Method and device for designing HARQ codebook according to terminal capability in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. More specifically, the present disclosure relates to a method performed by a terminal in a wireless communication system, the method comprising the steps of: transmitting, to a base station, capability information about the maximum number of physical downlink shared channels (PDSCHs) that can be received in a single slot by the terminal; receiving, from the base station, configuration information including first information including at least one slot offset value between each of reception slots of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook and second information about the maximum number of PDSCHs scheduled to a single slot; determining one or more reception slots of the PDSCHs on the basis of the first information; generating an HARQ-ACK codebook including pieces of HARQ-ACK information corresponding in number to the maximum number of PDSCHs that can be scheduled to each of the determined one or more reception slots of the PDSCHs on the basis of the second information, wherein the HARQ-ACK information is configured for each of the determined one or more reception slots of the PDSCHs; and transmitting the generated HARQ-ACK codebook to the base station.

Description

Method and device for designing HARQ codebook according to terminal capability in 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 HARQ-ACK, which indicates whether reception was successful when a terminal receives a physical downlink shared channel, 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 radio interface architecture / protocols is in progress for technologies such as intelligent factories (Industrial Internet of Things, IoT) 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 (CHO) 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] As described above and with the development of mobile communication systems, various services have become available, and methods for effectively providing these services are required.

[0009] The present disclosure seeks to provide a device and method capable of effectively providing a service in a mobile communication system.

[0010] In order to solve the above problems, the present disclosure provides a method performed by a terminal in a wireless communication system, the method comprising: transmitting, to a base station, capability information regarding a maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot; receiving, from the base station, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgment (HARQ-ACK) codebook and second information regarding a maximum number of PDSCHs scheduled in one slot; determining a reception slot of at least one PDSCH based on the first information; generating an HARQ-ACK codebook including a number of HARQ-ACK pieces of information corresponding to the maximum number of PDSCHs that can be scheduled in each of the determined reception slots of the at least one PDSCH based on the second information, wherein the HARQ-ACK information is configured for each of the determined reception slots of the at least one PDSCH; And it may include a step of transmitting the generated HARQ-ACK codebook to a base station.

[0011] A method performed by a base station in a wireless communication system, the method comprising: receiving, from a terminal, capability information regarding a maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot; transmitting, to the terminal, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and each transmission slot of a hybrid automatic repeat request acknowledgment (HARQ-ACK) codebook and second information regarding a maximum number of PDSCH opportunities scheduled in one slot; and receiving, from the terminal, a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled in each of the at least one PDSCH reception slots determined based on the first information, based on the second information, wherein the HARQ-ACK information can be configured for each of the determined reception slots of the at least one PDSCH.

[0012] In a wireless communication system, a terminal comprises: a transceiver; And a controller connected to the transceiver, wherein the controller: transmits capability information about the maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot to a base station, receives configuration information from the base station, first information including at least one slot offset value between each reception slot of at least one PDSCH and each transmission slot of a hybrid automatic repeat request acknowledgment (HARQ-ACK) codebook, and second information about the maximum number of PDSCHs scheduled in one slot, determines a reception slot of at least one PDSCH based on the first information, and generates a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled in each of the determined reception slots of the at least one PDSCH based on the second information, wherein the HARQ-ACK information is configured for each of the determined reception slots of the at least one PDSCH, and transmits the generated HARQ-ACK codebook to the base station.

[0013] In a wireless communication system, a base station comprises: a transceiver; and a controller connected to the transceiver, wherein the controller is configured to: receive, from a terminal, capability information regarding a maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot; transmit, to the terminal, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and each transmission slot of a hybrid automatic repeat request acknowledgment (HARQ-ACK) codebook and second information regarding a maximum number of PDSCH opportunities scheduled in one slot; and receive, from the terminal, a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled in each of the at least one PDSCH reception slots determined based on the first information, based on the second information, wherein the HARQ-ACK information can be configured for each reception slot of the at least one PDSCH determined.

[0014] The disclosed embodiment can provide a device and method capable of effectively providing a service in a mobile communication system.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] FIG. 4 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.

[0019] FIG. 5 is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0020] FIG. 6 is a diagram for explaining a method for a base station and a terminal to transmit and receive data by taking into account downlink data channels and rate matching resources according to one embodiment of the present disclosure.

[0021] FIG. 7 is a diagram illustrating an example of frequency axis resource allocation of a physical downlink shared channel (PDSCH) in a wireless communication system according to one embodiment of the present disclosure.

[0022] FIG. 8 is a diagram illustrating an example of time axis resource allocation of PDSCH in a wireless communication system according to one embodiment of the present disclosure.

[0023] FIG. 9 is a diagram illustrating an example of time axis resource allocation according to subcarrier spacing of a data channel and a control channel in a wireless communication system according to one embodiment of the present disclosure.

[0024] FIG. 10 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, or dual connectivity situation according to one embodiment of the present disclosure.

[0025] FIG. 11a, FIG. 11b, and FIG. 11c are diagrams illustrating a Type-1 HARQ-ACK codebook for HARQ-ACK transmission of PDSCH according to one embodiment of the present disclosure.

[0026] FIG. 12a and FIG. 12b are diagrams illustrating HARQ-ACK codebook generation according to terminal capabilities according to one embodiment of the present disclosure.

[0027] FIG. 13 is a diagram showing a terminal according to one embodiment of the present disclosure receiving two or more PDSCHs with the same index in one slot.

[0028] FIG. 14 is a diagram illustrating a change in a HARQ-ACK codebook according to the maximum number of PDSCHs that can be processed in one slot according to one embodiment of the present disclosure.

[0029] FIG. 15 illustrates a flowchart for generating a HARQ-ACK codebook according to terminal capabilities according to one embodiment of the present disclosure.

[0030] FIG. 16 is a flowchart for selecting a HARQ-ACK codebook type according to one embodiment of the present disclosure.

[0031] FIG. 17 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0032] FIG. 18 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0033] To meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems, efforts are being made to develop improved 5G communication systems, or pre-5G communication systems. For this reason, 5G communication systems, or pre-5G communication systems, are also called beyond 4G networks or post-LTE systems. To achieve high data rates, 5G communication systems are being considered for implementation in ultra-high frequency (mmWave) bands (e.g., 60 GHz bands). To mitigate radio path loss and increase the transmission range of radio waves in ultra-high frequency bands, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large-scale antenna technologies are being discussed in 5G communication systems. In addition, to improve the network of the system, technologies such as evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, moving networks, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation are being developed in 5G communication systems.In addition, advanced coding modulation (ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), as well as advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (non-orthogonal multiple access), and SCMA (sparse code multiple access) are being developed in 5G systems.

[0034] Meanwhile, the Internet is evolving from a human-centric network where humans create and consume information to an Internet of Things (IoT) network where information is exchanged and processed between distributed components, such as objects. The Internet of Everything (IoE) is also emerging, combining IoT technologies with big data processing technologies, such as those connected to cloud servers. To implement the IoT, technological elements such as sensing technology, wireless and wired communication and network infrastructure, service interface technology, and security technology are required. Recently, research is being conducted on technologies such as sensor networks, Machine-to-Machine (M2M), and Machine-Type Communication (MTC) for connecting objects. In the IoT environment, intelligent IT (Internet Technology) services can be provided that collect and analyze data generated from connected objects to create new value for human life. IoT can be applied to areas such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services through the convergence and integration of existing IT (information technology) technologies with various industries.

[0035] Accordingly, various attempts are being made to apply 5G communication systems (also known as New Radio (NR)) to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) are being implemented using 5G communication techniques such as beamforming, MIMO, and array antennas. The application of cloud RAN, a big data processing technology described above, can also be considered an example of the convergence of 3eG and IoT technologies.

[0036] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] Hereinafter, the base station is an entity that performs resource allocation of a 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, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although LTE (Long-Term Evolution), LTE-A (LTE-Advanced) or a 5G system may be described below as an example, 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 the fifth-generation mobile communication technology (5G, new radio, NR) developed after LTE-A. The term "5G" below may also encompass existing LTE, LTE-A, and other similar services. Furthermore, the present disclosure may be applied to other communication systems with some modifications, as determined by a person with skilled technical knowledge, without significantly departing from the scope of the present disclosure.

[0041] 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).

[0042] 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.

[0043] 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'. In addition, the components and '~parts' may be implemented to play one or more central processing units (CPUs) within the device or secure multimedia card. Also, in an embodiment, the '~part' may include one or more processors.

[0044] 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.

[0045] As a representative example of the above broadband wireless communication system, the LTE system adopts the Orthogonal Frequency Division Multiplexing (OFDM) method in the downlink (DL) and the Single Carrier Frequency Division Multiple Access (SC-FDMA) 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, gNode 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.

[0046] 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).

[0047] 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.

[0048] 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 / km^2) 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 not covered by cells, such as basements, and thus may require wider coverage than 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.

[0049] Finally, URLLC refers to cellular-based wireless communication services used for specific mission-critical purposes. Examples include remote control of robots or machinery, industrial automation, unmanned aerial vehicles (UAVs), remote health care, and emergency alerts. Therefore, URLLC communications must offer extremely low latency and high reliability. For example, URLLC-enabled services must meet air interface latency requirements of less than 0.5 milliseconds and a packet error rate (PER) of less than 10^-5. Therefore, for services supporting URLLC, 5G systems must provide shorter transmission time intervals (TTIs) than other services, and design considerations may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0050] 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.

[0051] [NR time-frequency resources]

[0052] Below, the frame structure of the 5G system is described in more detail with reference to drawings.

[0053] 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.

[0054] 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 (Orthogonal Frequency Division Multiplexing) symbol (102) on the time axis and 1 subcarrier (103) on the frequency axis. In the frequency domain (For example, 12) consecutive REs can form one resource block (RB, 104).

[0055] 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.

[0056] Figure 2 illustrates an example of a structure of a frame (Frame, 200), a subframe (Subframe, 201), and a slot (Slot, 202). One frame (200) can be defined as 10 ms. One subframe (201) can be defined as 1 ms, 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, the 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 1 slot (202), and when μ = 1 (205), 1 subframe (201) may be composed of 2 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 shown in Table 1 below.

[0057]

[0058] [Bandwidth Part (BWP)]

[0059] Next, the bandwidth part (BWP) setting in the 5G communication system will be explained in detail with reference to the drawing.

[0060] 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.

[0061] Figure 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.

[0062]

[0063] 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 (Downlink Control Information).

[0064] According to some embodiments, a terminal before RRC (Radio Resource Control) connection can receive configuration information for 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 for a control region (Control Resource Set, CORESET) and a search space, through the MIB, in the initial access phase, where a PDCCH for receiving system information required for initial access (which may correspond to Remaining System Information (RMSI) or System Information Block 1 (SIB1)) can be transmitted. The control region and search space configured by the MIB may 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 region #0 through the MIB. In addition, the base station can notify the terminal of configuration information for a monitoring cycle and occasion for control region #0, i.e., configuration information for search space #0, through the MIB. The terminal may consider the frequency range set as control area #0 obtained from the MIB as the initial bandwidth portion for initial connection. At this time, the identifier (ID) of the initial bandwidth portion may be considered as 0.

[0065] The bandwidth settings supported by 5G systems can be used for various purposes.

[0066] In one embodiment, 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.

[0067] 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 15 kHz and 30 kHz subcarrier spacing for a given terminal, the base station may configure two bandwidth segments with subcarrier spacings of 15 kHz and 30 kHz, respectively. The different bandwidth segments may be frequency-division multiplexed, and when data is to be transmitted and received using a specific subcarrier spacing, the bandwidth segment configured for that subcarrier spacing may be activated.

[0068] Furthermore, according to one embodiment, for the purpose of reducing power consumption of the terminal, the base station can set bandwidth portions with different bandwidth sizes for 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 situation can be very inefficient in terms of power consumption. To reduce power consumption of the terminal, the base station can set a bandwidth portion with a relatively small bandwidth, such as 20 MHz, for the terminal. In a traffic-free situation, the terminal can perform monitoring operations in the 20 MHz bandwidth portion, and when data is generated, it can transmit and receive data using the 100 MHz bandwidth portion according to the instructions of the base station.

[0069] In the method of configuring the bandwidth part, terminals before RRC connection (Connected) can receive configuration information for the initial bandwidth part through the MIB (Master Information Block) during the initial access stage. More specifically, the terminal can receive a control region (Control Resource Set, CORESET) for a downlink control channel on which downlink control information (DCI) that schedules a system information block (SIB) can be transmitted from the MIB of the physical broadcast channel (PBCH). The bandwidth of the control region configured by the MIB can be regarded as the initial bandwidth part, and the terminal can receive the physical downlink shared channel (PDSCH) on which the SIB is transmitted through the configured initial bandwidth part. In addition to receiving the SIB, the initial bandwidth part can also be utilized for other system information (Other System Information, OSI), paging, and random access.

[0070] [Bandwidth Part (BWP) Change]

[0071] When one or more bandwidth parts are set for a terminal, the base station can instruct the terminal to change (or switch, transition) the bandwidth part 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.

[0072] As mentioned above, since DCI-based bandwidth part changes can be indicated by the DCI scheduling the PDSCH or PUSCH, when a UE receives a bandwidth part change request, it must be able to seamlessly receive or transmit the PDSCH or PUSCH scheduled by the corresponding DCI in the changed bandwidth part. To this end, the standard stipulates requirements for the delay time (TBWP) required when changing the bandwidth part, which can be defined, for example, as shown in Table 3.

[0073]

[0074] 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.

[0075] 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. BWP It 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.

[0076] 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 from the third symbol of the slot in which the PDCCH including the DCI is received 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).

[0077] [SS / PBCH block]

[0078] Next, we will explain the SS (Synchronization Signal) / PBCH block in the 5G system.

[0079] An SS / PBCH block may refer to a physical layer channel block consisting of a PSS (Primary SS), SSS (Secondary SS), and PBCH. Specifically, it is as follows.

[0080] - PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides some information about the cell ID.

[0081] - SSS: It serves as a reference for downlink time / frequency synchronization and provides the remaining cell ID information not provided by PSS. Additionally, it can serve as a reference signal for PBCH demodulation.

[0082] - PBCH: Provides essential system information required for the terminal's data channel and control channel transmission and reception. Essential system information may include search space-related control information indicating radio resource mapping information for the control channel, and scheduling control information for a separate data channel that transmits system information.

[0083] - SS / PBCH Block: An SS / PBCH block is composed of a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks can be transmitted within a 5ms period, and each transmitted SS / PBCH block can be distinguished by an index.

[0084] The terminal can detect PSS and SSS in the initial access stage, and decode PBCH. The terminal can obtain MIB from PBCH, and can set control region (Control Resource Set; CORESET) #0 (which may correspond to a control region with a control region index of 0) therefrom. The terminal can monitor control region #0, assuming that the selected SS / PBCH block and the DMRS (Demodulation Reference Signal) transmitted in control region #0 are QCL (Quasi Co Location). The terminal can receive system information through downlink control information transmitted in control region #0. The terminal can obtain RACH (Random Access Channel) related configuration information required for initial access from the received system information. The terminal can transmit PRACH (Physical RACH) to the base station considering the selected SS / PBCH index, and the base station receiving the PRACH can obtain information on the SS / PBCH block index selected by the terminal. The base station can know that the terminal has selected a block among each SS / PBCH block and monitors the control region #0 associated with it.

