Method and device for transmitting / receiving control and data information in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method performed by a base station in a wireless communication system, according to various embodiments of the present disclosure, may comprise the steps of: receiving, from a user equipment and through a physical random access channel (PRACH) or message 3, capability information with respect to repetitive transmission of the user equipment; identifying a repetitive transmission value on the basis of the capability information and the distance between the user equipment and the base station; and transmitting information related to the repetitive transmission value to the user equipment.

Description

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

[0001] The present disclosure relates to a wireless communication system, and more specifically, to the operation of a terminal and a base station in a satellite communication system. Specifically, the present disclosure relates to a method and device for transmitting and receiving control and data information in a satellite communication system.

[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 (THz) band (for example, 3 THz band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

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

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

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

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

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

[0008] As mentioned above, the advancement of wireless communication systems can provide a variety of services. Therefore, a method for seamlessly providing these services is needed.

[0009] The present invention relates to wireless communication systems, and more specifically, to the operation of terminals and base stations in satellite communication systems. According to various embodiments of the present disclosure, an apparatus and method capable of effectively providing services in a wireless communication system are provided.

[0010] According to various embodiments of the present disclosure, in a wireless communication system, a method performed by a base station may include the steps of receiving capability information for repeated transmission of a user equipment (UE) through a physical random access channel (PRACH) or message 3, identifying a value of repeated transmission based on the capability information and a distance between the UE and the base station, and transmitting information about the value of repeated transmission to the UE.

[0011] Through embodiments of the present disclosure, a device and method capable of effectively providing a service in a wireless communication system are provided.

[0012] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] FIG. 6 is a diagram illustrating a case in which a terminal can have multiple PDCCH monitoring positions within a slot through Span in a wireless communication system according to one embodiment of the present disclosure.

[0019] FIG. 7 is a diagram illustrating an example of base station beam allocation according to TCI state settings in a wireless communication system according to one embodiment of the present disclosure.

[0020] FIG. 8 is a diagram illustrating an example of a TCI state allocation method for a PDCCH in a wireless communication system according to one embodiment of the present disclosure.

[0021] FIG. 9 is a diagram illustrating a TCI indication MAC CE signaling structure for PDCCH DMRS in a wireless communication system according to one embodiment of the present disclosure.

[0022] FIG. 10 is a diagram illustrating an example of a control resource set and a beam setting of a search space in a wireless communication system according to one embodiment of the present disclosure.

[0023] FIG. 11 is a diagram for explaining a method for a base station and a terminal to transmit and receive data in consideration of a downlink data channel and rate matching resources in a wireless communication system according to one embodiment of the present disclosure.

[0024] FIG. 12 is a diagram for explaining a method for selecting a set of control resources that can be received by a terminal in consideration of priority when receiving a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0025] FIG. 13 is a diagram illustrating an example of an aperiodic CSI reporting method according to one embodiment of the present disclosure.

[0026] FIG. 14 is a diagram illustrating an example of PUSCH repetition transmission type B in a wireless communication system according to one embodiment of the present disclosure.

[0027] FIG. 15 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation in a wireless communication system according to one embodiment of the present disclosure.

[0028] FIG. 16 is a diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to one embodiment of the present disclosure.

[0029] FIG. 17 is a diagram illustrating an example of configuring downlink control information (DCI) for cooperative communication in a wireless communication system according to one embodiment of the present disclosure.

[0030] Figure 18 illustrates a procedure for a base station to control the transmission power of a terminal in a cellular system.

[0031] FIG. 19 is a diagram illustrating a process for generating a Type-1 (semi-static) HARQ-ACK codebook by a terminal according to one embodiment of the present disclosure.

[0032] FIG. 20 is a diagram illustrating a process for generating a Type-2 (dynamic) HARQ-ACK codebook by a terminal according to one embodiment of the present disclosure.

[0033] FIG. 21 is a diagram illustrating a procedure for transmitting and receiving data between a terminal and a base station to perform an initial connection according to one embodiment.

[0034] FIG. 22 is a diagram illustrating the Earth orbital period of a communication satellite according to the altitude or height of the satellite according to one embodiment of the present disclosure.

[0035] FIG. 23 illustrates a signal flow for performing an initial connection between a terminal and a base station according to one embodiment of the present disclosure.

[0036] FIG. 24 illustrates a flow of operations for a terminal to repeatedly transmit and receive signals for channels according to one embodiment of the present disclosure.

[0037] FIG. 25 illustrates a situation in which a DCI scheduling message 2 is repeatedly transmitted after transmission of a physical random access channel (PRACH) according to one embodiment of the present disclosure.

[0038] FIG. 26 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0039] FIG. 27 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0040] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0041] 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 avoid obscuring the gist of the present disclosure by omitting unnecessary explanations and to convey the gist more clearly.

[0042] 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.

[0043] 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 may refer to 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 may be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout the specification.

[0044] Hereinafter, a base station is an entity that performs resource allocation of a terminal, and may include at least one of a satellite, a gateway, a ground station, 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) may refer to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) may refer to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although 5G or a next-generation system may be described as an example below, embodiments of the present disclosure may also be applied to other communication systems having a similar technical background or channel type. For example, this may include LTE or LTE-A mobile communication and mobile communication technologies developed after 5G, and 5G below may also be a concept that includes 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 skilled in the art, without significantly departing from the scope of the present disclosure. The contents of the present disclosure are applicable to FDD and TDD systems.

[0045] 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).

[0046] 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.

[0047] Here, the term '~ unit' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and '~ unit' can perform certain roles. However, '~ unit' is not limited to software or hardware. '~ unit' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Therefore, as an example, '~ unit' may include 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 '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~parts' may include one or more processors.

[0048] 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.

[0049] As a representative example of the above-mentioned broadband wireless communication system, the LTE system adopts the OFDM (Orthogonal Frequency Division Multiplexing) method in the downlink (DL) and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method in the uplink (UL). The uplink refers to a wireless link in which a user equipment (UE) or mobile station (MS) transmits data or control signals to a base station (eNode B or base station (BS)), and the downlink can refer to a wireless link in which a base station transmits data or control signals to a UE. The multiple access method described above typically allocates and operates 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, thereby distinguishing the data or control information of each user.

[0050] As a future communication system beyond LTE, 5G communication systems must be able to freely reflect the diverse needs of users and service providers. Therefore, services that simultaneously satisfy these requirements must be supported. Services being considered for 5G communication systems include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC).

[0051] eMBB may aim to provide data rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB should 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, may be required. Furthermore, while LTE transmits signals using a maximum 20 MHz transmission bandwidth in the 2 GHz band, 5G communication systems can meet the data rates required by 5G communication systems by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher 6 GHz bands.

[0052] At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide the IoT, mMTC requires supporting large-scale terminal connections within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. The IoT requires the ability to support a large number of terminals (e.g., 1,000,000 terminals / km2) within a cell, as it provides communication capabilities through the attachment of various sensors and devices. Furthermore, due to the nature of the service, terminals supporting mMTC are likely to be located in shadow areas, such as basements, beyond cell coverage. This may require broader coverage compared to other services provided by 5G communication systems. Terminals supporting mMTC must be inexpensive, and since frequent battery replacement is unlikely, they may require extremely long battery lifespans, such as 10 to 15 years.

[0053] 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 10-5 or lower. Therefore, for URLLC-enabled services, 5G systems must provide shorter transmit time intervals (TTIs) than other services, while simultaneously allocating extensive resources in the frequency band to ensure communication link reliability.

[0054] 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.

[0055] [NR time-frequency resources]

[0056] Below, the frame structure of the 5G system is described in more detail with reference to drawings.

[0057] 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.

[0058] 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) in the time axis and 1 subcarrier (103) in the frequency axis. In the frequency domain (For example, 12) consecutive REs can form one resource block (RB) (104).

[0059] 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.

[0060] FIG. 2 illustrates an example of a structure of a frame (200), a subframe (201), and a 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 μ = 0 (204) and μ = 1 (205) as the subcarrier spacing setting value 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.

[0061]

[0062] [Bandwidth Part (BWP)]

[0063] Next, the bandwidth part (BWP) setting in the 5G communication system will be explained in detail with reference to the drawing.

[0064] 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.

[0065] 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 the following information for each bandwidth portion.

[0066]

[0067] Of course, it is not limited to the above-described examples, and in addition to the above-described configuration information, various parameters related to the bandwidth portion can be set for the terminal. The above-described 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).

[0068] 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 where a PDCCH for receiving system information (which may correspond to Remaining System Information (RMSI) or System Information Block 1 (SIB1)) required for initial access can be transmitted through the MIB during the initial access phase. 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.

[0069] The bandwidth settings supported by 5G can be used for various purposes.

[0070] In some embodiments, when the bandwidth supported by a terminal is smaller than the system bandwidth, this can be supported through bandwidth-part configuration. For example, the base station can configure the bandwidth-part frequency location (configuration information 2) for the terminal, allowing the terminal to transmit and receive data at a specific frequency location within the system bandwidth.

[0071] 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, two bandwidth segments may be configured with subcarrier spacings of 15 kHz and 30 kHz, respectively. The different bandwidth segments may be frequency-division multiplexed, 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.

[0072] Furthermore, in some embodiments, the base station may configure bandwidth portions with different bandwidth sizes for the terminal for the purpose of reducing power consumption of the terminal. For example, if the terminal supports a very large bandwidth, for example, 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 situation where there is no traffic may be very inefficient in terms of power consumption. To reduce power consumption of the terminal, the base station may configure a bandwidth portion with a relatively small bandwidth, for example, 20 MHz, for the terminal. In a situation where there is no traffic, 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.

[0073] In the method for setting the bandwidth part described above, terminals before RRC connection 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 DCI (Downlink Control Information) that schedules a SIB (System Information Block) can be transmitted from the MIB of the PBCH (Physical Broadcast Channel). The bandwidth of the control region set by the MIB can be regarded as the initial bandwidth part, and the terminal can receive the PDSCH (Physical Downlink Shared Channel) on which the SIB is transmitted through the set 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.

[0074] [Bandwidth Part (BWP) Change]

[0075] According to one embodiment, when one or more bandwidth part values ​​are set for a terminal, the base station may instruct the terminal to change (or switch, transition) the bandwidth part value using the bandwidth part indicator field in the DCI. For example, in FIG. 3, when the currently activated bandwidth part of the terminal is bandwidth part #1 (301), the base station may instruct the terminal to bandwidth part #2 (302) using the bandwidth part indicator in the DCI, and the terminal may perform a bandwidth part change to bandwidth part #2 (302) indicated by the bandwidth part indicator in the received DCI.

[0076] In one embodiment, since the DCI-based bandwidth part change as described above can be indicated by the DCI scheduling the PDSCH or PUSCH, when the terminal receives a bandwidth part change request, it must be able to smoothly 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 follows.

[0077]

[0078] In one embodiment, the requirement for bandwidth part change delay time may support Type 1 or Type 2 depending on the capability of the terminal. The terminal may report to the base station the type of bandwidth part delay time that it can support.

[0079] According to one embodiment, when a terminal receives a DCI including a bandwidth portion change indicator in slot n, in accordance with the requirement for the bandwidth portion change delay time described above, the terminal may complete the change to a new bandwidth portion indicated by the bandwidth portion change indicator at a time no later than slot n + TBWP, and may perform transmission and reception for a data channel scheduled by the corresponding DCI in the changed new bandwidth portion. When the base station intends to schedule a data channel in the new bandwidth portion, the base station may determine the time domain resource allocation for the data channel by considering the bandwidth portion change delay time (TBWP) of the terminal. That is, when the base station schedules a data channel in the new bandwidth portion, the data channel may be scheduled after the bandwidth portion change delay time in the method of determining the time domain resource allocation for the data channel. Accordingly, the terminal may not expect that the DCI indicating the bandwidth portion change indicates a slot offset (K0 or K2) value that is smaller than the bandwidth portion change delay time (TBWP).

[0080] In one embodiment, if a terminal receives a DCI (e.g., DCI format 1_1 or 0_1) indicating a bandwidth part change, the terminal may not perform any transmission or reception during a time period corresponding to a time interval from the third symbol of a slot in which a PDCCH including the DCI is received to the start point of a slot indicated by a slot offset (K0 or K2) value indicated by a time domain resource allocation indicator field in the DCI. For example, if a terminal receives a DCI indicating a bandwidth part 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).

[0081] [SS / PBCH block]

[0082] Next, we will explain the SS (Synchronization Signal) / PBCH (physical broadcase channel) block in 5G.

[0083] In one embodiment, an SS / PBCH block may refer to a physical layer channel block composed of a PSS (Primary SS), SSS (Secondary SS), and PBCH. Specifically, the block is as follows.

[0084] - PSS: A signal that serves as a reference for downlink time / frequency synchronization and can provide some information about cell ID (identity).

[0085] - SSS: It serves as a reference for downlink time / frequency synchronization and can provide remaining cell ID information not provided by PSS. Additionally, it can serve as a reference signal for PBCH demodulation.

[0086] - PBCH: This channel can provide essential system information required for transmission and reception of data and control channels of a terminal. 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.

[0087] - 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.

[0088] According to one embodiment, the terminal can detect PSS and SSS in the initial access stage, and decode PBCH. The terminal can obtain MIB from PBCH and 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 a 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.

[0089] [PDCCH: DCI related]

[0090] Next, we will specifically explain downlink control information (DCI) in the 5G system.

[0091] 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.

[0092] According to one embodiment, DCI may be transmitted over a Physical Downlink Control Channel (PDCCH) after going through a channel coding and modulation process. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC may be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs may 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. Upon receiving a DCI message transmitted on the PDCCH, the UE verifies the CRC using the assigned RNTI. If the CRC verification result is correct, the UE can determine that the message has been transmitted to the UE.

[0093] 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).

[0094] In one embodiment, DCI format 0_0 may be used as a fallback DCI for scheduling PUSCH, wherein the CRC may be scrambled with C-RNTI. DCI format 0_0 with the CRC scrambled with C-RNTI may include, for example, the following information.

[0095]

[0096] In one embodiment, DCI format 0_1 ​​may be used as a fallback DCI for scheduling PUSCH, wherein the CRC may be scrambled with C-RNTI. DCI format 0_1 ​​with the CRC scrambled with C-RNTI may include, for example, the following information.

[0097]

[0098] In one embodiment, DCI format 1_0 may be used as a fallback DCI for scheduling PDSCH, wherein the CRC may be scrambled with C-RNTI. DCI format 1_0 with the CRC scrambled with C-RNTI may include, for example, the following information.

[0099]

[0100] In one embodiment, DCI format 1_1 may be used as a fallback DCI for scheduling PDSCH, wherein the CRC may be scrambled with C-RNTI. DCI format 1_1 with the CRC scrambled with C-RNTI may include, for example, the following information.

[0101]

[0102] [PDCCH: CORESET, REG, CCE, Search Space]

[0103] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0104] FIG. 4 is a diagram illustrating an example of a control region (Control Resource Set, CORESET) in which a downlink control channel is transmitted in a 5G wireless communication system. 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 time axis may be set to one or more OFDM symbols, which may be defined as the control region length (Control Resource Set Duration, 404). Referring to the example illustrated in FIG. 4, Control Region #1 (401) is set to a control region length of two symbols, and Control Region #2 (402) is set to a control region length of one symbol.

[0105] In one embodiment, the control region in the aforementioned 5G may be configured by the base station to the terminal via higher-layer signaling (e.g., system information, Master Information Block (MIB), Radio Resource Control (RRC) signaling). Configuring the control region for the terminal may mean providing information such as the control region identifier, the frequency location of the control region, and the symbol length of the control region. For example, the information may include the following:

[0106]

[0107] According to one embodiment, the tci-StatesPDCCH (simply named TCI (Transmission Configuration Indication) state) configuration information in Table 9 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.

[0108] 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. Specifically, FIG. 5 is a diagram illustrating an example of the basic units of time and frequency resources that constitute a downlink control channel that can be used in 5G.

[0109] According to one embodiment, according to FIG. 5, the basic unit of time and frequency resources constituting the control channel may be referred to as a REG (Resource Element Group) (503), and the REG (503) may be defined as 1 OFDM symbol (501) in the time axis and 1 PRB (Physical Resource Block) (502) in the frequency axis, i.e., 12 subcarriers. The base station may concatenate REGs (503) to configure a downlink control channel allocation unit.

[0110] According to one embodiment, when the basic unit to which a downlink control channel is allocated in 5G is referred to as a Control Channel Element (CCE) (504) as illustrated in FIG. 5, 1 CCE (504) may be composed of multiple REGs (503). Taking the REG (503) illustrated in FIG. 5 as an example, the REG (503) may be composed of 12 REs, and if 1 CCE (504) is composed of 6 REGs (503), 1 CCE (504) may be composed of 72 REs. When a downlink control region is set, the region may be composed of multiple CCEs (504), and a specific downlink control channel may be mapped to one or multiple CCEs (504) and transmitted according to an 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.

[0111] According to one embodiment, 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 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 contain 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.

[0112] In one embodiment, the search space may be classified into a common search space and a UE-specific search space. A certain group of UEs or all UEs may search the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling for system information or paging messages. For example, PDSCH scheduling allocation information for transmitting SIBs, including cell operator information, may 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 may be defined as a set of pre-arranged CCEs. Scheduling allocation information for UE-specific PDSCH or PUSCH may be received by searching the UE-specific search space of the PDCCH. The UE-specific search space may be defined UE-specifically as a function of the UE's identity and various system parameters.

[0113] In one embodiment, in 5G, parameters for a search space for a PDCCH may be configured from a base station to a terminal via higher layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station may configure the number of PDCCH candidates in each aggregation level L, a monitoring period for the search space, a monitoring occasion per symbol within a slot for the search space, a search space type (common search space or terminal-specific search space), a combination of a DCI format and an RNTI to be monitored in the corresponding search space, a control region index to be monitored for the search space, etc. to the terminal. For example, the following information may be included.

[0114]

[0115] According to one embodiment, the base station may configure one or more search space sets for the terminal based on configuration information. According to some embodiments, the base station may configure search space set 1 and search space set 2 for the terminal, and configure the terminal to monitor DCI format A scrambled with X-RNTI in search space set 1 in a common search space, and configure the terminal to monitor DCI format B scrambled with Y-RNTI in search space set 2 in a terminal-specific search space.

[0116] In one embodiment, 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 set as a common search space, and search space set #3 and search space set #4 may be set as terminal-specific search spaces.

[0117] In one embodiment, the following combinations of DCI formats and RNTIs may be monitored in the common search space, although the present invention is not limited to the following examples.

[0118] - 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

[0119] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0120] - - DCI format 2_1 with CRC scrambled by INT-RNTI

[0121] DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0122] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0123] In one embodiment, the following combinations of DCI formats and RNTIs may be monitored in a terminal-specific search space, although the present invention is not limited to the following examples.

[0124] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0125] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0126] In one embodiment, the specified RNTIs may follow the definitions and usages below.

[0127] - C-RNTI (Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0128] - TC-RNTI (Temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes

[0129] - CS-RNTI (Configured Scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0130] - RA-RNTI (Random Access RNTI): Used for PDSCH scheduling in the random access phase.

[0131] - P-RNTI (Paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0132] - SI-RNTI (System Information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0133] - INT-RNTI (Interruption RNTI): Used to indicate whether pucturing is in progress for PDSCH.

[0134] - TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to indicate power control commands for PUSCH.

[0135] - TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to indicate power control commands for PUCCH.

[0136] - TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used to indicate power control commands for SRS.

[0137] According to one embodiment, the specified DCI formats described above may follow the definitions below.

[0138]

[0139] According to one embodiment, in 5G, a 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.

[0140] [Mathematical Formula 1]

[0141]

[0142] - L: Integration level

[0143] - n CI : Carrier Index

[0144] - N CCE,p : Total number of CCEs existing within the control region p

[0145] - : slot index

[0146] - : Number of PDCCH candidates for aggregation level L

[0147] - = 0, ... , -1: PDCCH candidate index of aggregation level L

[0148] - i = 0, ... , L -1

[0149] - =(A p dot )mod D, Y p,-1 =n RNTI ≠0, A p =39827 for pmod3=0, A p =39829 for pmod3=1, A p =39839 for pmod3=2, D=65537

[0150] - n RNTI : Terminal identifier

[0151] The value can be 0 for a common search space.

[0152] 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.

[0153] In one embodiment, in 5G, since multiple search space sets can be set with different parameters (e.g., parameters of Table 10), the set of search space sets monitored by the 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, and can monitor either search space set #1 or search space set #2 in a specific slot.

