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

Abstract

Disclosed are a method and device for uplink transmission and reception in a wireless communication system. The method according to an embodiment of the present disclosure may comprise the steps in which: a terminal receives, from a base station, higher layer signaling including at least one physical random access channel (PRACH) configuration; and the terminal transmits a PRACH to the base station on the basis of the at least one PRACH configuration, wherein the at least one PRACH configuration includes a first parameter set related to a first synchronization signal block (SSB) group and a second parameter set related to a second SSB group, and each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group can be mapped to a plurality of random access channel occasions (ROs) on the basis of an index of the at least one first SSB and an index of the at least one second SSB.

Description

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

[0005] In addition, an additional technical problem of the present disclosure is to provide a method and device for transmitting and receiving a random access preamble.

[0006] In addition, an additional technical problem of the present disclosure is to provide a method and device for setting different amounts of RACH (random access channel) opportunities for each SSB (synchronization signal block) index.

[0007] 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 can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0008] A method according to one embodiment of the present disclosure comprises: receiving, by a terminal, from a base station, upper layer signaling including at least one physical random access channel (PRACH) configuration; and transmitting, by the terminal, a PRACH to the base station based on the at least one PRACH configuration, wherein the at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, wherein each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group can be mapped to a plurality of random access channel occasions (ROs) based on an index of the at least one first SSB and an index of the at least one second SSB.

[0009] According to another embodiment of the present disclosure, a method comprises the steps of: transmitting, by a base station, upper layer signaling including at least one physical random access channel (PRACH) configuration to a terminal; and receiving, by the base station, a PRACH from the terminal based on the at least one PRACH configuration, wherein the at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, wherein each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group can be mapped to a plurality of random access channel occasions (ROs) based on an index of the at least one first SSB and an index of the at least one second SSB.

[0010] According to various embodiments of the present disclosure, a method and apparatus for performing uplink transmission and reception in a wireless communication system can be provided.

[0011] Additionally, various embodiments of the present disclosure may provide a method and device for transmitting and receiving a random access preamble.

[0012] In addition, various embodiments of the present disclosure provide a method and device for setting different amounts of RACH opportunities for each SSB index.

[0013] 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.

[0014] 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.

[0015] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0016] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0017] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0018] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied.

[0019] FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0020] 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.

[0021] FIG. 7 is a flowchart illustrating a method of performing operations for an NES according to one embodiment of the present disclosure.

[0022] FIG. 8 is a diagram for explaining operations related to an SSB-less secondary cell according to one embodiment of the present disclosure.

[0023] FIG. 9 is a flowchart illustrating a method for a terminal to perform a communication procedure according to one embodiment of the present disclosure.

[0024] FIG. 10 is a flowchart illustrating a method for a base station to perform a communication procedure according to one embodiment of the present disclosure.

[0025] FIG. 11 is a diagram illustrating an SSB to RO mapping method according to one embodiment of the present disclosure.

[0026] FIG. 12 illustrates a flexible network topology to which some examples of the present disclosure may be applied.

[0027] FIG. 13 is a block diagram illustrating a wireless communication device according to one embodiment of the present disclosure.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] The present disclosure describes a wireless communication network or a wireless communication system, and operations performed in the 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 in a process of transmitting or receiving a signal to or between terminals connected to the wireless network.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] For clarity, the description is based on the 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.

[0038] 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).

[0039] 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).

[0040] Abbreviations for terms that may be used in this disclosure are defined as follows.

[0041] - BM: beam management

[0042] - CQI: Channel Quality Indicator

[0043] - CRI: Channel state information - reference signal resource indicator

[0044] - CSI: Channel State Information

[0045] - CSI-IM: Channel State Information - Interference Measurement

[0046] - CSI-RS: Channel state information - reference signal

[0047] - DMRS: Demodulation Reference Signal

[0048] - FDM: frequency division multiplexing

[0049] - FFT: fast Fourier transform

[0050] - IFDMA: interleaved frequency division multiple access

[0051] - IFFT: inverse fast Fourier transform

[0052] - L1-RSRP: Layer 1 reference signal received power

[0053] - L1-RSRQ: Layer 1 reference signal received quality

[0054] - MAC: Medium Access Control

[0055] - NZP: non-zero power

[0056] - OFDM: orthogonal frequency division multiplexing

[0057] - PDCCH: Physical downlink control channel

[0058] - PDSCH: Physical downlink shared channel

[0059] - PMI: precoding matrix indicator

[0060] - RE: resource element

[0061] - RI: Rank indicator

[0062] - RRC: Radio Resource Control

[0063] - RSSI: Received signal strength indicator

[0064] - Rx: Reception

[0065] - QCL: quasi co-location

[0066] - SINR: signal to interference and noise ratio

[0067] - SSB (or SS / PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

[0068] - TDM: Time Division Multiplexing

[0069] - TRP: transmission and reception point

[0070] - TRS: Tracking Reference Signal

[0071] - Tx: transmission

[0072] - UE: user equipment

[0073] - ZP: Zero Power

[0074] System General

[0075] 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.

[0076] 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.

[0077] 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.

[0078] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0079] 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.

[0080] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0081] 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.

[0082] 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.

[0083] μΔf=2 μ ·15 [kHz]CP015 Normal 130 Normal 260 Normal, Extended 3120 Normal 4240 Normal

[0084] NR supports multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in traditional cellular bands, when the SCS is 30 kHz / 60 kHz, it supports dense-urban, lower latency, and wider carrier bandwidth, and when the SCS is 60 kHz or higher, it supports a bandwidth larger than 24.25 GHz to overcome phase noise. The NR frequency band is defined by two types of frequency ranges (FR1, FR2). FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 can mean millimeter wave (mmW).

[0085] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1410MHz - 7125MHz 15, 30, 60kHz FR224250MHz - 52600MHz 60, 120, 240kHz

[0086] 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 = It consists of 10 subframes with a duration of 1ms. 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 slotare aligned temporally with the start of the OFDM symbol. Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be used. Table 3 shows the number of OFDM symbols per slot (N) in a general CP. 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.

[0087] μN symb slot N slot frame,μ N slot subframe,μ01410111420221440431480841416016

[0088] μN symb slot N slot frame,μ N slot subframe,μ212404

[0089] 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 illustrated 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. With respect to physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered.

[0090] Hereinafter, the physical resources that can be considered in the NR system will be examined in detail. First, with respect to antenna ports, antenna ports are defined such that the channel through which a symbol on the antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. If the large-scale property 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, then two antenna ports can be said to have a QC / QCL (quasi co-located or quasi co-location) relationship. Here, the large-scale property includes 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. Referring to Fig. 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,μ represents the maximum transmission bandwidth, which may vary not only between numerologies but also between uplink and downlink. In this case, one resource grid may be configured for each μ and antenna port p. Each element of the resource grid for μ and antenna port p is referred to as a resource element and is uniquely identified by an index pair (k, l').

[0092] 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'. Common resource block 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 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 in a portion of the bandwidth of the wideband CC, rather than the entire bandwidth. 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, a base station can configure multiple BWPs even within a single CC configured for a terminal. For example, a BWP occupying a relatively small frequency domain can be configured in a PDCCH monitoring slot, while the PDSCH indicated by the PDCCH can be scheduled on a larger BWP.

[0106] Alternatively, if UEs are concentrated in a specific BWP, some UEs can be assigned to different BWPs for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, some spectrum in the middle of the total bandwidth can be excluded and both BWPs can be assigned within the same slot. In other words, the base station can assign at least one DL / UL BWP to UEs associated with a wideband CC.

[0107] The base station can activate at least one DL / UL BWP among the DL / UL BWP(s) configured at a specific point in time (by L1 signaling or MAC CE (Control Element) or RRC signaling, etc.). In addition, the base station can instruct switching to another configured DL / UL BWP (by L1 signaling or MAC CE or RRC signaling, etc.). Alternatively, switching to a designated DL / UL BWP may be performed when a timer value expires based on a timer. In this case, the activated DL / UL BWP is defined as an active DL / UL BWP. However, since the UE may not receive the configuration for the DL / UL BWP when performing the initial access process or before the RRC connection is set up, the DL / UL BWP assumed by the UE in such a situation is defined as the initially active DL / UL BWP.

