Method and apparatus for transmitting and receiving uplink data in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present disclosure relates to the operation of a terminal and a base station in a wireless communication system and, particularly, to a method for transmitting and receiving an uplink reference signal in a wireless communication system, and an apparatus capable of performing same. The present disclosure provides an apparatus and method capable of effectively providing a service in a mobile communication system.

Description

Method and device for transmitting and receiving uplink data in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a method for transmitting and receiving uplink data in a wireless communication system and a device capable of performing the method.

[0002] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in the sub-6GHz frequency band such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band called millimeter wave (mmWave) such as 28GHz and 39GHz ('Above 6GHz'). In addition, for 6G mobile communication technology, which is called the system after 5G communication (Beyond 5G), implementation in the terahertz band (for example, the 3 terahertz (3THz) band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and satisfy performance requirements for enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase the transmission distance of radio waves, support for various numerologies (such as operation of multiple subcarrier intervals) and dynamic operation of slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (Bidth Part), new channel coding methods such as LDPC (Low Density Parity Check) codes for large-capacity data transmission and Polar Code for reliable transmission of control information, and L2 pre-processing (L2). Standardization has been made for network slicing, which provides dedicated networks specialized for specific services, and pre-processing.

[0004] Currently, discussions are underway to improve and enhance the initial 5G mobile communication technology in consideration of the services that 5G mobile communication technology was intended to support, and physical layer standardization is in progress for technologies such as V2X (Vehicle-to-Everything) to help autonomous vehicles make driving decisions and increase user convenience based on their own location and status information transmitted by vehicles, NR-U (New Radio Unlicensed) for the purpose of system operation that complies with various regulatory requirements in unlicensed bands, NR terminal low power consumption technology (UE Power Saving), Non-Terrestrial Network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with terrestrial networks is impossible, and Positioning.

[0005] In addition, standardization of wireless interface architecture / protocols is in progress for technologies such as intelligent factories (Industrial Internet of Things, IIoT) to support new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) that provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement technology including Conditional Handover and Dual Active Protocol Stack (DAPS) handover, and 2-step random access (2-step RACH for NR) that simplifies random access procedures. Standardization is also in progress for system architecture / services such as 5G baseline architecture (e.g., Service-based Architecture, Service-based Interface) for grafting Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) that provides services based on the location of the terminal.

[0006] Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices. To this end, new research will be conducted on improving 5G performance and reducing complexity, supporting AI services, supporting metaverse services, and drone communications by utilizing eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0007] In addition, the development of these 5G mobile communication systems includes new waveforms to ensure coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), Array Antenna, and Large Scale Antenna, metamaterial-based lenses and antennas to improve the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), Reconfigurable Intelligent Surface (RIS) technology, as well as full duplex technology to improve the frequency efficiency and system network of 6G mobile communication technology, satellite, AI (Artificial Intelligence) from the design stage and AI-based communication technology that realizes system optimization by internalizing end-to-end AI support functions, and ultra-high-performance communication and computing resources to provide services with complexity that exceeds the limits of terminal computing capabilities. It can serve as a basis for the development of next-generation distributed computing technologies that can be realized by utilizing them.

[0008] The disclosed embodiment seeks to provide a device and method capable of effectively providing a service in a mobile communication system.

[0009] The present invention for solving the above problems is characterized by a method performed by a terminal in a wireless communication system, comprising the steps of: transmitting an uplink reference signal to a base station; receiving uplink precoder information determined based on the uplink reference signal from the base station; receiving scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information from the base station; and performing uplink transmission based on the uplink precoder indicated based on the indicator.

[0010] In addition, the present invention for solving the above problem is characterized by a method performed by a base station in a wireless communication system, comprising the steps of: receiving an uplink reference signal from a terminal; estimating an uplink channel based on the uplink reference signal; transmitting uplink precoder information determined based on the estimated uplink channel to the terminal; transmitting scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information to the terminal; and receiving data from the terminal based on the uplink precoder indicated based on the indicator.

[0011] In addition, the present invention for solving the above problems is characterized in that, in a wireless communication system, a terminal includes at least one transceiver, at least one processor communicatively connected to the at least one transceiver, and a memory communicatively connected to the at least one processor and capable of executing the at least one processor individually or in any combination, such that the terminal transmits an uplink reference signal to a base station, receives uplink precoder information determined based on the uplink reference signal from the base station, receives scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information from the base station, and performs uplink transmission based on the uplink precoder indicated based on the indicator.

[0012] In addition, the present invention for solving the above problems is characterized in that, in a base station in a wireless communication system, the base station includes at least one transceiver, at least one processor communicatively connected to the at least one transceiver, and a memory for storing instructions communicatively connected to the at least one processor and executable individually or in any combination of the at least one processor, such that the base station receives an uplink reference signal from a terminal, estimates an uplink channel based on the uplink reference signal, transmits uplink precoder information determined based on the estimated uplink channel to the terminal, transmits scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information to the terminal, and receives data from the terminal based on the uplink precoder indicated based on the indicator.

[0013] The disclosed embodiment provides a device and method capable of effectively providing a service in a mobile communication system.

[0014] FIG. 1 is a diagram illustrating a basic structure of a time-frequency domain in a wireless communication system according to one embodiment of the present disclosure.

[0015] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to one embodiment of the present disclosure.

[0016] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to one embodiment of the present disclosure.

[0017] FIG. 4 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation in a wireless communication system according to one embodiment of the present disclosure.

[0018] FIG. 5 is a diagram of a beam application time that can be considered when using an integrated TCI method in a wireless communication system according to an embodiment of the present disclosure.

[0019] FIG. 6 is a diagram illustrating another MAC-CE structure for activating and indicating a joint TCI state or a separate DL or UL TCI state in a wireless communication system according to an embodiment of the present disclosure.

[0020] FIG. 7 is a diagram illustrating an example of setting a control region of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0021] FIG. 8 is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0022] FIG. 9 is a diagram illustrating an SRS antenna switching operation according to an embodiment of the present disclosure.

[0023] Figure 10 illustrates a process for beam setting and activation of PDSCH.

[0024] FIG. 11 is a diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.

[0025] FIG. 12 is a diagram illustrating an example of configuring downlink control information (DCI) for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.

[0026] Figure 13 is a diagram showing an Enhanced PDSCH TCI state activation / deactivation MAC-CE structure.

[0027] FIG. 14 is a diagram illustrating an uplink transmission and reception method between a terminal and a base station according to one embodiment of the present disclosure.

[0028] FIG. 15 is a diagram illustrating a non-codebook based uplink transmission process according to one embodiment of the present disclosure.

[0029] FIG. 16 is a diagram showing the operation of a terminal according to an embodiment of the present disclosure.

[0030] FIG. 17 is a diagram illustrating the operation of a base station according to an embodiment of the present disclosure.

[0031] FIG. 18 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0032] FIG. 19 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0033] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0034] In describing the embodiments, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to ensure that the gist of the present disclosure is conveyed more clearly without obscuring it by omitting unnecessary explanations.

[0035] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0036] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, the detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and these may vary depending on the intention or custom of the user or operator. Therefore, their definitions should be made based on the contents throughout the specification.

[0037] Hereinafter, the base station is an entity that performs resource allocation of the terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, the downlink (DL) refers to a wireless transmission path of a signal transmitted from the base station to the terminal, and the uplink (UL) refers to a wireless transmission path of a signal transmitted from the terminal to the base station. In addition, although the embodiments of the present disclosure are described below using a 5G system as an example, the embodiments of the present disclosure may also be applied to other communication systems having a similar technical background or channel type. For example, this may include LTE or LTE-A mobile communication and mobile communication technologies developed after 5G. Furthermore, the present disclosure may be applied to other communication systems with some modifications, as determined by a person skilled in the art, without significantly departing from the scope of the present disclosure. The contents of the present disclosure are applicable to FDD and TDD systems.

[0038] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0039] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0040] Here, the term '~ part' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium or may be configured to play one or more processors. Therefore, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ parts' may be combined into a smaller number of components and '~ parts' or further separated into additional components and '~ parts'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~parts' may include one or more processors.

[0041] Wireless communication systems are evolving from providing voice-oriented services in the early days to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards such as 3GPP's HSPA (High Speed ​​Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's HRPD (High Rate Packet Data), UMB (Ultra Mobile Broadband), and IEEE's 802.16e.

[0042] As a representative example of the above broadband wireless communication system, the LTE system adopts the OFDM (Orthogonal Frequency Division Multiplexing) method in the downlink (DL) and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method in the uplink (UL). The uplink refers to a wireless link in which a terminal (User Equipment (UE) or Mobile Station (MS)) transmits data or control signals to a base station (eNode B or base station (BS)), and the downlink refers to a wireless link in which a base station transmits data or control signals to a terminal. The above multiple access method can distinguish the data or control information of each user by allocating and operating the time-frequency resources for transmitting data or control information to each user so that they do not overlap, that is, so as to achieve orthogonality.

[0043] As a future communications system beyond LTE, 5G communication systems must be able to freely reflect the diverse needs of users and service providers. Therefore, they must support services that simultaneously satisfy these diverse requirements. Services being considered for 5G communication systems include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC).

[0044] eMBB aims to provide data transmission rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to support a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink from the perspective of a single base station. Furthermore, 5G communication systems must simultaneously provide the peak data rate and an increased user-perceived data rate for terminals. To meet these requirements, improvements in various transmission and reception technologies, including improved multi-input, multi-output (MIMO) transmission technology, are required. Furthermore, while LTE transmits signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the data transmission rates required by 5G communication systems by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher 6 GHz band.

[0045] At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide the IoT, mMTC requires supporting large-scale terminal connections within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. The IoT requires the ability to support a large number of terminals (e.g., 1,000,000 terminals / km2) within a cell, as it provides communication capabilities through the attachment of various sensors and devices. Furthermore, due to the nature of the service, terminals supporting mMTC are likely to be located in shadow areas, such as basements, beyond cell coverage. This may require broader coverage compared to other services provided by 5G communication systems. Terminals supporting mMTC must be inexpensive, and since frequent battery replacement is unlikely, they may require extremely long battery lifespans, such as 10 to 15 years.

[0046] Finally, URLLC refers to a cellular-based wireless communication service used for a specific purpose (mission-critical). For example, services such as remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, and emergency alerts can be considered. Therefore, the communication provided by URLLC must provide very low latency and very high reliability. For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds and, at the same time, must have a 10 -5The following packet error rate (PER) requirements apply. Therefore, for services supporting URLLC, 5G systems must provide a smaller Transmit Time Interval (TTI) than other services. Simultaneously, design considerations may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0047] The three 5G services—eMBB, URLLC, and mMTC—can be multiplexed and transmitted within a single system. To meet the differing requirements of each service, different transmission and reception techniques and parameters can be used. Of course, 5G is not limited to the three services described above.

[0048] Hereinafter, a / b can be understood as at least one of a or b.

[0049] [NR time-frequency resources]

[0050] Below, the frame structure of the 5G system is described in more detail with reference to drawings.

[0051] Figure 1 is a diagram illustrating the basic structure of the time-frequency domain, which is a radio resource domain in which data or control channels are transmitted in a 5G system.

[0052] The horizontal axis of Figure 1 represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time and frequency domains is a resource element (RE, 101), which can be defined as 1 OFDM symbol (102) on the time axis and 1 subcarrier (103) on the frequency axis. In the frequency domain (For example, 12) consecutive REs can constitute one resource block (RB, 104). One subframe (110) on the time axis can include multiple OFDM symbols (102). For example, the length of one subframe can be 1 ms.

[0053] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to one embodiment of the present disclosure.

[0054] Figure 2 illustrates an example of a structure of a frame (Frame, 200), a subframe (Subframe, 201), and a slot (Slot, 202, 203). One frame (200) can be defined as 10ms. One subframe (201) can be defined as 1ms, and therefore one frame (200) can be composed of a total of 10 subframes (201). One slot (202, 203) can be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( =14). 1 subframe (201) may be composed of one or more slots (202, 203), and the number of slots (202, 203) per 1 subframe (201) may vary depending on the setting value μ (204, 205) for the subcarrier spacing. In an example of FIG. 2, cases where the subcarrier spacing setting value μ = 0 (204) and μ = 1 (205) are illustrated. When μ = 0 (204), 1 subframe (201) may be composed of one slot (202), and when μ = 1 (205), 1 subframe (201) may be composed of two slots (203). That is, the number of slots per 1 subframe ( ) may vary, and accordingly the number of slots per frame ( ) may vary. Depending on the subcarrier spacing setting μ and can be defined as [Table 1] below.

[0055]

[0056] μ 0141011142022144043148084141601651432032

[0057] [Bandwidth Part (BWP)]

[0058] Next, the bandwidth part (BWP) setting in the 5G communication system will be explained in detail with reference to the drawing.

[0059] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to one embodiment of the present disclosure.

[0060] FIG. 3 shows an example in which the UE bandwidth (300) is set to two bandwidth portions, namely, bandwidth portion #1 (BWP#1) (301) and bandwidth portion #2 (BWP#2) (302). The base station can set one or more bandwidth portions to the UE, and can set information such as [Table 2] below for each bandwidth portion.

[0061] BWP ::= SEQUENCE {bwp-Id BWP-Id,(bandwidth part identifier)locationAndBandwidth INTEGER (1..65536),(bandwidth part location)subcarrierSpacing ENUMERATED {n0, n1, n2, n3, n4, n5},(subcarrier spacing)cyclicPrefix ENUMERATED { extended}(cyclic prefix)}

[0062] Of course, the above example is not limited, and in addition to the above configuration information, various parameters related to the bandwidth portion can be configured for the terminal. The above information can be transmitted from the base station to the terminal via upper layer signaling, for example, RRC (Radio Resource Control) signaling. At least one bandwidth portion among the configured one or more bandwidth portions can be activated. Whether or not the configured bandwidth portion is activated can be semi-statically transmitted from the base station to the terminal via RRC signaling or dynamically transmitted via DCI.

[0063] According to some embodiments, a terminal before RRC connection can be configured with an initial bandwidth portion (Initial BWP) for initial access from a base station through a Master Information Block (MIB). More specifically, the terminal can receive configuration information about a control resource set (CORESET) and a search space in which a PDCCH for receiving system information required for initial access (which may correspond to Remaining System Information (RMSI) or System Information Block 1 (SIB1)) and search space can be transmitted through the MIB during the initial access phase. The control space and search space configured by the MIB can each be regarded as identifier (ID) 0. The base station can notify the terminal of configuration information such as frequency allocation information, time allocation information, and numerology for control space #0 through the MIB. Additionally, the base station can notify the terminal of the monitoring cycle and monitoring occasion settings for control area #0, i.e., search space #0, via the MIB. The terminal can consider the frequency range set as control area #0 obtained from the MIB as the initial bandwidth portion for initial access. At this time, the identifier (ID) of the initial bandwidth portion can be considered as 0.

[0064] The settings for the bandwidth supported by the above 5G can be used for various purposes.

[0065] In some embodiments, when the bandwidth supported by a terminal is smaller than the system bandwidth, this can be supported through bandwidth portion configuration. For example, the base station can configure the bandwidth portion frequency location (configuration information 2) for the terminal, thereby allowing the terminal to transmit and receive data at a specific frequency location within the system bandwidth.

[0066] Additionally, in some embodiments, a base station may configure multiple bandwidth segments for a terminal to support different numerologies. For example, to support data transmission and reception using both a 15 kHz subcarrier spacing and a 30 kHz subcarrier spacing for a given terminal, two bandwidth segments may be configured with subcarrier spacings of 15 kHz and 30 kHz, respectively. The different bandwidth segments may be frequency division multiplexed (FDM), and when data is to be transmitted and received using a specific subcarrier spacing, the bandwidth segment configured for the corresponding subcarrier spacing may be activated.

[0067] Furthermore, in some embodiments, the base station may configure bandwidth portions with different bandwidth sizes for the terminal for the purpose of reducing power consumption of the terminal. For example, if the terminal supports a very large bandwidth, such as 100 MHz, and constantly transmits and receives data using that bandwidth, very large power consumption may occur. In particular, monitoring unnecessary downlink control channels using a large bandwidth of 100 MHz in a traffic-free environment may be very inefficient in terms of power consumption. To reduce power consumption of the terminal, the base station may configure a bandwidth portion with a relatively small bandwidth, such as 20 MHz, for the terminal. In a traffic-free environment, the terminal may perform monitoring operations in the 20 MHz bandwidth portion, and when data is generated, it may transmit and receive data using the 100 MHz bandwidth portion according to the instructions of the base station.

[0068] In the method for setting the bandwidth portion, terminals prior to RRC connection (Connected) can receive configuration information for the initial bandwidth portion (Initial BWP) through the MIB during the initial access phase. More specifically, the terminal can receive a control region (i.e., CORESET) for a downlink control channel on which a DCI scheduling a System Information Block (SIB) can be transmitted from the MIB of the Physical Broadcast Channel (PBCH). The bandwidth of the control region set by the MIB can be regarded as the initial bandwidth portion, and the terminal can receive the Physical Downlink Shared Channel (PDSCH) on which the SIB is transmitted through the set initial bandwidth portion. In addition to receiving the SIB, the initial bandwidth portion can also be utilized for other system information (Other System Information (OSI), paging, and random access).

[0069] [Bandwidth Part (BWP) Change]

[0070] When one or more bandwidth part values ​​are set for a terminal, the base station can instruct the terminal to change (or switch, transition) the bandwidth part value using the bandwidth part indicator field in the DCI. For example, in FIG. 3, when the currently activated bandwidth part of the terminal is bandwidth part #1 (301), the base station can instruct the terminal to bandwidth part #2 (302) using the bandwidth part indicator in the DCI, and the terminal can perform a bandwidth part change to bandwidth part #2 (302) indicated by the bandwidth part indicator in the received DCI.

[0071] As described above, since DCI-based bandwidth part change can be indicated by DCI scheduling PDSCH or PUSCH, when a terminal receives a bandwidth part change request, it must be able to receive or transmit PDSCH or PUSCH scheduled by the corresponding DCI without difficulty in the changed bandwidth part. To this end, the standard stipulates the delay time (T) required when changing the bandwidth part. BWP ) and can be defined as in [Table 3] below, for example.

[0072] μNR Slot length (ms)BWP switch delay T BWP (slots)Type 1 Note 1 Type 2 Note 1 011310.52520.253930.125618Note 1: Depends on UE capability.Note 2: If the BWP switch involves changing of SCS, the BWP switch delay is determined by the larger one between the SCS before BWP switch and the SCS after BWP switch.

[0073] The bandwidth-partial change delay time requirement supports Type 1 or Type 2 depending on the terminal's capability. The terminal can report the supported bandwidth-partial delay time type to the base station.

[0074] According to the requirement for bandwidth part change delay time mentioned above, when the terminal receives DCI including bandwidth part change indicator in slot n, the terminal changes to the new bandwidth part indicated by the bandwidth part change indicator in slot n+T. BWPIt can be completed at a later time, and transmission and reception for the data channel scheduled by the DCI can be performed in the new bandwidth portion that has been changed. If the base station wants to schedule a data channel in the new bandwidth portion, the terminal's bandwidth portion change delay time (T BWP ), time domain resource allocation for the data channel can be determined. That is, when the base station schedules a data channel with a new bandwidth portion, the data channel can be scheduled after the bandwidth portion change delay time in the method of determining time domain resource allocation for the data channel. Accordingly, the terminal can determine whether the DCI instructing a bandwidth portion change is after the bandwidth portion change delay time (T BWP ) may not be expected to indicate a slot offset (K0 or K2) value smaller than that.

[0075] If the terminal receives DCI (e.g., DCI format 1_1 or 0_1) indicating a bandwidth change, the terminal may not perform any transmission or reception during the time period corresponding to the third symbol of the slot in which the terminal receives the PDCCH including the DCI, to the start of the slot indicated by the slot offset (K0 or K2) value indicated by the time domain resource allocation indicator field in the DCI. For example, if the terminal receives DCI indicating a bandwidth change in slot n and the slot offset value indicated by the DCI is K, the terminal may not perform any transmission or reception from the third symbol of slot n to the symbol before slot n+K (i.e., the last symbol of slot n+K-1).

[0076] [CA / DC related]

[0077] FIG. 4 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation according to an embodiment of the present disclosure.

[0078] Referring to FIG. 4, the wireless protocol of the next-generation mobile communication system is composed of NR SDAP (Service Data Adaptation Protocol 425, 470), NR PDCP (Packet Data Convergence Protocol 430, 465), NR RLC (Radio Link Control 435, 460), and NR MAC (Medium Access Control 440, 455) in the terminal and NR base station, respectively.