[0154] [PDCCH: span]

[0155] According to one embodiment, a terminal may perform a terminal capability report for each subcarrier interval when having multiple PDCCH monitoring positions within a slot, and at this time, a concept called Span may be used. A Span refers to consecutive symbols within a slot in which the terminal can monitor a PDCCH, and each PDCCH monitoring position is within one Span. A Span may be expressed as (X, Y), where x refers to the minimum number of symbols that must be spaced between the first symbols of two consecutive Spans, and Y may refer to the number of consecutive symbols in which the PDCCH can be monitored within one Span. In this case, the terminal may monitor the PDCCH in a section from the first symbol of the Span to Y symbols within the Span.

[0156] FIG. 6 is a diagram illustrating a case in which a terminal in a wireless communication system can have multiple PDCCH monitoring positions within a slot through Span.

[0157] In one embodiment, Span can be (X, Y) = (7, 4), (4, 3), (2, 2), and each of these three cases is represented by (600), (605), and (610) in FIG. 6. For example, (600) represents a case where there are two Spans that can be represented by (7, 4) within a slot. The interval between the first symbols of the two Spans is represented by X=7, and the PDCCH monitoring positions can exist within a total of Y=3 symbols from the first symbol of each Span, and search spaces 1 and 2 each exist within Y=3 symbols. As another example, (605) represents a case where there are three Spans that can be represented by (4, 3) within a slot, and the interval between the second and third Spans is represented as X'=5 symbols, which is larger than X=4.

[0158] [PDCCH: Terminal Capability Report]

[0159] According to one embodiment, the slot positions where the above-described common search space and terminal-specific search space are located are indicated by the monitoringSymbolsWitninSlot parameter of Table 13-1, and the symbol positions within the slot are indicated as a bitmap through the monitoringSymbolsWithinSlot parameter of Table 9. Meanwhile, the symbol positions within the slot where the terminal can monitor the search space can be reported to the base station through the following terminal capabilities (UE capabilities).

[0160] - Terminal capability 1 (hereinafter referred to as FG 3-1). This terminal capability may refer to the capability to monitor a monitoring occasion (MO) for a Type 1 and Type 3 common search space or a terminal-specific search space when the MO position is located within the first three symbols of the slot, as shown in Table 11 below. This terminal capability is a mandatory capability that all terminals supporting NR must support, and whether or not this capability is supported is not explicitly reported to the base station.

[0161]

[0162] - Terminal Capability 2 (hereinafter referred to as FG 3-2). This terminal capability can refer to the capability to monitor a common search space or a terminal-specific search space, regardless of the starting symbol position of a monitoring occasion (MO), if there is one within a slot, as shown in Table 12 below. This terminal capability is optional for the terminal, and whether or not it is supported is explicitly reported to the base station.

[0163]

[0164] - Terminal capability 3 (hereinafter referred to as FG 3-5, 3-5a, 3-5b). This terminal capability can indicate the pattern of MOs that the terminal can monitor when there are multiple monitoring positions for a common search space or a terminal-specific search space within a slot, as shown in Table 13 below. The above-described pattern is composed of the start symbol interval X between different MOs and the maximum symbol length Y for an MO. The combination of (X, Y) supported by the terminal can be one or more of {(2, 2), (4, 3), (7, 3)}. This terminal capability can be selectively supported by the terminal (optional), and whether this capability is supported and the above-described combination of (X, Y) are explicitly reported to the base station.

[0165]

[0166]

[0167] In one embodiment, the terminal may report to the base station whether it supports the aforementioned terminal capability 2 and / or terminal capability 3 and related parameters. Based on the reported terminal capabilities, the base station may perform time-domain resource allocation for the common search space and terminal-specific search space. When allocating resources, the base station may ensure that the MO is not positioned in a location where the terminal cannot monitor.

[0168] [QCL, TCI state]

[0169] According to one embodiment, in a wireless communication system, one or more different antenna ports (or one or more channels, signaling, and combinations thereof, but for convenience, they will be referred to as different antenna ports in the following description of the present disclosure) may be associated with each other by a QCL (Quasi co-location) setting as shown in [Table 14] below.

[0170] In one embodiment, the TCI state is intended to announce a QCL relationship between the PDCCH (or PDCCH DMRS) and other RSs or channels, such that a reference antenna port A (reference RS #A) and another target antenna port B (target RS #B) being QCLed may mean that the UE is allowed to apply some or all of the large-scale channel parameters estimated at antenna port A to the channel measurement from antenna port B.

[0171] In some embodiments, QCL may need to relate different parameters depending on the situation, such as 1) time tracking affected by average delay and delay spread, 2) frequency tracking affected by Doppler shift and Doppler spread, 3) radio resource management (RRM) affected by average gain, and 4) beam management (BM) affected by spatial parameters. Accordingly, NR can support four types of QCL relationships, as shown in Table 14 below.

[0172]

[0173] In one embodiment, the spatial RX parameter may collectively refer to some or all of various parameters, such as Angle of arrival (AoA), Power Angular Spectrum (PAS) of AoA, Angle of departure (AoD), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, and spatial channel correlation.

[0174] According to one embodiment, the QCL relationship can be set to the terminal through the RRC parameters TCI-State and QCL-Info as shown in Table 15 below. Referring to Table 15, the base station can set one or more TCI states to the terminal and inform the RS referencing the ID of the TCI state, i.e., up to two QCL relationships (qcl-Type1, qcl-Type2) for the target RS. At this time, each QCL information (QCL-Info) included in each TCI state can include the serving cell index and BWP index of the reference RS indicated by the corresponding QCL information, the type and ID of the reference RS, and the QCL type as shown in Table 14.

[0175]

[0176] FIG. 7 is a diagram illustrating an example of base station beam allocation according to TCI state settings in a wireless communication system according to one embodiment of the present disclosure. Referring to FIG. 7, an example of base station beam allocation according to TCI state settings is illustrated.

[0177] According to one embodiment, referring to FIG. 7, the base station can transmit information about N different beams to the terminal through N different TCI states. For example, in case of N=3 as shown in FIG. 7, the base station can notify that antenna ports referencing different TCI states (700, 705, or 710) have different spatial Rx parameters, i.e., are associated with different beams, by setting the qcl-Type2 parameter included in three TCI states (700, 705, 710) to be associated with CSI-RS or SSB corresponding to different beams and to QCL type D.

[0178] According to one embodiment, Tables 16 to 20 below show valid TCI state settings according to target antenna port type.

[0179] According to one embodiment, Table 16 shows valid TCI state settings when the target antenna port is a CSI-RS for tracking (TRS). TRS may refer to an NZP CSI-RS in which the repetition parameter is not set and trs-Info is set to true among CSI-RS. Setting 3 in Table 16 may be used for aperiodic TRS.

[0180]

[0181] According to one embodiment, Table 17 shows valid TCI state settings when the target antenna port is a CSI-RS for CSI. CSI-RS for CSI may mean an NZP CSI-RS in which a parameter indicating repetition (e.g., repetition parameter) among CSI-RSs is not set and trs-Info is not set to true.

[0182]

[0183] According to one embodiment, Table 18 shows valid TCI state settings when the target antenna port is CSI-RS for beam management (BM, which is synonymous with CSI-RS for L1 RSRP (Reference Signal Received Power) reporting). CSI-RS for BM may refer to an NZP CSI-RS in which the repetition parameter is set to On or Off among CSI-RSs and trs-Info is not set to true.

[0184]

[0185] According to one embodiment, Table 19 shows valid TCI state settings when the target antenna port is PDCCH DMRS.

[0186]

[0187] According to one embodiment, Table 20 shows valid TCI state settings when the target antenna port is PDSCH DMRS.

[0188]

[0189] According to one embodiment, a representative QCL configuration method according to Tables 16 to 20 operates by setting the target antenna port and reference antenna port for each step as 'SSB' -> 'TRS' -> 'CSI-RS for CSI, or CSI-RS for BM, or PDCCH DMRS, or PDSCH DMRS'. Through this, it is possible to link statistical characteristics that can be measured from SSB and TRS to each antenna port to assist the reception operation of the terminal.

[0190] [PDCCH: TCI state related]

[0191] Specifically, the TCI state combinations applicable to the PDCCH DMRS antenna port are as shown in Table 21 below. The fourth row in Table 21 is the combination assumed by the terminal before RRC configuration, and configuration after RRC is not possible.

[0192]

[0193] FIG. 8 is a diagram illustrating an example of a TCI state allocation method for a PDCCH in a wireless communication system according to one embodiment of the present disclosure.

[0194] According to one embodiment, NR may support a hierarchical signaling method as illustrated in FIG. 8 for dynamic allocation of PDCCH beams. Referring to FIG. 8, a base station may set N TCI states (805, 810, ..., 820) to a terminal via RRC signaling (800), and may set some of them as TCI states for CORESET (825). Thereafter, the base station may indicate one of the TCI states (830, 835, 840) for CORESET to the terminal via MAC CE signaling (845). Thereafter, the terminal may receive a PDCCH based on beam information included in the TCI state indicated by the MAC CE signaling.

[0195] FIG. 9 is a diagram illustrating a TCI indication MAC CE signaling structure for PDCCH DMRS in a wireless communication system according to one embodiment of the present disclosure.

[0196] According to one embodiment, FIG. 9 is a diagram illustrating a TCI indication MAC CE signaling structure for PDCCH DMRS. Referring to FIG. 9, the TCI indication MAC CE signaling for PDCCH DMRS is composed of 2 bytes (16 bits) and may include a 5-bit serving cell ID (915), a 4-bit CORESET ID (920), and a 7-bit TCI state ID (925).

[0197] FIG. 10 is a diagram illustrating an example of a control resource set and a beam setting of a search space in a wireless communication system according to one embodiment of the present disclosure.

[0198] According to one embodiment, referring to FIG. 10, the base station may indicate one of the TCI state lists included in the CORESET (1000) configuration via MAC CE signaling (1005). Thereafter, until another TCI state is indicated to the corresponding CORESET via another MAC CE signaling, the terminal may consider that the same QCL information (beam #1) (1005) is applied to all one or more search spaces (1010, 1015, 1020) connected to the CORESET. The above-described PDCCH beam allocation method has a problem that it is difficult to indicate a beam change faster than the MAC CE signaling delay, and also has a disadvantage that the same beam is applied to all CORESETs regardless of the search space characteristics, making flexible PDCCH beam operation difficult.

[0199] According to one embodiment, the following embodiments of the present invention can provide a more flexible PDCCH beam configuration and operation method. In describing the embodiments of the present invention below, several distinct examples are provided for convenience of explanation. However, these examples are not mutually exclusive and can be applied in appropriate combinations depending on the situation.

[0200] According to one embodiment, the base station can set one or more TCI states for a specific control region to the terminal, and can activate one of the set TCI states through a MAC CE activation command. For example, if {TCI state#0, TCI state#1, TCI state#2} are set as TCI states in control region #1, the base station can transmit a command to the terminal to activate TCI state#0 for control region #1 through MAC CE. The terminal can correctly receive DMRS of the corresponding control region based on QCL information in the activated TCI state based on the activation command for the TCI state received through MAC CE.

[0201] According to one embodiment, for a control region (control region #0) whose index is set to 0, if the terminal has not received a MAC CE activation command for the TCI state of control region #0, the terminal may assume that the SS / PBCH block identified in the initial access process or the non-contention-based random access process that is not triggered by a PDCCH command for the DMRS transmitted in control region #0 is QCL.

[0202] In one embodiment, for a control region (control region #X) whose index is set to a value other than 0, if the terminal has not set a TCI state for the control region #X, or has set one or more TCI states but has not received a MAC CE activation command that activates one of them, the terminal may assume that the DMRS transmitted in the control region #X is QCL'd with the SS / PBCH block identified during the initial access process.

[0203] [Rate matching / Puncturing related]

[0204] According to various embodiments of the present disclosure, rate matching operations and puncturing operations are specifically described.

[0205] According to one embodiment, 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 a resource C in the area where resources A and B overlap. The specific operations may follow the contents below.

[0206] Rate Matching Operation

[0207] According to one embodiment, the base station may map and transmit channel A only for the remaining resource regions excluding resource C corresponding to the overlapping region with resource B among the entire resources A to which the symbol sequence A is to be transmitted 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 may sequentially map and transmit symbol sequence A to {resource #1, resource #2, resource #4}, which are the remaining resources among resources A excluding {resource #3} corresponding to resource C. As a result, the base station may map and transmit symbol sequences {symbol #1, symbol #2, symbol #3} to {resource #1, resource #2, resource #4}, respectively.

[0208] According to one embodiment, the terminal can determine resources A and resource 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 has been mapped and transmitted in the remaining area except for resource C among the entire resources A. 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 symbol sequence A has been sequentially mapped to {resource #1, resource #2, resource #4}, which are the remaining resources among resources A except for {resource #3} corresponding to resource C. As a result, the terminal can assume that the symbol sequence {symbol #1, symbol #2, symbol #3} is transmitted by being mapped to {resource #1, resource #2, resource #4}, respectively, and perform a series of subsequent receiving operations.

[0209] Puncturing action

[0210] According to one embodiment, if there is a resource C corresponding to an area overlapping with resource B among all resources A to which the base station wishes to transmit symbol sequence A to the terminal, the base station may map symbol sequence A to the entire resource A, but may not perform transmission in the resource area corresponding to resource C, and may 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.

[0211] According to one embodiment, 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.

[0212] In one embodiment, the following describes a method for configuring rate matching resources for the purpose of rate matching in a 5G communication system. Rate matching may refer to adjusting the size of a signal based on the amount of resources available for signal transmission. For example, rate matching of a data channel may refer to adjusting the size of data accordingly, without mapping the data channel to a specific time and frequency resource region.

[0213] FIG. 11 is a diagram for explaining a method for a base station and a terminal to transmit and receive data in consideration of a downlink data channel and rate matching resources in a wireless communication system according to one embodiment of the present disclosure.

[0214] Figure 11 illustrates a downlink data channel (PDSCH) (1101) and rate matching resources (1102). In one embodiment, a base station may configure one or more rate matching resources (1102) to a terminal via higher layer signaling (e.g., RRC signaling).

[0215] According to one embodiment, the rate matching resource (1102) setting information may include time-axis resource allocation information (1103), frequency-axis resource allocation information (1104), and period information (1105). In the following, the bitmap corresponding to the frequency-axis resource allocation information (1104) is named "the first bitmap", the bitmap corresponding to the time-axis resource allocation information (1103) is named "the second bitmap", and the bitmap corresponding to the period information (1105) is named "the third bitmap".

[0216] According to one embodiment, if all or part of the time and frequency resources of a scheduled data channel (1101) overlap with the set rate matching resources (602), the base station can rate-match and transmit the data channel (1101) in the rate matching resource (1102) portion, and the terminal can perform reception and decoding after assuming that the data channel (1101) is rate-matched in the rate matching resource (1102) portion.

[0217] According to one embodiment, the base station can dynamically notify the terminal via DCI whether to rate-match the data channel in the rate-matching resource portion configured through additional configuration (corresponding to the "rate-matching indicator" in the DCI format described above). Specifically, the base station can select some of the configured 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 configured, 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".

[0218] In one embodiment, 5G can support "RB symbol level" and "RE level" granularity by setting the aforementioned rate matching resources in a terminal. More specifically, the following setting method can be followed.

[0219] RB symbol level

[0220] According to one embodiment, a terminal may be configured with up to four RateMatchPatterns for each bandwidth segment through upper layer signaling, and one RateMatchPattern may include the following contents.

[0221] In one embodiment, a reserved resource within a bandwidth portion may include 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. The reserved resource may span one or two slots. A time domain pattern (periodicityAndPattern) in which the time and frequency domains composed of each pair of bitmaps at the RB level and symbol level are repeated may additionally be set.

[0222] In one embodiment, the bandwidth portion may include a time and frequency domain resource region set as a control resource set and a resource region corresponding to a time domain pattern set as a search space setting in which the resource region is repeated.

[0223] RE level

[0224] According to one embodiment, the terminal may be configured with the following contents through upper layer signaling.

[0225] According to one embodiment, the configuration information (lte-CRS-ToMatchAround) for REs corresponding to an LTE CRS (Cell-specific Reference Signal or Common Reference Signal) pattern may include the number of ports (nrofCRS-Ports) of LTE CRS and the LTE-CRS-vshift(s) value (v-shift), information on the location of a center subcarrier (Subcarrier) of an LTE carrier from a reference frequency point (e.g., reference point A) (carrierFreqDL), information on the bandwidth size (carrierBandwidthDL) of the LTE carrier, and subframe configuration information (mbsfn-SubframConfigList) corresponding to an MBSFN (Multicast-broadcast single-frequency network). Based on the above-described information, the terminal may determine the location of the CRS within the NR slot corresponding to the LTE subframe.

[0226] According to one embodiment, it may include configuration information for a set of resources corresponding to one or more ZP (Zero Power) CSI-RSs within a bandwidth portion.

[0227] [Regarding LTE CRS rate match]

[0228] According to various embodiments of the present disclosure, the rate match process for the LTE CRS described above will be described in detail below. According to one embodiment, for coexistence of LTE (Long Term Evolution) and NR (New RAT) (LTE-NR Coexistence), NR may provide a function for setting a pattern of an LTE CRS (Cell Specific Reference Signal) to an NR terminal. More specifically, the CRS pattern may be provided by RRC signaling including at least one parameter in a ServingCellConfig IE (Information Element) or a ServingCellConfigCommon IE. Examples of the parameters described above may include lte-CRS-ToMatchAround, lte-CRS-PatternList1-r16, lte-CRS-PatternList2-r16, crs-RateMatch-PerCORESETPoolIndex-r16, etc.

[0229] In one embodiment, Rel-15 NR may provide a function that allows one CRS pattern to be configured per serving cell via the lte-CRS-ToMatchAround parameter. In Rel-16 NR, the above-described function is extended to allow multiple CRS patterns to be configured per serving cell. More specifically, a single-TRP (transmission and reception point) configured terminal may be configured with one CRS pattern per LTE carrier, and a multi-TRP configured terminal may be configured with two CRS patterns per LTE carrier. For example, a single-TRP configured terminal may be configured with up to three CRS patterns per serving cell via the lte-CRS-PatternList1-r16 parameter. As another example, a multi-TRP configured terminal may be configured with a CRS 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 are applied to a specific PDSCH (Physical Downlink Shared Channel) or only the CRS pattern for one TRP 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 can be applied.

[0230] In one embodiment, Table 22 illustrates a ServingCellConfig IE containing a CRS pattern, and Table 23 illustrates a RateMatchPatternLTE-CRS IE containing at least one parameter for a CRS pattern.

[0231]

[0232]

[0233]

[0234] [PDCCH: QCL prioritization rule related]

[0235] According to various embodiments of the present disclosure, the QCL priority determination operation for PDCCH is specifically described below.

[0236] In one embodiment, when a terminal operates in single-cell or band carrier aggregation (CA), and multiple control resource sets existing in an activated bandwidth portion of a single or multiple cells have the same or different QCL-TypeD characteristics and overlap in time during a specific PDCCH monitoring interval, the terminal may select a specific control resource set according to a QCL priority determination operation and monitor control resource sets having the same QCL-TypeD characteristics as the selected control resource set. That is, when multiple control resource sets overlap in time, only one QCL-TypeD characteristic may be received. In this case, the criteria for determining the QCL priority may be as follows.

[0237] - Criterion 1. A set of control resources connected to the common search section with the lowest index within the cell corresponding to the lowest index among the cells containing the common search section.

[0238] - Criterion 2. The control resource set associated with the terminal-specific search section with the lowest index within the cell corresponding to the lowest index among the cells containing the terminal-specific search section.

[0239] In one embodiment, as described above, each criterion may apply the next criterion if the corresponding criterion is not satisfied. For example, if control resource sets overlap in time in a specific PDCCH monitoring interval, and if all control resource sets are not connected to a common search interval but to a terminal-specific search interval, i.e., if criterion 1 is not satisfied, the terminal may skip applying criterion 1 and apply criterion 2.

[0240] According to one embodiment, when a terminal selects a control resource set by the above-described criteria, the terminal may additionally consider two things about the QCL information set in the control resource set. First, if control resource set 1 has CSI-RS 1 as a reference signal having a QCL-TypeD relationship, and the reference signal of this CSI-RS 1 having a QCL-TypeD relationship is SSB 1, and another control resource set 2 has a reference signal having a QCL-TypeD relationship that is SSB 1, the terminal may consider that these two control resource sets 1 and 2 have different QCL-TypeD characteristics. Second, if control resource set 1 has CSI-RS 1 set in cell 1 as a reference signal having a QCL-TypeD relationship, and the reference signal of this CSI-RS 1 having a QCL-TypeD relationship is SSB 1, and control resource set 2 has CSI-RS 2 set in cell 2 as a reference signal having a QCL-TypeD relationship, and the reference signal of this CSI-RS 2 having a QCL-TypeD relationship is the same SSB 1, then the terminal can consider that the two control resource sets have the same QCL-TypeD characteristic.