[0085] [PDCCH: DCI related]

[0086] Next, we will specifically explain downlink control information (DCI) in the 5G system.

[0087] 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.

[0088] 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.

[0089] 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).

[0090] 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.

[0091]

[0092] 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.

[0093]

[0094]

[0095] 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.

[0096]

[0097] 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.

[0098]

[0099] [PDCCH: CORESET, REG, CCE, Search Space]

[0100] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0101] FIG. 4 is a diagram illustrating an example of setting a control region of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure. FIG. 4 illustrates an example of a control region (Control Resource Set, CORESET) in which a downlink control channel is transmitted in a 5G wireless communication system. FIG. 4 illustrates an example in which two control regions (Control Region #1 (401), Control Region #2 (402)) are set within a UE bandwidth part (410) in the frequency axis and one slot (420) in the time axis. The control regions (401, 402) may be set to specific frequency resources (403) within the entire UE bandwidth part (410) in the frequency axis. The control regions (401, 402) may be set to one or more OFDM symbols in the time axis, and this may be defined as a control region length (Control Resource Set Duration, 404). Referring to the illustrated example of FIG. 4, control area #1 (401) is set to a control area length of 2 symbols, and control area #2 (402) is set to a control area length of 1 symbol.

[0102] In the aforementioned 5G system, the control region can be established by the base station to the terminal through higher-layer signaling (e.g., system information, Master Information Block (MIB), Radio Resource Control (RRC) signaling). The base station establishing a control region for the terminal means that the base station provides the terminal with information such as the control region identifier (Identity), 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.

[0103]

[0104] 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.

[0105] FIG. 5 is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0106] Fig. 5 shows an example of a basic unit of time and frequency resources that constitute a downlink control channel that can be used in a 5G system. According to Fig. 5, the basic unit of time and frequency resources that constitute a control channel can be referred to as a REG (Resource Element Group, 503), and a REG (503) can be defined as 1 OFDM symbol (501) on the time axis and 1 PRB (Physical Resource Block, 502) on the frequency axis, i.e., 12 subcarriers. A base station can concatenate REGs (503) to constitute a downlink control channel allocation unit.

[0107] As illustrated in FIG. 5, if the basic unit to which a downlink control channel is allocated in a 5G system is called a CCE (Control Channel Element, 504), 1 CCE (504) can be composed of multiple REGs (503). Taking the REG (503) illustrated in FIG. 5 as an example, the REG (503) can be composed of 12 REs, and if 1 CCE (504) is composed of 6 REGs (503), 1 CCE (504) can be composed of 72 REs. When a downlink control region is set, the region can be composed of multiple CCEs (504), and a specific downlink control channel can be mapped to one or multiple CCEs (504) and transmitted according to the aggregation level (AL) within the control region. CCEs (504) within the control area are distinguished by numbers, and the numbers of the CCEs (504) can be assigned according to a logical mapping method.

[0108] The basic unit of the downlink control channel illustrated in FIG. 5, that is, the REG (503), may include both the REs to which the DCI is mapped and the areas to which the DMRS (505), which is a reference signal for decoding the REs, is mapped. As shown in FIG. 5, three DMRSs (505) may be transmitted within one REG (503). 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.

[0109] 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.

[0110] In a 5G system, parameters for a search space for PDCCH can be configured from a base station to a 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 parameters for a search space for PDCCH can include the information in Table 9.

[0111]

[0112] 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.

[0113] 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.

[0114] 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.

[0115] - 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

[0116] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0117] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0118] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0119] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0120] In a terminal-specific search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these examples.

[0121] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0122] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0123] The RNTIs specified may follow the definitions and uses below.

[0124] C-RNTI (Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0125] TC-RNTI (Temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0126] CS-RNTI (Configured Scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0127] RA-RNTI (Random Access RNTI): Used for PDSCH scheduling in the random access phase.

[0128] P-RNTI (Paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0129] SI-RNTI (System Information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0130] INT-RNTI (Interruption RNTI): Used to indicate whether pucturing is in progress for PDSCH.

[0131] TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to indicate power control commands for PUSCH.

[0132] TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to indicate power control commands for PUCCH.

[0133] TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used to indicate power control commands for SRS.

[0134] The aforementioned specified DCI formats may follow definitions such as the examples in Table 10.

[0135]

[0136] In a 5G system, the search space of aggregation level L in a control region p and a search space set s can be expressed as in the following mathematical expression 1.

[0137]

[0138] - : Integration level

[0139] - Carrier Index

[0140] - Total number of CCEs existing within the control region p

[0141] - Slot Index

[0142] - Number of PDCCH candidates for aggregation level L

[0143] - PDCCH candidate index for aggregation level L

[0144] -

[0145] -

[0146] - : Terminal identifier

[0147] The value can be 0 for a common search space.

[0148] 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.

[0149] In a 5G system, since multiple search space sets can be set 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 set with an X-slot period and search space set #2 is set 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.

[0150] [PDCCH: BD / CCE limit]

[0151] When multiple search space sets are set for a terminal, the following conditions may be considered in determining the search space set that the terminal should monitor.

[0152] If the value of monitoringCapabilityConfig-r16, which is an upper layer signaling, is set to r15monitoringcapability, the terminal defines the maximum values ​​for the number of PDCCH candidates that can be monitored and the number of CCEs that constitute the entire search space (wherein the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) per slot, and if the value of monitoringCapabilityConfig-r16 is set to r16monitoringcapability, the terminal defines the maximum values ​​for the number of PDCCH candidates that can be monitored and the number of CCEs that constitute the entire search space (wherein the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) per Span.

[0153] [Condition 1: Limit the maximum number of PDCCH candidates]

[0154] As described above, depending on the setting value of the upper layer signaling, the maximum number of PDCCH candidates that the terminal can monitor is M. μ is a subcarrier spacing of 15·2 μ When defined by slot in a cell set to kHz, Table 11 below can be followed, and when defined by span, Table 12 below can be followed.

[0155]

[0156]

[0157] [Condition 2: Maximum CCE limit]

[0158] As above, according to the setting value of the upper layer signaling, the maximum number of CCEs that constitute the entire search space (here, the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) is C μ is a subcarrier spacing of 15·2 μWhen defined by slot in a cell set to kHz, Table 13 below may be followed, and when defined by span, Table 14 below may be followed.

[0159]

[0160]

[0161] For convenience of explanation, let us define a situation where both conditions 1 and 2 are satisfied at a certain point in time as “condition A.” Therefore, not satisfying condition A may mean not satisfying at least one of conditions 1 and 2.

[0162] [PDCCH: Overbooking]

[0163] Depending on the configuration of the search space sets of the base station, there may be cases where condition A is not satisfied at a certain point in time. If condition A is not satisfied at a certain point in time, the terminal can select and monitor only some of the search space sets configured to satisfy condition A at that point in time, and the base station can transmit a PDCCH to the selected search space set.

[0164] The following method can be followed to select a partial search space from the entire set of search spaces.

[0165] If condition A for PDCCH is not satisfied at a specific point in time (slot), the terminal (or base station) may preferentially select a search space set whose search space type is set to a common search space from among the search space sets existing at that point in time over a search space set whose search space type is set to a terminal-specific search space.

[0166] If all search space sets set as common search spaces are selected (i.e., if condition A is satisfied even after selecting all search spaces set as common search spaces), the terminal (or base station) can select search space sets set as terminal-specific search spaces. At this time, if there are multiple search space sets set as terminal-specific search spaces, a search space set with a lower search space set index may have a higher priority. The terminal (or base station) can select terminal-specific search space sets within the range where condition A is satisfied, taking the priority into consideration.

[0167] [Rate matching / Puncturing related]

[0168] Below, the rate matching operation and puncturing operation are described in detail.

[0169] When a time and frequency resource A, through which an arbitrary symbol sequence A is to be transmitted, overlaps with an arbitrary time and frequency resource B, a rate matching or puncturing operation may be considered for transmission and reception operations of channel A considering resource C, an area in which resources A and B overlap. The specific operations may follow the contents below.

[0170] Rate Matching Operation

[0171] - The base station can map and transmit channel A only for the remaining resource areas excluding resource C corresponding to the overlapping area with resource B among the entire resources A that want to transmit symbol sequence A to the terminal. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the base station can sequentially map and transmit symbol sequence A to {resource #1, resource #2, resource #4}, which are the remaining resources among resource A excluding {resource #3} corresponding to resource C. As a result, the base station can map and transmit symbol sequences {symbol #1, symbol #2, symbol #3} to {resource #1, resource #2, resource #4}, respectively.

[0172] The terminal can determine resources A and B from scheduling information for symbol sequence A from the base station, and can thereby determine resource C, which is an area where resources A and B overlap. The terminal can receive symbol sequence A, assuming that symbol sequence A was mapped and transmitted in the remaining area of ​​the entire resource A except for resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, and resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the terminal can receive symbol sequence A, assuming that it was sequentially mapped to {resource #1, resource #2, resource #4}, which are the remaining resources of resource A except {resource #3}, which corresponds to resource C. As a result, the terminal can perform a series of subsequent reception operations, assuming that symbol sequences {symbol #1, symbol #2, symbol #3} were mapped and transmitted to {resource #1, resource #2, resource #4}, respectively.

[0173] Puncture action

[0174] If a base station wants to transmit symbol sequence A to a terminal, and there is a resource C corresponding to an area overlapping with resource B among all resources A, the base station maps symbol sequence A to the entire resource A, but does not perform transmission in the resource area corresponding to resource C, and can perform transmission only for the remaining resource areas of resource A excluding resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the base station can map symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} to resource A {resource #1, resource #2, resource #3, resource #4}, and transmit only the symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to the remaining resources {resource #1, resource #2, resource #4} excluding {resource #3} corresponding to resource C among resources A, and may not transmit {symbol #3} mapped to {resource #3} corresponding to resource C. As a result, the base station can transmit symbol sequences {symbol #1, symbol #2, symbol #4} by mapping them to {resource #1, resource #2, resource #4}, respectively.

[0175] The terminal can determine resources A and B from scheduling information for symbol sequence A from the base station, and can thereby determine resource C, which is an area where resources A and B overlap. The terminal can receive symbol sequence A assuming that symbol sequence A is mapped to the entire resource A, but is transmitted only in the remaining area of ​​resource area A excluding resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the terminal can assume that symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} is mapped to resource A {resource #1, resource #2, resource #3, resource #4} respectively, but {symbol #3} mapped to {resource #3} corresponding to resource C is not transmitted, and can receive it assuming that symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to {resource #1, resource #2, resource #4}, which are the remaining resources among resource A except {resource #3} corresponding to resource C, are mapped and transmitted. As a result, the terminal can assume that the symbol sequence {symbol #1, symbol #2, symbol #4} is transmitted by being mapped to {resource #1, resource #2, resource #4}, respectively, and perform a series of subsequent receiving operations.

[0176] Below, we describe a method for configuring rate-matching resources for the purpose of rate-matching in 5G communication systems. Rate-matching refers to adjusting the size of a signal based on the amount of resources available for transmission. For example, rate-matching a data channel may mean adjusting the size of data accordingly, without mapping the data channel to a specific time and frequency resource region.

[0177] FIG. 6 is a diagram for explaining a method for a base station and a terminal to transmit and receive data by taking into account downlink data channels and rate matching resources according to one embodiment of the present disclosure.

[0178] FIG. 6 illustrates a downlink data channel (PDSCH, 601) and a rate matching resource (602). A base station can configure one or more rate matching resources (602) to a terminal through upper layer signaling (e.g., RRC signaling). Rate matching resource (602) configuration information may include time-domain resource allocation information (603), frequency-domain resource allocation information (604), and period information (605). In the following, the bitmap corresponding to the frequency-domain resource allocation information (604) is named “first bitmap,” the bitmap corresponding to the time-domain resource allocation information (603) is named “second bitmap,” and the bitmap corresponding to the period information (605) is named “third bitmap.” If all or part of the time and frequency resources of the scheduled data channel (601) overlap with the set rate matching resources (602), the base station can rate-match and transmit the data channel (601) in the rate matching resource (602) portion, and the terminal can perform reception and decoding after assuming that the data channel (601) is rate-matched in the rate matching resource (602) portion.

[0179] The base station can dynamically notify the terminal via DCI whether to rate-match the data channel in the set rate-matching resource portion through additional configuration (corresponding to the “rate-matching indicator” in the aforementioned DCI format). Specifically, the base station can select some of the set rate-matching resources and group them into rate-matching resource groups, and can use a bitmap to indicate to the terminal via DCI whether the data channel for each rate-matching resource group is rate-matched. For example, if four rate-matching resources, RMR#1, RMR#2, RMR#3, and RMR#4, are set, the base station can set RMG#1={RMR#1, RMR#2}, RMG#2={RMR#3, RMR#4} as the rate-matching groups, and can use two bits in the DCI field to indicate to the terminal whether to rate-match in RMG#1 and RMG#2, respectively, using a bitmap. For example, if rate matching is required, it can be indicated as “1”, and if rate matching is not required, it can be indicated as “0”.

[0180] In 5G systems, granularity at the "RB symbol level" and "RE level" is supported by setting the aforementioned rate matching resources on terminals. More specifically, the following configuration method can be followed.

[0181] RB symbol level

[0182] A terminal can receive up to four RateMatchPatterns for each bandwidth section through upper layer signaling, and one RateMatchPattern can include the following contents.

[0183] - As a reserved resource within the bandwidth section, a resource in which the time and frequency resource domains of the reserved resource are set by combining a bitmap at the RB level and a bitmap at the symbol level along the frequency axis may be included. The reserved resource may span one or two slots. A time domain pattern (periodicityAndPattern) in which the time and frequency domains composed of each RB level and symbol level bitmap pair are repeated may additionally be set.

[0184] - It may include a time and frequency domain resource area set as a control resource set within the bandwidth section and a resource area corresponding to a time domain pattern set as a search space setting in which the resource area is repeated.

[0185] RE level

[0186] The terminal can be configured with the following contents through upper layer signaling.

[0187] - The configuration information (lte-CRS-ToMatchAround) for RE corresponding to the LTE CRS (Cell-specific Reference Signal or Common Reference Signal) pattern may include the number of LTE CRS ports (nrofCRS-Ports) and the LTE-CRS-vshift(s) value (v-shift), the location information (carrierFreqDL) of the center subcarrier of the LTE carrier from the reference frequency point (e.g., reference point A), the bandwidth size (carrierBandwidthDL) information of the LTE carrier, and the subframe configuration information (mbsfn-SubframConfigList) corresponding to the MBSFN (Multicast-broadcast single-frequency network). Based on the above-described information, the terminal can determine the location of the CRS within the NR slot corresponding to the LTE subframe.

[0188] - It may include configuration information for a set of resources corresponding to one or more ZP (Zero Power) CSI-RSs within the bandwidth section.

[0189] [Regarding LTE CRS rate match]

[0190] Next, the rate match process for the LTE CRS described above will be described in detail. In order to coexist between LTE (Long Term Evolution) and NR (New RAT) (LTE-NR Coexistence), NR provides a function to set a pattern of LTE's CRS (Cell Specific Reference Signal) to NR terminals. More specifically, the CRS pattern can be provided by RRC signaling including at least one parameter in the ServingCellConfig IE (Information Element) or ServingCellConfigCommon IE. Examples of the parameters can include lte-CRS-ToMatchAround, lte-CRS-PatternList1-r16, lte-CRS-PatternList2-r16, crs-RateMatch-PerCORESETPoolIndex-r16, etc.