[0079] The main functions of NR SDAP (425, 470) may include some of the following functions:

[0080] - Transfer of user plane data

[0081] - Mapping function between QoS flow and data bearer for both DL and UL

[0082] - Marking function of QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0083] - Ability to map reflective QoS flow to data bearer for the uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0084] For the above SDAP layer device, the terminal can be configured by an RRC message for each PDCP layer device, each bearer, or each logical channel, whether to use the header of the SDAP layer device or whether to use the function of the SDAP layer device, and when the SDAP header is configured, the terminal can instruct the NAS QoS reflection configuration 1-bit indicator (NAS reflective QoS) and the AS QoS reflection configuration 1-bit indicator (AS reflective QoS) of the SDAP header to update or reset the mapping information for the QoS flow and data bearer of the uplink and downlink. The SDAP header can include QoS flow ID information indicating QoS. The QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

[0085] The main functions of NR PDCP (430, 465) may include some of the following functions:

[0086] - Header compression and decompression (ROHC only)

[0087] - User data transfer function

[0088] - In-sequence delivery of upper layer PDUs

[0089] - Out-of-sequence delivery of upper layer PDUs

[0090] - PDCP PDU reordering for reception

[0091] - Duplicate detection of lower layer SDUs

[0092] - Retransmission function (Retransmission of PDCP SDUs)

[0093] - Encryption and decryption functions (Ciphering and deciphering)

[0094] - Timer-based SDU discard in uplink.

[0095] The reordering function of the NR PDCP device above refers to a function of reordering PDCP PDUs received from a lower layer in order based on the PDCP SN (sequence number), and may include a function of transmitting data to an upper layer in the reordered order. Alternatively, the reordering function of the NR PDCP device may include a function of transmitting data directly without considering the order, a function of recording lost PDCP PDUs by reordering the order, a function of reporting a status of lost PDCP PDUs to the transmitting side, and a function of requesting retransmission of lost PDCP PDUs.

[0096] The main functions of NR RLC (435, 460) may include some of the following functions:

[0097] - Data transfer function (Transfer of upper layer PDUs)

[0098] - In-sequence delivery of upper layer PDUs

[0099] - Out-of-sequence delivery of upper layer PDUs

[0100] - ARQ function (Error Correction through ARQ)

[0101] - Concatenation, segmentation and reassembly of RLC SDUs

[0102] - Re-segmentation of RLC data PDUs

[0103] - Reordering of RLC data PDUs

[0104] - Duplicate detection function

[0105] - Protocol error detection

[0106] - RLC SDU discard function

[0107] - RLC re-establishment function

[0108] In the above, the in-sequence delivery function of the NR RLC device refers to the function of sequentially delivering RLC SDUs received from a lower layer to an upper layer. The in-sequence delivery function of the NR RLC device may include a function of reassembling and delivering a single RLC SDU when it is received divided into multiple RLC SDUs, a function of rearranging received RLC PDUs based on the RLC SN (sequence number) or PDCP SN (sequence number), a function of recording lost RLC PDUs by rearranging the order, a function of reporting the status of lost RLC PDUs to the transmitting side, and a function of requesting retransmission of lost RLC PDUs. The in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer only the RLC SDUs up to the lost RLC SDU when there is a lost RLC SDU, or may include a function to sequentially deliver to the upper layer all RLC SDUs received before the timer starts if a predetermined timer has expired even if there is a lost RLC SDU. Alternatively, the in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer all RLC SDUs received up to the present if a predetermined timer has expired even if there is a lost RLC SDU.In addition, the RLC PDUs may be processed in the order in which they are received (in the order of arrival, regardless of the order of the sequence number) and delivered to the PDCP device out of order (out-of-sequence delivery). In the case of segments, the segments stored in the buffer or to be received later may be received, reconstructed into a complete RLC PDU, processed, and delivered to the PDCP device. The NR RLC layer may not include a concatenation function, and the function may be performed in the NR MAC layer or replaced with a multiplexing function of the NR MAC layer.

[0109] The out-of-sequence delivery function of the NR RLC device above refers to the function of directly delivering RLC SDUs received from a lower layer to an upper layer regardless of the order, and may include a function of reassembling and delivering RLC SDUs when one RLC SDU is received divided into multiple RLC SDUs, and may include a function of storing and arranging the RLC SN or PDCP SN of received RLC PDUs to record lost RLC PDUs.

[0110] NR MAC (440, 455) can be connected to multiple NR RLC layer devices configured in one terminal, and the main functions of NR MAC can include some of the following functions.

[0111] - Mapping function (Mapping between logical channels and transport channels)

[0112] - Multiplexing / demultiplexing of MAC SDUs

[0113] - Scheduling information reporting function

[0114] - HARQ function (Error correction through HARQ)

[0115] - Priority handling between logical channels of one UE

[0116] - Priority handling between UEs by means of dynamic scheduling

[0117] - MBMS service identification function

[0118] - Transport format selection function

[0119] - Padding function

[0120] The NR PHY layer (445, 450) can perform operations of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it through a wireless channel, or demodulating and channel decoding OFDM symbols received through a wireless channel and transmitting them to a higher layer.

[0121] The above wireless protocol structure can have various detailed structures depending on the carrier (or cell) operation method. For example, when a base station transmits data to a terminal based on a single carrier (or cell), the base station and the terminal use a protocol structure that has a single structure for each layer, such as S00. On the other hand, when a base station transmits data to a terminal based on CA (carrier aggregation) using multiple carriers in a single TRP, the base station and the terminal use a protocol structure that has a single structure up to RLC, but multiplexes the PHY layer through the MAC layer, such as 410. As another example, when a base station transmits data to a terminal based on DC (dual connectivity) using multiple carriers in multiple TRPs, the base station and the terminal use a protocol structure that has a single structure up to RLC, but multiplexes the PHY layer through the MAC layer, such as 420.

[0122] [Unified TCI state]

[0123] Hereinafter, a single TCI state indication and activation method based on the unified TCI scheme is described. The unified TCI scheme can refer to a method of integrating and managing the transmission and reception beam management methods, which were distinguished into the TCI state method used for downlink reception of the terminal in the existing Rel-15 and 16 and the spatial relation info method used for uplink transmission, into a TCI state. Therefore, when the terminal is instructed by the base station based on the unified TCI scheme, it can perform beam management using the TCI state even for uplink transmission. If the terminal has set a TCI-State, which is an upper layer signaling with the tci-stateId-r17, which is an upper layer signaling, from the base station, the terminal can perform operations based on the unified TCI scheme using the corresponding TCI-State. The TCI-State can exist in two forms: a joint TCI state or a separate TCI state.

[0124] The first type is a joint TCI state, and the terminal can be instructed by the base station to use both the TCI state to apply to uplink transmission and downlink reception through a single TCI-State. If the terminal is instructed to use a TCI-State based on a joint TCI state, the terminal can use the RS corresponding to qcl-Type1 in the TCI-State based on the joint TCI state to instruct the parameters to use for downlink channel estimation, and the RS corresponding to qcl-Type2 to instruct the parameters to use as a downlink reception beam or reception filter. If the terminal is instructed to use a TCI-State based on a joint TCI state, the terminal can use the RS corresponding to qcl-Type2 in the TCI-State based on the joint DL / UL TCI state to instruct the parameters to use as an uplink transmission beam or transmission filter. In this case, if the terminal is instructed to use a joint TCI state, the terminal can apply the same beam to both uplink transmission and downlink reception.

[0125] The second form is a separate TCI state, in which the terminal can be individually instructed by the base station to select a UL TCI state to apply to uplink transmission and a DL TCI state to apply to downlink reception. If the terminal is instructed to select a UL TCI state, the terminal can be instructed to select parameters to use as an uplink transmission beam or transmission filter using the reference RS or source RS configured in the UL TCI state. If the terminal is instructed to select a DL TCI state, the terminal can be instructed to select parameters to use for downlink channel estimation using the RS corresponding to qcl-Type1 configured in the DL TCI state, and to select parameters to use as a downlink reception beam or reception filter using the RS corresponding to qcl-Type2.

[0126] If the terminal is instructed with both the DL TCI state and the UL TCI state, the terminal can be instructed with parameters to be used as an uplink transmission beam or a transmission filter using the reference RS or source RS set in the corresponding UL TCI state, and can be instructed with parameters to be used for downlink channel estimation using the RS corresponding to qcl-Type1 set in the corresponding DL TCI state, and can be instructed with parameters to be used as a downlink reception beam or a reception filter using the RS corresponding to qcl-Type2. In this case, if the reference RS or source RS set in the DL TCI state and UL TCI state to which the terminal is instructed are different, the terminal can individually apply beams to uplink transmission and downlink reception, respectively, based on the instructed UL TCI state and DL TCI state.

[0127] A terminal can receive a joint TCI state from a base station for each bandwidth part within a specific cell through upper layer signaling up to 128 times, and among the separate TCI states, a DL TCI state can be set for each bandwidth part within a specific cell up to 64 or 128 times through upper layer signaling based on a terminal capability report. Among the separate TCI states, the DL TCI state and the joint TCI state can use the same upper layer signaling structure. For example, if 128 joint TCI states are set and 64 DL TCI states are set among the separate TCI states, the 64 DL TCI states can be included in the 128 joint TCI states.

[0128] Among the separate TCI states, the UL TCI state can be set to a maximum of 32 or 64 upper layer signaling for each specific bandwidth part within a specific cell based on the terminal capability report, and like the relationship between the DL TCI state and the joint TCI state among the separate TCI states, the UL TCI state and the joint TCI state among the separate TCI can also use the same upper layer signaling structure, and the UL TCI state among the separate TCI can use different upper layer signaling structures from the joint TCI state and the DL TCI state among the separate TCI states.

[0129] The use of different or identical upper layer signaling structures may be defined in the specification, or may be distinguished through another upper layer signaling established by the base station based on a terminal capability report containing information on which of the two usage modes the terminal can support.

[0130] The terminal can receive transmission and reception beam-related instructions in an integrated TCI manner using one of the joint TCI state and separate TCI state configured by the base station. The terminal can be configured by the base station via upper layer signaling whether to use either the joint TCI state or separate TCI state.

[0131] The terminal receives transmission / reception beam-related instructions using one of the methods selected from the joint TCI state and the separate TCI state through upper layer signaling. At this time, there may be two transmission / reception beam instruction methods from the base station: a MAC-CE-based instruction method and a MAC-CE-based activation and DCI-based instruction method.

[0132] If a terminal receives a transmission / reception beam-related instruction using a joint TCI state method through upper layer signaling, the terminal can perform a transmission / reception beam application operation by receiving a MAC-CE indicating the joint TCI state from a base station, and the base station can schedule reception of a PDSCH including the MAC-CE through a PDCCH for the terminal. If the MAC-CE includes one joint TCI state, the UE can use the indicated joint TCI state to determine the uplink transmission beam or transmission filter and the downlink reception beam or reception filter starting 3 ms after transmitting a PUCCH including HARQ-ACK information indicating whether reception of the PDSCH including the MAC-CE is successful. If the MAC-CE includes two or more joint TCI states, the UE can confirm that the multiple joint TCI states indicated by the MAC-CE correspond to each code point of the TCI state field of DCI format 1_1 or 1_2 starting 3 ms after transmitting a PUCCH including HARQ-ACK information indicating whether reception of the PDSCH including the MAC-CE is successful. Then, the UE can receive DCI format 1_1 or 1_2 and apply one joint TCI state indicated by the TCI state field in the corresponding DCI to the uplink transmission and downlink reception beams. At this time, DCI format 1_1 or 1_2 may or may not include downlink data channel scheduling information (with DL assignment) or may not include it (without DL assignment).

[0133] If a terminal receives an instruction related to a transmit / receive beam using a separate TCI state method through upper layer signaling, the terminal can perform a transmit / receive beam application operation by receiving a MAC-CE indicating a separate TCI state from a base station, and the base station can schedule reception of a PDSCH including the corresponding MAC-CE to the terminal through a PDCCH. If the MAC-CE includes only one set of separate TCI states, the terminal can determine an uplink transmit beam or transmit filter and a downlink receive beam or receive filter using the separate TCI states included in the indicated separate TCI state set starting from 3 ms after transmitting a PUCCH including HARQ-ACK information indicating whether reception of the corresponding PDSCH was successful. At this time, the separate TCI state set may mean single or multiple separate TCI states that one code point of the TCI state field in DCI format 1_1 or 1_2 can have, and one separate TCI state set may include one DL TCI state, one UL TCI state, or one DL TCI state and one UL TCI state. If there are two or more separate TCI state sets included in the MAC-CE, the UE may confirm that the multiple separate TCI state sets indicated by the MAC-CE correspond to each code point of the TCI state field of DCI format 1_1 or 1_2 starting from 3 ms after transmitting the PUCCH including HARQ-ACK information indicating whether reception for the corresponding PDSCH was successful, and may activate the indicated separate TCI state set.At this time, each code point of the TCI state field of DCI format 1_1 or 1_2 can indicate one DL TCI state, one UL TCI state, or one DL TCI state and one UL TCI state each. The terminal can receive DCI format 1_1 or 1_2 and apply a separate set of TCI states indicated by the TCI state field in the corresponding DCI to the uplink transmission and downlink reception beams. At this time, DCI format 1_1 or 1_2 may include downlink data channel scheduling information (with DL assignment) or may not include it (without DL assignment).

[0134] FIG. 5 is a diagram of a beam application time that can be considered when using an integrated TCI method in a wireless communication system according to an embodiment of the present disclosure.

[0135] As described above, the terminal may receive DCI format 1_1 or 1_2 from the base station, which includes (with DL assignment) or does not include (without DL assignment) downlink data channel scheduling information, and apply one joint TCI state or a separate set of TCI states indicated by the TCI state field in the corresponding DCI to the uplink transmission and downlink reception beams. Referring to FIG. 5,

[0136] - DCI format 1_1 or 1_2 with DL assignment (5-00): If the terminal receives DCI format 1_1 or 1_2 including downlink data channel scheduling information from the base station (5-01) and indicates one joint TCI state or a separate TCI state set based on the integrated TCI method, the terminal receives a PDSCH scheduled based on the received DCI (5-05), and can transmit a PUCCH including an HARQ-ACK indicating whether reception of the DCI and the PDSCH was successful (5-10). At this time, the HARQ-ACK can include the meaning of whether reception of both the DCI and the PDSCH was successful, and if at least one of the DCI and the PDSCH was not received, the terminal can transmit a NACK, and if reception of both was successful, the terminal can transmit an ACK.

[0137] - DCI format 1_1 or 1_2 without DL assignment (5-50): If the terminal receives DCI format 1_1 or 1_2 from the base station that does not include downlink data channel scheduling information and indicates one joint TCI state or a separate TCI state set based on the integrated TCI method (5-55), the terminal may assume at least one combination of the following for the DCI:

[0138] ■ Includes scrambled CRC using CS-RNTI.

[0139] ■ The value of all bits assigned to all fields used as RV (Redundancy Version) fields is 1.

[0140] ■ The value of all bits assigned to all fields used as MCS (Modulation and Coding Scheme) fields is 1.

[0141] ■ The value of all bits assigned to all fields used as NDI (New Data Indication) fields is 0.

[0142] ■ For FDRA (Frequency Domain Resource Allocation) Type 0, the value of all bits allocated to the FDRA field is 0, for FDRA Type 1, the value of all bits allocated to the FDRA field is 1, and when the FDRA method is dynamicSwitch, the value of all bits allocated to the FDRA field is 0.

[0143] The terminal can transmit a PUCCH including a HARQ-ACK indicating whether reception was successful for the DCI format 1_1 or 1_2 assuming the above-described matters (5-60).

[0144] - For both DCI format 1_1 or 1_2 with DL assignment (5-00) and without DL assignment (5-50), if the new TCI state indicated through DCI (5-01, 5-55) is the same as the TCI state that has already been indicated and applied to the uplink transmission and downlink reception beams, the terminal may maintain the previously applied TCI state, and if the new TCI state is different from the previously indicated TCI state, the terminal may determine the application time of the joint TCI state or separate TCI state set that can be indicated from the TCI state field included in the DCI as the time after the first slot (5-20, 5-70) after the time equivalent to BAT (beam application time, 5-15, 5-65) after the PUCCH transmission (5-30, 5-80), and up to (5-25, 5-75) before the corresponding slot (5-20, 5-70) TCI-state is available.

[0145] - For both DCI format 1_1 or 1_2 with DL assignment (5-00) and without DL assignment (5-50), BAT (5-15, 5-65) can be set by upper layer signaling based on terminal capability report information as a specific number of OFDM symbols, and the numerology for BAT and the first slot after BAT can be determined based on the smallest numerology among all cells to which the joint TCI state or separate TCI state set indicated through DCI is applied.

[0146] A terminal can apply one joint TCI state indicated via MAC-CE or DCI to reception of control resource sets connected to all terminal-specific search spaces, reception of PDSCHs scheduled as PDCCHs transmitted from the control resource sets, transmission of PUSCHs, and transmission of all PUCCH resources.

[0147] A terminal may apply one separate TCI state set, if one separate TCI state set indicated via MAC-CE or DCI includes one DL TCI state, to reception for control resource sets connected to all terminal-specific search spaces, to reception for PDSCH scheduled as PDCCH transmitted from the control resource set, and to all PUSCH and PUCCH resources based on the previously indicated UL TCI state.

[0148] A terminal can apply a separate TCI state set indicated via MAC-CE or DCI to all PUSCH and PUCCH resources if it includes one UL TCI state, and can apply it to reception of control resource sets connected to all terminal-specific search spaces based on previously indicated DL TCI states, and to reception of PDSCH scheduled as PDCCH transmitted from the corresponding control resource set.

[0149] When a separate set of TCI states indicated via MAC-CE or DCI includes one DL TCI state and one UL TCI state, the terminal may apply the DL TCI state to reception for all control resource sets associated with the terminal-specific search space and to reception for PDSCH scheduled as PDCCH transmitted from the control resource set, and may apply the UL TCI state to all PUSCH and PUCCH resources.

[0150] [Unified TCI state MAC-CE]

[0151] Hereinafter, a single TCI state indication and activation method based on the integrated TCI scheme is described. The terminal receives a PDSCH including the following MAC-CE from the base station, and from 3 slots after transmitting a HARQ-ACK for the corresponding PDSCH to the base station, the terminal can interpret each code point of the TCI state field in DCI format 1_1 or 1_2 based on the information in the MAC-CE received from the base station. That is, the terminal can activate each entry of the MAC-CE received from the base station to each code point of the TCI state field in DCI format 1_1 or 1_2.

[0152] FIG. 6 is a diagram illustrating another MAC-CE structure for activating and indicating a joint TCI state or a separate DL or UL TCI state in a wireless communication system according to an embodiment of the present disclosure.

[0153] Referring to Figure 6, the meaning of each field within the MAC-CE structure may be as follows.

[0154] - Serving Cell ID (6-00): This field can indicate which serving cell the MAC-CE is applied to. The length of this field can be 5 bits. If the serving cell indicated by this field is included in one or more of the upper layer signaling simultaneousU-TCI-UpdateList1, simultaneousU-TCI-UpdateList2, simultaneousU-TCI-UpdateList3, or simultaneousU-TCI-UpdateList4, the MAC-CE can be applied to all serving cells included in one or more of the lists simultaneousU-TCI-UpdateList1, simultaneousU-TCI-UpdateList2, simultaneousU-TCI-UpdateList3, or simultaneousU-TCI-UpdateList4 that include the serving cell indicated by this field.

[0155] - DL BWP ID (6-05): This field can indicate which DL BWP the corresponding MAC-CE applies to, and the meaning of each code point in this field can correspond to each code point of the bandwidth part indicator in the DCI. The length of this field can be 2 bits.

[0156] - UL BWP ID (6-10): This field can indicate which UL BWP the corresponding MAC-CE applies to, and the meaning of each code point in this field can correspond to each code point of the bandwidth part indicator in the DCI. The length of this field can be 2 bits.

[0157] - P i (6-15): This field can indicate whether each code point in the TCI state field in DCI format 1_1 or 1_2 has multiple TCI states or a single TCI state. If P i If the value of is 1, it means that the corresponding i-th code point has multiple TCI states, which may mean that the corresponding code point may contain separate DL TCI states and separate UL TCI states. If P i If the value is 0, it means that the corresponding ith code point has a single TCI state, which may mean that the corresponding code point may contain one of a joint TCI state, a separate DCI TCI state, or a separate UL TCI state.

[0158] - D / U (6-20): This field can indicate whether the TCI state ID field in the same octet is a joint TCI state, a separate DL TCI state, or a separate UL TCI state. If this field is 1, the TCI state ID field in the same octet can be a joint TCI state or a separate DL TCI state, and if this field is 0, the TCI state ID field in the same octet can be a separate UL TCI state.

[0159] - TCI state ID (6-25): This field can indicate a TCI state that can be identified by the upper layer signaling TCI-StateId. If the D / U field is set to 1, this field can be used to express the TCI-StateId, which can be expressed in 7 bits. If the D / U field is set to 0, the MSB (most significant bit) of this field can be considered a reserved bit, and the remaining 6 bits can be used to express the upper layer signaling UL-TCIState-Id. The maximum number of TCI states that can be activated can be 8 for a joint TCI state and 16 for separate DL or UL TCI states.

[0160] - R: Indicates reserved bit and can be set to 0.

[0161] For the MAC-CE structure of FIG. 6 described above, the terminal can include the third octet including the P1, P2, ..., P8 fields in FIG. 6 in the MAC-CE structure, regardless of whether unifiedTCI-StateType-r17 in MIMOparam-r17 in ServingCellConfig, which is an upper layer signaling, is set to joint or separate. In this case, the terminal can perform TCI state activation using the fixed MAC-CE structure regardless of the upper layer signaling set by the base station. As another example, for the MAC-CE structure of FIG. 6 described above, the terminal can omit the third octet including the P1, P2, ..., P8 fields in FIG. 6 when unifiedTCI-StateType-r17 in MIMOparam-r17 in ServingCellConfig, which is an upper layer signaling, is set to joint. In this case, the terminal can save up to 8 bits of the payload of the corresponding MAC-CE according to the upper layer signaling set by the base station. In addition, all D / U fields located from the fourth octet to the first bit in Fig. 6 can be regarded as R fields, and all corresponding R fields can be set to 0 bits.