[0241] FIG. 12 is a diagram for explaining a method for selecting a set of control resources that can be received by a terminal in consideration of priority when receiving a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0242] In one embodiment, for example, a terminal may be configured to receive multiple control resource sets that overlap in time in a specific PDCCH monitoring interval (1210), and these multiple control resource sets may be connected to a common search space or a terminal-specific search space for multiple cells.

[0243] According to one embodiment, within the corresponding PDCCH monitoring section, there may be a control resource set (1215) connected to a common search section (1) within a bandwidth portion (1200) of a cell (1), and there may be a control resource set (1220) connected to a common search section (1) and a control resource set (1225) connected to a terminal-specific search section (2) within a bandwidth portion (1205) of a cell (2). The control resource sets (1215) and (1220) may have a relationship of QCL-TypeD with the CSI-RS resource (1) set within the bandwidth portion (1) of a cell (1), and the control resource set (1225) may have a relationship of QCL-TypeD with the CSI-RS resource (1) set within the bandwidth portion (1) of a cell (2). Therefore, if criterion 1 is applied to the corresponding PDCCH monitoring section (1210), all other control resource sets having the same QCL-TypeD reference signal as control resource set 1 (1215) can be received. Accordingly, the terminal can receive control resource sets (1215) and (1220) in the corresponding PDCCH monitoring section (1210).

[0244] According to one embodiment, as another example, a terminal may be configured to receive multiple control resource sets that overlap in time in a specific PDCCH monitoring section (1240), and these multiple control resource sets may be connected to a common search space or a terminal-specific search space for multiple cells. Within the PDCCH monitoring section, within the first bandwidth portion (1230) of the first cell, there may exist a first control resource set (1245) connected to the first terminal-specific search section and a second control resource set (1250) connected to the second terminal-specific search section, and within the first bandwidth portion (1235) of the second cell, there may exist a first control resource set (1255) connected to the first terminal-specific search section and a second control resource set (1260) connected to the third terminal-specific search section. Control resource sets (1245) and (1250) have a relationship with the 1st CSI-RS resource set in the 1st bandwidth part of the 1st cell and QCL-TypeD, control resource set (1255) has a relationship with the 1st CSI-RS resource set in the 1st bandwidth part of the 2nd cell and QCL-TypeD, and control resource set (1260) can have a relationship with the 2nd CSI-RS resource set in the 1st bandwidth part of the 2nd cell and QCL-TypeD. However, if criterion 1 is applied to the corresponding PDCCH monitoring section (1240), there is no common search section, so the next criterion, criterion 2, can be applied. If criterion 2 is applied to the corresponding PDCCH monitoring section (1240), all other control resource sets having the same QCL-TypeD reference signal as the control resource set (1245) can be received. Accordingly, the terminal can receive the control resource set (1245) and (1250) in the corresponding PDCCH monitoring section (1240).

[0245] [PDSCH: Processing Time]

[0246] Next, we will explain the PDSCH processing procedure time. When a base station schedules a UE to transmit a PDSCH using DCI format 1_0, 1_1, or 1_2, the UE may require PDSCH processing time to receive the PDSCH by applying the transmission method indicated through the DCI (modulation and coding instruction index (MCS), demodulation reference signal-related information, time and frequency resource allocation information, etc.). NR takes this into account and defines the PDSCH processing time. The PDSCH processing time of the UE can follow the following [Mathematical Formula 2].

[0247] [Equation 2]

[0248]

[0249] According to one embodiment, T described in mathematical expression 2 proc,1 In , each variable can have the following meanings:

[0250] - N1: The number of symbols determined by the UE processing capability 1 or 2 and the numerology μ according to the capability of the terminal. If the UE processing capability is reported as 1 according to the capability report of the terminal, it may have the value of [Table 24]. If the UE processing capability is reported as 2 and the availability of the UE processing capability 2 is set through upper layer signaling, it may have the value of [Table 25]. The numerology μ is T proc,1 to maximize μ PDCCH , μ PDSCH , μ UL It can correspond to the minimum value of μ PDCCH , μ PDSCH , μ ULEach may mean the numerology of the PDCCH that schedules the PDSCH, the numerology of the scheduled PDSCH, and the numerology of the uplink channel on which HARQ (hybrid automatic retransmission request)-ACK (acknowledgement) is to be transmitted.

[0251]

[0252]

[0253] - k: 64

[0254] - T ext : If the terminal uses a shared spectrum channel access method, the terminal is T ext can be calculated and applied to the PDSCH processing time. Otherwise, T ext can be assumed to be 0.

[0255] - If l1 indicating the PDSCH DMRS location value is 12, N1,0 in [Table x2-2] has a value of 14, otherwise it has a value of 13.

[0256] - For PDSCH mapping type A, if the last symbol of the PDSCH is the i-th symbol in the slot in which the PDSCH is transmitted, and i < 7, then d 1,1 is 7-i, otherwise d 1,1 is 0.

[0257] - d2: When a PUCCH with a high priority index and a PUCCH or PUSCH with a low priority index overlap in time, d2 of the PUCCH with the high priority index may be set to a value reported by the terminal. Otherwise, d2 is 0.

[0258] - If PDSCH mapping type B is used for terminal processing capability 1, d 1,1The value can be determined based on the number of symbols L of the scheduled PDSCH and the number d of overlapping symbols between the PDCCH that schedules the PDSCH and the scheduled PDSCH.

[0259] - If L≥7, then d 1,1 = 0.

[0260] - If L≥4 and L≤6, d 1,1 = 7 - L.

[0261] - If L = 3, d 1,1 = min (d, 1).

[0262] - If L = 2, d 1,1 = 3 + d.

[0263] - If PDSCH mapping type B is used for terminal processing capability 2, d 1,1 The value can be determined based on the number of symbols L of the scheduled PDSCH and the number d of overlapping symbols between the PDCCH that schedules the PDSCH and the scheduled PDSCH.

[0264] - If L≥7, then d 1,1 = 0.

[0265] - If L≥4 and L≤6, d 1,1 = 7 - L.

[0266] - If L = 2,

[0267] - If the scheduled PDCCH exists within a CORESET consisting of three symbols, and the CORESET and the scheduled PDSCH have the same start symbol, d 1,1 = 3.

[0268] - If not, d 1,1 = d.

[0269] - For a terminal supporting capability 2 within a given serving cell, the PDSCH processing time according to terminal processing capability 2 can be applied when the terminal sets processingType2Enabled, which is an upper layer signaling for the cell, to enable.

[0270] According to one embodiment, if the position of the first uplink transmission symbol of the PUCCH containing HARQ-ACK information (the position may be considered K1, which is defined as the transmission time of the HARQ-ACK, PUCCH resources used for HARQ-ACK transmission, and timing advance effects) is T after the last symbol of the PDSCH, proc,1 If the first uplink transmission symbol that appears after a time interval of T is not started, the terminal must transmit a valid HARQ-ACK message. That is, the terminal must transmit a PUCCH containing a HARQ-ACK only when there is sufficient PDSCH processing time. Otherwise, the terminal cannot provide the base station with valid HARQ-ACK information corresponding to the scheduled PDSCH. proc,1 can be used for both general and extended CP cases. In case of PDSCH with two PDSCH transmission locations within one slot, d 1,1 can be calculated based on the first PDSCH transmission position within the slot.

[0271] [PDSCH: Reception Preparation Time during Cross-Carrier Scheduling]

[0272] Next, the numerology μ in which the scheduled PDCCH is transmitted PDCCH μ, which is the numerology through which the PDSCH scheduled through the corresponding PDCCH is transmitted. PDSCHIn case of different cross-carrier scheduling, N is the PDSCH reception preparation time of the terminal defined for the time interval between the PDCCH and the PDSCH. pdsch Explains about.

[0273] In one embodiment, if μ PDCCH < μ PDSCH In this case, the scheduled PDSCH is N from the last symbol of the PDCCH that scheduled the PDSCH. pdsch It cannot be transmitted before the first symbol of the slot that follows the symbol. The transmission symbol of the corresponding PDSCH may include a DM-RS.

[0274] In one embodiment, if μ PDCCH > μ PDSCH In this case, the scheduled PDSCH is N from the last symbol of the PDCCH that scheduled the PDSCH. pdsch It can be transmitted from the symbol onwards. The transmission symbol of the corresponding PDSCH can include DM-RS.

[0275] According to one embodiment, N according to the scheduled PDCCH subcarrier spacing pdsch is as follows.

[0276]

[0277] [SRS related]

[0278] Next, we describe an uplink channel estimation method using the Sounding Reference Signal (SRS) transmission of a terminal. The base station can configure at least one SRS configuration for each uplink BWP to convey configuration information for SRS transmission to the terminal, and can also configure at least one SRS resource set for each SRS configuration. For example, the base station and the terminal can exchange the following upper-level signaling information to convey information regarding the SRS resource set.

[0279] - srs-ResourceSetId: SRS resource set index

[0280] - srs-ResourceIdList: A set of SRS resource indices referenced in the SRS resource set.

[0281] - resourceType: This is the time axis transmission setting of the SRS resource referenced in the SRS resource set, and can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. If set to 'periodic' or 'semi-persistent', associated CSI-RS information can be provided depending on the usage of the SRS resource set. If set to 'aperiodic', an aperiodic SRS resource trigger list and slot offset information can be provided, and associated CSI-RS information can be provided depending on the usage of the SRS resource set.

[0282] - usage: This is a setting for the usage of the SRS resource referenced in the SRS resource set, and can be set to one of 'beamManagement', 'codebook', 'nonCodebook', and 'antennaSwitching'.

[0283] - alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Parameter settings for adjusting the transmission power of SRS resources referenced in the SRS resource set can be provided.

[0284] According to one embodiment, the terminal may understand that the SRS resource included in the set of SRS resource indices referenced in the SRS resource set follows the information set in the SRS resource set.

[0285] In one embodiment, the base station and the terminal may also transmit and receive upper layer signaling information to convey individual configuration information for the SRS resource. For example, the individual configuration information for the SRS resource may include time-frequency axis mapping information within the slot of the SRS resource, which may include information on frequency hopping within or between slots of the SRS resource. In addition, the individual configuration information for the SRS resource may include a time axis transmission configuration of the SRS resource, which may be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. This may be restricted to have the same time axis transmission configuration as the SRS resource set including the SRS resource. If the time axis transmission configuration of the SRS resource is set to 'periodic' or 'semi-persistent', the SRS resource transmission period and slot offset (e.g., periodicityAndOffset) may additionally be included in the time axis transmission configuration.

[0286] According to one embodiment, the base station can activate, deactivate, or trigger SRS transmission to the terminal through higher layer signaling including RRC signaling or MAC CE signaling, or L1 signaling (e.g., DCI). For example, the base station can activate or deactivate periodic SRS transmission to the terminal through higher layer signaling. The base station can instruct the terminal to activate an SRS resource set in which resourceType is set to periodic through higher layer signaling, and the terminal can transmit an SRS resource referenced in the activated SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and the slot mapping including the transmission period and slot offset follows periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information set in the SRS resource, or can refer to the associated CSI-RS information set in the SRS resource set including the SRS resource. A terminal can transmit SRS resources within an activated uplink BWP for periodic SRS resources activated through upper layer signaling.

[0287] According to one embodiment, for example, a base station can activate or deactivate semi-persistent SRS transmission to a terminal through upper layer signaling. The base station can instruct the terminal to activate an SRS resource set through MAC CE signaling, and the terminal can transmit an SRS resource referenced in the activated SRS resource set. The SRS resource set activated through MAC CE signaling can be limited to an SRS resource set in which resourceType is set to semi-persistent. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and the slot mapping including the transmission period and slot offset follows periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information set in the SRS resource, or can refer to the associated CSI-RS information set in the SRS resource set including the SRS resource. If spatial relation info is configured in an SRS resource, the spatial domain transmission filter can be determined by referring to the configuration information for spatial relation info transmitted through MAC CE signaling that activates semi-persistent SRS transmission without following it. The terminal can transmit SRS resources within the activated uplink BWP for the semi-persistent SRS resource activated through upper layer signaling.

[0288] According to one embodiment, for example, a base station can trigger aperiodic SRS transmission to a terminal via DCI. The base station can indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) via the SRS request field of the DCI. The terminal can understand that an SRS resource set including the aperiodic SRS resource trigger indicated via the DCI in the aperiodic SRS resource trigger list among the configuration information of the SRS resource set has been triggered. The terminal can transmit an SRS resource referenced in the triggered SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource. In addition, the slot mapping of the transmitted SRS resource can be determined through a slot offset between a PDCCH including the DCI and the SRS resource, which can refer to value(s) included in a slot offset set configured in the SRS resource set. Specifically, the slot offset between the PDCCH including DCI and the SRS resource may be applied by applying the value indicated in the time domain resource assignment field of the DCI among the offset value(s) included in the slot offset set configured in the SRS resource set. In addition, the spatial domain transmission filter applied to the transmitted SRS resource may refer to the spatial relation information configured in the SRS resource, or may refer to the associated CSI-RS information configured in the SRS resource set including the SRS resource.A terminal can transmit SRS resources within an activated uplink BWP for aperiodic SRS resources triggered via DCI.

[0289] According to one embodiment, when a base station triggers aperiodic SRS transmission to a terminal through DCI, a minimum time interval may be required between a PDCCH including the DCI that triggers aperiodic SRS transmission and the SRS to be transmitted, so that the terminal can transmit the SRS by applying configuration information for the SRS resource. The time interval for the SRS transmission of the terminal may be defined as the number of symbols between the last symbol of the PDCCH including the DCI that triggers aperiodic SRS transmission and the first symbol to which the first SRS resource to be transmitted among the SRS resource(s) is mapped. The minimum time interval may be determined with reference to the PUSCH preparation procedure time required for the terminal to prepare for PUSCH transmission. In addition, the minimum time interval may have a different value depending on the usage of the SRS resource set including the SRS resource to be transmitted. For example, the minimum time interval may be determined as N2 symbols defined in consideration of the terminal processing ability according to the capability of the terminal with reference to the PUSCH preparation procedure time of the terminal. In addition, considering the usage of the SRS resource set including the SRS resource being transmitted, if the usage of the SRS resource set is set to 'codebook' or 'antennaSwitching', the minimum time interval can be set to N2 symbols, and if the usage of the SRS resource set is set to 'nonCodebook' or 'beamManagement', the minimum time interval can be set to N2+14 symbols.The terminal may transmit an aperiodic SRS if the time interval for aperiodic SRS transmission is greater than or equal to the minimum time interval, and may ignore the DCI that triggers the aperiodic SRS if the time interval for aperiodic SRS transmission is less than the minimum time interval.

[0290]

[0291] The spatialRelationInfo setting information in [Table 26] refers to a single reference signal and applies the beam information of the reference signal to the beam used for the corresponding SRS transmission. For example, the spatialRelationInfo setting may include information such as [Table 27] below.

[0292]

[0293] According to one embodiment, referring to the spatialRelationInfo setting, an index of a reference signal to be referenced in order to use beam information of a specific reference signal, i.e., an SS / PBCH block index, a CSI-RS index, or an SRS index, may be set. The upper signaling referenceSignal is setting information indicating which beam information of a reference signal is to be referenced for the corresponding SRS transmission, and ssb-Index may indicate an index of an SS / PBCH block, csi-RS-Index an index of a CSI-RS, and srs an index of an SRS, respectively. If the value of the upper signaling referenceSignal is set to 'ssb-Index', the terminal may apply the reception beam used when receiving the SS / PBCH block corresponding to the ssb-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'csi-RS-Index', the terminal may apply the reception beam used when receiving the CSI-RS corresponding to the csi-RS-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'srs', the terminal can apply the transmission beam used when transmitting the SRS corresponding to srs as the transmission beam for the corresponding SRS transmission.

[0294] [PUSCH: Transmission method related]

[0295] 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.

[0296] In one embodiment, a Configured grant Type 1 PUSCH transmission can be semi-statically configured by receiving a configuredGrantConfig including rrc-ConfiguredUplinkGrant of [Table 28] via higher-order signaling, without receiving a UL grant in the DCI. A Configured grant Type 2 PUSCH transmission can be semi-persistently scheduled by a UL grant in the DCI after receiving a configuredGrantConfig not including rrc-ConfiguredUplinkGrant of [Table 28] via higher-order signaling. When a PUSCH transmission operates by a configured grant, the parameters applied to the PUSCH transmission are applied by the configuredGrantConfig of the higher-order signaling of [Table 28], except for dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and scaling of UCI-OnPUSCH provided by the pusch-Config of the higher-order signaling of [Table 29]. If the terminal has been provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 28], the terminal can apply tp-pi2BPSK in pusch-Config of [Table 29] for PUSCH transmission operated by configured grant.

[0297]

[0298] According to one embodiment, the following describes a PUSCH transmission method. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission can follow a codebook-based transmission method or a non-codebook-based transmission method, respectively, depending on whether the value of txConfig in the pusch-Config of [Table 29], which is an upper signaling, is 'codebook' or 'nonCodebook'.

[0299] According to one embodiment, 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 a UE-specific PUCCH resource corresponding to the minimum ID within an activated uplink BWP within the serving cell, and at this time, the PUSCH transmission can be 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 29], the UE does not expect to be scheduled with DCI format 0_1.

[0300]

[0301] 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 can determine a precoder for PUSCH transmission based on the SRS Resource Indicator (SRI), the Transmission Precoding Matrix Indicator (TPMI), and the transmission rank (the number of PUSCH transmission layers).

[0302] In one embodiment, at this time, the SRI may be given through the field SRS resource indicator in the DCI or configured through the higher-level signaling srs-ResourceIndicator. The UE is configured with at least one SRS resource when transmitting a codebook-based PUSCH, and may be configured with up to two SRS resources. When the UE receives the SRI through the DCI, the SRS resource indicated by the SRI may refer to an SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH including the SRI. In addition, the TPMI and transmission rank may be given through the field precoding information and number of layers in the DCI or configured through the higher-level signaling precodingAndNumberOfLayers. The TPMI is used to indicate a precoder to be applied to the PUSCH transmission. If the UE is configured with one SRS resource, the TPMI is used to indicate a precoder to be applied in 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.

[0303] According to one embodiment, a 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 can determine the codebook subset based on the TPMI and the 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 the upper layer signaling codebookSubset 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'.

[0304] According to one embodiment, the terminal may 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 may 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 may expect that the value of nrofSRS-Ports in the upper signaling SRS-Resource is set to the same value for all SRS resources.

[0305] According to one embodiment, the terminal transmits to the base station one or more SRS resources included in an 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 a TPMI and rank to be used by the terminal for PUSCH transmission. The terminal can perform 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.

[0306] 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.

[0307] According to one embodiment, for an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'nonCodebook', the terminal may be configured with one connected NZP CSI-RS resource (non-zero power CSI-RS). The terminal may perform calculations for a precoder for SRS transmission through measurements on 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 terminal is less than 42 symbols, the terminal does not expect that information for the precoder for SRS transmission is updated.

[0308] In one embodiment, 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 field SRS request in DCI format 0_1 ​​or 1_1 is not '00'. At this time, the DCI may not indicate cross carrier or cross BWP scheduling. In addition, if the value of the SRS request indicates the presence of the 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.

[0309] In one embodiment, if a periodic or semi-persistent SRS resource set is configured, the associated NZP CSI-RS may be indicated through the associatedCSI-RS in the upper layer signaling SRS-ResourceSet. For non-codebook-based transmission, the UE does not expect the upper layer signaling spatialRelationInfo for the SRS resource and the associatedCSI-RS in the upper layer signaling SRS-ResourceSet to be configured together.

[0310] According to one embodiment, when a terminal is configured with multiple SRS resources, the terminal may determine a precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. At this time, the SRI may be indicated through the field SRS resource indicator in the DCI or may be configured through the upper signaling srs-ResourceIndicator. Similar to the codebook-based PUSCH transmission described above, when the terminal is provided with an SRI through the DCI, the SRS resource indicated by the SRI may refer to an SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH including the SRI. The terminal may 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 terminal to the base station. At this time, the SRS resources that the terminal simultaneously transmits may occupy the same RB. A terminal can configure one SRS port for each SRS resource. Only one SRS resource set with the usage value set to "nonCodebook" within the upper-level signaling, SRS-ResourceSet, can be configured, and up to four SRS resources for non-codebook-based PUSCH transmission can be configured.

