Method and device for performing physical downlink control channel order-initiated random access in wireless communication system

Abstract

The present disclosure is for performing physical downlink control channel (PDCCH) order-initiated random access in a wireless communication system. An operation method of a terminal may comprise the steps of: performing a first random access procedure in order to access a base station including a first transmission-reception point (TRP) and a second TRP; receiving a PDCCH order from the first TRP; and performing a second random access procedure for the second TRP on the basis of the PDCCH order.

Description

Method and device for performing random access initiated by physical downlink control channel order in a wireless communication system

[0001] The present disclosure relates to a device and method for performing random access initiated by a physical downlink control channel (PDCCH) order in a wireless communication system.

[0002] Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., long term evolution (LTE), advanced LTE-A (LTE-A), etc.). 5G communication networks (e.g., new radio (NR) communication networks) can support frequency bands above 6 GHz as well as frequency bands below 6 GHz. That is, 5G communication networks can support FR1 bands and / or FR2 bands. 5G communication networks can support various communication services and scenarios compared to LTE communication networks. For example, usage scenarios of 5G communication networks can include enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc.

[0003] Compared to 5G, 6G communication networks can support a wider range of communication services and scenarios. 6G communication networks can meet requirements for ultra-high performance, ultra-high bandwidth, ultra-high space, ultra-high precision, ultra-intelligence, and / or ultra-reliability. 6G communication networks can support diverse and wide frequency bands and be applied to various usage scenarios (e.g., terrestrial communications, non-terrestrial communications, sidelink communications, etc.).

[0004] Meanwhile, in 5G NR, Multiple Transmission and Reception Point (mTRP) technology refers to a technique in which a base station (e.g., gNB) communicates with terminals by utilizing multiple transmission reception points (TRPs) that are physically separated. MTRP technology can solve the problem of reduced quality-of-service (QoS) when terminals located at the cell-edge are far from the base station, and the problem of inter-cell interference from base stations located in different cells. Furthermore, MTPR technology can play a role in providing an additional communication path, a non-line-of-sight (NLOS) path, from the base station in cases where the line-of-sight (NLOS) path from the base station is limited, such as in millimeter wave bands.

[0005] Beam management for TRP in 5G NR can be defined as a set of L1 / L2 procedures that find or maintain the optimal beam required for transmission / reception of each TRP and UE. In particular, for beam management related to analog beamforming, a transmission configuration index (TCI) has been introduced to configure the UE's reception beam for a specific channel / signal, such as PDSCH / CSI-RS / PDCCH. TCI was introduced to dynamically indicate quasi-colocation (QCL) information through downlink control information (DCI) at the base station.

[0006] On the other hand, depending on the status and circumstances of the communication channel, it is necessary to switch between the uplink signal transmission method, Single Transmission and Reception Point (sTRP) mode and Multiple Transmission and Reception Point mode. However, the method and related procedures for switching between Single Transmission and Reception Point mode and Multiple Transmission and Reception Point mode are not defined. Therefore, a method for switching between Single Transmission and Reception Point mode and Multiple Transmission and Reception Point mode is required.

[0007] Meanwhile, the technology that serves as the background for the invention is written to promote understanding of the background for the invention, and may include content that is not a prior art already known to a person with ordinary skill in the field to which the technology belongs.

[0008] The present disclosure may provide a device and method for performing random access initiated by a physical downlink control channel (PDCCH) order in a wireless communication system.

[0009] The present disclosure may provide a device and method for requesting random access to a transmission-reception point (TRP) other than a TRP that transmitted a PDCCH order in a wireless communication system.

[0010] The present disclosure may provide a device and method for indicating a request for random access to another TRP through a PDCCH order in a wireless communication system.

[0011] The present disclosure may provide a device and method for indicating a request for random access to another TRP through a PDCCH order in a wireless communication system.

[0012] The present disclosure may provide a device and method for performing random access in an asymmetric DL (downlink) sTRP (single TRP) / UL mTRP (multiple TRP) situation in a wireless communication system.

[0013] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

[0014] As an example of the present disclosure, a method of operating a terminal in a wireless communication system may include the steps of performing a first random access procedure to access a base station including a first transmission-reception point (TRP) and a second TRP, receiving a physical downlink control channel (PDCCH) order from the first TRP, and performing a second random access procedure for the second TRP based on the PDCCH order.

[0015] As an example of the present disclosure, a method of operating a base station in a wireless communication system may include a step of performing a first random access procedure for connection of a terminal, a step of transmitting a physical downlink control channel (PDCCH) order to the terminal through a first transmission-reception point (TRP), and a step of performing a second random access procedure for a second TRP based on the PDCCH order.

[0016] As an example of the present disclosure, in a wireless communication system, a terminal may include at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed by the processor, control the terminal to perform operations, wherein the operations may include performing a first random access procedure to access a base station including a first transmission-reception point (TRP) and a second TRP, receiving a physical downlink control channel (PDCCH) order from the first TRP, and performing a second random access procedure for the second TRP based on the PDCCH order.

[0017] As an example of the present disclosure, in a wireless communication system, a base station may include at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed by the processor, control the base station to perform operations, wherein the operations may include performing a first random access procedure for connection of a terminal, transmitting a physical downlink control channel (PDCCH) order to the terminal through a first transmission-reception point (TRP), and performing a second random access procedure for a second TRP based on the PDCCH order.

[0018] The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure to be described below.

[0019] The following effects may be achieved by embodiments based on the present disclosure.

[0020] According to the present disclosure, random access to an uplink (UL) transmission-reception point (TRP) can be effectively performed in a wireless communication system.

[0021] According to the present disclosure, asymmetric DL (downlink) sTRP (single TRP) / UL mTRP (multiple TRP) access and operation are enabled in a wireless communication system.

[0022] The effects that can be obtained from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. In other words, unintended effects resulting from implementing the configuration described in the present disclosure can also be derived from the embodiments of the present disclosure by those skilled in the art.

[0023] Figure 1 is a conceptual diagram illustrating an embodiment of a communication system.

[0024] Figure 2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

[0025] Figure 3 is a block diagram illustrating an embodiment of wireless devices performing communication.

[0026] Figure 4a is a block diagram illustrating an embodiment of a transmission path.

[0027] Figure 4b is a block diagram illustrating an embodiment of a receiving path.

[0028] Figure 5 is a conceptual diagram illustrating an embodiment of a system frame in a communication system.

[0029] Figure 6 is a conceptual diagram illustrating an embodiment of a subframe in a wireless communication system.

[0030] Figure 7 is a conceptual diagram illustrating an embodiment of a slot in a wireless communication system.

[0031] Figure 8 is a conceptual diagram illustrating an embodiment of time-frequency resources in a wireless communication system.

[0032] Figure 9 illustrates an example of a QCL relationship between reference signals applicable to the present disclosure.

[0033] FIG. 10 illustrates an example of a procedure for integrating and setting a beam for multiple channels or reference signals through a unified TCI state according to one embodiment of the present disclosure.

[0034] FIG. 11 illustrates an example of a setup procedure of each layer for transmitting a TCI state in an M-TRP structure according to one embodiment of the present disclosure.

[0035] FIG. 12 illustrates an example of a procedure for performing random access of a terminal according to one embodiment of the present disclosure.

[0036] FIG. 13 illustrates an example of a procedure for performing random access of a base station according to one embodiment of the present disclosure.

[0037] FIG. 14 illustrates a first example of a procedure for performing random access to an uplink (UL) transmission-reception point (TRP) according to one embodiment of the present disclosure.

[0038] FIG. 15 illustrates a second example of a procedure for performing random access to a UL TRP according to one embodiment of the present disclosure.

[0039] FIG. 16 illustrates a third example of a procedure for performing random access to a UL TRP according to one embodiment of the present disclosure.

[0040] FIG. 17 illustrates an example of a procedure for performing random access using beam sweeping according to one embodiment of the present disclosure.

[0041] FIG. 18 illustrates an example of the structure of a slot in which beam sweeping is performed according to one embodiment of the present disclosure.

[0042] FIG. 19 illustrates examples of random access occasions (RAOs) for random access according to one embodiment of the present disclosure.

[0043] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0044] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" may refer to a combination of multiple related items described herein or to any of multiple related items described herein.

[0045] In the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Additionally, in the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0046] In the present disclosure, (re)transmission may mean “transmission,” “retransmission,” or “transmission and retransmission,” (re)setting may mean “setting,” “resetting,” or “setting and resetting,” (re)connection may mean “connection,” “reconnection,” or “connection and reconnection,” and (re)connection may mean “connection,” “reconnection,” or “connection and reconnection.”

[0047] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0048] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0049] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0050] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted. In addition to the embodiments explicitly described in the present disclosure, operations may be performed according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments. The performance of some operations may be omitted, and the order of operation may be changed.

[0051] In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a corresponding second communication node can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a corresponding base station can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a corresponding UE can perform an operation corresponding to the operation of the base station.

[0052] A base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), a RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. A UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

[0053] In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message." A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message." A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message." Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and / or a radio resource control (RRC) message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

[0054] In the present disclosure, “an operation (e.g., a transmission operation) is set” may mean that “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing the performance of the operation” is signaled. “An information element (e.g., a parameter) is set” may mean that the information element is signaled. In the present disclosure, “a signal and / or a channel” may mean a signal, a channel, or “a signal and a channel,” and a signal may be used to mean “a signal and / or a channel.”

[0055] The communication networks to which the embodiments are applied are not limited to those described below, and the embodiments may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the term "communication network" may be used interchangeably with the term "communication system."

[0056] Figure 1 is a conceptual diagram illustrating an embodiment of a communication system.

[0057] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0058] A plurality of communication nodes (110 to 130) can support a communication protocol (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) specified in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0059] Figure 2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

[0060] FIG. 2 is a diagram illustrating an example of a wireless device (200) in a wireless communication system according to one embodiment of the present disclosure. The wireless device (200) according to the embodiment of the present disclosure may be a mobile terminal such as a smartphone, tablet PC, or wearable device, but is not limited thereto.

[0061] Referring to FIG. 2, the wireless device (200) may include at least one control unit (210), at least one memory (220), at least one power supply unit (230), at least one transceiver unit (240), at least one input unit (250), at least one output unit (260), and / or at least one antenna (270).

[0062] The control unit (210) can control the memory (220) and / or the transceiver unit (240), and can be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. The memory (220) can be connected to the control unit (210) and can store various information related to the operation of the control unit (210). For example, the memory (220) can perform some or all of the controls controlled by the control unit (210), or store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. The configuration of the memory is not limited in a specific manner. For example, it can be configured as at least one of a read-only memory (ROM) and a random access memory (RAM).

[0063] At least one control unit (210) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software in the form of codes, instructions, and / or a set of instructions. Here, the firmware or software may execute another program stored in a memory (220), such as an OS. The control unit (210) may be implemented to support beamforming or directional routing operations in which signals from at least one antenna (270) are weighted differently to effectively steer signals outgoing in a desired direction.

[0064] Additionally, at least one control unit (210) may be coupled to a backhaul or network interface. The wireless device (200) may communicate with other wireless devices through the backhaul or network interface. The control unit (210) may include at least one processor. The processor may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present disclosure are performed.

[0065] At least one transceiver (240) may be connected to the control unit (210) and may transmit and / or receive a wireless signal via at least one antenna (270). The transceiver (240) may include a transmitter and / or a receiver. The at least one transceiver (240) may transmit user data, control information, wireless signals / channels, etc. mentioned in the methods and / or operation flowcharts of the present disclosure to at least one other device. For example, the at least one transceiver (240) may be connected to at least one control unit (210) and may transmit and receive wireless signals. In addition, the at least one control unit (210) may control the at least one transceiver (240) to transmit user data, control information, or a wireless signal to at least one other device. The at least one transmitter (240) may receive a signal transmitted by another wireless device from at least one antenna (270). Additionally, at least one transceiver (24) may downconvert or upconvert the received signal to generate a baseband signal. At least one antenna (270) may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

[0066] The input unit (250) can obtain information such as user input, video, and audio, and can include various input means such as various mechanical / electronic input means, cameras, and microphones. The output unit (260) is for providing information to users by generating output related to sight, hearing, or touch, and can include a display, a speaker, a vibration module, and the like. The wireless device (200) supplies power through the power supply unit (230), and the power supply unit (230) can include a wired / wireless charging circuit, a battery, and the like.