[0162] [PDCCH: DCI related]

[0163] Next, we will specifically explain downlink control information (DCI) in 5G systems.

[0164] In a 5G system, scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) is transmitted from a base station to a terminal via DCI. The terminal can monitor a DCI format for fallback and a DCI format for non-fallback for the PUSCH or PDSCH. The fallback DCI format can be composed of fixed fields defined between the base station and the terminal, and the non-fallback DCI format can include configurable fields.

[0165] DCI can be transmitted through the Physical Downlink Control Channel (PDCCH) after going through the channel coding and modulation process. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC can be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs can be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly, but is included in the CRC calculation process. When the UE receives a DCI message transmitted on the PDCCH, it verifies the CRC using the assigned RNTI. If the CRC verification result is correct, the UE can determine that the message was transmitted to the UE.

[0166] For example, a DCI scheduling a PDSCH for System Information (SI) may be scrambled with SI-RNTI. A DCI scheduling a PDSCH for a Random Access Response (RAR) message may be scrambled with RA-RNTI. A DCI scheduling a PDSCH for a Paging message may be scrambled with P-RNTI. A DCI notifying a Slot Format Indicator (SFI) may be scrambled with SFI-RNTI. A DCI notifying a Transmit Power Control (TPC) may be scrambled with TPC-RNTI. A DCI scheduling a UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

[0167] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_0 with the CRC scrambled with C-RNTI can include, for example, the information in [Table 4] below.

[0168] [Table 4]

[0169]

[0170] DCI format 0_1 ​​can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_1 ​​with the CRC scrambled with C-RNTI can include, for example, the information in [Table 5] below.

[0171] [Table 5]

[0172]

[0173]

[0174] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_0 with the CRC scrambled with C-RNTI can include, for example, the information in [Table 6] below.

[0175] [Table 6]

[0176]

[0177] DCI format 1_1 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_1 with the CRC scrambled with C-RNTI can include, for example, the information in [Table 7] below.

[0178] [Table 7]

[0179]

[0180] [PDCCH: CORESET, REG, CCE, Search Space]

[0181] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0182] FIG. 7 is a diagram illustrating an example of a control region (Control Resource Set, CORESET) in which a downlink control channel is transmitted in a 5G wireless communication system.

[0183] FIG. 7 illustrates an example in which two control regions (Control Region #1 (701), Control Region #2 (702)) are set within a UE bandwidth part (710) in the frequency axis and within one slot (720) in the time axis. The control regions (701, 702) can be set to specific frequency resources (703) within the entire UE bandwidth part (710) in the frequency axis. The time axis can be set to one or more OFDM symbols, which can be defined as the control region length (Control Resource Set Duration, 704). Referring to the example illustrated in FIG. 7, Control Region #1 (701) is set to a control region length of two symbols, and Control Region #2 (702) is set to a control region length of one symbol.

[0184] In the aforementioned 5G, the control region can be established by the base station to the terminal via higher-layer signaling (e.g., system information, Master Information Block (MIB), Radio Resource Control (RRC) signaling). Establishing a control region for the terminal means providing information such as the control region identifier, the frequency location of the control region, and the symbol length of the control region. For example, this information may include the information in [Table 8] below.

[0185] [Table 8]

[0186]

[0187] In [Table 8], the tci-StatesPDCCH (simply named TCI (Transmission Configuration Indication) state) configuration information may include information on one or more SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) block indices or CSI-RS (Channel State Information Reference Signal) indices that are in a QCL (Quasi Co Located) relationship with the DMRS transmitted in the corresponding control region.

[0188] Figure 8 is a diagram showing an example of a basic unit of time and frequency resources that constitute a downlink control channel that can be used in 5G.

[0189] Referring to FIG. 8, the basic unit of time and frequency resources constituting the control channel can be referred to as a REG (Resource Element Group, 803), and the REG (803) can be defined as 1 OFDM symbol (801) on the time axis and 1 PRB (Physical Resource Block, 802) on the frequency axis, i.e., 12 subcarriers. The base station can concatenate REGs (803) to configure a downlink control channel allocation unit.

[0190] As illustrated in FIG. 8, if the basic unit to which a downlink control channel is allocated in 5G is called a CCE (Control Channel Element, 804), 1 CCE (804) can be composed of multiple REGs (803). Taking the REG (803) illustrated in FIG. 8 as an example, the REG (803) can be composed of 12 REs, and if 1 CCE (804) is composed of 6 REGs (803), 1 CCE (804) can be composed of 72 REs. When a downlink control region is set, the region can be composed of multiple CCEs (804), and a specific downlink control channel can be mapped to one or multiple CCEs (804) and transmitted according to the aggregation level (AL) within the control region. CCEs (804) within the control area are distinguished by numbers, and the numbers of the CCEs (804) can be assigned according to a logical mapping method.

[0191] The basic unit of the downlink control channel illustrated in FIG. 8, that is, the REG (803), may include both the REs to which the DCI is mapped and the areas to which the DMRS (805), which is a reference signal for decoding the REs, is mapped. As shown in FIG. 8, three DMRSs (805) may be transmitted within one REG (803). The number of CCEs required to transmit the PDCCH may be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and different numbers of CCEs may be used to implement link adaptation of the downlink control channel. For example, when AL = L, one downlink control channel may be transmitted through L CCEs. The terminal must detect a signal without knowing information about the downlink control channel, and a search space representing a set of CCEs is defined for blind decoding. A search space is a set of downlink control channel candidates (CCEs) that a terminal must attempt to decode at a given aggregation level. Since there are multiple aggregation levels, each of which can be a set of 1, 2, 4, 8, or 16 CCEs, a terminal can have multiple search spaces. A search space set can be defined as the set of search spaces at all configured aggregation levels.

[0192] Search spaces can be categorized into common search spaces and UE-specific search spaces. A certain group of UEs, or all UEs, can search the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling of system information or paging messages. For example, PDSCH scheduling allocation information for transmitting SIBs, including cell operator information, can be received by searching the common search space of the PDCCH. In the case of the common search space, since a certain group of UEs, or all UEs, must receive the PDCCH, it can be defined as a set of pre-arranged CCEs. Scheduling allocation information for UE-specific PDSCH or PUSCH can be received by searching the UE-specific search space of the PDCCH. The UE-specific search space can be defined UE-specifically as a function of the UE's identity and various system parameters.

[0193] In 5G, parameters for the search space for PDCCH can be configured from the base station to the terminal via higher layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station can configure the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the monitoring occasion for each symbol within the slot for the search space, the search space type (common search space or terminal-specific search space), the combination of DCI format and RNTI to be monitored in the corresponding search space, the control region index to be monitored for the search space, etc. to the terminal. For example, the information in [Table 9] below can be included.

[0194] [Table 9]

[0195]

[0196]

[0197] Depending on the configuration information, the base station may configure one or more search space sets for the terminal. In some embodiments, the base station may configure search space set 1 and search space set 2 for the terminal, and may configure the terminal to monitor DCI format A scrambled with X-RNTI in search space set 1 in a common search space, and may configure the terminal to monitor DCI format B scrambled with Y-RNTI in search space set 2 in a terminal-specific search space.

[0198] According to the configuration information, one or more search space sets may exist in a common search space or a terminal-specific search space. For example, search space set #1 and search space set #2 may be configured as a common search space, and search space set #3 and search space set #4 may be configured as terminal-specific search spaces.

[0199] In the common search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these.

[0200] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0201] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0202] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0203] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0204] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0205] In a terminal-specific search space, the following combinations of DCI formats and RNTIs can be monitored, although the examples below are not limited.

[0206] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0207] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0208] The RNTIs specified may follow the definitions and uses below.

[0209] C-RNTI (Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0210] TC-RNTI (Temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0211] CS-RNTI (Configured Scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0212] RA-RNTI (Random Access RNTI): Used for PDSCH scheduling in the random access phase.

[0213] P-RNTI (Paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0214] SI-RNTI (System Information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0215] INT-RNTI (Interruption RNTI): Used to indicate whether pucturing is in progress for PDSCH.

[0216] TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to indicate power control commands for PUSCH.

[0217] TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to indicate power control commands for PUCCH.

[0218] TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used to indicate power control commands for SRS.

[0219] The aforementioned specified DCI formats may follow the definitions in [Table 10] below.

[0220] [Table 10]

[0221]

[0222] In 5G, the search space of aggregation level L in the control region p and search space set s can be expressed as in [Mathematical Formula 1] below.

[0223] [Mathematical Formula 1]

[0224]

[0225] - : Integration level

[0226] - : Carrier Index

[0227] - : Total number of CCEs existing within the control region p

[0228] - : slot index

[0229] - : Number of PDCCH candidates for aggregation level L

[0230] - : PDCCH candidate index of aggregation level L

[0231] -

[0232] - , , , , ,

[0233] - : Terminal identifier

[0234] The value can be 0 for a common search space.

[0235] In the case of a terminal-specific search space, the value may correspond to a value that changes depending on the terminal's identity (C-RNTI or ID set to the terminal by the base station) and the time index.

[0236] In 5G, since multiple search space sets can be configured with different parameters (e.g., parameters in [Table 9]), the set of search space sets monitored by a terminal at each point in time can be different. For example, if search space set #1 is configured with an X-slot period and search space set #2 is configured with a Y-slot period and X and Y are different, the terminal can monitor both search space set #1 and search space set #2 in a specific slot, or can monitor either search space set #1 or search space set #2 in a specific slot.

[0237] [PUSCH: Transmission method related]

[0238] Next, we describe the scheduling method for PUSCH transmission. PUSCH transmission can be dynamically scheduled by the UL grant within the DCI or can operate by configured grant Type 1 or Type 2. Dynamic scheduling instructions for PUSCH transmission are possible in DCI format 0_0 or 0_1.

[0239] Configured grant Type 1 PUSCH transmission can be semi-statically configured by receiving configuredGrantConfig including rrc-ConfiguredUplinkGrant of [Table 11] through higher-level signaling, without receiving UL grant in DCI. Configured grant Type 2 PUSCH transmission can be semi-persistently scheduled by UL grant in DCI after receiving configuredGrantConfig not including rrc-ConfiguredUplinkGrant of [Table 11] through higher-level signaling. When PUSCH transmission operates by configured grant, parameters applied to PUSCH transmission are applied through configuredGrantConfig of higher-level signaling of [Table 11], except dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, scaling of UCI-OnPUSCH provided by pusch-Config of [Table 12]. If the terminal has been provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 11], the terminal applies tp-pi2BPSK in pusch-Config of [Table 12] to PUSCH transmission operated by the configured grant.

[0240] [Table 11]

[0241]

[0242]

[0243] Next, the PUSCH transmission method is described. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission can follow a codebook-based or non-codebook-based transmission method, respectively, depending on whether the value of txConfig in the upper signaling, pusch-Config in [Table 12], is 'codebook' or 'nonCodebook'.

[0244] As described above, PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, and can be semi-statically configured by configured grant. If the UE is instructed to schedule PUSCH transmission via DCI format 0_0, the UE performs beam configuration for PUSCH transmission using pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the activated uplink BWP within the serving cell, and the PUSCH transmission is based on a single antenna port. The UE does not expect scheduling for PUSCH transmission via DCI format 0_0 within a BWP where a PUCCH resource including pucch-spatialRelationInfo is not configured. If the UE does not configure txConfig in pusch-Config of [Table 12], the UE does not expect to be scheduled with DCI format 0_1.

[0245] [Table 12]

[0246]

[0247] Next, we describe codebook-based PUSCH transmission. Codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, or can operate semi-statically based on a configured grant. When codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or semi-statically configured via a configured grant, the UE determines a precoder for PUSCH transmission based on the SRS Resource Indicator (SRI), Transmission Precoding Matrix Indicator (TPMI), and transmission rank (the number of PUSCH transmission layers).

[0248] At this time, the SRI can be given through the SRS resource indicator field in the DCI or configured through the srs-ResourceIndicator higher-level signaling. The UE is configured with at least one SRS resource when transmitting a codebook-based PUSCH, and can be configured with up to two. When the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. In addition, the TPMI and transmission rank can be given through the precoding information and number of layers fields in the DCI or configured through the precodingAndNumberOfLayers higher-level signaling. The TPMI is used to indicate the precoder applied to the PUSCH transmission. If the UE is configured with one SRS resource, the TPMI is used to indicate the precoder to be applied to the configured one SRS resource. When a terminal is configured with multiple SRS resources, TPMI is used to indicate the precoder to be applied in the SRS resource indicated through SRI.

[0249] The precoder to be used for PUSCH transmission is selected from an uplink codebook having the same number of antenna ports as the nrofSRS-Ports value in the upper layer signaling, SRS-Config. In codebook-based PUSCH transmission, the UE determines the codebook subset based on the TPMI and codebookSubset in the upper layer signaling, pusch-Config. The codebookSubset in the upper layer signaling, pusch-Config, can be set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability reported by the UE to the base station. If the UE reported 'partialAndNonCoherent' as the UE capability, the UE does not expect the value of codebookSubset in the upper layer signaling to be set to 'fullyAndPartialAndNonCoherent'. Additionally, if the UE reports 'nonCoherent' as the UE capability, the UE does not expect the value of the upper signaling codebookSubset to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. If nrofSRS-Ports in the upper signaling SRS-ResourceSet points to two SRS antenna ports, the UE does not expect the value of the upper signaling codebookSubset to be set to 'partialAndNonCoherent'.

[0250] The terminal can be configured with one SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', and one SRS resource in the SRS resource set can be indicated via SRI. If multiple SRS resources are configured in the SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', the terminal expects that the value of nrofSRS-Ports in the upper signaling SRS-Resource is set to the same value for all SRS resources.

[0251] The terminal transmits to the base station one or more SRS resources included in the SRS resource set in which the usage value is set to 'codebook' according to upper signaling, and the base station selects one of the SRS resources transmitted by the terminal and instructs the terminal to perform PUSCH transmission using transmission beam information of the corresponding SRS resource. At this time, in codebook-based PUSCH transmission, the SRI is used as information for selecting an index of one SRS resource and is included in the DCI. Additionally, the base station includes in the DCI information indicating the TPMI and rank to be used by the terminal for PUSCH transmission. The terminal performs PUSCH transmission by applying the indicated rank and the precoder indicated by the TPMI based on the transmission beam of the corresponding SRS resource using the SRS resource indicated by the SRI.

[0252] Next, we describe non-codebook-based PUSCH transmission. Non-codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, and can operate semi-statically based on a configured grant. If at least one SRS resource is configured within an SRS resource set in which the usage value in the upper signaling, SRS-ResourceSet, is set to 'nonCodebook', the UE can be scheduled for non-codebook-based PUSCH transmission via DCI format 0_1.

[0253] For an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'nonCodebook', the UE can be configured with one connected NZP CSI-RS resource (non-zero power CSI-RS). The UE can perform calculations for a precoder for SRS transmission by measuring the NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the aperiodic SRS transmission at the UE is less than 42 symbols, the UE does not expect information about the precoder for SRS transmission to be updated.

[0254] If the value of resourceType in the upper signaling SRS-ResourceSet is set to 'aperiodic', the connected NZP CSI-RS is indicated by the SRS request field in DCI format 0_1 ​​or 1_1. At this time, if the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the presence of the connected NZP CSI-RS is indicated when the value of the SRS request field in DCI format 0_1 ​​or 1_1 is not '00'. At this time, the DCI must not indicate cross-carrier or cross BWP scheduling. In addition, if the value of the SRS request indicates the presence of an NZP CSI-RS, the NZP CSI-RS is located in the slot in which the PDCCH including the SRS request field is transmitted. At this time, the TCI states set for the scheduled subcarriers are not set to QCL-TypeD.

[0255] If a periodic or semi-persistent SRS resource set is configured, the associated NZP CSI-RS can be indicated through the associatedCSI-RS within the upper-level signaling SRS-ResourceSet. For non-codebook-based transmission, the UE does not expect the upper-level signaling spatialRelationInfo for the SRS resource and the associatedCSI-RS within the upper-level signaling SRS-ResourceSet to be configured together.

[0256] When multiple SRS resources are configured, the UE can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. At this time, the SRI can be indicated through the SRS resource indicator field in the DCI or can be set through the srs-ResourceIndicator, which is a higher-level signaling. Similar to the codebook-based PUSCH transmission described above, when the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. The UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be simultaneously transmitted in the same symbol within one SRS resource set and the maximum number of SRS resources are determined by the UE capability reported by the UE to the base station. At this time, the SRS resources that the UE simultaneously transmits occupy the same RB. The UE configures one SRS port for each SRS resource. Only one SRS resource set with the usage value set to 'nonCodebook' in the upper signaling SRS-ResourceSet can be set, and up to four SRS resources for non-codebook based PUSCH transmission can be set.

[0257] The base station transmits one NZP-CSI-RS associated with an SRS resource set to the terminal, and the terminal calculates a precoder to be used when transmitting one or more SRS resources within the SRS resource set based on the result measured upon reception of the NZP-CSI-RS. When the terminal transmits one or more SRS resources within the SRS resource set with usage set to 'nonCodebook' to the base station, the terminal applies the calculated precoder, and the base station selects one or more SRS resources from the received one or more SRS resources. At this time, in non-codebook based PUSCH transmission, the SRI represents an index that can express a combination of one or more SRS resources, and the SRI is included in the DCI. At this time, the number of SRS resources indicated by the SRI transmitted by the base station can be the number of transmission layers of the PUSCH, and the terminal transmits the PUSCH by applying the precoder applied to SRS resource transmission to each layer.

[0258] [PUSCH: Transmission Power Related]

[0259] As an example of the present disclosure, when uplink data is transmitted through an uplink data channel (PUSCH; Physical Uplink Shared Channel) in response to a power control command received from a base station, a method for transmitting by setting the transmission power of the uplink data channel by a terminal is described. The uplink data channel transmission power of the terminal can be determined as shown in [Mathematical Formula 2] below, expressed in dBm, together with the i-th transmission unit, the parameter set configuration index j, and the PUSCH power control adjustment state corresponding to the closed loop index l. In [Mathematical Formula 2] below, when the terminal supports multiple carrier frequencies in multiple cells, each parameter can be set for each cell c, each carrier frequency f, and each bandwidth part b, and can be distinguished by indices b, f, and c.

[0260] [Equation 2]

[0261]

[0262] - : The maximum transmission power available to the terminal in the i-th transmission unit is determined by the power class of the terminal, parameters activated from the base station, and various parameters built into the terminal.

[0263] - : Is and It consists of the sum of . is set to cell-specific upper layer signaling to the terminal, is a value set by terminal-specific upper layer signaling. Here, when j=0, it means PUSCH for transmitting msg3, when j=1, it means configured grant PUSCH, and when j={2, ...,J-1} is one of the values, it means grant PUSCH.

[0264] - : Subcarrier spacing configuration value

[0265] - : It may mean the amount of resources used in the i-th PUSCH transmission unit (e.g., the number of Resource Blocks (RBs) used for PUSCH transmission on the frequency axis).

[0266] - This refers to a value that can be determined (in the case of dynamic grant PUSCH) through upper layer settings and SRI (SRS Resource Indicator) as a value to compensate for path loss.

[0267] - : Pathloss is the path loss between the base station and the terminal, and the terminal uses the reference signal (RS) resource signaled by the base station. The path loss is calculated from the difference between the transmission power and the terminal reception signal level of the reference signal. The reference signal index is It refers to the downlink path loss estimate estimated by the terminal through the reference signal and the reference signal index. The UE can decide this via upper layer configuration and SRI (in case of dynamic grant PUSCH or configured grant PUSCH based on ConfiguredGrantConfig that does not include upper layer configuration rrc-ConfiguredUplinkGrant (type 2 configured grant PUSCH)) or via upper layer configuration.

[0268] - : It refers to a value determined according to the MCS (Modulation Coding Scheme) and the format of information transmitted via PUSCH (TF: transport format, e.g., whether UL-SCH is included or CSI is included, etc.).

[0269] - : Refers to a value for a closed loop index that can be determined by a higher layer setting and SRI for PUSCH as a closed loop power control adjustment value. Here, the closed loop power adjustment for PUSCH transmission can be supported by dividing into an accumulation method that accumulates and applies a value indicated by a TPC command and an absolute method that directly applies the value indicated by the TPC command, and this can be determined depending on whether the higher layer parameter tpc-Accumulation is set. If the higher layer parameter tpc-Accumulation is set to disabled, the closed loop power adjustment for PUSCH transmission is performed by the absolute method, and if tpc-Accumulation is not set, the closed loop power adjustment for PUSCH transmission is performed by the accumulation method.

[0270] PUSCH power control adjustment status can be determined through the bandwidth part b, carrier frequency f, cell c, i-th transmission unit, and closed loop index l.

[0271] - : A value indicated by a TPC command field included in DCI format 0_0, 0_1, or 0_2 that schedules the i-th PUSCH transmission unit corresponding to the closed loop index l within the bandwidth part b, carrier frequency f, and cell c, or a value indicated by a TPC command field included in DCI format 2_2 transmitted together with a CRC scrambled with TPC-PUSCH-RNTI.

