transmission beam of the terminal, so there is a problem that the optimal UL transmission beam for the UL Rx point must be found through the UL beam management operation of the terminal.

[0176] Hereinafter, various examples of the present disclosure are described of a method for a base station to schedule uplink transmission to a terminal and a method for a terminal to acquire and apply TA when the terminal performs uplink transmission for multiple Rx points (e.g., a macro cell and / or an UL Rx point) in a specific CC / BWP(s).

[0177] In the present disclosure, defining information / values ​​may mean that the base station and the terminal know the information / values ​​in advance without signaling / instruction between the base station and the terminal regarding the information. In the present disclosure, setting information / values ​​to the terminal may mean that the base station provides the information / values ​​to the terminal through upper layer (e.g., L3) signaling. In the present disclosure, indicating information / values ​​to the terminal may mean that the base station provides the information / values ​​to the terminal through L2 / L1 signaling such as MAC CE or DCI.

[0178] In addition, the scope of the present disclosure is not limited by the terms macro cell and UL Rx point in the following description. For example, in the present disclosure, a macro cell is used as a term representing a base station or cell that supports both DL and UL transmission / reception, and a UL Rx point (or Rx-only point, or UL TRP) may be used as a term representing a base station or cell that supports only UL reception. For example, a UL Rx point may correspond to a radio remote head (RRH), or functionally, a macro cell may correspond to a central unit (CU) and a distributed unit (DU), or a DU may correspond and the UL Rx point may correspond to a radio unit (RU). In addition, it can be assumed that the macro cell and the UL Rx point are connected by an ideal backhaul so that there is almost no delay in information exchange between the two.

[0179] FIG. 10 is a diagram illustrating the operation of a terminal according to one embodiment of the present disclosure.

[0180] In step S1010, the terminal may receive first information related to the SSB of the first network node and / or the RS of the first network node from the first network node.

[0181] In step S1020, the terminal may transmit a random access preamble to the second network node based on the first information.

[0182] The downlink reference timing or pathloss offset for the random access preamble transmission may be determined by the terminal based on one or more of the SSB or RS of the first information. For example, the transmission beam and / or PL-RS of the random access preamble (or PRACH) may be determined based on the SSB / RS of the first information.

[0183] This first information may be included in a PDCCH order from the first network node to the terminal. Alternatively, the first information may be provided in advance from the first network node to the terminal via uplink signaling or MAC CE before the terminal receives the PDCCH order related to the random access procedure.

[0184] For example, the first network node may correspond to a macro cell or TRP (i.e., a network node that supports both DL transmission and UL reception), and the second network node may correspond to a UL Rx point (i.e., a network node that supports UL reception but does not support DL transmission).

[0185] In step S1030, the terminal may receive a random access response (RAR) in response to the random access preamble from the first network node.

[0186] The RAR may include second information related to timing advance (TA) for a second network node.

[0187] The quasi co-location (QCL) assumption for the PDSCH carrying the RAR and / or the PDCCH scheduling the PDSCH may be based on the SSB of the first information provided by the first network. Alternatively, the QCL assumption for the PDSCH carrying the RAR and / or the PDCCH scheduling the PDSCH may be based on the RS of the first information and / or based on QCL information configured for a control resource set (CORESET) associated with a type-1 common search space (CSS) for the first network node.

[0188] A random access-RNTI (RA-RNTI) related to monitoring of a PDCCH (or DCI including scheduling information for the PDSCH) that schedules a PDSCH carrying an RAR may be calculated based on one or more of a symbol index, a slot index, or a frequency domain index of a PRACH opportunity (occasion) or a RACH opportunity (RO) based on an SSB of the first information.

[0189] Additionally or alternatively, after acquiring TA for the second network node, for the reference point (or radio frame boundary) to which the corresponding TA value is to be applied: the terminal may expect the DL reference point for the first network node to be the same; or a difference value (or offset) of the reference point of the second network node compared to the DL reference point of the first network node may be defined / set / instructed to the terminal; or the value of the N_TA_offset parameter may be defined / set / instructed separately for the second network node (i.e., additionally to the value of the corresponding parameter for the first network node).

[0190] Additionally or alternatively, SRS resource set(s) / SRS resource(s) for the second network node may be separately configured (e.g., in addition to the SRS resource set(s) / SRS resource(s) for the first network node). Based on this, for TA correction for the second network node, a TA command (TAC) corresponding to an absolute value or a TAC corresponding to a relative value may be instructed to the terminal via MAC CE.

[0191] After acquiring a TA for the second network node in this way, the terminal can perform uplink transmission to the second network node based on the acquired TA.

