Method and device for contention-free random access in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. A control signal processing method in a wireless communication system of the present disclosure may include the steps of: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

Description

Method and device for non-contentious random access in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a non-contention random access method for a terminal and a device capable of performing the method.

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

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

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

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

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

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

[0008] An embodiment of the present disclosure seeks to provide a device and method capable of effectively providing a service in a mobile communication system.

[0009] Embodiments of the present disclosure propose a method for non-contention random access in Subband non-overlapping full duplex (SBFD).

[0010] The disclosed embodiment provides a device and method capable of effectively providing a service in a mobile communication system.

[0011] FIG. 1 is a diagram illustrating a basic structure of a time-frequency domain in a wireless communication system according to an embodiment of the present disclosure.

[0012] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to an embodiment of the present disclosure.

[0013] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to an embodiment of the present disclosure.

[0014] FIG. 4 is a diagram illustrating an example of setting a control region of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.

[0015] FIG. 5 is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.

[0016] FIG. 6 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 an embodiment of the present disclosure.

[0017] FIG. 7 is a diagram illustrating an example of frequency axis resource allocation of PDSCH in a wireless communication system according to an embodiment of the present disclosure.

[0018] FIG. 8 is a diagram illustrating an example of time axis resource allocation of PDSCH in a wireless communication system according to an embodiment of the present disclosure.

[0019] FIG. 9 is a diagram illustrating an example of time axis resource allocation according to subcarrier spacing of a data channel and a control channel in a wireless communication system according to an embodiment of the present disclosure.

[0020] FIG. 10 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 an embodiment of the present disclosure.

[0021] FIG. 11 is a diagram illustrating a random access procedure in one embodiment of the present disclosure.

[0022] FIG. 12 is a diagram illustrating an example of SBFD operation in a TDD band of a wireless communication system according to one embodiment of the present disclosure.

[0023] FIG. 13 is a diagram illustrating valid RACH opportunities in a TDD configuration and an SBFD configuration according to an embodiment of the present disclosure.

[0024] FIG. 14 is a diagram illustrating an index of a valid RACH opportunity in a TDD configuration and an SBFD configuration according to an embodiment of the present disclosure.

[0025] FIG. 15 is a flowchart illustrating the operation of a terminal according to an embodiment of the present disclosure.

[0026] FIG. 16 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0027] FIG. 17 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0028] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0029] 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 convey the gist of the present disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0030] 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.

[0031] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, a detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and may vary depending on the intention or custom of the user or operator. Therefore, their definitions should be made based on the contents throughout the specification.

[0032] Hereinafter, the base station is an entity that performs resource allocation of the terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although the LTE or LTE-A system may be described below as an example, the embodiments of the present disclosure may also be applied to other communication systems having a similar technical background or channel type. For example, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included here, and the 5G below may also be a concept that includes existing LTE, LTE-A, and other similar services. In addition, the present disclosure may be applied to other communication systems with some modifications within a scope that does not significantly deviate from the scope of the present disclosure, as judged by a person having skilled technical knowledge.

[0033] 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).

[0034] 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.

[0035] Here, the term '~ part' used in the present embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium or may be configured to play one or more processors. Therefore, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ parts' may be combined into a smaller number of components and '~ parts' or further separated into additional components and '~ parts'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~part' may include one or more processors.

[0036] 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.

[0037] As a representative example of the above broadband wireless communication system, the LTE system adopts the OFDM (Orthogonal Frequency Division Multiplexing) method in the downlink (DL) and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method in the uplink (UL). The uplink refers to a wireless link in which a terminal (User Equipment (UE) or Mobile Station (MS)) transmits data or control signals to a base station (eNode B or base station (BS)), and the downlink refers to a wireless link in which a base station transmits data or control signals to a terminal. The above multiple access method can distinguish the data or control information of each user by allocating and operating the time-frequency resources for transmitting data or control information to each user so that they do not overlap, that is, so as to achieve orthogonality.

[0038] As a future communications system beyond LTE, 5G communication systems must be able to freely reflect the diverse needs of users and service providers. Therefore, they must support services that simultaneously satisfy these diverse requirements. Services being considered for 5G communication systems include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC).

[0039] eMBB aims to provide data transmission rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to support a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink from the perspective of a single base station. Furthermore, 5G communication systems must simultaneously provide the peak data rate and an increased user-perceived data rate for terminals. To meet these requirements, improvements in various transmission and reception technologies, including improved multi-input, multi-output (MIMO) transmission technology, are required. Furthermore, while LTE transmits signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the data transmission rates required by 5G communication systems by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher 6 GHz band.

[0040] 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.

[0041] Finally, URLLC refers to a cellular-based wireless communication service used for a specific purpose (mission-critical). For example, services such as remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, and emergency alerts can be considered. Therefore, the communication provided by URLLC must provide very low latency and very high reliability. For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds and, at the same time, must have a 10 -5The following packet error rate (PER) requirements apply. Therefore, for services supporting URLLC, 5G systems must provide a smaller Transmit Time Interval (TTI) than other services. Simultaneously, design considerations may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0042] 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.

[0043] [NR time-frequency resources]

[0044] Below, the frame structure of the 5G system is described in more detail with reference to drawings.

[0045] FIG. 1 is a diagram illustrating the basic structure of a time-frequency domain, which is a wireless resource domain in which data or control channels are transmitted, in a 5G system according to an embodiment of the present disclosure.

[0046] The horizontal axis of Figure 1 represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time and frequency domains is a resource element (RE, 101), which can be defined as 1 OFDM (Orthogonal Frequency Division Multiplexing) symbol (102) on the time axis and 1 subcarrier (103) on the frequency axis. In the frequency domain (For example, 12) consecutive REs can form one resource block (RB, 104).

[0047] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to an embodiment of the present disclosure.

[0048] Figure 2 illustrates an example of a structure of a frame (Frame, 200), a subframe (Subframe, 201), and a slot (Slot, 202). One frame (200) can be defined as 10 ms. One subframe (201) can be defined as 1 ms, and therefore one frame (200) can be composed of a total of 10 subframes (201). One slot (202, 203) can be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( )=14).1 A subframe (201) may be composed of one or more slots (202, 203), and the number of slots (202, 203) per subframe (201) may vary depending on the setting value μ (204, 205) for the subcarrier spacing. In an example of FIG. 2, 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, depending on the setting value μ for the subcarrier spacing, the number of slots per 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.

[0049] [Table 1]

[0050]

[0051] [Bandwidth Part (BWP)]

[0052] Next, the bandwidth part (BWP) setting in the 5G communication system will be explained in detail with reference to the drawing.

[0053] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to an embodiment of the present disclosure.

[0054] Figure 3 shows an example in which the UE bandwidth (300) is set to two bandwidth portions, namely, bandwidth portion #1 (BWP#1) (301) and bandwidth portion #2 (BWP#2) (302). The base station can set one or more bandwidth portions to the UE, and can set information such as Table 2 below for each bandwidth portion.

[0055] [Table 2]

[0056]

[0057] Of course, the above example is not limited, and in addition to the above configuration information, various parameters related to the bandwidth portion can be configured for the terminal. The above information can be transmitted from the base station to the terminal via upper layer signaling, for example, RRC (Radio Resource Control) signaling. At least one bandwidth portion among the configured one or more bandwidth portions can be activated. Whether or not the configured bandwidth portion is activated can be semi-statically transmitted from the base station to the terminal via RRC signaling or dynamically transmitted via DCI (Downlink Control Information).

[0058] According to some embodiments, a terminal before RRC (Radio Resource Control) connection can receive the initial bandwidth portion (Initial BWP) for initial connection from the base station through MIB (Master Information Block). More specifically, during the initial connection phase, the terminal can receive configuration information about 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 connection can be transmitted through MIB. 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 MIB. In addition, the base station can notify the terminal of configuration information about the monitoring cycle and occasion for control region #0, i.e., configuration information for search space #0, through 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.

[0059] The settings for the bandwidth supported by the above 5G can be used for various purposes.

[0060] In some embodiments, when the bandwidth supported by a terminal is smaller than the system bandwidth, this can be supported through bandwidth portion configuration. For example, the base station can configure the bandwidth portion frequency location (configuration information 2) for the terminal, thereby allowing the terminal to transmit and receive data at a specific frequency location within the system bandwidth.

[0061] 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.

[0062] Furthermore, in some embodiments, the base station may configure bandwidth portions with different bandwidth sizes for the terminal to reduce power consumption. For example, if the terminal supports a very large bandwidth, such as 100 MHz, and constantly transmits and receives data using that bandwidth, this may result in very high power consumption. In particular, monitoring unnecessary downlink control channels using a large bandwidth of 100 MHz in a traffic-free environment may be very inefficient in terms of power consumption. To reduce power consumption, the base station may configure a bandwidth portion with a relatively small bandwidth, such as 20 MHz, for the terminal. In a traffic-free environment, the terminal may perform monitoring operations in the 20 MHz bandwidth portion, and when data is generated, it may transmit and receive data using the 100 MHz bandwidth portion according to the instructions of the base station.

[0063] In the method for setting the bandwidth part, terminals before RRC connection (Connected) can receive setting information for the initial bandwidth part through the MIB (Master Information Block) in the initial access stage. More specifically, the terminal can set a control region (Control Resource Set, CORESET) for a downlink control channel on which DCI (Downlink Control Information) for scheduling 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 the purpose of receiving the SIB, the initial bandwidth part can also be utilized for other system information (Other System Information, OSI), paging, and random access.

[0064] [Change in bandwidth part (BWP)]

[0065] When one or more bandwidth parts are set for a terminal, the base station can instruct the terminal to change (or switch, transition) the bandwidth part using the bandwidth part indicator field in the DCI. For example, in FIG. 3, when the currently activated bandwidth part of the terminal is bandwidth part #1 (301), the base station can instruct the terminal to bandwidth part #2 (302) using the bandwidth part indicator in the DCI, and the terminal can perform a bandwidth part change to bandwidth part #2 (302) indicated by the bandwidth part indicator in the received DCI.

[0066] As described above, since DCI-based bandwidth part change can be indicated by DCI scheduling PDSCH or PUSCH, when a terminal receives a bandwidth part change request, it must be able to receive or transmit PDSCH or PUSCH scheduled by the corresponding DCI without difficulty in the changed bandwidth part. To this end, the standard stipulates the delay time (T) required when changing the bandwidth part. BWP ) and can be defined as in Table 3, for example.

[0067] [Table 3]

[0068]

[0069] The bandwidth-partial change delay time requirement supports Type 1 or Type 2 depending on the terminal's capability. The terminal can report the supported bandwidth-partial delay time type to the base station.

[0070] According to the requirement for bandwidth part change delay time mentioned above, when the terminal receives DCI including bandwidth part change indicator in slot n, the terminal changes to the new bandwidth part indicated by the bandwidth part change indicator in slot n+T. BWP The completion can be done at a later time, and transmission and reception for the data channel scheduled by the DCI can be performed in the new bandwidth portion that has been changed. When the base station wants to schedule a data channel in the new bandwidth portion, the terminal's bandwidth portion change delay time (T BWP ), time domain resource allocation for the data channel can be determined. That is, when the base station schedules the data channel with a new bandwidth portion, the data channel can be scheduled after the bandwidth portion change delay time in the method of determining the time domain resource allocation for the data channel. Accordingly, the terminal can determine whether the DCI instructing the bandwidth portion change is after the bandwidth portion change delay time (TBWP ) may not be expected to indicate a slot offset (K0 or K2) value smaller than that.

[0071] If the terminal receives DCI (e.g., DCI format 1_1 or 0_1) indicating a bandwidth change, the terminal may not perform any transmission or reception during the time period from the third symbol of the slot in which the PDCCH including the DCI is received to the start point of the slot indicated by the slot offset (K0 or K2) value indicated by the time domain resource allocation indicator field in the DCI. For example, if the terminal receives DCI indicating a bandwidth change in slot n and the slot offset value indicated by the DCI is K, the terminal may not perform any transmission or reception from the third symbol of slot n to the symbol before slot n+K (i.e., the last symbol of slot n+K-1).

[0072] [SS / PBCH block]

[0073] Next, we will explain the SS (Synchronization Signal) / PBCH block in 5G.

[0074] An SS / PBCH block may refer to a physical layer channel block consisting of a PSS (Primary SS), SSS (Secondary SS), and PBCH. Specifically, it is as follows.

[0075] - PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides some information about the cell ID.

[0076] - SSS: It serves as a reference for downlink time / frequency synchronization and provides the remaining cell ID information not provided by PSS. Additionally, it can serve as a reference signal for PBCH demodulation.

[0077] - PBCH: Provides essential system information required for the terminal's data channel and control channel transmission and reception. Essential system information may include search space-related control information indicating radio resource mapping information for the control channel, and scheduling control information for a separate data channel that transmits system information.

[0078] - 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.