[0272] o If the terminal has received the upper layer signaling twoPUSCH-PC-AdjustmentStates, the closed loop index l can have the value 0 or 1.

[0273] o If the terminal has not received the upper layer signaling twoPUSCH-PC-AdjustmentStates or has been scheduled for PUSCH transmission based on RAR UL grant, the closed loop index l may have a value of 0.

[0274] ● If the terminal has set ConfiguredGrantConfig, which is a higher layer signaling, and performs PUSCH transmission or retransmission, the closed loop index l can follow the powerControlLoopToUse value, which is a higher layer signaling.

[0275] ● If the terminal has been configured with the upper layer signaling SRI-PUSCH-PowerControl, the terminal can obtain a connection relationship between the value indicated by the SRI (SRS resource indicator) field in the DCI format that schedules PUSCH transmission and the closed loop index l configured through the upper layer signaling sri-PUSCH-ClosedLoopIndex, and can determine the closed loop index l based on the value indicated by the SRI field in the DCI format based on the connection relationship.

[0276] ● If the terminal is scheduled for PUSCH transmission based on a DCI format that does not include the SRI field, or if the upper layer signaling SRI-PUSCH-PowerControl is not set, the terminal may regard the closed loop index as 0.

[0277] ● If the terminal is indicated with a TPC command value through a TPC command field included in DCI format 2_2 transmitted with a CRC scrambled with TPC-PUSCH-RNTI, the closed loop index l can be indicated through the closed loop index field included in DCI format 2_2.

[0278] - If the terminal has not been set up with the upper layer signaling tpc-Accumulation, i.e., if the TPC command accumulation operation is possible for the terminal, the PUSCH power control adjustment state for the i-th PUSCH transmission unit corresponding to the closed loop index l within the bandwidth part b, carrier frequency f, and cell c. can be calculated as in [Mathematical Formula 3].

[0279] [Equation 3]

[0280]

[0281] o As described above, the TPC command field included in DCI format 0_0, 0_1, or 0_2 that schedules the m-th PUSCH transmission unit corresponding to the closed loop index l within the bandwidth part b, carrier frequency f, and cell c may be a value indicated by the TPC command field included in DCI format 2_2 transmitted together with the CRC scrambled with TPC-PUSCH-RNTI. If the TPC command accumulation operation is possible, The value may have a corresponding value in [dB] units depending on which value the TPC command field included in the DCI format 0_0, 0_1, 0_2, or 2_2 is indicated as in [Table 13] below. For example, if the value of the TPC command field is 0, can have a value of -1 dB.

[0282] o is a specific set of the TPC command values ​​described above. For all transmission units corresponding to mine can mean the sum of . At this time is a set It can mean the number of all elements belonging to me. may mean a set of DCIs including all TPC command values ​​for which a TPC command accumulation operation is to be performed for the i-th PUSCH transmission unit. To determine the starting point and the ending point in the time dimension, all DCIs received by the terminal within the two points are defined. can be included as an element of .

[0283] ● The end point for determining is from the start symbol of the i-th PUSCH transmission unit. It could be as far back as the symbol.

[0284] ● The starting point for deciding is From the start symbol of the th PUSCH transmission unit It can be a point as far back as the symbol. In this case, a positive integer is above The end point for determining (from the start symbol of the i-th PUSCH transmission unit) (as much as the previous point) than the symbol, From the start symbol of the th PUSCH transmission unit It can be determined as the smallest value that satisfies that the previous time point becomes an earlier time point in time by a symbol.

[0285] ● For example, The end point for determining can be defined as sym(i), From the start symbol of the th PUSCH transmission unit The time point before the symbol is sym( ), if sym(i) = sym(i-1) > sym(i- 2) > sym(i-3) holds, then i0 can be determined as 2.

[0286] - If the terminal has been set to the upper layer signaling tpc-Accumulation, i.e., if the TPC command accumulation operation is not possible for the terminal, the PUSCH power control adjustment state for the i-th PUSCH transmission unit corresponding to the closed loop index l within the bandwidth part b, carrier frequency f, and cell c. can be calculated as in [Mathematical Formula 3].

[0287] [Equation 4]

[0288]

[0289] o As described above, the TPC command field included in DCI format 0_0, 0_1, or 0_2 that schedules the i-th PUSCH transmission unit corresponding to the closed loop index l within the bandwidth part b, carrier frequency f, and cell c may be a value indicated by the TPC command field included in DCI format 2_2 transmitted together with the CRC scrambled with TPC-PUSCH-RNTI. If the TPC command accumulation operation is impossible, The value may have a corresponding value in [dB] units depending on which value the TPC command field included in the DCI format 0_0, 0_1, 0_2, or 2_2 is indicated as in [Table 13] below. For example, if the value of the TPC command field is 0, can have a value of -4 dB.

[0290] TPC command fieldAccumulated [dB]Absolute [dB]0-1-410-1211334

[0291] [PUSCH: TPMI Related]

[0292] Next, we describe the TPMI (Transmit Precoding Matrix Indicator) indicated by the base station through DCI during codebook-based PUSCH transmission.

[0293] If the terminal is scheduled for 1-layer transmission using a single PUSCH antenna port from the base station through DCI or higher layer signaling, the TPMI can be defined as W=1. Otherwise, that is, if the terminal receives 1-layer or more PUSCH scheduling using multiple PUSCH antenna ports from the base station through DCI or higher layer signaling, the TPMI W can be defined through [Table 14] to [Table 20] below.

[0294] [Table 14]

[0295]

[0296] The above [Table 14] shows the TPMI of 1 layer when the terminal has two PUSCH antenna ports. In the above [Table 14], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal to select one of TPMI index 0 and 1, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal to select one of TPMI index 0 to 5.

[0297] [Table 15]

[0298]

[0299] The above [Table 15] shows the TPMI for a 1-layer case where the terminal has 4 PUSCH antenna ports, transform precoding is used (i.e., DFTS-OFDM waveform is used). In the above [Table 15], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 3, if the terminal has a partial-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 11, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 27.

[0300] [Table 16]

[0301]

[0302] The above [Table 16] shows the TPMI for a 1-layer case where the terminal has 4 PUSCH antenna ports and no transform precoding is used (i.e., CP-OFDM waveform is used). In the above [Table 16], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 3, if the terminal has a partial-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 11, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indexes 0 to 27.

[0303] [Table 17]

[0304]

[0305] The above [Table 17] shows a 2-layer TPMI when a terminal has two PUSCH antenna ports, no transform precoding is used (i.e., a CP-OFDM waveform is used). In the above [Table 17], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal to select TPMI index 0, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal to select one of TPMI index 0 to 2.

[0306] [Table 18]

[0307]

[0308] The above [Table 18] shows a 2-layer TPMI when a terminal has 4 PUSCH antenna ports, no transform precoding is used (i.e., a CP-OFDM waveform is used). In the above [Table 18], if a terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indices 0 to 5, if a terminal has a partial-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indices 0 to 13, and if a terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station can select and instruct the terminal by one of TPMI indices 0 to 21.

[0309] [Table 19]

[0310]

[0311] The above [Table 19] shows a 3-layer TPMI when a terminal has 4 PUSCH antenna ports and no transform precoding is used (i.e., a CP-OFDM waveform is used). In the above [Table 19], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by TPMI index 0, if the terminal has a partial-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by one of TPMI indexes 0 to 2, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by one of TPMI indexes 0 to 6.

[0312] [Table 20]

[0313]

[0314] The above [Table 20] shows a 4-layer TPMI when a terminal has 4 PUSCH antenna ports and no transform precoding is used (i.e., a CP-OFDM waveform is used). In the above [Table 20], if the terminal has a non-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by TPMI index 0, if the terminal has a partial-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by one of TPMI indexes 0 to 2, and if the terminal has a full-coherent antenna structure and has reported the corresponding terminal capability to the base station, the base station may select and instruct the terminal by one of TPMI indexes 0 to 4.

[0315]

[0316] [SRS related]

[0317] Next, we describe an uplink channel estimation method using the Sounding Reference Signal (SRS) transmission of a terminal. The base station can configure at least one SRS configuration for each uplink BWP to convey configuration information for SRS transmission to the terminal, and can also configure at least one SRS resource set for each SRS configuration. For example, the base station and the terminal can exchange the following upper-level signaling information to convey information regarding the SRS resource set.

[0318] - srs-ResourceSetId: SRS resource set index

[0319] - srs-ResourceIdList: A set of SRS resource indices referenced in the SRS resource set.

[0320] - resourceType: This is the time axis transmission setting of the SRS resource referenced in the SRS resource set, and can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. If set to 'periodic' or 'semi-persistent', associated CSI-RS information can be provided depending on the usage of the SRS resource set. If set to 'aperiodic', an aperiodic SRS resource trigger list and slot offset information can be provided, and associated CSI-RS information can be provided depending on the usage of the SRS resource set.

[0321] - usage: This is a setting for the usage of the SRS resource referenced in the SRS resource set, and can be set to one of 'beamManagement', 'codebook', 'nonCodebook', and 'antennaSwitching'.

[0322] - alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter settings for adjusting the transmission power of the SRS resource referenced in the SRS resource set.

[0323] The terminal can understand that the SRS resource included in the set of SRS resource indices referenced in the SRS resource set follows the information set in the SRS resource set.

[0324] In addition, the base station and the terminal can transmit and receive upper layer signaling information to convey individual configuration information for the SRS resource. For example, the individual configuration information for the SRS resource can include time-frequency axis mapping information within the slot of the SRS resource, which can include information about frequency hopping within or between slots of the SRS resource. In addition, the individual configuration information for the SRS resource can include the time axis transmission configuration of the SRS resource, which can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. This can be restricted to have the same time axis transmission configuration as the SRS resource set including the SRS resource. If the time axis transmission configuration of the SRS resource is set to 'periodic' or 'semi-persistent', the SRS resource transmission period and slot offset (e.g., periodicityAndOffset) can additionally be included in the time axis transmission configuration.

[0325] The base station can activate, deactivate, or trigger SRS transmission to the UE through higher layer signaling, including RRC signaling or MAC CE signaling, or L1 signaling (e.g., DCI). For example, the base station can activate or deactivate periodic SRS transmission to the UE through higher layer signaling. The base station can instruct the UE to activate an SRS resource set with resourceType set to periodic through higher layer signaling, and the UE can transmit an SRS resource referenced in the activated SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and the slot mapping, including the transmission period and slot offset, follows the periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information set in the SRS resource, or the associated CSI-RS information set in the SRS resource set that includes the SRS resource. A terminal can transmit SRS resources within an activated uplink BWP for periodic SRS resources activated through upper layer signaling.

[0326] For example, a base station can activate or deactivate semi-persistent SRS transmission to a terminal through upper layer signaling. The base station can instruct the terminal to activate an SRS resource set through MAC CE signaling, and the terminal can transmit an SRS resource referenced in the activated SRS resource set. The SRS resource set activated through MAC CE signaling can be limited to an SRS resource set with resourceType set to semi-persistent. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource, and the slot mapping including the transmission period and slot offset follows the periodicityAndOffset configured in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information configured in the SRS resource, or the associated CSI-RS information configured in the SRS resource set that includes the SRS resource. If spatial relation info is configured in an SRS resource, the spatial domain transmission filter can be determined by referring to the configuration information for spatial relation info transmitted through MAC CE signaling that activates semi-persistent SRS transmission without following it. The terminal can transmit SRS resources within the activated uplink BWP for the semi-persistent SRS resource activated through upper layer signaling.

[0327] For example, a base station can trigger aperiodic SRS transmission to a terminal via DCI. The base station can indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) via the SRS request field of the DCI. The terminal can understand that an SRS resource set including the aperiodic SRS resource trigger indicated via DCI in the aperiodic SRS resource trigger list among the configuration information of the SRS resource set has been triggered. The terminal can transmit an SRS resource referenced in the triggered SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource. In addition, the slot mapping of the transmitted SRS resource can be determined through a slot offset between a PDCCH including the DCI and the SRS resource, which can refer to value(s) included in a slot offset set configured in the SRS resource set. Specifically, the slot offset between the PDCCH including DCI and the SRS resource can be applied by applying the value indicated in the time domain resource assignment field of the DCI among the offset value(s) included in the slot offset set configured in the SRS resource set. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information configured in the SRS resource, or can refer to the associated CSI-RS information configured in the SRS resource set including the SRS resource. The UE can transmit the SRS resource within the activated uplink BWP for the aperiodic SRS resource triggered through the DCI.

[0328] When a base station triggers aperiodic SRS transmission to a terminal through DCI, a minimum time interval may be required between a PDCCH including the DCI that triggers aperiodic SRS transmission and the SRS to be transmitted, so that the terminal can transmit the SRS by applying configuration information for the SRS resource. The time interval for SRS transmission of the terminal can be defined as the number of symbols between the last symbol of the PDCCH including the DCI that triggers aperiodic SRS transmission and the first symbol to which the first SRS resource to be transmitted among the SRS resource(s) is mapped. The minimum time interval can be determined with reference to the PUSCH preparation procedure time required for the terminal to prepare for PUSCH transmission. In addition, the minimum time interval can have different values ​​depending on the usage of the SRS resource set including the SRS resource to be transmitted. For example, the minimum time interval can be determined as N2 symbols, which are defined by considering the terminal processing ability according to the capability of the terminal with reference to the PUSCH preparation procedure time of the terminal. In addition, considering the usage of the SRS resource set including the SRS resource being transmitted, if the usage of the SRS resource set is set to 'codebook' or 'antennaSwitching', the minimum time interval can be set to N2 symbols, and if the usage of the SRS resource set is set to 'nonCodebook' or 'beamManagement', the minimum time interval can be set to N2+14 symbols.The terminal may transmit an aperiodic SRS if the time interval for aperiodic SRS transmission is greater than or equal to the minimum time interval, and may ignore the DCI that triggers the aperiodic SRS if the time interval for aperiodic SRS transmission is less than the minimum time interval.

[0329] SRS-Resource ::= SEQUENCE {srs-ResourceId SRS-ResourceId,nrofSRS-Ports ENUMERATED {port1, ports2, ports4},ptrs-PortIndex ENUMERATED {n0, n1} OPTIONAL, -- Need RtransmissionComb CHOICE {n2 SEQUENCE {combOffset-n2 INTEGER (0..1),cyclicShift-n2 INTEGER (0..7)},n4 SEQUENCE {combOffset-n4 INTEGER (0..3),cyclicShift-n4 INTEGER (0..11)}},resourceMapping SEQUENCE {startPosition INTEGER (0..5),nrofSymbols ENUMERATED {n1, n2, n4},repetitionFactor ENUMERATED {n1, n2, n4}},freqDomainPosition INTEGER (0..67),freqDomainShift INTEGER (0..268),freqHopping SEQUENCE {c-SRS INTEGER (0..63),b-SRS INTEGER (0..3),b-hop INTEGER (0..3)},groupOrSequenceHopping ENUMERATED { neither, groupHopping, sequenceHopping},resourceType CHOICE {aperiodic SEQUENCE {...},semi-persistent SEQUENCE {periodicityAndOffset-sp SRS-PeriodicityAndOffset,...},periodic SEQUENCE {periodicityAndOffset-p SRS-PeriodicityAndOffset,...}},sequenceId INTEGER (0..1023),spatialRelationInfo SRS-SpatialRelationInfo OPTIONAL, -- Need R...}

[0330] The spatialRelationInfo setting information in [Table 21] above refers to a single reference signal and applies the beam information of the reference signal to the beam used for the corresponding SRS transmission. For example, the spatialRelationInfo setting may include information such as [Table 22] below.

[0331] SRS-SpatialRelationInfo ::= SEQUENCE {servingCellId ServCellIndex OPTIONAL, -- Need SreferenceSignal CHOICE {ssb-Index SSB-Index,csi-RS-Index NZP-CSI-RS-ResourceId,srs SEQUENCE {resourceId SRS-ResourceId,uplinkBWP BWP-Id}}}

[0332] Referring to the above spatialRelationInfo setting, the index of the reference signal to be referenced in order to use the beam information of a specific reference signal, i.e., the SS / PBCH block index, CSI-RS index, or SRS index can be set. The upper signaling referenceSignal is setting information indicating which beam information of which reference signal is to be referenced for the corresponding SRS transmission, ssb-Index means the index of the SS / PBCH block, csi-RS-Index means the index of the CSI-RS, and srs means the index of the SRS, respectively. If the value of the upper signaling referenceSignal is set to 'ssb-Index', the terminal can apply the reception beam used when receiving the SS / PBCH block corresponding to the ssb-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'csi-RS-Index', the terminal can apply the reception beam used when receiving the CSI-RS corresponding to the csi-RS-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'srs', the terminal can apply the transmission beam used when transmitting the SRS corresponding to the srs as the transmission beam for the corresponding SRS transmission.

[0333] [SRS: Antenna switching]

[0334] Below, SRS for antenna switching is described.

[0335] The SRS transmitted from the terminal can be used by the base station to acquire DL CSI (Channel State Information) information (e.g., DL CSI acquisition). As a specific example, in a single cell or multi-cell (e.g., carrier aggregation (CA)) situation based on TDD (Time Division Duplex), the BS (Base Station) can schedule the transmission of SRS to the UE (User Equipment) and then measure the SRS transmitted from the UE. In this case, the base station can regard the uplink channel information estimated based on the SRS transmitted from the terminal as downlink channel information, assuming reciprocity between the DL (downlink) / UL (uplink) channels, and can perform downlink signal / channel scheduling for the terminal using this. In this case, the terminal can be configured to use antenna switching for the SRS for acquiring downlink channel information from the base station.

[0336] For example, according to the standard (e.g., 3gpp TS38.214), the usage of SRS can be set to the base station and / or terminal using a higher layer parameter (e.g., usage of RRC parameter SRS-ResourceSet). Here, the usage of SRS can be set to beam management usage, codebook transmission usage, non-codebook transmission usage, antenna switching usage, etc.

[0337] As described above, if the terminal receives the usage parameter in the upper layer signaling SRS-ResourceSet from the base station as 'antennaSwitching', the terminal can receive at least one upper layer signaling configuration from the base station according to the reported terminal capability. At this time, the terminal can report 'supportedSRS-TxPortSwitch' as ​​the terminal capability, and the value can be as follows. In the following, 'mTnR' can mean the terminal capability that supports transmission through m antennas and reception through n antennas.

[0338] - 't1r2': Terminal capability report value indicating that the terminal is capable of 1T2R operation.

[0339] - 't1r1-t1r2': Terminal capability report value indicating that the terminal is capable of 1T1R or 1T2R operation.

[0340] - 't2r4': Terminal capability report value indicating that the terminal is capable of 2T4R operation.

[0341] - 't1r4': Terminal capability report value indicating that the terminal is capable of 1T4R operation.

[0342] - 't1r6': Terminal capability report value indicating that the terminal is capable of 1T6R operation.

[0343] - 't1r8': Terminal capability report value indicating that the terminal is capable of 1T8R operation.

[0344] - 't2r6': Terminal capability report value indicating that the terminal is capable of 2T6R operation.

[0345] - 't2r8': Terminal capability report value indicating that the terminal is capable of 2T8R operation.

[0346] - 't4r8': Terminal capability report value indicating that the terminal is capable of 4T8R operation.

[0347] - 't1r1-t1r2-t1r4': Terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, or 1T4R operation.

[0348] - 't1r4-t2r4': Terminal capability report value indicating that the terminal is capable of 1T4R or 2T4R operation.

[0349] - 't1r1-t1r2-t2r2-t2r4': Terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, 2T2R, or 2T4R operation.

[0350] - 't1r1-t1r2-t2r2-t1r4-t2r4': Terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, 2T2R, 1T4R, or 2T4R operation.

[0351] - 't1r1': Terminal capability report value indicating that the terminal is capable of 1T1R operation.

[0352] - 't2r2': Terminal capability report value indicating that the terminal is capable of 2T2R operation.

[0353] - 't1r1-t2r2': Terminal capability report value indicating that the terminal is capable of 1T1R or 2T2R operation.

[0354] - 't4r4': Terminal capability report value indicating that the terminal is capable of 4T4R operation.

[0355] - 't1r1-t2r2-t4r4': Terminal capability report value indicating that the terminal is capable of 1T1R, 2T2R, or 4T4R operation.

[0356] When a terminal performs antenna switching, i.e., transmits different SRS resources connected to different antenna ports, the time interval between two adjacent SRS resources among all transmitted SRS resources may typically require approximately 15 μs. Taking this into account, a (minimum) guard period can be defined, as shown in [Table 23] below.

[0357] [Table 23]

[0358]

[0359] In [Table 23], μ represents numerology, represents the subcarrier spacing, and Y may mean the number of OFDM symbols representing the guard interval, i.e., the length of the guard interval. Referring to [Table 23], the guard interval may be set based on the parameter μ, which determines the numerology. In the guard interval, the terminal is set not to transmit any other signals, and the guard interval may be set to be used entirely for antenna switching.

[0360] For example, the guard interval may be set between the transmission times of two adjacent SRS resources, taking into account SRS resources transmitted at different OFDM symbol locations within the same slot.