[0067] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

[0068] Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

[0069] Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on board unit (OBU), etc.

[0070] Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to the core network via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

[0071] Additionally, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., device to device communication (D2D), proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) based on the MU-MIMO method.

[0072] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication under the control of the second base station (110-2) and the third base station (110-3), respectively.

[0073] Meanwhile, communication nodes performing communication in a communication network may be configured as follows. The communication node illustrated in FIG. 3 may be a specific embodiment of the wireless device illustrated in FIG. 2.

[0074] Figure 3 is a block diagram illustrating an embodiment of wireless devices performing communication.

[0075] Referring to FIG. 3, each of the first wireless device (300a) and the second wireless device (300b) may be a base station or a UE. The first wireless device (300a) may transmit a signal to the second wireless device (300b). The transmission processor (311) included in the first wireless device (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from the controller (316). The control information may include at least one of system information, RRC configuration information (e.g., information set by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0076] The transmitting processor (311) may perform a processing operation on data (e.g., an encoding operation, a symbol mapping operation, etc.) to generate data symbol(s). The transmitting processor (311) may perform a processing operation on control information (e.g., an encoding operation, a symbol mapping operation, etc.) to generate control symbol(s). In addition, the transmitting processor (311) may generate synchronization / reference symbol(s) for a synchronization signal and / or a reference signal.

[0077] The Tx MIMO processor (312) may perform a spatial processing operation (e.g., a precoding operation) on data symbol(s), control symbol(s), and / or synchronization / reference symbol(s). The output (e.g., a symbol stream) of the Tx MIMO processor (312) may be provided to modulators (MODs) included in the transceivers (313a to 313t). The modulators (MODs) may perform a processing operation on the symbol stream to generate modulation symbols, and may perform an additional processing operation (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) may be transmitted via the antennas (314a to 314t).

[0078] Signals transmitted by the first wireless device (300a) may be received by the antennas (364a to 364r) of the second wireless device (300b). The signals received by the antennas (364a to 364r) may be provided to demodulators (DEMODs) included in the transceivers (363a to 363r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (362) may perform a MIMO detection operation on the symbols. The receiving processor (361) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (361) may be provided to a data sink (360) and a controller (366). For example, data may be provided to the data sink (360), and control information may be provided to the controller (366).

[0079] Meanwhile, the second wireless device (300b) can transmit a signal to the first wireless device (300a). The transmitting processor (368) included in the second wireless device (300b) can receive data (e.g., data units) from a data source (367) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (368) can receive control information from the controller (366) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (368) can perform a processing operation on a reference signal to generate reference symbol(s).

[0080] The Tx MIMO processor (369) may perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or reference symbol(s). The output (e.g., symbol stream) of the Tx MIMO processor (369) may be provided to modulators (MODs) included in the transceivers (363a to 363t). The modulators (MODs) may perform processing operations on the symbol streams to generate modulation symbols, and may perform additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, upconversion operations) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) may be transmitted via the antennas (364a to 364t).

[0081] The signals transmitted by the second wireless device (300b) may be received by the antennas (314a to 314r) of the first wireless device (300a). The signals received by the antennas (314a to 314r) may be provided to the demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (320) may perform a MIMO detection operation on the symbols. The receiving processor (319) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (319) may be provided to a data sink (318) and a controller (316). For example, data may be provided to the data sink (318) and control information may be provided to the controller (316).

[0082] Memories (315 and 365) can store data, control information, and / or program code. Scheduler (317) can perform scheduling operations for communication. The processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) illustrated in FIG. 3 may be the processor (210) illustrated in FIG. 2 and may be used to perform the methods described in the present disclosure.

[0083] Fig. 4a is a block diagram illustrating an embodiment of a transmission path, and Fig. 4b is a block diagram illustrating an embodiment of a reception path.

[0084] Referring to FIGS. 4A and 4B, a transmission path (410) may be implemented in a communication node that transmits a signal, and a reception path (420) may be implemented in a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The receiving path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N may be a natural number.

[0085] In the transmission path (410), information bits may be input to a channel coding and modulation block (411). The channel coding and modulation block (411) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. The output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

[0086] The S-to-P block (412) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (413) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (414) can convert the output (e.g., parallel signals) of the N IFFT block (413) into a serial signal to generate a serial signal.

[0087] The CP addition block (415) can insert a CP into a signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered at the baseband before up-conversion.

[0088] A signal transmitted from a transmission path (410) may be input to a reception path (420). An operation in the reception path (420) may be the reverse operation of the operation in the transmission path (410). A DC (421) may down-convert the frequency of the received signal to a baseband frequency. A CP removal block (422) may remove a CP from a signal. The output of the CP removal block (422) may be a serial signal. An S-to-P block (423) may convert the serial signal into parallel signals. An N FFT block (424) may perform an FFT algorithm to generate N parallel signals. A P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. A channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

[0089] In FIGS. 4A and 4B , Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) may be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 4A and 4B may be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 4A and 4B may be implemented by software, and the remaining blocks may be implemented by hardware or a “combination of hardware and software.” In FIGS. 4A and 4B , a block may be subdivided into multiple blocks, multiple blocks may be integrated into a single block, some blocks may be omitted, and blocks supporting other functions may be added.

[0090] Figure 5 is a conceptual diagram illustrating an embodiment of a system frame in a communication system.

[0091] Referring to FIG. 5, time resources in a communication system can be divided into frame units. For example, system frames can be set consecutively in the time domain of the communication system. The length of a system frame can be 10 ms (milliseconds). The system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of the system frame after system frame #1023 can be #0.

[0092] A system frame may include two half frames. A half frame may be 5 ms long. A half frame located at the beginning of the system frame may be referred to as "half frame #0," and a half frame located at the end of the system frame may be referred to as "half frame #1." A system frame may include 10 subframes. A subframe may be 1 ms long. The 10 subframes within a system frame may be referred to as "subframes #0-9."

[0093] Figure 6 is a conceptual diagram illustrating an embodiment of a subframe in a communication system.

[0094] Referring to FIG. 6, one subframe may include n slots, where n may be a natural number. Accordingly, one subframe may be composed of one or more slots.

[0095] Figure 7 is a conceptual diagram illustrating an embodiment of a slot in a communication system.

[0096] Referring to Figure 7, a single slot may include one or more symbols. A single slot illustrated in Figure 7 may include 14 symbols. The length of a slot may vary depending on the number and length of symbols contained in the slot. Alternatively, the length of a slot may vary depending on the numerology.

[0097] In a communication system, the numerology applied to physical signals and channels may be variable. The numerology may be variable to meet various technical requirements of the communication system. In a communication system applying CP (cyclic prefix)-based OFDM waveform technology, the numerology may include subcarrier spacing and CP length (or CP type). Table 1 may be an embodiment of a method for configuring a numerology for a CP-OFDM-based communication system. At least some of the numerologies in Table 1 may be supported depending on the frequency band in which the communication system operates. In addition, the communication system may additionally support numerologies not listed in [Table 1].

[0098] Subcarrier spacing 15 ㎑ 30 ㎑ 60 ㎑ 120 ㎑ 240 ㎑ 480 ㎑ OFDM symbol length [㎲] 66.733.316.78.34.22.1 CP length [㎲] 4.762.381.190.600.300.151 Number of OFDM symbols in ㎳ 142856112224448

[0099] When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length can be 1 ms. In this case, one system frame can contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length can be 0.5 ms. In this case, one system frame can contain 20 slots. When the subcarrier spacing is 60 kHz (e.g., μ=2), the slot length can be 0.25 ms. In this case, one system frame can contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the slot length can be 0.125 ms. In this case, one system frame can contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the slot length can be 0.0625 ms. In this case, one system frame can contain 160 slots.

[0100] A symbol may be configured as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot consisting of only DL symbols may be referred to as a "DL slot," a slot consisting of only FL symbols may be referred to as an "FL slot," and a slot consisting of only UL symbols may be referred to as a "UL slot."

[0101] The slot format can be semi-statically configured by higher layer signaling (e.g., RRC signaling). Information indicating the semi-static slot format can be included in the system information, and the semi-static slot format can be configured cell-specifically. In addition, the semi-static slot format can be additionally configured for each terminal through terminal-specific higher layer signaling (e.g., RRC signaling). The flexible symbol of the cell-specifically configured slot format can be overridden to a downlink symbol or an uplink symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in DCI). The semi-statically configured slot format can be overridden by a dynamically indicated slot format. For example, the semi-statically configured flexible symbol can be overridden to a downlink symbol or an uplink symbol by the SFI.

[0102] The reference signal may be a channel state information-reference signal (CSI-RS), a sounding reference signal (SRS), a demodulation-reference signal (DM-RS), a phase tracking-reference signal (PT-RS), etc. The channel may be a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), etc. In the present disclosure, the control channel may mean a PDCCH, a PUCCH, or a PSCCH, and the data channel may mean a PDSCH, a PUSCH, or a PSSCH.

[0103] Figure 8 is a conceptual diagram illustrating an embodiment of time-frequency resources in a communication system.

[0104] Referring to FIG. 8, a resource consisting of one symbol (e.g., an OFDM symbol) in the time domain and one subcarrier in the frequency domain may be defined as a "RE (resource element)". Resources consisting of one OFDM symbol in the time domain and K subcarriers in the frequency domain may be defined as a "REG (resource element group)". A REG may include K REs. A REG may be used as a basic unit for resource allocation in the frequency domain. K may be a natural number. For example, K may be 12. N may be a natural number. In the slot illustrated in FIG. 7, N may be 14. N OFDM symbols may be used as a basic unit for resource allocation in the time domain.

[0105] In the present disclosure, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system, CRB may mean RB that constitutes a set of consecutive RBs (e.g., a common RB grid) based on a reference frequency (e.g., point A). Carriers and / or bandwidth portions may be arranged on the common RB grid. That is, the carrier and / or bandwidth portions may be composed of CRB(s). RBs or CRBs that constitute the bandwidth portions may be referred to as PRBs, and within the bandwidth portions, the CRB index may be appropriately converted to the PRB index.

[0106] Downlink data can be transmitted via the PDSCH. The base station can transmit PDSCH configuration information (e.g., scheduling information) to the terminal via the PDCCH. The terminal can obtain the PDSCH configuration information by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the PDSCH configuration information can include the MCS (modulation coding scheme) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. The PDSCH can refer to a radio resource through which downlink data is transmitted and received. Alternatively, the PDSCH can refer to the downlink data itself. The PDCCH can refer to a radio resource through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH can refer to the downlink control information itself.

[0107] A terminal can perform a monitoring operation on the PDCCH to receive a PDSCH transmitted from a base station. The base station can inform the terminal of the configuration information for the PDCCH monitoring operation using a higher layer message (e.g., an RRC (radio resource control) message). The configuration information for the PDCCH monitoring operation can include CORESET (control resource set) information and search space information.

[0108] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH opportunity information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH opportunity may be a region where the PDCCH can exist. In other words, the PDCCH opportunity may be a region where DCI can be transmitted. The PDCCH opportunity may be referred to as a PDCCH candidate. The PDCCH opportunity information may include time resource information and frequency resource information of the PDCCH opportunity. In the time domain, the length of the PDCCH opportunity may be indicated in symbol units. In the frequency domain, the size of the PDCCH opportunity may be indicated in RB units (e.g., in PRB (physical resource block) units or CRB (common resource block) units).

[0109] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. The period and offset of PDCCH monitoring may each be indicated on a slot-by-slot basis. In addition, the search space information may further include an index of the symbol at which the PDCCH monitoring operation begins.

[0110] A base station can configure a bandwidth part (BWP) for downlink communication. The BWP can be configured differently for each terminal. The base station can inform the terminal of the BWP configuration information using higher layer signaling. The higher layer signaling can mean "transmission operation of system information" and / or "transmission operation of RRC (radio resource control) message." The number of BWPs configured for one terminal can be one or more. The terminal can receive BWP configuration information from the base station and check the BWP(s) configured by the base station based on the BWP configuration information. When multiple BWPs are configured for downlink communication, the base station can activate one or more BWPs among the multiple BWPs. The base station can transmit the configuration information of the activated BWP(s) to the terminal using at least one of higher layer signaling, a medium access control (MAC) control element (CE), or DCI. The base station can perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and perform a downlink reception operation in the activated BWP(s).