[0108] 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.

[0109] 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.

[0110] When the 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 (PSS) 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.

[0111] A terminal that has completed an 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 in the PDCCH (S602).

[0112] 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) with the base station (steps S603 to S606). To this end, the terminal may transmit a specific sequence as a preamble via the random access channel (RACH) (steps S603 and S605) and receive a response message to the preamble via the PDCCH and the corresponding PDSCH (steps S604 and S606). In the case of a contention-based RACH, a contention resolution procedure may additionally be performed.

[0113] 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 its intended use.

[0114] 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.

[0115] Table 5 shows an example of the DCI format in the NR system.

[0116] 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

[0117] 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. DCI format 0_0 is used for scheduling of PUSCH in one cell. Information included in DCI format 0_0 is transmitted after being CRC (cyclic redundancy check) scrambled by C-RNTI (cell radio network temporary identifier, Cell RNTI), CS-RNTI (Configured Scheduling RNTI), or MCS-C-RNTI (Modulation Coding Scheme Cell RNTI). DCI format 0_1 ​​is used to indicate scheduling of one or more PUSCHs in one cell, or configured grant (CG) downlink feedback information to a UE. Information included in DCI format 0_1 ​​is transmitted after being CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI (Semi-Persistent CSI RNTI), or MCS-C-RNTI.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.

[0118] 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.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] NES (network energy saving) technology

[0123] Energy conservation at base stations is considered important in wireless communication systems, including 3GPP, because it can contribute to building eco-friendly networks by reducing carbon emissions and reducing operational expenditure (OPEX) for telecommunications companies.

[0124] In particular, the introduction of NR communications requires higher transmission rates, necessitating base stations to be equipped with more antennas and provide services across wider bandwidths and frequency bands. Consequently, recent studies have shown that base station energy costs can account for as much as 20% of total operating expenses (OPEX). Accordingly, various technologies, known as NES, are being adopted to reduce energy consumption, and the standardization of related technologies is expected to continue.

[0125] Depending on the application of NES technology, the base station can perform operations such as controlling on / off for a certain duration in the time domain, controlling transmission / reception resources for UE-common or UE-specific signals / channels, changing the amount of frequency domain resources, controlling transmission power, or turning on / off antenna ports, transmission-reception points (TRPs), etc. in the spatial domain.

[0126] Referring to Figure 7, the base station can identify the NES solution(s) to be applied (S105). The NES solution(s) may be related to signal transmission and reception control (e.g., on / off), beam operation, handover procedures, channel measurement, and reporting. The NES solution(s) to be applied can be adaptively selected or predefined based on current conditions (e.g., cell load level, characteristics of connected terminals, etc.).

[0127] A base station that has identified NES solution(s) can perform signaling for the NES (S110). The specific signaling procedure may vary depending on the identified NES solution(s). For example, the base station may transmit common information about the NES solution(s), transmit configuration information necessary for NES operation to at least one terminal, or transmit control information regarding the progress of NES operation to at least one terminal. In addition, the base station may receive capability information related to the NES from at least one terminal.

[0128] Thereafter, the base station can perform operations for the NES (S115). At this time, the base station can perform operations for the NES based on the previously performed signaling. That is, based on the system information, configuration information, and control information transmitted through the signaling, the base station can turn on / off the transmission and reception of specific signals, turn on / off elements in the spatial domain, or adjust resources for the transmission and reception of measurement signals.

[0129] Through a procedure similar to that shown in Fig. 7, NES technology can be implemented. Examples of NES solutions that can be implemented through a procedure similar to that shown in Fig. 7 are as follows.

[0130] Intra-system energy saving solution: A RAN node can request a neighboring RAN node to switch at least one SSB beam into its inactive cell, or can perform paging using a limited set of beams to inactive terminals (e.g., stationary terminals).

[0131] Inter-system energy saving solution: NG-RAN nodes that own capacity booster cells can autonomously transition those cells to an inactive state.

[0132] SSB-less SCell solution: If SSB or SMTC (SSB-based RRM measurement timing configuration) configuration is not provided for the SCell, the UE can obtain timing reference and AGC source from another serving cell. In FR1 or FR2, the base station can configure intra-band CA or inter-band CA including the SCell without SSB transmission, in which case the SSB / SIB transmission can be triggered by the UE's wake-up signal (WUS). This increases the period of common channels / signals such as SSB, allowing the base station to remain in the sleep state for a longer period of time.

[0133] Cell DTX / DRX Solution: In order to reduce the downlink transmission / uplink reception activity time of a base station, a common periodic cell DTX / DRX pattern (e.g., active and inactive periods) can be set for terminals within a cell having the corresponding feature. Here, the cell DTX pattern and the cell DRX pattern can be set and activated separately, and up to two cell DTX / DRX patterns can be set per MAC entity. When cell DTX is set and activated, at least one of monitoring for SPS opportunities or monitoring PDCCH can be stopped during the cell DTX inactivity period. When cell DRX is set and activated, at least one of transmission on CG resources or SR transmission can be stopped during the cell DRX inactivity period. Cell DTX / DRX can be activated / deactivated via RRC signaling or L1 group common signaling.

[0134] Parameters such as active duration and cycle may be configured for cell DTX / DRX. The active duration is the period during which the UE receives a PDCCH or SPS opportunity and waits to transmit SR or CG, and the cycle specifies the periodic repetition of the active duration and inactive duration. When both cell DTX and cell DRX are configured, parameters such as active duration and cycle are common. If the base station recognizes an emergency call or a public safety-related service (e.g., MPS or MCS), the network may release or deactivate the cell DTX / DRX configuration so as not to affect the service. In addition, at least some overlap is required between the active duration of the connected mode DRX of the UE and the active duration of the cell DTX / DRX. For example, the connected mode DRX cycle of the UE may be a multiple of the cell DTX / DRX cycle, or vice versa.

[0135] Conditional handover (CHO) solution: A CHO procedure is used when the UE determines whether to execute a handover, while NES technology is applied (e.g., when the cell activates or deactivates cell DTX / DRX). In this case, the UE can use NES-specific CHO events to initiate CHO to a candidate cell, and the reception of a DCI that activates the CHO condition(s) set by the NES event indication can be applied as an additional triggering condition for this.

[0136] Spatial and Power Domain Adaptation Solution: To support gNBs for transceiver muting and / or transmit power adaptation, a UE may be configured to report multiple CSI entries in a CSI report based on multiple sub-configurations. Each sub-configuration corresponds to a spatial domain adaptation pattern (e.g., a subset of available spatial elements) and / or a power offset between a data channel (e.g., PDSCH) and CSI-RS. Depending on the application of the spatial and power domain adaptation solution, the CSI configuration, measurement, and / or reporting behavior may be affected.

[0137] SSB-less SCell solution

[0138] Below, we specifically describe the SSB-less SCell solution among the NES solutions.

[0139] Referring to FIG. 8, the base station can transmit configuration information for the SCell to the terminal (S205). That is, the base station can transmit configuration information for CA to provide a service to the terminal through CA operation. Here, the CA operation may be intra-band CA or inter-band CA. For example, the configuration information for the SCell may include information including information for adding the SCell (e.g., sCellToAddModList), and specifically, may include a cell index, a physical cell identifier, information related to DL-UL configuration, information related to BWP, information related to cell DTX / DRX, information related to downlink frequency (e.g., FrequencyInfoDL), etc.

[0140] The terminal can verify parameters for an SSB-less SCell based on configuration information (S210). Specifically, the terminal can verify that the SCell is an SSB-less SCell based on information related to the downlink frequency included in the configuration information, and can verify related parameters. For example, the terminal can determine that the SCell is an SSB-less SCell by verifying the presence of a parameter indicating that the SCell is an SSB-less SCell (e.g., SSBlessSCell), and can verify the timing reference and AGC source for the SCell based on information about the reference cell (e.g., referenceCell). In the case of FIG. 8, the reference cell may be the PCell. Therefore, the terminal can use the PCell as a timing reference and AGC source for communication on the SCell.

[0141] The terminal can determine settings for CA operation (S215). Then, the terminal can perform communication using the PCell and SCell of the base station (S220, S225).