[0361] As another example, if a terminal has two SRS resource sets configured for antenna switching purposes, and the two SRS resource sets are configured or triggered to be transmitted in two consecutive slots, and if the terminal reports the terminal capability to transmit SRS in all OFDM symbol positions within the slots, the terminal may expect that there will be a guard interval for antenna switching for at least Y OFDM symbols based on [Table 23] between the last OFDM symbol in which an SRS transmission is performed in the first slot in which an SRS transmission for the first SRS resource set is performed and the first OFDM symbol in which an SRS transmission is performed in the second slot in which an SRS transmission for the second SRS resource set is performed. That is, the time difference between two actual SRS transmissions may be greater than or equal to Y OFDM symbols.

[0362] - For such inter-slot guard intervals, similar to the guard interval between two SRS resources within the above-described slots, if the actual time difference between the last SRS transmission of the first slot and the first SRS transmission of the next slot within two consecutive slots is Y OFDM symbols, the terminal may not transmit any signal during the Y OFDM symbol interval.

[0363] - For such inter-slot guard intervals, if the actual time difference between the last SRS transmission of the first slot and the first SRS transmission of the next slot within two consecutive slots is Y OFDM symbols, and if all SRS transmissions before and after the inter-slot guard interval are dropped (cancelled) due to overlap with other signals, the terminal may determine that the inter-slot guard interval defined by Y OFDM symbols has been dropped (cancelled) by applying the same priority as the SRS transmissions before and after the guard interval, and if it is determined that it has been dropped, it may perform uplink transmission in this inter-slot guard interval.

[0364] For all antenna switching methods described above, the terminal can expect that all SRS resources within all SRS resource sets in which the upper layer signaling within the SRS resource set is set to 'antennaSwitching' from the base station will be configured with the same number of SRS ports.

[0365] For the antenna switching method based on the above-described 1T24, 1T4R, 2T4R, 1T6R, 1T8R, 2T6R, 2T8R, and 4T8R operations, the terminal may not expect that two or more SRS resource sets, of which the upper layer signaling usage from the base station is set to 'antennaSwitching', are set or triggered in the same slot.

[0366] For the antenna switching method based on the 1T1R, 2T2R, and 4T4R operations described above, the terminal may not expect that two or more SRS resource sets, in which the usage of the upper layer signaling from the base station is set to 'antennaSwitching', are set or triggered in the same OFDM symbol.

[0367] FIG. 9 is a diagram illustrating an SRS antenna switching operation according to an embodiment of the present disclosure.

[0368] Referring to FIG. 9, a terminal may be configured with two aperiodic SRS resource sets (e.g., SRS resource sets #0 and #1) when operating in 1T4R. The terminal may receive a PDCCH from a base station (900) and, through the PDCCH, may be instructed to initiate aperiodic SRS triggers for SRS resource set #0 (910) and SRS resource set #1 (920). At this time, a slot offset value for SRS resource set #0 (910) may be configured as slotOffset, which is a higher layer signaling, and the value may be 1, and aperiodic SRS transmission for SRS resource set #0 may be performed at a position 1 slot after the slot in which the PDCCH is received (i.e., at slot #1). Additionally, the slot offset value for SRS resource set #1 (920) can be set to slotOffset, which is a higher layer signaling, and the value is 2, so that aperiodic SRS transmission for SRS resource set #1 can be performed at a position 2 slots later than the slot in which the PDCCH is received (i.e., at slot #2).

[0369] SRS resource #0 (911) and SRS resource #1 (912) included in SRS resource set #0 (910) are transmitted at different OFDM symbol positions within slot #1, and at this time, Y number of OFDM symbols may exist as a guard interval between SRS resources #0 and #1 (913). In addition, when transmitting for SRS resource #0 (930), the terminal can perform SRS transmission by connecting one SRS port to the first receiving antenna port (935) of the terminal, and when transmitting for SRS resource #1 (940), the terminal can perform SRS transmission by connecting one SRS port to the second receiving antenna port (945) of the terminal.

[0370] SRS resource #2 (921) and SRS resource #3 (922) included in SRS resource set #1 (920) are transmitted at different OFDM symbol positions within slot #2, and Y number of OFDM symbols may exist as a guard interval between SRS resources #2 and #3 (923). In addition, when transmitting for SRS resource #2 (950), the terminal can perform SRS transmission by connecting one SRS port to the third receiving antenna port (955) of the terminal, and when transmitting for SRS resource #3 (960), the terminal can perform SRS transmission by connecting one SRS port to the fourth receiving antenna port (965) of the terminal.

[0371] By connecting the above-described four SRS resources #0 to #3 to different receiving antenna ports of terminals and transmitting SRS, the terminal can transmit SRS from all different receiving antenna ports so as to obtain channel information connected to all receiving antennas of the terminal, and through this, the base station can obtain channel information between the base station and the terminal and utilize it for uplink or downlink scheduling.

[0372] [Regarding terminal capability reporting]

[0373] In LTE and NR, a terminal, while connected to a serving base station, can perform a procedure to report its supported capabilities to the base station. In the description below, this is referred to as a UE capability report.

[0374] A base station can transmit a UE capability inquiry message requesting a capability report to a connected terminal. The message can include a UE capability request for each RAT (radio access technology) type of the base station. The RAT type-specific request can include information on a combination of supported frequency bands, etc. In addition, in the case of the UE capability inquiry message, UE capabilities for multiple RAT types can be requested through a single RRC message container transmitted by the base station, or the base station can include multiple UE capability inquiry messages including UE capability requests for each RAT type and transmit them to the terminal. That is, the UE capability inquiry can be repeated multiple times in one message, and the terminal can compose a corresponding UE capability information message and report it multiple times. In the next-generation mobile communication system, a UE capability request can be made for MR-DC (Multi-RAT dual connectivity), including NR, LTE, and EN-DC (E-UTRA - NR dual connectivity). Additionally, the terminal capability inquiry message is typically transmitted initially after the terminal is connected to the base station, but the base station may request it under any conditions when necessary.

[0375] In the above step, the terminal that receives the UE capability report request from the base station configures the terminal capability based on the RAT type and band information requested from the base station. Below is a summary of how the terminal configures the UE capability in the NR system.

[0376] 1. If the UE receives a list of LTE and / or NR bands through a UE capability request from the base station, the UE configures a band combination (BC) for EN-DC and NR stand-alone (SA). That is, it configures a candidate list of BCs for EN-DC and NR SA based on the bands requested to the base station via FreqBandList. Furthermore, the bands are prioritized in the order listed in FreqBandList.

[0377] 2. If the base station requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the UE completely removes NR SA BCs from the list of configured BC candidates. This operation can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0378] 3. The terminal then removes fallback BCs from the BC candidate list constructed in the above step. Here, a fallback BC is a BC obtained by removing at least one band corresponding to an SCell from a random BC. This step can be omitted because the BC before removing the band corresponding to at least one SCell can already cover the fallback BC. This step also applies to MR-DC, i.e., to LTE bands. The BCs remaining after this step are the final "candidate BC list."

[0379] 4. The terminal selects BCs to report by selecting BCs that match the requested RAT type from the final "candidate BC list" above. In this step, the terminal constructs the supportedBandCombinationList in a set order. That is, the terminal constructs BCs and UE capabilities to report according to the preset rat-Type order (nr -> eutra-nr -> eutra). In addition, it constructs a featureSetCombination for the constructed supportedBandCombinationList, and constructs a list of "candidate feature set combinations" from the candidate BC list after removing the list for the fallback BC (which contains capabilities of the same or lower level). The "candidate feature set combinations" above include feature set combinations for both NR and EUTRA-NR BCs, and can be obtained from the feature set combinations in the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0380] 5. Also, if the requested rat Type is eutra-nr and has an effect, featureSetCombinations are included in both containers: UE-MRDC-Capabilities and UE-NR-Capabilities. However, the NR feature set is included only in UE-NR-Capabilities.

[0381] After terminal capabilities are configured, the terminal transmits a terminal capability information message containing the terminal capabilities to the base station. Based on the terminal capabilities received from the terminal, the base station then performs appropriate scheduling and transmission / reception management for the terminal.

[0382] [PDSCH: TCI state activation MAC-CE]

[0383] Next, we will look at how to set up a beam for PDSCH.

[0384] Figure 10 illustrates a process for beam setting and activation of PDSCH.

[0385] Referring to FIG. 10, a list of TCI states for PDSCH can be indicated through a list of upper layers such as RRC (1000). The list of TCI states can be indicated, for example, as tci-StatesToAddModList and / or tci-StatesToReleaseList in the PDSCH-Config IE for each BWP. Next, some of the list of TCI states can be activated through MAC-CE (1020). The maximum number of activated TCI states can be determined according to the capability reported by the UE. One of the TCI states activated through MAC-CE can be indicated through DCI (1040). (1050) illustrates an example of a MAC-CE structure for PDSCH TCI state activation / deactivation. The MAC CE can include a serving cell identifier, a BWP ID, a TCI state identifier (Ti), and a CORESET Pool ID (1055).

[0386] [NC-JT related]

[0387] According to one embodiment of the present disclosure, Non-Coherent Joint Transmission (NC-JT) may be used for a terminal to receive PDSCH from multiple TRPs.

[0388] Unlike existing systems, 5G wireless communication systems can support not only services requiring high transmission speeds, but also services with very short transmission delays and high connection density. In a wireless communication network comprising multiple cells, transmission and reception points (TRPs), or beams, coordinated transmission between each cell, TRP, or / and beam can increase the signal strength received by a terminal or efficiently control interference between each cell, TRP, or / and beam, thereby satisfying diverse service requirements.

[0389] Joint Transmission (JT) is a representative transmission technology for the aforementioned cooperative communication, which increases the signal strength or processing rate received by a terminal by transmitting a signal to a single terminal through a number of different cells, TRPs, or / and beams. At this time, the channel between each cell, TRP, or / and beam and the terminal may have significantly different characteristics, and in particular, in the case of Non-Coherent Joint Transmission (NC-JT) that supports non-coherent precoding between each cell, TRP, or / and beam, individual precoding, MCS, resource allocation, TCI indication, etc. may be required depending on the channel characteristics of each link between each cell, TRP, or / and beam and the terminal.

[0390] The above-described NC-JT transmission can be applied to at least one channel among the downlink data channel (PDSCH), downlink control channel (PDCCH), uplink data channel (PUSCH), and uplink control channel (PUCCH). When transmitting PDSCH, transmission information such as precoding, MCS, resource allocation, and TCI are indicated as DL DCI, and for NC-JT transmission, the transmission information must be independently indicated for each cell, TRP, or / and beam. This is a major factor that increases the payload required for DL ​​DCI transmission, and this may adversely affect the reception performance of the PDCCH transmitting the DCI. Therefore, in order to support JT of PDSCH, it is necessary to carefully design a tradeoff between the amount of DCI information and the reception performance of control information.

[0391] FIG. 11 is a diagram illustrating an example of antenna port configuration and resource allocation for transmitting a PDSCH using cooperative communication in a wireless communication system according to an embodiment of the present disclosure.

[0392] Referring to FIG. 11, examples for PDSCH transmission are explained for each technique of joint transmission (JT), and examples for allocating radio resources for each TRP are shown.

[0393] (1100) of FIG. 11 is an example of coherent joint transmission (C-JT) that supports coherent precoding between each cell, TRP or / and beam.

[0394] In the case of C-JT, TRP A (1105) and TRP B (1110) transmit a single data (PDSCH) to the terminal (1115), and joint precoding can be performed on multiple TRPs. This may mean that DMRS is transmitted through the same DMRS ports for TRP A (1105) and TRP B (1110) to transmit the same PDSCH. For example, TRP A (1105) and TRP B (1110) may each transmit DRMS ​​to the terminal through DMRS port A and DMRS B. In this case, the terminal may receive one DCI information for receiving one PDSCH that is demodulated based on the DMRS transmitted through DMRS port A and DMRS B.

[0395] (1120) of FIG. 11 is an example of Non-Coherent Joint Transmission (NC-JT) that supports non-coherent precoding between each cell, TRP, or / and beam for PDSCH transmission.

[0396] In the case of NC-JT, PDSCH is transmitted to the terminal (1135) for each cell, TRP or / and beam, and individual precoding can be applied to each PDSCH. Each cell, TRP or / and beam transmits a different PDSCH or a different PDSCH layer to the terminal, thereby improving the throughput compared to single cell, TRP or / and beam transmission. In addition, each cell, TRP or / and beam repeatedly transmits the same PDSCH to the terminal, thereby improving the reliability compared to single cell, TRP or / and beam transmission. For convenience of explanation, cells, TRPs or / and beams are collectively referred to as TRPs hereinafter.

[0397] At this time, various wireless resource allocations can be considered, such as when the frequency and time resources used by multiple TRPs for PDSCH transmission are all the same (1140), when the frequency and time resources used by multiple TRPs do not overlap at all (1145), and when some of the frequency and time resources used by multiple TRPs overlap (1150).

[0398] To support NC-JT, DCIs of various forms, structures, and relationships can be considered to simultaneously allocate multiple PDSCHs to a single terminal.

[0399] FIG. 12 is a diagram illustrating an example of a configuration of downlink control information (DCI) for NC-JT in which each TRP transmits a different PDSCH or a different PDSCH layer to a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0400] Referring to FIG. 12, case #1 (1200) is an example in which, in addition to the serving TRP (TRP#0) used for single PDSCH transmission, (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)), and control information for PDSCHs transmitted from the (N-1) additional TRPs is transmitted independently from the control information for the PDSCHs transmitted from the serving TRP. That is, the terminal can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through independent DCIs (DCI#0 to DCI#(N-1)). The formats between the independent DCIs may be the same or different, and the payloads between the DCIs may also be the same or different. In the aforementioned case #1, each PDSCH control or allocation freedom can be fully guaranteed, but if each DCI is transmitted in different TRPs, coverage differences may occur for each DCI, which may deteriorate reception performance.

[0401] Case #2 (1205) shows an example in which, in addition to the serving TRP (TRP#0) used for single PDSCH transmission, (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)), control information (DCI) for the PDSCHs of the (N-1) additional TRPs is transmitted respectively, and each of these DCIs is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0402] For example, in the case of DCI#0, which is control information for a PDSCH transmitted from a serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, but in the case of shortened DCI (hereinafter, sDCI) (sDCI#0 to sDCI#(N-2)), which is control information for PDSCHs transmitted from cooperative TRPs (TRP#1 to TRP#(N-1)), it may include only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2. Therefore, in the case of sDCI, which transmits control information for PDSCHs transmitted from cooperative TRPs, since the payload is smaller than that of normal DCI (nDCI), which transmits PDSCH-related control information transmitted from a serving TRP, it is possible to include reserved bits compared to nDCI.

[0403] In the aforementioned case #2, the degree of freedom in controlling or allocating each PDSCH may be limited depending on the content of the information elements included in sDCI, but since the reception performance of sDCI is superior to that of nDCI, the probability of a difference in coverage by DCI may be reduced.

[0404] Case #3 (1210) shows an example in which, in a situation in which (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used for single PDSCH transmission, one control information for the PDSCHs of the (N-1) additional TRPs is transmitted, and this DCI is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0405] For example, in the case of DCI#0, which is control information for PDSCH transmitted from a serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, and in the case of control information for PDSCHs transmitted from cooperative TRPs (TRP#1 to TRP#(N-1)), it is possible to collect only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 into one 'secondary' DCI (sDCI) and transmit them. For example, the sDCI may include at least one piece of information among HARQ-related information such as frequency domain resource assignment, time domain resource assignment, and MCS of cooperative TRPs. In addition, for information not included in sDCI, such as BWP (bandwidth part) indicator or carrier indicator, the DCI (DCI#0, normal DCI, nDCI) of serving TRP can be followed.

[0406] Case #3 (1210) may limit the degree of freedom in controlling or allocating each PDSCH depending on the content of the information element included in sDCI, but it is possible to control the reception performance of sDCI and the complexity of blind decoding of DCI of the terminal may be reduced compared to case #1 (1200) or case #2 (1205).

[0407] Case #4 (1215) is an example of transmitting control information for PDSCHs transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in the same DCI (Long DCI) as the control information for PDSCHs transmitted from the serving TRP in a situation where (N-1) different PDSCHs are transmitted from (N-1) additional TRPs in addition to the serving TRP (TRP#0) used for single PDSCH transmission. That is, the UE can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. In case #4 (1215), the complexity of DCI blind decoding of the UE may not increase, but the degree of freedom in PDSCH control or allocation may be low, such as because the number of cooperative TRPs is limited due to the long DCI payload limitation.

[0408] In the following description and examples, sDCI may refer to various auxiliary DCIs, such as shortened DCI, secondary DCI, or normal DCI (DCI format 1_0 to 1_1 described above) containing PDSCH control information transmitted in a cooperative TRP, and unless a special limitation is specified, the description is similarly applicable to the various auxiliary DCIs described above.

[0409] In the following description and examples, the aforementioned cases #1 (1200), #2 (1205), and #3 (1210), in which more than one DCI (PDCCH) is used to support NC-JT, may be classified as multiple PDCCH-based NC-JT, and the aforementioned case #4 (1215), in which a single DCI (PDCCH) is used to support NC-JT, may be classified as single PDCCH-based NC-JT. In PDSCH transmission based on multiple PDCCH, a CORESET in which the DCI of the serving TRP (TRP#0) is scheduled and a CORESET in which the DCI of the cooperating TRPs (TRP#1 to TRP#(N-1)) are scheduled may be distinguished. As a method for distinguishing the CORESETs, there may be a method for distinguishing through an upper layer indicator for each CORESET, a method for distinguishing through beam setting for each CORESET, etc. Additionally, in single PDCCH-based NC-JT, instead of a single DCI scheduling multiple PDSCHs, a single PDSCH with multiple layers is scheduled, and the multiple layers described above can be transmitted from multiple Transmission Relays (TRPs). In this case, the connection relationship between a layer and the TRP transmitting the layer can be indicated through a Transmission Configuration Indicator (TCI) indication for the layer.

[0410] In the embodiments of the present disclosure, “cooperative TRP” may be replaced with various terms such as “cooperative panel” or “cooperative beam” in actual application.

[0411] In the embodiments of the present disclosure, “when NC-JT is applied” can be interpreted in various ways depending on the situation, such as “when a terminal simultaneously receives one or more PDSCHs in one BWP,” “when a terminal simultaneously receives PDSCHs based on two or more TCI (Transmission Configuration Indicator) indications in one BWP,” or “when a PDSCH received by a terminal is associated with one or more DMRS port groups,” but is used as a single expression for convenience of explanation.

[0412] The wireless protocol architecture for NC-JT in the present disclosure can be used in various ways depending on the TRP deployment scenario. For example, when there is no or small backhaul delay between cooperative TRPs, a method using a structure based on MAC layer multiplexing (CA-like method) similar to 410 of FIG. 4 is possible. On the other hand, when the backhaul delay between cooperative TRPs is so large that it cannot be ignored (for example, when more than 2 ms is required for information exchange such as CSI, scheduling, and HARQ-ACK between cooperative TRPs), a method (DC-like method) is possible to secure delay-robust characteristics by using an independent structure for each TRP starting from the RLC layer similar to 420 of FIG. 4.

[0413] A terminal supporting C-JT or / and NC-JT can receive C-JT or / and NC-JT related parameters or setting values ​​from a higher layer configuration, and set the RRC parameters of the terminal based on the parameters. For the higher layer configuration, the terminal can utilize a UE capability parameter, for example, tci-StatePDSCH. Here, the UE capability parameter, for example, tci-StatePDSCH, can define TCI states for the purpose of PDSCH transmission, and the number of TCI states can be set to 4, 8, 16, 32, 64, 128 in FR1, and to 64 and 128 in FR2, and among the set number, up to 8 states can be set that can be indicated by 3 bits of the TCI field of the DCI via a MAC CE message. The maximum value 128 means the value indicated by maxNumberConfiguredTCIstatesPerCC in the tci-StatePDSCH parameter included in the capability signaling of the terminal. In this way, a series of configuration processes from upper layer configuration to MAC CE configuration can be applied to a beamforming instruction or beamforming change command for at least one PDSCH in one TRP.

[0414] [Multi-DCI based Multi-TRP]

[0415] As one embodiment of the present disclosure, a multi-DCI-based multi-TRP transmission method is described. The multi-DCI-based multi-TRP transmission method can establish a downlink control channel for NC-JT transmission based on a multi-PDCCH.

[0416] In NC-JT based on multiple PDCCHs, when transmitting DCI for the PDSCH schedule of each TRP, a CORESET or search space can be distinguished for each TRP. The CORESET or search space for each TRP can be configured as in at least one of the following cases.

[0417] * Setting of upper layer index for each CORESET: The CORESET setting information set as an upper layer may include an index value, and the TRP transmitting the PDCCH in the corresponding CORESET may be distinguished by the set index value for each CORESET. That is, in a set of CORESETs with the same upper layer index value, it may be considered that the same TRP transmits the PDCCH, or it may be considered that a PDCCH scheduling the PDSCH of the same TRP is transmitted. The above-described index for each CORESET may be named as CORESETPoolIndex, and for CORESETs with the same CORESETPoolIndex value set, it may be considered that the PDCCH is transmitted from the same TRP. For a CORESET for which the CORESETPoolIndex value is not set, it may be considered that the default value of CORESETPoolIndex is set, and the above-described default value may be 0.