[0111] Multiple Transmission and Reception Point (MTRP) technology refers to a technique in which a base station (e.g., gNB) communicates with a terminal by utilizing multiple transmission reception points (TRPs) that are physically separated. By utilizing multiple TRPs, MTRP technology can solve the problem of reduced quality-of-service (QoS) for terminals located at the cell edge when they are far from the base station, while also resolving the problem of inter-cell interference from base stations located in different cells. Furthermore, MTRP technology can play a role in providing an additional communication path, that is, a non-line-of-sight (NLOS) path, from the base station in cases where the line-of-sight (LOS) path from the base station is limited, such as in millimeter wave bands.

[0112] In the standard, MTRP technology is divided into Coherent Joint Transmission (CJT) and Non-Coherent Joint Transmission (NCJT). The CJT method allows two or more TRPs to cooperate in a synchronized manner to support data transmission to a single terminal based on a stable backhaul link between base stations connected to the TRPs. On the other hand, the NCJT method allows two or more TRPs to decide scheduling, precoding matrix selection, modulation, and coding schemes without cooperation between the TRPs in a situation where two or more TRPs support a single terminal.

[0113] Beam management for TRP in 5G NR can be defined as a set of L1 / L2 procedures that find or maintain the optimal beam required for transmission / reception at each TRP and terminal. Beam management procedures can be broadly categorized into four categories, as follows:

[0114] 1) Beam determination

[0115] 2) Beam measurement

[0116] 3) Beam reporting

[0117] 4) Beam sweeping

[0118] Here, the TRP and the UE can utilize the reciprocity characteristics of the downlink (DL) / uplink (UL) channels when managing beams. For example, the UE can utilize the values ​​measured in the receive beams (Rx beams) of the DL channel when configuring the transmit beam (Tx beam). And, the UE can utilize the values ​​measured in the transmit beams (Tx beams) of the UL channel when configuring the receive beam (Rx beam). These transmit beam configuration and receive beam configuration procedures can be performed in the same manner for the base station as for the UE. In particular, a transmission configuration indicator (TCI) has been introduced for beam management related to analog beamforming. The TCI can be used to configure a beam to be used for transmission of a specific channel and / or signal, for example, PDSCH and / or CSI-RS and / or PDCCH. The base station can dynamically indicate quasi-colocation (QCL) information to the UE by transmitting TCI through downlink control information (DCI).

[0119] Two antenna ports are said to be quasi-co-located when the channel characteristics of a symbol transmitted from one antenna port can be inferred from the channel characteristics of a symbol transmitted from the other antenna port. For convenience of explanation, in the following, when two antenna ports are quasi-co-located, we refer to them as having a QCL relationship.

[0120] Figure 9 illustrates an example of a QCL relationship between reference signals applicable to the present disclosure.

[0121] Referring to Fig. 9, the QCL relationship between reference signals below 5G can be extended to generate information about the TCI state.

[0122] The synchronization signal block (SSB) can be used by terminals to synchronize with the network and acquire basic information. The SSB can be in a QCL relationship with the tracking reference signal (TRS). Therefore, when receiving the TRS, at least one of the Doppler shift, delay average, and spatial characteristics of the SSB can be utilized.

[0123] CSI-RS (channel state information - reference signal): CSI-RS can be used by the network to determine the characteristics of the wireless channel. There are two types of CSI-RS. CSI-RS (CSI ACQ) can be used for CSI reception, and CSI-RS (BM) can be used for beam management (BM).

[0124] SSB and CSI-RS (BM) may be in a QCL relationship with CSI-RS (CSI ACQ), and at least one of the average and spatial characteristics of Doppler shift and delay may be utilized for CSI-RS (CSI ACQ) reception.

[0125] CSI-RS(BM) and SSB may have a QCL relationship with PDCCH DMRS (physical downlink control channel demodulation reference signal), and at least one of Doppler shift / spread and average / spread and spatial characteristics of delay may be utilized for reception of PDCCH DMRS.

[0126] SSB, CSI-RS (BM) and CSI-RS (CSI ACQ) may be in a QCL relationship with PDSCH DMRS, and at least one of the mean / spread and spatial characteristics of Doppler shift / spread and delay may be utilized for reception of PDCCH DMRS.

[0127] 3GGP Rel-17 introduced a TCI configuration method utilizing a unified TCI pool, or the unified TCI framework, to reduce signaling overhead for QCL configuration of DL and / or UL channels and simplify multi-beam operation compared to the previous release of 3GGP Rel-16.

[0128] According to the unified TCI framework, the base station can preset a common TCI pool that can be commonly used (or applied) to DL and UL channels via RRC signaling. Furthermore, according to the unified TCI framework, the base station can directly indicate TCI for DL ​​and UL channels from the configured common TCI pool using the Medium Access Control (MAC) control element (CE) (MAC-CE) / downlink control information (DCI). Furthermore, according to the unified TCI framework, the base station can support updates to the common TCI state.

[0129] A common TCI state can be indicated (or set) for multiple component carriers (CCs). Among the multiple CCs, a reference CC can be additionally set, and TCI updates for other CCs within the indicated list can be performed simultaneously via a TCI update command for the reference CC.

[0130] At this time, there are three main methods for setting the status of TCI for DL ​​channels and UL channels.

[0131] A. Joint TCI state indication method that is commonly indicated to DL / UL channels

[0132] B. DL channel separate TCI state indication method for setting TCI separately for DL ​​channel and

[0133] C. UL Channel Separate TCI State Indication Method

[0134] Looking at the three methods above from a broader perspective, they can be divided into a joint TCI status indication method that provides common indications for both DL and UL channels, and a separate TCI status indication method that sets TCIs separately for each DL or UL channel. The fundamental difference between the two methods above lies in the existence of reciprocity between the DL and UL channels.

[0135] The Unified TCI framework was designed for a single TRP (sTRP) system in 3GPP Rel-17. However, 3GPP Rel-18 aims to expand to a multi-TRP (mTRP) system.

[0136] TCI status can be used to convey QCL relationships to terminals. TCI status contains information about QCL relationships and can be conveyed via DCI. Section 5.1.5 of 3GPP TS 38.214 defines the procedure for conveying QCL information as follows:

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150] As above, the UE can be configured with TCI-State configuration lists through higher layer parameters (e.g., PDSCH-Config). The UE can decode the PDSCH using the TCI-State configuration lists. Each TCI state can include parameters that configure the QCL relationship between one or two downlink reference signals and the DM-RS port of the PDSCH, the DM-RS port of the PDCCH, or the CSI-RS port(s) of the CSI-RS resource. The QCL can be configured for the first DL RS using the higher layer parameter qcl-Type1, and for the second DL RS using qcl-Type2. The QCL types of the two DL RSs can be configured differently regardless of whether they are DL RSs with the same reference or different DL RSs. The QCL type corresponding to each DL RS can be configured by the higher layer parameter (e.g., qcl-Type in QCL-Info). The QCL type can have one of the following values:

[0151] - typeA: {Doppler shift, Doppler spread, average delay, delay spread}

[0152] - typeB: {Doppler shift, Doppler spread}

[0153] - typeC: {Doppler shift, average delay}

[0154] - typeD: {Spatial Rx parameter}

[0155] Here, the Spatial RX parameter can refer to any one of various parameters, such as Angle of arrival (AoA), Power Angular Spectrum (PAS) of AoA, Angle of departure (AoD), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, and spatial channel correlation.

[0156] The base station can transmit configuration information regarding whether to apply information in the transmission configuration indication (TCI) field included in the downlink control information (DCI) to the terminal through upper layer signaling.

[0157] Additionally, the terminal may receive information regarding TCI states or TCI state pairs. For example, the base station may transmit multiple TCI states to the terminal via RRC signaling, and may set some of them as TCI states for CORESET. The terminal may receive an activation command. The activation command may be used to map TCI state(s) and / or TCI state pair(s) to codepoints in the DCI field 'transmission configuration indication'.

[0158] Additionally, as shown in FIG. 10 below, it can be set to set a beam by integrating multiple channels or reference signals through a unified TCI state.

[0159] Instead of transmitting the TCI state for each channel to the UE, the base station can transmit information about beam settings for CSI-RS, CORESET, PDSCH, PUSCH, PUCCH, SRS, etc. to the UE through the unified TCI state. Whether the unified TCI state is activated or not can be explicitly or implicitly transmitted to the UE. For example, if the BWP of the CC does not have a TCI-State or TCI-UL-State configuration, the UE can apply the TCI-State or TCI-UL-State configuration from the reference BWP of the reference CC configured by the unified TCI-StateRef.

[0160] A multiple transmission and reception point (M-TRP) technique can be proposed, in which communication is performed through multiple transmitting and receiving nodes. The M-TRP technique can be divided into a single control information technique (single downlink control information (S-DCI)) that controls transmission and reception through multiple nodes through a single control information, and a multiple downlink control information technique (multiple downlink control information (M-DCI)) that separately transmits information for each node. In addition, the procedure for transmitting TCI information may vary depending on whether TCI information for uplink and downlink is set separately or jointly.

[0161] FIG. 11 illustrates an example of a setup procedure of each layer for transmitting a TCI state in an M-TRP structure according to one embodiment of the present disclosure.

[0162] First, there are two types of configurations related to TCI: separate and joint. In the separate type, the TCI state is set through separate TCI state lists for uplink and downlink, respectively, while in the joint type, the TCI state is set through joint TCI state lists for uplink and downlink. The base station can convey the configuration type related to the unified TCI to the terminal through unifiedTCI-StateType in ServingCellConfig. In addition, the base station can convey information about the resource set for the reference signal to the terminal through PDSCH-Config, and PDSCH-Config can be included in the BWP-Downlink IE.

[0163] Additionally, the terminal can be configured with a list of up to 128 TCI state configurations via upper layer parameters (e.g., dl-OrJointTCI-StateList in PDSCH-Config). The TCI configuration list can be used to provide criteria for determining ULTX spatial filters for dynamic-grant and configured-grant based PUSCH and PUCCH resources and SRS in BWP / CC.

[0164] Among the TCI state settings, the TCI state settings that are activated can be transmitted through the TCI state enable / disable MAC CE. The integrated TCI state enable / disable MAC CE can be defined as follows.

[0165]

[0166]

[0167] The integrated TCI state enable / disable MAC CE can indicate the TCI state ID to be enabled. The integrated TCI state enable / disable MAC CE includes a serving cell ID, a DL BWP ID, and an UL BWP ID. It can indicate a serving cell and a BWP to which the MAC CE can be applied as a code point. The Pi field can indicate whether each ith code point includes multiple TCI states or a single TCI state. If Pi = 1, the ith TCI code point includes multiple TCI states, and if Pi = 0, the ith TCI code point can include only a DL / joint TCI state or only a UL TCI state.

[0168] The D / U field can indicate whether the TCI state corresponding to the TCI state ID existing in the same octet is a DL / joint TCI state or an UL TCI state. Therefore, in FIG. 11, the D / U field belonging to the same octet as a separate type of DL TCI state and a joint type of TCI state can be set to 1, and the D / U field belonging to the same octet as a separate type of UL TCI state can be set to 0.

[0169] An enhanced integrated TCI state enable / disable MAC CE for joint TCI states can be defined as follows.

[0170]

[0171]

[0172] Unlike the integrated TCI state enable / disable MAC CE, the enhanced integrated TCI state enable / disable MAC CE for joint TCI states can jointly manage the TCI states of uplink and downlink, so the UL BWP ID can be omitted. The Fi,j field indicates whether the jth joint TCI state exists in the TCI state ID field associated with code point i of the DCI Transmission Configuration Indication field. Here, j can have the value 1 or 2. Therefore, in the case of the joint type as in step#2 of FIG. 11, up to two joint TCI states can correspond to each code point, and up to 16 joint TCI states can be activated.

[0173] An enhanced unified TCI state enable / disable MAC CE for separate TCI states can be defined as follows.

[0174]

[0175]

[0176] Unlike the unified TCI state enable / disable MAC CE, the enhanced unified TCI state enable / disable MAC CE for separate TCI states may include an Fi,j field and a Si,j field. The Fi,j field indicates whether the jth DL TCI state exists in the TCI state ID field associated with the code point i of the DCI Transmission Configuration Indication field. The Si,j field indicates whether the jth UL TCI state exists in the TCI state ID field associated with the code point i of the DCI Transmission Configuration Indication field. Therefore, in the case of the separate type of step#2 of FIG. 11, since each code point can correspond to at most two DL TCI states and at most two UL TCI states, a maximum of 32 TCI states can be enabled.