[0192] The TA acquisition operation of the terminal for the second network node as described above may be performed after (i.e., based on) the settings related to the second network node are provided to the terminal (from the first network node). For example, the settings related to the second network node may include information related to the TA settings described above, and / or may include settings related to transmission and reception operations between the first and second network nodes and the terminal (after TA acquisition for the second network node).

[0193] For example, distinct time resources and / or frequency resources may be allocated for the first network node and the second network node. Additionally or alternatively, UL channel / signal resources may be separately configured for the first network node and the second network node. Additionally or alternatively, power control parameters / TA parameters / beam-related parameters may be separately configured for the first network node and the second network node. Additionally or alternatively, different CORESET full indices may be configured for the first network node and the second network node, in which case the terminal may only perform UL transmission for the CORESET full index corresponding to the second network node. Additionally or alternatively, SRS resource sets may be separately configured for the first network node and the second network node. Additionally or alternatively, joint / individual TCI states may be separately configured for the first network node and the second network node. Additionally or alternatively, for the first network node and the second network node, HARQ process IDs may be set separately, and power control parameters / TA parameters / beam-related parameters may be set for each HARQ process ID.

[0194] For example, a first TAG associated with a first network node and a second TAG associated with a second network node may be configured for the terminal. In this case, the second information associated with the TA included in the RAR of step S1030 may be applied to the second TAG. In addition, a first TCI state for the first TAG and a second TCI state for the second TAG may be configured / instructed to the terminal. In this case, uplink transmission from the terminal to the second network node may be performed based on the second TCI state. As an additional example of the above examples, a path loss offset (or reference point) associated with the second TCI state may also be applied to random access preamble transmission to the second network node.

[0195] The method described in the example of FIG. 10 may be performed by the first wireless device (100) of FIG. 12, which will be described later. For example, one or more processors (102) of the first wireless device (100) of FIG. 12 may be configured to receive, by a terminal, from the first network node through one or more transceivers (106) first information related to one or more of the SSB of the first network node or the RS of the first network node; transmit, by the terminal, a random access preamble based on the first information to a second network node through one or more transceivers (106); and receive, by the terminal, from the first network node through one or more transceivers (106) an RAR in response to the random access preamble. The RAR may include second information related to a TA for the second network node. Furthermore, one or more memories (104) of the first wireless device (100) may store instructions for performing the method described in the example of FIG. 10 or the examples described below when executed by one or more processors (102).

[0196] FIG. 11 is a diagram illustrating the operation of a base station according to one embodiment of the present disclosure.

[0197] In step S1110, the first network node may transmit first information related to the SSB of the first network node and / or the RS of the first network node to the terminal.

[0198] In step S1120, the first network node can transmit, to the terminal, an RAR in response to a random access preamble transmitted by the terminal to the second network node based on the first information.

[0199] For example, the connection between a first network node and a second network node may assume an ideal backhaul (i.e., virtually no delay in information exchange between the two). Accordingly, the first network node may assume that the second network node can, without delay, detect that the second network node has received a random access preamble from the terminal. For example, if the second network node receives a random access preamble from the terminal, it may notify the first network node of this.

[0200] The specific features of the first information, second information, random access preamble, and RAR are the same as those described with reference to the example of Fig. 10, so redundant descriptions are omitted.

[0201] The method described in the example of FIG. 11 may be performed by the second wireless device (200) of FIG. 12, which will be described later. For example, one or more processors (202) of the second wireless device (200) of FIG. 12 may be configured to transmit first information related to one or more of the SSB of the first network node or the RS of the first network node to the terminal via one or more transceivers (206) by the first network node; and to transmit, by the first network node, an RAR, in response to a random access preamble transmitted by the terminal to the second network node based on the first information, to the terminal via one or more transceivers (206). The RAR may include second information related to a TA for the second network node. Furthermore, one or more memories (204) of the second wireless device (200) may store instructions for performing the method described in the example of FIG. 11 or the examples described below when executed by one or more processors (202).

[0202] Below, various examples of operation methods for a macro cell and a UL Rx point according to the present disclosure and a method for acquiring TA of a terminal for a UL Rx point are described.

[0203] Example 1

[0204] This embodiment relates to the operation of a macro cell (e.g., a first network node) and a UL Rx point (e.g., a second network node) and an operation method of a terminal.

[0205] The UL Rx point between base station terminals can be operated or managed based on one or more of the following embodiments 1-1 to 1-4.

[0206] Example 1-1

[0207] Different frequency domain resources and / or time domain resources may be allocated for the macro cell and the UL Rx point.

[0208] Example 1-1-1

[0209] The base station can allocate macro cell uplink and UL Rx point uplink to different frequency resources.

[0210] For example, a base station can configure the macro cell uplink and the UL Rx point uplink for the same UL BWP and allocate independent (or different) frequency resources within the UL BWP. In the following description, independent or separate means that they are distinct, but may be the same or different.