[0079] The terminal can detect PSS and SSS in the initial access stage, and decode PBCH. The terminal can obtain MIB from PBCH, and can set control region (Control Resource Set; CORESET) #0 (which may correspond to a control region with a control region index of 0) therefrom. The terminal can monitor control region #0, assuming that the selected SS / PBCH block and the DMRS (Demodulation Reference Signal) transmitted in control region #0 are QCL (Quasi Co Location). The terminal can receive system information through downlink control information transmitted in control region #0. The terminal can obtain RACH (Random Access Channel) related configuration information required for initial access from the received system information. The terminal can transmit PRACH (Physical RACH) to the base station considering the selected SS / PBCH index, and the base station receiving the PRACH can obtain information on the SS / PBCH block index selected by the terminal. The base station can know that the terminal has selected a block among each SS / PBCH block and monitors the control region #0 associated with it.

[0080] [PDCCH: DCI related]

[0081] Next, we will specifically explain downlink control information (DCI) in the 5G system.

[0082] 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.

[0083] DCI can be transmitted over the Physical Downlink Control Channel (PDCCH) after going through the channel coding and modulation process. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC can be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs can be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly, but is included in the CRC calculation process. When the UE receives a DCI message transmitted on the PDCCH, it verifies the CRC using the assigned RNTI. If the CRC verification result is correct, the UE can determine that the message was transmitted to the UE.

[0084] 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).

[0085] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_0 with the CRC scrambled with C-RNTI can include, for example, the information in Table 4.

[0086] [Table 4]

[0087]

[0088] DCI format 0_1 ​​can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_1 ​​with the CRC scrambled with C-RNTI can include, for example, the information in Table 5.

[0089] [Table 5]

[0090]

[0091]

[0092] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_0 with the CRC scrambled with C-RNTI can include, for example, the information in Table 6.

[0093] [Table 6]

[0094]

[0095] DCI format 1_1 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_1 with the CRC scrambled with C-RNTI can include, for example, the information in Table 7.

[0096] [Table 7]

[0097]

[0098] [PDCCH: CORESET, REG, CCE, Search Space]

[0099] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0100] 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 according to an embodiment of the present disclosure. 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.

[0101] In the aforementioned 5G, the control region can be established by the base station to the terminal via higher-layer signaling (e.g., system information, Master Information Block (MIB), Radio Resource Control (RRC) signaling). Establishing a control region for the terminal means providing information such as the control region identifier, the frequency location of the control region, and the symbol length of the control region. For example, this information may include the information in Table 8.

[0102] [Table 8]

[0103]

[0104] In Table 8, the tci-StatesPDCCH (simply named TCI (Transmission Configuration Indication) state) configuration information may include information on one or more SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) block indices or CSI-RS (Channel State Information Reference Signal) indices that are in a QCL (Quasi Co Located) relationship with the DMRS transmitted in the corresponding control region.

[0105] FIG. 5 is a diagram showing an example of a basic unit of time and frequency resources that constitute a downlink control channel that can be used in 5G according to an embodiment of the present disclosure. According to FIG. 5, the basic unit of time and frequency resources that constitute a control channel can be referred to as a REG (Resource Element Group, 503), and a REG (503) can be defined as 1 OFDM symbol (501) on the time axis and 1 PRB (Physical Resource Block, 502) on the frequency axis, i.e., 12 subcarriers. A base station can concatenate REGs (503) to constitute a downlink control channel allocation unit.

[0106] As illustrated in FIG. 5, if the basic unit to which a downlink control channel is allocated in 5G is called a CCE (Control Channel Element, 504), 1 CCE (504) can be composed of multiple REGs (503). Taking the REG (503) illustrated in FIG. 5 as an example, the REG (503) can be composed of 12 REs, and if 1 CCE (504) is composed of 6 REGs (503), 1 CCE (504) can be composed of 72 REs. When a downlink control region is set, the region can be composed of multiple CCEs (504), and a specific downlink control channel can be mapped to one or multiple CCEs (504) and transmitted according to the aggregation level (AL) within the control region. CCEs (504) within the control area are distinguished by numbers, and the numbers of the CCEs (504) can be assigned according to a logical mapping method.

[0107] The basic unit of the downlink control channel illustrated in FIG. 5, that is, the REG (503), may include both the REs to which the DCI is mapped and the areas to which the DMRS (505), which is a reference signal for decoding the REs, is mapped. As shown in FIG. 5, three DMRSs (505) may be transmitted within one REG (503). The number of CCEs required to transmit the PDCCH may be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and different numbers of CCEs may be used to implement link adaptation of the downlink control channel. For example, when the aggregation level AL = L, one downlink control channel may be transmitted through L CCEs. The terminal must detect a signal without knowing information about the downlink control channel, and a search space representing a set of CCEs is defined for blind decoding. A search space is a set of downlink control channel candidates (CCEs) that a terminal must attempt to decode at a given aggregation level. Since there are multiple aggregation levels, each of which can be a set of 1, 2, 4, 8, or 16 CCEs, a terminal can have multiple search spaces. A search space set can be defined as the set of search spaces at all configured aggregation levels.

[0108] Search spaces can be categorized into common search spaces and UE-specific search spaces. A certain group of UEs, or all UEs, can search the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling of system information or paging messages. For example, PDSCH scheduling allocation information for transmitting SIBs, including cell operator information, can be received by searching the common search space of the PDCCH. In the case of the common search space, since a certain group of UEs, or all UEs, must receive the PDCCH, it can be defined as a set of pre-arranged CCEs. Scheduling allocation information for UE-specific PDSCH or PUSCH can be received by searching the UE-specific search space of the PDCCH. The UE-specific search space can be defined UE-specifically as a function of the UE's identity and various system parameters.

[0109] In 5G, parameters for the search space for PDCCH can be configured from the base station to the terminal via higher-layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station can configure the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the monitoring occasion for each symbol within the slot for the search space, the search space type (common search space or terminal-specific search space), the combination of DCI format and RNTI to be monitored in the corresponding search space, the control region index to be monitored for the search space, etc. to the terminal. For example, the information in Table 9 can be included.

[0110] [Table 9]

[0111]

[0112]

[0113] Depending on the configuration information, the base station may configure one or more search space sets for the terminal. In some embodiments, the base station may configure search space set 1 and search space set 2 for the terminal, and 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.

[0114] According to the configuration information, one or more search space sets may exist in a common search space or a terminal-specific search space. For example, search space set #1 and search space set #2 may be configured as a common search space, and search space set #3 and search space set #4 may be configured as terminal-specific search spaces.

[0115] In the common search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these.

[0116] - 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

[0117] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0118] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0119] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0120] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0121] In a terminal-specific search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these examples.

[0122] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0123] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0124] The RNTIs specified may follow the definitions and uses below.

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

[0126] - TC-RNTI (Temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes.

[0127] - CS-RNTI (Configured Scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0128] - RA-RNTI (Random Access RNTI): Used for PDSCH scheduling in the random access phase.

[0129] - P-RNTI (Paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0130] - SI-RNTI (System Information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0131] - INT-RNTI (Interruption RNTI): Used to indicate whether puncturing is occurring on the PDSCH.

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

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

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

[0135] The aforementioned specified DCI formats may follow definitions such as the examples in Table 10.

[0136] [Table 10]

[0137]

[0138] In 5G, the search space of aggregation level L in the control region p and search space set s can be expressed as in the following mathematical expression 1.

[0139] [Mathematical Formula 1]

[0140]

[0141] - : Integration level

[0142] - Carrier Index

[0143] - Total number of CCEs existing within the control region p

[0144] - Slot Index

[0145] - Number of PDCCH candidates for aggregation level L

[0146] - PDCCH candidate index for aggregation level L

[0147] -

[0148] -

[0149] - Terminal identifier

[0150] The value can be 0 for a common search space.

[0151] 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.

[0152] In 5G, since multiple search space sets can be configured with different parameters (e.g., parameters in Table 9), the set of search space sets monitored by a terminal at each point in time can be different. For example, if search space set #1 is configured with an X-slot period and search space set #2 is configured with a Y-slot period and X and Y are different, the terminal can monitor both search space set #1 and search space set #2 in a specific slot, or can monitor either search space set #1 or search space set #2 in a specific slot.

[0153] FIG. 6 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 an embodiment of the present disclosure.

[0154] Referring to FIG. 6, a downlink data channel (PDSCH) (601) and a rate matching resource (602) are illustrated. A base station can configure one or more rate matching resources (602) to a terminal through upper layer signaling (e.g., RRC signaling). Rate matching resource (602) configuration information can include time-domain resource allocation information (603), frequency-domain resource allocation information (604), and period information (605). Hereinafter, a bitmap corresponding to frequency-domain resource allocation information (604) may be referred to as a “first bitmap,” a bitmap corresponding to time-domain resource allocation information (603) may be referred to as a “second bitmap,” and a bitmap corresponding to period information (605) may be referred to as a “third bitmap.” If all or part of the time and frequency resources of the scheduled data channel (601) overlap with the set rate matching resources (602), the base station can rate-match and transmit the data channel (601) in the rate matching resource (602) portion, and the terminal can perform reception and decoding after assuming that the data channel (601) is rate-matched in the rate matching resource (602) portion.

[0155] [PDSCH: Frequency Resource Allocation Related]

[0156] FIG. 7 is a diagram illustrating an example of frequency-axis resource allocation of a PDSCH (physical downlink shared channel) in a wireless communication system according to an embodiment of the present disclosure.

[0157] FIG. 7 is a diagram illustrating three frequency axis resource allocation methods, type 0 (700), type 1 (705), and dynamic switch (710), which can be set via an upper layer in an NR wireless communication system.

[0158] Referring to Fig. 7, if a terminal is set to use only resource type 0 through upper layer signaling (700), some downlink control information (DCI) that allocates PDSCH to the terminal includes a bitmap consisting of NRBG bits. The conditions for this will be explained later. At this time, NRBG means the number of RBGs (resource block groups) determined as shown in [Table 11] below according to the BWP size allocated by the BWP indicator and the upper layer parameter rbg-Size, and data is transmitted to the RBG indicated as 1 by the bitmap.

[0159] [Table 11]

[0160]

[0161] If the terminal is configured to use only resource type 1 through upper layer signaling (705), some DCIs that allocate PDSCH to the terminal It includes frequency axis resource allocation information consisting of bits. The conditions for this will be explained later. Through this, the base station can set the starting VRB (720) and the length (725) of frequency axis resources allocated continuously therefrom.

[0162] If a terminal is configured to use both resource type 0 and resource type 1 through upper layer signaling (710), some DCIs that allocate PDSCH to the terminal include frequency-axis resource allocation information composed of bits of a larger value (735) among the payload (715) for configuring resource type 0 and the payload (720, 725) for configuring resource type 1. Conditions for this will be explained later. At this time, one bit may be added to the first part (MSB) of the frequency-axis resource allocation information in the DCI, and if the bit has a value of '0', it may indicate that resource type 0 is used, and if the bit has a value of '1', it may indicate that resource type 1 is used.

[0163] [PDSCH / PUSCH: Time Resource Allocation Related]

[0164] Below, a time domain resource allocation method for data channels in next-generation mobile communication systems (5G or NR systems) is described.

[0165] A base station can set up a table for time domain resource allocation information for a downlink data channel (Physical Downlink Shared Channel, PDSCH) and an uplink data channel (Physical Uplink Shared Channel, PUSCH) to a terminal through higher layer signaling (e.g., RRC signaling). A table with up to maxNrofDL-Allocations=16 entries can be set up for PDSCH, and a table with up to maxNrofUL-Allocations=16 entries can be set up for PUSCH. In one embodiment, the time domain resource allocation information may include PDCCH-to-PDSCH slot timing (corresponding to the time interval in slot units between the time point of receiving a PDCCH and the time point of transmitting a PDSCH scheduled by the received PDCCH, denoted as K0), PDCCH-to-PUSCH slot timing (corresponding to the time interval in slot units between the time point of receiving a PDCCH and the time point of transmitting a PUSCH scheduled by the received PDCCH, denoted as K2), information on the position and length of the start symbol for which a PDSCH or PUSCH is scheduled within a slot, a mapping type of the PDSCH or PUSCH, etc. For example, information such as [Table 12] or [Table 13] below may be transmitted from the base station to the terminal.

[0166] [Table 12]

[0167]

[0168] [Table 13]

[0169]

[0170] The base station may notify the terminal of one of the entries in the table for the time domain resource allocation information described above via L1 signaling (e.g., DCI) (e.g., indicated by the 'Time Domain Resource Allocation' field in the DCI). The terminal may obtain the time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

[0171] FIG. 8 is a diagram illustrating an example of time axis resource allocation of PDSCH in a wireless communication system according to an embodiment of the present disclosure.

[0172] Referring to FIG. 8, the base station uses the upper layer to set the subcarrier spacing (SCS) (μ) of the data channel and the control channel. PDSCH , μ PDCCH ), scheduling offset (K0) value, and the time axis position of the PDSCH resource can be indicated according to the OFDM symbol start position (800) and length (805) within a slot (810) dynamically indicated through DCI.

[0173] FIG. 9 is a diagram illustrating an example of time-domain resource allocation according to subcarrier spacing of a data channel and a control channel in a wireless communication system according to an embodiment of the present disclosure.