[0177] A base station can transmit DCI to a terminal via a PDCCH. The DCI can include a transmission configuration indication field, and decoding can be performed using the TCI state corresponding to the code point i in the transmission configuration indication field included in the DCI. As described above, the correspondence between the code point i and the TCI state can be indicated by a TCI state activation command.

[0178] The terminal can use the TCI state as follows using the received DCI.

[0179]

[0180]

[0181] That is, when the terminal receives a single TCI state for a CORESET, or receives a MAC CE activation command for one or two of the TCI states provided for the CORSET, the terminal may assume that the DM-RS antenna ports associated with the PDCCH receptions within the CORESET are in a QCL relationship with one or more DL RSs established by the TCI states.

[0182] A TCI state can be indicated by splitting it into two states. For example, if the terminal is provided with dl-OrJointTCI-StateList, the TCI states can be indicated through a combination of two TCI states (the first TCI state, the second TCI state, the first TCI state and the second TCI state, none). For example, if the terminal indicates the first TCI state through apply-IndicatedTCISate, the terminal can assume that the reference signal provided by the first TCI state and the DM-RS antenna port for PDCCH reception are in a QCL relationship.

[0183] If dl-OrJointTCI-StateList is provided to the UE and coresetPoolIndex is not provided to the UE or coresetPoolIndex is provided with 0 for the first coreset in the active DL BWP of the serving cell, the UE may assume that the DM-RS antenna ports for PDCCH reception in the first and second coresets and the DM-RS antenna ports for PDSCH reception scheduled by the DCI formats provided by PDCCH reception in the first and second coresets are in a QCL relationship with the reference signals provided by the TCI states specific to the first and second CORESETs, respectively. Furthermore, the UE may transmit the PUSCH scheduled by the DCI formats provided by PDCCH reception in the first and second CORESETs, respectively, using the spatial domain filters corresponding to the TCI states specific to the first and second CORESETs, respectively.

[0184] The TCI state can be used to transmit uplink signals. The terminal can use the following procedures to control uplink power.

[0185]

[0186]

[0187] Uplink power control can be used to determine power for PUSCH, PUCCH, SRS, or PRACH transmissions. The UE may be configured not to maintain more than four path loss estimates simultaneously for PUSCH / PUCCH / SRS transmissions per serving cell.

[0188] For PUSCH, PUCCH, SRS, or PRACH transmissions, a transmission opportunity can be defined by a slot index within a frame, the first symbol within the slot, and the number of consecutive symbols. If the UE receives TCI states in dl-OrJointTCI-StateList, an RS index for downlink path loss estimation for PUSCH, PUCCH, or SRS transmission can be provided for each one or both TCI states for PUSCH, PUCCH, or SRS transmission opportunities.

[0189] Power control values ​​can be set explicitly or implicitly. For example, if followUnifiedTCI-StateSRS is set, power control values ​​are provided from p0AlphaSetforSRS associated with the TCI state. If followUnifiedTCI-StateSRS is not set, power control values ​​and an RS index for path loss estimation can be provided from the TCI state associated with the SRS resource with the lowest SRS-ResourceId. In this case, the overall SRS power value can be determined based on the sum of individual SRS power control values ​​and additional components according to the SRS resource set.

[0190] Hereinafter, the initial connection procedure between a terminal and a base station will be described. If the initial connection procedure is performed with the base station due to reasons such as the terminal's power on / off operation or loss of coverage, an identification procedure between the base station and the terminal may be required. First, the terminal may perform an initial cell search operation with the base station. The terminal may perform monitoring to receive a synchronization signal. The synchronization signal may be at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The terminal may receive a physical broadcast channel (PBCH) signal from the base station to obtain broadcast information within the cell. Based on the physical broadcast channel, the terminal may obtain information about the cell using at least one of the MIB or SIB. A block including all of the PSS, SSS, and PBCH may be referred to as a synchronization signal block (SSB).

[0191] A terminal can perform a random access procedure. The terminal can transmit a preamble to the base station and receive a random access response (RAR) from the base station. The RAR message can include a temporary identifier. The terminal can transmit MSG3 (or an RRC connection request message) using the scheduling information in the RAR, and the base station can perform a contention resolution procedure by transmitting MSG4 (or a contention resolution message) to the terminal in response to MSG3.

[0192] The base station can perform beam management based on the RACH opportunity used for preamble transmission in the random access procedure. For example, the base station can determine the beam on which the terminal received the synchronization signal based on the RACH opportunity in which the preamble was transmitted. As described above, a synchronization signal can also be included as a reference signal for indicating the QCL relationship, and the QCL relationship can be established based on the SSB received through the initial access procedure.

[0193] Additionally, a channel measurement procedure may be performed for beam management. The terminal may receive a reference signal from the base station. Based on this, the terminal may report channel state information (CSI) to the base station. The channel state information may include at least one of reference signal received power (RSRP), reference signal received quality (RSRQ), and signal-to-noise ratio (SNR). The base station may use the received channel state information to adjust beamforming for the terminal or optimize radio resource allocation. For channel measurement, the base station may transmit configuration information for channel measurement to the terminal. The configuration information for channel measurement may include information related to a measurement target, a measurement cycle, and the like.

[0194] Base station and terminal beam settings can be managed through artificial intelligence (AI). For convenience, beam set B refers to the beam set where measurements are performed using AI / ML model input, and beam set A refers to the beam set determined based on AI / ML model inference. Beam sets A and B may contain beam information for the same frequency range.

[0195] Artificial intelligence can be used to infer spatial domain downlink beams for beam set A based on measurements of beam set B. As another example, artificial intelligence can be used to infer temporal downlink beams for beam set A based on past measurements of beam set B. Here, beam set A and beam set B may be different sets, or beam set B may be a subset of beam set A.

[0196] Additionally, the input of the artificial intelligence model can be formed from various combinations. For example, the input of the artificial intelligence can include at least one of an L1-RSRP measurement based on beam set B, other auxiliary information, a channel impulse response (CIR) based on beam set B, and a downlink Tx / Rx beam ID associated with the L1-RSRP measurement of beam set B.

[0197] The aforementioned artificial intelligence model can be designed to infer a beam including at least one of a downlink reception beam and a downlink transmission beam. In addition, the output of the artificial intelligence model can include at least one of a transmission beam, a reception beam, an L1-RSRP of the transmission beam, an L1-RSRP of the reception beam, an angle of the transmission beam, an angle of the reception beam, and other information.

[0198] The beam management method using an AI model is not limited to the aforementioned method. The AI ​​model can be configured in various ways by configuring inputs and outputs with various combinations of settings for beam sets A and B, performance monitoring, data collection, and auxiliary information.

[0199] Learning and inference methods can also be implemented in various ways. For example, artificial intelligence can be learned or trained using an AI / ML (artificial intelligence / machine learning) model. Learning and training can be performed by the network or the UE. Furthermore, learning and inference can be performed on different devices. For example, learning can be performed on the network and inference on the UE. Split learning can be performed in such a way that some of the learning is performed on a first device and some on a second device. Similarly to learning, split inference can be performed using multiple devices. Input data for inference can also be generated in various ways. For example, input data can be generated on the UE, and inference can be performed using the input data on the network. Furthermore, input data generated on the UE can be used for inference within the UE.

[0200]

[0201] The DL sTRP (single TRP) / UL mTRP (multiple TRP) scenario is a single DCI-based mTRP communication method based on the UL standard. In addition to the TRP capable of both DL and UL communication, it requires reception of signals such as SSB for the initial connection process to acquire synchronization with the TRP that only performs UL communication, UL TA (timing advanced), beam alignment, and path loss. However, in a situation where the UE does not have a DL signal that can be received through the TRP that only performs UL communication, an connection method for operating the DL sTRP / UL mTRP scenario is required. Therefore, the present disclosure proposes a technology for connection between the UE and the TRP to enable the operation of the DL sTRP / UL mTRP scenario.

[0202]

[0203] Before describing the embodiments of the present disclosure, the following are the matters under discussion in standardization.

[0204] For asymmetric DL sTRP / UL mTRP deployment scenarios, support is provided to associate a UL TCI state with a PL offset.

[0205] - When a UL TCI state associated with a PL offset is applied for the PUSCH / PUCCH / SRS transmission, the UE shall calculate the Tx power of the PUSCH / PUCCH / SRS based on the DL PL RS and PL offset associated with this UL TCI state.

[0206] o Reuse the legacy uplink power control formulation by replacing legacy PL with UL PL derived from the DL PL RS and the PL offset.

[0207] o FFS (for further study): The UE can update the UL PL in a way that new UL PL = current UL PL + an update delta indicated by the NW.

[0208] - Note: It does not intend to increase the number of maintained PLs per cell.

[0209] · FFS: whether to support associating joint TCI state (if supported) with a PL offset

[0210] Further study whether / how to apply a PL offset on PDCCH-order PRACH transmission too.

[0211] · FFS: How to determine the Tx beam of PRACH towards UL TRP

[0212] · Note: This does not imply support 2 TA for single-DCI based system.

[0213]

[0214] Looking at the DCI format 1_0 used as the PDCCH order in the TS 38.212 standard document, it is as follows [Table 8].

[0215] DCI format 1_0 is used for the scheduling of PDSCH in one DL cell.The following information is transmitted by means of the DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI:- Identifier for DCI formats - 1 bits- The value of this bit field is always set to 1, indicating a DL DCI format- Frequency domain resource assignment - bits where is given by Clause 7.3.1.0If the CRC of the DCI format 1_0 is scrambled by C-RNTI and the "Frequency domain resource assignment" field are of all ones, the DCI format 1_0 is for random access procedure initiated by a PDCCH order, with all remaining fields set as follows:- Random Access Preamble index - 6 bits according to ra-PreambleIndex in Clause 5.1.2 of [8, TS38.321]- UL / SUL indicator - 1 bit. If the value of the "Random Access Preamble index" is not all zeros and if the UE is configured withsupplementaryUplinkinServingCellConfigin the cell, this field indicates which UL carrier in the cell to transmit the PRACH according to Table 7.3.1.1.1-1; otherwise, this field is reserved- SS / PBCH index - 6 bits. If the value of the "Random Access Preamble index" is not all zeros, this field indicates the SS / PBCH that shall be used to determine the RACH occasion for the PRACH transmission; otherwise, this field is reserved.- PRACH Mask index - 4 bits.If the value of the "Random Access Preamble index" is not all zeros, this field indicates the RACH occasion associated with the SS / PBCH indicated by "SS / PBCH index" for the PRACH transmission, according to Clause 5.1.1 of [8, TS38.321]; otherwise, this field is reserved- Cell indicator -. bits indicating the cell for the corresponding PRACH transmission if the UE is configured with higher layer parameterEarlyUlSyncConfig, where C is the number of candidate cells configured with higher layer parameterEarlyUlSyncConfig; 0 bit otherwise. The bit field index 0 of the cell indicator field is mapped to the serving cell, and other bit field indexes are mapped to the candidate cells configured with higher layer parameterEarlyUlSyncConfigaccording to an ascending order of a candidate identity configured byltm-CandidateId, with the bit field index 1 mapped to the candidate cell with the smallest candidate identity.- PRACH association indicator - 0 or 1 bit- 1bit if the UE is provided withtag-Id2, and the UE is not providedcoresetPoolIndexor is providedcoresetPoolIndexwith value 0 for the first CORESETs, and is providedcoresetPoolIndexwith value 1 for the second CORESETs.- This field indicates the PCI associated with the PRACH transmission if the UE is providedSSB-MTC-AddtionalPCI. The bit field index 0 of this field is mapped to the PCI of the serving cell, and the bit field index 1 of this field is mapped to the active additional PCI.- This field indicates the PL-RS for the PRACH transmission if the UE is not providedSSB-MTC-AddtionalPCI. The bit field index 0 of this field is mapped to the DL RS that the DM-RS of the PDCCH order is quasi-collocated with, and the bit field index 1 of this field is mapped to the SS / PBCH indicated by the SS / PBCH index field in this DCI format.- 0 bit otherwise.- PRACH retransmission indicator - 0 or 1 bit- 1bit if the UE is configured with higher layer parameterEarlyUlSyncConfig. This field indicates initial transmission or retransmission of PRACH according to Table 7.3.1.2.1-3 if the cell indicated by Cell indicator field is a candidate cell, and this field is reserved if the cell indicated by Cell indicator field is a serving cell but not a candidate cell.- 0 bit otherwise.