[0418] ** In the present disclosure, if the number of types of CORESETPoolIndex of each of the multiple CORESETs included in the upper layer signaling PDCCH-Config exceeds 1, i.e., if each CORESET has a different CORESETPoolIndex, the terminal may consider that the base station can use the multi-DCI based multi-TRP transmission method.

[0419] ** Differently, in the present disclosure, if each of the multiple CORESETs included in the upper layer signaling PDCCH-Config has only one type of CORESETPoolIndex, that is, if all CORESETs have the same CORESETPoolIndex of 0 or 1, the terminal can assume that the base station transmits using a single-TRP rather than using a multi-DCI based multi-TRP transmission method.

[0420] * Multiple PDCCH-Config settings: Multiple PDCCH-Configs are configured within one BWP, and each PDCCH-Config can include PDCCH settings for each TRP. That is, a list of CORESETs for each TRP and / or a list of search spaces for each TRP can be configured in one PDCCH-Config, and one or more CORESETs and one or more search spaces included in one PDCCH-Config can be considered to correspond to a specific TRP.

[0421] * CORESET Beam / Beam Group Configuration: The TRP corresponding to the CORESET can be distinguished through the beam or beam group configured for each CORESET. For example, if the same TCI state is set for multiple CORESETs, the CORESETs can be considered to be transmitted through the same TRP, or the PDCCH that schedules the PDSCH of the same TRP can be considered to be transmitted in the CORESET.

[0422] * Search space beam / beam group configuration: A beam or beam group is configured for each search space, and this allows TRPs for each search space to be distinguished. For example, if the same beam / beam group or TCI state is set for multiple search spaces, it can be considered that the same TRP transmits a PDCCH in the corresponding search space, or that a PDCCH that schedules the PDSCH of the same TRP is transmitted in the corresponding search space.

[0423] By dividing the CORESET or search space by TRP as described above, PDSCH and HARQ-ACK information classification for each TRP is possible, and this enables independent HARQ-ACK codebook generation and independent PUCCH resource use for each TRP.

[0424] The above settings can be independent on a per-cell or per-BWP basis. For example, a PCell may have two different CORESETPoolIndex values, while a specific SCell may not have a CORESETPoolIndex value set. In this case, it can be assumed that NC-JT transmission is configured on the PCell, while NC-JT transmission is not configured on the SCell without the CORESETPoolIndex value set.

[0425] The PDSCH TCI state activation / deactivation MAC-CE applicable to the multi-DCI based multi-TRP transmission method may follow the above-described FIG. 10. If the UE does not have CORESETPoolIndex set for each of all CORESETs in the upper layer signaling PDCCH-Config, the UE may ignore the CORESET Pool ID field (1055) in the corresponding MAC-CE (1050). If the UE can support the multi-DCI based multi-TRP transmission method, i.e., if each CORESET in the upper layer signaling PDCCH-Config of the UE has a different CORESETPoolIndex, the UE may activate the TCI state in the DCI included in the PDCCH transmitted in the CORESETs having the same CORESETPoolIndex value as the CORESET Pool ID field (1055) value in the corresponding MAC-CE (1050). For example, if the value of the CORESET Pool ID field (1055) within the MAC-CE (1050) is 0, the TCI state within the DCI included in the PDCCH transmitted from CORESETs with CORESETPoolIndex of 0 may follow the activation information of the MAC-CE.

[0426] When a terminal is configured to use a multi-DCI based multi-TRP transmission method from a base station, that is, when each of multiple CORESETs included in the upper layer signaling PDCCH-Config has more than one type of CORESETPoolIndex or when each CORESET has a different CORESETPoolIndex, the terminal can know that the following restrictions exist for PDSCHs scheduled from PDCCHs within each CORESET having two different CORESETPoolIndexes.

[0427] 1) If the PDSCHs indicated by the PDCCHs within each CORESET having two different CORESETPoolIndexes completely or partially overlap, the TCI states indicated by each PDCCH can be applied to different CDM groups. That is, two or more TCI states may not be applied to a single CDM group.

[0428] 2) The terminal can expect that the actual number of front-loaded DMRS symbols, the actual number of additional DMRS symbols, the location of actual DMRS symbols, and the DMRS type of each PDSCH will not be different when the PDSCHs indicated from the PDCCHs within each CORESET having two different CORESETPoolIndexes overlap completely or partially.

[0429] 3) The terminal can expect that the bandwidth portion indicated by the PDCCH within each CORESET having two different CORESETPoolIndexes will be the same and that the subcarrier spacing will also be the same.

[0430] 4) The terminal can expect that each PDCCH will fully contain information about the PDSCH scheduled from the PDCCH within each CORESET having two different CORESETPoolIndexes.

[0431] [Single-DCI based Multi-TRP]

[0432] As one embodiment of the present disclosure, a single-DCI-based multi-TRP transmission method is described. The single-DCI-based multi-TRP transmission method can establish a downlink control channel for NC-JT transmission based on a single-PDCCH.

[0433] In a single DCI-based multi-TRP transmission method, a PDSCH transmitted by multiple TRPs can be scheduled with a single DCI. At this time, the number of TCI states can be used as a method of indicating the number of TRPs transmitting the corresponding PDSCH. That is, if the number of TCI states indicated in the DCI scheduling the PDSCH is two, it can be considered as a single PDCCH-based NC-JT transmission, and if the number of TCI states is one, it can be considered as a single-TRP transmission. The TCI states indicated in the above DCI can correspond to one or both of the TCI states activated by MAC-CE. When the TCI states of the DCI correspond to two TCI states activated by MAC-CE, a correspondence relationship is established between the TCI codepoint indicated in the DCI and the TCI states activated by MAC-CE, and this can be the case when there are two TCI states activated by MAC-CE corresponding to the above TCI codepoint.

[0434] As another example, if at least one codepoint among all codepoints in the TCI state field within the DCI indicates two TCI states, the UE may assume that the base station can transmit based on the single-DCI based multi-TRP method. In this case, at least one codepoint indicating two TCI states within the TCI state field may be activated via the Enhanced PDSCH TCI state activation / deactivation MAC-CE.

[0435] Figure 13 is a diagram showing an Enhanced PDSCH TCI state activation / deactivation MAC-CE structure.

[0436] Referring to Figure 13, the meaning of each field in the Enhanced PDSCH TCI state activation / deactivation MAC CE and the values ​​that can be set in each field are as shown in [Table 24] below.

[0437] [Table 24]

[0438]

[0439] If the value of the C0 field (1305) is 1, the corresponding MAC-CE is the TCI state ID 0,1 Additionally, TCI state ID in field (1310) 0,2 It may include field (1315). This is the TCI state ID for the 0th codepoint of the TCI state field included in the DCI. 0,1 and TCI state ID 0,2 This means that the MAC-CE is activated, and if the base station instructs the terminal with the corresponding codepoint, the terminal can be instructed with two TCI states. If the value of the C0 field (1305) is 0, the corresponding MAC-CE is the TCI state ID. 0,2 It cannot contain field (1315), which is the TCI state ID for the 0th codepoint of the TCI state field contained within the DCI. 0,1 This means that one TCI state corresponding to is activated.

[0440] The above configuration can be independent on a per-cell or per-BWP basis. For example, a PCell may have up to two activated TCI states corresponding to a single TCI codepoint, while a specific SCell may have up to one activated TCI state corresponding to a single TCI codepoint. In this case, it can be assumed that NC-JT transmission is configured on the PCell, while NC-JT transmission is not configured on the aforementioned SCell.

[0441] [Distinguishing between Single-DCI-based Multi-TRP PDSCH Repetitive Transmission Techniques (TDM / FDM / SDM)]

[0442] Next, we describe a method for distinguishing between single-DCI-based multi-TRP PDSCH repetition transmission techniques. A UE may be instructed to use different single-DCI-based multi-TRP PDSCH repetition transmission techniques (e.g., TDM, FDM, SDM) based on the values ​​indicated by the DCI field from the base station and the upper layer signaling configuration. Table 25 below shows a method for distinguishing between single- and multiple-TRP-based techniques indicated to the UE based on the values ​​of specific DCI fields and the upper layer signaling configuration.

[0443] [Table 25]

[0444]

[0445] In the above [Table 25], each column can be explained as follows.

[0446] - Number of TCI states (2 columns): This refers to the number of TCI states indicated by the TCI state field in DCI, and can be 1 or 2.

[0447] - Number of CDM Groups (column 3): This indicates the number of different CDM groups of DMRS ports indicated by the Antenna port field in the DCI. It can be 1, 2, or 3.

[0448] - repetitionNumber setting and indication conditions (column 4): There are three conditions depending on whether repetitionNumber is set for all TDRA entries that can be indicated by the Time Domain Resource Allocation field in DCI and whether the actually indicated TDRA entry has repetitionNumber setting.

[0449] * Condition 1: At least one of all TDRA entries that can be indicated by the Time Domain Resource Allocation field contains a setting for repetitionNumber, and the TDRA entry indicated by the Time Domain Resource Allocation field in the DCI contains a setting for repetitionNumber greater than 1.

[0450] * Condition 2: At least one of all TDRA entries that can be indicated by the Time Domain Resource Allocation field contains a setting for repetitionNumber, and the TDRA entry indicated by the Time Domain Resource Allocation field in the DCI does not contain a setting for repetitionNumber.

[0451] * Condition 3: If all TDRA entries that can be indicated by the Time Domain Resource Allocation field do not contain a setting for repetitionNumber.

[0452] - RepetitionScheme setting related (column 5): This indicates whether the upper layer signaling repetitionScheme is set. The upper layer signaling repetitionScheme can be set to one of 'tdmSchemeA', 'fdmSchemeA', or 'fdmSchemeB'.

[0453] - Transmission technique indicated to the terminal (column 6): Refers to single or multiple TRP techniques indicated according to each combination (column 1) expressed in [Table 25] above.

[0454] * Single-TRP: This refers to a single TRP-based PDSCH transmission. If the UE has configured the pdsch-AggegationFactor in the upper layer signaling PDSCH-config, the UE can be scheduled for the configured number of repeated single-TRP-based PDSCH transmissions. Otherwise, the UE can be scheduled for a single single-TRP-based PDSCH transmission.

[0455] * Single-TRP TDM scheme B: This refers to PDSCH repeated transmission based on time resource division between single TRP slots. According to Condition 1 related to repetitionNumber described above, the UE repeatedly transmits PDSCH in the time dimension for the number of slots with repetitionNumber that is greater than 1 set in the TDRA entry indicated by the Time Domain Resource Allocation field. At this time, for each slot equal to the repetitionNumber number, the start symbol and symbol length of the PDSCH indicated by the TDRA entry are applied identically, and the same TCI state is applied for each PDSCH repeated transmission. This technique is similar to the slot aggregation method in that it performs PDSCH repeated transmission between slots on time resources, but it differs from slot aggregation in that it can dynamically determine whether to indicate repeated transmission based on the Time Domain Resource Allocation field in the DCI.

[0456] * Multi-TRP SDM: This refers to a PDSCH transmission method based on spatial resource division based on multiple TRPs. This is a method of receiving by dividing layers from each TRP. Although it is not a repetitive transmission method, it can increase the reliability of PDSCH transmission by increasing the number of layers and lowering the coding rate. The terminal can receive PDSCH by applying the two TCI states indicated through the TCI state field in the DCI for each of the two CDM groups indicated by the base station.

[0457] * Multi-TRP FDM scheme A: This refers to a multi-TRP based frequency resource division PDSCH transmission method. It has one PDSCH transmission position (occasion), so it is not repetitive transmission like multi-TRP SDM, but it is a technique that can transmit with high reliability by increasing the frequency resource amount and lowering the coding rate. Multi-TRP FDM scheme A can apply two TCI states indicated through the TCI state field in the DCI for non-overlapping frequency resources. If the PRB bundling size is determined as wideband, if the number of RBs indicated by the Frequency Domain Resource Allocation field is N, the terminal applies the first TCI state to the first ceil(N / 2) RBs and applies the second TCI state to the remaining floor(N / 2) RBs. Here, ceil(.) and floor(.) are operators that indicate rounding up and down to the first decimal place. If the PRB bundling size is determined as 2 or 4, even-numbered PRGs receive the first TCI state, and odd-numbered PRGs receive the second TCI state.

[0458] * Multi-TRP FDM scheme B: This refers to a multi-TRP based frequency resource division PDSCH repeated transmission method, and it has two PDSCH transmission positions (occasions) so that PDSCH can be repeatedly transmitted in each position. Multi-TRP FDM scheme B, like A, can apply two TCI states indicated through the TCI state field in the DCI to non-overlapping frequency resources. If the PRB bundling size is determined as wideband, if the number of RBs indicated by the Frequency Domain Resource Allocation field is N, the UE applies the first TCI state to the first ceil (N / 2) RBs and applies the second TCI state to the remaining floor (N / 2) RBs and receives them. Here, ceil (.) and floor (.) are operators indicating round up and down to the first decimal place. If the PRB bundling size is determined as 2 or 4, even-numbered PRGs receive the first TCI state, and odd-numbered PRGs receive the second TCI state.

[0459] * Multi-TRP TDM scheme A: This refers to a PDSCH repeated transmission method within a multi-TRP based time resource division slot. A terminal has two PDSCH transmission positions (occasions) within one slot, and the first reception position can be determined based on the starting symbol and symbol length of the PDSCH indicated through the Time Domain Resource Allocation field in the DCI. The starting symbol of the second reception position of the PDSCH can be a position that applies a symbol offset by the upper layer signaling StartingSymbolOffsetK from the last symbol of the first transmission position, and the transmission position can be determined by the indicated symbol length. If the upper layer signaling StartingSymbolOffsetK is not set, the symbol offset can be regarded as 0.

[0460] * Multi-TRP TDM scheme B: This refers to a PDSCH repeated transmission method between time resource division slots based on multiple TRPs. The UE has one PDSCH transmission position (occasion) in one slot, and can receive repeated transmissions based on the start symbol and symbol length of the same PDSCH for the number of slots indicated by the repetitionNumber through the Time Domain Resource Allocation field in the DCI. If the repetitionNumber is 2, the UE can receive the PDSCH repeated transmissions of the first and second slots by applying the first and second TCI states, respectively. If the repetitionNumber is greater than 2, the UE can use different TCI state application methods depending on how the upper layer signaling tciMapping is set. If tciMapping is set to cyclicMapping, the first and second TCI states are applied to the first and second PDSCH transmission positions, respectively, and the same TCI state application method is applied to the remaining PDSCH transmission positions. If tciMapping is set to sequentialMapping, the first TCI state is applied to the first and second PDSCH transmission positions, the second TCI state is applied to the third and fourth PDSCH transmission positions, and the same TCI state application method is applied to the remaining PDSCH transmission positions.

[0461] In the present disclosure below, upper signaling (or upper layer signaling) refers to a signal transmission method in which a base station transmits a signal to a terminal using a downlink data channel of a physical layer, or a terminal transmits a signal to a base station using an uplink data channel of a physical layer, and may also be referred to as RRC signaling, PDCP signaling, or a MAC (medium access control) control element (MAC control element; MAC CE).

[0462] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as having the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied have a specific format, or including a specific indicator that indicates whether cooperative communication is applied, or scrambled with a specific RNTI by the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied, or assuming cooperative communication is applied in a specific section indicated by a higher layer. For the convenience of the following description, the case where the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as the NC-JT case.

[0463] For convenience in the following description of the present disclosure, cells, transmission points, panels, beams, and / or transmission directions, which can be distinguished through upper layer / L1 parameters such as TCI state or spatial relation information, or indicators such as cell ID, TRP ID, and panel ID, may be uniformly described as TRP (transmission reception point), beam, or TCI state. Therefore, in actual application, TRP, beam, or TCI state can be appropriately replaced with one of the above terms.

[0464] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as having the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied have a specific format, or including a specific indicator that indicates whether cooperative communication is applied, or scrambled with a specific RNTI by the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied, or assuming cooperative communication is applied in a specific section indicated by a higher layer. For the convenience of the following description, the case where the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as the NC-JT case.

[0465] In the following description of the present disclosure, upper layer signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

[0466] - MIB (Master Information Block)

[0467] - SIB (System Information Block) or SIB

[0468] - RRC (Radio Resource Control)

[0469] - MAC (Medium Access Control) CE (Control Element)

[0470] In addition, L1 signaling may be signaling corresponding to at least one or a combination of one or more signaling methods using the physical layer channel or signaling below.

[0471] - PDCCH (Physical Downlink Control Channel)

[0472] - DCI (Downlink Control Information)

[0473] - UE-specific DCI

[0474] - Group common DCI

[0475] - Common DCI

[0476] - Scheduling DCI (e.g. DCI used for scheduling downlink or uplink data)

[0477] - Non-scheduled DCI (e.g. DCI not intended for scheduling downlink or uplink data)

[0478] - PUCCH (Physical Uplink Control Channel)

[0479] - UCI (Uplink Control Information)

[0480] In the present disclosure, determining the priority between A and B may be referred to in various ways, such as selecting a higher priority according to a predetermined priority rule and performing an action corresponding to it, or omitting or dropping an action for a lower priority.

[0481] The term slot used in the present disclosure below is a general term that may refer to a specific time unit corresponding to a TTI (Transmit Time Interval), and may specifically mean a slot used in a 5G NR system, or a slot or subframe used in a 4G LTE system.

[0482] In the following disclosure, the above examples are described through a number of embodiments, but they are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0483] As an example of the present disclosure, an uplink transmission and reception method between a terminal and a base station is described. When transmitting uplink data, the terminal may use a combination of at least one of the following [Method 1-1] to [Method 1-5].

[0484] [Method 1-1]

[0485] The terminal can use a method in which it independently determines and transmits information about the uplink precoder to use for uplink transmission without being instructed by the base station. In other words, the base station has no information about which uplink precoder the terminal used, and the base station can only instruct the terminal about the rank value transmitted through the uplink precoder, or the terminal can only perform transmission for a fixed rank value (for example, uplink transmission fixed to rank 1). In this case, the base station can know which uplink precoding the terminal used based on the channel estimated for the uplink demodulation reference signal (UL DMRS) transmitted by the terminal.

[0486] For this uplink transmission method, the terminal can perform uplink transmission by randomly selecting one or more uplink precoders fixedly defined in the standard. At this time, as described above, the terminal may select one of one or more uplink precoders corresponding to the rank indicated by the base station, or may select one of one or more uplink precoders corresponding to a fixed rank value. At this time, the rank value indicated by the base station or the fixed rank value can be notified to the terminal through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling from the base station. Alternatively, the fixed rank value can be fixedly defined in the standard.

[0487] For this uplink transmission method, if there is reciprocity between uplink and downlink channels, the terminal can receive a downlink reference signal (for example, CSI-RS) from the base station through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling, and can estimate a downlink channel based on the downlink reference signal and utilize the estimated downlink channel information. In addition, the terminal can calculate an uplink precoder based on the uplink channel information estimated from the downlink channel, and perform uplink transmission based on the calculated uplink precoder.

[0488] Through the above [Method 1-1], the terminal can perform uplink transmission without instruction information for the uplink precoder from the base station, thereby reducing the overhead of control information indicating scheduling information.

[0489] [Method 1-2]

[0490] A terminal and a base station can predefine one or more uplink precoders to be used during uplink transmission by the terminal. The base station can transmit to the terminal information about one uplink precoder to be used by the terminal, and the terminal can apply the corresponding uplink precoder during uplink transmission. The base station can estimate the uplink channel based on the uplink reference signal transmitted by the terminal, and determine an appropriate uplink precoder for the corresponding uplink channel to be used by the terminal among one or more predefined uplink precoders. For this method, the terminal and the base station can define an uplink precoder for each number of transmit antennas used by the terminal and each individual rank value that the terminal can support, and the base station can transmit to the terminal which uplink precoder to use based on downlink control information or upper layer signaling.

[0491] Through the above [Method 1-2], the terminal can secure scheduling flexibility from the perspective of the base station by directly receiving an uplink precoder to be used for uplink transmission from the base station, thereby determining whether to schedule only the terminal in question or to schedule other terminals together for any uplink radio resource to be utilized by the base station. That is, by confirming the correlation between the uplink channels of different terminals, if interference can be reduced between uplink transmissions between different terminals, the uplink precoders to be used by different terminals can be jointly determined so as not to interfere with each other; if there is no such pair of terminals, uplink scheduling for a single terminal can be allocated to the radio resource, and at this time, the uplink precoder to be used by a single terminal can be determined based on the uplink channel status between the terminal and the base station.

[0492] [Method 1-3]

[0493] The terminal and base station do not predefine the uplink precoders to be used during the terminal's uplink transmission. Instead, the terminal can receive a set of uplink precoders to be used from the base station. This transmission of the set of uplink precoders from the base station to the terminal can occur periodically, aperiodically upon additional instructions from the base station, or semi-continuously. The base station can receive an uplink reference signal from the terminal, estimate the uplink channel, and generate an uplink precoder suitable for the corresponding uplink channel.

[0494] - For example, when generating an uplink precoder, the base station can perform Singular Value Decomposition (SVD) on the uplink channel and determine the eigenvector corresponding to the main singular value of the uplink channel as the uplink precoder. In this case, the uplink channel can be defined as the uplink channel between the base station and the terminal for a specific frequency resource at a specific point in time.