[0142] Adaptation of common signal / channel transmission

[0143] When a common signal / channel is transmitted using the on-demand SSB transmission method, the energy consumption of the base station can be significantly reduced. For example, the base station can transmit SSB on specific cells where the on-demand SSB process is applied, and not transmit SSB on cells where the on-demand SSB process is not applied. In other words, the base station can initially not perform SSB transmission and only perform SSB transmission when the on-demand SSB process is involved.

[0144] However, if SSB, which performs functions such as time / frequency synchronization or RRM measurement, is not transmitted, stable operation of the cell may not be guaranteed from the perspective of the terminal. Considering this, the base station can adjust the transmission of common signals / channels such as SSB, PRACH, and paging. For example, the energy consumption of the base station can be reduced by changing the transmission pattern of SSB (e.g., transmission period, period per SSB candidate index(es), SSB candidate index(es) transmitted within one transmission period, transmission power, etc.) according to the situation.

[0145] For example, in the case of contention-based random access, since the base station does not know the PRACH transmission timing of the terminal, it may attempt to use the PRACH resources from the configured PRACH resources every time, which may increase energy consumption. Considering this, a method for adjusting the amount of PRACH resources can be applied, thereby controlling the energy of the base station. For example, the period of the PRACH resources can be adjusted, the set to be activated among the preset PRACH resource sets #1 and #2 can be indicated, or the amount of RACH resources corresponding to each SSB index can be provided uniformly or non-uniformly.

[0146] PRACH transmission method and parameters

[0147] Before initiating a physical random access procedure, Layer 1 (e.g., Physical Layer) may receive a set of SS / PBCH block indices from upper layers and provide only the corresponding RSRP measurement set to upper layers.

[0148] Before the physical random access procedure begins, Layer 1 may receive the following information from the upper layer:

[0149] - Setting PRACH transmission parameters (e.g., PRACH preamble format, time resources, frequency resources for PRACH transmission).

[0150] - Parameters for determining the root sequence and cyclic shift in the PRACH preamble sequence set (index to the logical root sequence table, cyclic shift (N CS ), set type (no restrictions, restricted set A or restricted set B).

[0151] From a physical layer perspective, a Type-1 L1 random access procedure may include transmitting a random access preamble (Msg1) on the PRACH, a random access response (RAR) message containing PDCCH / PDSCH (Msg2), a PUSCH transmission reserved by a RAR UL grant if applicable, and a PDSCH transmission for contention resolution. From a physical layer perspective, a Type-2 L1 random access procedure may include transmitting a random access preamble on the PRACH, transmitting a PUSCH (MsgA), receiving a RAR message containing PDCCH / PDSCH (MsgB), and transmitting a PUSCH reserved by a fallback RAR UL grant if applicable, and a PDSCH transmission for contention resolution. If a UE is configured with two UL carriers for its serving cell and detects a PDCCH order, the UE can use the UL / SUL indicator field value of the detected PDCCH order to determine the UL carrier for the corresponding PRACH transmission.

[0152] When a random access procedure for a UE is initiated by a PDCCH command, the PRACH transmission may use the same SCS as the PRACH transmission initiated from a higher layer.

[0153] The physical random access procedure for a terminal may be triggered by a PRACH transmission request from a higher layer or a PDCCH command for a cell. The configuration information for PRACH transmission by the higher layer may include at least one of a configuration for PRACH transmission on a cell, a preamble index, a preamble SCS, power for PRACH transmission, information related to an RA-RNTI corresponding to the PRACH transmission, PRACH resources for the cell, and the number of preamble repetitions for the PRACH transmission.

[0154] The terminal may transmit the PRACH in the cell using the selected PRACH format through the resource set determined using the same spatial filter in case of the indicated PRACH resource or preamble repeat transmission, and the transmission power is P PRACH,b,f,c (i) may be.

[0155] For a Type 1 random access procedure, a UE may be provided with N SS / PBCH block (e.g., SSB) indices associated with a PRACH occasion and R contention-based preambles per SS / PBCH block index for each valid PRACH occasion. For a Type 2 random access procedure with a common set of PRACH opportunities, a UE may be provided with N SS / PBCH block indices associated with a PRACH occasion and Q contention-based preambles per SS / PBCH block index for each valid PRACH occasion. A PRACH transmission may be performed in a subset of PRACH opportunities associated with the same SS / PBCH block index within an SSB-RO mapping period for a UE provided with a PRACH mask index.

[0156] System Information Block (SIB)1 or SS / PBCH block index can be mapped to valid PRACH cases in the following order:

[0157] i) First, the increasing order of the preamble index within a single PRACH opportunity.

[0158] ii Second, ascending order of frequency resource index for frequency multiplexed PRACH opportunities.

[0159] iii) Third, ascending order of time resource index for time-multiplexed PRACH opportunities within a PRACH slot.

[0160] iv) Fourth, ascending order of index for PRACH slots

[0161] The association period starting from frame 0 for mapping SS / PBCH block indices to PRACH opportunities is the smallest integer in the set determined by the PRACH setup period according to Table 6. An SS / PBCH block index can be mapped to a PRACH opportunity at least once within the association period. After an integer number of SS / PBCH block indices for PRACH opportunity mapping cycles within the association period. If there is a PRACH opportunity or a PRACH preamble set that is not mapped to an SS / PBCH block index, the SS / PBCH block index may not be mapped to a PRACH opportunity or a PRACH preamble set.

[0162] PRACH setup period (msec) Association period (number of PRACH setup periods) 10 {1, 2, 4, 8, 16} 20 {1, 2, 4, 8} 40 {1, 2, 4} 80 {1, 2} 160 {1}

[0163] The association pattern period may include one or more association periods, and the pattern between the PRACH opportunity and the SS / PBCH block index may be determined to repeat at most every 160 msec. After an integer number of association periods, PRACH epochs that are not associated with the SS / PBCH block index may not be used for PRACH transmission. PRACH opportunities may be consecutively mapped per corresponding SS / PBCH block index. The indexing of the PRACH opportunity indicated by the mask index value may be reset at every mapping period of consecutive PRACH opportunities per SS / PBCH block index. The UE may select the PRACH opportunity indicated by the PRACH mask index value for the indicated SS / PBCH block index in the first available mapping period for PRACH transmission.

[0164] For the indicated preamble index, the order of PRACH opportunities is:

[0165] - First, the ascending order of the index of frequency resources for frequency multiplexed PRACH opportunities.

[0166] - Second, ascending order of time resource index for time-multiplexed PRACH opportunities within a PRACH slot.

[0167] - Third, the index for the PRACH slot can be in ascending order.

[0168] For a PRACH transmission using a specific number of preamble repetitions, the set associated with the preamble repetition transmissions consists of a specific number of valid PRACH opportunities that are temporally consecutive, use the same frequency resources, and are associated with the same one or more SS / PBCH block indices, and each SS / PBCH block index can be associated with the same preamble index in all valid PRACH opportunities within the set.

[0169] How to set up and transmit PRACH resources for NES

[0170] In a basic wireless communication system, equal amounts of RACH opportunities (ROs) can be allocated across different SSB beam indices. When terminals are clustered within a specific area within the coverage area of ​​a specific base station, each terminal may access the RO corresponding to the SSB beam index with the best reception from its current location, potentially resulting in initial access delays. This creates a need to address the issue of requiring more ROs for certain SSB beams / indexes than for others.

[0171] Hereinafter, a method for differently setting the amount of RACH resources mapped to different SSB beam directions within a specific PRACH configuration and an SSB-to-RO mapping pattern of an adaptive RO additionally defined / set according to a PRACH spatial domain adaptation method will be described. In describing the present disclosure, an RO may also be expressed as a PRACH occasion.

[0172] In describing the present disclosure, the description related to RACH opportunities may be primarily applied to, but not limited to, a 4-step RACH procedure (or a Type-1 RACH procedure). The description related to RACH opportunities may also be applied to a 2-step RACH procedure (or a Type-2 RACH procedure) (e.g., RO and / or PUSCH opportunities in a 2-step RACH procedure, etc.).