[0311] According to one embodiment, a base station transmits one NZP-CSI-RS associated with an SRS resource set to a terminal, and the terminal can calculate a precoder to be used when transmitting one or more SRS resources within the SRS resource set based on a result measured upon reception of the NZP-CSI-RS. The terminal applies the calculated precoder when transmitting one or more SRS resources within the SRS resource set, of which usage is set to 'nonCodebook', to the base station, and the base station can select one or more SRS resources from among 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 can transmit the PUSCH by applying the precoder applied to SRS resource transmission to each layer.

[0312] [PUSCH: Preparation time]

[0313] 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 3].

[0314] [Equation 3]

[0315]

[0316] T described in mathematical formula 3 proc,2 In , each variable can have the following meanings:

[0317] - N2: The number of symbols determined by the terminal processing capability (UE processing capability) 1 or 2 and the numerology μ according to the terminal's capability.

[0318] According to one embodiment, if the terminal processing capability is reported as 1 according to the capability report of the terminal, it may have the value of [Table 30], and if the terminal processing capability is reported as 2 and it is set through upper layer signaling that the terminal processing capability 2 can be used, it may have the value of [Table 31].

[0319]

[0320]

[0321] - 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.

[0322] - k: 64

[0323] - 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, μ UL It can mean the numerology of the uplink in which PUSCH is transmitted.

[0324] - T c : has

[0325] - d 2,2 : If the DCI scheduling the PUSCH indicates BWP switching, it follows the BWP switching time, otherwise it has 0.

[0326] - 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.

[0327] - 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 can be assumed to be 0.

[0328] - T switch : T when the uplink switching interval is triggered switch can be assumed to be the switching interval time. Otherwise, it can be assumed to be 0.

[0329] According to one embodiment, when the base station and the terminal consider the time axis resource mapping information of the PUSCH scheduled through the DCI and the influence of the timing advance between uplink and downlink, the base station and the terminal may transmit 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 may be determined to be insufficient. If this is not the case, the base station and the UE may 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.

[0330] [PUSCH: multiplexing rule when AP / SP CSI reporting]

[0331] Hereinafter, a method for measuring and reporting channel states in a 5G communication system will be described in detail. Channel state information (CSI) may include a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), and / or an L1-RSRP (Reference Signal Received Power). A base station may control time and frequency resources for the above-described CSI measurement and reporting of a terminal.

[0332] According to one embodiment, for the above-described CSI measurement and reporting, the terminal may receive setting information (CSI-ReportConfig) for N (≥1) CSI reports, setting information (CSI-ResourceConfig) for M (≥1) RS transmission resources, and one or two trigger state lists (CSI-AperiodicTriggerStateList, CSI-SemiPersistentOnPUSCH-TriggerStateList) through upper layer signaling. The setting information for the above-described CSI measurement and reporting may be as described in more detail in [Table 32] to [Table 38] below.

[0333]

[0334]

[0335]

[0336]

[0337]

[0338]

[0339]

[0340]

[0341]

[0342]

[0343]

[0344]

[0345] According to one embodiment, for the above-described CSI report setting (CSI-ReportConfig), each report setting CSI-ReportConfig can be associated with one downlink (DL) bandwidth part identified by a higher layer parameter bandwidth part identifier (bwp-id) given by the CSI resource setting, CSI-ResourceConfig, associated with the corresponding report setting. For the time domain reporting operation for each report setting CSI-ReportConfig, 'Aperiodic', 'Semi-Persistent', and 'Periodic' methods are supported, which can be configured from the base station to the terminal by the reportConfigType parameter configured from the higher layer. The semi-persistent CSI reporting method can support 'PUCCH-based semi-persistent (semi-PersistentOnPUCCH)' and 'PUSCH-based semi-persistent (semi-PersistentOnPUSCH)'. For periodic or semi-permanent CSI reporting methods, the UE can receive PUCCH or PUSCH resources for transmitting CSI from the base station through higher-layer signaling. The period and slot offset of the PUCCH or PUSCH resources for transmitting CSI can be given as numerology of the uplink (UL) bandwidth portion configured for transmitting CSI reports. For aperiodic CSI reporting methods, the UE can receive scheduling for PUSCH resources for transmitting CSI from the base station through L1 signaling (the aforementioned DCI format 0_1).

[0346] According to one embodiment, for the CSI resource setting (CSI-ResourceConfig) described above, each CSI resource setting CSI-ReportConfig can include S (≥1) CSI resource sets (given by the upper layer parameter csi-RS-ResourceSetList). The CSI resource set list can be composed of a non-zero power (NZP) CSI-RS resource set and a SS / PBCH block set, or a CSI-interference measurement (CSI-IM) resource set. Each CSI resource setting can be located in a downlink (DL) bandwidth portion identified by the upper layer parameter bwp-id, and the CSI resource setting can be linked to a CSI reporting setting in the same downlink bandwidth portion. The time domain operation of the CSI-RS resources within the CSI resource setting can be set to one of 'aperiodic', 'periodic', or 'semi-persistent' from the upper layer parameter resourceType. For periodic or semi-permanent CSI resource settings, the number of CSI-RS resource sets can be limited to S=1, and the configured period and slot offset can be given as a numerology of a downlink bandwidth portion identified by bwp-id. A terminal can receive one or more CSI resource settings for channel or interference measurement from a base station through higher layer signaling, and may include, for example, the following CSI resources.

[0347] - CSI-IM resources for interference measurements

[0348] - NZP CSI-RS resources for interference measurements

[0349] - NZP CSI-RS resources for channel measurements

[0350] In one embodiment, for CSI-RS resource sets associated with resource settings where the upper layer parameter resourceType is set to 'aperiodic', 'periodic', or 'semi-persistent', a trigger state for CSI reporting settings where reportType is set to 'aperiodic' and a resource setting for channel or interference measurements for one or more component cells (CCs) may be set to the upper layer parameter CSI-AperiodicTriggerStateList.

[0351] According to one embodiment, aperiodic CSI reporting of a terminal may utilize PUSCH, periodic CSI reporting may utilize PUCCH, and semi-persistent CSI reporting may be performed using PUSCH when triggered or activated by DCI, or PUCCH after activation by MAC control element (MAC CE). As described above, CSI resource settings may also be configured aperiodic, periodic, or semi-persistent. Combinations between CSI reporting settings and CSI resource settings may be supported based on [Table 39] below.

[0352]

[0353] According to one embodiment, aperiodic CSI reporting may be triggered by the "CSI request" field of the aforementioned DCI format 0_1 ​​corresponding to scheduling DCI for PUSCH. The UE may monitor the PDCCH, acquire the DCI format 0_1, and acquire scheduling information and a CSI request indicator for the PUSCH. The CSI request indicator may be set to NTS (=0, 1, 2, 3, 4, 5, or 6) bits and may be determined by higher layer signaling (reportTriggerSize). One trigger state among one or more aperiodic CSI reporting trigger states that may be set by higher layer signaling (CSI-AperiodicTriggerStateList) may be triggered by the CSI request indicator.

[0354] In one embodiment, if all bits in the CSI request field are 0, this may mean that no CSI report is requested.

[0355] According to one embodiment, if the number of CSI trigger states (M) in the configured CSI-AperiodicTriggerStateLite is greater than 2NTs-1, then according to the predefined mapping relationship, the M CSI trigger states can be mapped to 2NTs-1, and one of the trigger states of 2NTs-1 can be indicated by the CSI request field.

[0356] According to one embodiment, if the number of CSI trigger states (M) in the configured CSI-AperiodicTriggerStateLite is less than or equal to 2NTs-1, one of the M CSI trigger states may be indicated in the CSI request field.

[0357] According to one embodiment, the following [Table 40] illustrates an example of a relationship between a CSI request indicator and a CSI trigger state that may be indicated by the indicator.

[0358]

[0359] According to one embodiment, a terminal may perform measurement on a CSI resource within a CSI trigger state triggered by a CSI request field, and may generate CSI (including at least one of the above-described CQI, PMI, CRI, SSBRI, LI, RI, or L1-RSRP) therefrom. The terminal may transmit the acquired CSI using a PUSCH scheduled by the corresponding DCI format 0_1. When 1 bit corresponding to an uplink data indicator (UL-SCH indicator) in the DCI format 0_1 ​​indicates "1", uplink data (UL-SCH) and the acquired CSI may be multiplexed and transmitted on the PUSCH resource scheduled by the DCI format 0_1. If 1 bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 ​​indicates "0", only CSI can be mapped and transmitted without uplink data (UL-SCH) to the PUSCH resource scheduled by DCI format 0_1.

[0360] FIG. 13 is a diagram illustrating an example of an aperiodic CSI reporting method according to one embodiment of the present disclosure.

[0361] According to one embodiment, in an example (1300) of FIG. 13, a terminal may monitor a PDCCH (1301) to obtain DCI format 0_1, from which scheduling information and CSI request information for a PUSCH (1305) may be obtained. The terminal may obtain resource information for a CSI-RS (1302) to be measured from the received CSI request indicator. The terminal can determine when to perform measurement on the transmitted CSI-RS (1302) resource based on the time point of receiving DCI format 0_1 ​​and the parameter (aperiodicTriggeringOffset described above) for the offset in the CSI resource set configuration (e.g., NZP CSI-RS resource set configuration (NZP-CSI-RS-ResourceSet)). More specifically, the terminal can receive an offset value X of the parameter aperiodicTriggeringOffset in the NZP-CSI-RS resource set configuration from the base station through upper layer signaling, and the set offset value X can mean an offset between a slot in which a DCI that triggers aperiodic CSI reporting is received and a slot in which a CSI-RS resource is transmitted. For example, the aperiodicTriggeringOffset parameter value and the offset value X can have a mapping relationship described in [Table 41] below.

[0362]

[0363] According to one embodiment, an example (1300) of FIG. 13 shows an example in which the offset value described above is set to X=0. In this case, the terminal can receive a CSI-RS (1302) in a slot (corresponding to slot 0 (1306) of FIG. 13) in which DCI format 0_1 ​​that triggers aperiodic CSI reporting is received, and can report CSI information measured with the received CSI-RS to the base station via PUSCH (1305). The terminal can obtain scheduling information (information corresponding to each field of the DCI format 0_1 ​​described above) for the PUSCH (1305) for CSI reporting from the DCI format 0_1. As an example, the terminal can obtain information on a slot in which the PUSCH (1305) is to be transmitted from the time domain resource allocation information for the PUSCH (1305) described above in the DCI format 0_1. In an example (1300) of FIG. 13, the terminal acquires a K2 value corresponding to a slot offset value for PDCCH-to-PUSCH as 3, and accordingly, the PUSCH (1305) can be transmitted in slot 3 (1309), which is 3 slots away from slot 0 (1306), at the time when the PDCCH (1301) is received.

[0364] According to one embodiment, in another example (1310) of FIG. 13, the terminal may monitor the PDCCH (1311) to obtain DCI format 0_1, and may obtain scheduling information and CSI request information for the PUSCH (1315) from the DCI format 0_1. The terminal may obtain resource information for the CSI-RS (1312) to be measured from the received CSI request indicator. An example (1310) of FIG. 13 shows an example in which the offset value for the CSI-RS described above is set to X=1. In this case, the terminal may receive the CSI-RS (1312) in a slot in which the DCI format 0_1 ​​that triggers aperiodic CSI reporting is received (corresponding to slot 0 (1316) of FIG. 13), and may report the CSI information measured with the received CSI-RS to the base station through the PUSCH (1315).

[0365] According to one embodiment, an aperiodic CSI report may include at least one or both of CSI part 1 and CSI part 2, and when the aperiodic CSI report is transmitted via a PUSCH, it may be multiplexed with a transport block. For multiplexing, a CRC may be inserted into the input bits of the aperiodic CSI, and then encoded and rate matched, and then mapped to a resource element in the PUSCH in a specific pattern and transmitted. The CRC insertion may be omitted depending on the coding method or the length of the input bits. The number of modulation symbols calculated for rate matching when multiplexing CSI Part 1 or CSI part 2 included in the aperiodic CSI report may be calculated as shown in [Table 42] below.

[0366]

[0367]

[0368] According to one embodiment, particularly in the case of PUSCH repetition transmission schemes A and B, the UE may multiplex and transmit an aperiodic CSI report only on the first repetition transmission among the PUSCH repetition transmissions. This is because the aperiodic CSI report information to be multiplexed is encoded in a polar code manner, and in this case, in order to be multiplexed on multiple PUSCH repetitions, each PUSCH repetition must have the same frequency and time resource allocation. In particular, in the case of PUSCH repetition type B, each actual repetition may have a different OFDM symbol length, and therefore the aperiodic CSI report may be multiplexed and transmitted only on the first PUSCH repetition.

[0369] In one embodiment, also, for PUSCH repetition transmission scheme B, if the UE schedules aperiodic CSI reporting without scheduling for a transport block or receives a DCI activating semi-persistent CSI reporting, the value of the nominal repetition may be assumed to be 1 even if the number of PUSCH repetition transmissions set by upper layer signaling is greater than 1. In addition, if the UE schedules or activates aperiodic or semi-persistent CSI reporting without scheduling for a transport block based on PUSCH repetition transmission scheme B, the UE may expect the first nominal repetition to be the same as the first actual repetition. For a PUSCH transmitted including semi-persistent CSI based on PUSCH repetition transmission scheme B without scheduling for a DCI after semi-persistent CSI reporting is activated by DCI, if the first nominal repetition is different from the first actual repetition, the transmission for the first nominal repetition may be ignored.

[0370] [PUSCH: Repetitive Transmission Related]

[0371] The following describes in detail the repetitive transmission of uplink data channels in 5G systems. 5G systems can support two types of repetitive transmission methods for uplink data channels: PUSCH repetitive transmission type A and PUSCH repetitive transmission type B. A terminal can be configured with either PUSCH repetitive transmission type A or B via higher-layer signaling.

[0372] PUSCH repetitive transmission type A

[0373] As described above, the symbol length and the position of the start symbol of the uplink data channel are determined by a time domain resource allocation method within one slot, and the base station can notify the terminal of the number of repeated transmissions through upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0374] According to one embodiment, the terminal may repeatedly transmit an uplink data channel having the same length and start symbol as the configured uplink data channel in consecutive slots based on the number of repeated transmissions received from the base station. In this case, if at least one symbol among the slots configured by the base station as downlink to the terminal or the symbols of the uplink data channel configured to the terminal is configured as downlink, the terminal may skip the uplink data channel transmission, but may count the number of repeated transmissions of the uplink data channel.

[0375] PUSCH repetitive transmission type B

[0376] As described above, the start symbol and length of the uplink data channel are determined by a time domain resource allocation method within one slot, and the base station can notify the terminal of the number of repetitions through upper signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0377] According to one embodiment, the nominal repetition of the uplink data channel is determined based on the start symbol and length of the uplink data channel that is first established as follows. The slot where the nth nominal repetition starts is The symbol given by and starting from that slot is is given by . The slot where the nth nominal repetition ends is The symbol given by and ending in that slot is is given by . Here, n=0,..., numberofrepetitions-1 and S represents the start symbol of the established uplink data channel and L represents the symbol length of the established uplink data channel. K s indicates the slot in which the PUSCH transmission starts. Indicates the number of symbols per slot.

[0378] In one embodiment, the UE may determine an invalid symbol for PUSCH repetition transmission type B. A symbol configured for downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated is determined as an invalid symbol for PUSCH repetition transmission type B. Additionally, an invalid symbol may be configured in a higher layer parameter (e.g., InvalidSymbolPattern). The higher layer parameter (e.g., InvalidSymbolPattern) may provide a symbol-level bitmap spanning one or two slots to configure an invalid symbol. 1 in the bitmap indicates an invalid symbol. Additionally, the period and pattern of the bitmap may be configured through a higher layer parameter (e.g., periodicityAndPattern). If a higher layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter indicates 1, the terminal applies the invalid symbol pattern, and if the parameter indicates 0, the terminal does not apply the invalid symbol pattern. If a higher layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter is not set, the terminal may apply the invalid symbol pattern.

[0379] In one embodiment, after determining invalid symbols, the terminal may consider symbols other than the invalid symbol as valid symbols for each nominal repetition. If each nominal repetition includes at least one valid symbol, the nominal repetition may include one or more actual repetitions. Here, each actual repetition includes a contiguous set of valid symbols that can be used for PUSCH repetitive transmission type B within a single slot.

[0380] FIG. 14 is a diagram illustrating an example of PUSCH repetition transmission type B in a wireless communication system according to one embodiment of the present disclosure.

[0381] In one embodiment, the terminal may set the start symbol S of the uplink data channel to 0, the length L of the uplink data channel to 14, and the number of repeated transmissions to 16. In this case, the nominal repetition is indicated in 16 consecutive slots (1401). Thereafter, the terminal may determine that the symbol set as the downlink symbol in each nominal repetition (1401) is an invalid symbol.

[0382] In one embodiment, the terminal may also determine symbols set to 1 in the invalid symbol pattern (1402) as invalid symbols. If valid symbols other than invalid symbols are composed of one or more consecutive symbols in one slot in each nominal repetition, they are set as actual repetition and transmitted (1403).

[0383] In one embodiment, also for PUSCH repetitive transmissions, NR Release 16 may define the following additional methods for UL grant-based PUSCH transmissions across slot boundaries and configured grant-based PUSCH transmissions.

[0384] - Method 1 (mini-slot level repetition): Two or more PUSCH repetitive transmissions are scheduled within a slot or across the boundaries of consecutive slots through a single UL grant. Furthermore, for Method 1, the time-domain resource allocation information in the DCI indicates the resources of the first repetitive transmission. Furthermore, the time-domain resource information of the first repetitive transmission and the time-domain resource information of the remaining repetitive transmissions can be determined based on the uplink or downlink direction determined for each symbol in each slot. Each repetitive transmission can occupy consecutive symbols.

[0385] - Method 2 (multi-segment transmission): Two or more repeated PUSCH transmissions are scheduled in consecutive slots through a single UL grant. At this time, one transmission is designated for each slot, and each transmission may have a different starting point or repetition length. In addition, in Method 2, the time-domain resource allocation information in the DCI indicates the starting point and repetition length of all repeated transmissions. In addition, when performing repeated transmissions in a single slot through Method 2, if there are multiple sets of consecutive uplink symbols in the slot, each repeated transmission is performed for each set of uplink symbols. If there is only one set of consecutive uplink symbols in the slot, one repeated PUSCH transmission is performed according to the method of NR Release 15.

[0386] - Method 3: Two or more repeated PUSCH transmissions are scheduled in consecutive slots via two or more UL grants. In this case, one transmission is designated for each slot, and the nth UL grant can be received before the PUSCH transmission scheduled for the n-1th UL grant ends.

[0387] - Method 4: One or more PUSCH repetitive transmissions within a single slot, or two or more PUSCH repetitive transmissions across the boundaries of consecutive slots, can be supported through one UL grant or one configured grant. The number of repetitions indicated by the base station to the terminal is only a nominal value, and the number of PUSCH repetitive transmissions actually performed by the terminal may be greater than the nominal number of repetitions. The time-domain resource allocation information in the DCI or the configured grant may indicate the resources of the first repetitive transmission indicated by the base station. The time-domain resource information of the remaining repetitive transmissions may be determined by referring to at least the resource information of the first repetitive transmission and the uplink or downlink direction of the symbols. If the time-domain resource information of the repetitive transmission indicated by the base station crosses a slot boundary or includes an uplink / downlink switchover point, the repetitive transmission may be divided into multiple repetitive transmissions. In this case, one repetitive transmission may be included for each uplink period within one slot.

[0388] [PUSCH: Frequency Hopping Process]

[0389] Below, we specifically describe frequency hopping of the uplink data channel (PUSCH) in a 5G system.

[0390] In one embodiment, 5G can support two methods for frequency hopping of uplink data channels for each PUSCH repetition transmission type. First, PUSCH repetition transmission type A can support intra-slot frequency hopping and inter-slot frequency hopping, and PUSCH repetition transmission type B can support inter-repetition frequency hopping and inter-slot frequency hopping.

[0391] According to one embodiment, the intra-slot frequency hopping method supported by PUSCH repetitive transmission type A is a method in which a terminal transmits by changing the allocated resources of the frequency domain by a set frequency offset in two hops within one slot. In intra-slot frequency hopping, the starting RB of each hop can be expressed using mathematical equation 4.

[0392] [Equation 4]

[0393]

[0394] In one embodiment, in Equation 4, i=0 and i=1 represent the first hop and the second hop, respectively, and RB start Indicates the starting RB within the UL BWP and is calculated from the frequency resource allocation method. RB offset The upper layer parameter indicates the frequency offset between two hops. The number of symbols in the first hop is can be represented as , and the number of symbols in the second hop is can be expressed as is the length of PUSCH transmission within one slot, expressed as the number of OFDM symbols.