[0191] In Rel-15 NR, the lte-CRS-ToMatchAround parameter provides a function that allows one CRS pattern to be set per serving cell. In Rel-16 NR, the function has been extended to allow multiple CRS patterns to be set per serving cell. More specifically, a single-TRP (transmission and reception point) configured terminal can have one CRS pattern set per LTE carrier, and a multi-TRP configured terminal can have two CRS patterns set per LTE carrier. For example, a single-TRP configured terminal can have up to three CRS patterns set per serving cell through the lte-CRS-PatternList1-r16 parameter. As another example, a multi-TRP configured terminal can have CRS set per TRP. That is, the CRS pattern for TRP1 can be set via the lte-CRS-PatternList1-r16 parameter, and the CRS pattern for TRP2 can be set via the lte-CRS-PatternList2-r16 parameter. Meanwhile, when two TRPs are set as above, whether both the CRS patterns of TRP1 and TRP2 or only the CRS pattern for one TRP is applied to a specific PDSCH (Physical Downlink Shared Channel) is determined via the crs-RateMatch-PerCORESETPoolIndex-r16 parameter. If the crs-RateMatch-PerCORESETPoolIndex-r16 parameter is set to enabled, only the CRS pattern of one TRP is applied, and in other cases, the CRS patterns of both TRPs are applied.

[0192] Table 15 shows a ServingCellConfig IE that includes the above CRS pattern, and Table 16 shows a RateMatchPatternLTE-CRS IE that includes at least one parameter for the CRS pattern.

[0193]

[0194]

[0195]

[0196] [PDSCH: Frequency Resource Allocation Related]

[0197] FIG. 7 is a diagram illustrating an example of frequency-axis resource allocation of PDSCH in a wireless communication system according to an embodiment of the present disclosure.

[0198] FIG. 7 is a diagram illustrating three frequency axis resource allocation methods, type 0 (700), type 1 (705), and dynamic switch (710), which can be set through an upper layer in an NR wireless communication system.

[0199] Referring to Fig. 7, if a terminal is set to use only resource type 0 through upper layer signaling (700), some downlink control information (DCI) that allocates PDSCH to the terminal includes a bitmap composed of NRBG bits. The conditions for this will be explained later. At this time, NRBG means the number of RBGs (resource block groups) determined according to the BWP size allocated by the BWP indicator and the upper layer parameter rbg-Size as shown in [Table 17] below, and data is transmitted to the RBG indicated as 1 by the bitmap.

[0200]

[0201] If the terminal is configured to use only resource type 1 through upper layer signaling (705), some DCIs that allocate PDSCH to the terminal It includes frequency axis resource allocation information consisting of bits. The conditions for this will be explained later. Through this, the base station can set the starting VRB (720) and the length (725) of frequency axis resources allocated continuously therefrom.

[0202] If a terminal is configured to use both resource type 0 and resource type 1 through upper layer signaling (710), some DCIs that allocate PDSCH to the terminal include frequency-axis resource allocation information composed of bits of a larger value (735) among the payload (715) for configuring resource type 0 and the payload (720, 725) for configuring resource type 1. Conditions for this will be explained later. At this time, one bit may be added to the first part (MSB) of the frequency-axis resource allocation information in the DCI, and if the bit has a value of '0', it may indicate that resource type 0 is used, and if the bit has a value of '1', it may indicate that resource type 1 is used.

[0203] [PDSCH / PUSCH: Time Resource Allocation Related]

[0204] Below, a time domain resource allocation method for data channels in next-generation mobile communication systems (5G or NR systems) is described.

[0205] A base station can set up a table for time domain resource allocation information for a downlink data channel (Physical Downlink Shared Channel, PDSCH) and an uplink data channel (Physical Uplink Shared Channel, PUSCH) to a terminal through higher layer signaling (e.g., RRC signaling). A table with up to maxNrofDL-Allocations=16 entries can be set up for PDSCH, and a table with up to maxNrofUL-Allocations=16 entries can be set up for PUSCH. In one embodiment, the time domain resource allocation information may include PDCCH-to-PDSCH slot timing (corresponding to the time interval in slot units between the time point at which a PDCCH is received and the time point at which a PDSCH scheduled by the received PDCCH is transmitted, denoted as K0), PDCCH-to-PUSCH slot timing (corresponding to the time interval in slot units between the time point at which a PDCCH is received and the time point at which a PUSCH scheduled by the received PDCCH is transmitted, denoted as K2), information on the position and length of the start symbol for which a PDSCH or PUSCH is scheduled within a slot, the mapping type of the PDSCH or PUSCH, etc. For example, information such as [Table 18] or [Table 19] below may be transmitted from the base station to the terminal.

[0206]

[0207]

[0208] The base station can notify the terminal of one of the entries in the table for the time domain resource allocation information described above via L1 signaling (e.g., DCI). For example, this may be indicated by the "Time Domain Resource Allocation" field in the DCI. The terminal can obtain time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

[0209] FIG. 8 is a diagram illustrating an example of time axis resource allocation of PDSCH in a wireless communication system according to one embodiment of the present disclosure.

[0210] Referring to FIG. 8, the base station uses the upper layer to set the subcarrier spacing (SCS) (μ) of the data channel and the control channel. PDSCH , μ PDCCH ), scheduling offset (K0) value, and the time axis position of the PDSCH resource can be indicated according to the OFDM symbol start position (800) and length (805) within a slot dynamically indicated through DCI.

[0211] FIG. 9 is a diagram illustrating an example of time-domain resource allocation according to subcarrier spacing of a data channel and a control channel in a wireless communication system according to one embodiment of the present disclosure.

[0212] Referring to Fig. 9, when the subcarrier spacing of the data channel and the control channel is the same (900, μ PDSCH = μ PDCCH), since the slot numbers for data and control are the same, the base station and the terminal can generate a scheduling offset according to the predetermined slot offset K0. On the other hand, if the subcarrier spacing of the data channel and the control channel are different (905, μ PDSCH ≠ μ PDCCH ), since the slot numbers for data and control are different, the base station and the terminal can generate a scheduling offset according to a predetermined slot offset K0 based on the subcarrier interval of the PDCCH.

[0213] [PUSCH: Transmission method related]

[0214] 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.

[0215] Configured grant Type 1 PUSCH transmission can be semi-statically configured by receiving configuredGrantConfig including rrc-ConfiguredUplinkGrant of [Table 20] through higher-order 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 20] through higher-order signaling. When PUSCH transmission operates by configured grant, parameters applied to PUSCH transmission are applied through configuredGrantConfig of higher-order signaling of [Table 20], except for dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and scaling of UCI-OnPUSCH provided by pusch-Config of [Table 21]. If the terminal has been provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 20], the terminal applies tp-pi2BPSK in pusch-Config of [Table 21] to PUSCH transmission operated by the configured grant.

[0216]

[0217]

[0218] 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 21], is 'codebook' or 'nonCodebook'.

[0219] 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 21], the UE does not expect to be scheduled with DCI format 0_1.

[0220]

[0221] 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).

[0222] 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.

[0223] 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'.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] 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.

[0229] If a periodic or semi-persistent SRS resource set is configured, the associated NZP CSI-RS can be indicated through the associatedCSI-RS in 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 in the upper-level signaling SRS-ResourceSet to be configured together.

[0230] 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.

[0231] 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.

[0232] [PUSCH: Preparation time]

[0233] Next, the PUSCH preparation procedure time is described. When the base station schedules a UE to transmit a PUSCH using DCI format 0_0, 0_1, or 0_2, the UE may require a PUSCH preparation procedure time to transmit the PUSCH by applying the transmission method indicated through the DCI (transmission precoding method of SRS resources, number of transmission layers, spatial domain transmission filter). NR takes this into account and defines the PUSCH preparation procedure time. The PUSCH preparation procedure time of the UE can follow the following [Mathematical Formula 2].

[0234]

[0235] T as described in mathematical formula 2 proc,2 In , each variable can have the following meanings:

[0236] - N2: The number of symbols determined by the UE processing capability (UE processing capability) 1 or 2 and the numerology μ according to the UE capability. If UE processing capability 1 is reported according to the UE capability report, it has the value of [Table 22]. If UE processing capability 2 is reported and the availability of UE processing capability 2 is set through upper layer signaling, it can have the value of [Table 23].

[0237]

[0238]

[0239] - d 2,1 : The number of symbols set to 0 if all resource elements of the first OFDM symbol of PUSCH transmission are configured to consist of only DM-RS, and 1 otherwise.

[0240] - : 64

[0241] - μ: μ DL or μ UL Medium, T proc,2 This follows the larger value μ DL refers to the numerology of the downlink in which the PDCCH containing the DCI scheduling the PUSCH is transmitted, and μ UL It refers to the numerology of the uplink in which PUSCH is transmitted.

[0242] - T c : 1 / ( f max *N f ), f max = 480*10 3 Hz, N f =has 4096.

[0243] - d 2,2 : If the DCI scheduling the PUSCH indicates BWP switching, it follows the BWP switching time, otherwise it has 0.

[0244] - d2: When the OFDM symbols of a PUCCH with a high priority index and a PUCCH with a low priority index overlap in time, the d2 value of the PUSCH with the high priority index is used. Otherwise, d2 is 0.

[0245] - T ext : If the terminal uses a shared spectrum channel access method, the terminal is T ext can be calculated and applied to the PUSCH preparation process time. Otherwise, T ext is assumed to be 0.

[0246] - T switch : T when the uplink switching interval is triggered switch is assumed to be the switching interval time. Otherwise, it is assumed to be 0.

[0247] When the base station and the terminal consider the time domain resource mapping information of the PUSCH scheduled through DCI and the influence of the timing advance between uplink and downlink, the base station and the terminal determine T from the last symbol of the PDCCH including the DCI that scheduled the PUSCH. proc,2 If the first symbol of the PUSCH begins before the first uplink symbol of the CP, the PUSCH preparation time is determined to be insufficient. Otherwise, the base station and the UE determine that the PUSCH preparation time is sufficient. The UE transmits the PUSCH only when the PUSCH preparation time is sufficient, and may ignore the DCI scheduling the PUSCH if the PUSCH preparation time is insufficient.

[0248] [CA / DC related]

[0249] FIG. 10 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, or dual connectivity situation according to one embodiment of the present disclosure.

[0250] Referring to FIG. 10, the wireless protocol of the next-generation mobile communication system is composed of NR SDAP (Service Data Adaptation Protocol 1025, 1070), NR PDCP (Packet Data Convergence Protocol 1030, 1065), NR RLC (Radio Link Control 1035, 1060), and NR MAC (Medium Access Control 1040, 1055) in the terminal and NR base station, respectively.

[0251] The main functions of NR SDAP (1025, 1070) may include some of the following functions:

[0252] - Transfer of user plane data

[0253] - Mapping function between QoS flow and data bearer for both DL and UL

[0254] - Marking function of QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0255] - Ability to map reflective QoS flow to data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0256] For the above SDAP layer device, the terminal can be configured by 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.

[0257] The main functions of NR PDCP (1030, 1065) may include some of the following functions:

[0258] - Header compression and decompression (ROHC only)

[0259] - User data transfer function

[0260] - In-sequence delivery of upper layer PDUs

[0261] - Out-of-sequence delivery of upper layer PDUs

[0262] - PDCP PDU reordering for reception

[0263] - Duplicate detection of lower layer SDUs

[0264] - Retransmission function (Retransmission of PDCP SDUs)

[0265] - Encryption and decryption functions (Ciphering and deciphering)

[0266] - Timer-based SDU discard in uplink.

[0267] 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.

[0268] The main functions of NR RLC (1035, 1060) may include some of the following functions:

[0269] - Data transfer function (Transfer of upper layer PDUs)

[0270] - In-sequence delivery of upper layer PDUs

[0271] - Out-of-sequence delivery of upper layer PDUs

[0272] - ARQ function (Error Correction through ARQ)

[0273] - Concatenation, segmentation and reassembly of RLC SDUs

[0274] - Re-segmentation of RLC data PDUs

[0275] - Reordering of RLC data PDUs

[0276] - Duplicate detection function

[0277] - Protocol error detection

[0278] - RLC SDU discard function

[0279] - RLC re-establishment function

[0280] 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.

[0281] 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 an original RLC SDU is received divided into multiple RLC SDUs, and may include a function of storing the RLC SN or PDCP SN of received RLC PDUs and arranging the order to record lost RLC PDUs.

[0282] NR MAC (1040, 1055) 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.

[0283] - Mapping function (Mapping between logical channels and transport channels)

[0284] - Multiplexing / demultiplexing of MAC SDUs

[0285] - Scheduling information reporting function

[0286] - HARQ function (Error correction through HARQ)

[0287] - Priority handling between logical channels of one UE

[0288] - Priority handling between UEs by means of dynamic scheduling

[0289] - MBMS service identification function

[0290] - Transport format selection function

[0291] - Padding function

[0292] The NR PHY layer (1045, 1050) 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.

[0293] 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 1000. On the other hand, when a base station transmits data to a terminal based on CA (carrier aggregation) that uses multiple carriers in a single TRP, the base station and the terminal use a protocol structure that has a single structure up to RLC, such as 1010, but multiplexes the PHY layer through the MAC layer. As another example, when a base station transmits data to a terminal based on DC (dual connectivity) that uses multiple carriers in multiple TRPs, the base station and the terminal use a protocol structure that has a single structure up to RLC, such as 1020, but multiplexes the PHY layer through the MAC layer.

[0294] Referring to the above-described PDCCH and beam configuration-related descriptions, the current Rel-15 and Rel-16 NR do not support repeated PDCCH transmission, making it difficult to achieve the required reliability in scenarios requiring high reliability, such as URLLC. The present invention provides a method for repeated PDCCH transmission through multiple transmission points (TRPs) to improve the reliability of PDCCH reception by a terminal. The specific method is described in detail in the following examples.

[0295] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. The contents of the present disclosure can be applied to FDD and TDD systems. 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 MAC (medium access control) control element (MAC control element; MAC CE).

[0296] 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.

[0297] 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.

[0298] 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.

[0299] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. Hereinafter, a base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, a gNB, 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. Although the embodiments of the present disclosure are described below using a 5G system as an example, the embodiments of the present disclosure may 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. Therefore, the embodiments of the present disclosure may be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure as determined by a person skilled in the art. The contents of the present disclosure can be applied to FDD and TDD systems.

[0300] Additionally, when describing the present disclosure, detailed descriptions of related functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present disclosure. Furthermore, the terms described below are defined based on the functions of the present disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the contents of this specification.

[0301] 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.

[0302] - MIB (Master Information Block)

[0303] - SIB (System Information Block) or SIB

[0304] - RRC (Radio Resource Control)

[0305] - MAC (Medium Access Control) CE (Control Element)

[0306] 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.