[0173] FIG. 9 is a flowchart illustrating a method for a terminal to perform a communication procedure according to one embodiment of the present disclosure.

[0174] The terminal can receive upper layer signaling including at least one physical random access channel (PRACH) setting from the base station (S910).

[0175] As an example of the present disclosure, at least one PRACH configuration may include a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group. Here, the first SSB group may include at least one first SSB (e.g., basic (or legacy) SSB(s)), and the second SSB group may include at least one second SSB (e.g., SSB(s) to which PRACH spatial domain adaptation is applied). In addition, the first parameter set may include a number of ROs mapped to at least one first SSB, and the second parameter set may include a number of ROs mapped to at least one second SSB.

[0176] In describing the present disclosure, upper layer signaling may be, but is not limited to, one of system information (e.g., SIB_x (where x is a natural number greater than or equal to 1)), MAC CE among RRC signaling.

[0177] Additionally or alternatively, higher layer signaling (e.g., system information, RRC signaling, or / and MAC CE, etc.) may include information about the number of SSBs included in the first SSB group and the second SSB group. For example, the higher layer signaling may include information about the number of SSBs included in each SSB group, or / and information about the total number of SSBs included in the first SSB group and the second SSB group.

[0178] Additionally or alternatively, the higher layer signaling may include information regarding additional random access channel (RACH) resources to be allocated for at least one second SSB. For example, the higher layer signaling may include information regarding whether additional allocation of RACH resources will be applied for at least one second SSB.

[0179] Additionally, the terminal may receive downlink control information from the base station, including information related to the activation of additional RACH resources. The terminal may additionally allocate / configure RACH resources for at least one second SSB based on the information related to the activation of the additional RACH resources.

[0180] Additionally or alternatively, the terminal may receive at least one of information about a preamble index, a preamble SCS, information related to a corresponding RA-RNTI, PRACH transmission power, and the number of PRACH transmissions (repetitions) from the base station through higher layer signaling (e.g., system information, RRC message, etc.).

[0181] Additionally or alternatively, at least one PRACH configuration may include, but is not limited to, a first PRACH configuration associated with a first SSB group and a second PRACH configuration associated with a second SSB group. The first PRACH configuration may include a first parameter set, and the second PRACH configuration may include a second parameter set.

[0182] As an example of the present disclosure, each of at least one first SSB included in a first SSB group and at least one second SSB included in a second SSB group can be mapped to a plurality of random access channel occasions (ROs) based on an index of at least one first SSB and an index of at least one second SSB.

[0183] For example, multiple ROs may be allocated within a first association period. The multiple ROs may be multiplexed in the frequency / time domain. For example, the multiple ROs may be FDMed in units of two frequency resources, but is not limited thereto. The multiplexing scheme of the multiple ROs in the frequency / time domain may be predefined, but may also be set / instructed by the base station. At least one first SSB and at least one second SSB may be mapped to the multiple ROs in the order described below.

[0184] Specifically, the indices of at least one first SSB and at least one second SSB may be mapped to the plurality of ROs in ascending order of the indices of the at least one first SSB and the at least one second SSB. Each of the at least one first SSB and the at least one second SSB may be mapped to the plurality of ROs in ascending order of the indices of each of the plurality of ROs.

[0185] And, at least one first SSB and at least one second SSB each can be mapped to the plurality of ROs in ascending order of frequency and time resource indices of the plurality of ROs. For example, assume that N ROs (N is a natural number greater than or equal to 1) are allocated to each time resource within the first association period. The SSB having the smallest index among the at least one first SSB and the at least one second SSB can be sequentially allocated (i.e., allocated in ascending order) to each of the N ROs on the first time resource having the smallest time value. And, at least one first SSB and at least one second SSB can be allocated to each of the N ROs on the second time resource following the first time resource in ascending order of indices.

[0186] The terminal can transmit a PRACH to the base station based on at least one PRACH setting (S920).

[0187] As an example of the present disclosure, a terminal may identify at least one third SSB among at least one first SSB and at least one second SSB, wherein a reference signal received power (RSRP) exceeds a threshold. A selection probability of at least one RO of the at least one third SSB may be determined based on a size of an RACH resource allocated to the at least one third SSB. The terminal may identify a specific RO among the at least one RO based on the selection probability of the at least one RO, and perform PRACH transmission (e.g., preamble transmission) based on the specific RO.

[0188] The method described in the example of FIG. 9 may be performed by the first device (100) of FIG. 13. For example, one or more processors (102) of the first device (100) of FIG. 13 may receive upper layer signaling including at least one PRACH configuration from a base station through one or more transceivers (106). The one or more processors (102) may transmit a PRACH to the base station through one or more transceivers (106) based on the at least one PRACH configuration.

[0189] Furthermore, one or more memories (104) of the first device (100) may store commands for performing the method described in the example of FIG. 9 or the examples described below when executed by one or more processors (102).

[0190] FIG. 10 is a flowchart illustrating a method for a base station to perform a communication procedure according to an embodiment of the present disclosure.

[0191] The base station can transmit upper layer signaling including at least one PRACH configuration to the terminal (S1010).

[0192] The base station may transmit (via higher layer signaling) PRACH configuration information to the terminal for each SSB group containing SSB(s) requiring additional RACH resource allocation and each SSB group containing SSB(s) not requiring (additional) RACH resource allocation. The specific configuration of the higher layer signaling has been described with reference to FIG. 9, so a redundant description will be omitted.

[0193] A base station may receive a PRACH from a terminal based on at least one PRACH configuration (S1020). At this time, the PRACH may include at least one preamble mapped to RO(s).

[0194] The method described in the example of FIG. 10 may be performed by the second device (200) of FIG. 13. For example, one or more processors (202) of the second device (200) of FIG. 13 may transmit upper layer signaling including at least one PRACH configuration to a terminal via one or more transceivers (206). One or more processors (102) may receive a PRACH based on at least one PRACH configuration from the terminal via one or more transceivers (106).

[0195] Furthermore, one or more memories (204) of the second device (200) 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 (202).

[0196] Below, we will specifically describe the PRACH spatial domain adaptation method and the SSB-to-RO mapping pattern for adaptive RO.

[0197] Example 1

[0198] Embodiment 1 relates to a PRACH spatial domain adaptation method for an NES terminal. The PRACH spatial domain adaptation method may collectively refer to a method for adding or removing ROs (configured by a base station) within a spatial domain, or / and a method for allocating different amounts of ROs for different SSB beam indices. Each of the detailed embodiments of Embodiment 1 relates to a method for configuring ROs for SSB beam indices (within the spatial domain) (or / and a PRACH spatial domain adaptation method).

[0199] Example 1-1

[0200] Example 1-1 relates to a method for independently providing SSB to RO mapping related parameters for each SSB index / beam through system information.

[0201] When the base station configures / instructs the PRACH configuration to the terminal through system information (e.g., SIB1) (i.e., when the base station transmits the corresponding system information to the terminal), the corresponding system information may include SSB to RO mapping related parameters for each SSB beam / index. In other words, the SSB to RO mapping related parameters can be independently configured / instructed for each SSB beam / index through the corresponding system information.

[0202] In describing the present disclosure, “general SSB beam / index” may collectively refer to an SSB beam / index that does not require PRACH spatial domain adaptation, and “specific SSB beam / index” may collectively refer to an SSB beam / index that requires PRACH spatial domain adaptation.

[0203] As an example of the present disclosure, if a base station sets / instructs a terminal to use N as the number of SSB beams / indexes for a specific PRACH configuration, the base station may provide / set N independent SSB to RO mapping parameters for the terminal, respectively, for the N SSB beams / indexes. As an example, the N SSB to RO mapping parameters may be set to different values. In addition, the SSB to RO mapping parameters may include parameters related to the number of SSBs per RO (e.g., "ssb-perRACH-Occasion"), etc.

[0204] Additionally or alternatively, when N SSB beams / indexes are set / indicated / defined, it is assumed that the number of specific SSB beams / indexes is A and the number of general SSB beams / indexes is B (e.g., A+B=N). In this case, A independent (e.g., different values) SSB-to-RO mapping parameters may be provided to the terminal. Furthermore, one common SSB-to-RO mapping parameter may be provided to the terminal, and during SSB-to-RO mapping, B general SSB beams / indexes may be set based on the common SSB-to-RO mapping parameter.