[0211] Alternatively, the base station can configure the macro cell uplink and the UL Rx point uplink for different UL BWPs. That is, power control, timing advance, uplink beam-related parameters / resources, etc. can be configured independently (or differently) for different UL BWPs.

[0212] Additionally or alternatively, the base station may utilize a specific supplementary UL (SUL) carrier for the UL Rx point uplink.

[0213] Accordingly, for uplink transmission to a UL Rx point physically located different from the macro cell, power control, timing advance, uplink beam-related parameters / resources, etc. can be separately set / managed.

[0214] Example 1-1-2

[0215] The base station can allocate macro cell uplink and UL Rx point uplink to different time resources.

[0216] For example, in a pattern of downlink / uplink / flexible slot configuration set through upper layer signals TDD-UL-DL-ConfigCommon or / and TDD-UL-DL-ConfigDedicated, information indicating that certain slots among uplink slots (and / or flexible slots) are utilized for a macro cell and the remaining slots are utilized for UL Rx points can be transmitted to the terminal through upper layer signals (e.g., RRC or MAC CE). TDD-UL-DL-ConfigCommon or / and TDD-UL-DL-ConfigDedicated can be utilized to transmit this information.

[0217] Accordingly, depending on which time resource the base station allocates as uplink resource to which target (i.e., depending on whether the uplink resource is allocated to the macro cell or the UL Rx point), the terminal can perform uplink transmission based on different power control, timing advance, uplink beam-related parameters, etc. for the distinct uplink resources.

[0218] Example 1-2

[0219] The base station may separately set the UL channel / signal for the macro cell and the UL channel / signal for the UL Rx point in configuring each UL channel / signal (e.g., including PRACH, PUCCH, PUSCH, and / or SRS), or may independently (or differently) set {power control, timing advance, uplink beam} related parameters for each UL channel / signal.

[0220] For example, this embodiment may be applied assuming that the above-described embodiment 1-1 does not apply (i.e., the same frequency / time domain resources are used for the macro cell and the UL Rx point).

[0221] Example 1-2-1

[0222] UL channels / signals for the macro cell (e.g., resources / resource sets of UL channels / signals) and UL channels / signals for the UL Rx point (e.g., resources / resource sets of UL channels / signals) can be set separately.

[0223] For example, PUCCH resources for a macro cell and PUCCH resources for a UL Rx point can be set separately.

[0224] Additionally or alternatively, a codebook-based (CB) / non-codebook-based (NCB) SRS resource set for the macro cell and a CB / NCB SRS resource set for the UL Rx point may be separately configured. Accordingly, PUSCH transmission scheduling for the macro cell and PUSCH transmission scheduling for the UL Rx point may be distinguished through the SRI (SRS resource indicator) field and / or codepoint distinction of the SRI field in the DCI.

[0225] Additionally or alternatively, SRS resources / SRS resource sets can be configured per target (e.g., macro cell and UL Rx point), thereby distinguishing PUSCH transmissions for the macro cell from PUSCH transmissions for the UL Rx point.

[0226] Additionally or alternatively, CG (configured grant) PUSCH resources may be set for each (e.g., macro cell and UL Rx point), and accordingly, CG PUSCH transmission scheduling for the macro cell and CG PUSCH transmission scheduling for the UL Rx point may be distinguished.

[0227] Additionally or alternatively, PRACH resources for the macro cell and PRACH resources for the UL Rx point may be configured independently (or differently).

[0228] Example 1-2-2

[0229] UL channel / signal related parameters (e.g., power control (PC), timing advance (TA), uplink beam related parameters) for the macro cell and UL channel / signal related parameters (e.g., PC, TA, uplink beam related parameters) for the UL Rx point can be set independently (or differently). That is, for resources for the same UL channel / signal, the PC / TA / beam related parameters for the macro cell and the PC / TA / beam related parameters for the UL Rx point can have different values.

[0230] For example, for the same PUCCH resource, multiple PC / TA / beam related parameters (e.g., two) can be set / indicated for the macro cell and the UL Rx point. That is, the terminal can utilize a specific parameter among the multiple uplink transmission parameters depending on whether the transmission target is the macro cell or the UL Rx point. Additionally or alternatively, if the base station is set / indicated to simultaneously transmit the resource for which the multiple transmission parameters are set / indicated to the macro cell and the UL Rx point, the terminal can utilize each transmission parameter to simultaneously transmit the resource to the macro cell and the UL Rx point.

[0231] Example 1-3

[0232] The base station can configure the macro cell and the UL Rx point to be associated with different CORESET full indices. Accordingly, the PC / TA / beam-related parameters / resources, etc. associated with the first CORESET full index are distinguished from the PC / TA / beam-related parameters / resources, etc. associated with the second CORESET full index, so that transmission parameters can be configured / applied independently (or differently) for each target (i.e., the macro cell and the UL Rx point). For example, for uplink transmission to a UL Rx point physically located different from the macro cell, power control, timing advance, and uplink beam-related parameters / resources can be configured / managed separately (for each CORESET full index).