[0307] - PDCCH (Physical Downlink Control Channel)

[0308] - DCI (Downlink Control Information)

[0309] - UE-specific DCI

[0310] - Group common DCI

[0311] - Common DCI

[0312] - Scheduling DCI (e.g. DCI used for scheduling downlink or uplink data)

[0313] - Non-scheduled DCI (e.g. DCI not intended for scheduling downlink or uplink data)

[0314] - PUCCH (Physical Uplink Control Channel)

[0315] - UCI (Uplink Control Information)

[0316] 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.

[0317] 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.

[0318] [Type-1 HARQ-ACK Codebook Related]

[0319] This section describes how to configure a Type-1 HARQ-ACK codebook in an NR system. Note that a Type-1 HARQ-ACK codebook is also called a semi-static HARQ-ACK codebook.

[0320] The following description assumes that a terminal is limited to one PUCCH on which HARQ-ACK information can be transmitted within a single time unit (e.g., slot, sub-slot, or mini-slot). Unless otherwise specified, the time unit is described as a slot, but this can be expanded to include sub-slots, mini-slots, etc.

[0321] A terminal may receive a semi-static HARQ-ACK codebook configuration from a base station. Here, the configuration may be set as a higher layer signal (e.g., an RRC signal). The terminal may receive a DCI format from the base station. The terminal may transmit HARQ-ACK information of a PDSCH, an SPS PDSCH release, or a Scell ​​dormancy indication scheduled by the DCI format in a slot indicated by a value of a PDSCH-to-HARQ_feedback timing indicator field in the DCI format. If the terminal is instructed to transmit multiple HARQ-ACK information in one slot, the terminal may generate the HARQ-ACK information into a HARQ-ACK codebook according to a predetermined rule and transmit it in one PUCCH in the slot.

[0322] The rules for generating a more specific semi-static HARQ-ACK codebook are as follows.

[0323] The terminal reports the HARQ-ACK information bit value in the HARQ-ACK codebook as NACK in slots not indicated by the PDSCH-to-HARQ_feedback timing indicator field in the DCI format.

[0324] If the terminal receives all M for candidate PDSCH reception A,C In cases where only HARQ-ACK information for one SPS PDSCH release or one PDSCH reception is reported, and the report is scheduled by DCI format 1_0 including information that the counter DACI field in the Pcell indicates 1, the UE determines one HARQ-ACK codebook for the corresponding SPS PDSCH release or the corresponding PDSCH reception.

[0325] Other than that, the HARQ-ACK codebook determination method is followed according to the method described below.

[0326] For the convenience of this disclosure, the PDSCH-to-HARQ_feedback timing indicator value is referred to as the K1 value. A terminal may be configured with multiple K1 values, and these multiple K1 values ​​are collectively referred to as a K1 set.

[0327] The set of PDSCH reception candidate opportunities (occasions) in serving cell c is M A,c , and after that M A,c Describes how to obtain or calculate .

[0328] First, let us assume that the PDSCH scheduled by the DCI format is received in a single slot. This may include cases where the pdsch-AggregationFactor is not set from the upper layer.

[0329] When transmitting a PUCCH or PUSCH carrying a Type-1 HARQ-ACK codebook in slot n, the pseudo-code for this is as follows.

[0330] [pseudo-code 1: (No PDSCH repeat reception)]

[0331] - Preparation phase: Set R is a set of scheduling information (slot information (hereinafter K0 value) to which PDSCH is mapped, starting symbol and length information (hereinafter SLIV (starting and length value)) set in the TDRA (time domain resource assignment) table. If the terminal monitors one or more DCI formats and the DCI formats use different TDRA tables, the set R is generated based on all TDRA tables.

[0332] - Step 0: M A,c Initialize to the empty set. Initialize k to 0. Initialize j to 0.

[0333] - Step 1: Select the kth largest K1 value from the established K1 set. (For example, if k=0, select the largest K1 value from the K1 set, and if k=1, select the second largest K1 value from the K1 set.) The above K1 value is K 1,k It is said.

[0334] - Step 2: If, K 1,k Slot corresponding to the value (slot nK 1,k ) If the symbol corresponding to the start symbol and length information (SLIV) belonging to each row of set R overlaps with a symbol set as uplink in the upper layer, the row can be excluded from set R.

[0335] - Step 3-1 (If the UE has only the UE capability to receive at most one unicast PDSCH in one slot): If the above-determined set R is not an empty set, then the set M A,c Add j as a new PDSCH reception candidate opportunity. Upon receiving one of the PDSCH candidates of the set R, the terminal can place the HARQ-ACK of the one PDSCH in the new PDSCH candidate opportunity j. Increment j by 1.

[0336] - Step 3-2 (If the terminal has the capability to receive more than one unicast PDSCH in one slot) Set M for the SLIV that ends earliest in the above-determined set R and the SLIVs that overlap in time with that SLIV. A,c Add j as a new PDSCH reception candidate opportunity. Upon receiving one of the PDSCH candidates with the SLIV, the terminal can place the HARQ-ACK of the one PDSCH in the new PDSCH candidate opportunity j. Increment j by 1. Exclude the SLIVs from the set R. Step 3-2 is repeated until the set R is empty.

[0337] - Step 4: Increase k by 1. If k is less than the cardinality of the K1 set, start again from Step 2. If k is equal to or greater than the cardinality of the K1 set, pseudo-code 1 ends.

[0338] FIG. 11a, FIG. 11b, and FIG. 11c are diagrams illustrating a Type-1 HARQ-ACK codebook for HARQ-ACK transmission of PDSCH according to one embodiment of the present disclosure.

[0339] Referring to FIGS. 11a, 11b, and 11c, a terminal performs PUCCH transmission including HARQ-ACK information in slot n. The HARQ-ACK information may be generated in the form of a Type-1 HARQ-ACK codebook.

[0340] The terminal can receive uplink / downlink configuration information from the base station. Based on the uplink / downlink configuration information, the terminal can determine whether a symbol is an uplink symbol, a downlink symbol, or a flexible symbol. For convenience, only uplink symbols are described here, and symbols other than uplink symbols may be downlink symbols or flexible symbols. Referring to Fig. 11a, all symbols in slot n and slot n-1 can be set as uplink symbols. In addition, the last two symbols in slot n-2 can be set as uplink symbols.

[0341] Assume that the terminal is set to K1=2 and K1=3 as K1 values. That is, the K1 set is {2,3}. In addition, the TDRA table of the DCI format monitored by the terminal can include five rows as shown in Table 24. For reference, each row can be set to a K0 value, a SLIV value, or a PDSCH mapping type value, but for convenience of explanation, the PDSCH mapping type is omitted.

[0342]

[0343] The terminal may include each SLIV row of the TDRA table in Table 24 in the set R according to the preparation stage. Table 24 shows the SLIVs according to each row. The terminal determines the PDSCH reception candidate opportunity M based on the K1 value and the set R. A,c can be determined. Referring to FIGS. 11a, 11b, and 11c, pseudo code 1 can be interpreted as follows. In the following description, it is assumed that the terminal has the capability to receive more than one unicast PDSCH in one slot.

[0344] - Step 0: M A,c Initialize to the empty set. Initialize k to 0. Initialize j to 0.

[0345] - Step 1: Select the k=0th largest K1 value from the established K1 set. The above K1 value is K 1,0 =3.

[0346] - Step 2: If slot nK 1,0 = If the symbol corresponding to the start symbol and length information (SLIV) belonging to each SLIV row of set R in n-3 overlaps with a symbol set as uplink in a higher layer, the SLIV row can be excluded from set R. Referring to FIG. 11b, if some symbols in slot n-3 are semi-static UL symbols set in a higher layer, the SLIV row including SLIVs overlapping with the symbols can be excluded from set R. Referring to FIG. 11b, since no semi-static UL symbol is set in slot n-3, all SLIV rows may not be excluded from set R. Set R may include {1, 2, 3, 4, 5}.

[0347] - Step 3-2 (if the terminal has the capability to receive more than one unicast PDSCH in one slot):

[0348] * Set M for the SLIV that ends earliest in the above-determined set R and the SLIVs that overlap in time with that SLIV A,c Add j=0 as a new PDSCH reception candidate opportunity. Here, the SLIV that ends first is SLIV1 (0,4) in row 1, and the SLIVs that overlap with the above SLIV are SLIV2 (0,7) in row 2 and SLIV5 (0,14) in row 5. Therefore, M A,c Adding j=0 to the terminal, when the terminal receives a PDSCH scheduled as SLIV1(0,4) of row 1, SLIV2(0,7) of row 2, or SLIV5(0,14) of row 5 in slot n-3, it sends the HARQ-ACK of the PDSCH to the first (j=0) M in the type-1 HARQ-ACK codebook. A,c can be included in the corresponding position. j is increased by 1 so that j = 1. In the set R, the SLIV rows of rows 1, 2, and 5 are excluded, so R = {3, 4}. Since the set R is not an empty set, step 3-2 is repeated.

[0349] * Set M for the SLIV that ends earliest in the above-determined set R and the SLIVs that overlap in time with that SLIV A,c Add j=1 as a new PDSCH reception candidate opportunity. Here, the SLIV that ends first is SLIV4 (7,4) in row 4, and the SLIV that overlaps with the above SLIV is SLIV3 (7,7) in row 3. Therefore, M A,c Adding j=1 to , when the terminal receives a PDSCH scheduled as SLIV4 (7,4) of row 4 or SLIV3 (7,7) of row 3 in slot n-3, it sends the HARQ-ACK of the PDSCH to the second (j=1) M in the type-1 HARQ-ACK codebook. A,ccan be included in the corresponding position. By increasing j by 1, j=2. SLIV of rows 3 and 4 are excluded from the set R, so R becomes an empty set. Therefore, step 3-2 can be terminated.

[0350] - Step 4: Increase k by 1 to make k = 1. Since the size (cardinality) of the K1 set is 2, start again from step 2 using the next K1 value. Now, K 1,1 =2.

[0351] - Step 2: If slot nK 1,1 = If the symbol corresponding to the start symbol and length information (SLIV) belonging to each row of set R in n-2 overlaps with a symbol set as uplink in a higher layer, the row can be excluded from set R. Referring to FIG. 11b, if some symbols in slot n-2 are semi-static UL symbols set in a higher layer, rows including SLIVs overlapping with the symbols can be excluded from set R. Referring to FIG. 11b, a semi-static UL symbol is set in slot n-2, and the rows overlapping with the semi-static UL symbols are row 3 and row 5. Therefore, SLIV row 3 and SLIV row 5 can be excluded from set R. Set R can include {1, 2, 4}.

[0352] - Step 3-2 (if the terminal has the capability to receive more than one unicast PDSCH in one slot):

[0353] * Set M for the SLIV that ends earliest in the above-determined set R and the SLIVs that overlap in time with that SLIV A,c Add j=2 as a new PDSCH reception candidate opportunity. Here, the SLIV that ends first is SLIV 1 (0,4) in row 1, and the SLIV that overlaps with the above SLIV is SLIV 2 (0,7) in row 2. Therefore, M A,cAdding j=2 to the terminal, when the terminal receives the PDSCH scheduled with SLIV 1(0,4) of row 1 or SLIV 2(0,7) of row 2 in slot n-3, the terminal sends the HARQ-ACK of the PDSCH to the third (j=2) M in the type-1 HARQ-ACK codebook. A,c can be included in the corresponding position. j is increased by 1 so that j = 3. In set R, SLIVs in rows 1 and 2 are excluded so that R = {4}. Since set R is not an empty set, step 3-2 is repeated.

[0354] * Set M for the SLIV that ends earliest in the above-determined set R and the SLIVs that overlap in time with that SLIV A,c Add j=3 as a new PDSCH reception candidate opportunity. Here, the SLIV that ends first is SLIV 4 (7,4) in row 4, and there is no SLIV that overlaps with the above SLIV. Therefore, M A,c Adding j=3 to the terminal, when the terminal receives the PDSCH scheduled to SLIV 4(7,4) of row 4 in slot n-3, it sends the HARQ-ACK of the PDSCH to the fourth (j=3) M in the type-1 HARQ-ACK codebook. A,c can be included in the corresponding position. By increasing j by 1, j=4. SLIV of row 4 is excluded from set R, so R becomes an empty set. Therefore, step 3-2 can be terminated.

[0355] - Step 4: Increase k by 1 so that k=2. Since k=1 means that the size (cardinality) of the K1 set is 2, the pseudo-code ends.

[0356] Referring to FIG. 11c, the terminal has M corresponding to four PDSCH reception candidate opportunities j=0, j=1, j=2, j=3. A,c can be determined. Here, M corresponding to j=0 and j=1 A,Care the PDSCH reception candidate opportunities of slot n-3, and M corresponding to j=2 and j=3. A,C are PDSCH reception candidate opportunities of slot n-2. The size of the Type-1 HARQ-ACK codebook can be determined according to the number of PDSCH reception candidate opportunities. The actual number of bits per PDSCH reception candidate opportunity can be determined according to the number of transport blocks included in each PDSCH, the number of code block groups (CBGs) included in each PDSCH, and spatial bundling settings.

[0357] [Example 1: PDSCH processing according to UE capability]

[0358] As an example of the present disclosure, a terminal can design a HARQ-ACK codebook according to terminal capability (UE capability).

[0359] UE capability can be a set of functions available depending on the terminal manufacturer's implementation. When connecting to a cell, a terminal can report its capabilities to the base station. This can be called a UE capability report. The base station can obtain the capabilities of a UE connected to its cell (RRC connected UE) through the UE's UE capability report.

[0360] According to the present disclosure, a terminal can transmit one of the following terminal capabilities to a base station through a terminal capability report.

[0361] Terminal capabilities allow a terminal to report the maximum number of PDSCHs it can process in a single slot. Processing here can refer to a series of processes that receive a PDSCH and generate a HARQ-ACK indicating whether the PDSCH was successfully received.

[0362] For example, if a terminal can report its capability to process up to N PDSCHs in one slot through a terminal capability report, and a base station schedules more than N PDSCHs in one slot to the terminal, the terminal cannot receive more than N PDSCHs in one slot. In other words, it is desirable for the base station to schedule up to N PDSCHs in one slot to the terminal, and it is desirable not to schedule more than N PDSCHs in one slot.

[0363] Note that the PDSCHs scheduled here may not overlap in the time domain. That is, if N PDSCHs are scheduled in one slot, the N PDSCHs may not overlap in the time domain and may be located in different symbols.

[0364] Note that N can have at least one of the values ​​1, 2, 4, or 7.

[0365] For reference, in the present disclosure, terminal capability includes the maximum number of PDSCHs that can be processed in a single slot. However, terminal capability may include the maximum number of PDSCHs that can be processed in a specific time interval (e.g., a mini-slot, multiple slots, etc.) rather than a single slot. In this case, in the embodiments of the present disclosure, the term "slot" may be interpreted as a specific time interval.

[0366] According to one embodiment of the present disclosure, when a base station schedules more than N PDSCHs, for example, M (M>N) PDSCHs, to a terminal in one slot, the operation of the terminal may be at least one of the following.

[0367] In the first method, the terminal can select N PDSCHs from among M PDSCHs and receive the N PDSCHs.

[0368] Here, the terminal can select N PDSCHs in chronological order among M PDSCHs. More specifically, the terminal can select N PDSCHs scheduled in the earliest symbol in chronological order among the M PDSCHs. The terminal can determine the indices of the symbols in which the PDSCHs are scheduled in the slot. Here, the indices of the first symbol or the last symbol in which the PDSCHs are scheduled can be determined. The terminal can select N PDSCHs having the lowest indices (the earliest symbol in chronological order) among the symbol indices of the M PDSCHs and process the N PDSCHs.