[0216] In the TS 38.321 standard document, the PRACH mask index is defined as shown in [Table 9] below.

[0217] PRACH Mask Index / msgA-SSB-SharedRO-MaskIndex / ssb-SharedRO-MaskIndexlowed PRACH occasion(s) of SSB0All1PRACH occasion index 12PRACH occasion index 23PRACH occasion index 34PRACH occasion index 45PRACH occasion index 56PRACH occasion index 67PRACH occasion index 78PRACH occasion index 89Every even PRACH occasion10Every odd PRACH occasion11Reserved12Reserved13Reserved14Reserved15Reserved

[0218] In the TS 38.331 standard document, the RACH-configCommon IE (information element) for configuring PRACH is defined as shown in [Table 10] below.

[0219] RACH-ConfigCommon information element-- ASN1START-- TAG-RACH-CONFIGCOMMON-STARTRACH-ConfigCommon ::= SEQUENCE {rach-ConfigGeneric RACH-ConfigGeneric,totalNumberOfRA-Preambles INTEGER (1..63) OPTIONAL, -- Need Sssb-perRACH-OccasionAndCB-PreamblesPerSSB CHOICE {oneEighth ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},oneFourth ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},oneHalf ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},one ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},two ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32},four INTEGER (1..16),eight INTEGER (1..8),sixteen INTEGER (1..4)} OPTIONAL, -- Need MgroupBconfigured SEQUENCE {ra-Msg3SizeGroupA ENUMERATED {b56, b144, b208, b256, b282, b480, b640,b800, b1000, b72, spare6, spare5,spare4, spare3, spare2, spare1},messagePowerOffsetGroupB ENUMERATED { minusinfinity, dB0, dB5, dB8, dB10, dB12, dB15, dB18},numberOfRA-PreamblesGroupA INTEGER (1..64)} OPTIONAL, -- Need Rra-ContentionResolutionTimer ENUMERATED { sf8, sf16, sf24, sf32, sf40, sf48, sf56, sf64},rsrp-ThresholdSSB RSRP-Range OPTIONAL, -- Need Rrsrp-ThresholdSSB-SUL RSRP-Range OPTIONAL, -- Cond SULprach-RootSequenceIndex CHOICE {l839 INTEGER (0..837),l139 INTEGER (0..137)},msg1-SubcarrierSpacing SubcarrierSpacing OPTIONAL, -- Cond L139restrictedSetConfig ENUMERATED {unrestrictedSet, restrictedSetTypeA, restrictedSetTypeB},msg3-transformPrecoder ENUMERATED {enabled} OPTIONAL, -- Need R...,[[ra-PrioritizationForAccessIdentity-r16 SEQUENCE {ra-Prioritization-r16 RA-Prioritization,·ssb-perRACH-OccasionAndCB-PreamblesPerSSBThe meaning of this field is twofold: the CHOICE conveys the information about the number of SSBs per RACH occasion. Value oneEighth corresponds to one SSB associated with 8 RACH occasions, value oneFourth corresponds to one SSB associated with 4 RACH occasions, and so on. The ENUMERATED part indicates the number of Contention Based preambles per SSB. Value n4 corresponds to 4 Contention Based preambles per SSB, value n8 corresponds to 8 Contention Based preambles per SSB, and so on. The total number of CB preambles in a RACH occasion is given by CB-preambles-per-SSB * max(1, SSB-per-rach-occasion). See TS 38.213

[0013] .

[0220] TS 38.331 규격문서에서 PRACH에 대한 구성을 위한 RACH-ConfigCommonTwoStepRA IE는 이하 [표 11]과 같이 정의된다.

[0221] RACH-ConfigCommonTwoStepRA information element-- ASN1START-- TAG-RACH-CONFIGCOMMONTWOSTEPRA-STARTRACH-ConfigCommonTwoStepRA-r16 ::= SEQUENCE {rach-ConfigGenericTwoStepRA-r16 RACH-ConfigGenericTwoStepRA-r16,msgA-TotalNumberOfRA-Preambles-r16 INTEGER (1..63) OPTIONAL, -- Need SmsgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB-r16 CHOICE {oneEighth ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},oneFourth ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},oneHalf ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},one ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32,n36,n40,n44,n48,n52,n56,n60,n64},two ENUMERATED {n4,n8,n12,n16,n20,n24,n28,n32},four INTEGER (1..16),eight INTEGER (1..8),sixteen INTEGER (1..4)} OPTIONAL, -- Cond 2StepOnlymsgA-CB-PreamblesPerSSB-PerSharedRO-r16 INTEGER (1..60) OPTIONAL, -- Cond SharedROmsgA-SSB-SharedRO-MaskIndex-r16 INTEGER (1..15) OPTIONAL, -- Need SgroupB-ConfiguredTwoStepRA-r16 GroupB-ConfiguredTwoStepRA-r16 OPTIONAL, -- Need SmsgA-PRACH-RootSequenceIndex-r16 CHOICE {l839 INTEGER (0..837),l139 INTEGER (0..137),l571 INTEGER (0..569),l1151 INTEGER (0..1149)} OPTIONAL, -- Cond 2StepOnlymsgA-TransMax-r16 ENUMERATED {n1, n2, n4, n6, n8, n10, n20, n50, n100, n200} OPTIONAL, -- Need RmsgA-RSRP-Threshold-r16 RSRP-Range OPTIONAL, -- Cond 2Step4StepmsgA-RSRP-ThresholdSSB-r16 RSRP-Range OPTIONAL, -- Need RmsgA-SubcarrierSpacing-r16 SubcarrierSpacing OPTIONAL, -- Cond 2StepOnlyL139msgA-RestrictedSetConfig-r16 ENUMERATED {unrestrictedSet, restrictedSetTypeA,restrictedSetTypeB} OPTIONAL, -- Cond 2StepOnlyra-PrioritizationForAccessIdentityTwoStep-r16 SEQUENCE {ra-Prioritization-r16 RA-Prioritization,ra-PrioritizationForAI-r16 BIT STRING (SIZE (2))} OPTIONAL, -- Cond InitialBWP-Onlyra-ContentionResolutionTimer-r16 ENUMERATED {sf8, sf16, sf24, sf32, sf40, sf48, sf56, sf64} OPTIONAL, -- Cond 2StepOnly...,[[ra-PrioritizationForSlicingTwoStep-r17 RA-PrioritizationForSlicing-r17 OPTIONAL, -- Cond InitialBWP-Only.

[0222] In the TS 38.331 standard document, the RACH-ConfigDedicated IE for configuring PRACH is defined as shown in [Table 12] below.

[0223] RACH-ConfigDedicated information element-- ASN1START-- TAG-RACH-CONFIGDEDICATED-STARTRACH-ConfigDedicated ::= SEQUENCE {cfra CFRA OPTIONAL, -- Need Sra-Prioritization RA-Prioritization OPTIONAL, -- Need N...,[[ra-PrioritizationTwoStep-r16 RA-Prioritization OPTIONAL, -- Need Ncfra-TwoStep-r16 CFRA-TwoStep-r16 OPTIONAL -- Need S]]}CFRA ::= SEQUENCE {occasions SEQUENCE {rach-ConfigGeneric RACH-ConfigGeneric,ssb-perRACH-Occasion ENUMERATED {oneEighth, oneFourth, oneHalf, one, two, four, eight, sixteen}OPTIONAL -- Cond Mandatory} OPTIONAL, -- Need Sresources CHOICE {ssb SEQUENCE {ssb-ResourceList SEQUENCE (SIZE(1..maxRA-SSB-Resources)) OF CFRA-SSB-Resource,ra-ssb-OccasionMaskIndex INTEGER (0..15)},csirs SEQUENCE {csirs-ResourceList SEQUENCE (SIZE(1..maxRA-CSIRS-Resources)) OF CFRA-CSIRS-Resource,rsrp-ThresholdCSI-RS RSRP-Range}},...,[[totalNumberOfRA-Preambles INTEGER (1..63) OPTIONAL -- Cond Occasions]],[[msg1-RepetitionNum-r18 ENUMERATED {n2, n4, n8, spare1} OPTIONAL -- Cond 4StepCFRArep]]}CFRA-TwoStep-r16 ::= SEQUENCE {occasionsTwoStepRA-r16 SEQUENCE {rach-ConfigGenericTwoStepRA-r16 RACH-ConfigGenericTwoStepRA-r16,ssb-PerRACH-OccasionTwoStepRA-r16 ENUMERATED {oneEighth, oneFourth, oneHalf, one,two, four, eight, sixteen}} OPTIONAL, -- Need SmsgA-CFRA-PUSCH-r16 MsgA-PUSCH-Resource-r16,msgA-TransMax-r16 ENUMERATED {n1, n2, n4, n6, n8, n10, n20, n50, n100, n200} OPTIONAL, -- Need SresourcesTwoStep-r16 SEQUENCE {ssb-ResourceList SEQUENCE (SIZE(1..maxRA-SSB-Resources)) OF CFRA-SSB-Resource,ra-ssb-OccasionMaskIndex INTEGER (0..15)},...}CFRA-SSB-Resource ::= SEQUENCE {ssb SSB-Index,ra-PreambleIndex INTEGER (0..63),...,[[msgA-PUSCH-Resource-Index-r16 INTEGER (0..3071) OPTIONAL -- Cond 2StepCFRA]]}CFRA-CSIRS-Resource ::= SEQUENCE {csi-RS CSI-RS-Index,ra-OccasionList SEQUENCE (SIZE(1..maxRA-OccasionsPerCSIRS)) OF INTEGER (0..maxRA-Occasions-1),ra-PreambleIndex INTEGER (0..63),...}·csi-RSThe ID of a CSI-RS resource defined in the measurement object associated with this serving cell.·ra-OccasionListRA occasions that the UE shall use when performing CF-RA upon selecting the candidate beam identified by this CSI-RS. The network ensures that the RA occasion indexes provided herein are also configured by prach-ConfigurationIndex and msg1-FDM. Each RACH occasion is sequentially numbered, first, in increasing order of frequency resource indexes for frequency multiplexed PRACH occasions; second, in increasing order of time resource indexes for time multiplexed PRACH occasions within a PRACH slot and Third, in increasing order of indexes for PRACH slots.·ra-PreambleIndexThe RA preamble index to use in the RA occasions associated with this CSI-RS.·msg1-RepetitionNumIndicates the MSG1 repetition number used for contention free 4-step random access type in TS 38.321 [3].If this field is absent, the UE performs contention free 4-step random access without MSG1-Repetitions.·occasionsRA occasions for contention free random access. If the field is absent, the UE uses the RA occasions configured in RACH-ConfigCommon in the first active UL BWP.·ra-ssb-OccasionMaskIndexExplicitly signalled PRACH Mask Index for RA Resource selection in TS 38.321 [3]. The mask is valid for all SSB resources signalled in ssb-ResourceList.·rach-ConfigGenericConfiguration of contention free random access occasions for CFRA. The UE shall ignore preambleReceivedTargetPower, preambleTransMax, powerRampingStep, ra-ResponseWindow signaled within this field and use the corresponding values provided in RACH-ConfigCommon.·ssb-perRACH-OccasionNumber of SSBs per RACH occasion.·totalNumberOfRA-PreamblesTotal number of preambles used for contention free random access in the RACH resources defined in CFRA, excluding preambles used for other purposes (e.g. for SI request).If the field is absent but the field occasions is present, the UE may assume all the 64 preambles are for RA. The setting should be consistent with the setting of ssb-perRACH-Occasion, if present, i.e. it should be a multiple of the number of SSBs per RACH occasion.·msgA-PUSCH-Resource-IndexIdentifies the index of the PUSCH resource used for MSGA CFRA. The PUSCH resource index indicates a valid PUSCH occasion (as specified in TS 38.213

[0013] , clause 8.1A) and the associated DMRS resources corresponding to a PRACH slot.The PUSCH resource indexes are sequentially numbered and are mapped to valid PUSCH occasions corresponding to a PRACH slot which are ordered, first, in increasing order of frequency resource indexes for frequency multiplexed PUSCH occasions; second, in increasing order of DMRS resource indexes within a PUSCH occasion, where a DMR / mathbit{S}_{ / mathbit{id}} resource index is determined first in an ascending order of a DMRS port index and then in an ascending order of a DMRS sequence index, third in increasing order of time resource indexes for time multiplexed PUSCH occasions within a PUSCH slot and fourth, in increasing order of indexes for PUSCH slots. For the case of contention free 2-step random access type, if this field is absent, the UE shall use the value 0.·ra-PreambleIndexThe preamble index that the UE shall use when performing CF-RA upon selecting the candidate beams identified by this SSB.·ssbThe ID of an SSB transmitted by this serving cell.