[0205] Additionally or alternatively, when N SSB beams / indices are set / indicated / defined, it is assumed that the number of specific SSB beams / indices is A and the number of general SSB beams / indices is B (e.g., A+B=N). In this case, two independent (e.g., different valued) SSB to RO mapping parameters (e.g., SSB to RO mapping parameter #1 and SSB to RO mapping parameter #2) may be provided to the terminal. Furthermore, during SSB to RO mapping, A specific SSB beams / indices may be set based on SSB to RO mapping parameter #1, and B general SSB beams / indices may be set based on SSB to RO mapping parameter #2.

[0206] As an example of the present disclosure, SSB beams / indexes can be configured by grouping them into subgroups. For example, when N SSB beams / indexes are divided into M (mutually exclusive) SSB beam / index subgroups, the base station can provide the terminal with independent (e.g., different values) SSB to RO mapping parameters for each SSB beam / index subgroup. Accordingly, the terminal can be configured to perform SSB to RO mapping according to the SSB beam / index(s) corresponding to each subgroup.

[0207] At this time, if a specific value (e.g., 0) among the SSB to RO mapping parameter values ​​is predefined and a specific value is indicated for a specific sub-group, the RO corresponding to the SSB beam / index(s) corresponding to the specific sub-group may be set not to be configured.

[0208] Additionally or alternatively, a sub-group #1 corresponding to all N SSB beams / indexes may be defined, and a sub-group #2 consisting of only some SSB beams / index(s) among the N SSB beams / indexes may be defined. That is, sub-group #2 may be a subset of sub-group #1. The base station may provide independent (e.g., different values ​​of) SSB-to-RO mapping parameters to the terminal for each sub-group, and the terminal may be configured to perform SSB-to-RO mapping according to the SSB beam / index(s) corresponding to each sub-group. In this case, a terminal associated with an SSB beam / index(s) belonging to the sub-group #2 (e.g., a terminal to which an SSB beam / index(s) belonging to the sub-group #2 is indicated / applied / configured) may be configured to perform SSB-to-RO mapping using the SSB-to-RO mapping parameter for the sub-group #2, while ignoring the SSB-to-RO mapping parameter for the sub-group #1.

[0209] Example 1-2

[0210] Embodiments 1-2 relate to a method in which a base station provides SSB beam / index information requiring further RACH resource allocation to a terminal via system information (e.g., SIB1, etc.). Accordingly, RACH resources for specific SSB beams / indexes can be additionally configured / indicated / defined.

[0211] Specifically, when the base station provides the terminal with specific SSB beam / index information that requires more RACH resource allocation, RACH resources can be mapped evenly through one SSB to RO mapping parameter for all SSB beams / indexes, and additional RACH resources can be set / defined / instructed to be allocated for specific SSB beams / indexes.

[0212] Additionally or alternatively, the base station may provide the terminal with some SSB beam / index information that does not require RACH resource allocation along with SSB beam / index information that requires more RACH resource allocation, and a method of changing the SSB beam / index of the corresponding RO may be applied.

[0213] For example, assume that the base station is using SSB beam / index {1, 2, 3, 4} and indicates that more RACH resources are needed for SSB beam / index {1, 2}, and indicates that (additional) allocation of RACH resources is not needed for SSB beam / index {3, 4}. In this case, the base station can be configured to change the RO(s) corresponding to SSB beam / index {3, 4} among the already allocated ROs according to the SSB-to-RO mapping to the RO(s) corresponding to SSB beam / index {1, 2}. Consequently, if there are a total of 4 ROs within a specific period (e.g., association period), the 4 ROs can be configured (by the base station) to be mapped to SSB beam / index {1, 2, 1, 2} instead of SSB beam / index {1, 2, 3, 4}.

[0214] That is, the base station can configure / instruct the terminal to reduce the number of SSB beams / indexes used for SSB-to-RO mapping from N to K (N > K). And, the base station can configure / instruct the terminal to which of the K SSB beams / indexes each of the N SSB beams / indexes should be (newly) mapped or replaced.

[0215] Additionally or alternatively, if the base station only provides some SSB beam / index information to the terminal for which RACH resources do not need to be allocated, a method in which (the base station and / or the terminal) puncture and do not use the corresponding ROs may be applied. For example, if the base station uses SSB beam / index {1, 2, 3, 4} and indicates that RACH resources do not need to be allocated for SSB beam / index {3, 4}, then among the ROs already allocated according to the SSB-to-RO mapping, the RO(s) corresponding to SSB beam / index {3, 4} may be defined as punctured and not used. The puncturing operation proposed here may be performed per SSB beam / index, but may also be performed per SSB beam / index group.

[0216] Additionally or alternatively, multiple RO(s) may be grouped or multiple RACH slot(s) may be grouped, and the base station may transmit to the terminal indication information (e.g., information indicating on / off of RACH resources) related to whether to use (RACH) resources for each RO group and / or each RACH slot group.

[0217] Example 1-3

[0218] Examples 1-3 relate to a method of indicating an SSB beam / index that requires dynamic (e.g., DCI, etc.) on / off of an RO (or activation / deactivation of an RO).

[0219] After the base station configures / instructs the UE to configure RRACH settings via system information (e.g., SIB1, etc.), it may additionally instruct the UE via dynamic instructions (e.g., DCI) on whether to allocate RACH (additional) resources among each SSB beam / index(s). Accordingly, the UE and / or the base station can perform SSB-to-RO mapping based on the PRACH configuration and / or dynamic instructions.

[0220] At this time, a dynamic indication containing information on whether RACH resources are allocated to each SSB beam / index(s) can be configured / indicated / transmitted based on a specific cycle. For example, an association period can be a cycle for setting / indicating / transmitting the dynamic indication. Accordingly, SSB to RO mapping can be newly performed (by the base station) based on information previously provided through the dynamic indication in the association period immediately following the time indicated through the dynamic indication (e.g., DCI, etc.). Here, the length of the association period can be configured to be predetermined by PRACH configuration information provided through system information (e.g., SIB1, etc.).

[0221] As an example of the present disclosure, the base station can set / instruct the terminal regarding whether to allocate RACH resources among each SSB beam / index independently from the information regarding whether to use a specific SSB beam / index. The dynamic instruction described above can be performed for each SSB beam / index or for each SSB beam / index group. For example, the dynamic instruction including information indicating whether to allocate RACH (additional) resources for each SSB beam / index (group) can be transmitted from the base station to the terminal.

[0222] Additionally or alternatively, the base station may perform dynamic indication every time after transmitting the dynamic indication described above to the terminal until the deactivation of the above-described procedure (e.g., SSB to RO mapping, etc.) dynamically indicates. Additionally or alternatively, a validity period, window, and timer (e.g., the validity period of the dynamic indication) may be set / defined for the dynamic indication. Additionally or alternatively, the dynamic indication may be applied only in the period immediately following the period in which the dynamic indication is transmitted (e.g., the associated period), and may be initialized / reset in the next period.

[0223] Example 1-4

[0224] Example 1-4 relates to a method for setting up an SSB-less RO.

[0225] When the terminal performs SSB-to-RO mapping based on PRACH configuration information configured / indicated by the terminal through system information (e.g., SIB1, etc.), the terminal and / or the base station can determine a specific RO as a valid RO (e.g., an SSB-less RO) even if no SSB beam / index is mapped to the specific RO. In addition, the base station can configure / indicate an SSB beam / index to be mapped to the specific RO through dynamic instructions (e.g., DCI).

[0226] That is, if the SSB beam / index is dynamically indicated according to the needs of the base station, the terminal can be configured to perform the RACH procedure by mapping the SSB beam / index indicated by the base station to the SSB-less RO in the next period (e.g., association period). In this case, if the base station does not configure / indicate SSB beam / index information that requires additional RACH resource allocation through dynamic indication (e.g., DCI, etc.), the SSB-less RO can be defined / indicated / configured as not being selected by the terminal in progress of the RACH procedure even if it is a valid RO.