[0369] Here, N PDSCHs can be selected according to the time order of DCIs corresponding to M PDSCHs. More specifically, N PDSCHs corresponding to DCIs positioned later in time among DCIs corresponding to M PDSCHs can be selected. The terminal can determine the index of the slot in which the DCI for scheduling the PDSCH (the DCI corresponding to the PDSCH) is to be located, or the index of the symbol within the slot. Here, the DCI can be received through the PDCCH, and the terminal can determine the index of the slot in which the PDCCH is received, or the index of the symbol in which the PDCCH is received within the slot (if the PDCCH has multiple symbols, the first symbol of the PDCCH or the last symbol of the PDCCH). The terminal can determine the N DCIs positioned later in time among the DCIs corresponding to M PDSCHs. This is because, when the base station schedules the terminal with DCI later, information included in the PDSCH scheduled later may be more important.

[0370] Here, when selecting N PDSCHs to be processed by the UE, among M PDSCHs, PDSCHs scheduled with DCI (Downlink control information) may be preferentially included. PDSCHs can be scheduled in two ways. First, PDSCHs can be scheduled with DCI. The UE can receive a PDCCH, and the PDCCH can include DCI. The DCI can include scheduling information of the PDSCH. For reference, the DCI including the scheduling information of the PDSCH can be one of DCI format 1_0, DCI format 1_1, DCI format 1_2, and DCI format 1_3. Second, PDSCHs can be periodically scheduled through higher layer signals. A PDSCH scheduled in this way can be called an SPS PDSCH. Unlike a PDSCH scheduled with DCI, an SPS PDSCH may not have a corresponding DCI. Therefore, the base station cannot dynamically control the scheduling information of the SPS PDSCH to the UE. Therefore, it is possible to prioritize PDSCHs scheduled with DCI that can be dynamically controlled through DCI.

[0371] Here, when selecting N PDSCHs to be processed by the terminal, among the M PDSCHs, PDSCHs scheduled as upper-layer signals can be preferentially included. PDSCHs can be scheduled in two ways. In the case of the SPS PDSCH, it can include information that must be transmitted periodically. This information may be essential for the upper layer (e.g., application layer). In other words, the base station can transmit important information through the SPS PDSCH. Therefore, the SPS PDSCH can be prioritized.

[0372] Here, when selecting N PDSCHs to be processed by a terminal, PDSCHs with higher priorities among M PDSCHs can be preferentially included. The terminal can determine the priority of each PDSCH. This priority can be dynamically indicated in the DCI that schedules the PDSCH or set in a higher layer signal. The priority can be '0' or '1', where '0' can correspond to a PDSCH with a lower priority and '1' can correspond to a PDSCH with a higher priority. The terminal can preferentially select PDSCHs with higher priorities among M PDSCHs (i.e., PDSCHs with priorities corresponding to '1'). This is because PDSCHs with higher priorities can convey more important information.

[0373] Here, when selecting N PDSCHs to be processed by the terminal, the terminal can select DCIs corresponding to M PDSCHs based on scrambled RNTIs. That is, the terminal can preferentially include PDSCHs corresponding to DCIs scrambled with a specific RNTI. For example, the DCI corresponding to the PDSCH can be scrambled with C-RNTI, CS-RNTI, or MCS-C-RNTI. Here, the MCS-C-RNTI is an RNTI used to transmit the PDSCH with higher reliability, and the CS-RNTI can be used for activating or retransmitting the SPS PDSCH. The terminal can prioritize the DCI scrambled with MCS-C-RNTI. That is, the terminal can preferentially select PDSCHs corresponding to DCIs scrambled with MCS-C-RNTI. In addition, the terminal can prioritize the DCI scrambled with C-RNTI. That is, the terminal can preferentially select PDSCHs corresponding to DCI scrambled with C-RNTI. The system information block can be transmitted on a PDSCH scheduled with DCI scrambled with SI-RNTI. If there is a DCI scrambled with SI-RNTI, the terminal can give top priority to the PDSCH scheduled by the DCI and include it in the N PDSCHs. That is, the terminal can definitely receive the PDSCH including the system information block.

[0374] Here, when the terminal selects N PDSCHs to process, the terminal can preferentially select a PDSCH with a lower index corresponding to the PDSCH among the M PDSCHs. In the case of an SPS PDSCH, a unique index can be assigned to the SPS PDSCH. For example, a higher layer signal configuring the SPS PDSCH can include a unique index for the SPS PDSCH. Different SPS PDSCHs in one slot can correspond to different unique indices. That is, the terminal can preferentially select SPS PDSCHs with lower indices. This allows the base station to prioritize reception of the SPS PDSCH by transmitting more important information to the SPS PDSCH with a lower index among the information transmitted to the SPS PDSCH.

[0375] Here, when selecting N PDSCHs to be processed by the terminal, the terminal can preferentially select PDSCHs transmitted for broadcast or multicast purposes among M PDSCHs. The terminal can determine whether the PDSCH is transmitted for one of the purposes of unicast, broadcast, or multicast. This can be determined based on the DCI format in which the PDSCH is scheduled, the scrambled RNTI, or the upper layer configuration of the PDSCH. The terminal can receive a PDSCH transmitted for unicast purposes through retransmission, but it may be difficult to retransmit a PDSCH transmitted for broadcast or multicast purposes. Therefore, the terminal can avoid unnecessary retransmission of a PDSCH transmitted for broadcast or multicast purposes by preferentially receiving a PDSCH transmitted for broadcast or multicast purposes.

[0376] A terminal may select N PDSCHs based on an implementation based on an embodiment. Here, selection based on implementation does not mean defining a single selection method, but rather implementing a method for selecting N PDSCHs based on the terminal manufacturer's convenience. This implementation method may be determined by one or a combination of the methods described above.

[0377] In this method, valid HARQ-ACK information of N PDSCHs selected by the terminal may be transmitted to the base station. In addition, valid HARQ-ACK information for MN PDSCHs that are not selected may not be transmitted to the base station. In other words, the terminal may transmit NACK to the base station for MN PDSCHs or may not transmit HARQ-ACK information for MN PDSCHs. Even if the terminal transmits ACK to the base station for MN PDSCHs, the base station may determine that the HARQ-ACK information of the PDSCHs is invalid. The base station determining that it is invalid may be the same as determining it with NACK.

[0378] In a second method, if a terminal is scheduled with more than N PDSCHs in a single slot, the terminal may not process any PDSCHs other than a specific PDSCH in the slot. Here, the number of specific PDSCHs need not be N and may be equal to or less than N. In other words, the terminal can only receive the PDSCHs that it must receive. The specific PDSCHs may be as follows.

[0379] A terminal can receive PDSCHs with higher priorities among PDSCHs scheduled in a slot. The terminal may not receive PDSCHs with lower priorities among PDSCHs scheduled in a slot. This can be done when the number of high-priority PDSCHs is less than or equal to the maximum number of PDSCHs that the terminal can process in a slot. This is an operation in which the terminal considers receiving only high-priority PDSCHs based solely on priorities, and thus the terminal can exclude some or all of the low-priority PDSCHs from being included.

[0380] Among the PDSCHs scheduled in a slot, the terminal can receive PDSCHs (PDSCHs containing system information blocks) scheduled with DCI scrambled with SI-RNTI. PDSCHs scheduled with DCI scrambled with other RNTIs may not be received. In other words, the terminal receives only the PDSCHs that transmit the most important information.

[0381] A terminal can only receive PDSCHs scheduled with DCI among the PDSCHs scheduled in a slot. The terminal may not receive SPS PDSCHs among the PDSCHs scheduled in a slot. This can be done when the number of PDSCHs scheduled with DCI is less than or equal to the maximum number of PDSCHs that the terminal can process in a slot. This can be applied under the assumption that the information transmitted on the SPS PDSCH has a lower priority than the information included in the PDSCH scheduled with DCI.

[0382] A terminal can only receive SPS PDSCHs among the PDSCHs scheduled in a slot. The terminal may not receive PDSCHs scheduled with DCI among the PDSCHs scheduled in a slot. This can be done when the number of SPS PDSCHs is less than or equal to the maximum number of PDSCHs that the terminal can process in a slot. This can be applied under the assumption that the information transmitted on the PDSCH scheduled with DCI has a lower priority than the information included in the SPS PDSCH.

[0383] In a third method, if a terminal schedules more than N PDSCHs in a single slot, the terminal may not process all PDSCHs in the slot. That is, if more than N PDSCHs are scheduled in a single slot, the terminal may not receive all PDSCHs scheduled in that slot. In addition, the terminal may transmit a NACK to the base station as HARQ-ACK information for the PDSCHs.

[0384] This method can be advantageous in terms of terminal implementation, as when a base station requests a terminal to process a number of PDSCHs exceeding its terminal's capacity in a single slot, the terminal ignores the base station's scheduling that exceeds its terminal's capacity. While the first and second methods both require the terminal to select N PDSCHs to process in a single slot, the third method can reduce the terminal's implementation complexity by not processing all scheduled PDSCHs.

[0385] In the method described above, the terminal selects a PDSCH according to the terminal capability. Here, it is assumed that the terminal can process up to N PDSCHs in one slot based on the terminal capability. Even though the terminal can process up to N PDSCHs, the base station can configure the terminal to process a number of PDSCHs less than N in one slot. The base station can configure this to reduce the power consumption of the terminal. The base station can configure this according to the implementation of the base station scheduler. In other words, the base station can configure the terminal to process up to K ( <N)개의 PDSCH를 처리하도록 설정할 수 있다. 여기서 K는 상위 계층 신호로 단말에게 설정될 수 있는 값일 수 있다. 예를 들어, 단말이 한 슬롯에 최대 N=7개의 PDSCH를 처리할 수 있는 단말 능력을 기지국으로 전송하면, 기지국은 K=4를 단말에게 설정할 수 있다. 이 경우, 단말의 동작은 한 슬롯에서 최대 K개의 PDSCH만 수신하는 것으로 변경될 수 있다. 단말은, 앞서 서술한 방법에서, N은 K로 대체하여 적용할 수 있다.

[0386] [Example 2: HARQ-ACK Codebook Design Based on UE Capability]

[0387] In this disclosure, a method for designing a HARQ-ACK codebook based on terminal capabilities is described.

[0388] For convenience of description, it is assumed that the terminal can process up to N PDSCHs in one slot based on the terminal's capability. For reference, the terminal can process up to N PDSCHs in one slot, but the base station can set the maximum number of PDSCHs that the terminal can process in one slot. If the terminal receives the above setting, N in the following description of the present disclosure is the maximum number of PDSCHs that the base station sets for the terminal in one slot. If the terminal does not receive the above setting, N is the maximum number of PDSCHs that can be processed in one slot determined according to the terminal's capability.

[0389] To design a HARQ-ACK codebook based on terminal capabilities, the terminal can receive the following information from the base station. The following information can be set through the base station's upper layer signal (RRC signal).

[0390] As the first information, the terminal can receive K1 values ​​from the base station. The K1 value represents the offset between the PDSCH reception slot and the slot in which the HARQ-ACK is transmitted. The terminal can receive one or more K1 values ​​from the base station. These K1 values ​​can be collectively referred to as a K1 set.

[0391] As a second piece of information, the terminal can be configured to specify the maximum number of PDSCHs it can process in a single slot. As described above, in the absence of this configuration, the terminal can use the maximum number of PDSCHs it can process in a single slot, determined based on its capabilities.

[0392] A terminal may have multiple terminal capabilities. For example, the maximum number of PDSCHs that a terminal can process in one slot may vary depending on PRB allocation. For example, a terminal may process at most N1 PDSCHs having PRBs less than or equal to 136, and at most N2 PDSCHs having PRBs greater than 136. When such multiple terminal capabilities are present, the terminal may determine the maximum number of PDSCHs that can be processed in one slot based on the larger terminal capability (i.e., the larger value between N1 and N2) or the smaller terminal capability (i.e., the smaller value between N1 and N2).

[0393] FIG. 12a and FIG. 12b are diagrams illustrating HARQ-ACK codebook generation according to terminal capabilities according to one embodiment of the present disclosure.

[0394] Referring to Fig. 12a, a terminal may transmit a PUCCH in slot n. The PUCCH may include a HARQ-ACK codebook. The HARQ-ACK codebook may include one or more HARQ-ACK bit(s), and each HARQ-ACK bit may have a corresponding slot and a corresponding PDSCH occasion. In other words, when a terminal receives a PDSCH, the position of the HARQ-ACK bit of the PDSCH in the HARQ-ACK codebook may be determined based on the slot of the PDSCH and the PDSCH occasion.

[0395] For convenience, in this disclosure, it is assumed that the HARQ-ACK bit corresponding to one PDSCH is 1 bit. However, if the PDSCH includes at most 2 TBs (transport blocks), the HARQ-ACK bit corresponding to the PDSCH may be 2 bits, and if the PDSCH includes at most X CBGs (codeblock groups), the HARQ-ACK bits corresponding to the PDSCH may be X bits.

[0396] When a terminal transmits a PUCCH in slot n, the HARQ-ACK codebook of the PUCCH may include HARQ-ACK bit(s) corresponding to PDSCHs received in slots n-k1. Here, k1 may be one of the K1 values ​​set as the first information. For example, assume that there are four K1 values ​​set as the first information (k1_0, k1_1, k1_2, k1_3). In this case, the HARQ-ACK codebook of the PUCCH may include HARQ-ACK bit(s) corresponding to PDSCHs received in slots n-k1_0, n-k1_1, n-k1_2, and n-k1_3.

[0397] Referring to Fig. 12a, it can be assumed that the terminal is set to have K1 values ​​of k1_0=3 and k1_1=2. Therefore, slots n-k1_0=n-3 and slots n-k1_1=n-2 are slots that should be included in the HARQ-ACK codebook to be transmitted in slot n. The slots that should be included in the HARQ-ACK codebook may mean that the HARQ-ACK information of the PDSCH received in the slot should be included in the HARQ-ACK codebook.

[0398] Note that PDSCHs may be repeatedly transmitted across multiple slots. In this case, the embodiments of the present disclosure may be applied based on the last PDSCH transmitted.

[0399] Referring to FIG. 12A, the maximum number of PDSCHs (second information) that a terminal can receive in one slot may be N=2. In this case, the terminal may be scheduled for N=2 PDSCHs in one slot. For example, the terminal may be scheduled for PDSCH#1 and PDSCH#2 in slot n-3, and may be scheduled for PDSCH#3 and PDSCH#4 in slot n-2. This is just an example, and the terminal may be scheduled for only one PDSCH in each slot, or may be scheduled for none. In addition, if the terminal is scheduled for N=2 or more PDSCHs in one slot, the terminal may determine N PDSCHs to receive using the first embodiment above.