[0495] - For example, the base station can perform SVD considering the uplink channel itself. For example, if the uplink channel in a specific RE or RB at a specific point in time between the base station and the terminal is defined as H, H can have as many rows as the number of receiving antennas of the base station (for example, N r,gNB ), can have as many columns as the number of transmitting antennas of the terminal (e.g. N t,UE ). At this time, the base station is N r,gNB x N t,UE By performing SVD on H, which is a matrix of size H can be decomposed into a product of three matrices, as shown in Fig. 1. In this case, U has a size of N. r,gNB x N r,gNB It can be a matrix of people, is of size N r,gNB x N t,UE may be a matrix, V has size N t,UE x N t,UE U and V can be unitary matrices in which the inner product between vectors corresponding to different columns becomes 0, and the inner product between vectors corresponding to the same column becomes 1. is min (N r,gNB , N t,UE) may be a matrix having as many singular values ​​as the number of diagonal elements. In the above, the uplink channel in a specific RE or RB at a specific point in time is defined as H, but H may also be defined by taking the average for one or more points in time and / or taking the average for one or more REs or RBs, and the method for taking the average may include, but is not limited to, the arithmetic mean, the geometric mean, the weighted mean, etc.

[0496] - For example, the base station can perform SVD considering the covariance matrix of the uplink channel. For example, if the uplink channel in a specific RE or RB at a specific point in time between the base station and the terminal is defined as H, the covariance matrix for this is can be calculated as follows. As described above, H is N r,gNB x N t,UE Since it is a matrix of size N, R is t,UE x N t,UE It can be a matrix of size, similar to the above where SVD is applied to the uplink channel. R can be decomposed into a product of three matrices, as follows. In this case, is of size N t,UE x N t,UE It can be a matrix of people, is of size N t,UE x N t,UE It can be a matrix of people, is of size N t,UE x N t,UE It can be a matrix. and It can be a unitary matrix in which the inner product between vectors corresponding to different columns becomes 0, and the inner product between vectors corresponding to the same column becomes 1. Silver N t,UEIt can be a matrix having as many singular values ​​as the number of diagonal elements. The covariance of the above uplink channel is defined based on the uplink channel H in a specific RE or RB at a specific point in time, but it can also be defined by taking the average for one or more points in time and / or taking the average for one or more REs or RBs, and the method of taking the average can include, but is not limited to, the arithmetic mean, the geometric mean, the weighted mean, etc.

[0497] - For example, when generating an uplink precoder, the base station can utilize a machine learning model that takes uplink channel information as input and an uplink precoder as output. When performing training on such a machine learning model, the base station can train the machine learning model by considering an arbitrary cost function. The cost function that can be considered at this time may include, but is not limited to, maximizing the uplink transmission throughput between the terminal and the base station or minimizing interference with signals of other terminals. The base station can train the machine learning model by receiving the uplink reference signal of the terminal, and if the output uplink precoder changes by a certain level or more while the machine learning model is trained in this way (for example, if the inner product between the uplink precoder already transmitted to the terminal and the newly generated uplink precoder is less than a certain value), the base station can transmit to the terminal a set of uplink precoders output through the machine learning model.

[0498] As described above, the uplink precoder generated by the base station can be generated and transmitted to the terminal through a combination of at least one of the following items.

[0499] - As an example, the uplink precoder generated by the base station as described above may be generated for each rank value that the terminal can support. For example, if the terminal can support up to rank 4 for uplink transmission, the base station may generate and transmit to the terminal an uplink precoder set including one or more uplink precoders corresponding to rank 1, one or more uplink precoders corresponding to rank 2, one or more uplink precoders corresponding to rank 3, and one or more uplink precoders corresponding to rank 4. In this case, if the terminal receives uplink scheduling information from the base station, the terminal may receive information about one of the uplink precoders. At this time, the amount of information required to instruct the terminal to the uplink precoder may be ceil(log2(N)) bits, where N is the number of all uplink precoders in the uplink precoder set received by the terminal, log2(.) may mean a logarithmic function with a base of 2, and ceil(.) may mean a rounding function.

[0500] - As an example, the uplink precoder generated by the base station as described above can be generated as a matrix having as many columns as the rank value that the terminal can support. For example, if the terminal can support up to rank 4 for uplink transmission, the base station can determine a matrix having as many rows as the number of transmission antennas of the terminal and 4 columns as one uplink precoder, and such one uplink precoder can be transmitted to the terminal. The terminal can consider that the vectors corresponding to different columns of this one uplink precoder are orthogonal or not orthogonal. In this case, if the terminal receives uplink scheduling information from the base station, the terminal can be instructed by the base station of a combination of columns for as many as the rank value among a total of 4 columns of the uplink precoder, and at this time, the amount of information required to instruct the terminal of the uplink precoder can be 4 bits, which is the same as the number of columns in the uplink precoder. This is the number of bits that can express the number of cases in which 1 of 4 columns is selected for rank 1, the number of cases in which 2 of 4 columns are selected for rank 2, the number of cases in which 3 of 4 columns are selected for rank 3, and the number of cases in which 4 of 4 columns are selected for rank 4. The terminal and the base station can generalize this and define that if the terminal can support up to rank N, it can represent the uplink precoder information that the terminal can use when receiving uplink scheduling information through N bits.

[0501] - As an example, the uplink precoder generated by the base station as described above can be generated as a matrix having as many columns as the rank values ​​that the terminal can support. For example, if the terminal can support up to rank 4 for uplink transmission, the base station can determine a matrix having as many rows as the number of transmission antennas of the terminal and 4 columns as one uplink precoder, and can transmit a set of uplink precoders including one or more such uplink precoders to the terminal. The terminal can consider that the vectors corresponding to different columns of each of the one or more uplink precoders are orthogonal or not orthogonal to each other. In this case, if the terminal receives uplink scheduling information from the base station, and if the terminal includes N uplink precoders in the uplink precoder set and each uplink precoder includes 4 columns, ceil(log2(N)) bits indicate which of the N uplink precoders is indicated, and an additional 4 bits may be required to indicate which one or more columns are indicated in the selected uplink precoder. This is the number of bits that can express all cases where 1 of 4 columns is selected for rank 1, 2 of 4 columns are selected for rank 2, 3 of 4 columns are selected for rank 3, and 4 of 4 columns are selected for rank 4. Generalizing this, the terminal and the base station can define which combination of 1 or more columns among M columns in a specific uplink precoder is indicated through M bits if the terminal can support up to rank M.

[0502] - As an example, the uplink precoder generated by the base station as above may be a vector having as many rows as the number of transmission antennas of the terminal. The base station may include one or more (for example, N) such vectors in the uplink precoder set and transmit them to the terminal. For example, if the terminal can support up to rank r for uplink transmission, the base station may select and transmit a vector with a rank value to be scheduled to the terminal among the N vectors. That is, the base station may calculate ceil(log2( )) can be used to indicate an uplink precoder, which can be defined as the number of bits that can express all cases of selecting 1 out of N uplink precoders (i.e., out of N vectors) in the case of rank 1 scheduling or selecting r out of N vectors in the case of rank r scheduling. In this case, can mean the number of cases in which k is selected out of N. At this time, different vectors can be considered to be orthogonal or not orthogonal. If different vectors are orthogonal to each other, it may be the case that the terminal uses the eigenvector corresponding to the singular value which is the result of performing SVD on the uplink precoder from the base station. This can prevent interference between layers when using the uplink channel by using the eigenvector corresponding to the singular value in the terminal and the base station respectively, so that the transmission throughput can be increased during uplink multiple input multiple output (MIMO) transmission. If different vectors are not orthogonal to each other, it may be the case that the base station generates a random uplink precoder. This can cause interference between layers with the uplink precoder itself. However, when the product of the uplink precoder and the uplink channel is called an effective uplink channel, if the uplink precoder is selected so that each column of the effective uplink channel is orthogonal, the final amount of interference can be minimized, which can be beneficial to the uplink transmission throughput. In such cases, a time difference occurs between the time when an uplink precoder is generated and the time when the uplink precoder is actually used for uplink transmission, and thus a problem that may arise due to a difference between the eigenvector obtained during SVD and the eigenvector of the uplink channel at the time of actual uplink transmission can be resolved.

[0503] FIG. 14 is a diagram illustrating an uplink transmission / reception method between a terminal and a base station according to an embodiment of the present disclosure. A terminal (1400) may transmit an uplink reference signal to a base station (1405) (1410). At this time, the terminal may transmit the uplink reference signal to the base station by considering at least one combination of methods including periodic, semi-persistent, aperiodic, or a method in which the terminal initiates transmission at its own discretion.

[0504] The base station can receive the uplink reference signal from the terminal, perform uplink channel estimation, and calculate an uplink precoder based on the uplink reference signal (1415). Furthermore, if reciprocity exists between the uplink and downlink channels, channel information measured through the uplink reference signal can also be used for downlink channel estimation and downlink precoder calculation.

[0505] The base station can transmit information about the calculated uplink precoder to the terminal (1420). The terminal stores the information and, if it has already received information from the base station, can update some or all of it (1425).

[0506] Thereafter, the base station can transmit uplink scheduling information to the terminal (1430). At this time, as part of the uplink scheduling information, the base station can transmit information to the terminal regarding whether to use the uplink precoder transmitted in step (1420), and if so, which of the transmitted uplink precoders to use (1430).

[0507] The terminal that received uplink scheduling information in the above step (1430) can perform uplink transmission based on the scheduling information (1435).

[0508] [Method 1-4]

[0509] The terminal and base station can use a method where the terminal calculates the uplink precoder to be used during uplink transmission, and the base station determines the final uplink precoder that achieves optimal reception performance. This uplink transmission method can be referred to as non-codebook-based uplink transmission.

[0510] FIG. 15 is a diagram illustrating a non-codebook based uplink transmission process according to one embodiment of the present disclosure.

[0511] Referring to FIG. 15, a terminal may receive an associated CSI-RS from a base station (1500). Based on the associated CSI-RS received from the base station, the terminal may estimate a channel between the base station and the terminal, and then calculate a precoder to be used for non-codebook-based PUSCH transmission based on the estimated channel (1510). At this time, the terminal may calculate the same precoder for all frequency resource regions for which it wishes to calculate a precoder, or may calculate different precoders for each partial frequency resource region. For example, the terminal may calculate a wideband precoder or a subband precoder. Thereafter, the terminal may apply a vector for each layer of the calculated overall precoding matrix to each SRS resource and transmit it to the base station (1520). The layer values ​​of the overall precoding matrix and the number of SRS resources may be determined based on the terminal capability report of the terminal and the upper layer signaling configuration of the base station (or at least one of the terminal capability report of the terminal and the upper layer signaling configuration of the base station). Accordingly, the terminal can simultaneously transmit to the base station one or more SRS resources to which the precoding matrix calculated by the terminal is applied by applying the vector for each layer of the entire precoding matrix consisting of up to eight layers to up to eight SRS resources.

[0512] The terminal may report to the base station the maximum number of SRS resources that can be simultaneously transmitted for one or more SRS resources to which a precoding matrix is ​​applied as the terminal capability. If the associated CSI-RS is an aperiodic CSI-RS and an SRS resource in an SRS resource set with usage set to non-codebook is an aperiodic SRS, the terminal may report the time interval from the time of receiving the associated CSI-RS from the base station to the time of transmission for one or more SRS resources to which precoding is applied. You can't expect anything less than 42 symbols. At this time, can be a value representing the subcarrier spacing. For example, the subcarrier spacing is It could be kHz.

[0513] Referring back to step 1510, if the associated CSI-RS is an aperiodic CSI-RS and an SRS resource in an SRS resource set with usage set to non-codebook is an aperiodic SRS, the terminal can estimate a channel based on the associated CSI-RS, compute a precoder, and use a time corresponding to at least 42 symbols to apply precoding to the SRS resource and transmit it (1510).

[0514] A base station that has received one or more SRS resources with precoding applied can determine a combination of SRS resources that is judged to have the best reception performance for each PUSCH precoding frequency resource unit. A combination of precoders applied to one or more SRS resources selected through the determined combination of SRS resources can be determined as a precoder of a terminal for non-codebook-based PUSCH transmission in the corresponding PUSCH precoding frequency resource unit (1530). The terminal can receive information about the combination of SRS resources determined by the base station from the base station through the SRI field in the DCI (1540). At this time, the terminal can understand the number of SRS resources indicated to the terminal through the SRI as rank information of a non-codebook-based PUSCH to be transmitted by the terminal, and can understand one or more SRS resources indicated to the terminal through the SRI as precoder information of a non-codebook-based PUSCH to be transmitted by the terminal. Based on the rank and precoder information, the terminal can perform non-codebook based PUSCH transmission (1550).

[0515] [Method 1-5]

[0516] Based on uplink scheduling information (e.g., a rank value) for a terminal, the terminal can calculate an uplink precoder and perform uplink transmission based on the uplink precoder. The terminal can be instructed about uplink scheduling information from a base station, and the instruction can be performed through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling. Along with the uplink scheduling information instruction, the terminal can be instructed about associated CSI-RS reception from the base station. The terminal can receive the associated CSI-RS and estimate a downlink channel based on it. If there is a correlation between the uplink channel and the downlink channel, the downlink channel information can be utilized as uplink channel information. Based on the acquired uplink channel information, the terminal can calculate an uplink precoder using the time and frequency resources and rank information included in the uplink scheduling information. The terminal can perform uplink transmission based on the uplink precoder.

[0517] The terminal can calculate an uplink precoder based on the downlink channel estimated by the terminal based on the correlation between the uplink channel and the downlink channel based on the above [Method 1-5] and apply it directly to the uplink transmission, thereby minimizing the delay time and performing high-performance uplink transmission.

[0518] The terminal may be notified of at least one method among the above [Method 1-1] to [Method 1-5] through a combination of at least one of the upper layer signaling, MAC-CE signaling, and L1-signaling from the base station, or may expect it to be fixedly defined in the standard.

[0519] - For example, one of the above [Method 1-2] and [Method 1-4] is set to the terminal through upper layer signaling, and the terminal can perform uplink transmission based on one of the two methods. If the terminal is not set to either [Method 1-2] or [Method 1-4], the terminal can be considered to operate based on [Method 1-2].

[0520] - As another example, one of the above [Method 1-2] and [Method 1-3] is set to the terminal through upper layer signaling, and the terminal can perform uplink transmission based on one of the two set methods. If the terminal is not set to either [Method 1-2] or [Method 1-3], the terminal can be considered to operate based on [Method 1-2].

[0521] - As another example, the terminal may expect to be configured via upper layer signaling for the above [Method 1-3]. If the terminal is not configured for the above [Method 1-3], the terminal may be assumed to operate based on the above [Method 1-1] or [Method 1-2].

[0522] - As another example, the terminal may expect that the above [Method 1-3] is fixedly defined in the standard.

[0523] Additionally, if the terminal is notified of a combination of at least one specific method from the base station through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling, this may mean that the terminal cannot support one or more other combinations of methods. For example, if the terminal supports one of [Method 1-2] and [Method 1-4] based on an upper layer signaling configuration, if the terminal has been configured with an upper layer signaling configuration from the base station for [Method 1-2], the terminal may be considered not to operate based on [Method 1-4].

[0524] The terminal may report to the base station the terminal capability that means that it can support at least one combination of [Method 1-1] to [Method 1-5]. In this case, if the terminal does not report the terminal capability that means that it can support at least one combination of [Method 1-1] to [Method 1-5], it may mean that the terminal supports a method other than the methods of the at least one combination reported by the terminal, or it may mean that it does not support any method of [Method 1-1] to [Method 1-5]. For example, if the terminal individually or only defines one terminal capability that means that it can support [Method 1-2] and [Method 1-3] and does not report this to the base station, the base station may regard this as reporting that the terminal does not support [Method 1-2] and [Method 1-3], but also supports [Method 1-1].

[0525] The terminal and base station may consider the following additional operations for the above [Method 1-3].

[0526] The terminal transmits an uplink reference signal to the base station, and the base station can measure the uplink channel based on this and generate a set of uplink precoders based on [Method 1-3] as described above. At this time, the base station can receive the uplink reference signal received from the terminal in different TRPs and individually estimate the uplink channel between each TRP and the terminal. For the uplink channel between the terminal and one or more TRPs, the base station can individually generate a set of uplink precoders that can be used when the terminal performs uplink transmission and receives in a single TRP, and a set of uplink precoders that can be used when the terminal performs uplink transmission and receives together in multiple TRPs, and can transmit information about the set of uplink precoders to the terminal.

[0527] - For example, if a terminal is connected to a base station including two TRPs, the terminal can transmit an uplink reference signal to the two TRPs. If the terminal operates in FR1 (frequency range 1), the terminal can commonly transmit one uplink reference signal to the first TRP and the second TRP, and the base station can estimate the channel between each TRP and the terminal based on the uplink reference signals received from the first TRP and the second TRP. If the terminal operates in FR2 (frequency range 2), the terminal can transmit at least two uplink reference signals so that the base station can measure the channel between the first TRP and the second TRP and the terminal. That is, the terminal can transmit the first uplink reference signal to the first TRP and the second uplink reference signal to the second TRP to estimate the channel between each TRP and the terminal.

[0528] - At this time, the base station may generate a set of uplink precoders for each channel by considering all of the first uplink channel between the first TRP and the terminal (for example, H1, where the number of rows is the number of receiving antennas of the first TRP and the number of columns is the number of transmitting antennas of the terminal), the second uplink channel between the second TRP and the terminal (for example, H2, where the number of rows is the number of receiving antennas of the second TRP and the number of columns is the number of transmitting antennas of the terminal), and the third uplink channel that may be considered when receiving uplink transmissions of the corresponding terminals together in the first TRP and the second TRP (for example, H3, where the number of rows is the sum of the number of receiving antennas of the first TRP and the number of receiving antennas of the second TRP and the number of columns is the number of transmitting antennas of the terminal). That is, the base station may generate a total of three sets of uplink precoders corresponding to H1, H2, and H3, respectively.

[0529] - The base station can transmit a set of such uplink precoders to the terminal, and when the terminal receives uplink scheduling information from the base station, the terminal can be instructed by the base station which uplink precoder set the uplink precoder indication information received by the terminal corresponds to.

[0530] - For example, the terminal can be instructed of an uplink precoder set to be referenced by the terminal through an uplink reference signal indicator field (e.g., SRS indicator field) in the downlink control information from the base station. For example, as described above, if the terminal operates in FR1, even though the terminal transmits to both the first TRP and the second TRP using one uplink reference signal, the terminal and the base station can define which uplink precoder set to use using this uplink reference signal indicator field. For example, the uplink reference signal indicator field can have as many bits as the number of TRPs. According to the example described above, the terminal can receive a 2-bit uplink reference signal indicator field from the base station, and each code point represented by the entire 2 bits can represent a specific uplink precoder set, and each bit of the field can mean whether an uplink channel is used between each TRP and the terminal for the corresponding uplink precoder set. For example, if the terminal receives a 2-bit uplink reference signal indicator field as "01", the terminal can understand that an uplink precoder set is indicated in which information about the uplink channel between the first TRP and the terminal has been used and information about the uplink channel between the second TRP and the terminal has not been used. That is, the terminal can understand that a first uplink precoder set generated based on the first uplink channel is indicated. For example, if the terminal receives a 2-bit uplink reference signal indicator field as "10", the terminal can understand that an uplink precoder set is indicated in which information about the uplink channel between the second TRP and the terminal has been used and information about the uplink channel between the first TRP and the terminal has not been used. That is, the terminal can understand that a second uplink precoder set generated based on the second uplink channel is indicated.For example, if the terminal receives a 2-bit uplink reference signal indicator field as "11", the terminal can understand that an uplink precoder set that uses both information about the uplink channel between the first TRP and the terminal and information about the uplink channel between the second TRP and the terminal is indicated. In other words, the terminal can understand that a third uplink precoder set generated based on the third uplink channel is indicated. The "00" value of the uplink reference signal indicator field can be ignored by the terminal or considered to be reserved.

[0531] - If the terminal operates in FR2, since the terminal uses two uplink reference signals to transmit to the first TRP and the second TRP respectively, the terminal can be informed of which uplink reference signal influenced the generation of the indicated uplink precoder set through the uplink reference signal indicator field. According to the example described above, the terminal can receive a 2-bit uplink reference signal indicator field from the base station, and each code point represented by the entire 2 bits can represent a specific uplink precoder set, and each bit of the field can mean whether each uplink reference signal is used. For example, if the terminal receives the 2-bit uplink reference signal indicator field as "01", the terminal can understand that the information about the first uplink channel estimated by the base station based on the first uplink reference signal was used, and the information about the second uplink channel estimated by the base station based on the second uplink reference signal was not used. That is, the terminal can understand that the first uplink precoder set generated based on the first uplink channel is indicated. For example, if the terminal receives a 2-bit uplink reference signal indicator field as "10", the terminal can understand that the information about the first uplink channel estimated by the base station based on the first uplink reference signal was not used and the information about the second uplink channel estimated by the base station based on the second uplink reference signal was used. That is, the terminal can understand that the second uplink precoder set generated based on the second uplink channel is indicated. For example, if the terminal receives a 2-bit uplink reference signal indicator field as "11", the terminal can understand that the third uplink precoder set generated based on the first uplink channel and the second uplink channel estimated by the base station based on the first uplink reference signal and the second uplink reference signal is indicated.The "00" value in the uplink reference signal indicator field can be ignored by the terminal or considered to be reserved.