[0174] Referring to Fig. 9, when the subcarrier spacing of the data channel and the control channel is the same (900, μ PDSCH = μ PDCCH), since the slot numbers for data and control are the same, the base station and the terminal can generate a scheduling offset according to the predetermined slot offset K0. On the other hand, if the subcarrier spacing of the data channel and the control channel are different (905, μ PDSCH ≠ μ PDCCH ), since the slot numbers for data and control are different, the base station and the terminal can generate a scheduling offset according to a predetermined slot offset K0 based on the subcarrier interval of the PDCCH.

[0175] [PUSCH: Transmission Method Related]

[0176] Below, the scheduling method for PUSCH transmission is described. PUSCH transmission can be dynamically scheduled by the UL grant in the DCI or can operate by configured grant Type 1 or Type 2. Dynamic scheduling instructions for PUSCH transmission can be made in DCI format 0_0 or 0_1.

[0177] In one example, a Configured grant Type 1 PUSCH transmission can be semi-statically configured by receiving a configuredGrantConfig containing the rrc-ConfiguredUplinkGrant of [Table 14] 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 the UL grant in the DCI after receiving a configuredGrantConfig not containing the rrc-ConfiguredUplinkGrant of [Table 14] via higher-order signaling. When a PUSCH transmission operates by the configured grant, the parameters applied to the PUSCH transmission can be applied by the configuredGrantConfig of the higher-order signaling of [Table 14], except for dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and scaling of UCI-OnPUSCH provided by the pusch-Config of the higher-order signaling of [Table 15]. If the terminal has been provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 14], the terminal can apply tp-pi2BPSK in pusch-Config of [Table 15] to PUSCH transmission operated by configured grant.

[0178] [Table 14]

[0179]

[0180]

[0181] Next, the PUSCH transmission method is described. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission can follow a codebook-based or non-codebook-based transmission method, respectively, depending on whether the value of txConfig in the upper signaling, pusch-Config in [Table 15], is 'codebook' or 'nonCodebook'.

[0182] As described above, PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, and can be semi-statically configured by configured grant. If the UE is instructed to schedule PUSCH transmission via DCI format 0_0, the UE performs beam configuration for PUSCH transmission using pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the activated uplink BWP within the serving cell, and the PUSCH transmission is based on a single antenna port. The UE does not expect scheduling for PUSCH transmission via DCI format 0_0 within a BWP where a PUCCH resource including pucch-spatialRelationInfo is not configured. If the UE does not configure txConfig in pusch-Config of [Table 15], the UE does not expect to be scheduled with DCI format 0_1.

[0183] [Table 15]

[0184]

[0185]

[0186] Next, we describe codebook-based PUSCH transmission. 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. When codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or semi-statically configured via a configured grant, the UE determines a precoder for PUSCH transmission based on the SRS Resource Indicator (SRI), Transmission Precoding Matrix Indicator (TPMI), and transmission rank (the number of PUSCH transmission layers).

[0187] At this time, the SRI can be given through the SRS resource indicator field in the DCI or configured through the srs-ResourceIndicator higher-level signaling. The UE is configured with at least one SRS resource when transmitting a codebook-based PUSCH, and can be configured with up to two. When the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. In addition, the TPMI and transmission rank can be given through the precoding information and number of layers fields in the DCI or configured through the precodingAndNumberOfLayers higher-level signaling. The TPMI is used to indicate the precoder applied to the PUSCH transmission. If the UE is configured with one SRS resource, the TPMI is used to indicate the precoder to be applied to the configured one SRS resource. When a terminal is configured with multiple SRS resources, TPMI is used to indicate the precoder to be applied in the SRS resource indicated through SRI.

[0188] The precoder to be used for PUSCH transmission is selected from an uplink codebook having the same number of antenna ports as the nrofSRS-Ports value in the upper layer signaling, SRS-Config. In codebook-based PUSCH transmission, the UE determines the codebook subset based on the TPMI and codebookSubset in the upper layer signaling, pusch-Config. The codebookSubset in the upper layer signaling, pusch-Config, can be set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability reported by the UE to the base station. If the UE reported 'partialAndNonCoherent' as the UE capability, the UE does not expect the value of codebookSubset in the upper layer signaling to be set to 'fullyAndPartialAndNonCoherent'. Additionally, if the UE reports 'nonCoherent' as the UE capability, the UE does not expect the value of the upper signaling codebookSubset to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. If nrofSRS-Ports in the upper signaling SRS-ResourceSet points to two SRS antenna ports, the UE may not expect the value of the upper signaling codebookSubset to be set to 'partialAndNonCoherent'.

[0189] A terminal can be configured with one SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', and one SRS resource within the SRS resource set can be indicated via SRI. If multiple SRS resources are configured in an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', the terminal can expect that the value of nrofSRS-Ports in the upper signaling SRS-Resource is set to the same value for all SRS resources.

[0190] The terminal transmits one or more SRS resources included in an SRS resource set in which the usage value is set to 'codebook' according to upper signaling to the base station, and the base station can select one of the SRS resources transmitted by the terminal and instruct 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 information indicating a TPMI and rank to be used by the terminal for PUSCH transmission in the DCI. 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.

[0191] 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.

[0192] In one example, for an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'nonCodebook', the UE may be configured with one connected NZP CSI-RS resource (non-zero power CSI-RS). The UE 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 UE is less than 42 symbols, the UE may not expect that information for the precoder for SRS transmission is updated.

[0193] In one example, 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 may be 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 must 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 may not be set to QCL-TypeD.

[0194] If a periodic or semi-persistent SRS resource set is configured, the associated NZP CSI-RS can be indicated through the associatedCSI-RS within the upper-level signaling SRS-ResourceSet. For non-codebook-based transmission, the UE does not expect the upper-level signaling spatialRelationInfo for the SRS resource and the associatedCSI-RS within the upper-level signaling SRS-ResourceSet to be configured together.

[0195] When multiple SRS resources are configured, the UE can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. At this time, the SRI can be indicated through the SRS resource indicator field in the DCI or set through the upper signaling srs-ResourceIndicator. Similar to the codebook-based PUSCH transmission described above, when the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI.

[0196] A UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be simultaneously transmitted in the same symbol within one SRS resource set and the maximum number of SRS resources can be determined by the UE capability that the UE reports to the base station. At this time, SRS resources that the UE transmits simultaneously occupy the same RB. The UE can configure one SRS port for each SRS resource. Only one SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'nonCodebook' can be configured, and up to four SRS resources for non-codebook based PUSCH transmission can be configured.

[0197] The base station transmits one NZP-CSI-RS associated with an SRS resource set to the 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 the result measured upon reception of the NZP-CSI-RS. When the terminal transmits one or more SRS resources within the SRS resource set in which usage is set to 'nonCodebook' to the base station, the terminal applies the calculated precoder, 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 transmits the PUSCH by applying the precoder applied to SRS resource transmission to each layer.

[0198] [CA / DC related]

[0199] FIG. 10 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation according to an embodiment of the present disclosure.

[0200] Referring to FIG. 10, the wireless protocol of the next-generation mobile communication system is composed of NR SDAP (Service Data Adaptation Protocol 1025, 1070), NR PDCP (Packet Data Convergence Protocol 1030, 1065), NR RLC (Radio Link Control 1035, 1060), and NR MAC (Medium Access Control 1040, 1055) in the terminal and NR base station, respectively.

[0201] In one example, the main functions of NR SDAP (1025, 1070) may include some of the following functions:

[0202] - Transfer of user plane data

[0203] - Mapping function between QoS flow and data bearer for both DL and UL

[0204] - Marking function of QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0205] - Ability to map reflective QoS flow to data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0206] 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. In one example, when the SDAP header is configured, a 1-bit indicator for NAS QoS reflection configuration (NAS reflective QoS) and a 1-bit indicator for AS QoS reflection configuration (AS reflective QoS) in the SDAP header can be configured to instruct the terminal to update or reset mapping information for QoS flows and data bearers of the uplink and downlink. The SDAP header can include QoS flow ID information indicating QoS. The QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

[0207] The main functions of NR PDCP (1030, 1065) may include some of the following functions:

[0208] - Header compression and decompression (ROHC only)

[0209] - User data transfer function

[0210] - In-sequence delivery of upper layer PDUs

[0211] - Out-of-sequence delivery of upper layer PDUs

[0212] - PDCP PDU reordering for reception

[0213] - Duplicate detection of lower layer SDUs

[0214] - Retransmission function (Retransmission of PDCP SDUs)

[0215] - Encryption and decryption functions (Ciphering and deciphering)

[0216] - Timer-based SDU discard in uplink.

[0217] In one example, the reordering function of an NR PDCP device may include a function to reorder PDCP PDUs received from a lower layer in order based on a PDCP SN (sequence number), and may include a function to transmit data to an upper layer in the reordered order. Alternatively, the reordering function of an NR PDCP device may include a function to directly transmit data without considering the order, and may include a function to record lost PDCP PDUs by reordering the order. In addition, the reordering function of an NR PDCP device may include a function to report a status on lost PDCP PDUs to the transmitting side, and may include a function to request retransmission of lost PDCP PDUs.

[0218] The main functions of NR RLC (1035, 1060) may include some of the following functions:

[0219] - Data transfer function (Transfer of upper layer PDUs)

[0220] - In-sequence delivery of upper layer PDUs

[0221] - Out-of-sequence delivery of upper layer PDUs

[0222] - ARQ function (Error Correction through ARQ)

[0223] - Concatenation, segmentation and reassembly of RLC SDUs

[0224] - Re-segmentation of RLC data PDUs

[0225] - Reordering of RLC data PDUs

[0226] - Duplicate detection function

[0227] - Protocol error detection

[0228] - RLC SDU discard function

[0229] - RLC re-establishment function

[0230] In one example, the in-sequence delivery function of an NR RLC device refers to the function of sequentially delivering RLC SDUs received from a lower layer to an upper layer. The in-sequence delivery function of an NR RLC device may include a function of reassembling and delivering multiple RLC SDUs when an original RLC SDU is received divided into multiple RLC SDUs, a function of rearranging received RLC PDUs based on an RLC SN (sequence number) or a PDCP SN (sequence number), a function of recording lost RLC PDUs by rearranging the order, a function of reporting a status of lost RLC PDUs to the transmitting side, and a function of requesting retransmission of lost RLC PDUs. The in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer only the RLC SDUs up to the lost RLC SDU when there is a lost RLC SDU, or may include a function to sequentially deliver to the upper layer all RLC SDUs received before the timer starts if a predetermined timer has expired even if there is a lost RLC SDU. Alternatively, the in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer all RLC SDUs received up to the present if a predetermined timer has expired even if there is a lost RLC SDU.In addition, RLC PDUs can be processed in the order in which they are received (in the order of arrival, regardless of the order of sequence number) and delivered to the PDCP device out of order (out-of-sequence delivery). In the case of segments, segments stored in a buffer or to be received later can be received, reconstructed into a complete RLC PDU, processed, and delivered to the PDCP device. In one example, the NR RLC layer may not include a concatenation function, and the function can be performed in the NR MAC layer or replaced with a multiplexing function of the NR MAC layer.

[0231] The out-of-sequence delivery function of an NR RLC device refers to the function of directly delivering RLC SDUs received from a lower layer to an upper layer regardless of the order. It 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 any lost RLC PDUs.

[0232] NR MAC (1040, 1055) can be connected to multiple NR RLC layer devices configured in one terminal, and the main functions of NR MAC can include some of the following functions.

[0233] - Mapping function (Mapping between logical channels and transport channels)

[0234] - Multiplexing / demultiplexing of MAC SDUs

[0235] - Scheduling information reporting function

[0236] - HARQ function (Error correction through HARQ)

[0237] - Priority handling between logical channels of one UE

[0238] - Priority handling between UEs by means of dynamic scheduling

[0239] - MBMS service identification function

[0240] - Transport format selection function

[0241] - Padding function

[0242] The NR PHY layer (1045, 1050) can perform operations of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it through a wireless channel, or demodulating and channel decoding OFDM symbols received through a wireless channel and transmitting them to a higher layer.

[0243] The detailed structure of the wireless protocol structure can change 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 that has a single structure for each layer, such as in the single cell situation (1000). On the other hand, when the base station transmits data to a terminal based on CA (carrier aggregation) using multiple carriers in a single TRP, the base station and the terminal use a protocol structure that has a single structure up to the RLC but multiplexes the PHY layer through the MAC layer, such as in the carrier aggregation situation (1010). As another example, when a base station transmits data to a terminal based on DC (dual connectivity) using multiple carriers in multiple TRPs, the base station and the terminal use a protocol structure that has a single structure up to the RLC but multiplexes the PHY layer through the MAC layer, such as in the dual connectivity situation (1020).

[0244] Referring to the above-described PDCCH and beam configuration-related descriptions, the current Rel-15 and Rel-16 NR do not support repeated PDCCH transmission, making it difficult to achieve the required reliability in scenarios requiring high reliability, such as URLLC. The present invention provides a method for repeated PDCCH transmission through multiple transmission-reception points (TRPs) to improve the reliability of PDCCH reception by a terminal. The specific method is described in detail in the following examples.