[0395] According to one embodiment, the inter-slot frequency hopping method supported by the PUSCH repetitive transmission types A and B is a method in which the terminal changes the allocated resources of the frequency domain by a set frequency offset for each slot and transmits them. In inter-slot frequency hopping The starting RB during a slot can be expressed by Equation 5.

[0396] [Equation 5]

[0397]

[0398] In mathematical expression 5, is the current slot number, RB in multi-slot PUSCH transmission. start Indicates the starting RB within the UL BWP and is calculated from the frequency resource allocation method. RB offset Indicates the frequency offset between two hops through upper layer parameters.

[0399] According to one embodiment, the inter-repetition frequency hopping method supported by the PUSCH repetitive transmission type B is to transmit the allocated resources in the frequency domain for one or more actual repetitions within each nominal repetition by shifting them by a set frequency offset. RBstart(n), which is the index of the starting RB in the frequency domain for one or more actual repetitions within the nth nominal repetition, can follow the following mathematical expression 6.

[0400] [Equation 6]

[0401]

[0402] In one embodiment, in Equation 6, n is the index of nominal repetition, RB offset Indicates the RB offset between two hops via upper layer parameters.

[0403] [Regarding terminal capability reporting]

[0404] In LTE and NR, a terminal, while connected to a serving base station, can perform a procedure to report its supported capabilities to the base station. In the description below, this is referred to as a UE capability report.

[0405] According to one embodiment, a base station may transmit a UE capability inquiry message requesting a capability report to a connected terminal. The above-described message may include a UE capability request for each radio access technology (RAT) type of the base station. The RAT type-specific request may include information on a combination of supported frequency bands, etc. In addition, in the case of the UE capability inquiry message, UE capabilities for multiple RAT types may be requested through a single RRC message container transmitted by the base station, or the base station may include multiple UE capability inquiry messages including UE capability requests for each RAT type and transmit them to the terminal. In other words, the UE capability inquiry may be repeated multiple times within a single message, and the terminal may configure a corresponding UE capability information message and report it multiple times.

[0406] In one embodiment, a next-generation mobile communication system may request terminal capabilities for NR, LTE, EN-DC (E-UTRA - NR dual connectivity), and MR-DC (Multi-RAT dual connectivity). Furthermore, while terminal capability inquiry messages are typically transmitted initially after a terminal connects to a base station, they can be requested under any conditions when the base station requires them.

[0407] In one embodiment, a terminal that receives a UE capability report request from a base station in the above-described step can configure terminal capability based on the RAT type and band information requested from the base station. Below is a summary of how a terminal configures UE capability in an NR system.

[0408] 1. If the UE receives a list of LTE and / or NR bands through a UE capability request from the base station, the UE can configure a band combination (BC) for EN-DC and NR stand-alone (SA). That is, a candidate list of BCs for EN-DC and NR SA can be created based on the bands requested to the base station via FreqBandList. Furthermore, band priorities are prioritized in the order listed in FreqBandList.

[0409] 2. If the base station requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the UE may completely remove NR SA BCs from the configured BC candidate list. This action can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0410] 3. Afterwards, the terminal can remove fallback BCs from the BC candidate list constructed in the above-described step. Here, a fallback BC refers to a BC obtained by removing at least one band corresponding to an SCell from a random BC. This step can be omitted because the BC before removing the band corresponding to at least one SCell can already cover the fallback BC. This step also applies to MR-DC, i.e., to LTE bands. The BCs remaining after this step are the final "candidate BC list."

[0411] 4. The UE can select BCs to report by selecting BCs that match the requested RAT type from the final "candidate BC list". In this step, the UE can construct the supportedBandCombinationList in a set order. That is, the UE constructs BCs and UE capabilities to report in the order of the preset rat-Type (nr -> eutra-nr -> eutra). In addition, the UE can construct a featureSetCombination for the constructed supportedBandCombinationList, and construct a list of "candidate feature set combinations" from the candidate BC list after removing the list for the fallback BC (which contains capabilities of the same or lower level). The "candidate feature set combinations" include feature set combinations for both NR and EUTRA-NR BCs, and can be obtained from the feature set combinations in the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0412] 5. Also, if the requested rat Type is eutra-nr and is influencing, featureSetCombinations are included in both containers, UE-MRDC-Capabilities and UE-NR-Capabilities. However, the NR feature set is included only in UE-NR-Capabilities.

[0413] In one embodiment, after terminal capabilities are configured, the terminal may transmit a terminal capability information message containing the terminal capabilities to the base station. Based on the terminal capabilities received from the terminal, the base station may then perform appropriate scheduling and transmission / reception management for the terminal.

[0414] [CA / DC related]

[0415] FIG. 15 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation according to one embodiment of the present disclosure.

[0416] Referring to FIG. 15, the wireless protocol of the next-generation mobile communication system is composed of NR SDAP (Service Data Adaptation Protocol) (1525, 1570), NR PDCP (Packet Data Convergence Protocol) (1530, 1565), NR RLC (Radio Link Control) (1535, 1560), and NR MAC (Medium Access Control) (1540, 1555) in the terminal and NR base station, respectively.

[0417] According to one embodiment, the main functions of the NR SDAP (1525, 1570) may include some of the following functions:

[0418] - Transfer of user plane data

[0419] - Mapping function between QoS flow and data bearer for both DL and UL

[0420] - Marking function of QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0421] - Ability to map reflective QoS flow to data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0422] According to one embodiment, for an SDAP layer device, a terminal can be configured by an RRC message for each PDCP layer device, each bearer, or each logical channel, whether to use the header of the SDAP layer device or whether to use the function of the SDAP layer device, and when the SDAP header is configured, the terminal can be instructed to update or reset mapping information for QoS flows and data bearers of uplink and downlink through a 1-bit indicator for NAS reflective QoS and a 1-bit indicator for AS reflective QoS in the SDAP header. 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.

[0423] According to one embodiment, the main functions of the NR PDCP (1530, 1565) may include some of the following functions:

[0424] - Header compression and decompression (ROHC only)

[0425] - User data transfer function

[0426] - In-sequence delivery of upper layer PDUs

[0427] - Out-of-sequence delivery of upper layer PDUs

[0428] - PDCP PDU reordering for reception

[0429] - Duplicate detection of lower layer SDUs

[0430] - Retransmission function (Retransmission of PDCP SDUs)

[0431] - Encryption and decryption functions (Ciphering and deciphering)

[0432] - Timer-based SDU discard in uplink.

[0433] According to one embodiment, the reordering function of the NR PDCP device may include a function of reordering PDCP PDUs received from a lower layer in order based on a 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.

[0434] According to one embodiment, the main functions of the NR RLC (1535, 1560) may include some of the following functions:

[0435] - Data transfer function (Transfer of upper layer PDUs)

[0436] - In-sequence delivery of upper layer PDUs

[0437] - Out-of-sequence delivery of upper layer PDUs

[0438] - ARQ function (Error Correction through ARQ)

[0439] - Concatenation, segmentation and reassembly of RLC SDUs

[0440] - Re-segmentation of RLC data PDUs

[0441] - Reordering of RLC data PDUs

[0442] - Duplicate detection function

[0443] - Protocol error detection

[0444] - RLC SDU discard function

[0445] - RLC re-establishment function

[0446] In one embodiment, the in-sequence delivery function of an NR RLC device may mean the function of sequentially delivering RLC SDUs received from a lower layer to an upper layer.

[0447] According to one embodiment, the in-sequence delivery function of the NR RLC device may include a function of reassembling and delivering a single RLC SDU that was originally divided into multiple RLC SDUs and received, a function of reordering received RLC PDUs based on an RLC SN (sequence number) or a PDCP SN (sequence number), a function of recording lost RLC PDUs by reordering them, a function of reporting a status of lost RLC PDUs to the transmitting side, and a function of requesting retransmission of lost RLC PDUs.

[0448] In one embodiment, the in-sequence delivery function of the NR RLC device may include a function to sequentially deliver to the upper layer only the RLC SDUs up to the lost RLC SDU if 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 the 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 they are received (in the order of arrival, regardless of the order of the sequence number) and delivered to the PDCP device out of sequence (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 single complete RLC PDU, processed, and delivered to the PDCP device. The NR RLC layer may not include a concatenation function and the above-described function may be performed by the NR MAC layer or replaced with the multiplexing function of the NR MAC layer.

[0449] According to one embodiment, the out-of-sequence delivery function of the NR RLC device refers to a 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 multiple RLC SDUs when an original RLC SDU is received divided into multiple RLC SDUs, and a function of storing and arranging the RLC SN or PDCP SN of received RLC PDUs to record lost RLC PDUs.

[0450] According to one embodiment, the NR MAC (1540, 1555) may be connected to multiple NR RLC layer devices configured in one terminal, and the main functions of the NR MAC may include some of the following functions.

[0451] - Mapping function (Mapping between logical channels and transport channels)

[0452] - Multiplexing / demultiplexing of MAC SDUs

[0453] - Scheduling information reporting function

[0454] - HARQ function (Error correction through HARQ)

[0455] - Priority handling between logical channels of one UE

[0456] - Priority handling between UEs by means of dynamic scheduling

[0457] - MBMS service identification function

[0458] - Transport format selection function

[0459] - Padding function

[0460] According to one embodiment, the NR PHY layer (1545, 1550) may perform an operation of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it over a wireless channel, or demodulating and channel decoding OFDM symbols received over a wireless channel and transmitting them to an upper layer.

[0461] In one embodiment, the detailed structure of the wireless protocol structure may be changed in various ways 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 having a single structure for each layer, as in (1500). On the other hand, when the base station transmits data to a terminal based on carrier aggregation (CA) using multiple carriers in a single TRP, the base station and the terminal use a protocol structure having a single structure up to the RLC but multiplexing the PHY layer through the MAC layer, as in (1510). As another example, when a base station transmits data to a terminal based on DC (dual connectivity) using multiple carriers in multiple TRPs, the base station and the terminal use a protocol structure having a single structure up to the RLC but multiplexing the PHY layer through the MAC layer, as in (1520).

[0462] Referring to the descriptions related to the PDCCH and beam configuration described above, since repeated PDCCH transmission is not supported in the current Rel-15 and Rel-16 NR, it is 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 (e.g., transmission and reception points (TRPs)) to improve the PDCCH reception reliability of a terminal. The specific method is described in detail in the embodiments below.

[0463] According to one embodiment, embodiments of the present disclosure will be described in detail below with reference to the accompanying 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 a MAC (medium access control) control element (MAC control element; MAC CE).

[0464] According to one embodiment, in the present disclosure below, 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 the application of cooperative communication in a specific section indicated by a higher layer. For the convenience of the following description, the case in which the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to those described above will be referred to as the NC-JT (Non-Coherent Joint Transmission) case.

[0465] 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.

[0466] In the following disclosure, the above-described examples are described through various embodiments, but they are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0467] [NC-JT related]

[0468] According to one embodiment of the present disclosure, non-coherent joint transmission (NC-JT) may be used for a terminal to receive a PDSCH from multiple TRPs.

[0469] According to one embodiment, a 5G wireless communication system can support not only services requiring high transmission speeds, but also services with very short transmission delays and services requiring high connection density, unlike existing services. In a wireless communication network including multiple cells, transmission and reception points (TRPs), or beams, coordinated transmission between each cell, TRP, or / and beam can increase the strength of a signal received by a terminal or efficiently perform interference control between each cell, TRP, or / and beam, thereby satisfying various service requirements.

[0470] According to one embodiment, Joint Transmission (JT) is a representative transmission technology for the above-described cooperative communication, which increases the intensity or processing rate of a signal received by a terminal by transmitting a signal to a single terminal through a plurality of different cells, TRPs, or / and beams. In this case, the channel between each cell, TRP, or / and beam and the terminal may have significantly different characteristics, and in particular, in the case of Non-Coherent Joint Transmission (NC-JT) that supports non-coherent precoding between each cell, TRP, or / and beam, individual precoding, MCS, resource allocation, TCI indication, etc. may be required depending on the channel characteristics of each link between each cell, TRP, or / and beam and the terminal.

[0471] According to one embodiment, the NC-JT transmission described above may be applied to at least one channel among a downlink data channel (PDSCH), a downlink control channel (PDCCH), an uplink data channel (PUSCH), and an uplink control channel (PUCCH). When transmitting a PDSCH, transmission information such as precoding, MCS, resource allocation, and TCI are indicated by DL DCI, and for NC-JT transmission, the transmission information described above may need to be independently indicated for each cell, TRP, or / and beam. This is a major factor that increases the payload required for DL ​​DCI transmission, which may adversely affect the reception performance of the PDCCH transmitting the DCI. Therefore, in order to support JT of the PDSCH, it is necessary to carefully design a tradeoff between the amount of DCI information and the reception performance of control information.

[0472] FIG. 16 is a diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to an embodiment of the present disclosure. More specifically, FIG. 16 is a diagram illustrating an example of antenna port configuration and resource allocation for transmitting a PDSCH using cooperative communication.

[0473] According to one embodiment, referring to FIG. 16, an example for PDSCH transmission is described for each technique of Joint Transmission (JT), and examples for allocating radio resources for each TRP are shown.

[0474] In accordance with one embodiment, referring to FIG. 16, an example (1600) for Coherent Joint Transmission (C-JT) supporting coherent precoding between each cell, TRP, or / and beam is illustrated.

[0475] According to one embodiment, in the case of C-JT, TRP A (1605) and TRP B (1610) transmit a single data (PDSCH) to the terminal (1615), and joint precoding can be performed on multiple TRPs. This may mean that DMRS is transmitted through the same DMRS ports for TRP A (1605) and TRP B (1610) to transmit the same PDSCH. For example, TRP A (1605) and TRP B (1610) may each transmit DRMS ​​to the terminal through DMRS port A and DMRS B. In this case, the terminal may receive one DCI information for receiving one PDSCH that is demodulated based on the DMRS transmitted through DMRS port A and DMRS B.

[0476] According to one embodiment, FIG. 16 illustrates an example (1620) of Non-Coherent Joint Transmission (NC-JT) supporting non-coherent precoding between each cell, TRP, or / and beam for PDSCH transmission.

[0477] According to one embodiment, in the case of NC-JT, a PDSCH is transmitted to a terminal (1635) for each cell, TRP, or / and beam, and individual precoding may be applied to each PDSCH. Each cell, TRP, or / and beam may transmit a different PDSCH or a different PDSCH layer to the terminal, thereby improving throughput compared to single cell, TRP, or / and beam transmission. In addition, each cell, TRP, or / and beam may repeatedly transmit the same PDSCH to the terminal, thereby improving reliability compared to single cell, TRP, or / and beam transmission. For convenience of explanation, a cell, TRP, or / and beam may be collectively referred to as TRP hereinafter.

[0478] In one embodiment, various radio resource allocations may be considered, such as when the frequency and time resources used by the multiple TRPs for PDSCH transmission are all the same (1640), when the frequency and time resources used by the multiple TRPs do not overlap at all (1645), and when some of the frequency and time resources used by the multiple TRPs overlap (1650).

[0479] In one embodiment, DCIs of various shapes, structures and relationships may be considered to simultaneously allocate multiple PDSCHs to a single terminal to support NC-JT.

[0480] FIG. 17 is a diagram illustrating an example of configuring downlink control information (DCI) for cooperative communication in a wireless communication system according to one embodiment of the present disclosure. More specifically, FIG. 17 is a diagram illustrating an example of configuring downlink control information for NC-JT, in which each TRP transmits a different PDSCH or different PDSCH layers to a terminal.

[0481] According to one embodiment, referring to FIG. 17, case #1 (1700) is an example in which, in a situation in which (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to a serving TRP (TRP#0) used for single PDSCH transmission, control information for PDSCHs transmitted from the (N-1) additional TRPs is transmitted independently from the control information for the PDSCHs transmitted from the serving TRP. That is, the UE can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through independent DCIs (DCI#0 to DCI#(N-1)). The formats between the above-described independent DCIs may be the same or different, and the payloads between the DCIs may also be the same or different. In the case #1 described above, each PDSCH control or allocation freedom can be fully guaranteed, but if each DCI is transmitted in different TRPs, coverage differences may occur for each DCI, which may deteriorate reception performance.

[0482] According to one embodiment, case #2 (1705) shows an example in which, in addition to a serving TRP (TRP#0) used for single PDSCH transmission, (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)), control information (DCI) for the PDSCHs of the (N-1) additional TRPs is transmitted respectively, and each of these DCIs is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0483] For example, in the case of DCI#0, which is control information for a PDSCH transmitted from a serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, but in the case of shortened DCI (hereinafter, sDCI) (sDCI#0 to sDCI#(N-2)), which is control information for PDSCHs transmitted from cooperative TRPs (TRP#1 to TRP#(N-1)), it may include only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2. Therefore, in the case of sDCI, which transmits control information for PDSCHs transmitted from cooperative TRPs, since the payload is smaller than that of normal DCI (nDCI), which transmits PDSCH-related control information transmitted from a serving TRP, it is possible to include reserved bits compared to nDCI.

[0484] According to one embodiment, the case #2 described above may limit the degree of freedom of each PDSCH control or allocation depending on the content of the information element included in the sDCI, but since the reception performance of the sDCI is superior to that of the nDCI, the probability of a difference in coverage by DCI may be reduced.

[0485] According to one embodiment, case #3 (1710) illustrates an example in which, in a situation in which (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than a serving TRP (TRP#0) used for single PDSCH transmission, one control information for the PDSCHs of the (N-1) additional TRPs is transmitted, and this DCI is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0486] According to one embodiment, for example, in the case of DCI#0, which is control information for a PDSCH transmitted from a serving TRP (TRP#0), it is possible to include all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, and in the case of control information for PDSCHs transmitted from cooperating TRPs (TRP#1 to TRP#(N-1)), only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 are collected and transmitted in one 'secondary' DCI (sDCI). For example, sDCI may include at least one piece of information among HARQ-related information such as frequency domain resource assignment, time domain resource assignment, and MCS of cooperating TRPs. In addition, for information not included in sDCI, such as BWP (bandwidth part) indicator or carrier indicator, the DCI (DCI#0, normal DCI, nDCI) of serving TRP can be followed.

[0487] According to one embodiment, case #3 (1710) may limit the degree of freedom of each PDSCH control or allocation depending on the content of the information element included in the sDCI, but may allow for control of the reception performance of the sDCI and may reduce the complexity of DCI blind decoding of the terminal compared to case #1 (1700) or case #2 (1705).

[0488] According to one embodiment, case #4 (1715) is an example of transmitting control information for PDSCHs transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in the same DCI (Long DCI) as the control information for PDSCHs transmitted from the serving TRP in a situation where (N-1) different PDSCHs are transmitted from (N-1) additional TRPs in addition to the serving TRP (TRP#0) used for single PDSCH transmission. That is, the UE can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. In case #4 (1715), the complexity of DCI blind decoding of the UE may not increase, but the degree of freedom in PDSCH control or allocation may be low, such as because the number of cooperative TRPs is limited due to the long DCI payload limitation.

[0489] In the following descriptions and examples, sDCI may refer to various auxiliary DCIs, such as shortened DCI, secondary DCI, or normal DCI (DCI format 1_0 to 1_1 described above) containing PDSCH control information transmitted in a cooperative TRP, and unless a special limitation is specified, the description can be similarly applied to the various auxiliary DCIs described above.

[0490] In the following description and examples, the above-described cases #1 (1700), #2 (1705), and #3 (1710), in which more than one DCI (PDCCH) is used to support NC-JT, may be classified as multiple PDCCH-based NC-JT, and the above-described case #4 (1715), in which a single DCI (PDCCH) is used to support NC-JT, may be classified as single PDCCH-based NC-JT. In PDSCH transmission based on multiple PDCCH, a CORESET in which the DCI of the serving TRP (TRP#0) is scheduled and a CORESET in which the DCI of the cooperating TRPs (TRP#1 to TRP#(N-1)) are scheduled may be distinguished. As a method for distinguishing the CORESETs, there may be a method for distinguishing through an upper layer indicator for each CORESET, a method for distinguishing through beam setting for each CORESET, etc. Additionally, in single PDCCH-based NC-JT, instead of scheduling multiple PDSCHs with a single DCI, a single PDSCH with multiple layers is scheduled, and the multiple layers described above can be transmitted from multiple Transmission Relays (TRPs). In this case, the connection relationship between a layer and the TRP transmitting the layer can be indicated through a Transmission Configuration Indicator (TCI) indication for the layer.

[0491] In the embodiments of the present disclosure, “cooperative TRP” may be replaced with various terms such as “cooperative panel” or “cooperative beam” in actual application.