[0400] Each slot can have N PDSCH occasions. N is the maximum number of PDSCHs that can be processed in a slot determined according to the second information. That is, up to N PDSCHs can be scheduled in each slot. Therefore, each slot can include N HARQ-ACK bits corresponding to the N PDSCHs in each slot. For example, slot n-k1_0 can include N HARQ-ACK bits. This is b0 0, b 0 1, ..., b 0 N-1 Let n-k1_1 be a slot that can contain N HARQ-ACK bits. This is b 1 0, b 1 1, ..., b 1 N-1 Let n-k1_2 be a slot that can contain N HARQ-ACK bits. This is b 2 0, b 2 1, ..., b 2 N-1 Let n-k1_3 be a slot that can contain N HARQ-ACK bits. This is b 3 0, b 3 1, ..., b 3 N-1 Let be. Therefore, the HARQ-ACK codebook containing the PUCCH of slot n is [b 0 0, b 0 1, ..., b 0 N-1 , b 1 0, b 1 1, ..., b 1 N-1 , b 2 0, b 2 1, ..., b 2 N-1 , b 3 0, b 3 1, ..., b 3 N-1 ]. The size of the HARQ-ACK codebook (payload size) can be equal to the product of the number of K1 values ​​included in the total K1 set and the maximum number of PDSCHs (N) that can be processed in one slot.

[0401] Note that this is for a single cell. If multiple cells are configured for a terminal, the terminal can generate a HARQ-ACK codebook for each cell and combine them in ascending order of cell index to create a single HARQ-ACK codebook. Note that when multiple cells are configured, different K1 values ​​and different N values ​​can be set for each cell.

[0402] For reference, the base station can set the maximum number of PDSCHs that can be processed in one slot for multiple cells to the terminal. For example, if A cells are set for the terminal, N can be set as the maximum number of PDSCHs that can be processed in one slot of the A cells. In this case, the terminal can generate N PDSCH occasions in one slot of the A cells. The terminal can receive a PDSCH in one slot of one of the A cells. The received PDSCH can correspond to one of the N PDSCH occasions. Here, each of the N PDSCH occasions may not be restricted by the cell to which it belongs (corresponds). That is, a PDSCH occasion may correspond to a PDSCH received in a first cell or may correspond to a PDSCH received in a second cell.

[0403] For reference, the base station can set the maximum number of PDSCHs that can be processed in one slot for multiple cell sets to the terminal. That is, the first maximum number of PDSCHs can be set for the first cell set, and the second maximum number of PDSCHs can be set for the second cell set. In this case, the terminal can generate a first HARQ-ACK codebook based on the first maximum number of PDSCHs for the cells included in the first cell set, generate a second HARQ-ACK codebook based on the second maximum number of PDSCHs for the cells included in the second cell set, and generate a HARQ-ACK codebook by combining the first HARQ-ACK codebook and the second HARQ-ACK codebook.

[0404] Referring to Fig. 12b, since the number of PDSCHs that can be processed in one slot is 2 (N=2), the terminal can generate two PDSCH occasions per slot corresponding to the K1 value. Since the K1 values ​​are 3 and 2, 1 for slot n-3 st PDSCH occasion, 2 nd PDSCH occasion, and 3 for slot n-2 rd PDSCH occasion, 4 th PDSCH occasions can be generated. And each PDSCH occasion can have a corresponding HARQ-ACK bit. Therefore, 4 HARQ-ACK bits [b] corresponding to each of the 4 PDSCH occasions 0 0, b 0 1, b 1 0, b 1 1] may exist. Here b 0 0, b 0 1 is for slot n-3 st PDSCH occasion and 2 nd HARQ-ACK bits of PDSCH occasion, b 1 0, b 1 1 is for slot n-2rd PDSCH occasion and 4 th These are the HARQ-ACK bits of the PDSCH occasion.

[0405] The terminal must determine which of the N PDSCH occasions the PDSCH received in the slot corresponds to. For example, if the terminal receives a PDSCH in slot n-k1_0, the terminal determines whether the PDSCH received in the slot corresponds to one of the N PDSCH occasions of the slot (and N HARQ-ACK bits corresponding to the N PDSCH occasions, {b 0 0, b 0 1, b 0 2, b 0 3}) must be determined to which PDSCH occasion it corresponds. The terminal can determine the PDSCH occasion corresponding to the received PDSCH by at least one of the following methods.

[0406] The UE can indicate the index of the PDSCH occasion corresponding to the scheduled PDSCH in the DCI for scheduling the PDSCH. More specifically, the DCI for scheduling the PDSCH can include a field for indicating the PDSCH occasion index. The length of the field can be determined as ceiling(log2(N)) bits. The UE can obtain the index of the PDSCH occasion corresponding to the scheduled PDSCH from the field of the DCI for scheduling the PDSCH. For example, when N=4, the length of the field can be determined as 2 bits. If it is 00, the index of the corresponding PDSCH occasion is 0, if it is 01, the index of the corresponding PDSCH occasion is 1, if it is 10, the index of the corresponding PDSCH occasion is 2, and if it is 11, the index of the corresponding PDSCH occasion is 3. For reference, when N=1, the DCI may not include the field (i.e., the length of the field is 0 bit). In this case, the PDSCH occasion index corresponding to the scheduled PDSCH may be 0.

[0407] The DCI for scheduling the PDSCH may not include the above field. For example, in the case of DCI formats 1_1, 1_2, to 1_3, the DCI may include the above field, but in the case of DCI format 1_0, the field may not be included. (For reference, when the UE monitors DCI format 1_0 in the common search space, the DCI format 1_0 may not include the field, and when the UE monitors DCI format 1_0 in the UE-specific search space, the DCI format 1_0 may not include the field.) In addition, the base station may not set the field to reduce the overhead of the DCI. This may be set separately for each DCI format. Therefore, the field may not be included in one or more DCI formats among DCI formats 1_1, 1_2, to 1_3. In this case, the PDSCH occasion index corresponding to the scheduled PDSCH can be determined by at least one of the following methods.

[0408] In a first method, for a PDSCH scheduled by a DCI that does not include a field, the UE can always assume a specific index. For example, the UE can assume that the index of the PDSCH scheduled by the DCI that does not include a field is 0. As another example, the UE can assume that the index of the PDSCH scheduled by the DCI that does not include a field is N-1. As another example, the base station can configure an index to be assumed for the UE. That is, the base station can assume a specific index (e.g., index 2) set by the base station as the index of the PDSCH scheduled by the DCI that does not include a field.

[0409] In a second method, an index may be determined according to time domain allocation information of a scheduled PDSCH. For example, the DCI may include a field indicating time domain allocation information of a PDSCH. This field may be called a Time domain resource assignment (TDRA) field. The TDRA field may include a TDRA table index. An entry in the TDRA table corresponding to the TDRA table index includes information on slots or symbols for which the PDSCH is scheduled. The terminal may obtain or calculate an index of a PDSCH occasion based on the indicated TDRA table index. For example, when the TDRA table index indicated in the DCI is i, the index of the corresponding PDSCH occasion may be determined as (i mod N) or ((i-1) mod N). (i mod N) can be used when the index of the TDRA table starts from 0, and (i-1 mod N) can be used when the index of the TDRA table starts from 1.

[0410] In a third method, the index may be determined based on the symbol index of the scheduled PDSCH. For example, the terminal may determine the symbol index based on the symbol of one of the scheduled PDSCHs. For example, the terminal may determine the symbol index based on the index of the start symbol of the PDSCH or the index of the last symbol of the PDSCH. The symbol index is a symbol index within a slot, and the first symbol of the slot may be 0 and the last symbol of the slot may be 13. When the symbol index of the PDSCH scheduled for the terminal is i, the index of the corresponding PDSCH occasion may be determined as (i mod N). In another method, when the symbol index of the PDSCH scheduled for the terminal is i, if i is included in a specific symbol index range, it may be determined as a specific PDSCH occasion index. For example, when N is 4, if i is included in the symbol index interval {0~A0}, the corresponding PDSCH occasion index is 0, if i is included in the symbol index interval {A0+1~A1}, the corresponding PDSCH occasion index is 1, if i is included in the symbol index interval {A1+1~A2}, the corresponding PDSCH occasion index is 2, and if i is included in the symbol index interval {A2+1~13}, the corresponding PDSCH occasion index may be 3. Here, 0 A0 <A1<A2 It can be 13. Here, A0=3, A1=6, A2=10 or A0=2, A1=6, A2=9 or A0=3, A1=6, A2=9 or A0=2, A1=6, A2=10. In addition, A0, A1, A2 can be set from the base station to the terminal.

[0411] In a fourth method, an index may be determined based on time information at which the scheduling DCI is transmitted. For example, the terminal may determine the index of a PDSCH occasion corresponding to the PDSCH scheduled by the DCI based on the index of the slot in which the DCI for scheduling the PDSCH is transmitted. Here, the scheduling DCI may be transmitted via a PDCCH. The index of the slot in which the DCI is transmitted refers to the slot in which the PDCCH including the DCI is received. When the index of the slot is i, the terminal may determine the index of the corresponding PDSCH occasion as (i mod N). That is, the base station may schedule the PDSCH through DCI transmitted in different slots to make the PDSCH occasion index of each PDSCH different.

[0412] In a fifth method, an index may be determined based on frequency information on which the scheduling DCI is transmitted. For example, the terminal may determine the index of a PDSCH occasion corresponding to the PDSCH scheduled by the DCI based on the indices of the CCEs to which the PDCCH including the DCI on which the PDSCH is scheduled is mapped. Here, the number of CCEs to which the PDCCH is mapped may be one or more. If there are multiple CCEs, the CCE with the lowest index may be used. When the index of the CCE is i, the terminal may determine the index of the corresponding PDSCH occasion as (i mod N). That is, the base station may schedule the PDSCH through DCI transmitted on different CCEs to make the PDSCH occasion index of each PDSCH different.

[0413] In a sixth method, the index of a PDSCH occasion can be determined according to the index of the CORESET or search space in which the scheduling DCI is transmitted. For example, the UE can determine the index of the PDSCH occasion corresponding to the PDSCH scheduled by the DCI based on the index of the CORESET or search space in which the PDCCH including the DCI for scheduling the PDSCH is monitored. For reference, the PDCCH can be repeatedly transmitted in two linked search spaces. In this case, the index of the PDSCH occasion can be determined based on one search space (e.g., the search space with a lower index). When the index of the CORESET or search space is i, the index of the corresponding PDSCH occasion can be determined as (i mod N). That is, the base station can schedule the PDSCH through DCI transmitted in different CORESETs or search spaces so that the PDSCH occasion index of each PDSCH is different.

[0414] In a seventh method, a PDSCH occasion index can be determined based on the value of the HARQ process number field of the scheduling DCI. The DCI for scheduling the PDSCH can include a field indicating the HARQ process number of the scheduled PDSCH. Based on the field, the UE can obtain the HARQ process number of the scheduled PDSCH. When the HARQ process number identified by the UE is i, the index of the corresponding PDSCH occasion can be determined as (i mod N). That is, the base station can make the PDSCH occasion index different by scheduling the PDSCH through DCIs with different HARQ process numbers. Although the HARQ process number field is described here, the PDSCH occasion index can be determined based on the values ​​of other fields included in the DCI, such as TPC command for PUCCH, MCS, and RV.

[0415] A terminal may be configured to receive an SPS PDSCH in a slot. The HARQ-ACK bit of the SPS PDSCH may be included in a HARQ-ACK codebook. To include the HARQ-ACK bit of the SPS PDSCH in the HARQ-ACK codebook, the terminal must determine the index of the PDSCH occasion corresponding to the SPS PDSCH. The method for this is as follows.

[0416] In a first method, the index of a PDSCH occasion can be set in the SPS PDSCH configuration. The terminal can receive this SPS PDSCH configuration through a higher layer signal (RRC signal) of the base station. The index of the PDSCH occasion corresponding to the SPS PDSCH received according to the SPS PDSCH configuration can always be the set index.

[0417] As a second method, the index of the PDSCH occasion may be indicated in the DCI that activates the SPS PDSCH. For example, the DCI that activates the SPS PDSCH may include a field that indicates the index of the corresponding PDSCH occasion. The index of the PDSCH occasion indicated in the field may be commonly applied to all SPS PDSCHs activated by the DCI. For reference, if the DCI that activates the SPS PDSCH does not include a field, the UE may obtain or calculate the index of the PDSCH occasion corresponding to the SPS PDSCH using the methods described above for the case where the DCI does not include a field.

[0418] Referring to FIG. 12b, the terminal can determine the correspondence between the received PDSCH and the PDSCH occasion based on the index of the received PDSCH. For example, the index of PDSCH#1 received in slot n-3 may be 0 and the index of PDSCH#2 received may be 1. The two received PDSCHs correspond to two PDSCH occasions (1 st PDSCH occasion, 2 nd Each PDSCH can correspond to a different occasion. PDSCH#1 with a low index is 1 st Corresponding to the PDSCH occasion, PDSCH#2 with a high index is 2 nd can correspond to a PDSCH occasion. The index of PDSCH#3 received in slot n-2 can be 0 and the index of PDSCH#4 received can be 1. The two received PDSCHs correspond to two PDSCH occasions (3 rd PDSCH occasion, 4 th Each PDSCH can correspond to a specific occasion. PDSCH#3 with a low index is 3 rdCorresponding to the PDSCH occasion, PDSCH#4 with a high index is 4 th It can correspond to PDSCH occasion.

[0419] FIG. 13 is a diagram showing a terminal according to one embodiment of the present disclosure receiving two or more PDSCHs with the same index in one slot.

[0420] Referring to FIG. 13, a terminal can be scheduled for three PDSCHs in one slot. For reference, it can be assumed that the terminal has the capability to process three or more PDSCHs in one slot. However, the base station can set a number lower than 3 (e.g., N=2) as the second information. Two of the three PDSCHs (PDSCH#1, PDSCH#2) can have the same index 0, and the other PDSCH (PDSCH#3) can have the index 1. Since the HARQ-ACK codebook according to the terminal capability is N=2, it can include two PDSCH occasions. In this case, the terminal must determine how the two PDSCHs (PDSCH#1, PDSCH#2) with the same index correspond to the PDSCH occasion.

[0421] A terminal can only be scheduled for one PDSCH corresponding to a single PDSCH occasion. That is, if two or more PDSCHs correspond to a PDSCH occasion, the terminal may consider this an error case.

[0422] When there are multiple PDSCHs corresponding to one PDSCH occasion, the terminal can generate a HARQ-ACK bit corresponding to the PDSCH occasion in at least one of the following ways.

[0423] Referring to FIG. 13A, in a first method, a terminal may select one of a plurality of PDSCHs. When generating a HARQ-ACK codebook, the terminal may include the HARQ-ACK bit of the selected PDSCH in the HARQ-ACK bit position of the corresponding PDSCH occasion. For example, the terminal may select a PDSCH based on time (scheduled symbol position) among the PDSCHs. The terminal may select the PDSCH that is earliest in time (the earliest scheduled symbol). For example, the terminal may select the most recently scheduled PDSCH. That is, the terminal may select the PDSCH corresponding to the most recently received DCI among the DCIs that schedule the plurality of PDSCHs. For example, the terminal may select a PDSCH scheduled as a DCI among the plurality of PDSCHs. That is, if a PDSCH scheduled with DCI and an SPS PDSCH correspond to the same PDSCH occasion, the UE can select the PDSCH scheduled with DCI. For example, the UE can select one PDSCH based on the HARQ process number values ​​of multiple PDSCHs. That is, the UE can select the PDSCH with the lowest HARQ process number value. For example, if multiple PDSCHs are SPS PDSCHs, the UE can select the PDSCH based on the index of the SPS PDSCH (the index included in the SPS PDSCH configuration information). That is, the UE can select the SPS PDSCH with the lowest index.