[0245] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. The contents of the present disclosure can be applied to FDD and TDD systems. In the present disclosure below, upper signaling (or upper layer signaling) refers to a signal transmission method in which a base station transmits a signal to a terminal using a downlink data channel of a physical layer, or a terminal transmits a signal to a base station using an uplink data channel of a physical layer, and may also be referred to as RRC signaling, PDCP signaling, or MAC (medium access control) control element (MAC control element; MAC CE).

[0246] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as having the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied have a specific format, including a specific indicator that indicates whether cooperative communication is applied, scrambled with a specific RNTI by the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied, or assuming cooperative communication is applied in a specific section indicated by a higher layer. For the convenience of the following description, the case where the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as the NC-JT case.

[0247] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. Hereinafter, a base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, a gNB, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. Although embodiments of the present disclosure are described below using a 5G system as an example, embodiments of the present disclosure may be applied to other communication systems having similar technical backgrounds or channel types. For example, this may include LTE or LTE-A mobile communication and mobile communication technologies developed after 5G. Therefore, embodiments of the present disclosure may be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure as determined by a person skilled in the art. The contents of the present disclosure are applicable to FDD and TDD systems.

[0248] Additionally, when describing the present disclosure, detailed descriptions of related functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present disclosure. Furthermore, the terms described below are defined based on the functions of the present disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the contents of this specification.

[0249] In the following description of the present disclosure, upper layer signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

[0250] - MIB (Master Information Block)

[0251] - SIB (System Information Block) or SIB

[0252] - RRC (Radio Resource Control)

[0253] - MAC (Medium Access Control) CE (Control Element)

[0254] In addition, L1 signaling may be signaling corresponding to at least one or a combination of one or more signaling methods using the physical layer channel or signaling below.

[0255] - PDCCH (Physical Downlink Control Channel)

[0256] - DCI (Downlink Control Information)

[0257] - UE-specific DCI

[0258] - Group common DCI

[0259] - Common DCI

[0260] - Scheduling DCI (e.g. DCI used for scheduling downlink or uplink data)

[0261] - Non-scheduled DCI (e.g. DCI not intended for scheduling downlink or uplink data)

[0262] - PUCCH (Physical Uplink Control Channel)

[0263] - UCI (Uplink Control Information)

[0264] 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.

[0265] In the following disclosure, the above examples are described through various embodiments, but they are not independent and one or more embodiments may be applied simultaneously or in combination.

[0266] [Random Access procedure in SBFD]

[0267] Meanwhile, 3GPP introduced SBFD (Subband Non-Overlapping Full Duplex) as a new duplex method based on NR. SBFD is a technology that expands the uplink coverage of a terminal by utilizing a portion of downlink resources as uplink resources in a TDD band (spectrum) of 6 GHz or lower or 6 GHz or higher, thereby receiving uplink transmissions from terminals equivalent to the increased uplink resources, and reduces feedback delay by receiving feedback from the terminals regarding downlink transmissions in the expanded uplink resources. In the present disclosure, a terminal that receives information on whether SBFD is supported from a base station and can perform uplink transmissions in a portion of downlink resources may be conveniently referred to as an SBFD terminal (SBFD-capable UE). The following methods may be considered for defining the SBFD method in the standard and for an SBFD terminal to determine whether SBFD is supported in a specific cell (or frequency, frequency band).

[0268] In a first method, in addition to the frame structure type of the existing unpaired spectrum (or time division duplex, TDD) or paired spectrum (or frequency division duplex, FDD), another frame structure type (e.g., frame structure type 2) may be introduced to define the SBFD described above. Frame structure type 2 may be defined to be supported in the specific frequency or frequency band, or the base station may indicate to the terminal whether SBFD is supported as system information. The SBFD terminal may receive the system information including whether SBFD is supported and determine whether SBFD is supported in the specific cell (or frequency, frequency band).

[0269] In a second way, whether SBFD is additionally supported in a specific frequency or frequency band of an existing unpaired spectrum (or TDD) can be indicated without defining a new frame structure type. In the second way, whether SBFD is additionally supported in a specific frequency or frequency band of an existing unpaired spectrum can be defined, or the base station can indicate to the terminal whether SBFD is supported or not as system information. The SBFD terminal can receive the system information including whether SBFD is supported and determine whether SBFD is supported in a specific cell (or frequency, frequency band).

[0270] In the first and second methods described above, information on whether SBFD is supported may be information that indirectly indicates whether SBFD is supported by additionally setting a portion of downlink resources as uplink resources in addition to the settings for TDD UL (uplink)-DL (downlink) resource configuration information indicating TDD downlink slot (or symbol) resources and uplink slot (or symbol) resources (for example, SBFD resource configuration information in FIG. 12 described below), or may be information that directly indicates whether SBFD is supported.

[0271] In the present disclosure, an SBFD terminal can acquire cell synchronization by receiving a synchronization signal block during the initial cell access for connecting to a cell (or base station). The process for acquiring cell synchronization may be the same for both the SBFD terminal and the existing TDD terminal. Thereafter, the SBFD terminal can determine whether the cell supports SBFD through MIB acquisition, SIB acquisition, or a random access process.

[0272] System information for transmitting information on whether SBFD is supported may be system information transmitted separately from system information for terminals supporting other versions of the standard within the cell (e.g., existing TDD terminals), and the SBFD terminal may determine whether SBFD is supported by obtaining all or part of the system information for the existing TDD terminal and the separately transmitted system information. If the SBFD terminal obtains only the system information for the existing TDD terminal or obtains system information on non-support of SBFD, the cell (or base station) may determine that it supports only TDD.

[0273] If information about SBFD support is included in the system information for a terminal that supports a different version of the standard (e.g., a legacy TDD terminal), the information about SBFD support can be inserted at the very end so as not to affect the acquisition of system information by the legacy TDD terminal. If the SBFD terminal does not obtain the information about SBFD support inserted at the very end, or obtains information indicating that SBFD is not supported, the SBFD terminal can determine that the cell (or base station) only supports TDD.

[0274] If information on whether SBFD is supported is included in system information for a terminal supporting a different version of the standard (e.g., a legacy TDD terminal), the information on whether SBFD is supported may be transmitted through a separate PDSCH so as not to affect acquisition of system information by the legacy TDD terminal. That is, a terminal that does not support SBFD can receive a first SIB (or SIB1) including legacy TDD-related system information on a first PDSCH. An SBFD-supporting terminal can receive a first SIB (or SIB) including legacy TDD-related system information on a first PDSCH, and a second SIB including SBFD-related system information on a second PDSCH. Here, the first PDSCH and the second PDSCH can be scheduled as the first PDCCH and the second PDCCH, and the CRC (cyclic redundancy code) of the first PDCCH and the second PDCCH can be scrambled with the same RNTI (e.g., SI-RNTI). The search space for monitoring the second PDCCH can be obtained from the system information of the first PDSCH, and if not obtained (i.e., if the system information of the first PDSCH does not include information about the search space), the second PDCCH can be received in the same search space as the search space of the first PDCCH.

[0275] As above, when the SBFD terminal determines that the cell (or base station) supports only TDD, the SBFD terminal can perform random access procedures and transmit and receive data / control signals in the same manner as a conventional TDD terminal.

[0276] The base station may configure separate random access resources for each of an existing TDD terminal or an SBFD terminal (e.g., an SBFD terminal supporting duplex communication and an SBFD terminal supporting half-duplex communication), and transmit configuration information (control information or configuration information indicating time-frequency resources that can be used for PRACH) for the random access resources to the SBFD terminal through system information. The system information for transmitting information for the random access resources may be separately transmitted system information that is distinct from system information for terminals supporting different versions of standards within a cell (e.g., an existing TDD terminal).

[0277] The base station configures random access resources for TDD terminals and can additionally configure separate random access resources for SBFD terminals. Here, SBFD terminals may use the random access resources for TDD terminals, or they may not be able to use the random access resources for TDD terminals. In the latter case, SBFD terminals can only use the separate random access resources for SBFD terminals.

[0278] An SBFD terminal can be instructed by the base station whether or not it can use random access resources for TDD terminals. This can be indicated by being included in the SIB. That is, separate random access resources for SBFD terminals can be configured in the SIB, and along with the configuration of separate random access resources for SBFD terminals, the availability of random access resources for TDD terminals can be indicated. This can be indicated by 1 bit. If 1 bit is '0' (or FALSE), the SBFD terminal cannot use random access resources for TDD terminals. If 1 bit is '1' (or TRUE), the SBFD terminal can use random access resources for TDD terminals.

[0279] The base station can determine the type of terminal attempting to access the cell based on the random access resources used by the terminal. For example, an SBFD terminal can transmit a PRACH through a separate random access resource for SBFD terminals, and the base station can determine that the SBFD terminal is attempting to access the cell when receiving the PRACH. For example, a TDD terminal can transmit a PRACH through a random access resource for TDD terminals, and the base station can determine that the TDD terminal is attempting to access the cell when receiving the RPACH. For reference, if an SBFD terminal is allowed to transmit a PRACH through the random access resource of a TDD terminal, the base station may be ambiguous as to whether the type of the terminal that transmitted the PRACH is a TDD terminal or an SBFD terminal. In this case, the base station can always assume that the type of the terminal is a TDD terminal.

[0280] When the base station determines that the terminal is an SBFD terminal, the base station may schedule msg2, msg3, msg4, etc. to the terminal based on the uplink subband configuration. That is, when the base station schedules reception of msg2 and msg4 to the terminal, msg2 and msg4 may be scheduled not to be received in the uplink subband (when the terminal receives a PDSCH including msg2 and msg4, the PDSCH is received in a frequency resource excluding the uplink subband). When the base station schedules msg3 PUSCH to the terminal, msg3 PUSCH may be scheduled to be transmitted within the uplink subband.

[0281] If the base station determines that the terminal is a TDD terminal, the base station cannot use the uplink subband configuration when scheduling msg2, msg3, and msg4 to the terminal. That is, even if the uplink subband is configured in the downlink symbol or flexible symbol, the base station can assume that the terminal cannot obtain the uplink subband configuration information. When the base station schedules msg3 PUSCH to the terminal, the msg3 PUSCH can be scheduled in the flexible symbol or the uplink symbol. In other words, the msg3 PUSCH cannot be scheduled in the uplink subband.

[0282] In one example, a base station may set a common random access resource for all terminals within a cell, without setting a separate random access resource for an SBFD terminal. In this case, configuration information for the random access resource may be transmitted to all terminals within the cell through system information, and an SBFD terminal that has received the system information may perform random access to the random access resource. Thereafter, the SBFD terminal may complete the random access process and proceed to an RRC connection mode for transmitting and receiving data with the cell. After the RRC connection mode, the SBFD terminal may receive an upper layer or physical signal from the base station that can determine that a part of the frequency resource of the downlink time resource is set as an uplink resource, and may perform an SBFD operation, for example, transmit an uplink signal on the uplink resource.

[0283] When the SBFD terminal determines that the cell supports SBFD, the terminal may notify the base station that the terminal attempting to connect is an SBFD terminal by transmitting capability information including at least one or more of whether the terminal supports SBFD, whether full-duplex communication or half-duplex communication is supported, and the number of transmit or receive antennas that the terminal has (or supports). Alternatively, when half-duplex communication support is a mandatory implementation for the SBFD terminal, whether half-duplex communication is supported may be omitted from the capability information. The SBFD terminal may report capability information to the base station through a random access procedure, may report to the base station after completing the random access procedure, or may report to the base station after proceeding to an RRC connection mode for transmitting and receiving data with the cell.

[0284] SBFD terminals can support half-duplex communication, which performs only uplink transmission or downlink reception at a time like existing TDD terminals, or can support full-duplex communication, which performs both uplink transmission and downlink reception at a time. Therefore, whether the SBFD terminal supports half-duplex or full-duplex communication can be reported to the base station through a capability report, and after the capability report, the base station can configure the SBFD terminal to transmit and receive using half-duplex communication or full-duplex communication. When the SBFD terminal reports the capability for half-duplex communication to the base station, since a duplexer generally does not exist, a switching gap may be required to change the RF between transmission and reception when operating in FDD or TDD.

[0285] Typically, a terminal can establish a wireless link with a network through a random access procedure based on synchronization with the network and system information acquired during the cell search process. Random access can be either contention-based or contention-free. Contention-based random access can be used when a terminal performs cell selection and reselection during the initial cell access phase, for example, when moving from the RRC_IDLE state to the RRC_CONNECTED state. Contention-free random access can be used to reestablish uplink synchronization when downlink data arrives, in the case of a handover, or in the case of position measurement.

[0286] FIG. 11 is a diagram illustrating a random access procedure in a wireless communication system to which the present disclosure applies.