[0233] For example, the present embodiment may be applied to a case where the uplink for a macro cell and the uplink for a UL Rx point are allocated within the same UL BWP.

[0234] Example 1-3-1

[0235] When the macro cell and the UL Rx point are set to be associated with different CORESET full indices, the terminal can be made to perform only uplink transmission for the CORESET full index associated with the UL Rx point.

[0236] For example, in M-DCI based M-TRP operation, only uplink transmission can be configured / instructed for a specific CORESET pool index. In this case, similar to the configuration of two CB / NCB SRS resource sets in the M-TRP STxMP (simultaneous transmission across multi-panel) PUSCH transmission scheme, the CB / NCB SRS resource set for the macro cell and the CB / NCB SRS resource set for the UL Rx point can be configured separately (i.e., two distinct CB / NCB SRS resource sets are configured for the UE). Accordingly, a one-to-one association may exist between the CB / NCB SRS resource set for the macro cell and a specific CORESET pool index (e.g., the first CORESET pool index), and a one-to-one association may exist between the CB / NCB SRS resource set for the UL Rx point and another specific CORESET pool index (e.g., the second CORESET pool index).

[0237] In PUSCH scheduling, the target of uplink transmission (i.e., macro cell or UL Rx point) may vary depending on which of the two SRS resource sets includes an SRI indication in the UL grant DCI. Accordingly, power control, timing advance, and uplink beam-related parameters for uplink transmission may be applied differently for each target. In addition, when the base station is configured / instructed to simultaneously transmit PUSCH to the macro cell and the UL Rx point by indicating both SRIs related to the two SRS resource sets (i.e., two SRIs) by utilizing multiple SRI indications through the UL grant DCI, the UE may simultaneously transmit the corresponding PUSCH to the macro cell and the UL Rx point by utilizing each transmission parameter.

[0238] For PUCCH / SRS, power control, timing advance, and uplink beam related parameters for the macro cell and / or UL Rx point may be applied during UE uplink transmission, depending on which one or more CORESET full indices (or which one or more CB / NCB SRS resource sets) the resource is associated with.

[0239] Example 1-3-2

[0240] In S-DCI-based M-TRP operation, similar to the PUSCH repetition method (assuming that the uplink for the macro cell and the uplink for the UL Rx point are allocated within the same UL BWP as described above), a CB / NCB SRS resource set for the macro cell and a CB / NCB SRS resource set for the UL Rx point may be separately configured without setting a CORESET full index. In this case, since the two SRS resource sets have a one-to-one correspondence with a specific PUSCH TO (transmission occasion) group during PUSCH repetition transmission, the UE can perform PUSCH repetition transmission for the macro cell and the UL Rx point as the base station schedules PUSCH repetition transmission.

[0241] For example, in the first TO group, PUSCH repeated transmission may be performed for the macro cell, and in the second TO group, PUSCH repeated transmission may be performed for the UL Rx point. Here, transmission may be performed for the S-TRP (i.e., either the macro cell or the UL Rx point) according to the SRI indication (or by the SRS resource set indicator field). For each TO group, the UE may utilize specific parameters associated with the corresponding target / SRS resource set among uplink transmission parameters (e.g., power control, timing advance, uplink beam-related parameters) related to multiple SRS resource sets depending on whether the transmission target is the macro cell or the UL Rx point (or depending on which SRS resource set-related SRI, TPMI is indicated).

[0242] For PUCCH / SRS, macro cell-specific or UL Rx point-specific power control, timing advance, and uplink beam-related parameters may also be applied during UE uplink transmission, depending on which CB / NCB SRS resource set the resource is associated with.

[0243] Example 1-4

[0244] The base station can configure the macro cell and the UL Rx point to be associated with different joint and / or separate (UL) TCI states in the unified TCI framework. In this case, since the different joint / separate (UL) TCI states each have information related to power control, timing advance, and transmission beam, the base station can distinguish whether the target of the uplink transmission of the UE is the macro cell or the UL Rx point depending on which joint / separate (UL) TCI state it utilizes for uplink transmission.

[0245] For example, in an extension of the integrated TCI state for M-TRP operation, the number of receive and transmit common beams may be extended to two for TRP-specific common beam management, and these two indicated TCI states (i.e., joint TCI state and / or split UL TCI state) may be applied for uplink transmission for the macro cell and UL Rx point.

[0246] Example 2

[0247] This embodiment relates to a method for acquiring TA of a terminal for a UL Rx point.