[0224] In the TS 38.331 standard document, the RACH-ConfigGeneric IE for configuration of PRACH is defined as shown in [Table 13] below.

[0225] RACH-ConfigGeneric information element-- ASN1START-- TAG-RACH-CONFIGGENERIC-STARTRACH-ConfigGeneric ::= SEQUENCE {prach-ConfigurationIndex INTEGER (0..255),msg1-FDM ENUMERATED {one, two, four, eight},msg1-FrequencyStart INTEGER (0..maxNrofPhysicalResourceBlocks-1),zeroCorrelationZoneConfig INTEGER(0..15),preambleReceivedTargetPower INTEGER (-202..-60),preambleTransMax ENUMERATED {n3, n4, n5, n6, n7, n8, n10, n20, n50, n100, n200},powerRampingStep ENUMERATED {dB0, dB2, dB4, dB6},ra-ResponseWindow ENUMERATED {sl1, sl2, sl4, sl8, sl10, sl20, sl40, sl80},...,[[prach-ConfigurationPeriodScaling-IAB-r16 ENUMERATED {scf1,scf2,scf4,scf8,scf16,scf32,scf64} OPTIONAL, -- Need Rprach-ConfigurationFrameOffset-IAB-r16 INTEGER (0..63) OPTIONAL, -- Need Rprach-ConfigurationSOffset-IAB-r16 INTEGER (0..39) OPTIONAL, -- Need Rra-ResponseWindow-v1610 ENUMERATED { sl60, sl160} OPTIONAL, -- Need Rprach-ConfigurationIndex-v1610 INTEGER (256..262) OPTIONAL -- Need R]],[[ra-ResponseWindow-v1700 ENUMERATED {sl240, sl320, sl640, sl960, sl1280, sl1920, sl2560} OPTIONAL -- Need R]]}-- TAG-RACH-CONFIGGENERIC-STOP-- ASN1STOP·msg1-FDMThe number of PRACH transmission occasions FDMed in one time instance. (see TS 38.211

[0016] , clause 6.3.3.2).·msg1-FrequencyStartOffset of lowest PRACH transmission occasion in frequency domain with respective to PRB 0. The value is configured so that the corresponding RACH resource is entirely within the bandwidth of the UL BWP. (see TS 38.211

[0016] , clause 6.3.3.2).·powerRampingStepPower ramping steps for PRACH (see TS 38.321 [3],5.1.3). This field is set to the same value for different repetition numbers associated with a specific FeatureCombination.·prach-ConfigurationIndexPRACH configuration index. For prach-ConfigurationIndex configured under beamFailureRecoveryConfig, the prach-ConfigurationIndex can only correspond to the short preamble format, (see TS 38.211

[0016] , clause 6.3.3.2).If the field prach-ConfigurationIndex-v1610 is present, the UE shall ignore the value provided in prach-ConfigurationIndex (without suffix).·preambleReceivedTargetPowerThe target power level at the network receiver side (see TS 38.213

[0013] , clause 7.4, TS 38.321 [3], clauses 5.1.2, 5.1.3). Only multiples of 2 dBm may be chosen (e.g. -202, -200, -198, ...). This field is set to the same value for different repetition numbers associated with a specific FeatureCombination.·preambleTransMaxMax number of RA preamble transmission performed before declaring a failure (see TS 38.321 [3], clauses 5.1.4, 5.1.5).·ra-ResponseWindowMsg2 (RAR) window length in number of slots. The network configures a value lower than or equal to 10 ms when Msg2 is transmitted in licensed spectrum and a value lower than or equal to 40 ms when Msg2 is transmitted with shared spectrum channel access (see TS 38.321 [3], clause 5.1.4). UE ignores the field if included in SCellConfig.If ra-ResponseWindow-v1610 or ra-ResponseWindow-v1700 is signaled, UE shall ignore the ra-ResponseWindow (without suffix). The field ra-ResponseWindow-v1700 is applicable to SCS 480 kHz and SCS 960 kHz.

[0226] For convenience of explanation below, the present disclosure assumes a DL sTRP / UL 2TRP environment in which a UE uses one TRP for performing DL and UL communications and one TRP for performing only UL communications. However, the embodiments described below can also be applied to a DL sTRP / UL mTRP environment using a DL sTRP and three or more UL TRPs. In the description below, a first TRP is a TRP that provides both DL and UL communications with a UE, and a second TRP is a TRP that provides only UL communications with a UE. Here, the first TRP and the second TRP may belong to a single base station (e.g., a gNB) or may belong to different base stations. When the first TRP and the second TRP belong to different base stations, the base stations may have a link for signaling according to the embodiments described below.

[0227]

[0228] FIG. 12 illustrates an example of a procedure for performing random access of a terminal according to one embodiment of the present disclosure. FIG. 12 illustrates an operation method of the terminal.

[0229] Referring to FIG. 12, in step S1201, the terminal performs a random access procedure for accessing a base station including a first TRP and a second TRP, and establishes a connection. For example, the terminal may receive a synchronization signal, receive system information, transmit a random access preamble, receive a random access response, and transmit and / or receive at least one message for connection setup and / or contention resolution. Through this, the terminal may establish a connection to the base station and communicate with the base station. At this time, transmission and / or reception parameters identical or similar to those of the first TRP may be applied to the TRP used for the random access procedure (e.g., establishing a QCL relationship, including the same TAG, etc.). Accordingly, the terminal may obtain control information, parameters, configuration information, etc. applicable to transmission and / or reception for the first TRP.

[0230] In step S1203, the terminal receives a PDCCH order from the first TRP. The PDCCH order is a signaling indicating the initiation of a random access procedure. For example, the PDCCH order is a DCI having a designated DCI format (e.g., format 1_0 or a format defined to indicate random access for another TRP), and a specific parameter (e.g., frequency domain resource allocation) may be set to a designated value. In this case, according to an embodiment of the present disclosure, the PDCCH order may include information indicating or inducing the performance of a random access procedure for the second TRP. For example, the information indicating or inducing the performance of a random access procedure for the second TRP may be expressed explicitly or implicitly.

[0231] In step S1205, the terminal performs a random access procedure for the second TRP. The terminal performs the random access procedure in response to receiving a PDCCH order. That is, the terminal can transmit a random access preamble and receive a response thereto (e.g., a random access response message or message B). Here, the response is received via DL and can be received from the first TRP. At this time, the terminal can recognize whether random access is performed for the second TRP based on the PDCCH order or based on the response.

[0232]

[0233] FIG. 13 illustrates an example of a procedure for performing random access of a base station according to one embodiment of the present disclosure. FIG. 13 illustrates an operating method of a base station.

[0234] Referring to FIG. 13, in step S1301, the base station performs a random access procedure for connection of a terminal and establishes a connection. For example, the base station may transmit a synchronization signal, transmit system information, receive a random access preamble from the terminal, transmit a random access response, and receive and / or transmit at least one message for connection establishment and / or contention resolution. Through this, the terminal may establish a connection and communicate with the base station. At this time, the terminal may obtain control information, parameters, configuration information, etc. applicable to transmission and / or reception for the first TRP.

[0235] In step S1303, the base station transmits a PDCCH order via the first TRP. The PDCCH order is a signaling indicating the initiation of a random access procedure. For example, the PDCCH order is a DCI having a designated DCI format (e.g., format 1_0 or a format defined to indicate random access for another TRP), and a specific parameter (e.g., frequency domain resource allocation) may be set to a designated value. In this case, according to an embodiment of the present disclosure, the PDCCH order may include information indicating or inducing the performance of a random access procedure for a second TRP. For example, the information indicating or inducing the performance of a random access procedure for the second TRP may be expressed explicitly or implicitly.

[0236] In step S1305, the base station performs a random access procedure for the second TRP. That is, the base station performs the random access procedure based on the PDCCH order. That is, the base station can receive a random access preamble through the second TRP and transmit a response thereto (e.g., a random access response message or message B). Here, since the response is transmitted through the DL, it can be transmitted through the first TRP. In this case, according to one embodiment, the base station can transmit information notifying the terminal whether random access is performed for the second TRP through the response.

[0237] The procedure described with reference to FIG. 13 is an embodiment for a case where the first TRP and the second TRP belong to a single base station. If the first TRP belongs to the first base station and the second TRP belongs to the second base station, step S1305 may be performed by the second base station. In this case, the first base station may receive information included in a message to be transmitted via DL from the second base station (e.g., information for a response to a random access preamble) and transmit a message including the received information to the terminal.

[0238]

[0239] The present disclosure below describes various embodiments of random access to a second TRP that supports only UL communications. For convenience of explanation, it is assumed that the UE is connected to the first TRP through a random access procedure. In the various embodiments described below, a PDCCH order-based random access procedure is performed for the UE to initially connect and establish a connection with the second TRP.

[0240]

[0241] FIG. 14 illustrates a first example of a procedure for performing random access to a UL TRP according to one embodiment of the present disclosure. FIG. 14 illustrates signal exchange between a first TRP, a second TRP, and a UE.

[0242] Referring to FIG. 14, in step S1401, the first TRP transmits a PDCCH order to the UE. In other words, the first TRP transmits a command to the UE for performing a random access procedure. The PDCCH order may indicate the performance of contention-based random access (CBRA) or contention-free random access (CFRA). The PDCCH order may include at least one of: an instruction for performing a random access procedure, information about a target of the random access procedure, or preamble allocation information for the random access procedure.

[0243] At step S1403, the UE transmits MSG1 (message 1) to the second TRP. In other words, the UE transmits a random access preamble. To this end, the UE may transmit at least one random access preamble using at least one of the random access occasions (RAOs) within the random access channel identified through system information or configuration information. Through this, the second TRP may determine at least one of the path loss (PL) for the channel with the UE, the transmission timing of the UE, or the preferred transmission beam of the UE.

[0244] In step S1405, the second TRP transmits connection-related information to the first TRP. That is, the second TRP shares connection-related information with the first TRP. For example, the connection-related information may include at least one of information about the PL, information about the UL transmission timing (e.g., timing advance (TA)), or information about the UL transmission beam.

[0245] At step S1407, the first TRP transmits MSG2 (message 2) to the UE. In other words, the first TRP transmits a random access response message to the UE. Here, the random access response message may include at least a portion of the connection-related information received from the second TRP. That is, the first TRP transmits the random access response message via DL on behalf of the second TRP.

[0246]

[0247] FIG. 15 illustrates a second example of a procedure for performing random access to a UL TRP according to one embodiment of the present disclosure. FIG. 15 illustrates signal exchange between a first TRP, a second TRP, and a UE.

[0248] Referring to FIG. 15, in step S1501, the first TRP transmits a PDCCH order to the UE. In other words, the first TRP transmits a command to the UE for performing a random access procedure. The PDCCH order may instruct the UE to perform a CBRA or CFRA. The PDCCH order may include at least one of: an instruction for performing a random access procedure, information about a target of the random access procedure, or preamble allocation information for the random access procedure.

[0249] In step S1503, the UE transmits MSG1 (message 1) to the second TRP. In other words, the UE transmits a random access preamble. To this end, the UE may transmit at least one random access preamble using at least one of the RAOs within the random access channel identified through system information or configuration information. Through this, the second TRP may determine at least one of the PL for the channel with the UE, the UE's transmission timing, or the UE's preferred transmission beam.

[0250] In step S1505, the second TRP transmits connection-related information to the first TRP. That is, the second TRP shares connection-related information with the first TRP. For example, the connection-related information may include at least one of information about the PL, information about the UL transmission timing (e.g., TA), or information about the UL transmission beam.