[0287] Referring to FIG. 11, a contention-based random access procedure is illustrated as an example. In addition, although not illustrated, the base station may transmit a synchronization signal block as described in the above-described embodiments. At this time, the base station may periodically transmit the synchronization signal block using beam sweeping. For example, the base station may transmit a synchronization signal block including a PSS / SSS (synchronization signal) and a PBCH (broadcast channel) signal using up to 64 different beams for 5 ms, and multiple synchronization signal blocks may be transmitted using different beams. The terminal may detect (select) a synchronization signal block having an optimal beam direction (e.g., a beam direction with the strongest received signal strength or greater than a predetermined threshold) and transmit a preamble using a PRACH (physical random access channel) resource associated with the detected synchronization signal block. For example, as a first step (1101) of the random access procedure, the terminal may transmit a random access preamble (or message 1) to the base station. A base station that receives a random access preamble can measure a transmission delay value between a terminal and the base station and synchronize uplink. Specifically, the terminal can transmit a random access preamble randomly selected from a random access preamble set given in advance by system information. In addition, the initial transmission power of the random access preamble can be determined according to the path loss between the terminal and the base station measured by the terminal. In addition, the terminal can determine the transmission beam direction (or transmission beam or beam) of the random access preamble based on the synchronization signal block received from the base station and transmit the random access preamble by applying the determined transmission beam direction.

[0288] In the second step (1102), the base station can transmit a response (random access response, RAR, or message 2 (msg2)) to the terminal for the detected random access attempt. The base station can transmit an uplink transmission timing control command to the terminal based on a transmission delay value measured from the random access preamble received in the first step. In addition, the base station can transmit an uplink resource and power control command to be used by the terminal as scheduling information. The scheduling information can include control information for the uplink transmission beam of the terminal. The RAR is transmitted through the PDSCH and can include at least one of the following information.

[0289] - Random access preamble sequence index detected by the network (or base station)

[0290] - TC-RNTI (temporary cell radio network temporary identifier)

[0291] - Uplink scheduling grant

[0292] - Timing advance value

[0293] If the terminal does not receive RAR, which is scheduling information for message 3, from the base station for a predetermined period of time in the second step (1102), the first step (1101) may be performed again. If the first step is performed again, the terminal transmits the random access preamble by increasing the transmission power by a predetermined step (this is called power ramping), thereby increasing the probability of the base station receiving the random access preamble.

[0294] In the third step (1103), the terminal may transmit uplink information (scheduled transmission, or message 3) including its terminal identifier (which may be referred to as UE contention resolution identity) (or a valid terminal identifier (C-RNTI) if the terminal already has a valid terminal identifier within the cell before initiating the random access procedure) to the base station through an uplink data channel (physical uplink shared channel, PUSCH) using the uplink resources allocated in the second step (1102). The PUSCH may be referred to as message 3 PUSCH (msg3 PUSCH). The transmission timing of the uplink data channel for transmitting message 3 may follow the uplink transmission timing control command received from the base station in the second step (1102). In addition, the transmission power of the uplink data channel for transmitting message 3 may be determined in consideration of the power control command received from the base station in the second step (1102) and the power ramping value of the random access preamble. There is. The uplink data channel for transmitting the above message 3 may be the first uplink data signal transmitted by the terminal to the base station after the terminal transmits the random access preamble.

[0295] Finally, in the fourth step (1104), if the base station determines that the terminal has performed random access without collision with other terminals, the base station may transmit to the terminal a message (contention resolution message (CR message), or message 4)) including the identifier of the terminal that transmitted the uplink data in the third step (1103). In this regard, if multiple terminals receive the same TC-RNTI in the second step (1102), each of the multiple terminals that received the same TC-RNTI may include its own terminal identifier (UE contention resolution identity) in message 3 in the third step (1103) and transmit the message 3 to the base station, and the base station may transmit message 4 (CR message) including the terminal identifier of one of the identifiers of the multiple terminals to resolve the contention. When the terminal receives message 4 (CR message) including its terminal identifier from the base station in the fourth step (1104) (or transmits message 3 including terminal identifier (C-RNTI) in the third step (1103) and receives terminal-specific control information including CRC based on the terminal identifier (C-RNTI) through PDCCH in the fourth step (1104), it can determine that random access is successful. Accordingly, among multiple terminals that have received the same TC-RNTI from the base station, a terminal that confirms that its terminal identifier is included in message 4 (CR message) can confirm that the contention is successful. In addition, the terminal can transmit HARQ-ACK / NACK indicating whether message 4 was successfully received to the base station through an uplink control channel (physical uplink control channel, PUCCH).

[0296] If the data transmitted by the terminal in step 3 (1103) collides with data from another terminal, causing the base station to fail to receive a data signal from the terminal, the base station may not perform any further data transmission to the terminal. Accordingly, if the terminal fails to receive data transmitted from the base station in step 4 (1104) for a certain period of time, the random access procedure may be determined to have failed, and the procedure may be restarted from step 1 (1101).

[0297] As described above, in the first step (1101) of the random access process, the terminal can transmit a random access preamble on the PRACH. Each cell has 64 available preamble sequences, and four long preamble formats and nine short preamble formats can be used depending on the transmission type. The terminal generates 64 preamble sequences using the root sequence index and cyclic shift value signaled as system information, and can randomly select one sequence to use as a preamble.

[0298] The base station can inform the terminal of the configuration information for random access resources, for example, control information (or configuration information) indicating time-frequency resources that can be used for PRACH, using at least one of SIB, higher layer signaling (RRC (Radio Resource Control) information), or DCI (Downlink Control Information). The frequency resource for PRACH transmission can indicate the start RB point of transmission to the terminal, and the number of RBs used can be determined according to the preamble format transmitted through PRACH and the applied subcarrier spacing. The time resource for PRACH transmission can inform the preset PRACH configuration period, the subframe index and start symbol including the PRACH transmission time (PRACH occasion, which can be used interchangeably with transmission time), and the number of PRACH transmission time points in a slot, etc., through the PRACH configuration index (0 to 255), as shown in Table 16 below. The terminal can determine the validity of the PRACH transmission times indicated by the PRACH configuration index, and determine only the valid PRACH transmission times as PRACH transmission times at which the random access preamble can be transmitted. Through the PRACH configuration index, the random access configuration information included in the SIB, and the index of the SSB selected by the terminal, the terminal can check the time and frequency resources for transmitting the random access preamble, and transmit the selected sequence as a preamble to the base station.

[0299] [Table 16]

[0300]

[0301] Meanwhile, according to an embodiment of the present disclosure, a method of determining the validity of a PRACH transmission time point through a PRACH configuration index and SBFD settings for an SBFD terminal to perform PRACH transmission, and performing PRACH transmission through the PRACH transmission time point determined to be valid, and a procedure of the SBFD terminal is required when the valid PRACH transmission time point and downlink reception overlap.

[0302] Accordingly, the method by which the SBFD terminal determines the validity of the PRACH transmission time and the operation of the SBFD terminal when the valid PRACH transmission time and downlink reception are set or scheduled to occur simultaneously will be described using FIGS. 12, 13, and 14.

[0303] FIG. 12 is a diagram illustrating an example of SBFD operation in a TDD band of a wireless communication system according to one embodiment of the present disclosure.

[0304] Fig. 12(a) illustrates a case where TDD is operated in a specific frequency band. In a cell operating TDD, a base station can transmit and receive signals including data / control information in a downlink slot (or symbol), an uplink slot (or symbol) (1201, or 1211 in Fig. 12(b), 1221 in Fig. 12(c), 1231 in Fig. 12(d)), and a flexible slot (or symbol) based on the settings for TDD UL-DL resource configuration information indicating downlink slot (or symbol) resources and uplink slot (or symbol) resources with an existing TDD terminal or an SBFD terminal.

[0305] In Fig. 12, it can be assumed that the DDDSU slot format is set according to the TDD UL-DL resource configuration information. Here, 'D' is a slot composed entirely of downlink symbols, 'U' is a slot composed entirely of uplink symbols, and 'S' is a slot that is not 'D' or 'U', that is, a slot that includes a downlink symbol or an uplink symbol or a flexible symbol. Here, for convenience, it can be assumed that S is composed of 12 downlink symbols and 2 flexible symbols. In addition, the DDDSU slot format can be repeated according to the TDD UL-DL resource configuration information. That is, the repetition period of the TDD configuration is 5 slots (5 ms for 15 kHz SCS, 2.5 ms for 30 kHz SCS, etc.).

[0306] Next, Figures 12(b), 12(c), and 12(d) illustrate cases where SBFD is operated together with TDD in a specific frequency band.

[0307] Referring to Fig. 12(b), the terminal can set a portion of the frequency band of the cell as a frequency band (1210) capable of uplink transmission. This band can be called an uplink subband (UL subband). And the uplink subband (UL subband) can be applied to all symbols of all slots. The terminal can transmit an uplink channel or signal scheduled for all symbols (1212) within the subband (UL subband). However, the terminal cannot transmit an uplink channel or signal in a band other than the subband (UL subband).

[0308] Referring to Fig. 12(c), the terminal may set a portion of the frequency band of the cell as a frequency band (1220) capable of uplink transmission, and may set a time region in which the frequency band is activated. Here, this frequency band may be called an uplink subband (UL subband). In Fig. 12(c), the uplink subband (UL subband) is deactivated in the first slot, and the uplink subband (UL subband) may be activated in the remaining slots. Accordingly, the terminal may transmit an uplink channel or signal in the uplink subband (UL subband) (1222) of the remaining slots. Therefore, although the uplink subband (UL subband) is activated in units of slots here, whether it is activated or not may be set in units of symbols.

[0309] Referring to FIG. 12(d), a terminal may be configured with time-frequency resources capable of uplink transmission. The terminal may configure one or more time-frequency resources as time-frequency resources capable of uplink transmission. For example, some frequency bands (1232) of the first and second slots may be configured as time-frequency resources capable of uplink transmission. Additionally, some frequency bands (1233) of the third slot and some frequency bands (1234) of the fourth slot may be configured as time-frequency resources capable of uplink transmission.

[0310] In the following description, the time-frequency resources that enable uplink transmission in downlink symbols or flexible symbols may be referred to as SBFD resources / UL subbands.

[0311] Meanwhile, the base station can transmit PRACH settings to the terminal as system information, and RACH opportunities (Occasions) can be set according to the PRACH settings. The terminal can determine that all or some of the RACH opportunities are valid.

[0312] The first valid RACH opportunities can be determined based on the first PRACH configuration (PRACH configuration for TDD terminal).

[0313] In an FDD cell, all first RACH opportunities according to the established first PRACH configuration can be defined as valid.

[0314] In a TDD cell, only the second RACH opportunity that satisfies the following conditions among the configured second PRACH settings can be considered valid.

[0315] - If TDD DL / UL configuration information is not received from the system information, the RACH opportunity in the PRACH slot does not precede SS / PBCH, and N from the last received symbol of SS / PBCH gap If it starts after the symbol, the above RACH opportunity can be judged to be valid.

[0316] - When TDD DL / UL configuration information is received from the system information, the RACH opportunity in the UL symbol or the RACH opportunity in the PRACH slot does not precede the SS / PBCH, and N from the last received symbol of the SS / PBCH. gap A RACH opportunity can be considered valid if it starts after the symbol and after the last DL symbol.

[0317] The above method is an example of this, and first valid RACH opportunities can be determined by other methods.

[0318] FIG. 13 is a diagram illustrating valid RACH opportunities in a TDD configuration and an SBFD configuration according to an embodiment of the present disclosure.

[0319] Referring to Fig. 13(a), it is assumed that the terminal has received DDDSU with TDD DL / UL configuration information, and the first RACH opportunity is configured for each slot according to the first PRACH configuration. The terminal can determine that the first PRACH configuration overlapping with the UL symbol is the first valid RACH opportunity. At this time, the 5th slot (the last slot of the TDD period configured with DDDSU) is an uplink slot, and the first RACH opportunity (1301) may be valid. However, the first RACH opportunities of the 1st, 2nd, 3rd, and 4th slots (the first four slots of the TDD period configured with DDDSU) (1302) may not be valid because they do not start after the last downlink symbol. Accordingly, the terminal can determine that the first RACH opportunities of four uplink slots (the 5th, 10th, 15th, and 20th) within 20 slots are valid, and determine that the first RACH opportunities of the remaining 16 slots are invalid.

[0320] When an SBFD terminal is configured with time-frequency resources for uplink transmission and SBFD uplink resources, second valid RACH opportunities can be determined based on the second PRACH configuration (PRACH configuration for an SBFD terminal). The terminal can determine the validity of the second RACH opportunity as follows.

[0321] - If TDD DL / UL configuration information is not received from the system information, the second RACH opportunity in the PRACH slot does not precede SS / PBCH, and N from the last received symbol of SS / PBCH. gap If it starts after the symbol, the second RACH opportunity can be considered valid.

[0322] - When TDD DL / UL configuration information is received from the system information, the 2nd RACH opportunity in the UL symbol or the RACH opportunity in the PRACH slot does not precede the SS / PBCH, and N from the last received symbol of the SS / PBCH.gap It can be determined to be valid if it starts after the symbol and the second RACH opportunity is located within the SBFD uplink resource.

[0323] That is, compared to the first valid RACH opportunities, when TDD DL / UL configuration information is received from the system information, the RACH opportunities included in the SBFD uplink resource region within the DL symbol can become the second valid RACH opportunities. Therefore, the terminal can obtain more RACH opportunities through the above method.