[0424] Referring to FIG. 13b, in the second method, the terminal may include an ACK in the HARQ-ACK codebook as the corresponding HARQ-ACK bit when all PDSCHs corresponding to one PDSCH occasion are successfully received, and may include a NACK in the HARQ-ACK codebook as the corresponding HARQ-ACK bit when at least one of the PDSCHs corresponding to one PDSCH occasion fails to be received. In other words, the terminal may obtain or calculate HARQ-ACK bits of PDSCHs corresponding to one PDSCH occasion, and binary-bundle the HARQ-ACK bits to generate one HARQ-ACK bit. Here, binary bundling may be an operation of determining that if all HARQ-ACK bits are ACK, it is ACK, and otherwise, it is NACK.

[0425] In the second method, the terminal receives all PDSCHs corresponding to one PDSCH occasion and generates corresponding HARQ-ACK bits. Based on the first method, the terminal receives some of the PDSCHs corresponding to one PDSCH occasion, and when all of the some PDSCHs are successfully received, the terminal can include an ACK in the HARQ-ACK codebook with the HARQ-ACK bits corresponding to one PDSCH occasion to which the some PDSCHs correspond. In addition, when at least one of the some PDSCHs fails to be received, the terminal can include a NACK in the HARQ-ACK codebook with the HARQ-ACK bits corresponding to one PDSCH occasion to which the some PDSCHs correspond.

[0426] Referring to FIG. 13c, in a third method, if there are multiple PDSCHs corresponding to a single PDSCH occasion, the terminal can include a NACK as the HARQ-ACK bit of the PDSCH occasion in the HARQ-ACK codebook. That is, if multiple PDSCHs correspond to a PDSCH occasion, the terminal can generate a NACK without receiving the multiple PDSCHs.

[0427] FIG. 14 is a diagram illustrating a change in a HARQ-ACK codebook according to the maximum number of PDSCHs that can be processed in one slot according to one embodiment of the present disclosure.

[0428] Let us assume that the maximum number of PDSCHs that a terminal can process in one slot is greater than or equal to 2. In this case, the base station can indicate to the terminal the maximum number of PDSCHs that can be processed in one slot as 1 or 2. Referring to Fig. 14, if the base station schedules one PDSCH for each slot to the terminal and indicates to the terminal the maximum number of PDSCHs that can be processed in one slot as 2, the terminal generates two PDSCH occasions per slot. The HARQ-ACK codebook will contain two HARQ-ACK bits per slot. However, if the maximum number of PDSCHs that the terminal can process is indicated as 2, the terminal generates one PDSCH occasion per slot. Therefore, the HARQ-ACK codebook will contain only one HARQ-ACK bit per slot. Therefore, if the maximum number of PDSCHs that a terminal can process is instructed to match the number of PDSCHs actually scheduled, the terminal can generate a HARQ-ACK codebook more efficiently.

[0429] The size of the HARQ-ACK codebook is determined by the maximum number of PDSCHs that can be processed in a single slot (second information). The base station may change the maximum number of PDSCHs that can be processed in a single slot based on terminal traffic information, scheduler implementation, and other reasons. The change may be communicated via DCI, MAC-CE, or RRC signals.

[0430] When transmitted via DCI, it can be determined in at least one of the following two ways:

[0431] In a first method, the DCI for scheduling PDSCHs may include a configuration of the maximum number of PDSCHs that can be processed in one slot. The terminal may be configured with the maximum number of PDSCHs that can be processed in one slot through the DCI for scheduling PDSCHs, and may generate a HARQ-ACK codebook based on the value. The terminal may expect that the DCI for scheduling PDSCHs corresponding to the same HARQ-ACK codebook will always have the same value set. That is, the base station must include the same value (the maximum number of PDSCHs that can be processed in one slot) in the DCI for scheduling PDSCHs corresponding to the same HARQ-ACK codebook. By receiving at least one DCI, the terminal may determine the size of the HARQ-ACK codebook to which the HARQ-ACK bits of the PDSCH scheduled by the DCI correspond.

[0432] Information about setting the maximum number of PDSCHs that can be processed in one slot in DCI may be included as follows:

[0433] DCI may include a 1-bit field. If the 1-bit is '0', the terminal may schedule up to 1 PDSCH per slot. If the 1-bit is '1', the maximum number of PDSCHs that the terminal may schedule per slot may be a value set in a higher layer signal (RRC signal) or a value determined according to the terminal's capabilities.

[0434] The DCI may include a 1-bit field. If the 1-bit is '0', the first value may be determined as the maximum number of PDSCHs that can be scheduled in one slot. If the 1-bit is '1', the second value may be determined as the maximum number of PDSCHs that can be scheduled in one slot. Here, the first value and the second value may be two values ​​among 1, 2, 4, and 7. As another example, the base station may set values ​​corresponding to the first value and the second value to the terminal.

[0435] The DCI may include a 2-bit field. If the 2-bit field is '00', the terminal may use the maximum number of PDSCHs that can be scheduled in one slot used in the previous HARQ-ACK codebook to generate the HARQ-ACK codebook of the currently scheduled PDSCH. That is, the same size as the previous HARQ-ACK codebook may be maintained. If the 2-bit field is '01', the terminal may use a lower number than the maximum number of PDSCHs that can be scheduled in one slot used in the previous HARQ-ACK codebook to generate the HARQ-ACK codebook of the currently scheduled PDSCH. That is, the terminal may generate a HARQ-ACK codebook of a smaller size compared to the previous HARQ-ACK codebook. If the 2-bit field is '10', the terminal may use a higher number than the maximum number of PDSCHs that can be scheduled in one slot used in the previous HARQ-ACK codebook to generate the HARQ-ACK codebook of the currently scheduled PDSCH. That is, the terminal can generate a HARQ-ACK codebook of a larger size compared to the previous HARQ-ACK codebook. Here, the lower and higher numbers can be numbers that decrease or increase by 1, or can be fixed values. For example, the maximum number of PDSCHs that can be scheduled in one slot can be determined as one of the values ​​{1, 2, 4, 7}.

[0436] The DCI may include a 2-bit field. If the 2-bit is '00', the terminal may determine the first value as the maximum number of PDSCHs that can be scheduled in one slot. If the 2-bit is '01', the terminal may determine the second value as the maximum number of PDSCHs that can be scheduled in one slot. If the 2-bit is '10', the terminal may determine the third value as the maximum number of PDSCHs that can be scheduled in one slot. If the 2-bit is '11', the terminal may determine the fourth value as the maximum number of PDSCHs that can be scheduled in one slot. Here, the first value, the second value, the third value, and the fourth value may be 1, 2, 4, and 7, respectively. As another example, the base station may set values ​​corresponding to the first value, the second value, the third value, and the fourth value to the terminal.

[0437] In a second method, a DCI that does not schedule PDSCHs may include a maximum number of PDSCHs that can be processed in one slot. A terminal may transmit HARQ-ACK information for the DCI to a base station, and after a certain point in time following the transmission, the terminal may generate a HARQ-ACK codebook based on the maximum number of PDSCHs that can be processed in one slot included in the DCI. Until the certain point in time, the maximum number of PDSCHs that can be processed in one slot included in the DCI may not be applied. Here, the certain point in time may be the first slot after a certain time (for example, 3 ms) from the symbols or slots that transmitted the HARQ-ACK information for the DCI.

[0438] According to one embodiment of the present disclosure, a terminal can reduce the size of a HARQ-ACK codebook according to its capabilities. The terminal can reduce the size of the codebook based on a Time Domain Resource Assignment (TDRA) table and a TDD configuration.

[0439] A TDD configuration includes the types of symbols set by a base station to a terminal via a System Information Block (SIB) or RRC signal. The symbols can be set to one of the following types: downlink symbols, uplink symbols, and flexible symbols. Downlink symbols are symbols that a terminal can receive on the downlink, but cannot transmit on the uplink. Uplink symbols are symbols that a terminal can transmit on the uplink, but cannot receive on the downlink. Flexible symbols are symbols that a terminal can receive on the downlink or transmit on the uplink.

[0440] The terminal can determine whether to include HARQ-ACK bits in the HARQ-ACK codebook based on the symbol types of the slots in which the terminal's HARQ-ACK bits must be transmitted. For example, if all slots in which HARQ-ACK bits must be transmitted are configured as uplink symbols, the terminal cannot receive the PDSCH in those slots. Therefore, the terminal can exclude the HARQ-ACK bits for those slots from the HARQ-ACK codebook.

[0441] A terminal can determine whether to include HARQ-ACK bits in a HARQ-ACK codebook based on the symbol types of slots in which the terminal's HARQ-ACK bits must be transmitted and the TDRA table settings. Here, the TDRA table can include one or more SLIVs (starting and length indication values) indicating symbols that the terminal can receive as PDSCH in the slot. The terminal can determine whether each SLIV in the TDRA table overlaps with an uplink symbol. If all SLIVs overlap with an uplink symbol, the terminal cannot schedule a PDSCH in the slot. Therefore, the terminal can exclude HARQ-ACK bits for the slot from the HARQ-ACK codebook.

[0442] A terminal configured to use a HARQ-ACK codebook according to terminal capabilities may change the method of including HARQ-ACK bits in slots of the HARQ-ACK codebook based on the TDRA table configuration. The method of including HARQ-ACK bits in the terminal may be selected from at least one of the following.

[0443] - The first method is, according to the second embodiment of the present disclosure, that the terminal includes HARQ-ACK bits for N PDSCH occasions in a slot. Here, N is the maximum number of PDSCHs that the terminal can process in one slot. Therefore, the terminal can include N HARQ-ACK bits for one slot. (Here, it is assumed that one PDSCH occasion corresponds to one HARQ-ACK bit. If one PDSCH occasion corresponds to multiple HARQ-ACK bits, other HARQ-ACK bits can be used instead of N HARQ-ACK bits.)

[0444] - The second method is that the terminal includes HARQ-ACK bits of a slot based on the SLIVs in the TDRA table, as in the Type-1 HARQ-ACK codebook. More specifically, the terminal groups the SLIV ending at the temporally earliest symbol among the SLIVs in the TDRA table and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the TDRA table. For the remaining SLIVs, the terminal continues to group the SLIV ending at the temporally earliest symbol and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the TDRA table. This can continue until there are no SLIVs in the TDRA table. For reference, among the SLIVs included in the TDRA table, the SLIVs overlapping with uplink symbols can be excluded from the TDRA table first.

[0445] For each slot, the terminal may include HARQ-ACK bits by selecting one of the first and second methods. For example, if one of the first and second methods determines a lower number of HARQ-ACK bits in a slot, the terminal may generate HARQ-ACK bits for the slot using the one of the methods.

[0446] FIG. 15 illustrates a flowchart for generating a HARQ-ACK codebook according to terminal capabilities according to one embodiment of the present disclosure.

[0447] In the first step (1500), the terminal can receive K1 value setting information and the maximum number of PDSCHs (N) that can be processed in one slot from the base station. Here, if the terminal does not receive the maximum number of PDSCHs that can be processed in one slot from the base station, the terminal can assume the maximum number of PDSCHs that can be processed in one slot determined according to the terminal's capabilities.

[0448] In the second step (1510), the terminal can determine slots corresponding to the configured K1 value and generate N PDSCH occasions per slot. Then, the terminal can generate a HARQ-ACK bit corresponding to each generated PDSCH occasion. The slot corresponding to the configured K1 value (k1) can be determined as slot n-k1 if the index of the slot in which the HARQ-ACK is transmitted is slot n.

[0449] In the third step (1520), the terminal can determine a PDSCH occasion corresponding to a PDSCH received in a slot corresponding to the configured K1 value. For the above correspondence, the received PDSCH may be assigned an index, and there may be a PDSCH occasion corresponding to each index. Here, the index may be one of the values ​​0, 1, ..., N-1.

[0450] In the fourth step (1530), the terminal may include HARQ-ACK information (ACK or NACK) of the received PDSCH in the HARQ-ACK bit of the determined PDSCH occasion. If the PDSCH corresponding to the PDSCH occasion is not received, the terminal may set the HARQ-ACK information of the PDSCH occasion to 0.

[0451] In step 5 (1540), the terminal may transmit a HARQ-ACK codebook including HARQ-ACK bits for the generated PDSCH occasions to the base station. This may be transmitted on PUCCH or PUSCH.

[0452] [Example 3: Compact Type-1 HARQ-ACK Codebook Method]

[0453] To reduce the size of the Type-1 HARQ-ACK codebook, the base station may set up a virtual TDRA table for determining the number of HARQ-ACK bits for the terminal. The virtual TDRA table may include SLIVs. The virtual TDRA table is set up for the purpose of determining the number of HARQ-ACK bits of the Type-1 HARQ-ACK codebook and may be different from the TDRA table used for actual scheduling.

[0454] For reference, the above virtual TDRA table may only include some of the SLIVs of the TDRA table used for actual scheduling. That is, the SLIV included in the virtual TDRA table is one of the SLIVs of the TDRA table used for actual scheduling. Therefore, the base station can set the SLIVs included in the virtual TDRA table by setting the index of the actual TDRA table to the terminal.

[0455] The terminal can determine the number of HARQ-ACK bits for a slot based on the SLIVs of the virtual TDRA table. More specifically, the terminal groups the SLIV ending at the temporally earliest symbol among the SLIVs in the virtual TDRA table and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the virtual TDRA table. For the remaining SLIVs, the terminal continues to group the SLIV ending at the temporally earliest symbol and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the virtual TDRA table. This can continue until there are no SLIVs in the TDRA table. For reference, among the SLIVs included in the virtual TDRA table, the SLIVs overlapping with uplink symbols can be first excluded from the TDRA table.

[0456] The terminal can determine the correspondence between the SLIVs of the TDRA table to be used for actual scheduling and the HARQ-ACK bits. For example, the terminal can select the earliest (the earliest ending symbol) SLIV among the SLIVs of the virtual TDRA table that overlap with the SLIV of the TDRA table to be used for actual scheduling (hereinafter referred to as the actual SLIV), and determine the HARQ-ACK bit corresponding to the selected SLIV as the bit that transmits the HARQ-ACK information of the PDSCH scheduled with the actual SLIV.

[0457] For reference, when configuring a virtual TDRA table for a terminal, the base station can configure the SLIVs in the virtual TDRA table to not overlap each other within the symbol. With this configuration, the terminal may not perform the operation of determining and removing overlapping SLIVs when acquiring or calculating HARQ-ACK bits based on the virtual TDRA table. In other words, the implementation complexity of the terminal can be reduced.

[0458] For reference, when a base station sets a virtual TDRA table for a terminal, the SLIVs of the virtual TDRA table can be set to include all symbols of a slot. That is, each symbol of a slot can overlap with at least one SLIV.

[0459] A terminal configured to use a Type-1 HARQ-ACK codebook can change the method of including HARQ-ACK bits in a slot of the HARQ-ACK codebook based on the maximum number of PDSCHs that can be processed in one slot. The method of including HARQ-ACK bits in the terminal can be selected from at least one of the following.