[0492] In the embodiments of the present disclosure, “when NC-JT is applied” can be interpreted in various ways depending on the situation, such as “when a terminal simultaneously receives one or more PDSCHs in one BWP,” “when a terminal simultaneously receives PDSCHs based on two or more TCI (Transmission Configuration Indicator) indications in one BWP,” or “when a PDSCH received by a terminal is associated with one or more DMRS port groups,” but is used as a single expression for convenience of explanation.

[0493] In the present invention, the wireless protocol structure for NC-JT can be used in various ways depending on the TRP deployment scenario. For example, when there is no or small backhaul delay between cooperative TRPs, a method (CA-like method) using a structure based on MAC layer multiplexing similar to (1510) of Fig. 15 is possible. On the other hand, when the backhaul delay between cooperative TRPs is large enough to be ignored (for example, when more than 2 ms is required for information exchange such as CSI, scheduling, and HARQ-ACK between cooperative TRPs), a method (DC-like method) is possible to secure delay-robust characteristics by using an independent structure for each TRP starting from the RLC layer similar to (1520) of Fig. 15.

[0494] According to one embodiment, a terminal supporting C-JT / NC-JT can receive C-JT / NC-JT related parameters or setting values ​​from a higher layer configuration and set the RRC parameters of the terminal based on the parameters. For the higher layer configuration, the terminal can utilize a UE capability parameter, for example, tci-StatePDSCH. Here, the UE capability parameter, for example, tci-StatePDSCH, can define TCI states for the purpose of PDSCH transmission, and the number of TCI states can be set to 4, 8, 16, 32, 64, 128 in FR1, and to 64, 128 in FR2, and up to 8 states that can be indicated by 3 bits of the TCI field of DCI through a MAC CE message among the set number can be set. The maximum value 128 can mean a value indicated by maxNumberConfiguredTCIstatesPerCC in the tci-StatePDSCH parameter included in the capability signaling of the terminal. In this way, a series of configuration processes from upper layer configuration to MAC CE configuration can be applied to a beamforming instruction or beamforming change command for at least one PDSCH in one TRP.

[0495] [Multi-DCI based Multi-TRP]

[0496] According to one embodiment of the present disclosure, a downlink control channel for NC-JT transmission can be set based on a multi-PDCCH.

[0497] In one embodiment, in an NC-JT based on multiple PDCCHs, when transmitting DCI for the PDSCH schedule of each TRP, a CORESET or search space may be provided for each TRP. The CORESET or search space for each TRP may be configured as in at least one of the following cases.

[0498] - Setting of upper layer index for each CORESET: The CORESET setting information set as an upper layer may include an index value, and the TRP transmitting the PDCCH in the corresponding CORESET may be distinguished by the set index value for each CORESET. That is, in a set of CORESETs with the same upper layer index value, it may be considered that the same TRP transmits the PDCCH, or it may be considered that the PDCCH scheduling the PDSCH of the same TRP is transmitted. The above-described index for each CORESET may be named as CORESETPoolIndex, and for CORESETs with the same CORESETPoolIndex value set, it may be considered that the PDCCH is transmitted from the same TRP. For a CORESET for which the CORESETPoolIndex value is not set, it may be considered that the default value of CORESETPoolIndex is set, and the above-described default value may be 0.

[0499] - Multiple PDCCH-Config settings: Multiple PDCCH-Configs are set within one BWP, and each PDCCH-Config can include PDCCH settings for each TRP. That is, a list of CORESETs for each TRP and / or a list of search spaces for each TRP can be configured in one PDCCH-Config, and one or more CORESETs and one or more search spaces included in one PDCCH-Config can be considered to correspond to a specific TRP.

[0500] - CORESET Beam / Beam Group Configuration: The TRP corresponding to the CORESET can be distinguished through the beam or beam group configured for each CORESET. For example, if the same TCI state is set for multiple CORESETs, the CORESETs can be considered to be transmitted through the same TRP, or the PDCCH that schedules the PDSCH of the same TRP can be considered to be transmitted in the CORESET.

[0501] - Search space beam / beam group configuration: A beam or beam group is configured for each search space, and this allows TRPs for each search space to be distinguished. For example, if the same beam / beam group or TCI state is set for multiple search spaces, it can be considered that the same TRP transmits a PDCCH in the corresponding search space, or that a PDCCH scheduling the PDSCH of the same TRP is transmitted in the corresponding search space.

[0502] As described above, since the CORESET or search space is divided by TRP, classification of PDSCH and HARQ-ACK information for each TRP is possible, and this enables independent HARQ-ACK codebook generation and independent PUCCH resource use for each TRP.

[0503] The above-described configuration can be independent for each cell or BWP. For example, a PCell may have two different CORESETPoolIndex values ​​configured, while a specific SCell may not have a CORESETPoolIndex value configured. In this case, it can be assumed that NC-JT transmission is configured for the PCell, while NC-JT transmission is not configured for the SCell without a CORESETPoolIndex value.

[0504] [Single-DCI based Multi-TRP]

[0505] According to another embodiment of the present disclosure, a downlink beam for NC-JT transmission can be set based on a single-PDCCH.

[0506] In one embodiment, in a single PDCCH-based NC-JT, a PDSCH transmitted by multiple TRPs can be scheduled with a single DCI. In this case, the number of TCI states can be used as a method of indicating the number of TRPs transmitting the corresponding PDSCH. That is, if the number of TCI states indicated in the DCI scheduling the PDSCH is two, it can be considered a single PDCCH-based NC-JT transmission, and if the number of TCI states is one, it can be considered a single-TRP transmission.

[0507] According to one embodiment, the TCI states indicated in the DCI described above may correspond to one or two TCI states among the TCI states activated by MAC-CE. When the TCI states of the DCI correspond to two TCI states activated by MAC-CE, a correspondence relationship between the TCI codepoint indicated in the DCI and the TCI states activated by MAC-CE is established, and this may be the case when there are two TCI states activated by MAC-CE corresponding to the TCI codepoint.

[0508] In one embodiment, the above-described configuration may be independent on a per-cell or per-BWP basis. For example, a PCell may have at most two activated TCI states corresponding to a single TCI codepoint, while a specific SCell may have at most one activated TCI state corresponding to a single TCI codepoint. In this case, it can be assumed that NC-JT transmission is configured on the PCell, while NC-JT transmission is not configured on the aforementioned SCell.

[0509] [PHR]

[0510] Figure 18 illustrates a procedure for a base station to control the transmission power of a terminal in a cellular system.

[0511] According to one embodiment, in step 1810 of FIG. 18, a terminal within the coverage area of ​​a base station may perform downlink synchronization with the base station and acquire system information. In some embodiments, downlink synchronization may be achieved through a synchronization signal (PSS / SSS) received from the base station. Terminals that have performed downlink synchronization may receive a Master Information Block (MIB) and a System Information Block (SIB) from the base station and acquire system information.

[0512] According to one embodiment, in step 1815, the terminal may perform uplink synchronization with the base station through a random access procedure and establish an RRC (Raido Resource Control) connection. In the random access procedure, the terminal may transmit a random access preamble and message 3 (msg3) to the base station through the uplink. At this time, uplink transmission power control may be performed when transmitting the random access preamble and message 3. Specifically, the terminal may receive parameters for uplink transmission power control from the base station through acquired system information, for example, SIB, or may control the uplink transmission power using agreed parameters. In another embodiment of the present disclosure, the terminal may measure a Reference Signal Received Power (RSRP) from a path loss estimation signal transmitted by the base station and estimate a downlink path loss value as shown in [Mathematical Formula 7]. Then, based on the estimated path loss value, an uplink transmission power value for transmitting the random access preamble and message 3 may be set.

[0513] [Equation 7]

[0514] Downlink path attenuation = base station signal transmission power - RSRP measured by terminal

[0515] According to one embodiment, the transmission power of the base station signal in [Mathematical Formula 7] may mean the transmission power of the downlink path attenuation estimation signal transmitted by the base station. The downlink path attenuation estimation signal transmitted by the base station may be a Cell-specific Reference Signal (CRS) or a Synchronization Signal Block (SSB). When the path attenuation estimation signal is a Cell-specific Reference Signal (CRS), the transmission power of the base station signal means the transmission power of the CRS, and may be transmitted to the terminal through the referenceSignalPower parameter of the system information. When the path attenuation estimation signal is a Synchronization Signal Block (SSB), the transmission power of the base station signal means the transmission power of the Secondary Synchronization Signal (SSS) and the Demodulation Reference signal (DMRS) transmitted on the PBCH, and may be transmitted to the terminal through the ss-PBCH-BlockPower parameter of the system information.

[0516] According to one embodiment, at step 1820, the terminal may receive RRC parameters for uplink transmission power control from the base station through UE-specific RRC or common RRC. The received transmission power control parameters may differ from each other depending on the type of uplink channel and signal transmitted in the uplink. That is, the transmission power control parameters applied to transmission of an uplink control channel (PUCCH), an uplink data channel (PUSCH), and a sounding reference signal (SRS) may differ from each other. In addition, as described above, the transmission power control parameters received by the terminal from the base station through SIB before establishing the RRC connection or the transmission power control parameters used by the terminal as a pre-agreed value before establishing the RRC connection may be included in the RRC parameters transmitted from the base station after establishing the RRC connection. The terminal may use the RRC parameter values ​​received from the base station after establishing the RRC connection for uplink transmission power control.

[0517] According to one embodiment, at step 1825, the terminal may receive a path loss estimation signal from the base station. More specifically, the base station may configure a Channel State Information-Reference Signal (CSI-RS) as the path loss estimation signal of the terminal after the terminal establishes an RRC connection. In this case, the base station may transmit information about the transmission power of the CSI-RS to the terminal through the powerControlOffsetSS parameter of the UE-dedicated RRC information. In this case, the powerControlOffsetSS may indicate the difference (offset) in transmission power between SSB and CSI-RS.

[0518] According to one embodiment, at step 1830, the terminal may estimate a downlink path attenuation value and set an uplink transmission power value. More specifically, the terminal may measure a downlink RSRP using CSI-RS and estimate a downlink path attenuation value using information about the transmission power of the CSI-RS received from the base station through [Mathematical Formula 7]. Then, based on the estimated path attenuation value, the terminal may set an uplink transmission power value for PUCCH, PUSCH, and SRS transmission.

[0519] In one embodiment, at step 1835, the terminal may report power headroom (PHR) to the base station. Power headroom may refer to the difference between the terminal's current transmission power and the terminal's maximum output power.

[0520] In one embodiment, at step 1840, the base station may optimize system operation based on the reported power headroom. For example, if a specific terminal reports a positive power headroom value to the base station, the base station may allocate more resources (e.g., RBs) to the terminal, thereby increasing system throughput.

[0521] In one embodiment, at step 1845, the terminal may receive a transmission power control command (TPC) from the base station. For example, if a power headroom value reported by a specific terminal to the base station is negative, the base station may allocate fewer resources to the terminal or reduce the terminal's transmission power via the TPC. This may increase system throughput or reduce unnecessary power consumption of the terminal.

[0522] In one embodiment, at step 1850, the terminal may update its transmit power based on a TPC command. The TPC command may be transmitted to the terminal via UE-specific DCI or group common DCI. Accordingly, the base station may dynamically control the terminal's transmit power via the TPC command.

[0523] According to one embodiment, at step 1855, the terminal may perform uplink transmission based on the updated transmission power.

[0524] [PUSCH power control]

[0525] The PUSCH transmission power can be determined through the following [Mathematical Formula 8].

[0526] [Equation 8]

[0527]

[0528] According to one embodiment, P in [Equation 8] CMAX,f,c (i) is the maximum transmission power set to the terminal for carrier f of serving cell c at PUSCH transmission time point i. is a reference transmission power setting value according to the activated uplink bandwidth part (BWP) b of carrier f of serving cell c, and has different values ​​depending on various transmission types j. It can have different values ​​depending on whether the PUSCH transmission is a message 3 PUSCH for random access, or whether the PUSCH is a configured grant PUSCH, or whether the PUSCH is a scheduled PUSCH. may mean the frequency size to which PUSCH is allocated. α b,f,c (j) represents the compensation ratio value for the path loss of UL BWP b of carrier f of serving cell c, which can be set by an upper signal and can have different values ​​depending on j. PL b,f,c (qd ) can use the value measured through the reference signal in the activated downlink bandwidth section as the downlink path loss estimate value of the UL BWP b of the carrier f of the serving cell c. The above-mentioned reference signal can be an SS / PBCH block or a CSI-RS.

[0529] According to one embodiment, the downlink path loss can be calculated as described in [Mathematical Formula 7]. In another embodiment of the present disclosure, PL b,f,c (q d ) is a downlink warning attenuation value, which is the path attenuation calculated by the terminal as in [Mathematical Formula 7]. The terminal can calculate the path attenuation based on the reference signal resource linked to the SS / PBCH block or CSI-RS depending on whether the upper signal is set. The above-described reference signal resource can be selected from among several sets of reference signal resources by the upper signal or L1 signal, and the terminal can calculate the path attenuation based on the reference signal resource. is a value determined by the MCS (Modulation and Coding Scheme) value of the PUSCH at the PUSCH transmission time point i of the UL BWP b of the carrier f of the serving cell c. f b,f,c (i,l) is a power control adaptation value that can dynamically adjust the power value by TPC command.

[0530] In one embodiment, the TPC command is divided into an accumulated mode and an absolute mode, and one of the two modes is determined by a higher level signal. The accumulated mode is a form in which the currently determined power control adaptation value is accumulated to the value indicated by the TPC command, and can be increased or decreased according to the TPC command, and f b,f,c (i,l)=f b,f,cIt has the relationship (i-i0,l)+∑δPUSCH,b,f,c. δPUSCH,b,f,c are the values ​​indicated by the TPC command. The absolute mode determines the value by the TPC command regardless of the currently determined power control adaptation value, and f b,f,c It has the relationship (i,l)=δPUSCH,b,f,c. [Table 43] below shows the values ​​that can be indicated in the TPC command.

[0531]

[0532] [PUCCH power control]

[0533] According to one embodiment, the following [Equation 9] is a mathematical equation for determining PUCCH transmission power.

[0534] [Equation 9]

[0535]

[0536] According to one embodiment, in [Equation 9] is the reference setting transmission power setting value, and various transmission types q u It has different values ​​depending on the subcarrier spacing, and the value can be changed by a higher level signal such as RRC or MAC CE. When the value is changed by MAC CE, the terminal can determine that the value is applied from slot k + koffset if the slot in which HARQ-ACK is transmitted for the PDSCH that received MAC CE is k. koffset has different values ​​depending on the subcarrier spacing, and can have 3ms as an example. is the size of the frequency resource region to which PUCCH is allocated. PL b,f,c (q d ) is the path attenuation estimation value of the terminal, and as described in [Mathematical Formula 7], the terminal can calculate it based on a specific reference signal among various CSI-RS or SS / PBCH depending on whether and what type of upper signal is set. For repetitively transmitted PUCCHs, the same q dis applied. For repetitive transmission PUCCHs, the same q u is applied.

[0537] [HARQ-ACK: Type 1 (semi-static) codebook related]

[0538] According to one embodiment, in a situation where the number of HARQ-ACK PUCCHs that a UE can transmit in a slot is limited to one, when the UE receives a semi-static HARQ-ACK codebook upper configuration, the UE may report HARQ-ACK information for PDSCH reception or SPS PDSCH release in the HARQ-ACK codebook in a slot indicated by the value of the PDSCH-to-HARQ_feedback timing indicator field in DCI format 1_0 or DCI format 1_1. The UE may report a HARQ-ACK information bit value as NACK (negative ACLK) in the HARQ-ACK codebook in a slot that is not indicated by the PDSCH-to-HARQ_feedback timing indicator field in DCI format 1_0 or DCI format 1_1. If a terminal reports only one SPS PDSCH release or HARQ-ACK information for one PDSCH reception in MA,C cases for candidate PDSCH reception, and the report is scheduled by DCI format 1_0 including information that the counter DACI field in the Pcell indicates 1, the terminal can determine one HARQ-ACK codebook for the corresponding SPS PDSCH release or the corresponding PDSCH reception.

[0539] In one embodiment, the method for determining the HARQ-ACK codebook according to the method described below is followed.

[0540] According to one embodiment, if the set of PDSCH reception candidate cases in serving cell c is MA,c, MA,c can be obtained through the following [pseudo-code 1] steps.

[0541] [Begin pseudo-code 1]

[0542] Step 1: Initialize j to 0 and MA,c to the empty set. Initialize k, the HARQ-ACK transmission timing index, to 0.

[0543] Step 2: Set R to a set of rows in a table containing slot information, start symbol information, and symbol count or length information to which the PDSCH is mapped. If the PDSCH-capable mapping symbol indicated by each value in R is set to a UL symbol according to the DL and UL settings set above, delete the corresponding row from R.

[0544] Step 3-1: If the terminal can receive one unicast PDSCH in one slot and R is not an empty set, add one to the set MA,c.

[0545] Step 3-2: If the terminal can receive more than one unicast PDSCH in one slot, count the number of PDSCHs that can be allocated to different symbols in the calculated R described above and add that number to MA,c.

[0546] Step 4: Increase k by 1 and start again from step 2.

[0547] [End of pseudo-code 1]

[0548] FIG. 19 is a diagram illustrating a process for generating a Type-1 (semi-static) HARQ-ACK codebook by a terminal according to one embodiment of the present disclosure.

[0549] According to one embodiment, taking the above-described psudo-code 1 as an example in FIG. 19, in order to perform HARQ-ACK PUCCH transmission in slot#k(1908), all slot candidates for which PDSCH-to-HARQ-ACK timing is possible and which can indicate slot#k(1908) can be considered. In FIG. 19, it can be assumed that HARQ-ACK transmission is possible in slot#k(1908) by a PDSCH-to-HARQ-ACK timing combination that is possible only for PDSCHs scheduled in slot#n(1902), slot#n+1(1904), and slot#n+2(1906). In addition, the maximum number of schedulable PDSCHs for each slot can be derived by considering the time domain resource configuration information of the PDSCHs that can be scheduled in slots 1902, 1904, and 1906, and the information indicating whether the symbol in the slot is a downlink or an uplink. For example, if two PDSCHs can be scheduled at maximum in slot 1902, three PDSCHs can be scheduled at maximum in slot 1904, and two PDSCHs can be scheduled at maximum in slot 1906, the maximum number of PDSCHs included in the HARQ-ACK codebook transmitted in slot 1908 is seven. This can be referred to as the cardinality of the HARQ-ACK codebook.

[0550] According to one embodiment, step 3-2 described above within a specific slot is described through the following [Table 44] (Default PDSCH time domain resource allocation A for normal CP).

[0551]

[0552] According to one embodiment, Table 44 is a time resource allocation table in which a terminal operates by default before receiving time resource allocation through a separate RRC signal. Note that, in addition to separately indicating the row index value to RRC, the PDSCH time resource allocation value is determined by the terminal common RRC signal dmrs-TypeA-Position. In Table 44, the ending and order columns are values ​​added separately for convenience of explanation, and may not actually exist. The meaning of the ending column refers to the end symbol of the scheduled PDSCH, and the order column may refer to a code position value located within a specific codebook in the semi-static HARQ-ACK codebook. The table is applied to the time resource allocation applied in DCI format 1_0 of the common search area of ​​the PDCCH.

[0553] According to one embodiment, the terminal may perform the following steps to determine a HARQ-ACK codebook by calculating the maximum number of non-overlapping PDSCHs within a specific slot.

[0554] Step 1: Among all rows in the PDSCH Time Resource Allocation Table, we can find the PDSCH allocation value that ends earliest within the slot. In Table 44, we can see that row index 14 ends earliest. This is marked as 1 in the order column. Furthermore, other row indices that overlap row index 14 by at least one symbol are marked as 1x in the order column.

[0555] Step 2: Then, among the remaining row indices not indicated in the Order column, the PDSCH allocation value that ends first can be searched. In Table 44, this can be the row with row index 7 and dmrs-TypeA-Position value 3. In addition, other row indices that overlap with this row index by at least one symbol are marked as 2x in the Order column.

[0556] Step 3: Repeat Step 2 and display the order value in increasing order. For example, in Table 44, the PDSCH allocation value that ends first among the row indices not indicated in the order column can be searched. In Table 44, this can be the row with row index 6 and dmrs-TypeA-Position value 3. In addition, other row indices that overlap with the row index by at least one symbol are displayed as 3x in the order column.

[0557] Step 4: If an order is displayed for all row indices, the process ends. The size of the order is the maximum number of PDSCHs that can be scheduled without time overlap within the slot. Scheduling without time overlap can mean that different PDSCHs are scheduled using TDM.