[0324] However, in the first method, the second RACH opportunity may not be valid depending on the location of the SS / PBCH. Furthermore, if the second RACH opportunity is set on a SBFD uplink resource (a resource capable of uplink transmission), the second RACH opportunity may be limited in the resource. This issue can be resolved in the second method.

[0325] In the second method of the present disclosure, when the SBFD terminal is configured with time-frequency resources for uplink transmission, SBFD uplink resources, the terminal can determine the validity of the second RACH opportunity as follows.

[0326] - If TDD DL / UL configuration information is not received from the system information, the second RACH opportunity in the PRACH slot does not precede SS / PBCH, and N from the last received symbol of SS / PBCH. gap If it starts after the symbol, the second RACH opportunity can be judged to be valid.

[0327] - When TDD DL / UL configuration information is received from system information, it can be determined to be valid if the second RACH opportunity within the UL symbol or the above RACH opportunity is located within the SBFD resource.

[0328] The above first and second methods are examples of this, and second valid RACH opportunities may be determined by other methods.

[0329] Referring to FIGS. 13(b), 13(c), and 13(d), the terminal can determine whether the second RACH opportunity is valid based on TDD UL-DL resource configuration information and SBFD uplink resource information.

[0330] Referring to Fig. 13(b), the terminal can be configured with an uplink subband (UL subband) (1310), and the resource of the uplink subband of the downlink symbol can be determined as an SBFD uplink resource. According to methods 1 and 2 (there is no difference between methods 1 and 2 since SS / PBCH is not illustrated in Fig. 13), the terminal can determine that the second RACH opportunity (1311) is valid because the SBFD uplink resource of the preceding 4 slots of the TDD cycle includes the second RACH opportunity.

[0331] For reference, in Fig. 13(b), when an uplink subband (UL subband) (1310) is set, uplink transmission is possible in all symbols using the resources of the uplink subband (UL subband). Therefore, the first and second methods described above can be briefly described as follows.

[0332] In the method 1-1 of the present disclosure, when the SBFD terminal is configured with time-frequency resources for uplink transmission, SBFD resources, the terminal can determine the validity of the second RACH opportunity as follows.

[0333] - If the frequency band of the RACH opportunity set according to the PRACH configuration is included in the uplink subband (UL subband), the second RACH opportunity in the PRACH slot does not precede the SS / PBCH, but is N from the last received symbol of the SS / PBCH. gapIf it starts after the symbol, the second RACH opportunity can be judged to be valid.

[0334] In the method 2-1 of the present disclosure, when a SBFD terminal is set with time-frequency resources for uplink transmission, SBFD resources, the terminal can determine the validity of a RACH opportunity as follows.

[0335] - If the frequency band of the second RACH opportunity set according to the PRACH setting is included in the uplink subband (UL subband), all RACH opportunities may be valid.

[0336] The above methods 1-1 and 2-1 are examples, and second valid RACH opportunities may be determined by other methods.

[0337] Referring to FIG. 13(c), the terminal can be configured with an uplink subband (UL subband) (1320) and a time domain in which the uplink subband is activated, and the resource of the uplink subband of the downlink symbol of the activated time domain can be determined as an SBFD uplink resource. According to methods 1 and 2 (there is no difference between methods 1 and 2 since SS / PBCH is not illustrated in FIG. 13), the terminal can determine that the second RACH opportunity (1321) is valid because the SBFD uplink resource of the second, third, and fourth slots of the TDD period includes the second RACH opportunity (1321). For reference, the second RACH opportunity (1322) of the first slot of the TDD period is not included in the SBFD uplink resource, and therefore can be determined to be invalid.

[0338] Referring to FIG. 13(d), the terminal can be configured with the time-frequency domain of the SBFD uplink resource, and according to methods 1 and 2 (since SS / PBCH is not illustrated in FIG. 13, there is no difference between methods 1 and 2), the second RACH opportunity overlapping with the SBFD uplink resource can be determined to be valid. That is, the second RACH opportunity (1331) of the first and second slots of the TDD cycle can be considered valid because it is included in the SBFD uplink resource. However, the second RACH opportunity (1332) of the third and fourth slots may not be valid because it is not included in the SBFD uplink resource.

[0339] Although not specifically mentioned in FIGS. 13(b), 13(c), and 13(d), the second RACH opportunity overlapping with the UL symbol may always be valid. However, the UE may be configured with SBFD downlink resources capable of DL transmission within the UL symbol. In this case, if the SBFD downlink resources overlap with the second RACH opportunity, the RACH opportunity may be invalid. Alternatively, even if the SBFD downlink resources overlap with the RACH opportunity, the second RACH opportunity may be valid. That is, the SBFD downlink resources configured in the UL symbol may be ignored when determining a valid second RACH opportunity.

[0340] The above-described first and second methods can be used when a single PRACH configuration is configured for a TDD terminal (a terminal other than an SFBD terminal) and an SFBD terminal. That is, based on a single PRACH resource configuration, a TDD terminal can determine a first valid RACH opportunity according to a method of a TDD cell (Fig. 13(a)), and an SFBD terminal can determine a second valid RACH opportunity according to the above-described first and second methods (Figs. 13(b), 13(c), 13(d)).

[0341] In a 5G system, a terminal can receive a synchronization signal block and configure a Control Resource Set (CORESET)#0 (which may correspond to a control resource set with a control resource set index or ID (Identity) of 0) and a Search Space#0 (which may correspond to a search space with a search space index or ID of 0) from the synchronization signal block. The terminal can monitor CORESET#0 assuming that the selected synchronization signal block and the DMRS (Demodulation Reference signal) transmitted in CORESET#0 are QCLed (Quasi Co Located). In addition, the terminal can receive system information based on the downlink control information transmitted in CORESET#0. The terminal can obtain PRACH-related configuration information for random access from the received system information. A terminal that has acquired PRACH-related configuration information can transmit a preamble to a base station on the PRACH based on the index of the received synchronization signal block when performing random access (for example, when the terminal receives a synchronization signal block with the corresponding index, the terminal transmits a preamble on the PRACH using a transmission beam that has a QCL relationship with a reception beam), and the base station that has received a preamble from the terminal through the PRACH can obtain information about the index of the synchronization signal block selected (received) by the terminal. When transmitting Msg2 (for example, 1102 of FIG. 11), the base station can transmit a PDCCH or Msg2 PDSCH that schedules the Msg2 PDSCH using a transmission beam that has the same QCL relationship as the synchronization signal block corresponding to the received PRACH. Accordingly, the terminal can receive the PDCCH or Msg2 PDSCH that schedules the Msg2 PDSCH using the reception beam used when receiving the synchronization signal block corresponding to the selected (transmitted) PRACH.

[0342] The terminal can receive information from the base station regarding the mapping between a valid RACH opportunity and a synchronization signal block (SSB or SS / PBCH block). This configuration information can be included in SIB1 or a dedicated RRC signal, and the same value can be set for all terminals within the cell based on the configuration information. Based on this configuration information, the terminal can determine the mapping between a valid RACH opportunity and a synchronization signal block.

[0343] A terminal may receive first information regarding a mapping between first valid RACH opportunities and synchronization signal blocks from a base station, and may receive second information regarding a mapping between second valid RACH opportunities and synchronization signal blocks. In this case, the terminal may map the first valid RACH opportunities and synchronization signal blocks using the first information, and may map the second valid RACH opportunities using the second information. Here, the first information regarding the mapping between the first valid RACH opportunities and synchronization signal blocks may be received by both a TDD terminal (a terminal that does not support SBFD operation) and an SBFD terminal, but the second information regarding the mapping between the second valid RACH opportunities and synchronization signal blocks may be received only by an SBFD terminal.

[0344] The mapping between valid RACH opportunities and synchronization signal blocks can be determined as follows. Note that the following process can be performed independently for the first valid RACH opportunities and the second valid RACH opportunities.

[0345] Valid RACH opportunities can be indexed sequentially, starting from 0. Each valid RACH opportunity is assigned a unique index, and the index can be mapped to an index between the synchronization signal block. For convenience, in this disclosure, it is assumed that valid RACH opportunities are indexed in chronological order. Note that if valid RACH opportunities are established in different frequency domains at the same time, the indexes can be assigned first according to frequency domain and then according to chronological order.

[0346] Based on the information about the mapping between valid RACH opportunities and synchronization signal blocks, N valid RACH opportunities can be mapped to one synchronization signal block, where N is 1 or greater. In this case, valid RACH opportunities with indices 0, 1, ..., N-1 can be mapped to the synchronization signal block with index 0. In general, valid RACH opportunities with indices i*N, i*N+1, ..., (i+1)*N-1 can be mapped to the synchronization signal block with index i, where i=0,1,2 ...

[0347] Based on the information about the mapping between a valid RACH opportunity and a synchronization signal block, one valid RACH opportunity can be mapped to M synchronization signal blocks, where M is 1 or greater. In this case, a RACH opportunity with index i can be mapped to synchronization signal blocks with indices i*M, i*M+1,...,(i+1)*M-1, where i=0,1,2... Note that in this case, the preambles of one RACH opportunity are divided into M sets, and each set can be mapped to one synchronization signal block.

[0348] According to one embodiment of the present disclosure, a first valid RACH opportunity and a second valid RACH opportunity may be mapped to one synchronization signal block.

[0349] A base station can instruct a terminal to transmit a PRACH preamble. The process by which a terminal transmits a PRACH preamble and establishes random access is called contention-free random access. Contention-free access is achieved because the base station explicitly indicates to the terminal which PRACH preamble to transmit.

[0350] More specifically, the instruction to transmit the PRACH preamble for CFRA can be indicated as follows.

[0351] The terminal can receive DCI format 1_0 with CRC scrambled with C-RNTI. If all frequency domain resource assignment fields of the DCI format 1_0 are '1', the terminal can determine that DCI format 1_0 is a DCI indicating PRACH preamble transmission for CFRA. This DCI can be called PDCCH order.

[0352] The DCI format may then include fields such as those in Table 17.

[0353] [Table 17]

[0354]

[0355] Referring to Table 17, the PDCCH order (requesting PRACH preamble transmission for CFRA) can be determined by the following process.

[0356] The SS / PBCH index field may indicate the index of the SS / PBCH. The SS / PBCH index field may indicate a value between 0 and 63, and the terminal may determine the SS / PBCH corresponding to the value. As described above, valid RACH opportunities mapped to the synchronization signal block (SS / PBCH) may be determined. Here, the valid RACH opportunities may be one or multiple. Therefore, it must be determined which of the valid RACH opportunities will transmit the PRACH preamble.

[0357] The PRACH Mask index field may indicate valid RACH opportunities among valid RACH opportunities that the UE will use for PRACH preamble transmission. More specifically, the PRACH Mask index may indicate a row of Table 18. For example, if 0 is indicated as the PRACH Mask index, PRACH preamble transmission may be allowed in all valid RACH opportunities mapped to the synchronization signal block (SS / PBCH). If 1 to 8 are indicated as the PRACH Mask index, PRACH preamble transmission may be allowed in each of indices 1 to 8 among valid RACH opportunities mapped to the synchronization signal block (SS / PBCH). If 9 is indicated as the PRACH Mask index, PRACH preamble transmission may be allowed in even indices among valid RACH opportunities mapped to the synchronization signal block (SS / PBCH). When 10 is indicated as the PRACH Mask index, PRACH preamble transmission may be allowed in odd indices among valid RACH opportunities mapped to the synchronization signal block (SS / PBCH).

[0358] [Table 18]

[0359]

[0360] Finally, one PRACH preamble index can be indicated in the valid RACH opportunity(s) allowed for transmission via the Random Access Preamble index field.

[0361] To summarize the series of processes, the terminal can determine the corresponding valid RACH opportunities by receiving the index of the SS / PBCH from the SS / PBCH index field of the PDCCH order, determine the valid RACH opportunities that are allowed for transmission among the valid RACH opportunities from the PRACH Mask Index field, and determine the index of the PRACH preamble to be transmitted in the valid RACH opportunities that are allowed for transmission through the Random Access Preamble index field. The terminal can transmit the PRACH preamble.

[0362] The problem addressed in this disclosure is that, since the first valid RACH opportunities and the second valid RACH opportunities are mapped to a single SS / PBCH index, the base station cannot indicate a single type of valid RACH opportunities to the UE through the above process. For reference, even if the PRACH Mask Index field indicates a row corresponding to PRACH Mask Index 1 to 8 of Table 18, the first valid RACH opportunities and the second valid RACH opportunities are separately indexed, so it is not possible to indicate a single type of RACH opportunities.

[0363] <Example 1: Instruction using DCI information>

[0364] In a first embodiment of the present disclosure, the terminal can determine which of the first valid RACH opportunities and the second valid RACH opportunities indicate transmission of the PRACH preamble by using some fields of the DCI format 1_0 indicating the PDCCH order.

[0365] More specifically, the terminal can determine one type of opportunity among the first valid RACH opportunities and the second valid RACH opportunities using 1 bit of DCI format 1_0. For example, if 1 bit is '0', it can be determined that PRACH preamble transmission is allowed / instructed in the first type RACH opportunities. And, it can be determined that PRACH preamble transmission is not allowed or instructed in the second type RACH opportunities. If 1 bit is '1', it can be determined that PRACH preamble transmission is allowed / instructed in the second type RACH opportunities. And, it can be determined that PRACH preamble transmission is not allowed or instructed in the first type RACH opportunities.