[0251] In step S1507, the first TRP transmits MSG2 (message 2) to the UE. In other words, the first TRP transmits a random access response message to the UE. Here, the random access response message may include at least a portion of the connection-related information received from the second TRP. In other words, the first TRP transmits the random access response message via DL on behalf of the second TRP.

[0252] At step S1509, the UE transmits MSG3 (message 3) to the second TRP. MSG3 may include a message requesting setup of an RRC connection. The UE may transmit MSG3 via uplink resources allocated by the UL grant included in the random access response. MSG3 may include identification information of the UE.

[0253] At step S1511, the second TRP transmits MSG4 (message 4)-related information to the first TRP. That is, the second TRP shares connection-related information with the first TRP. For example, the MSG4-related information may include contention resolution information.

[0254] At step S1513, the first TRP transmits MSG4 to the UE. In other words, the first TRP transmits a response to MSG3 to the UE. Here, MSG4 may include at least a portion of the MSG4-related information received from the second TRP. That is, the first TRP transmits MSG4 via DL on behalf of the second TRP.

[0255]

[0256] FIG. 16 illustrates a third example of a procedure for performing random access to a UL TRP according to one embodiment of the present disclosure. FIG. 16 illustrates signal exchange between a first TRP, a second TRP, and a UE.

[0257] Referring to FIG. 16, in step S1601, the first TRP transmits a PDCCH order to the UE. In other words, the first TRP transmits a command to the UE for performing a random access procedure. The PDCCH order may instruct the UE to perform a CBRA or CFRA. The PDCCH order may include at least one of: an instruction for performing a random access procedure, information about a target of the random access procedure, or preamble allocation information for the random access procedure.

[0258] At step S1603, the UE transmits MSG1 (message 1) to the second TRP. In other words, the UE transmits a random access preamble. To this end, the UE may transmit at least one random access preamble using at least one of the RAOs within the random access channel identified through system information or configuration information. Through this, the second TRP may determine at least one of the PL for the channel with the UE, the UE's transmission timing, or the UE's preferred transmission beam.

[0259] In step S1605, the second TRP transmits connection-related information to the first TRP. That is, the second TRP shares connection-related information with the first TRP. For example, the connection-related information may include at least one of information about the PL, information about the UL transmission timing (e.g., TA), or information about the UL transmission beam.

[0260] At step S1607, the first TRP transmits MSG2 (message 2) to the UE. In other words, the first TRP transmits a random access response message to the UE. Here, the random access response message may include at least a portion of the connection-related information received from the second TRP. That is, the first TRP transmits the random access response message via DL on behalf of the second TRP.

[0261] At step S1609, the UE transmits MSG3 (message 3) to the first TRP. MSG3 may include a message requesting the establishment of an RRC connection. The UE may transmit MSG3 via uplink resources allocated by the UL grant included in the random access response. MSG3 may include identification information of the UE.

[0262] At step S1611, the first TRP transmits MSG4 to the UE. In other words, the first TRP transmits a response to MSG3 to the UE. Here, MSG4 may include information regarding contention resolution.

[0263]

[0264] According to the aforementioned procedures, a random access procedure for the second TRP can be performed based on the PDCCH order transmitted through the first TRP. The present disclosure below presents specific examples of each operation of the aforementioned procedures.

[0265]

[0266] Example of PDCCH order

[0267] In FIGS. 14 to 16, the first TRP may instruct the UE to perform CBRA or CFRA with the second TRP using a PDCCH order. For example, the PDCCH order transmitted by the first TRP may be included in the DCI 1_0 format defined in 3GPP NR, or may be included in a newly defined DCI format for cross-TRP PDCCH orders.

[0268] If there is allocation information for a preamble used for MSG1 transmission in the DCI transmitted through the PDCCH order, the UE can perform CFRA using the preamble as shown in FIG. 14. If there is no allocation information for a preamble used for MSG1 transmission in the DCI transmitted through the PDCCH order, the UE can select a preamble for CBRA based on information set by higher layer signaling such as SIB, MAC-CE, or RRC, and perform CBRA as shown in FIG. 15 or FIG. 16. For example, if the DCI 1_0 format is used in the PDCCH order, the allocation information for the preamble may include a random access preamble index. In this case, if the corresponding field is a non-zero value, the UE can perform CFRA for the second TRP as shown in FIG. 14. On the other hand, if the field for the random access preamble index is zero, the UE can perform CBRA for the second TRP as in FIG. 15 or FIG. 16.

[0269] According to one embodiment, in FIGS. 14 to 16 , the PDCCH order may include information indicating random access to a second TRP rather than the first TRP transmitting the PDCCH order. This information may be indicated in various ways. For example, random access to the second TRP may be indicated using 1 bit within the DCI used as the PDCCH order, indicated via an RNTI used for CRC scramble, or indicated by reusing a specific field defined for another purpose within the DCI (e.g., filled with all 0s, all 1s, or filled with bit values ​​of a specific type). Alternatively, a request for random access to the second TRP rather than the first TRP may be indicated by combining the above-described indication methods.

[0270] In the case of a DL sTRP / UL mTRP environment where three or more UL TRPs are used, rather than a DL sTRP / UL 2TRP environment, the base station can use multiple bits in the DCI to indicate that it is an RA to a specific TRP. For example, if 2 bits are used, each UL mTRP indication can be mapped to a combination of 00, 01, 10, and 11, in which case, an indication is possible for one of up to four UL-only TRPs. However, if the indication also expresses an indication of random access to a TRP that communicates both DL and UL, an indication is possible for up to three UL-only TRPs. In addition, a specific TRP among the mTRPs can be indicated through multiple RNTIs used for CRC scrambling, or a specific field used for another purpose in the DCI can be reused (e.g., using a specific bit pattern of 0 and 1). Unlike the aforementioned methods, a procedure can be operated to transmit indication information about a TCI state through a PDCCH order and to set and indicate a specific TRP associated with the TCI state.

[0271] As described above, by indicating that the random access is to a TRP other than the first TRP that transmitted the PDCCH order to the terminal, i.e., the second TRP, in the procedures as shown in FIGS. 14 to 16, the UE can recognize that the current random access procedure is for the second TRP. Accordingly, the UE can recognize that the information (e.g., TA, path loss, and Tx beam-related information) that needs to be applied for UL transmission to the second TRP is information received through the first TRP thereafter. If the information indicating that random access to the second TRP is requested is not included, it is impossible for the UE to distinguish whether the target of the random access is the first TRP or the second TRP, which may result in ambiguity.

[0272] Instead of the aforementioned PDCCH order, indication information indicating that random access is to be performed for the second TRP, not the first TRP, can be signaled via MSG2, as illustrated in FIGS. 14 and 15. In this case, in the MSG1 step, the UE transmits a preamble based on the information indicated and configured via the PDCCH order of the first TRP, and the random access to the second TRP, not the first TRP, is indicated via MSG2. Thereafter, in UL transmission to the second TRP, the UE can recognize and apply information (e.g., TA, path loss, and transmission beam-related information) that should be applied for UL transmission to the second TRP based on the indication and configuration information via MSG2.

[0273]

[0274] Examples for MSG1

[0275] In the embodiments described above, the UE can transmit MSG1 using the preamble and RA resources allocated through the PDCCH order. At this time, information on the transmission beam required for MSG1 transmission can be provided through the PDCCH order. For example, transmission beam information can be indicated by indicating a resource index for SSB or CSI-RS using reserved bit(s) or existing fields in the DCI transmitting the PDCCH order. According to one embodiment, when using DCI format 1_0, the base station can indicate beam information that the UE should use for MSG1 transmission through the SS / PSBCH index.

[0276] In a CFRA such as FIG. 14, when transmitting a PDCCH order based on DCI format 1_0, the base station can indicate beam information that the UE should use for MSG1 transmission through the SS / PBCH index indicated in the DCI format 1_0. Alternatively, since the base station allocates RAO(s) based on the SS / PBCH index and PRACH mask index indicated in the DCI format 1_0, information about the transmission beam can be indicated through reserved bit(s) rather than the SS / PBCH index for flexibility in RAO allocation.

[0277] In a CBRA such as FIG. 15 or FIG. 16, when transmitting a PDCCH order based on DCI format 1_0, all random access preamble indices indicated in DCI format 1_0 may be set to 0. In this case, since the field for the SS / PBCH index is defined as a reserved bit, information about the transmission beam to be used for MSG1 transmission to the second TRP may be indicated using the field. The UE may perform CBRA based on the information about the beam.

[0278] In another embodiment, information about the transmission beam may not be transmitted via DCI, but may be set via higher layer signaling, such as MAC-CE or RRC, prior to MSG1 transmission. In this case, TA information and path loss-related information applicable to MSG1 transmission may be indicated or set together.

[0279] Alternatively, the aforementioned methods and configuration information may be set and indicated through a combination of multiple signaling methods such as DCI, MAC-CE, and RRC.

[0280]

[0281] MSG1 can be transmitted in a beam sweeping manner. Beam sweeping can be performed using one RAO or multiple RAOs. Beam sweeping of MSG1 can be performed as shown in Fig. 17.

[0282] FIG. 17 illustrates an example of a procedure for performing random access using beam sweeping according to one embodiment of the present disclosure. FIG. 17 illustrates a procedure in which MSG1, i.e., a random access preamble, is transmitted in a beam sweeping format using at least one RAO.

[0283] Referring to FIG. 17, in step S1701, the first TRP transmits a PDCCH order to the UE. In other words, the first TRP transmits a command to the UE for performing a random access procedure. The PDCCH order may include at least one of an instruction for performing the random access procedure or preamble allocation information for the random access procedure. In addition, according to one embodiment, the PDCCH order may include configuration information for a transmission beam for MSG1. Alternatively, according to another embodiment, the configuration information for the transmission beam may be transmitted via a separate message.

[0284] At step S1703, the UE transmits MSG1 (message 1) to the second TRP. In other words, the UE transmits a random access preamble. At this time, according to one embodiment, the UE repeatedly transmits the random access preamble, i.e., performs beam sweeping. To this end, the UE may perform beam sweeping using at least one of the RAOs within the random access channel identified through system information or configuration information.

[0285] At step S1705, the UE performs the remaining procedures for CFRA or CBRA. For example, the UE may signal the first TRP and / or the second TRP, as well as MSG2, MSG3, MSG4, etc. Through this, the UE can establish a connection with the second TRP and perform communication according to the DL sTRP / UL 2TRP scenario.

[0286] As described with reference to FIG. 17, when the first TRP transmits configuration information about a plurality of transmission beams to the UE, the random access preamble may be transmitted in a beam sweeping manner using the plurality of transmission beams set by the first TRP. According to another embodiment, when the first TRP does not provide the UE with configuration information about the transmission beams, the UE may transmit the preamble in a beam sweeping manner using any plurality of transmission beams. Through this, the second TRP may estimate at least one transmission beam that the UE can use for UL communication. Here, according to one embodiment, information about at least one transmission beam that the UE can use for UL communication may be indicated or transmitted to the UE through MSG2.

[0287]

[0288] According to one embodiment, beam sweeping of MSG1 may be performed within one RAO section. In the embodiments described with reference to FIGS. 14 to 16, MSG1, i.e., a random access preamble, is transmitted within one RAO. If the first TRP configures one transmission beam, the preamble may be transmitted using the transmission beam configured in one RAO. If the first TRP transmits configuration information for multiple transmission beams to the UE, or if the first TRP does not transmit configuration information for a transmission beam to the UE, the UE may transmit the preamble (e.g., MSG1) in at least one RAO using a beam sweeping method.

[0289] A slot structure for transmitting MSG1 in a beam sweeping manner in at least one RAO is as shown in FIG. 18. FIG. 18 illustrates an example of a slot structure in which beam sweeping is performed according to an embodiment of the present disclosure. Referring to FIG. 18, one time slot may be configured to include 14 symbols. For example, when at least one RAO is configured within the slot, the number of transmissions of a random access preamble through beam sweeping may be determined according to the preamble length and the length of the RAO section. Specific examples of the number of transmissions according to the preamble length and the length of the RAO section are as follows [Table 14].