[0460] - The first method is, according to the second embodiment of the present disclosure, that the terminal includes HARQ-ACK bits for N PDSCH occasions in a slot. Here, N is the maximum number of PDSCHs that the terminal can process in one slot. Therefore, the terminal can include N HARQ-ACK bits for one slot. (Here, it is assumed that one PDSCH occasion corresponds to one HARQ-ACK bit. If one PDSCH occasion corresponds to multiple HARQ-ACK bits, other HARQ-ACK bits can be used instead of N HARQ-ACK bits.)

[0461] - The second method is that the terminal includes HARQ-ACK bits of a slot based on the SLIVs in the TDRA table, as in the Type-1 HARQ-ACK codebook. More specifically, the terminal groups the SLIV ending at the temporally earliest symbol among the SLIVs in the TDRA table and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the TDRA table. For the remaining SLIVs, the terminal continues to group the SLIV ending at the temporally earliest symbol and the SLIVs overlapping with the SLIVs and allocates one HARQ-ACK bit. Then, the terminal excludes the SLIVs from the TDRA table. This can continue until there are no SLIVs in the TDRA table. For reference, among the SLIVs included in the TDRA table, the SLIVs overlapping with uplink symbols can be excluded from the TDRA table first.

[0462] For each slot, the terminal may include HARQ-ACK bits in the HARQ-ACK codebook by selecting one of the first and second methods. For example, if one of the first and second methods determines a lower number of HARQ-ACK bits in a slot, the terminal may generate HARQ-ACK bits for the corresponding slot using the one of the methods.

[0463] [Example 4: Method for Determining HARQ-ACK Codebook Type]

[0464] A terminal can support more than one HARQ-ACK codebook design. For example, the terminal can simultaneously generate the following two HARQ-ACK codebooks.

[0465] - HARQ-ACK codebook according to terminal capability with the first HARQ-ACK codebook (second embodiment)

[0466] - Type-3 HARQ-ACK codebook as the second HARQ-ACK codebook

[0467] For reference, the above two HARQ-ACK codebooks are only examples, and the embodiments of the present disclosure can be applied to other HARQ-ACK codebooks. In addition, for convenience of explanation, the description is based on two HARQ-ACK codebooks, but the embodiments of the present disclosure can be applied to two or more HARQ-ACK codebooks (for example, the same can be applied to three HARQ-ACK codebooks).

[0468] Type-3 HARQ-ACK codebook (or One-shot codebook) is a method in which the UE reports all HARQ-ACK information for all serving cells and HARQ process numbers, number of TBs per HARQ process, and number of CBGs per TB. For example, if the UE has two serving cells, 16 HARQ processes per serving cell, one TB per HARQ process, and two CBGs per TB, the UE reports a total of 64 (=2 * 16 * 1 * 2) HARQ-ACK information bits.

[0469] A Type-3 HARQ-ACK codebook can list HARQ-ACK information bits in a sequential order. The sequential order is as follows.

[0470] - Can be sorted in ascending order of the serving cell index

[0471] - Within the same serving cell, HARQ processes can be sorted in ascending order.

[0472] - When multiple TBs are included in the same HARQ process (i.e., in the case of 2-TB transmission), the HARQ-ACK information of the first TB may be aligned in a position ahead of the HARQ-ACK information of the second TB.

[0473] - When the same TB includes multiple CBGs (i.e., in the case of CBG-based PDSCH transmission), they can be sorted in ascending order of the CBG indices.

[0474] According to one embodiment of the present disclosure, the terminal may determine the length of each HARQ-ACK codebook. For example, in the case of the first HARQ-ACK codebook, the length of the HARQ-ACK codebook may be {the number of slots corresponding to the K1 value * the maximum number of PDSCHs that can be processed in one slot}. Note that the number of slots corresponding to the K1 value may vary depending on the TDD configuration information. In the case of the second HARQ-ACK codebook, the length of the HARQ-ACK codebook may be equal to the number of configured HARQ process numbers.

[0475] The terminal can compare the lengths of the two HARQ-ACK codebooks. If the length of the first HARQ-ACK codebook is smaller than the length of the second HARQ-ACK codebook, the terminal can select the first HARQ-ACK codebook. Conversely, if the length of the second HARQ-ACK codebook is smaller than the length of the first HARQ-ACK codebook, the terminal can select the second HARQ-ACK codebook. That is, if the terminal can generate two or more HARQ-ACK codebooks, the terminal can select one of the HARQ-ACK codebooks based on the length of the HARQ-ACK codebook.

[0476] The terminal can transmit the selected HARQ-ACK codebook to the base station. At this time, the HARQ-ACK codebook can be transmitted via PUCCH or PUSCH.

[0477] By selecting a shorter HARQ-ACK codebook and transmitting it to the base station, the terminal can reduce uplink resource overhead. Note that the base station knows the length of the HARQ-ACK codebook the terminal will generate. Therefore, the base station can know in advance which HARQ-ACK codebook the terminal will transmit.

[0478] According to one embodiment of the present disclosure, the type of HARQ-ACK codebook to be used by a terminal may be indicated through DCI. More specifically, the terminal may be configured with the type of available HARQ-ACK codebook from the base station. In addition, the terminal may be configured with the type of HARQ-ACK codebook to be used from the DCI. For example, if the terminal is configured with a first HARQ-ACK codebook and a second HARQ-ACK codebook from the base station, the DCI may include a field for selecting one of the two codebooks. Based on the field, the terminal may generate a HARQ-ACK codebook. For reference, the DCI here may be a DCI format capable of scheduling a PDSCH.

[0479] FIG. 16 is a flowchart for selecting a HARQ-ACK codebook type according to one embodiment of the present disclosure.

[0480] In the first step (1600), the terminal can calculate the number of HARQ-ACK bits included in the HARQ-ACK codebook according to the first method or the first HARQ-ACK codebook setting. In addition, the terminal can calculate the number of HARQ-ACK bits included in the HARQ-ACK codebook according to the second method or the second HARQ-ACK codebook setting.

[0481] In the second step (1610), the terminal can compare the number of HARQ-ACK bits determined according to two methods or two HARQ-ACK codebook settings. The terminal can select a method or HARQ-ACK codebook setting that provides a smaller number of HARQ-ACK bits determined according to two methods or two HARQ-ACK codebook settings.

[0482] In the third step (1620), the terminal can generate a HARQ-ACK codebook according to the selected method or the selected HARQ-ACK codebook setting and transmit it to the base station.

[0483] FIG. 17 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0484] Referring to FIG. 17, the terminal may include a transceiver, which refers to a terminal receiving unit (1700) and a terminal transmitting unit (1710), a memory (not shown), and a terminal processing unit (1705, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver units (1700, 1710), the memory, and the terminal processing unit (1705) 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.

[0485] A transceiver unit can transmit and receive signals with a base station or other terminals. 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.

[0486] 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.

[0487] 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.

[0488] Additionally, the processor can control a series of processes to enable the terminal to operate according to the aforementioned embodiments. For example, the processor can receive DCI consisting of two layers and control components of the terminal to simultaneously receive multiple PDSCHs. There may be multiple processors, and the processors can perform terminal component control operations by executing programs stored in memory.

[0489] FIG. 18 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0490] Referring to FIG. 18, the base station may include a transceiver, which refers to a base station receiver (1800) and a base station transmitter (1810), a memory (not shown), and a base station processor (1805, or a base station control unit or processor). Depending on the communication method of the base station described above, the transceiver (1800, 1810), the memory, and the base station processor (1805) 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.

[0491] The transceiver can transmit and receive signals with a terminal or another base station. The signals may include control information and data. To this end, the transceiver 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 merely one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0492] 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.

[0493] 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.

[0494] The processor can control a series of processes to enable the base station to operate according to the embodiments of the present disclosure described above. For example, the processor can configure two layers of DCIs containing allocation information for multiple PDSCHs and control each component of the base station to transmit them. There may be multiple processors, and the processors can perform component control operations of the base station by executing programs stored in memory.

[0495] The present disclosure proposes a method for designing a HARQ-ACK codebook according to the UE capability.

[0496] A terminal can report to a base station the maximum number of PDSCHs it can receive (process) per slot. The terminal can generate a HARQ-ACK codebook based on the maximum number of PDSCHs.

[0497] The HARQ-ACK codebook transmitted in slot n can include as many HARQ-ACK bits as the number of configured K1 values ​​* the maximum number of PDSCHs. Here, the b-th bit represents the HARQ-ACK information of the ith PDSCH received in slot n-K1,k. Here, k=floor(n / number of configured K1 values), i=bk*number of configured K1 values, and K1,k is the k-th K1 value among the configured K1 values.

[0498] If the maximum number of PDSCHs that a terminal can receive (process) per slot is greater than 2 (2, 4, or 7), the terminal must determine the order of the PDSCHs received within the slot (the i-th PDSCH). For this purpose, the following methods may be considered.

[0499] The DCI format for scheduling PDSCHs can indicate the order of PDSCHs received within a slot. For example, if '0' is indicated, it can be determined to be the 0th PDSCH.

[0500] The order of the PDSCH can be determined based on the time-domain allocation information or frequency-domain allocation information of the PDSCH. For example, if the start symbol / RB of the received PDSCH is a specific index, the terminal can determine the order of the PDSCH based on the specific index. Alternatively, if the number of symbols / RBs included in the received PDSCH is a specific number, the terminal can determine the order of the PDSCH based on the specific number.

[0501] 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.

[0502] 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.

[0503] 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.

[0504] 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.

[0505] 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.

[0506] 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.

[0507] 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.

[0508] 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.

[0509] 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.

[0510] 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. A method performed by a terminal in a wireless communication system, the method comprising: A step of transmitting capability information about the maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot to a base station; A step of receiving, from the base station, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook and second information regarding a maximum number of PDSCHs scheduled in one slot; A step of determining a reception slot of at least one PDSCH based on the first information; A step of generating a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled for each reception slot of at least one PDSCH determined based on the second information, The HARQ-ACK information is configured for each reception slot of at least one of the determined PDSCHs; and A method comprising the step of transmitting the generated HARQ-ACK codebook to a base station 2. In paragraph 1, The PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information includes a PDSCH scheduled by downlink control information (DCI). For each PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information, an order within the reception slot of the PDSCH is assigned. A method in which the position of the HARQ-ACK information within the HARQ-ACK codebook is determined according to the order within the reception slot of the PDSCH.

3. In paragraph 2, If the DCI includes a field for indicating an order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH, the order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH is assigned by the field, A method wherein, if the DCI does not include a field for indicating an order of PDSCHs scheduled by the DCI within a reception slot of the PDSCHs, the order of PDSCH opportunities scheduled by the DCI within a reception slot of the PDSCHs is set to the first.

4. In paragraph 1, A method in which the maximum number of PDSCHs that the terminal can receive in one slot based on the number of physical resource blocks (PRBs) allocated to the PDSCH is determined as one of the different maximum numbers, wherein the maximum number of PDSCHs that the terminal can receive in one slot, which is included in the capability information, is determined as one of the different maximum numbers.

5. In the first paragraph, the method, Further comprising a step of receiving information for changing the maximum number of PDSCH opportunities scheduled in the one slot set based on the second information from the base station, A method in which information for changing the above maximum number is configured based on DCI, MAC (medium access control)-CE (control element), or RRC (radio resource control).

6. A method performed by a base station in a wireless communication system, the method comprising: A step of receiving, from a terminal, capability information on the maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot; A step of transmitting, to the terminal, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook and second information about a maximum number of PDSCH opportunities scheduled in one slot; and A step of receiving, from the terminal, a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled for each of at least one PDSCH reception slots determined based on the first information, based on the second information, A method wherein the above HARQ-ACK information is configured for each reception slot of at least one PDSCH determined.

7. In paragraph 6, The PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information includes a PDSCH scheduled by downlink control information (DCI). For each PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information, an order within the reception slot of the PDSCH is assigned. A method in which the position of the HARQ-ACK information within the HARQ-ACK codebook is determined according to the order within the reception slot of the PDSCH.

8. In paragraph 7, If the DCI includes a field for indicating an order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH, the order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH is assigned by the field, A method wherein, if the DCI does not include a field for indicating an order of PDSCHs scheduled by the DCI within a reception slot of the PDSCHs, the order of PDSCH opportunities scheduled by the DCI within a reception slot of the PDSCHs is set to the first.

9. In paragraph 6, A method in which the maximum number of PDSCHs that the terminal can receive in one slot based on the number of physical resource blocks (PRBs) allocated to the PDSCH is determined as one of the different maximum numbers, wherein the maximum number of PDSCHs that the terminal can receive in one slot, which is included in the capability information, is determined as one of the different maximum numbers.

10. In paragraph 6, the method, Further comprising a step of transmitting information for changing the maximum number of PDSCH opportunities scheduled in the one slot set based on the second information to the terminal, A method in which information for changing the above maximum number is configured based on DCI, MAC (medium access control)-CE (control element), or RRC (radio resource control).

11. In a wireless communication system, the terminal comprises: transceiver; and Including a controller connected to the above transceiver, The above controller: Transmits capability information about the maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot to the base station, Receive, from the base station, first information including at least one slot offset value between each reception slot of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook, and configuration information including second information about the maximum number of PDSCHs scheduled in one slot, Determine a reception slot of at least one PDSCH based on the first information above, Generating a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled for each reception slot of at least one PDSCH determined based on the second information, The above HARQ-ACK information is configured for each reception slot of at least one of the determined PDSCHs, A terminal configured to transmit the generated HARQ-ACK codebook to a base station.

12. In paragraph 11, The PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information includes a PDSCH scheduled by downlink control information (DCI). For each PDSCH scheduled in the reception slot of the PDSCH corresponding to the above HARQ-ACK information, an order within the reception slot of the PDSCH is assigned. A terminal, wherein the position of the HARQ-ACK information within the HARQ-ACK codebook is determined according to the order within the reception slot of the PDSCH.

13. In paragraph 12, If the DCI includes a field for indicating an order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH, the order of the PDSCH scheduled by the DCI within a reception slot of the PDSCH is assigned by the field, If the DCI does not include a field for indicating an order of PDSCH scheduled by the DCI within a reception slot of the PDSCH, the order of PDSCH opportunities scheduled by the DCI within a reception slot of the PDSCH is set to the first, the terminal.

14. In paragraph 11, A terminal wherein the maximum number of PDSCHs that the terminal can receive in one slot based on the number of physical resource blocks (PRBs) allocated to the PDSCH is determined as one of the different maximum numbers, and the maximum number of PDSCHs that the terminal can receive in one slot, which is included in the capability information, is determined as one of the different maximum numbers.

15. In a wireless communication system, at a base station, the base station, transceiver; and Including a controller connected to the above transceiver, The above controller: Receive capability information from a terminal about the maximum number of physical downlink shared channels (PDSCHs) that the terminal can receive in one slot, Transmitting, to the terminal, configuration information including first information including at least one slot offset value between each reception slot of at least one PDSCH and a transmission slot of a hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook and second information about the maximum number of PDSCH opportunities scheduled in one slot, The terminal is configured to receive, from the terminal, a HARQ-ACK codebook including a number of HARQ-ACK information corresponding to the maximum number of PDSCHs that can be scheduled for each of at least one PDSCH reception slots determined based on the first information, based on the second information. A base station, wherein the above HARQ-ACK information is configured for each reception slot of at least one PDSCH determined.

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