[0248] In the examples of Embodiment 1 described above, HARQ process IDs can be defined / configured for the macro cell and the UL Rx point, respectively. In this way, power control, TA, and transmission beam-related parameters for uplink transmission can be applied to each of the HARQ process ID for the macro cell and the HARQ process ID for the UL Rx point, respectively. Even if it is assumed that the macro cell and the UL Rx point are connected through an ideal backhaul, considering that it is difficult to actually implement soft combining of uplink signals received from terminals at the macro cell and the UL Rx point in the decoding fronthaul due to the complexity, it may be appropriate to distinguish transmission-related parameters through a separate HARQ process for each target.

[0249] As mentioned above, since the UL Rx point can only perform UL reception without a DL Tx chain in order to reduce base station installation costs, there is a restriction that DL RS transmission cannot be performed to the terminal. As a result, the terminal cannot measure / determine the DL slot boundary (or reference point) for TA application during uplink transmission to the UL Rx point, and since there is no SSB transmission from the UL Rx point, there is no reference information for random access preamble selection and / or random access preamble transmission timing during RACH / PRACH transmission for TA acquisition, resulting in uncertainty in the terminal operation.

[0250] Below, various examples of the present disclosure related to obtaining timing advance information for a UL Rx point for uplink transmission of a terminal to the UL Rx point are described.

[0251] Example 2-1

[0252] This embodiment relates to the definition or setting of a reference point for applying a timing advance (TA) value (e.g., the value of the N_TA and / or N_TA,offset parameters) after the terminal acquires the TA for the UL Rx point. The reference point may correspond to the boundary of a downlink radio frame for applying the TA value.

[0253] Example 2-1-1

[0254] The UE may expect the reference point of the UL Rx point to be identical to the DL reference point of the macro cell. Additionally or alternatively, a constraint may be applied in the deployment / implementation of the base station that the DL reference point of the macro cell and the reference point of the UL Rx point be identical. In this case, the reference point definition for a specific cell (e.g., SpCell / SCell) of the UE as follows may be applied to the UL Rx point.

[0255] Regarding terminal transmission timing, the terminal may have the capability to follow the frame timing change of the reference cell when transmitting a PUSCH on the CG (configured grant) resource for SDT (small data transmission) in the RRC connected state or in the RRC inactive state. As described above, the uplink frame transmission is performed at the time of reception of the first detected path (in time) of the corresponding downlink frame from the reference cell (N TA + N TA,offset )*T c It can be performed at the previous point. For the serving cell(s) of the PTAG, the UE can use the SpCell as a reference cell to derive the transmission timing for the cells of the PTAG. For the serving cell(s) of the STAG, the UE can use any one of the activated SCells as a reference cell to derive the transmission timing for the cells of the STAG. The initial transmission timing accuracy and gradual timing adjustment requirements of the UE can be defined.

[0256] Example 2-1-2

[0257] For defining the reference point of the UL Rx point, an offset value between the reference point of the UL Rx point and the DL reference point of the macro cell may be set / indicated from the base station to the terminal. This may be applied when there is a difference in the reference points between the macro cell and the UL Rx point, or an offset value of 0 may be set / indicated even when there is no difference. When there are multiple UL Rx points associated with one macro cell, offset values ​​may be set / indicated separately (or differently) for each of the multiple UL Rx points.

[0258] For example, the offset value is N of the TA command as described above.TA value (where T A =0, 1, 2, ..., 3846) or T in the relative TA command as described above. A =0, 1, 2, ..., 63 (multiples of) can be expressed.

[0259] As another example, the offset value may be predefined as a specific value (e.g., a positive / negative real number), and one of the predefined values ​​may be set / indicated to the terminal as an offset value relative to the reference point of the UL Rx point.

[0260] Regarding the term reference point, since DL radio frames do not exist / are not defined at the UL Rx point, the reference point for the UL Rx point may also be defined as UL reference point or virtual point or virtual reference point instead of the term DL reference point.

[0261] Example 2-1-3

[0262] N for UL Rx point to define the reference point of UL Rx point TA,offset The value can be defined / set. N for UL Rx point TA,offset The parameter is N for the macro cell TA,offset It can be defined / set as a parameter distinct from the parameter. This can be applied when there is a difference in the reference point between the macro cell and the UL Rx point, or when there is no difference, it can be applied when the same N as the macro cell is used. TA,offset The value may be defined / set. If there are multiple UL Rx points associated with one macro cell, N for each of the multiple UL Rx points TA,offset The values ​​of the parameters may be set / indicated separately (or differently).

[0263] N for macro cells (i.e. existing) TA,offset The parameters correspond to TDD / FDD band-specific values ​​and are either predefined or signaled to the terminal by the base station settings. N for the UL Rx point is distinct from this. TA,offset The parameters may be set for the terminal by the base station and / or may be predefined.