[0532] Through the above-described method, the base station can directly instruct the terminal to use a cooperative reception method based on multiple TRPs. That is, the terminal can be instructed by the base station whether the corresponding uplink transmission is for a single TRP or for multiple TRPs.

[0533] The above-described method is not limited to two TRPs, and can be generalized and extended to M TRPs (M is a natural number). That is, an uplink reference signal indicator field of M bits can be used, and M can be set by the base station depending on how many TRPs the base station configures. If the terminal receives uplink scheduling information through downlink control information, when receiving it through two connected downlink control information, the terminal can be instructed on the number of TRPs in the first downlink control information, and can be instructed on information for selecting TRPs equal to the number of TRPs instructed in the first downlink control information from among all TRPs in the second downlink control information. Through this, robustness can be secured when receiving downlink control information by limiting the number of bits in the first downlink control information, and the second downlink control information can enable flexible scheduling information arrangement according to the field configuration in the first downlink control information.

[0534] A terminal can receive from a base station a set of uplink precoders that can be used during a specific time period. During the specific time period, the terminal can receive uplink precoder information to be applied to uplink transmission when receiving uplink scheduling information from the base station within a given uplink precoder set, without receiving an update on an additional uplink precoder set from the base station. In this case, the terminal can receive specific uplink precoder information within the uplink precoder set from the base station through downlink control information and perform uplink transmission based on the information.

[0535] After receiving an uplink precoder set from a base station, a terminal can be instructed through a single downlink control information which uplink precoders to apply during the current uplink scheduling and which uplink precoders to apply at a future time than the present. At this time, the multiple uplink precoders instructed to the terminal can be defined to be applied at specific times. That is, a first uplink precoder can be applied from a first start point to a first end point, and a second uplink precoder can be applied from a second start point to a second end point, and the first end point and the second start point can be the same or different. For example, the application time of the uplink precoder can be indicated together with the instruction for the uplink precoder through the downlink control information. Alternatively, information about the application time of the uplink precoder can be transmitted together when the base station transmits the set of uplink precoders to the terminal. The terminal can report to the base station as a terminal capability whether it supports dynamic switching method for uplink transmission for the single or multiple TRPs, and the base station can set corresponding upper layer signaling to the terminal.

[0536] The terminal can receive the uplink precoder set from the base station through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling.

[0537] - For example, the terminal can receive the first uplink precoder set through upper layer signaling. Until the terminal receives the first uplink precoder set through the upper layer signaling, the terminal can operate through a specific method (for example, [Method 1-2]) excluding [Method 1-3] among [Method 1-1] to [Method 1-5] when receiving uplink scheduling while transmitting an uplink reference signal to the base station. Thereafter, the terminal can update information about the initially indicated uplink precoder set through MAC-CE signaling or additional upper layer signaling.

[0538] - As another example, the terminal may be configured to operate in [Method 1-3] through upper layer signaling, and may receive a set of uplink precoders through MAC-CE signaling or update information about a set of uplink precoders already received. Until the terminal receives information about the set of uplink precoders through the first MAC-CE signaling, the terminal may operate in a specific method (for example, [Method 1-2]) among [Method 1-1] to [Method 1-5] except for [Method 1-3] when receiving uplink scheduling.

[0539] - As described above, when a terminal receives an uplink precoder set from a base station through upper layer signaling or MAC-CE signaling, the terminal may consider the number of complex numbers included in each uplink precoder matrix, and quantize and transmit each real part and imaginary part within the complex number into a specific number of bits. For example, if the number of transmit antennas of the terminal is Nt and the uplink precoder corresponds to rank r, the corresponding uplink precoder matrix may include a total of Nt xr complex numbers, and may include information on a total of Nt xr real parts and Nt xr imaginary parts. The base station may perform quantization of B bits for each real part and imaginary part, and in this case, 2 x Nt xr x B bits may be required per uplink precoder. This quantization may be performed separately on the real and imaginary parts, or on the phase and magnitude components of each complex number, and the same or different quantization bits may be used for the real and imaginary parts, phase and magnitude components.

[0540] The base station can instruct the terminal to apply one of the above [Method 1-1] to [Method 1-5] to the uplink transmission by instructing the terminal through downlink control information. For example, the terminal and the base station can define a new field in the downlink control information for instructing one of the above [Method 1-1] to [Method 1-5], and the terminal can be instructed by the base station through the new field for one of the above [Method 1-1] to [Method 1-5]. In this case, the uplink precoder indication field can be defined according to the method requiring the most bits for the uplink precoder information indication among the plurality of methods for the uplink precoder information that the terminal can be instructed to receive through the downlink control information. If a terminal receives uplink scheduling information through downlink control information, and receives it through two connected downlink control information, the first downlink control information may indicate one of the uplink transmission methods among [Method 1-1] to [Method 1-5], and the second downlink control information connected thereto may indicate an uplink precoder corresponding to the uplink transmission method indicated in the first downlink control information. Through this, robustness can be secured when receiving downlink control information by limiting the number of bits in the first downlink control information, and the second downlink control information may enable flexible scheduling information arrangement according to the field configuration in the first downlink control information. The terminal can report to the base station whether it supports a dynamic switching method between different uplink transmission methods as a terminal capability, and the base station can set a corresponding upper layer signaling to the terminal.

[0541] A terminal can receive an adjustment indicator for an uplink precoder from a base station. This adjustment indicator can be activated through a MAC-CE separate from the MAC-CE that activates the set of uplink precoders, or can be indicated to the terminal through downlink control information. Through this information, the base station can transmit signaling to the terminal to modify / update some information of an uplink precoder in the set of uplink precoders. The terminal can be indicated to an uplink precoder from the base station, and can receive real and imaginary part information corresponding to the number of complex numbers included in the uplink precoder, or information on a phase or magnitude component, through the adjustment indicator for the corresponding uplink precoder. When a terminal receives uplink scheduling information through downlink control information, if it receives it through two connected downlink control information, the first downlink control information may include information indicating whether an adjustment indicator for the uplink precoder is included in the second downlink control information, and if an indication is received through the first downlink control information that an adjustment indicator is included in the second downlink control information, the terminal may interpret the second downlink control information and apply the information indicated through the adjustment indicator for the uplink precoder to the uplink precoder that has been instructed to be applied to uplink scheduling, thereby confirming the final uplink precoder and applying it to uplink transmission. Through this, robustness can be secured when receiving downlink control information by limiting the number of bits in the first downlink control information, and the second downlink control information may enable flexible scheduling information arrangement according to the field configuration in the first downlink control information.

[0542] The terminal can report to the base station its capability to receive adjustment indicators for such uplink precoders, and by setting up corresponding upper layer signaling, it can be confirmed that the base station can deliver the adjustment indicators to the terminal.

[0543] FIG. 16 is a diagram showing the operation of a terminal according to an embodiment of the present disclosure.

[0544] In step 1600, the terminal may transmit terminal capability to the base station. At this time, the terminal capability signaling that can be received by the base station may be for a combination of at least one of the terminal capability indicating whether to support at least one of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5], the terminal capability indicating whether to support dynamic switching of an uplink transmission method corresponding to a single or multiple TRPs, the terminal capability indicating whether to be able to receive an adjustment indicator for an uplink precoder indicated by the base station, and the terminal capability indicating whether to support a dynamic switching method between at least one or more of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5]. In some cases, the above step 1600 may be omitted.

[0545] In step 1605, the terminal can receive upper layer signaling from the base station. At this time, the upper layer signaling that the terminal can set from the base station may be at least one combination of at least one of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5], upper layer signaling that the base station sets to support the terminal, upper layer signaling related to support of dynamic switching of an uplink transmission method corresponding to a single or multiple TRPs, upper layer signaling related to reception of an adjustment indicator for an uplink precoder indicated by the base station, and upper layer signaling related to a dynamic switching method among at least one or more of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5].

[0546] In step 1610, the terminal may transmit an uplink reference signal to the base station. At this time, the terminal may transmit the uplink reference signal as a single TRP, transmit a single uplink reference signal commonly to multiple TRPs, or transmit individual uplink reference signals corresponding to each TRP. For example, the transmission of the uplink reference signal may be performed based on information received through upper layer signaling.

[0547] In step 1615, the terminal may receive additional information from the base station. For example, if the terminal operates based on [Method 1-3], the additional information may be information about an uplink precoder set. For example, if the terminal operates based on [Method 1-4] or [Method 1-5], the additional information may be a downlink reference signal (e.g., CSI-RS).

[0548] In step 1620, the terminal may receive uplink scheduling information from the base station. At this time, the uplink scheduling information may include a combination of at least one of an uplink precoder, an adjustment indicator for the uplink precoder, an uplink reference signal indicator, and an uplink transmission method indicator, and as described above, the interpretation of the uplink precoder indicator and the uplink reference signal indicator may differ depending on which uplink transmission method is used. At this time, the uplink transmission method indicator may be a field that indicates dynamic switching among the methods supported by the terminal and the base station among [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5].

[0549] In step 1625, the terminal may perform uplink transmission to the base station. At this time, the terminal may perform uplink transmission based on uplink scheduling information including uplink precoder information received in step 1620.

[0550] The above flowchart illustrates an exemplary method that can be implemented according to the principles of the present disclosure, and various modifications may be made to the method illustrated in the flowchart herein. For example, although illustrated as a series of steps, various steps in each drawing may overlap, occur in parallel, occur in different orders, or occur multiple times. In other examples, steps may be omitted or replaced with other steps. For example, the order of each operation of step 1610 (transmitting an uplink reference signal by the terminal) and step 1615 (receiving additional information by the terminal) may be changed, and depending on the change in order, the reception accuracy of the uplink transmission transmitted by the terminal to the base station may vary.

[0551] FIG. 17 is a diagram illustrating the operation of a base station according to an embodiment of the present disclosure.

[0552] In step 1700, the base station can receive terminal capability from the terminal. At this time, the terminal capability signaling that can be received by the base station may be for a combination of at least one of the terminal capability indicating whether to support at least one of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5], the terminal capability indicating whether to support dynamic switching of an uplink transmission method corresponding to a single or multiple TRPs, the terminal capability indicating whether to be able to receive an adjustment indicator for an uplink precoder indicated by the base station, and the terminal capability indicating whether to support a dynamic switching method between at least one or more methods among the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5]. In some cases, the above step 1700 may be omitted.

[0553] In step 1705, the base station can transmit configuration information to the terminal through upper layer signaling according to the terminal capability reported by the terminal. At this time, the upper layer signaling that the base station can set for the terminal may be at least one combination of at least one of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5], upper layer signaling related to support for dynamic switching of uplink transmission methods corresponding to single or multiple TRPs, upper layer signaling related to reception of an adjustment indicator for an uplink precoder indicated by the base station, and upper layer signaling related to dynamic switching methods among at least one or more of the above [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5].

[0554] In step 1710, the base station may receive an uplink reference signal from the terminal. At this time, the base station may receive the uplink reference signal transmitted from the terminal in a single TRP, may commonly receive one uplink reference signal transmitted from the terminal in multiple TRPs, or may receive individual uplink reference signals corresponding to each TRP transmitted from the terminal in each TRP.

[0555] In step 1715, the base station may transmit additional information to the terminal. For example, if the terminal operates based on [Method 1-3], the additional information may be information about an uplink precoder set. For example, if the terminal operates based on [Method 1-4] or [Method 1-5], the additional information may be a downlink reference signal (e.g., CSI-RS).

[0556] In step 1720, the base station may transmit uplink scheduling information to the terminal. At this time, the uplink scheduling information may include a combination of at least one of an uplink precoder, an adjustment indicator for the uplink precoder, an uplink reference signal indicator, and an uplink transmission method indicator, and as described above, the interpretation of the uplink precoder indicator and the uplink reference signal indicator may differ depending on which uplink transmission method is used. At this time, the uplink transmission method indicator may be a field that indicates dynamic switching among the methods supported by the terminal and the base station among [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5].

[0557] In step 1725, the base station can receive an uplink transmission from the terminal. At this time, the base station can perform uplink reception based on uplink scheduling information including uplink precoder information transmitted in step 1720.

[0558] The above flowchart illustrates an exemplary method that can be implemented according to the principles of the present disclosure, and various modifications may be made to the method illustrated in the flowchart herein. For example, although illustrated as a series of steps, various steps in each drawing may overlap, occur in parallel, occur in different orders, or occur multiple times. In other examples, steps may be omitted or replaced with other steps. For example, the order of each operation of step 1710 (receiving an uplink reference signal from the base station) and step 1715 (transmitting additional information from the base station) may be changed, and depending on the change in order, the reception accuracy of the uplink transmission transmitted by the terminal to the base station may vary.

[0559] The proposed methods and / or embodiments of the present disclosure described above (e.g., [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and / or [Method 1-5], etc.) can be performed by the terminal of FIG. 18 and the base station of FIG. 19.

[0560] FIG. 18 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0561] Referring to FIG. 18, the terminal may include a transceiver, which refers to a terminal receiving unit (18-00) and a terminal transmitting unit (18-10), a memory (not shown), and a terminal processing unit (18-05, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver units (18-00, 18-10), the memory, and the terminal processing unit (18-05) of the terminal may operate. However, the components of the terminal are not limited to the examples described above. For example, the terminal may include more or fewer components than the components described above. In addition, the transceiver unit, the memory, and the processor may be implemented in the form of a single chip.

[0562] A transceiver unit can transmit and receive signals to and from a base station. The signals may include control information and data. To this end, the transceiver unit may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver unit, and the components of the transceiver unit are not limited to the RF transmitter and RF receiver.

[0563] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit a signal output from the processor through the wireless channel.

[0564] Memory can store programs and data necessary for the terminal's operation. Furthermore, memory can store control information or data included in signals transmitted and received by the terminal. Memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0565] Additionally, the processor may control a series of processes so that the terminal can operate according to the aforementioned embodiments. For example, the processor may control components of the terminal to perform uplink transmission based on at least one of [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5]. There may be multiple processors, and the processors may perform component control operations of the terminal by executing programs stored in memory.

[0566] FIG. 19 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0567] Referring to FIG. 19, the base station may include a transceiver, which refers to a base station receiver (19-00) and a base station transmitter (19-10), a memory (not shown), and a base station processing unit (19-05, or a base station control unit or processor). Depending on the communication method of the base station described above, the transceiver units (19-00, 19-10), the memory, and the base station processing unit (19-05) of the base station may operate. However, the components of the base station are not limited to the examples described above. For example, the base station may include more or fewer components than the components described above. In addition, the transceiver, the memory, and the processor may be implemented in the form of a single chip.

[0568] The transceiver can transmit and receive signals with the terminal. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0569] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit the signal output from the processor through the wireless channel.

[0570] The memory can store programs and data necessary for the operation of the base station. Furthermore, the memory can store control information or data included in signals transmitted and received by the base station. The memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0571] The processor may control a series of processes so that the base station can operate according to the embodiments of the present disclosure described above. For example, the processor may control each component of the base station to receive an uplink signal / channel from a terminal based on at least one of [Method 1-1], [Method 1-2], [Method 1-3], [Method 1-4], and [Method 1-5]. There may be a plurality of processors, and the processors may perform component control operations of the base station by executing a program stored in a memory.

[0572] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0573] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. The one or more programs include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of the present disclosure.

[0574] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc ROM (CD-ROM), digital versatile discs (DVDs) or other forms of optical storage device, magnetic cassette. Or, they may be stored in a memory configured as a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0575] Additionally, the program may be stored on an attachable storage device that is accessible via a communication network, such as the Internet, an intranet, a local area network (LAN), a wide local area network (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device performing an embodiment of the present disclosure.

[0576] In the specific embodiments of the present disclosure described above, components included in the invention are expressed in the singular or plural form, depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in the plural form may be composed of singular elements, or components expressed in the singular form may be composed of plural elements.

[0577] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are only specific examples to easily explain the technical contents of the present disclosure and help understand the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, the above-mentioned embodiments can be combined and operated with each other as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment can be combined with each other to operate a base station and a terminal. For example, parts of the first embodiment and the second embodiment of the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above-mentioned embodiments have been presented based on an FDD LTE system, other modifications based on the technical idea of ​​the above-mentioned embodiments can be implemented with other systems such as a TDD LTE system, 5G, or NR system.

[0578] Meanwhile, the order of description in the drawings explaining the method of the present invention does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

[0579] Alternatively, the drawings illustrating the method of the present invention may omit some components and include only some components within a scope that does not harm the essence of the present invention.

[0580] In addition, the method of the present invention may be implemented by combining some or all of the contents included in each embodiment within a scope that does not harm the essence of the invention.

[0581] Various embodiments of the present disclosure have been described above. The foregoing description of the present disclosure is for illustrative purposes only, and the embodiments of the present disclosure are not limited to the disclosed embodiments. Those skilled in the art will appreciate that the present disclosure can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present disclosure. The scope of the present disclosure is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present disclosure.

Claims

1. In a method performed by a terminal in a wireless communication system, A step of transmitting an uplink reference signal to a base station; A step of receiving uplink precoder information determined based on the uplink reference signal from the base station; A step of receiving scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information from the base station; and A method characterized by comprising a step of performing uplink transmission based on an uplink precoder indicated based on the above indicator.

2. In paragraph 1, The above uplink precoder information is: A method characterized in that the terminal includes at least one uplink precoder corresponding to each of the rank values ​​that the terminal can support.

3. In paragraph 1, The above uplink precoder information is: The terminal includes a matrix having columns corresponding to the maximum rank values ​​that can be supported, A method characterized in that the above scheduling information includes information indicating a combination of columns corresponding to the rank value of the terminal among the columns constituting the matrix.

4. In paragraph 1, If the base station includes multiple transmission reception points (TRPs), the uplink precoder information includes an uplink precoder set for each TRP, The above scheduling information includes a field indicating whether to use uplink precoder sets corresponding to each TRP, A method characterized in that the length of the above field is determined based on the number of the TRPs.

5. In a method performed by a base station in a wireless communication system, A step of receiving an uplink reference signal from a terminal; A step of performing estimation of an uplink channel based on the above uplink reference signal; A step of transmitting uplink precoder information determined based on the estimated uplink channel to the terminal; A step of transmitting scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information to the terminal; and A method characterized by comprising a step of receiving data from the terminal based on an uplink precoder indicated based on the above indicator.

6. In paragraph 5, The above uplink precoder information is: A method characterized in that the terminal includes at least one uplink precoder corresponding to each of the rank values ​​that the terminal can support.

7. In paragraph 5, The above uplink precoder information is: The terminal includes a matrix having columns corresponding to the maximum rank values ​​that can be supported, A method characterized in that the above scheduling information includes information indicating a combination of columns corresponding to the rank value of the terminal among the columns constituting the matrix.

8. In paragraph 5, If the base station includes multiple transmission reception points (TRPs), the uplink precoder information includes an uplink precoder set for each TRP, The above scheduling information includes a field indicating whether to use uplink precoder sets corresponding to each TRP, A method characterized in that the length of the above field is determined based on the number of the TRPs.

9. In a wireless communication system, at the terminal, At least one transceiver; At least one processor communicatively connected to said at least one transceiver; and Communicably connected to at least one processor, and executable individually or in any combination of the at least one processor, so that the terminal transmits an uplink reference signal to the base station, Receive uplink precoder information determined based on the uplink reference signal from the base station, Receive scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information from the base station, A memory storing a command to perform uplink transmission based on an uplink precoder indicated based on the above indicator; A terminal including .

10. In paragraph 9, The above uplink precoder information is: A terminal characterized in that the terminal includes at least one uplink precoder corresponding to each of the rank values ​​that the terminal can support.

11. In paragraph 9, The above uplink precoder information is: The terminal includes a matrix having columns corresponding to the maximum rank values ​​that can be supported, A terminal characterized in that the scheduling information includes information indicating a combination of columns corresponding to the rank value of the terminal among the columns constituting the matrix.

12. In paragraph 9, If the base station includes multiple transmission reception points (TRPs), the uplink precoder information includes an uplink precoder set for each TRP, The above scheduling information includes a field indicating whether to use uplink precoder sets corresponding to each TRP, A terminal characterized in that the length of the above field is determined based on the number of TRPs.

13. In a wireless communication system, at a base station, At least one transceiver; At least one processor communicatively connected to said at least one transceiver; and Communicably connected to at least one processor, and executable individually or in any combination of the at least one processor, such that the base station receives an uplink reference signal from the terminal, Estimation of the uplink channel is performed based on the above uplink reference signal, Transmitting uplink precoder information determined based on the above-mentioned estimated uplink channel to the terminal, Transmit scheduling information including an indicator indicating one of a plurality of uplink precoders included in the uplink precoder information to the terminal, A memory storing a command to receive data from the terminal based on an uplink precoder indicated based on the above indicator; A base station characterized by including:

14. In paragraph 13, The above uplink precoder information is: A base station characterized in that the terminal includes at least one uplink precoder corresponding to each of the rank values ​​that the terminal can support.

15. In paragraph 13, The above uplink precoder information is: The terminal includes a matrix having columns corresponding to the maximum rank values ​​that can be supported, The above scheduling information includes information indicating a combination of columns corresponding to the rank value of the terminal among the columns constituting the above matrix, If the base station includes multiple transmission reception points (TRPs), the uplink precoder information includes an uplink precoder set for each TRP, The above scheduling information includes a field indicating whether to use uplink precoder sets corresponding to each TRP, A base station, characterized in that the length of the above field is determined based on the number of TRPs.

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