[0227] As an example of the present disclosure, a base station may indicate one SSB beam / index via dynamic instructions (e.g., DCI, etc.), and one or more SSB-less ROs may be configured to be mapped to that SSB beam / index.

[0228] Additionally or alternatively, the base station may be configured with one or more SSB beams / indexes via dynamic instructions (e.g., DCI, etc.), and one or more SSB-less RO(s) may be configured to be mapped based on the one or more SSB / indexes. For example, one or more SSB-less ROs may be configured for one or more SSB beams / indexes configured / indicated by the dynamic instructions according to the SSB beam / index order.

[0229] Example 1-5

[0230] Example 1-5 relates to a method for activating / deactivating all or part of the information set by the base station through system information through dynamic instructions.

[0231] As in the above-described embodiments (e.g., embodiments 1-1, 1-2, 1-3, 1-4, etc.), the base station can set / instruct the terminal about the PRACH configuration and the SSB to RO mapping value through system information (e.g., SIB1, etc.). At this time, the base station can instruct the terminal about whether to activate / deactivate (the PRACH configuration and / or the SSB to RO mapping value included in the system information, etc.) through dynamic instructions (e.g., DCI, etc.).

[0232] For example, let us assume that i) parameters related to SSB to RO mapping are independently provided to the terminal through system information for each SSB index / beam as in Embodiment 1-1, or ii) SSB beam / index information requiring further RACH resource allocation is provided to the terminal through system information as in Embodiment 1-2. In this case, the terminal may not immediately apply the above-described information provided through the system information. The terminal may determine whether to activate / deactivate the above-described information provided through the system information based on a dynamic instruction (e.g., DCI, etc.) additionally received from the base station. That is, the dynamic instruction may include information related to whether the above-described embodiment(s) are applied and / or whether the above-described information included in the system information is activated.

[0233] For example, when a dynamic instruction indicating activation is received from a base station, the terminal may apply / use the method(s) and / or the information described above provided via system information at a specific time (e.g., the immediately following association period after the dynamic instruction is received). As another example, when a dynamic instruction indicating activation is received from a base station, the terminal may set a validity period for the activation (e.g., the method(s) and / or the information described above provided via system information) using a validity period / window / timer, etc. for the activation. Additionally or alternatively, the dynamic instruction may be applied only in the immediately following period (e.g., the association period) in which the dynamic instruction is transmitted, and may be initialized / reset in the next period. Additionally or alternatively, the terminal may apply / use the method(s) and / or the information described above provided via system information until the base station dynamically indicates deactivation.

[0234] As another example of the present disclosure, a terminal may utilize the application of the above-described embodiment(s) and / or the above-described information included in the system information without prior instruction from the base station. However, the base station may also provide explicit enable / disable parameters for each specific cell, BWP, and PRACH configuration.

[0235] For example, if an enabling parameter is provided (or information indicating enable is included in the parameter), the terminal may be configured / defined to determine that PRACH spatial domain adaptation is applied from the time the enabling parameter is provided. In addition, the terminal may expect that parameters related to PRACH spatial domain adaptation are provided by the base station. However, if an enabling parameter is provided (or information indicating disable is included in the parameter), the terminal may be configured / defined to determine that PRACH spatial domain adaptation is not applied until the next instruction.

[0236] Example 1-6

[0237] In one embodiment of the present disclosure, the method / parameter according to the above-described embodiment(s) (e.g., embodiment 1-1, embodiment 1-2, embodiment 1-3, embodiment 1-4, embodiment 1-5, etc.) can also be applied in a subband-wise full duplex (SBFD) environment.

[0238] For example, a base station can configure / instruct a terminal to configure / instruct a basic (or legacy) RO and an additional RO through a basic (or legacy) PRACH configuration. At this time, the RO configured / instructed through the basic PRACH configuration can be distinguished into a basic RO and an additional RO depending on the location of the RO.

[0239] That is, if the RO configured / indicated through the basic PRACH configuration is located in a non-SBFD symbol and / or an SBFD symbol configured / indicated as flexible, the RO may be defined as a basic (or legacy) RO. And, if the RO configured / indicated through the basic PRACH configuration is located in an SBFD symbol configured / indicated as downlink, the RO may be defined as an additional RO.

[0240] As another example of the present disclosure, RO(s) generated by the basic (or legacy) PRACH configuration may be included in the SBFD region (e.g., SBFD symbols configured / indicated for downlink). In this case, some parameters of the basic PRACH configuration may be configured / changed according to specific rules, or may include additional parameters, and the parameters configured / changed according to specific rules or additional parameters may include information / values ​​that cause the RO(s) to be included in the SBFD region. That is, a method of shifting the slot index and / or OFDM symbol index may be applied.

[0241] As another example of the present disclosure, a base station can configure / instruct a basic (or legacy) PRACH configuration and an independent additional PRACH configuration to a terminal, and accordingly, an SBFD-only RO can be configured / instructed. In this case, SSB-to-RO mapping for the basic RO can be performed considering only the basic RO, and SSB-to-RO mapping for the additional RO can be performed considering only the additional RO. In this case, the SSB-to-RO parameters can be individually applied to each RO based on the method / parameter according to the above-described embodiment(s) (e.g., embodiment 1-1, embodiment 1-2, embodiment 1-3, embodiment 1-4, embodiment 1-5, etc.).

[0242] Additionally or alternatively, the base station may separately configure / instruct the terminal to use an SSB beam / index for the additional RO. When performing SSB-to-RO mapping for the additional RO, the terminal may be configured to perform SSB-to-RO mapping using the separately configured / instructed SSB beam / index.

[0243] Example 2

[0244] Embodiment 2 relates to an SSB-to-RO mapping pattern for adaptive RO. Hereinafter, an SSB-to-RO mapping pattern of an adaptive RO additionally set / defined according to the PRACH spatial domain adaptation method according to Embodiment 1 and its detailed embodiments (e.g., Embodiments 1-1, 1-2, 1-3, 1-4, 1-5, and 1-6) is described.

[0245] Example 2-1

[0246] Example 2-1 relates to a method for sequentially mapping SSB beams / indexes regardless of the RACH resource occupancy for each SSB beam / index during SSB to RO mapping.

[0247] Specifically, based on PRACH spatial domain adaptation information configured / indicated through system information (e.g., SIB1, etc.) and / or dynamic instructions (e.g., DCI, etc.), the UE can predetermine the RACH resources allocated to each SSB beam / index. Furthermore, the UE can perform SSB-to-RO mapping in the SSB beam / index order based on the values ​​associated with the RACH resources allocated to each SSB beam / index. At this time, the RACH resource mapping order can be applied as follows:

[0248] - First, the increasing order of the preamble index within a single PRACH opportunity.

[0249] - Second, ascending order of frequency resource index for frequency multiplexed PRACH opportunities.

[0250] - Third, ascending order of time resource index for time-multiplexed PRACH opportunities within a PRACH slot.

[0251] - Fourth, ascending order of the index for the PRACH slot.

[0252] As an example of the present disclosure, it is assumed that eight ROs existing within a specific period (e.g., a PRACH configuration period) are allocated in units of two ROs in a FDM state with respect to each other, and that there are a total of four SSB beams / indexes (e.g., indices 0, 1, 2, 3). When the base station sets the SSB to RO mapping parameter to "1 / 2" for SSB beams / indexes 1 and 2, and sets the SSB to RO mapping parameter to "1" for SSB beam indices 0 and 3, SSB to RO can be mapped (by the terminal / base station) as shown in (a) of FIG. 11.

[0253] Here, setting the SSB to RO mapping parameter value to "1 / 2" means that two ROs are set per SSB beam / index. And, setting the SSB to RO mapping parameter value to "1" means that one RO is set per SSB beam / index.

[0254] As illustrated in (a) of FIG. 11, SSB beam index #0 may be mapped to RO index #0, and SSB beam index #1 may be mapped to RO indices #1 and #2. In addition, SSB beam #2 may be mapped to RO indices #3 and #4, and SSB beam index #3 may be mapped to RO index #5. When SSB to RO mapping is performed as described above, two ROs (e.g., RO indices #6 and #7) remain within a specific period (e.g., association period), and since four SSB beams / indices cannot be mapped once more, the two ROs may be defined / set as unused.