[0558] According to one embodiment, the maximum value of order in the order column of Table 44 may indicate the HARQ-ACK codebook size of the corresponding slot, and the order value may indicate the HARQ-ACK codebook point where the HARQ-ACK feedback bit for the corresponding scheduled PDSCH is located. For example, row index 16 in Table 44 may indicate that it exists at the second code position in a semi-static HARQ-ACK codebook with a size of 3. A terminal transmitting HARQ-ACK feedback may obtain MA,c by using [pseudo-code 1] or [pseudo-code 2] steps, if a set of occasions for candidates PDSCH receptions in serving cell c is MA,c. MA,c may be used to determine the number of HARQ-ACK bits to be transmitted by the terminal. Specifically, a HARQ-ACK codebook may be configured using the size (cardinality) of the MA,c set.

[0559] In one embodiment, as another example, considerations for determining a semi-static HARQ-ACK codebook (or type 1 HARQ-ACK codebook) may include:

[0560]

[0561] In one embodiment, as another example, the pseudo-code for HARQ-ACK codebook determination may be as follows.

[0562]

[0563]

[0564] According to one embodiment, the position of the HARQ-ACK codebook containing HARQ-ACK information for the DCI indicating DL SPS release in pseudo-code 2 may be based on the position at which the DL SPS PDSCH is received. For example, if the start symbol at which the DL SPS PDSCH is transmitted starts from the 4th OFDM symbol based on the slot and has a length of 5 symbols, the HARQ-ACK information including the DL SPS release indicating the release of the corresponding SPS may be determined as if a PDSCH starting from the 4th OFDM symbol of the slot in which the DL SPS release is transmitted and having a length of 5 symbols is mapped, and the corresponding HARQ-ACK information may be determined through the PDSCH-to-HARQ-ACK timing indicator and the PUSCH resource indicator included in the control information indicating the DL SPS release. As another example, if the start symbol for transmitting a DL SPS PDSCH starts from the 4th OFDM symbol based on a slot and has a length of 5 symbols, HARQ-ACK information including a DL SPS release indicating release of the corresponding SPS is assumed to be mapped to a PDSCH starting from the 4th OFDM symbol of the slot indicated by the TDRA (Time domain resource allocation) of the DCI, which is a DL SPS release, and having a length of 5 symbols, and the corresponding HARQ-ACK information can be determined through a PDSCH-to-HARQ-ACK timing indicator and a PUSCH resource indicator included in the control information indicating the DL SPS release.

[0565] [HARQ-ACK: Type 2 (dynamic) codebook related]

[0566] According to one embodiment, the terminal may transmit HARQ-ACK information to be transmitted within a PUCCH in slot n based on a PDSCH-to-HARQ_feedback timing value for PUCCH transmission of HARQ-ACK information in slot n for PDSCH reception or SPS PDSCH release and K0, which is transmission slot location information of a PDSCH scheduled in DCI format 1_0 or 1_1. Specifically, for the above-described HARQ-ACK information transmission, the terminal may determine a PDSCH-to-HARQ_feedback timing based on a DAI included in DCI indicating a PDSCH or SPS PDSCH release and a HARQ-ACK codebook of a PUCCH transmitted in a slot determined by K0.

[0567] According to one embodiment, DAI is composed of Counter DAI and Total DAI. Counter DAI is information indicating the position of HARQ-ACK information corresponding to a PDSCH scheduled in DCI format 1_0 or DCI format 1_1 within a HARQ-ACK codebook. Specifically, the value of counter DAI in DCI format 1_0 or 1_1 indicates the accumulated value of PDSCH reception or SPS PDSCH release scheduled by DCI format 1_0 or DCI format 1_1 in a specific cell c. The aforementioned accumulated value is set based on the PDCCH monitoring occasion and serving cell where the scheduled DCI exists.

[0568] In one embodiment, Total DAI is a value indicating the size of the HARQ-ACK codebook. Specifically, the value of Total DAI may indicate the total number of previously scheduled PDSCH or SPS PDSCH releases, including the time at which the DCI is scheduled. In addition, Total DAI is a parameter used when, in a CA (Carrier Aggregation) situation, HARQ-ACK information on serving cell c also includes HARQ-ACK information for PDSCHs scheduled in other cells, including serving cell c. In other words, in a system operating with a single cell, there is no Total DAI parameter.

[0569] FIG. 20 is a diagram illustrating a process for generating a Type-2 (dynamic) HARQ-ACK codebook by a terminal according to one embodiment of the present disclosure.

[0570] According to one embodiment, an operation example for DAI is shown in FIG. 20. In FIG. 20, when a terminal transmits a HARQ-ACK codebook selected based on DAI in the nth slot of carrier 0 (2002) on PUCCH (2020) in a situation where two carriers are set, the changes in the values ​​of Counter DAI (C-DAI) and Total DAI (T-DAI) indicated by the DCI searched for each PDCCH monitoring occasion set for each carrier are shown. First, the DCI searched at m=0 (2006) may indicate that C-DAI and T-DAI each have a value of 1 (2012). The DCI searched at m=1 (2008) may indicate that C-DAI and T-DAI each have a value of 2 (2014). The DCI probed on carrier 0 (c=0, 2002) of m=2 (2010) may indicate a C-DAI value of 3 (2016). The DCI probed on carrier 1 (c=1, 2004) of m=2 (2010) may indicate a C-DAI value of 4 (2018). In this case, if carriers 0 and 1 are scheduled in the same monitoring occasion, both T-DAIs are indicated as 4.

[0571] According to one embodiment, the HARQ-ACK codebook determination in FIGS. 19 and 20 operates in a situation where only one PUCCH containing HARQ-ACK information is transmitted in one slot. This can be referred to as Mode 1. As an example of a method for determining one PUCCH transmission resource in one slot, when PDSCHs scheduled in different DCIs are multiplexed and transmitted as one HARQ-ACK codebook in the same slot, the PUCCH resource selected for HARQ-ACK transmission is determined as the PUCCH resource indicated by the PUCCH resource field indicated in the DCI that last scheduled the PDSCH. That is, the PUCCH resource indicated by the PUCCH resource field indicated in the DCI scheduled before the above-described DCI is ignored.

[0572] According to one embodiment, the following description defines a method and apparatus for determining a HARQ-ACK codebook in a situation where two or more PUCCHs containing HARQ-ACK information can be transmitted within one slot. This may be referred to as Mode 2. A terminal may be able to operate only in Mode 1 (only one HARQ-ACK PUCCH is transmitted within one slot) or only in Mode 2 (one or more HARQ-ACK PUCCHs are transmitted within one slot). Alternatively, a terminal supporting both Mode 1 and Mode 2 may be configured by the base station to operate in only one mode through higher layer signaling, or Mode 1 and Mode 2 may be implicitly determined by DCI format, RNTI, DCI-specific field values, scrambling, etc. For example, a PDSCH scheduled with DCI format A and HARQ-ACK information associated therewith may be based on Mode 1, and a PDSCH scheduled with DCI format B and HARQ-ACK information associated therewith may be based on Mode 2. Whether the above-described HARQ-ACK codebook is semi-static or dynamic is determined by the RRC signal.

[0573] [Initial login related]

[0574] Below, the procedure for a terminal to initially connect to a cell is described.

[0575] Figure 21 is a diagram illustrating a procedure for transmitting and receiving data between a terminal and a base station to perform an initial connection, according to one embodiment. According to one embodiment, the role of each message (hereinafter, used interchangeably with "Msg.") is as follows.

[0576] - Msg1 (Preamble Transmission) (2105): The UE can select a random access preamble from a set of predefined preambles. These preambles can be roughly divided into two categories (short preamble and long preamble). The UE can also select a random sequence number for the preamble. After selecting the preamble and sequence number, the UE can transmit the preamble on the PRACH.

[0577] - Msg2 (e.g., Random Access Response (RAR)) (2110): Upon receiving Msg1, the gNB (5G base station) sends a response called Msg2. Msg2 consists of several important pieces of information, such as a Timing Advance (TA) command for timing adjustment, a Random Access Preamble ID (RAPID) that matches the preamble sent by the UE, and an initial uplink grant for the UE. The gNB may also assign a temporary identifier called a Random Access Radio Network Temporary Identifier (RA-RNTI) to the UE. The corresponding Msg2 information is transmitted via the PDSCH.

[0578] - Msg3 (2115): The terminal can transmit Msg3 on the PUSCH using the initial uplink grant provided in Msg2. Msg3 is a PUSCH that can carry a specific RRC message (e.g., RrcRequest) or be pure PHY data.

[0579] - Msg4 (Contention Resolution) (2120): After processing Msg3, the gNB can transmit Msg4 to the UE. Msg4 is MAC data for Contention Resolution. The Contention Resolution message contains the UE's identity, allowing the gNB to accurately identify the UE and confirm that the contention has been resolved. At this stage, the network can provide the UE with a C-RNTI (Cell Radio Network Temporary Identifier).

[0580] Afterwards, the terminal can transmit information on whether Msg4 reception was successful (or HARQ-ACK feedback) to the base station on the PUCCH. This can be referred to as the HARQ PUCCH (2125) for the Msg4 PDSCH.

[0581] Hereinafter, satellite communication features according to various embodiments of the present disclosure will be described. Satellites for communication can be classified into Low Earth Orbit (LEO), Middle Earth Orbit (MEO), and Geostationary Earth Orbit (GEO) satellites depending on their orbits. Generally, GEO refers to a satellite at an altitude of approximately 36,000 km, MEO refers to a satellite at an altitude of 5,000 to 15,000 km, and LEO refers to a satellite at an altitude of 500 to 1,000 km. Of course, according to various embodiments, these are merely examples and are not limited to the above-described examples. According to one embodiment of the present disclosure, the Earth orbital period varies depending on each altitude. For GEO, the Earth orbital period may be approximately 24 hours, for MEO, approximately 6 hours, and for LEO, approximately 90 to 120 minutes. Low Earth orbit (~2,000 km) satellites may have an advantage over geostationary orbit (36,000 km) satellites in terms of propagation delay (i.e., the time it takes for a signal transmitted from a transmitter to reach a receiver) and loss due to their relatively low altitude.

[0582] FIG. 22 is a diagram illustrating the Earth orbital period of a communication satellite according to the altitude or height of the satellite according to one embodiment of the present disclosure.

[0583] Assuming that the terminal (2210) communicates with a satellite (2220) located at an altitude of 1200 km, the distance between the terminal (2210) and the satellite (2220) may vary depending on the elevation angle between the satellite (2220) and the terminal (2210). For example, if the elevation angle between the satellite (2220) and the terminal (2210) is 90 degrees, the distance between the terminal (2210) and the satellite (2220) may be 1200 km, but if the elevation angle between the satellite (2220) and the terminal (2210) is 10 degrees, the distance between the terminal (2210) and the satellite (2220) may be approximately 3135 km. Therefore, in satellite communication, even if the terminal (2210) is fixed, the distance between the satellite (2220) and the terminal (2210) may vary over time due to the satellite orbiting periodically, such as a low-orbit satellite.

[0584] FIG. 23 illustrates a signal flow for performing an initial connection between a terminal and a base station according to one embodiment of the present disclosure.

[0585] The above-described initial connection procedure can basically operate with a single transmission. However, in cases where the distance between the transmitter and receiver is much longer than that of a terrestrial network, such as a satellite network or a non-terrestrial network (NTN), it may be difficult for the receiver to receive a signal for initial connection with only a single transmission. Therefore, as illustrated in FIG. 23, supporting repetition transmission for each of the signals (2305, 2310, 2315, 2320, 2325) for initial connection may be one method for increasing the received signal strength.

[0586] Hereinafter, according to various embodiments, the repeated transmission operations (2305, 2310, 2315, 2320, 2325) and methods for signals for initial connection are specifically described. Referring to FIG. 23, a case is illustrated in which all repeated transmissions (2305, 2310, 2315, 2320, 2325) for signals transmitted and received for initial connection between a terminal and a base station are allowed, but according to various embodiments, only at least one of these signals may be allowed to be repeatedly transmitted, and the remaining signals may include only single transmissions.

[0587] In describing the present disclosure below, upper layer signaling may include signaling corresponding to at least one or a combination of one or more of the signaling below.

[0588] MIB (Master Information Block)

[0589] System Information Block (SIB) or SIB

[0590] RRC(Radio Resource Control)

[0591] MAC (Medium Access Control) CE (Control Element)

[0592] Additionally, L1 signaling may include signaling corresponding to at least one or a combination of one or more of the signaling methods using the physical layer channels or signaling below.

[0593] Physical Downlink Control Channel (PDCCH)

[0594] Downlink Control Information (DCI)

[0595] UE-specific DCI

[0596] Group common DCI

[0597] Common DCI

[0598] Scheduling DCI (e.g., DCI used for scheduling downlink or uplink data)

[0599] Non-scheduled DCI (e.g., DCI not intended for scheduling downlink or uplink data)

[0600] Physical Uplink Control Channel (PUCCH)

[0601] Uplink Control Information (UCI)

[0602] Additionally, in various embodiments of the present disclosure, the term 'terminal' may represent any component such as 'user equipment (UE)', 'mobile station', 'subscriber station', 'remote terminal', 'wireless terminal', 'receive point', or 'user device'. For convenience, the term 'terminal' as described above may be used to represent a device that accesses a base station in various embodiments of the present disclosure, regardless of whether the terminal should be considered a mobile device (e.g., a mobile phone or a smart phone) or a fixed device (e.g., a desktop computer or a vending machine).

[0603] Additionally, in various embodiments of the present disclosure, the term 'TA (timing advance)' may be used interchangeably with 'TA information', 'TA value', or 'TA index'.

[0604] In various embodiments of the present disclosure, data or control information transmitted by a base station to a terminal may refer to a first signal, and an uplink signal associated with the first signal may refer to a second signal. For example, the first signal may include DCI, UL grant, PDCCH, PDSCH, RAR, etc., and the second signal associated with the first signal may include PUCCH, PUSCH, msg 3, etc.

[0605] Additionally, there may be an association between the first signal and the second signal. For example, if the first signal is a PDCCH including a UL grant for uplink data scheduling, the second signal corresponding to the first signal may include a PUSCH including uplink data. Meanwhile, the gap between the timings at which the first and second signals are transmitted and received may be a value predetermined between the terminal and the base station. Alternatively, the gap between the timings at which the first and second signals are transmitted and received may be determined by a value indicated by the base station or transmitted through higher-level signaling.

[0606] <Example 1: Terminal Capability Report>

[0607] During initial connection, the satellite (or base station, hereinafter, used interchangeably for convenience) may not know in advance whether the terminal is capable of repeat transmission for signals related to the initial connection. Therefore, during the initial connection process, the base station may need to receive a report of repeat transmission capability from the terminal in advance. Alternatively, even if the terminal has repeat transmission capability, it may not report the repeat transmission capability if it does not need to transmit or receive repeat transmission-based information during the initial connection. The criteria for the terminal to determine this may be based on measurements of received signal quality, such as RSRP, through SS / PBCH blocks periodically received by the terminal from the satellite. Whether the terminal should report the repeat transmission capability may be determined based on whether the measured result is greater than or less than a threshold previously set for the terminal through a higher-order signal. Furthermore, if threshold-related configuration information is not provided or a specific value is indicated, the terminal may always assume that it reports the repeat transmission capability.

[0608] According to one embodiment, a terminal may report its repetitive transmission capability to the satellite through PRACH resource selection. Specifically, when the satellite provides the terminal with information on configuring multiple PRACH resource sets in advance, the satellite may indicate that Set A is a PRACH set for terminals with repetitive transmission capability, and Set B is a PRACH set for other terminals. Accordingly, the terminal may transmit its repetitive transmission capability through PRACH resources belonging to Set A if the terminal itself has repetitive transmission capability, or if an RSRP reception signal measured through an SS / PBCH block in a situation where a threshold value is set is below a specific threshold value. Accordingly, the satellite may determine whether the terminal has repetitive transmission capability or has requested repetitive transmission through the PRACH resources selected by the terminal.

[0609] In one embodiment, a PRACH resource may include time resources, frequency resources, code resources, or a combination of some or all of these. The repetitive transmission capability reported via the PRACH resource may include at least one or a combination of two or more of the following:

[0610] - Message 2 PDSCH

[0611] - Message 3 PUSCH

[0612] - Message 4 PDSCH

[0613] - HARQ-ACK PUCCH for Message 4

[0614] - PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI

[0615] - PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI

[0616] - PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI

[0617] In one embodiment, the satellite may provide the aforementioned related configuration information together with PRACH resource information in advance. For example, the satellite may separately provide the terminal with PRACH resource information for a terminal that supports only message 3 PUSCH repeated transmission, PRACH resource information for a terminal that supports both message 2 PDSCH and message 3 PUSCH repeated transmission, etc., through upper layer signals in advance. The satellite may determine whether the terminal's repeated transmission capability is applied to a specific channel based on which PRACH resource the terminal has selected.

[0618] In one embodiment, furthermore, when the threshold values ​​described above are set, the threshold values ​​associated with message 3 PUSCH and the threshold values ​​associated with message 2 PDSCH may be the same or different.

[0619] In one embodiment, a PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI may be included in a separate terminal capability, or may be implicitly included when the terminal reports Message 3 PUSCH as a terminal capability.

[0620] In one embodiment, a PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI may be included in a separate terminal capability, or may be implicitly included when the terminal reports Message 2 PDSCH or Message 4 PDSCH as a terminal capability.

[0621] In one embodiment, a PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI may be included in a separate terminal capability, or may be implicitly included when the terminal reports a HARQ-ACK PUCCH for Message 2 PDSCH or Message 4 as a terminal capability.

[0622] In one embodiment, Message 4 PDSCH may be included as a separate terminal capability, or may be included implicitly when the terminal reports Message 2 PDSCH as a terminal capability.

[0623] According to various embodiments of the present disclosure, a terminal may report its repetitive transmission capability to a satellite via Message 3 information. According to one embodiment, Message 3 information may include at least one or a combination of two or more of the following repetitive transmission capabilities by utilizing specific bitmap information among the LCID information included in the Message 3 PUSCH transmitted by the terminal.

[0624] - Message 4 PDSCH

[0625] - HARQ-ACK PUCCH for Message 4

[0626] - PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI

[0627] - PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI

[0628] - PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI

[0629] For example, a terminal can report its repeat transmission capability by utilizing a specific codepoint or index of the LCID. If a threshold is set, the terminal can compare the RSRP strength measured through SS / PBCH reception with the threshold, and determine whether to report the terminal capability based on the comparison result.

[0630] In one embodiment, the terminal may receive related upper signal configuration information from the base station in advance (e.g., before reporting the repetitive transmission capability via message 3 information). If the base station has configured an upper signal related to the number of repetitive transmissions in relation to the repetitive transmission capability described above, the terminal may determine that the repetitive transmission capability is reported via message 3 information. Alternatively, the terminal may determine whether the repetitive transmission capability can be reported via message 3 information via separate upper signal configuration information.

[0631] According to one embodiment, the above-described 'PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI', 'PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI', or 'PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI' may each be included as a separate terminal capability, or may be implicitly transmitted together based on other capability reports performed by the terminal.

[0632] According to various embodiments of the present disclosure, a terminal may be able to support or request repeated transmission for all physical channels, regardless of whether they are PDSCH or PUSCH. The request may be transmitted to the satellite via message 1 or message 3. This allows the satellite to determine that the terminal supports or requests repeated transmission for all physical channels, regardless of whether the physical channel is distinguished. Furthermore, if the terminal is provided with separate threshold setting information, the terminal may measure the RSRP strength for SS / PBCH based on the threshold setting information, and may determine whether or not to request repeated transmission.

[0633] The terminal capability information and related operations described above (including various embodiments such as the instruction operation for repeated transmission described below) may be performed only in a non-terrestrial network, such as satellite communication. Alternatively, the terminal capability information and related operations described above may be performed only in a frequency band allocated to a non-terrestrial network. Various signaling procedures according to embodiments of the present disclosure may be performed in a band in which an NTN satellite operates. For example, in the case of FR1, an example of a dedicated operating band of an NTN base station may be as follows.

[0634]

[0635] Additionally, as a prerequisite for various signaling procedures according to embodiments of the present disclosure, the terminal may receive an SIB (e.g., SIB 19) containing information associated with NTN access from the base station. The SIB received by the terminal from the base station may include at least one of NTN configuration information associated with the terminal's satellite access, information about the time of the cell, a reference position of the cell, a distance from the reference position, or information about a neighboring cell.

[0636] However, according to various embodiments of the present disclosure, this is only an example and is not limited thereto and can be applied to a terrestrial network environment as well.