[0264] In the above-described embodiment 2-1, the base station can signal to the terminal whether one of embodiments 2-1-1, 2-1-2, and 2-1-3 is applied depending on whether there is a difference in reference points between the macro cell and the UL Rx point. For example, in embodiments 2-1-2 and 2-1-3, an offset value or N for (multiple) UL Rx points TA,offset The base station can signal to the terminal information about when the value is applied.

[0265] Example 2-2

[0266] This embodiment relates to a method for acquiring a TA for a UL Rx point of a terminal and a method for indicating / updating a TA for the UL Rx point. In the examples below, for managing a TA value for the UL Rx point, the TA value for the UL Rx point may be managed as a TAG different from that of the macro cell, or may be managed through a predetermined offset value for the TA value of the macro cell.

[0267] Example 2-2-1

[0268] Similar to Example 2-1, if a reference point for uplink transmission for a UL Rx point is defined / configured, the terminal can transmit uplink transmission for the configured / indicated UL Rx point based on the reference point. In this case, the base station may not perform a separate operation for acquiring TA of the terminal. Thereafter, the base station can provide a TA command for the UL Rx point by utilizing an absolute / relative TA command (e.g., MAC CE) to correct the TA value for the UL Rx point of the terminal.

[0269] Example 2-2-2

[0270] A terminal can transmit a RACH / PRACH to a UL Rx point. For example, a RACH / PRACH can be transmitted to the UL Rx point based on a PDCCH order. The PDCCH order can be provided to the terminal from a macro cell. After receiving the RACH / PRACH at the UL Rx point, the base station can indicate a TA value for the UL Rx point to the terminal through an RAR (e.g., an absolute TA command field included in the RAR) transmitted from the macro cell to the terminal. That is, an RAR responding to a RACH / PRACH transmitted to the UL Rx point can be received from the macro cell. For example, the RAR can be received through a CORESET associated with a type-1 CSS (common search space).

[0271] In this regard, applying a PL (path loss) offset to a PRACH transmitted to a UL Rx point based on a PDCCH order may be supported. Determining the DL reference timing for a PRACH transmission to a UL Rx point based on a PDCCH order may be based on a DL RS as defined previously. For example, DL RSs such as SSB and / or CSI-RS of a macro cell may be utilized for determining the DL reference timing for the UL Rx point or may be applied as a PL reference RS. In addition, with respect to the indication of a PL offset for a PRACH transmission based on a PDCCH order, a PL offset associated with a joint / UL TCI state indicated for the UL Rx point in the unified TCI framework may be applied to the PDCCH order-based PRACH transmission.

[0272] Specifically, since the UL Rx point does not transmit SSB, it is required to solve the problem of difficulty in power control and transmission beam information setting for RACH / PRACH transmission. To this end, i) the base station may instruct the terminal to utilize RACH / PRACH resources related to the SSB by instructing the terminal to utilize a specific SSB of the macro cell through a PDCCH order, and further, the terminal may apply the SSB as a transmission beam RS and / or PL RS (or PL reference RS) and transmit RACH / PRACH based thereon. Alternatively, ii) the base station may instruct the terminal to utilize RACH / PRACH resources related to the SSB by instructing the terminal to utilize a specific SSB of the macro cell through a PDCCH order, and the terminal may apply a transmission beam RS and / or PL RS determined in a different manner instead of the SSB of the macro cell and transmit RACH / PRACH based thereon. Alternatively, iii) the terminal may be allowed to apply a transmission beam RS and / or PL RS determined in a different manner without the base station's instruction on the SSB. For example, for a RACH / PRACH transmission beam determined in a different manner, a beam management SRS transmitted by the terminal in advance may be utilized as a reference RS of the RACH / PRACH transmission beam.

[0273] Various examples of transmission beam / PL RS application for RACH / PRACH transmission (e.g., i), ii) and / or iii) described above) may be selectively applied (e.g., switched / controlled) by the base station. For example, when the base station transmits a PDCCH order to the UE that triggers RACH / PRACH transmission for the UL Rx point, information indicating whether the UE transmits the RACH / PRACH based on the UE's reception beam for the SSB of the macro cell (e.g., example i) described above) or whether the UE transmits the RACH / PRACH based on a beam direction different from the UE's reception beam for the SSB of the macro cell (e.g., example ii) or iii) described above) may be included in the DCI corresponding to the PDCCH order.