[0366] The terminal can determine one or more types of opportunities among the first valid RACH opportunities and the second valid RACH opportunities using bit 2 of DCI format 1_0. For example, if bit 2 is '00', it can be determined that PRACH preamble transmission is allowed / indicated in the first type RACH opportunities. In addition, it can be determined that PRACH preamble transmission is not allowed or not indicated in the second type RACH opportunities. If bit 2 is '01', it can be determined that PRACH preamble transmission is allowed / indicated in the second type RACH opportunities. In addition, it can be determined that PRACH preamble transmission is not allowed or not indicated in the first type RACH opportunities. If bit 2 is '10', it can be determined that PRACH preamble transmission is allowed / indicated in the first type RACH opportunities and the second type RACH opportunities. The case where bit 2 is '11' may not be defined.

[0367] The UE can use two bits in DCI format 1_0 to determine one or more types of opportunities among the first valid RACH opportunities and the second valid RACH opportunities. For example, one bit (e.g., MSB) of the two bits can indicate whether PRACH preamble transmission is allowed in the first type RACH opportunities, and the other bit (e.g., LSB) of the two bits can indicate whether PRACH preamble transmission is allowed in the second type RACH opportunities. If one bit is '0', it can be determined that PRACH preamble transmission is not allowed or not indicated in the corresponding type of RACH opportunities. If one bit is '1', it can be determined that PRACH preamble transmission is allowed / indicated in the corresponding type of RACH opportunities. The UE may not expect that both types of RACH opportunities are not allowed for transmission (two bits are '00').

[0368] The UE can obtain 1 or 2 bits from the Reserved bits in DCI format 1_0. Referring to Table 17, DCI format 1_0, which indicates the PDCCH order, may include Reserved bits. The UE can use 1 or 2 bits from the Reserved bits to be instructed on which types of RACH opportunities it can transmit the PRACH preamble.

[0369] The terminal may reuse at least 1 bit of the UL / SUL indicator field among 1 or 2 bits in DCI format 1_0. The UL / SUL indicator field may be used when it is reserved.

[0370] If the terminal determines that PRACH preamble transmission is allowed / instructed in Type 1 RACH opportunities, the indices of RACH opportunities for which transmission is allowed in the PRACH Mask index field may be considered as indices of Type 1 PRACH opportunities.

[0371] If the terminal determines that PRACH preamble transmission is allowed / instructed in the second type RACH opportunities, the indices of the RACH opportunities for which transmission is allowed in the PRACH Mask index field may be considered as the indices of the second type PRACH opportunities.

[0372] When the terminal determines that PRACH preamble transmission is permitted / instructed in the first type RACH opportunities and the second type RACH opportunities, the indices of the RACH opportunities for which transmission is permitted in the PRACH Mask index field may be regarded as the indices of the first type PRACH opportunities and the indices of the second type PRACH opportunities, respectively.

[0373] FIG. 15 is a flowchart illustrating the operation of a terminal according to an embodiment of the present disclosure. Specifically, FIG. 15 is a diagram illustrating the operation of a terminal according to the first embodiment.

[0374] Referring to FIG. 15, the terminal can perform the following steps.

[0375] The terminal can determine first valid RACH opportunities and second valid RACH opportunities in the first step (1500).

[0376] Here, the first valid RACH opportunities may be valid RACH opportunities that can be used by both TDD terminals (terminals that do not support SBFD operation) and SBFD terminals. The first valid RACH opportunities may be determined according to the first PRACH configuration. The first valid RACH opportunities may be RACH opportunities located in a Flexible symbol or an UL symbol. If the first valid RACH opportunities are located in a Flexible symbol, they may be RACH opportunities that start a certain number of symbols after the last symbol of the SS / PBCH. If they are located in a Flexible symbol, they may be RACH opportunities that start a certain number of symbols after the last symbol of the DL symbols.

[0377] Here, the second valid RACH opportunities can be determined according to the second PRACH configuration. The second PRACH configuration can set valid RACH opportunities in SBFD resources. That is, the second valid RACH opportunities can be located within SBFD resources. In addition, the second PRACH configuration can set valid RACH opportunities in SBFD resources, flexible symbols, and UL symbols. That is, depending on the second PRACH configuration, the second valid RACH opportunities can be located within SBFD resources, flexible symbols, and UL symbols.

[0378] The terminal can map each of the first valid RACH opportunities and the second valid RACH opportunities to the SS / PBCH. The first valid RACH opportunities are indexed, and the mapping can be determined based on the index and the SS / PBCH index. Information for the mapping can be instructed from the base station. The second valid RACH opportunities are indexed, and the mapping can be determined based on the index and the SS / PBCH index. Information for the mapping can be instructed from the base station. Here, the mapping of the first valid RACH opportunities and the SS / PBCH and the mapping of the second valid RACH opportunities and the SS / PBCH can be performed independently. Two types (the first valid RACH opportunities and the second valid RACH opportunities) can be mapped to one SS / PBCH simultaneously.

[0379] In the second step (1510), the terminal can receive DCI format 1_0 with CRC scrambled with C-RNTI. The terminal can set a search space for receiving DCI format 1_0 from the base station. The terminal can set a C-RNTI value from the base station. The terminal can blind decode the DCI format 1_0 with CRC scrambled with the C-RNTI value in the search space.

[0380] In the third step (1520), it can be determined whether all FDRA fields of the DCI format received by the terminal are '1'. If all are '1', it can be determined that the DCI format indicates a PDCCH order. If not all are '1', it can be determined that the DCI format schedules a PDSCH.

[0381] In step 4 (1530), the terminal can acquire a RACH opportunity type indicator from DCI format 1_0. The RACH opportunity type indicator can be 1 bit or 2 bits. Depending on the RACH opportunity type indicator, the type of RACH opportunity in which the PRACH preamble can be transmitted can be indicated. If it is 1 bit, the RACH opportunity in which the PRACH preamble can be transmitted can be indicated as one of the first valid RACH opportunity and the second valid RACH opportunity. If it is 2 bits, the RACH opportunity in which the PRACH preamble can be transmitted can be indicated as one of the first valid RACH opportunity and the second valid RACH opportunity, or both types.

[0382] In step 5 (1540), the terminal can transmit a PRACH preamble in a RACH opportunity of a type corresponding to the RACH opportunity type indicator.

[0383] <Example 2: Instructions using DCI monitoring information>

[0384] In a second embodiment of the present disclosure, a terminal can determine a type based on configuration information for monitoring DCI. Here, the configuration information for monitoring DCI may include at least one of a search space configuration, a DCI payload size, an RNTI value, and a DCI format.

[0385] More specifically, the terminal may be configured with a first search space for receiving a PDCCH order indicating PRACH preamble transmission in first valid RACH opportunities, and a second search space for receiving a PDCCH order indicating PRACH preamble transmission in second valid RACH opportunities. That is, when the terminal receives DCI format 1_0 indicating a PDCCH order in the first search space, the terminal may determine that the PDCCH order is a PDCCH order indicating PRACH preamble transmission in the first valid RACH opportunities. When the terminal receives DCI format 1_0 indicating a PDCCH order in the second search space, the terminal may determine that the PDCCH order is a PDCCH order indicating PRACH preamble transmission in the second valid RACH opportunities.

[0386] The payload size and RNTI value of DCI format 1_0 indicating the PDCCH order corresponding to the first valid RACH opportunities and the payload size and RNTI value of DCI format 1_0 indicating the PDCCH order corresponding to the second valid RACH opportunities may be different from each other. For example, the payload size of DCI format 1_0 indicating the PDCCH order corresponding to the second valid RACH opportunities may be set by the base station or defined as 1 bit larger or smaller than the payload size of DCI format 1_0 indicating the PDCCH order corresponding to the first valid RACH opportunities. The RNTI value of DCI format 1_0 indicating the PDCCH order corresponding to the second valid RACH opportunities may use a value other than C-RNTI, and the RNTI value may be set by the base station.

[0387] The terminal may be indicated the PDCCH order corresponding to the first valid RACH opportunities through DCI format 1_0, and the PDCCH order corresponding to the second valid RACH opportunities may be indicated through DCI format 0_0. That is, if the terminal receives the DCI format 0_0 in which the CRC is scrambled with the C-RNTI, and all FDRA fields of the DCI format are '1', the terminal may determine that the DCI format 0_0 indicates the PDCCH order of the second valid RACH opportunities. The DCI format may include the same fields as Table X1.

[0388] <Example 3: Instruction via PRACH Mask index>

[0389] The terminal can be instructed to select one of the 16 PRACH Mask index rows in Table 18 through the PRACH Mask index field. In Table 18, indices 0 to 10 are defined, but indices 11 to 15 are reserved.

[0390] In a first method, the terminal may apply indices 0 to 10 to the first valid RACH opportunity and indices 11 to 15 to the second valid RACH opportunity. If one of the rows of indices 11 to 15 is indicated, transmission of the second valid RACH opportunities may be permitted. To apply indices 11 to 15 to the second valid RACH opportunity, a new operation may be defined for indices 11 to 15.

[0391] More specifically, indices 11 to 15 may include at least up to five pieces of information from the following:

[0392] - All second valid RACH opportunities

[0393] - Second valid RACH opportunity with index 1

[0394] - Second valid RACH opportunity with index 2

[0395] - Second valid RACH opportunity with index 3

[0396] - Second valid RACH opportunity with index 4

[0397] - Second valid RACH opportunity with index 5

[0398] - Second valid RACH opportunity with index 6

[0399] - Second valid RACH opportunity with index 7

[0400] - Second valid RACH opportunity with even index

[0401] - Second valid RACH opportunity with odd index

[0402] - Second valid RACH opportunity with index 1 or 5

[0403] - Second valid RACH opportunity with index 2 or 6

[0404] - Second valid RACH opportunity with index 3 or 7

[0405] - Second valid RACH opportunity with index 4 or 8

[0406] For example, five rows can be selected as follows:

[0407] - Row 11: All second valid RACH opportunities

[0408] - Row 12: Second valid RACH opportunity with index 1 or 5

[0409] - Row 13: Second valid RACH opportunity with index 2 or 6

[0410] - Row 14: Second valid RACH opportunity with index 3 or 7

[0411] - Row 15: Second valid RACH opportunity with index 4 or 8

[0412] In a second method, the terminal may apply indices 0 to 10 to the first valid RACH opportunity, and indices 11 to 15 to the first and second valid RACH opportunities. If one of the rows of indices 11 to 15 is indicated, transmission of the first and second valid RACH opportunities may be permitted. In order to apply indices 11 to 15 to the first and second valid RACH opportunities, a new operation may be defined for indices 11 to 15.

[0413] More specifically, indices 11 to 15 may include at least up to five pieces of information from the following:

[0414] - All first valid RACH opportunities and all second valid RACH opportunities

[0415] - The first valid RACH opportunity with an index of 1 and the second valid RACH opportunity

[0416] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 2

[0417] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 3

[0418] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 4

[0419] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 5

[0420] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 6

[0421] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 7

[0422] - The first valid RACH opportunity and the second valid RACH opportunity with an even index

[0423] - The first valid RACH opportunity and the second valid RACH opportunity with odd indices

[0424] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 1 or 5.

[0425] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 2 or 6.

[0426] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 3 or 7.

[0427] - The first valid RACH opportunity and the second valid RACH opportunity with an index of 4 or 8.

[0428] Note that the first and second methods can be applied simultaneously. That is, some of the rows from index rows 10 to 15 may include operations of the rows of the first method, and the remaining rows may include operations of the rows of the second method.

[0429] <Example 4: Instruction via SS / PBCH index>

[0430] In this disclosure, two types of RACH opportunities are mapped to a single SS / PBCH. When determining a RACH opportunity that allows PRACH preamble transmission in a PDCCH order, only one of the two types of RACH opportunities mapped to a single SS / PBCH can be used. That is, for a PDCCH order, only one type of RACH opportunity can be applied to a single SS / PBCH.

[0431] More specifically, let's say that the index of SS / PBCH is 0 to 63. The terminal can be configured with the type of RACH opportunity corresponding to each SS / PBCH for the PDCCH order from the base station. For example, the first valid RACH opportunity can be configured to be mapped to the SS / PBCH index '0', and the second valid RACH opportunity can be configured to be mapped to the SS / PBCH index '1'. The terminal can be indicated with the SS / PBCH index through the SS / PBCH index field. One type of RACH opportunity can be mapped to the SS / PBCH corresponding to the SS / PBCH index. For example, if the terminal is indicated with '0' in the SS / PBCH index field, it can be determined that PRACH preamble transmission is allowed in the first valid RACH opportunity mapped to the SS / PBCH with the index 0. When the terminal is indicated with '1' in the SS / PBCH index field, it can be determined that PRACH preamble transmission is allowed in the second valid RACH opportunity mapped to the SS / PBCH with index 1.

[0432] The type of RACH opportunity mapped to the SS / PBCH index can be determined as follows.