[0255] Additionally or alternatively, if the base station transmits additional information to the terminal indicating that there is no need to allocate RACH resources to a specific SSB beam / index, the terminal may be configured to modify / change the SSB beam / index to be considered when performing SSB-to-RO mapping based on the information about the SSB beam / index actually used in the corresponding cell and the additional information.

[0256] For example, assume that the system information transmitted by the base station to the terminal (e.g., SIB1) includes information that configures / indicates that four SSB beams / indexes (e.g., indices 0, 1, 2, 3) are to be used. Then, if the base station transmits additional information to the terminal indicating that it does not need to allocate RACH resources for SSB beam index #2, the terminal can be configured / defined to perform actual SSB to RO mapping using three SSB beams / indexes (e.g., indices 0, 1, 3).

[0257] Example 2-2

[0258] Example 2-2 relates to a method of first performing SSB to RO mapping evenly for each SSB beam / index and then additionally mapping RO for a specific SSB beam / index.

[0259] The terminal may be configured / defined to first perform SSB-to-RO mapping for all SSB beams / indexes based on SSB-to-RO mapping parameter(s) assigned to SSB beams / indexes that do not require PRACH spatial domain adaptation. Thereafter, the terminal may determine RACH resources that require additional allocation to specific SSB beams / indexes based on PRACH spatial domain adaptation information configured / indicated via system information (e.g., SIB1) and / or dynamic indication (e.g., DCI, etc.). Furthermore, the terminal may be configured / defined to perform additional allocation starting from the remaining ROs after previously performing SSB-to-RO mapping. In this case, the order of RACH resource mapping may be as follows:

[0260] - First, the increasing order of the preamble index within a single PRACH opportunity.

[0261] - Second, ascending order of frequency resource index for frequency multiplexed PRACH opportunities.

[0262] - Third, ascending order of time resource index for time-multiplexed PRACH opportunities within a PRACH slot.

[0263] - Fourth, ascending order of the index for the PRACH slot.

[0264] As an example of the present disclosure, it is assumed that eight ROs existing within a specific period (e.g., a PRACH configuration period) are allocated in units of two ROs in a FDM state, and there are four SSB beams / indexes in total (e.g., indices 0, 1, 2, 3). The base station may set the SSB to RO mapping parameter to "1 / 2" for SSB beams / indexes 1 and 2, and set the SSB to RO mapping parameter to "1" for SSB beam indices 0 and 3. At this time, the terminal may be configured / defined to first perform mapping by applying the SSB to RO mapping parameter 1 to each SSB beam / index, and then additionally map one RO to each SSB beam / index 1 and 2. Accordingly, SSB to RO mapping may be performed as in (b) of FIG. 11.

[0265] Here, setting the SSB to RO mapping parameter value to "1 / 2" means that two ROs are set per SSB beam / index. And, setting the SSB to RO mapping parameter value to "1" means that one RO is set per SSB beam / index.

[0266] That is, as illustrated in (b) of FIG. 11, SSB beam / indexes #0, #1, #2, and #3 can be mapped first to RO indices #0, #1, #2, and #3, respectively. If two ROs (e.g., RO indices #6 and #7) remain within the specific period (e.g., association period) after SSB beam / index #1 is mapped to RO index #4, those ROs cannot be additionally mapped to the four SSB beams / indexes, and thus those two ROs can be defined as unused.

[0267] Additionally or alternatively, if the base station transmits information to the terminal indicating that it does not need to (additionally) allocate RACH resources for a specific SSB beam / index, the terminal may preferentially perform SSB-to-RO mapping by applying the same SSB-to-RO mapping parameters to each SSB beam / index. Thereafter, the terminal may puncture RACH resources (e.g., ROs) mapped to the specific SSB beam / index or treat the ROs as invalid ROs.

[0268] Example 3

[0269] Example 3 relates to the operation of a terminal / base station when applying adaptive RO.

[0270] Depending on the PRACH spatial domain adaptation method, the RACH resource size may vary for each SSB beam / index. The criteria for selecting an RO when a UE performs a RACH procedure may be additionally configured / defined.

[0271] Specifically, the terminal can identify SSB beams / indexes whose RSRP values ​​exceed the RSRP threshold provided by the base station by measuring the RSRP value for each SSB beam / index. Thereafter, the terminal can randomly select one of the ROs for the corresponding SSB beam / index(s) that exceed the RSRP threshold and perform the RACH procedure based on the selected RO.

[0272] Additionally or alternatively, since the size of the RACH resources allocated to each SSB beam / index may vary, the UE may compare the RACH resource sizes of the SSB beams / indexes that exceed the RSRP threshold. Accordingly, the UE may be configured / defined to perform the RACH procedure by preferentially selecting an RO corresponding to an SSB beam / index with more RACH resources (among the SSB beams / indexes that exceed the RSRP threshold).

[0273] That is, the terminal can first select the RO corresponding to the SSB beam / index with the largest RACH resource (among the corresponding SSB beams / indexes that exceed the RSRP threshold) and perform RACH based on the RO. As the size of the RACH resource increases, the probability of collision occurring between different terminals during the MSG (message) 1 (e.g., PRACH preamble) transmission stage can be reduced, and thus the above-described operations and procedures can be applied.

[0274] As an example of the present disclosure, if there are multiple SSB beams / indexes having more RACH resources and the sizes of the RACH resources of the corresponding SSB beams / indexes are the same, the terminal may randomly select at least one of the ROs allocated to the corresponding SSB beams / indexes. That is, if the SSB beams / indexes having the most RACH resources (among the corresponding SSB beams / indexes exceeding the RSRP threshold) are identified and the sizes of the RACH resources of the corresponding SSB beams / indexes are the same, the terminal may select an RO allocated to any of the corresponding SSB beams / indexes.

[0275] Additionally or alternatively, the terminal may compare the sizes of RACH resources among the SSB beams / indexes that exceed the RSRP threshold. The terminal may increase the probability that an RO corresponding to an SSB beam / index that exceeds the RSRP threshold and has more RACH resources is selected, and may decrease the probability that an RO corresponding to an SSB beam / index that exceeds the RSRP threshold and has fewer RACH resources is selected. That is, the selection probability of the RO corresponding to the SSB beam / index(s) that exceed the RSRP threshold may be determined / defined / set based on the size of the RACH resources of each of the SSB beams / index(s). The terminal may select an RO based on the probability and perform a RACH procedure.

[0276] At this time, the base station can transmit to the terminal information including a value for calculating the probability that the corresponding RO is selected. For example, if there are multiple SSB beams / indexes with more RACH resources (e.g., the most RACH resources) and the sizes of the RACH resources of the corresponding SSB beams / indexes are the same, the probability of selection of the RO(s) allocated to the corresponding SSB beams / indexes may be the same. In other words, the larger the size of the RACH resource(s) allocated to each SSB beam / index, the higher the probability of selection of the corresponding SSB beam / index (e.g., the RO of the corresponding SSB beam / index) can be set / defined.

[0277] In describing the present disclosure, descriptions relating to NES terminals and / or NES ROs may be applied to, but are not limited to, systems supporting NES. The descriptions of the above-described embodiments of the present disclosure may also be applied to other systems (e.g., systems involving coverage enhancement (CE) wave-up signals, ambient IoT, and / or duplex enhancement).

[0278] In addition, in the present disclosure, " / " means "and", "or", or "and / or" depending on the context. In addition, it is obvious that examples for the embodiments described above (e.g., Embodiment 1, Embodiment 1-1, Embodiment 1-2, Embodiment 1-3, Embodiment 1-4, Embodiment 1-5, Embodiment 1-6, Embodiment 2, Embodiment 2-1, Embodiment 2-2, Embodiment 3, etc.) can also be included as one of the implementation methods of the present disclosure, and thus can be regarded as a kind of proposed methods. In addition, the proposed methods described above can be implemented independently, but can also be implemented in the form of a combination (or merge) of some embodiments. Information on whether the embodiments are applicable (or information on the rules of the proposed methods) can be defined as a rule so that the base station notifies the terminal through a predefined signal (e.g., a physical layer signal or a higher layer signal). The higher layer can include, for example, one or more of functional layers such as MAC, RLC, PDCP, RRC, and SDAP.