[0637] <Second Embodiment: Method for Instructing Base Station to Repeat Transmission>

[0638] According to various embodiments of the present disclosure, a base station (or satellite) may, as described above in the first embodiment, transmit to a terminal 'message 1', 'message 2', 'message 3', 'message 4', 'HARQ-ACK feedback for message 4', 'PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI', 'PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI' or 'DCI format 1_0 with CRC A repetitive transmission resource may be provided for at least one of PUCCH scheduled with scrambled by C-RNTI or CS-RNTI.

[0639] In one embodiment, the base station may provide one or more values ​​related to the repeat transmission setting values ​​for each channel via the upper signal configuration information. If one value is provided via the upper signal, the terminal may determine that the repeat transmission for the corresponding channel operates based on the value. If multiple values ​​are provided via the upper signal, the base station may indicate one of the multiple values ​​via the control information for scheduling the corresponding channel.

[0640] For example, a base station may provide DCI format 1_0 with CRC scrambled by RA-RNTI to schedule message 2 PDSCH to a terminal, and may use a repetition field consisting of one bit, two bits, or three bits in the DCI format 1_0 to indicate one of multiple repetition values ​​set as a higher-order signal.

[0641] As another example, the base station can check the Random Access Response Grant Content field size information included in the message 2 PDSCH to schedule the message 3 PUSCH, and can use the two MSBs (Most Significant Bits) of the MCS field in the information to indicate the repetition transmission value of the message 3 PUSCH.

[0642] As another example, the base station may provide DCI format 1_0 with CRC scrambled by TC-RNTI to schedule message 4 PDSCH, and may indicate repeated transmission by utilizing 1 or 2 bits of MSB (or LSB, Least Significant Bit) of DAI (Downlink assignment index) in the DCI format 1_0, or may indicate repeated transmission by utilizing 1 or 2 bits of MSB (or LSB) of MCS (or HARQ process number) field.

[0643] In one embodiment, the base station and the terminal may utilize other DCI fields.

[0644] As another example, a method for indicating the number of repetitive transmissions for a PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI may include indicating the PUSCH repetitive transmissions with one of MSB (or LSB) 1 bit, 2 bits, or 3 bits in a combination of at least one or some of a frequency resource allocation field, a time resource allocation field, a frequency hopping field, an MCS field, a new data indicator (NDI) field, a redundancy version (RV) field, a HARQ process field, or a Transmission Power Control (TPC) field.

[0645] As another example, a method for indicating the number of repetitive transmissions for a PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI may include indicating PDSCH repetitive transmissions with one of MSB (or LSB) 1 bit, 2 bits or 3 bits in a combination of at least one or some of a frequency resource allocation field, a time resource allocation field, a virtual resource block (VRB)-to-physical resource block (PRB) mapping field, an MCS field, an NDI field, an RV field, a HARQ process number field or a DAI field.

[0646] As another example, a method for indicating the number of repetitive transmissions for a PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI may include indicating the PUCCH repetitive transmissions with one of MSB (or LSB) 1 bit, 2 bits or 3 bits in a combination of at least one or some of a TPC field, a PUCCH resource field or a PDSCH-to-HARQ_feedback timing field.

[0647] In one embodiment, information about which DCI field to use to perform a repeat transmission may be determined via a separate upper signal.

[0648] According to various embodiments of the present disclosure, the terminal may determine the number of repeated transmissions at a specific point in time based on satellite position information received from a base station through an upper signal or the validity time of the information.

[0649] According to one embodiment, satellite position information may include information on how a satellite will move during a specific section in the form of ephemeris information. Specifically, the satellite position information may provide coefficient values ​​for each variable in the form of a linear function, a quadratic function, or a parabolic function. In addition, valid time information for the provided values ​​may be provided separately through an upper signal. For example, the base station may provide information on a, b, and c according to a quadratic function a(xy)^2+ b(xy)+c, and separately a reference value for y. Here, the x value may include a time value calculated by the terminal itself.

[0650] According to one embodiment, the terminal can identify the position of the satellite through the above-described information. The terminal can identify the position of the terminal through the Global Navigation Satellite System (GNSS) (e.g., a satellite navigation system) and, based on this, can identify the distance between the satellite and the terminal. Therefore, since the main cause of signal attenuation in terminal-satellite communication is path attenuation, the terminal can implicitly determine the number of repeated transmissions based on the distance between the satellite and the terminal at a specific point in time, even if separate scheduling information is not provided for at least one or more of the channels below. Alternatively, related information may be set for each of the channels below through an upper layer signal, or related information may be set through a common upper layer signal.

[0651] - Message 1 PRACH

[0652] - Message 2 PDSCH

[0653] - Message 3 PUSCH

[0654] - Message 4 PDSCH

[0655] - HARQ-ACK PUCCH for Message 4

[0656] - PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI

[0657] - PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI

[0658] - PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI

[0659] According to various embodiments of the present disclosure, in order for the terminal to implicitly determine the number of repeated transmissions, the base station may provide information such as [Table 45] below through an upper signal. For example, if the distance between the terminal and the satellite calculated by the terminal is within the range (X2~Y2), the terminal may determine the number of repeated transmissions as 2. As another example, if the distance between the terminal and the satellite calculated by the terminal is within the range (X4~Y4), the terminal may determine the number of repeated transmissions as 8. Here, Y4 may not exist or may have an infinite number. However, [Table 45] is only an example, and according to various embodiments, the repeated transmission values ​​and their specific numbers are not limited and may have various values.

[0660] In one embodiment, the minimum / maximum terminal-to-satellite distance ranges for each repeat transmission may or may not overlap. If the ranges overlap, the terminal may select one of the repeat transmission values.

[0661]

[0662] According to various embodiments of the present disclosure, although [Table 45] describes as an example a method for a terminal to determine the number of repetitive transmissions based on the distance between the terminal and the satellite, the base station may directly provide the terminal with a range in which the number of repetitive transmissions is applied for each time period through a separate upper signal setting. For example, the base station may instruct the terminal to perform repetitive transmissions 2 times in the period t1 to t2, 4 times in the period t2 to t3, or 8 times in the period t3 to t4. To this end, the base station may directly instruct the terminal through an upper signal to provide information about the time period and the number of repetitive transmissions applied by the terminal at that time. Accordingly, the terminal may perform repetitive transmissions for each channel by applying the number of repetitive transmissions set for each time period.

[0663] According to one embodiment, the information transmitted through the above-described upper signal may be included in information that the base station periodically provides common upper signal information to the terminal as SIB information. The terminal may periodically receive the SIB information and determine upper signal information commonly applied to the system. However, the terminal may not receive the periodically transmitted SIB information. In this case, the terminal may perform repeated transmission based on the SIB information received immediately before, or may perform only a single transmission without performing repeated transmission. Alternatively, the terminal may not perform any action until it acquires new SIB information. In addition, the SIB may provide configuration information that is individually applicable to the channels below, or may divide the downlink and uplink groups and provide configuration information that is commonly applicable to each group, or may divide the initial access-related channel group and other channel groups and provide configuration information that is commonly applicable to each group, or may provide configuration information that is commonly applicable to all channels regardless of the above. At this time, the information transmitted through the upper signal may include at least one of the number of repeated transmissions, valid time information, number of repeated transmission candidates, DCI field information indicating the number of repeated transmissions, or time information (or satellite information) to which the number of repeated transmissions is implicitly applied, as described above, and is not limited thereto, and may of course also include other information.

[0664] - Message 1 PRACH

[0665] - Message 2 PDSCH

[0666] - Message 3 PUSCH

[0667] - Message 4 PDSCH

[0668] - HARQ-ACK PUCCH for Message 4

[0669] - PUSCH scheduled with DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI

[0670] - PDSCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or DCI format 1_0 with CRC scrambled by SI-RNTI or DCI format 1_0 with CRC scrambled by TC-RNTI or DCI format 1_0 with CRC scrambled by RA-RNTI or CS-RNTI

[0671] - PUCCH scheduled with DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI

[0672] Figure 24 illustrates a flow of operations for a terminal to repeatedly transmit and receive signals on channels according to one embodiment of the present disclosure. Specifically, referring to Figure 24, the flow of specific operations for transmitting and receiving the terminal capability information or information regarding repeated transmission described above is illustrated.

[0673] In step (2405), the terminal can receive information related to repeated transmission from the base station through an upper signal.

[0674] In step (2410), the terminal may report the terminal capability related to repetitive transmission as described above in the first embodiment. Alternatively, the terminal may transmit a request signal to the base station requesting repetitive transmission based on a separately configured RSRP measurement signal, rather than reporting the terminal capability, if the measurement value is below a certain threshold. The above-described request may be referred to as a repetitive transmission request signal. According to one embodiment, the terminal may determine whether to transmit terminal capability information or a repetitive transmission request signal based on separate upper signal configuration information received from the base station. Alternatively, based on whether an RSRP threshold value is set, if the RSRP threshold value is set, the terminal may transmit a repetitive transmission request signal, or if the RSRP threshold value is not set, the terminal may report the terminal capability.

[0675] In step (2415), the base station may instruct the terminal via downlink control information whether to perform repeated transmission of at least one of downlink data, uplink data, or uplink control information. According to one embodiment, the base station may transmit upper signal information to the terminal to provide repeated transmission and reception of a specific channel. Specifically, the repeated transmission and reception value may include one or more values, and when multiple values ​​are set as upper signals, the terminal may explicitly identify the repeated transmission value via DCI, or implicitly identify the repeated transmission value based on the distance between the terminal and the satellite or the repeated transmission value applied at a specific time.

[0676] In step (2420), the terminal may perform repeated transmission and reception of at least one of downlink data, uplink data, or uplink control information based on the received control information. According to one embodiment, the terminal may determine whether to perform repeated transmission with respect to an initial access-related signal and at least one signal among PDSCH reception, PUSCH transmission, or PUCCH transmission based on a value set as an upper signal, and if repeated transmission is determined, repeated transmission may be performed for each channel.

[0677] <Third embodiment: Method for determining the terminal message 2 (e.g., RAR (random access response)) window>

[0678] According to various embodiments of the present disclosure, a terminal may detect DCI format 1_0 using a CRC scrambled by a corresponding RA-RNTI in a window controlled by a higher layer in response to a PRACH transmission.

[0679] In one embodiment, the above-described window may start from the first symbol of the earliest CORESET for which the terminal is configured to receive a PDCCH for a Type1-PDCCH CSS (common search space) set after the last symbol of the PRACH occasion corresponding to the PRACH transmission. At this time, the subcarrier spacing may follow the subcarriers configured in the Type1-PDCCH CSS. If the terminal obtains TA information through non-zero system information or calculates TA on its own, the window may additionally start after (TTA + Kmac) msec.

[0680] According to one embodiment, the length of the window may be provided to the terminal through separate upper signal information, ra-ResponseWindow, and the unit of ra-ResponseWindow may include a slot unit based on the subcarrier spacing for the Type1-PDCCH CSS set.

[0681] In one embodiment, if the terminal requests repeated transmission of message 2 or reports the terminal capability related thereto to the base station, and the base station schedules repeated transmission of message 2 to the terminal, the terminal may detect scheduling information within the above-described window. The scheduling information may be provided from the base station to the terminal via DCI format 1_0 with CRC scrambled by RA-RNTI. If the above-described DCI information is repeatedly transmitted, the terminal needs to clearly identify the definition of the window for detecting the above-described DCI format.

[0682] FIG. 25 illustrates a situation in which a DCI scheduling message 2 is repeatedly transmitted after transmission of a physical random access channel (PRACH) according to one embodiment of the present disclosure.

[0683] Referring to FIG. 25, according to one embodiment, a situation is illustrated in which a DCI (Msg. 2 PDCCH) scheduling message 2 is repeatedly transmitted after a terminal transmits a PRACH (e.g., Msg. 1).

[0684] In one embodiment, if, immediately after slot n in which PRACH is transmitted, the window is set to a length of interval (2504), the terminal may perform PRACH again because it did not detect a PDCCH scheduling Msg.2 during that interval.

[0685] In one embodiment, if, immediately after slot n in which PRACH is transmitted, a window is set for a period (2502), the terminal can check whether msg.2 is scheduled through the PDCCH scheduling msg.2 received at least in slot k and slot k+1. However, in this case, since the terminal does not additionally receive PDCCH information scheduling msg.2 in slot k+2 and slot k+3, the probability of successful reception performance may be reduced. Accordingly, the terminal may not receive the PDCCH providing scheduling information of msg.2 repeatedly transmitted in slot k to slot k+3. Alternatively, since at least some PDCCH resources belong to the window period (2502), the terminal can receive the PDCCH providing scheduling information of msg.2 repeatedly transmitted in slot k to slot k+3. Alternatively, the base station may perform repeated transmission of PDCCH providing scheduling information of msg.2 in slot k to slot k+3, but the terminal may only perform reception of PDCCH providing scheduling information of msg.2 transmitted only in slot k and slot k+1 belonging to the window period (2502), thereby performing control information detection. According to various embodiments of the present disclosure, FIG. 25 is merely an example, and the number of times PDCCH is repeatedly transmitted and the transmission resource region may be independently set.

[0686] In one embodiment, if, immediately after slot n in which PRACH is transmitted, a window is set to a length of interval (2500), the terminal can receive all PDCCHs scheduling msg.2 in slot k to slot k+3. Through this, the terminal can detect scheduling information of msg.2.

[0687] According to various embodiments of the present disclosure, various signal transmission and reception operations for repeated transmission between a terminal and a base station (or satellite) are disclosed. However, it should be understood that these operations may not individually be essential components. For example, various embodiments are not limited to the examples described above and may include at least one of some, all, or a combination of some of the various operations.

[0688] FIG. 26 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0689] Referring to FIG. 26, the terminal may include a transceiver, which refers to a terminal receiving unit (2600) and a terminal transmitting unit (2610), a memory (not shown), and a terminal processing unit (2605) (e.g., a terminal control unit, controller, or processor).

[0690] According to the communication method between the terminal and the base station of the various embodiments described above, the transceiver unit (2600, 2610), memory, and terminal processing unit (2605) 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, memory, and processor may be implemented in the form of a single chip.

[0691] According to one embodiment, the transceiver (2600, 2610) may transmit and receive signals with a base station. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF (radio frequency) transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and frequency-converts a received signal. However, this is only an example of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver. In addition, the transceiver may receive a signal through a wireless channel and output it to a processor, and transmit a signal output from the processor through the wireless channel.

[0692] In one embodiment, memory (not shown) may store programs and data necessary for the operation of the terminal. Furthermore, the memory may store control information or data included in signals transmitted and received by the terminal. The memory may 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 may be multiple memories.

[0693] In one embodiment, the processor may control a series of processes to enable the terminal to operate according to the embodiments described above. For example, the processor may receive a DCI consisting of two layers and control components of the terminal to simultaneously receive multiple PDSCHs. There may be multiple processors, and the processors may perform component control operations of the terminal by executing programs stored in memory.

[0694] FIG. 27 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0695] Referring to FIG. 27, the base station may include a transceiver unit, which refers to a base station receiving unit (2700) and a base station transmitting unit (2710), a memory (not shown), and a base station processing unit (2705) (e.g., a base station control unit, controller, or processor).

[0696] According to the communication method between the base station and the terminal of the various embodiments described above, the base station's transceiver units (2700, 2710), memory, and base station processing unit (2705) 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 unit, memory, and processor may be implemented in the form of a single chip.

[0697] According to one embodiment, the transceiver (2700, 2710) may transmit and receive signals with the terminal. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and frequency-converts a received signal. However, this is only an example of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver. In addition, the transceiver may receive a signal through a wireless channel, output it to a processor, and transmit the signal output from the processor through the wireless channel.

[0698] In one embodiment, memory (not shown) may store programs and data necessary for the operation of the base station. Furthermore, the memory may store control information or data included in signals transmitted and received by the base station. The memory may 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 may be multiple memories.

[0699] In one embodiment, the processor may control a series of processes so that the base station can operate according to the embodiments of the present disclosure described above. For example, the processor may 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 may perform component control operations of the base station by executing programs stored in memory.

[0700] 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.

[0701] 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 embodiments described in the claims or specification of the present disclosure.

[0702] These programs (software modules, software) may be stored in a non-volatile memory including random access memory, flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage devices, compact disc ROMs (CD-ROMs), digital versatile discs (DVDs) or other forms of optical storage devices, magnetic cassettes, or 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.

[0703] 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 implementing 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 implementing an embodiment of the present disclosure.

[0704] In the specific embodiments of the present disclosure described above, components included in the invention are expressed singularly or plurally, 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 plural may be composed of singular elements, or components expressed in singular may be composed of plural elements.

[0705] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are merely specific examples to easily explain the technical contents of the present disclosure and to help the understanding of 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, each of the embodiments described above can be combined and operated as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment can be combined 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 to operate a base station and a terminal. In addition, although the embodiments described above have been presented based on an FDD LTE system, other modifications based on the technical idea of ​​the embodiments described above can also be implemented in other systems, such as a TDD LTE system, a 5G or NR system.

[0706] 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.

[0707] 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.

[0708] 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.

[0709] Various embodiments of the present disclosure have been described above. The above 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 easily 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 below rather than the detailed description described above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present disclosure.

Claims

1. In a wireless communication system, a user equipment (UE) Transceiver; and Including a controller coupled with the above transceiver, The above controller, Transmitting to the base station first information including the capability of the terminal for repeated transmission, Receive second information from the base station instructing the repeated transmission, and Based on the second information, configured to receive one or more signals, The first information or the second information is transmitted or received in an operating band associated with non-terrestrial networks (NTN), and The above second information is received by the terminal via RRC (radio resource control) signaling or DCI (downlink control information).

2. In claim 1, the first information is transmitted based on a comparison of a threshold value and the quality of a signal received from the base station.

3. In claim 1, the first information is a terminal included in at least one of a PRACH (physical random access channel) preamble or message 3.

4. In claim 1, The second information includes non-terrestrial networks (NTN) specific information associated with the location of the base station, and A terminal, wherein the NTN specific information includes at least one of ephemeris information of the base station or information on a valid time associated with the ephemeris information.

5. In a wireless communication system, a base station, Transceiver; and Including a controller coupled with the above transceiver, The above controller, Receive first information from a user equipment (UE) including the capability of the UE for repeated transmission, Transmitting second information instructing the repeated transmission to the terminal, and Based on the second information, configured to transmit one or more signals, The first information or the second information is received or transmitted in an operating band associated with non-terrestrial networks (NTN), and The second information is transmitted by a base station via RRC (radio resource control) signaling or DCI (downlink control information).

6. In claim 5, the first information is received based on a comparison of a threshold value and the quality of a signal transmitted from the base station.

7. In claim 5, the first information is a base station included in at least one of a PRACH (physical random access channel) preamble or message 3.

8. In claim 5, The second information includes non-terrestrial networks (NTN) specific information associated with the location of the base station, and A base station, wherein the NTN specific information includes at least one of ephemeris information of the base station or information about a valid time associated with the ephemeris information.

9. In a wireless communication system, a method performed by a user equipment (UE) is as follows: A step of transmitting, to a base station, first information including the capability of the terminal regarding repeated transmission; A step of receiving second information instructing the repeated transmission from the base station; and Based on the second information, comprising a step of receiving one or more signals, The first information or the second information is transmitted or received in an operating band associated with non-terrestrial networks (NTN), and The above second information is received via RRC (radio resource control) signaling or DCI (downlink control information).

10. A method according to claim 9, wherein the first information is transmitted based on a comparison between a threshold value and the quality of a signal received from the base station.

11. A method according to claim 9, wherein the first information is included in at least one of a PRACH (physical random access channel) preamble or message 3.

12. In claim 9, The second information includes non-terrestrial networks (NTN) specific information associated with the location of the base station, and A method wherein the NTN specific information comprises at least one of ephemeris information of the base station or information about a valid time associated with the ephemeris information.

13. In a wireless communication system, a method performed by a base station, A step of receiving first information from a user equipment (UE) including the capability of the UE for repeated transmission; A step of transmitting second information instructing the repeated transmission to the terminal; and A step of transmitting one or more signals based on the second information, The first information or the second information is received or transmitted in an operating band associated with non-terrestrial networks (NTN), and The above second information is transmitted via RRC (radio resource control) signaling or DCI (downlink control information).

14. In claim 13, The first information is received based on a comparison of a threshold value and the quality of a signal transmitted from the base station, and A method in which the first information is included in at least one of a PRACH (physical random access channel) preamble or message 3.

15. In claim 13, The second information includes non-terrestrial networks (NTN) specific information associated with the location of the base station, and A method wherein the NTN specific information comprises at least one of ephemeris information of the base station or information about a valid time associated with the ephemeris information.

Images