[0290] Case Preamble length Length of RAO section Number of MSG1 transmissions 12 symbol 1 time slot (0 th ~ 13 th symbol)722 symbol6 symbols (7 th ~ 12 th symbol)334 symbol8 symbols (0 th ~7 th symbol)2

[0291] Referring to FIG. 18 and [Table 14], the following beam sweeping operation is possible. In FIG. 18, it is assumed that the RAO resource size in the frequency domain is set. In [Table 14], the length of the preamble refers to the number of symbols required for preamble transmission when considering the resource size of the frequency domain for the RAO resource. The RAO interval refers to a resource that can be set in a specific symbol area within the slot, and refers to a time-domain resource occupied by one RAO. Therefore, in case 1 in [Table 14], the preamble length is 2 symbols, and one time slot is entirely set as an RAO interval. In this case, a total of 7 MSG1 transmissions are possible through 14 symbols. That is, the UE can perform beam sweeping transmission by repeatedly transmitting the preamble 7 times within the slot using 7 different transmission beams. In Case 2, since the preamble length is 2 symbols and the RAO interval is set to 6 symbols, preamble transmission through beam sweeping including a total of 3 repeated transmissions is possible. In Case 3, since the preamble length is 4 symbols and the RAO interval is set to 8 symbols, preamble transmission through beam sweeping including a total of 2 repeated transmissions is possible. The configuration information for the above-described methods can be set and indicated by a combination of one or more signaling methods such as DCI, MAC-CE, and RRC including PDCCH order information.

[0292] As described above, beam sweeping of a random access preamble can be performed through a single RAO. In other words, multiple transmissions can be performed through a single RAO. This means that when configuring an RAO interval, the RAO interval must be set to be longer than the length of the preamble. Conversely, by utilizing multiple RAOs, beam sweeping is possible even if the RAO interval is not configured to be longer than the length of the preamble.

[0293] In another embodiment, beam sweeping of MSG1 may be performed using multiple RAOs. If the first TRP transmits configuration information about multiple transmission beams to the UE, or if the first TRP fails to transmit configuration information about a transmission beam to the UE, the UE may transmit a random access preamble (e.g., MSG1) in a beam sweeping manner using the multiple RAOs. That is, if the first TRP transmits configuration information about multiple transmission beams to the UE, the UE may transmit the preamble in a beam sweeping manner using the multiple transmission beams configured by the first TRP. On the other hand, if the first TRP does not configure configuration information about at least one transmission beam to the UE, the UE may transmit the preamble in a beam sweeping manner using any of multiple transmission beams. Through this, the second TRP may estimate a transmission beam that the UE can use for UL communication, and information about the estimated transmission beam may be signaled to the UE via MSG2.

[0294] For beam sweeping transmissions across multiple RAOs, the first TRP can allocate and configure temporally distinct RAOs to the UE. Information about resources for the RAOs can be signaled via one or a combination of two or more of RRC, MAC-CE, and DCI.

[0295] When configuring temporally consecutive RAOs via DCI format 1_0, temporally distinct RAOs can be configured and / or allocated by utilizing some of the five reserved indices (e.g., indices 11 to 15 in [Table 9]) in the PRACH Mask Index indicated by the 4-bit field. For example, the configuration and allocation of temporally distinct RAOs can be signaled by using a combination of SSB / PBCH indices together with the PRACH Mask Index.

[0296]

[0297] Fig. 19 illustrates examples of RAOs for random access according to one embodiment of the present disclosure. Fig. 19 shows an example in which two RAOs are arranged on the frequency axis and 32 RAOs are arranged on the time axis. Among the RAOs as shown in Fig. 19, the UE must configure or be allocated multiple RAOs that are temporally different for beam sweeping of the preamble. For example, RAOs that are consecutive in the time axis in the same frequency resource region may be configured, such as RAO#0, RAO#2, and RAO#4. Alternatively, RAOs that are consecutive in the time axis and have a certain interval in the same frequency resource region may be configured, such as RAO#0, RAO#4, and RAO#8. Alternatively, RAOs that include different frequency resource regions and are consecutive in the time axis may be configured, such as RAO#0, RAO#3, and RAO#4. Alternatively, consecutive RAOs, such as RAO#0, RAO#5, and RAO#8, may be configured, each containing different frequency resource areas and spaced at regular intervals on the time axis.

[0298] The methods of MSG1 beam sweeping transmission in one RAO and / or MSG1 beam sweeping transmission using multiple RAOs as described above can be operated in a simple modified, expanded, or combined form.

[0299]

[0300] Examples of connection-related information

[0301] In the various embodiments described above, connection-related information is transmitted from the second TRP to the first TRP. According to various embodiments, the connection-related information may include the following information. The second TRP may transmit, to the first TRP, a transmission beam, PL or PL offset, or TA or TA offset acquired and estimated by receiving MSG1 transmitted by the UE, as connection-related information. In this case, the PL offset may indicate a difference in PL between the first TRP and the UE and a difference in PL between the second TRP and the UE, and the TA offset may indicate a difference in TA between the first TRP and the UE and a difference in TA between the second TRP and the UE. In addition, the information about the transmission beam may be transmitted to the first TRP in the form of a TCI state. Alternatively, the information about the transmission beam may be transmitted in the form of at least one of an RAO index, a symbol index, or preamble information in which MSG1 is received, or may be transmitted in a combination or modified form of the listed parameters.

[0302]

[0303] Examples for MSG2

[0304] The first TRP may transmit MSG2 to the UE, which includes transmission beam information, PL information, TA information, etc., required for UL transmission to the second TRP. At least one of the items included in MSG2 may be configured through a combination of at least one of DCI, PDSCH, MAC-CE, or RRC signaling.

[0305] Transmit beam information can be indicated using the UL TCI state. In this case, PL information or TA information related to the second TRP can be signaled in an associated manner with the UL TCI state. One UL TCI state can be indicated in a manner associated with the PL offset and TA offset for the second TRP. In this case, based on the association with the TCI state, information about PL and TA can be signaled to the UE only with the indication of the UL TCI state.

[0306]

[0307] Examples for MSG3 and MSG4

[0308] In the embodiment described with reference to FIG. 15, in signaling for contention resolution, i.e., signaling of MSG3 and MSG4, MSG3 may be transmitted to the second TRP. Since the second TRP cannot perform DL transmission, it may transmit information necessary for contention resolution to the first TRP. For example, the second TRP may transmit the UE's RNTI information to the first TRP. The RNTI may include the C-RNTI. Thereafter, the first TRP may transmit MSG4 to the UE for contention resolution.

[0309] In the embodiment described with reference to FIG. 16, in signaling for contention resolution, i.e., signaling for MSG3 and MSG4, the UE may transmit MSG3 to the first TRP. Thereafter, the first TRP may transmit MSG4 to the UE for contention resolution.

[0310]

[0311] According to the various embodiments described above, a random access procedure for a second TRP may be performed according to a PDCCH order transmitted through a first TRP. In the embodiment described above, the first TRP supports DL and UL communications, and the second TRP supports only UL communications. The embodiments described above may also be applied to other types of TRPs. For example, even when the first TRP is a TRP that performs a half-duplex (HD) operation and the second TRP is a TRP that performs a full-duplex (FD) operation, a PDCCH order indicating the performance of a random access for the second TRP may be transmitted through the first TRP according to the embodiments described above. Here, the FD operation may be understood as transmitting and receiving through UL and DL subbands configured for SBFD in an SBFD (subband full duplex) symbol. At this time, if RAOs for random access to a first TRP supporting HD operation and RAOs for random access to a second TRP supporting FD operation are separately allocated, a request for random access to the second TRP can be indicated by indicating the use of an additional RAO ​​allocated to the SBFD symbol.

[0312] Conversely, a PDCCH order indicating the performance of random access to the first TRP through the second TRP may be transmitted according to the aforementioned embodiments. In this case, if RAOs for random access to the first TRP supporting HD operation and RAOs for random access to the second TRP supporting FD operation are separately allocated, a request for random access to the first TRP may be indicated by indicating the use of a legacy RAO allocated to a non-SBFD symbol.

[0313]

[0314] The operations of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0315] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0316] While some aspects of the present disclosure have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0317] A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

[0318] Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

Claims

1. In a method of operating a terminal in a wireless communication system, A step of performing a first random access procedure to access a base station including a first transmission-reception point (TRP) and a second TRP; A step of receiving a PDCCH (physical downlink control channel) order from the first TRP; and A method comprising the step of performing a second random access procedure for a second TRP based on the above PDCCH order.

2. In claim 1, A method wherein the PDCCH order includes information that directs or induces the performance of a random access procedure for the second TRP.

3. In claim 2, A method wherein the information comprises at least one of an explicit indicator, a radio network temporary identifier (RNTI) for cyclic redundancy check (CRC) scrambling, a specific bit pattern of a designated field, or a transmission configuration information (TCI) state associated with the second TRP.

4. In claim 1, The step of performing the above second random access procedure is: A step of performing a contention free random access (CFRA) procedure when the above PDCCH order includes allocation information for a preamble; A method comprising a step of performing a contention based random access (CBRA) procedure when the above PDCCH order does not include allocation information for a preamble.

5. In claim 1, The step of performing the above second random access procedure is: A step of transmitting a random access preamble to the second TRP; A method comprising the step of receiving a random access response message from the first TRP.

6. In claim 5, A method wherein the random access response message includes information instructing the performance of a random access procedure for the second TRP.

7. In claim 5, The step of performing the above second random access procedure is: A step of performing UL transmission to the second TRP based on at least one parameter for UL transmission included in the random access response message, A method wherein at least one of the above parameters is related to at least one of timing advance (TA), path loss, or transmission beam.

8. In claim 5, The step of transmitting a random access preamble to the second TRP is: A method comprising the step of transmitting the random access preamble based on information about a transmission beam included in the PDCCH order.

9. In claim 5, The step of transmitting a random access preamble to the second TRP is: A method comprising the step of transmitting the random access preamble based on information about a transmission beam included in a received message prior to receiving the PDCCH order.

10. In claim 1, The step of performing the above second random access procedure is: A method comprising the step of repeatedly transmitting a random access preamble through beam sweeping using multiple transmission beams.

11. In claim 10, A method in which the plurality of transmission beams are used when information about the plurality of transmission beams is provided from the first TRP, or when information about a transmission beam for transmitting a RACH preamble to the second TRP is not provided by the first TRP.

12. In claim 10, The step of performing the above second random access procedure is: A step of receiving a random access response message including information about at least one beam among the plurality of transmission beams; A method comprising the step of performing UL transmission to the second TRP using at least one beam.

13. In claim 10, A method in which the number of repeated transmissions of the RACH preamble through the beam sweeping is determined based on the length of a random access ocassion (RAO) period within a slot and the length of the random access preamble.

14. In claim 10, A method further comprising the step of receiving allocation information for a plurality of RAOs for the beam sweeping.

15. In a method of operating a base station in a wireless communication system, A step of performing a first random access procedure for terminal connection; A step of transmitting a PDCCH (physical downlink control channel) order to the terminal through a first TRP (transmission-reception point); A method comprising the step of performing a second random access procedure for a second TRP based on the above PDCCH order.

16. In claim 15, A method wherein the PDCCH order includes information that directs or induces the performance of a random access procedure for the second TRP.

17. In claim 16, A method wherein the information comprises at least one of an explicit indicator, a radio network temporary identifier (RNTI) for cyclic redundancy check (CRC) scrambling, a specific bit pattern of a designated field, or a transmission configuration information (TCI) state associated with the second TRP.

18. In claim 15, The step of performing the above second random access procedure is: A step of receiving a random access preamble from the terminal through the second TRP; and A method comprising the step of transmitting a random access response message through the first TRP.

19. In a wireless communication system, at a terminal, At least one transmitter / receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed by said processor, control said terminal to perform operations; The above actions are, A step of performing a first random access procedure to access a base station including a first transmission-reception point (TRP) and a second TRP; A step of receiving a PDCCH (physical downlink control channel) order from the first TRP; A terminal comprising a step of performing a second random access procedure for a second TRP based on the above PDCCH order.

20. In a base station in a wireless communication system, At least one transmitter / receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed by said processor, control said base station to perform operations; The above actions are, A step of performing a first random access procedure for terminal connection; A step of transmitting a PDCCH (physical downlink control channel) order to the terminal through a first TRP (transmission-reception point); and A base station, comprising a step of performing a second random access procedure for a second TRP based on the above PDCCH order.

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