[0274] After transmitting a random access preamble via RACH / PRACH for a UL Rx point, the QCL assumption applied to reception of a RAR (i.e., a PDCCH / DCI scheduling a PDSCH carrying the RAR, and / or a PDSCH carrying the RAR) in response to the random access preamble may be applied as in the following examples. For example, if RACH / PRACH transmission is performed based on an SSB of a macro cell according to example i) described above, the indicated SSB of the macro cell may be utilized as a QCL RS for RAR reception. Alternatively, if RACH / PRACH transmission is performed based on a transmission beam RS and / or PL RS determined in a different manner according to example ii) or iii) described above, the corresponding transmission beam RS and / or PL RS may be utilized as a QCL RS for RAR reception. Additionally or alternatively, the QCL information (or TCI state) set for the CORESET associated with the type-1 CSS used for receiving RAR (of a macro cell) as described above may also be utilized as the QCL RS for receiving RAR.

[0275] When receiving a RAR scheduling PDCCH / DCI after transmitting a RACH / PRACH for a cell supporting both DL and UL, an RA-RNTI applied to monitoring the corresponding PDCCH / DCI is computed based on a RACH occasion (RO), and the PDCCH / DCI can be received based on the corresponding identification information. The RA-RNTI for monitoring the RAR scheduling PDCCH / DCI in response to a RACH / PRACH / random access preamble transmitted for a UL Rx point can be computed according to the following examples. For example, when RACH / PRACH transmission is performed / triggered based on a specific SSB of a macro cell as in the above-mentioned examples i) or ii), an RA-RNTI may be calculated based on information of RO (e.g., symbol index, slot index, frequency domain index) based on the specific SSB of the macro cell, and an RAR scheduling PDCCH / DCI may be received based thereon. Alternatively, when RACH / PRACH transmission is performed that is not based on a specific SSB as in the above-mentioned example iii), a separate RA-RNTI may be calculated by the UE, and an RAR scheduling PDCCH / DCI may be received based thereon.

[0276] The RA-RNTI for the 4-step RACH procedure can be computed as follows. The RA-RNTI associated with a PRACH occasion in which a random access preamble is transmitted can be computed according to the mathematical formula RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id. Here, s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14). t_id is the index of the first slot of the PRACH occasion in the system frame (0 ≤ t_id < 80), and the subcarrier spacing for determining t_id can be based on the subcarrier spacing configuration indices μ(=0, 1, 2, 3) and μ(=5, 6). For example, t_id may correspond to the index of a slot based on 120 kHz subcarrier spacing in the system frame containing a PRACH opportunity. f_id is the index of the PRACH opportunity in the frequency domain (0 ≤ f_id < 8). ul_carrier_id is the index of the UL carrier used for random access preamble transmission, and its value can be 0 for a normal uplink (NUL) carrier and 1 for a supplementary uplink (SUL) carrier. In a 2-step RACH procedure, the MSGB-RNTI associated with a PRACH occasion during which a random access preamble is transmitted can be calculated according to the following equation: MSGB-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id + 14 × 80 × 8 × 2.

[0277] The examples of Embodiment 2-2 can also be applied when a UE transmits a RACH / PRACH to perform initial access. For example, RACH / PRACH information related to a UL Rx point (e.g., a higher layer information element RACH-config including information about RACH resources such as an SSB index, a RACH preamble, and a RACH opportunity) can be included in a specific system information block (SIB). Based on the information included in the SIB, a RACH / PRACH can be transmitted for the UL Rx point when the UE performs an initial access procedure.

[0278] Example 2-2-3

[0279] A set of SRS resources and / or SRS resources for RACH-like SRS may be separately configured for a terminal. The base station may, based on reception of a RACH-like SRS transmitted by the terminal, provide the terminal with a TA command for the UL Rx point by utilizing an absolute / relative TA command (e.g., MAC CE) to correct a TA value for the UL Rx point of the terminal. The specific SRS resources for the aforementioned RACH-like SRS may be configured with time / frequency domain resources of N symbols or more and X kHz bandwidth or more (wherein N and X are each a positive natural number). Accordingly, the base station can solve the problem of inaccurate TA acquisition due to insufficient granularity in the existing SRS reception.

[0280] General devices to which the present disclosure may be applied

[0281] FIG. 12 is a block diagram illustrating a wireless communication device according to one embodiment of the present disclosure.

[0282] Referring to FIG. 12, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR).

[0283] A first wireless device (100) includes 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) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal 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 perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0284] A second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of 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 perform some or all of the processes controlled by the processor (202), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0285] Hereinafter, hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in the present disclosure, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in the present disclosure.

[0286] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing 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, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0287] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0288] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of the present disclosure, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure, via one or more antennas (108, 208). In the present disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0289] The embodiments described above are combinations of components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form embodiments or incorporated as new claims through post-application amendments.