[0279] The methods, embodiments or descriptions for implementing the method proposed in the present disclosure may be applied separately, or one or more methods (or embodiments or descriptions) may be applied in combination.

[0280] FIG. 12 illustrates a flexible network topology to which some examples of the present disclosure may be applied.

[0281] To compensate for incomplete network coverage areas, a network topology that allows for more flexible and resilient split radio access networks (RANs) may be considered. For this purpose, various nodes, such as IAB nodes, relays, and RF repeaters, as illustrated in the example of Figure 12, may be applied, or NTNs may be integrated. For example, an IAB node may correspond to a node that provides wireless backhaul. For example, a relay may refer to any intermediate point, or in the case of a sidelink relay where a terminal functions as a relay, it may collectively refer to a terminal-to-network (U2N) relay and a terminal-to-terminal (U2U) relay. For example, an RF repeater may correspond to a node that simply performs the function of signal amplification and forwarding, while a network-controlled repeater may not only amplify and forward signals but also adjust transmission and reception settings based on information provided by the network. For example, an NTN node may correspond to a satellite or aircraft that provides NTN coverage that is difficult for terrestrial networks to provide. In addition to these examples, various intermediate points can be introduced to improve the network topology.

[0282] Referring to Figure 12, a split RAN can support the division of a base station into a centralized unit (CU) and one or more distributed units (DUs). The CU and DU can correspond to logical units. The CU can be further divided into a control plane (CP) portion and one or more user plane (UP) portions. Since a failure in the CU-CP affects not only the CU-UP but also the DUs, various intermediate points can be introduced to compensate for this.

[0283] An intermediate point may correspond to a terminal or a base station, depending on its relationship to other nodes. For example, an IAB node may include a mobile-termination (MT) portion and a unit (DU). The MT may connect the IAB node to a donor node. The unit (DU) of an IAB node may serve other terminals or connect to other IAB nodes to provide multi-hop wireless backhaul to the terminal. In other words, an IAB node may correspond to a base station in its relationship to a user-side node, and to a terminal in its relationship to a network-side node.

[0284] In some examples of the present disclosure, the description of a terminal may equally apply not only to a user-side endpoint, but also to an intermediate point corresponding to a terminal in a relative relationship with a network-side endpoint. Similarly, in some examples of the present disclosure, the description of a base station may equally apply not only to a network-side endpoint, but also to an intermediate point corresponding to a base station in a relative relationship with a user-side endpoint. However, in most cases where there is no additional description of the operations of three or more entities, the communicating entities in the present disclosure are briefly described as terminals and / or base stations (or first nodes and / or second nodes), and the terms terminal and / or base stations (or first nodes and / or second nodes) are interpreted to include / replace any endpoint or any intermediate point in relation to other nodes.

[0285] That is, in some examples of the present disclosure, for the sake of simplicity of explanation, the subjects of the operation may be referred to as a base station and / or a terminal (or a first node and / or a second node). In addition, the terms base station and / or terminal (or a first node and / or a second node) may also be interpreted / replaced as in the following examples: For example, the base station (or a first node) and the terminal (or a second node) may respectively correspond to a first endpoint and a second endpoint; may respectively correspond to an endpoint and an intermediate point; may respectively correspond to an intermediate point and an endpoint; or may respectively correspond to a first intermediate point and a second intermediate point.

[0286] In the present disclosure, there may be zero or more intermediate points between the base station and the terminal. If intermediate points exist, they may be IAB nodes / relays / RF repeaters / NTN (non-terrestrial network) nodes, or nodes supporting other functions. The intermediate points may be nodes with fixed locations or nodes with unfixed locations.

[0287] General devices to which the present disclosure may be applied

[0288] FIG. 13 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0289] Referring to FIG. 13, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR).

[0290] A first device (100) includes one or more processors (102) and one or more memories (104), and may additionally 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.

[0291] 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 through the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal through the transceiver (106) and then store information obtained from signal processing of the second information / signal in the memory (104).

[0292] 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 device may also mean a communication modem / circuit / chip.

[0293] The second 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). In addition, 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 device may also mean a communication modem / circuit / chip.

[0294] Hereinafter, the hardware elements of the 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 operation 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 operation 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.

[0295] 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.

[0296] 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.

[0297] 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.

[0298] 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.

[0299] 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.

[0300] 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.

[0301] Here, the wireless communication technology implemented in the 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 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 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.

[0302] 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 base station an upper layer signaling including at least one physical random access channel (PRACH) configuration; and A step of transmitting a PRACH to the base station by the terminal based on at least one PRACH setting, The at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, A method wherein each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group is mapped to a plurality of random access channel occasions (ROs) based on an index of the at least one first SSB and an index of the at least one second SSB.

2. In paragraph 1, wherein said at least one PRACH configuration includes a first PRACH configuration associated with said first SSB group and a second PRACH configuration associated with said second SSB group, The above first PRACH setting includes the first parameter set, A method wherein the second PRACH setting comprises the second parameter set.

3. In paragraph 1, The first parameter set includes the number of ROs mapped to at least one first SSB, A method wherein the second parameter set includes the number of ROs mapped to at least one second SSB.

4. In paragraph 1, The above plurality of ROs are multiplexed in the frequency domain within a first association period, A method wherein each of the at least one first SSB and the at least one second SSB is mapped to each of the plurality of ROs in ascending order of the indices of each of the plurality of ROs.

5. In paragraph 1, A method wherein the indices of the at least one first SSB and the at least one second SSB are mapped to the plurality of ROs in ascending order of the indices of the at least one first SSB and the at least one second SSB.

6. In paragraph 1, A method wherein each of the at least one first SSB and the at least one second SSB is mapped to the plurality of ROs in ascending order of frequency and time resource indices of the plurality of ROs.

7. In paragraph 1, A method wherein the upper layer signaling includes information about the number of SSBs included in the first SSB group and the second SSB group.

8. In paragraph 1, A method wherein the upper layer signaling includes information about additional random access channel (RACH) resources to be allocated for the at least one second SSB.

9. In paragraph 8, A method in which downlink control information including information related to activation of the additional RACH resource is transmitted from the base station to the terminal.

10. In paragraph 1, At least one third SSB among the at least one first SSB and the at least one second SSB, wherein the reference signal received power (RSRP) exceeds a threshold value, is identified by the terminal, A method in which a selection probability of at least one RO of the at least one third SSB is determined based on the size of the RACH resource allocated for the at least one third SSB.

11. In paragraph 10, A specific RO among the at least one RO is selected by the terminal according to the selection probability of the at least one RO, A method in which the PRACH transmission is performed based on the specific RO.

12. One or more transceivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receiving upper layer signaling from a base station through the one or more transceivers, the upper layer signaling including at least one physical random access channel (PRACH) configuration; and is configured to transmit a PRACH to the base station through the one or more transceivers based on the at least one PRACH setting; The at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, At least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group are each randomly assigned to a plurality of terminals based on an index of the at least one first SSB and an index of the at least one second SSB.

13. A step of transmitting, by a base station, upper layer signaling including at least one physical random access channel (PRACH) configuration to a terminal; and A step of receiving a PRACH from the terminal by the base station based on at least one PRACH setting, The at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, A method wherein each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group is mapped to a plurality of random access channel occasions (ROs) based on an index of the at least one first SSB and an index of the at least one second SSB.

14. In the base station, the base station: one or more transceivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Transmitting upper layer signaling including at least one physical random access channel (PRACH) configuration to a terminal via the one or more transceivers; and Based on the at least one PRACH setting, the PRACH is set to be received from the terminal through the one or more transceivers, The at least one PRACH configuration includes a first parameter set associated with a first synchronization signal block (SSB) group and a second parameter set associated with a second SSB group, A base station, wherein each of at least one first SSB included in the first SSB group and at least one second SSB included in the second SSB group is mapped to a plurality of random access channel occasions (ROs) based on an index of the at least one first SSB and an index of the at least one second SSB.

15. In a processing device configured to control a terminal, the processing device: 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.

16. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium, wherein the one or more commands are executed by one or more processors to control a device to perform a method according to any one of claims 1 to 11.

Images