[0433] - The base station can indicate to the terminal the type of RACH opportunity corresponding to each index. That is, it can set whether the first valid RACH opportunity or the second RACH opportunity is mapped to SS / PBCH index 'n'. This can be set with 1 bit per SS / PBCH index.

[0434] - The base station can indicate to the terminal the SS / PBCH indices to which the second valid RACH opportunities are mapped. That is, the base station can indicate the SS / PBCH indices to which the second RACH opportunities are mapped, for example, 0, 2, 4, and 8, and the terminal can determine that the SS / PBCHs with indices 0, 2, 4, and 8 are mapped to the second valid RACH opportunities. The SS / PBCHs with other indices can be determined to be mapped to the first valid RACH opportunities.

[0435] - The base station can indicate to the terminal the SS / PBCH indices to which the first valid RACH opportunity is mapped. That is, the base station can indicate the SS / PBCH indices to which the first RACH opportunity is mapped, for example, 1, 3, 5, and 7, and the terminal can determine that the SS / PBCHs with indices 1, 3, 5, and 7 are mapped to the first valid RACH opportunities. The SS / PBCHs with other indices can be determined to be mapped to the second valid RACH opportunities.

[0436] - The terminal can determine the mapping based on the type of symbol in which the SS / PBCH is received without separate instructions from the base station. If the SS / PBCH is received in a symbol for which SBFD resources are configured, the terminal can assume that the second valid RACH opportunity is mapped to the SS / PBCH. If the SS / PBCH is received in a symbol for which SBFD resources are not configured, the terminal can assume that the first valid RACH opportunity is mapped to the SS / PBCH.

[0437] In the embodiment of the present disclosure, only one type of RACH opportunity is mapped according to the SS / PBCH index, but only one type of RACH opportunity can be mapped to every SS / PBCH index. That is, the PDCCH order can always allow PRACH preamble transmission only in one type of RACH opportunity. For example, in the case of an SBFD terminal, it can be assumed that the PDCCH order always allows PRACH preamble transmission only in the second type RACH opportunities. For example, even in the case of an SBFD terminal, it can be assumed that the PDCCH order always allows PRACH preamble transmission only in the first type RACH opportunities. For example, the base station can instruct / configure the terminal through the PDCCH order whether PRACH preamble transmission is possible only in the first type RACH opportunities or in the second type RACH opportunities. Additionally, the base station can instruct / configure the terminal to enable PRACH preamble transmission in Type 1 RACH opportunities and Type 2 RACH opportunities through the PDCCH order. In this case, the above-described first embodiment to the fourth embodiment can be applied.

[0438] <Example 5: Decision based on reception of PDCCH order>

[0439] According to one embodiment of the present disclosure, a terminal may determine one type of RACH opportunities based on the reception time of a PDCCH order. Here, the reception time may refer to at least one of the start symbol and the end symbol of a PDCCH transmitting the PDCCH order. The terminal may transmit a PRACH preamble belonging to one of the determined types of RACH opportunities.

[0440] The terminal can determine the nearest RACH opportunity after receiving the PDCCH order. For example, if the nearest RACH opportunity after receiving the PDCCH order is determined to be of type 1, the terminal can determine that the PDCCH order indicates that a PRACH preamble can be transmitted in type 1 RACH opportunities. Accordingly, the PRACH preamble transmitted from the PDCCH order can belong to type 1 RACH opportunities.

[0441] The terminal can determine the nearest RACH opportunity after N symbols from the time of receiving the PDCCH order. For example, if the nearest RACH opportunity after N symbols from the time of receiving the PDCCH order is determined to be of the first type, the terminal can determine that the PDCCH order indicates that a PRACH preamble can be transmitted in the first type RACH opportunities. Accordingly, the PRACH preamble transmitted from the PDCCH order may belong to the first type RACH opportunities. Here, N symbols may be the time taken to decode the PDCCH transmitting the PDCCH order. For example, the number of symbols may vary depending on the subcarrier spacing. Alternatively, the number of symbols may be 14 symbols (i.e., 1 slot) or an integer multiple of the number.

[0442] Alternatively, the terminal may determine one type of RACH opportunities based on at least one of the index of the RB that received the PDCCH order, the index of the CCE, the index of the CORESET, the index of the CORESET pool, the index of the search space, and the PDCCH index. Here, the index of the RB may be the index of the RB with the lowest frequency axis occupied by the PDCCH that received the PDCCH order. Here, the index of the CCE may be the lowest index among the indices of the CCEs that are occupied by the PDCCH that received the PDCCH order.

[0443] The terminal can determine a type of RACH opportunity based on the above indices. For example, if the index is an even number (0, 2, 4, ...), it can be determined that the first type of RACH opportunity is indicated, and if the index is an odd number (1, 3, 5, ...), it can be determined that the second type of RACH opportunity is indicated. Alternatively, if the index is less than a certain value, it can be determined that the first type of RACH opportunity is indicated, and if it is greater than a certain value, it can be determined that the second type of RACH opportunity is indicated.

[0444] FIG. 16 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0445] Referring to FIG. 16, the terminal may include a transceiver, which refers to a terminal receiving unit (1600) and a terminal transmitting unit (1610), a memory (not shown), and a terminal processing unit (1605, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver units (1600, 1610), the memory, and the terminal processing unit (1605) of the terminal may operate. The terminal processing unit (1605, or processor) may control the operation of the terminal according to each of the above-described embodiments as well as a combination of at least one embodiment. 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, the memory, and the processor may be implemented in the form of a single chip.

[0446] A transceiver unit can transmit and receive signals to and from a base station. The signals may include control information and data. To this end, the transceiver unit may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver unit, and the components of the transceiver unit are not limited to the RF transmitter and RF receiver.

[0447] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit a signal output from the processor through the wireless channel.

[0448] Memory can store programs and data necessary for the terminal's operation. Furthermore, memory can store control information or data included in signals transmitted and received by the terminal. Memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0449] Additionally, the processor can control a series of processes to enable the terminal to operate according to the aforementioned embodiments. For example, the processor can receive DCI consisting of two layers and control components of the terminal to simultaneously receive multiple PDSCHs. There may be multiple processors, and the processors can perform terminal component control operations by executing programs stored in memory.

[0450] FIG. 17 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0451] Referring to FIG. 17, the base station may include a transceiver, which refers to a base station receiver (1700) and a base station transmitter (1710), a memory (not shown), and a base station processor (1705, or base station control unit or processor). According to the communication method of the base station described above, the transceiver (1700, 1710), the memory, and the base station processor (1705) of the base station may operate. The base station processor (1705, or processor) may control the operation of the base station according to each of the above embodiments as well as a combination of at least one embodiment. However, the components of the base station are not limited to the above examples. For example, the base station may include more or fewer components than the above-described components. In addition, the transceiver, the memory, and the processor may be implemented in the form of a single chip.

[0452] The transceiver can transmit and receive signals with the terminal. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0453] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit the signal output from the processor through the wireless channel.

[0454] The memory can store programs and data necessary for the operation of the base station. Furthermore, the memory can store control information or data included in signals transmitted and received by the base station. The memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0455] The processor can control a series of processes to enable the base station to operate according to the embodiments of the present disclosure described above. For example, the processor can configure two layers of DCIs containing allocation information for multiple PDSCHs and control each component of the base station to transmit them. There may be multiple processors, and the processors can perform component control operations of the base station by executing programs stored in memory.

[0456] 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.

[0457] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. The one or more programs include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of the present disclosure.

[0458] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc ROM (CD-ROM), digital versatile discs (DVDs) or other forms of optical storage device, magnetic cassette. Or, they may be stored in a memory configured as a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0459] Additionally, the program may be stored on an attachable storage device that is accessible via a communication network, such as the Internet, an intranet, a local area network (LAN), a wide local area network (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device performing an embodiment of the present disclosure.

[0460] In the specific embodiments of the present disclosure described above, components included in the invention are expressed in the singular or plural form, depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in the plural form may be composed of singular elements, or components expressed in the singular form may be composed of plural elements.

[0461] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are only specific examples to easily explain the technical contents of the present disclosure and help understand the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, the above-mentioned embodiments can be combined and operated with each other as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment can be combined with each other to operate a base station and a terminal. For example, parts of the first embodiment and the second embodiment of the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above-mentioned embodiments have been presented based on an FDD LTE system, other modifications based on the technical idea of ​​the above-mentioned embodiments can be implemented with other systems such as a TDD LTE system, 5G, or NR system.

[0462] 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.

[0463] 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.

[0464] 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.

Claims

1. In a method performed by a terminal (user equipment) in a wireless communication system, A step of receiving, from a base station, first RACH (random access channel) configuration information associated with TDD (time division duplex) and second RACH configuration information associated with SBFD (subband full duplex); A step of identifying a first RACH opportunity mapped to a synchronization signal block (SSB) according to the first RACH configuration information and a second RACH opportunity mapped to the SSB according to the second RACH configuration information; A step of receiving, from the base station, downlink control information (DCI) including information for identifying either the first RACH opportunity or the second RACH opportunity; and A method comprising the step of transmitting, to the base station, a preamble for contention-free random access (CFRA) at a RACH opportunity indicated by the information.

2. In claim 1, The first RACH opportunity is identified based on the first mapping-related configuration information included in the first RACH configuration information, The second RACH opportunity is identified based on the second mapping-related configuration information included in the second RACH configuration information, A method wherein the first RACH opportunity and the second RACH opportunity are identified separately.

3. In claim 1, The above DCI includes a PDCCH (physical downlink control channel) order for the above CFRA, A method wherein the information included in the DCI is 1 bit.

4. In claim 1, The above first RACH opportunity is located within the uplink symbol of TDD, The above second RACH opportunity is located within the SBFD symbol.

5. In a wireless communication system, in the terminal (user equipment), transceiver; and including a controller coupled with the above transmitter and receiver, The above controller, Receive, from a base station, first RACH (random access channel) configuration information associated with TDD (time division duplex) and second RACH configuration information associated with SBFD (subband full duplex), Identifying a first RACH opportunity mapped to a SSB (synchronization signal block) according to the first RACH configuration information and a second RACH opportunity mapped to the SSB according to the second RACH configuration information; Receive, from the base station, downlink control information (DCI) including information for identifying either the first RACH opportunity or the second RACH opportunity, A terminal configured to transmit a preamble for contention-free random access (CFRA) to the base station at a RACH opportunity indicated by the information.

6. In claim 5, The first RACH opportunity is identified based on the first mapping-related configuration information included in the first RACH configuration information, The second RACH opportunity is identified based on the second mapping-related configuration information included in the second RACH configuration information, A terminal wherein the first RACH opportunity and the second RACH opportunity are each separately identified.

7. In claim 5, The above DCI includes a PDCCH (physical downlink control channel) order for the above CFRA, The terminal, wherein the information included in the DCI is 1 bit.

8. In claim 5, The above first RACH opportunity is located within the uplink symbol of TDD, The above second RACH opportunity is located within the SBFD symbol, the terminal.

9. In a method performed by a base station in a wireless communication system, A step of transmitting, to a terminal (user equipment), first RACH (random access channel) configuration information associated with TDD (time division duplex) and second RACH configuration information associated with SBFD (subband full duplex); A step of transmitting, to the terminal, DCI (downlink control information) including information for identifying either a first RACH opportunity or a second RACH opportunity; and A step of receiving a preamble for contention-free random access (CFRA) at a RACH opportunity indicated by the information from the terminal, The above first RACH opportunity is associated with the above first RACH configuration information, A method wherein the second RACH opportunity is associated with the second RACH configuration information.

10. In claim 9, The above first RACH opportunity is associated with the first mapping-related configuration information included in the above first RACH configuration information, The second RACH opportunity is associated with the second mapping-related configuration information included in the second RACH configuration information, A method wherein the first RACH opportunity and the second RACH opportunity are identified separately.

11. In claim 9, The above DCI includes a PDCCH (physical downlink control channel) order for the above CFRA, A method wherein the information included in the DCI is 1 bit.

12. In claim 9, The above first RACH opportunity is located within the uplink symbol of TDD, The above second RACH opportunity is located within the SBFD symbol.

13. In a wireless communication system, at a base station, transceiver; and including a controller coupled with the above transmitter and receiver, The above controller, Transmitting, to a terminal (user equipment), first RACH (random access channel) configuration information associated with TDD (time division duplex) and second RACH configuration information associated with SBFD (subband full duplex), Transmitting to the terminal, DCI (downlink control information) including information for identifying either the first RACH opportunity or the second RACH opportunity, From the terminal, a preamble for contention-free random access (CFRA) is set to be received at a RACH opportunity indicated by the information, The above first RACH opportunity is associated with the above first RACH configuration information, The above second RACH opportunity is associated with the above second RACH configuration information, the base station.

14. In claim 13, The above first RACH opportunity is associated with the first mapping-related configuration information included in the above first RACH configuration information, The second RACH opportunity is associated with the second mapping-related configuration information included in the second RACH configuration information, A base station, wherein the first RACH opportunity and the second RACH opportunity are each separately identified.

15. In claim 13, The above DCI includes a PDCCH (physical downlink control channel) order for the above CFRA, The base station, wherein the information included in the DCI is 1 bit.

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