[0290] It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics thereof. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0291] The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the methods of various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on / in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement the features described in the present disclosure. The storage medium can include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid state memory devices, and can include non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. The memory optionally includes one or more storage devices remotely located from the processor(s). The memory or, alternatively, the non-volatile memory device(s) within the memory comprise a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and / or firmware stored on any of the machine-readable media, which may control the hardware of the processing system and allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0292] Here, the wireless communication technology implemented in the wireless device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device (100, 200) of the present disclosure may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device (100, 200) of the present disclosure can include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PAN) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0293] The method proposed in this disclosure is explained with a focus on examples applied to 3GPP LTE / LTE-A and 5G systems, but can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

Claims

1. A step of receiving, by a terminal, from a first network node first information related to at least one of a synchronization signal / physical broadcast channel block (SSB) of a first network node or a reference signal (RS) of the first network node; A step of transmitting a random access preamble to a second network node by the terminal based on the first information; and A step of receiving, by the terminal, a random access response (RAR) in response to the random access preamble from the first network node, A method wherein the RAR includes second information related to timing advance (TA) for the second network node.

2. In paragraph 1, A method wherein the downlink reference timing for the random access preamble transmission is based on at least one of the SSB or the RS of the first information.

3. In paragraph 1, A method wherein the pathloss offset for the random access preamble transmission is based on at least one of the SSB or the RS of the first information.

4. In paragraph 1, A method wherein the first information is included in a physical downlink control channel order (PDCCH order) from the first network node to the terminal.

5. In paragraph 1, A method wherein a quasi co-location (QCL) assumption for at least one of a physical downlink shared channel (PDSCH) carrying the RAR or a PDCCH scheduling the PDSCH is based on the SSB of the first information.

6. In paragraph 1, A quasi co-location (QCL) assumption for one or more of the PDSCH carrying the RAR or the PDCCH scheduling the PDSCH is: The RS of the above first information, or QCL information set for a control resource set (CORESET) associated with a type-1 common search space (CSS) for the first network node A method based on one or more of the following.

7. In paragraph 1, The RA-RNTI (random access-radio network temporary identifier) ​​related to monitoring of a PDCCH that schedules a PDSCH carrying the RAR or monitoring of downlink control information (DCI) including scheduling information for the PDSCH, A method calculated based on at least one of a symbol index, a slot index, or a frequency domain index of a PRACH (physical random access channel) opportunity based on the SSB of the first information.

8. In paragraph 1, A method wherein the second information included in the RAR is applied to the second TAG based on the first timing advance group (TAG) associated with the first network node and the second TAG associated with the second network node being set for the terminal.

9. In paragraph 8, A method wherein uplink transmission from the terminal to the second network node is performed based on a first transmission configuration indicator (TCI) state for the first TAG and a second TCI state for the second TAG being set or indicated to the terminal.

10. In paragraph 9, A method wherein the path loss offset associated with the second TCI state is applied to the random access preamble transmission.

11. In paragraph 1, A method wherein, prior to receiving the first information, configuration information for one or more of the SSBs of the first network node or one or more reference signals (RSs) of the first network node is provided to the terminal.

12. In paragraph 1, The above first network node corresponds to a macro cell, The above second network node corresponds to an uplink receiving point, method.

13. In paragraph 12, A method wherein the above uplink reception point supports uplink reception from one or more terminals including the terminal, and does not support downlink transmission to the one or more terminals.

14. One or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receive first information related to at least one of a synchronization signal / physical broadcast channel block (SSB) of a first network node or a reference signal (RS) of the first network node, by a terminal, from the first network node through the at least one transceiver; transmitting a random access preamble based on the first information to the second network node through the one or more transceivers by the terminal; and A random access response (RAR) in response to the random access preamble is set to be received by the terminal from the first network node through the one or more transceivers, A device wherein the RAR includes second information related to timing advance (TA) for the second network node.

15. A step of transmitting, by the first network node, first information related to at least one of the SSB (synchronization signal / physical broadcast channel block) of the first network node or the reference signal (RS) of the first network node to the terminal; and A step of transmitting, by the first network node, to the terminal a random access response (RAR) in response to a random access preamble transmitted by the terminal to the second network node based on the first information, A method wherein the RAR includes second information related to timing advance (TA) for the second network node.

16. One or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Transmitting first information related to at least one of a synchronization signal / physical broadcast channel block (SSB) of a first network node or a reference signal (RS) of the first network node to a terminal through the at least one transceiver by the first network node; and A random access response (RAR) is set to be transmitted by the first network node to the terminal through the one or more transceivers in response to the random access preamble transmitted by the terminal to the second network node based on the first information, A device wherein the RAR includes second information related to timing advance (TA) for the second network node.

17. One or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions for performing a method according to any one of claims 1 to 11 based on execution by said one or more processors.

18. One or more non-transitory computer-readable media storing one or more instructions that are executed by one or more processors to control the performance of a method according to any one of claims 1 to 11.

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