Method and apparatus for transmission and reception of network control repeater for wireless communication system

Abstract

A method performed by a network control relay (NCR) in a wireless communication system is provided. The method includes: receiving control information from a base station, the control information including information associated with cancellation and retransmission of an uplink transmission of an NCR; identifying a first duration for cancellation of the uplink transmission based on the control information; cancelling the uplink transmission for the first duration; identifying a second duration for re-transmission of the uplink transmission cancelled within the first duration; and performing retransmission of the uplink transmission based on the second duration.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly to a method and device for transmitting and receiving a network-controlled repeater in a wireless communication system. Background Art

[0002] The fifth generation (5G) mobile communication technology defines a wide frequency band, making high transmission rates and new services possible, and can be implemented not only in "6 gigahertz (GHz) below" frequency bands such as 3.5 GHz, but also in "6 GHz above" frequency bands (including 28 GHz and 39 GHz) called millimeter waves (mmWave). In addition, the implementation of the sixth generation (6G) mobile communication technology (called a super 5G system) in the terahertz (THz) frequency band (e.g., 95 GHz to 3 THz frequency band) has been considered to achieve a transmission rate fifty times faster than that of the 5G mobile communication technology and an ultra-low latency that is one-tenth of that of the 5G mobile communication technology.

[0003] At the beginning of the development of 5G mobile communication technology, in order to support services and meet the performance requirements related to enhanced mobile broadband (eMBB), ultra-reliable and low-latency communications (URLLC) and massive machine type communications (mMTC), standardization of the following technologies has been ongoing: beamforming and massive multiple-input multiple-output (MIMO) to mitigate radio wave path loss in millimeter waves and increase radio wave transmission distance; parameter sets that support dynamic operation of millimeter wave resources and time slot formats for efficient use (e.g., operating multiple subcarrier spacings); initial access technology for supporting multi-beam transmission and broadband; definition and operation of bandwidth parts (BWPs); new channel coding methods, such as low-density parity-check (LDPC) codes for large amounts of data transmission and polarization codes for highly reliable transmission of control information; L2 preprocessing; and network slicing for providing dedicated networks dedicated to specific services.

[0004] Currently, in view of the services supported by 5G mobile communication technology, discussions on the improvement and performance enhancement of initial 5G mobile communication technology are ongoing, and there is already physical layer standardization on technologies such as: Vehicle-to-Everything (V2X) for assisting driving decisions of autonomous vehicles based on information about the location and status of the vehicle sent by the vehicle and for improving user convenience; New Radio Unlicensed (NR-U) for system operation designed to comply with various regulatory requirements in unlicensed bands; New Radio (NR) User Equipment (UE) energy saving; Non-Terrestrial Network (NTN), which is UE-satellite direct communication for providing coverage in areas where terrestrial network communications are not available; and positioning.

[0005] In addition, standardization is ongoing in air interface architecture / protocols for technologies such as the following: Industrial Internet of Things (IIoT) for supporting new services through interworking and integration with other industries; Integrated Access and Backhaul (IAB) for providing nodes for network service area expansion by supporting wireless backhaul links and access links in an integrated manner; Mobility enhancements including conditional switching and dual active protocol stack (DAPS) switching; and two-step random access (2-step random access channel (RACH) for NR) for simplifying the random access process. Standardization is also ongoing in system architecture / services for the following technologies: 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software defined network (SDN) technologies; and mobile edge computing (MEC) for receiving services based on UE location.

[0006] With the commercialization of 5G mobile communication systems, the number of connected devices, which has been growing exponentially, will be connected to the communication network, and it is therefore expected that there will be a need to enhance the functions and performance of 5G mobile communication systems and the integrated operation of connected devices. To this end, new research related to the following technologies is planned: Extended Reality (XR) to effectively support Augmented Reality (AR), Virtual Reality (VR), Mixed Reality (MR), etc.; Improve 5G performance and reduce complexity by utilizing Artificial Intelligence (AI) and Machine Learning (ML); AI service support; Virtual Reality service support and drone communication.

[0007] In addition, such developments in 5G mobile communication systems will serve not only as a basis for developing the following technologies: new waveforms for providing coverage in the terahertz band for 6G mobile communication technology; multi-antenna transmission technologies such as full-dimensional MIMO (FD-MIMO), array antennas, and large antennas; metamaterial-based lenses and antennas for improving the coverage of terahertz band signals; high-dimensional spatial multiplexing technology using orbital angular momentum (OAM); and reconfigurable smart surfaces (RIS), but will also serve as a basis for developing the following technologies: full-duplex technology for increasing the frequency efficiency of 6G mobile communication technology and improving system networks; AI-based communication technology for achieving system optimization by leveraging satellites and AI from the design stage and internalizing end-to-end AI support functions; and next-generation distributed computing technology for implementing services at a complexity level that exceeds the limits of UE operating capabilities by utilizing ultra-high-performance communication and computing resources.

[0008] The above information is presented only as background information to assist in understanding the present disclosure. No determination has been made, and no assertion has been made, as to whether any of the above items may be used as prior art for the present disclosure. Summary of the invention

[0009] [Technical issues]

[0010] An aspect of the present disclosure is to solve at least the above problems and / or disadvantages and to provide at least the advantages described below. Therefore, an aspect of the present disclosure is to provide a method for performing uplink or downlink communication between a base station and a terminal through a relay in a wireless communication system.

[0011] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0012] [Technical solution]

[0013] According to one aspect of the present disclosure, a method performed by a network controlled repeater (NCR) in a wireless communication system is provided. The method includes: receiving control information from a base station, the control information including information associated with cancellation and retransmission of uplink transmission of the NCR; identifying a first duration for cancellation of uplink transmission based on the control information; canceling the uplink transmission within the first duration; identifying a second duration for retransmission of the uplink transmission canceled within the first duration; and performing retransmission of the uplink transmission based on the second duration.

[0014] According to another aspect of the present disclosure, a method performed by a base station in a wireless communication system is provided. The method includes: transmitting control information to an NCR, the control information including information associated with cancellation and retransmission of uplink transmission of the NCR; and receiving an uplink signal from the NCR based on a first duration, wherein the uplink transmission of the NCR is canceled within a second duration for cancellation of the uplink transmission, the second duration is identified based on the control information, and wherein the uplink signal corresponds to the retransmission of the uplink transmission canceled within the second duration.

[0015] According to another aspect of the present disclosure, an NCR in a wireless communication system is provided. The NCR includes a transceiver and a controller, the controller being coupled to the transceiver and configured to: receive control information from a base station, the control information including information associated with cancellation and retransmission of uplink transmission of the NCR; identify a first duration for cancellation of uplink transmission based on the control information; cancel the uplink transmission within the first duration; identify a second duration for retransmission of the uplink transmission canceled within the first duration; and perform retransmission of the uplink transmission based on the second duration.

[0016] According to another aspect of the present disclosure, a base station in a wireless communication system is provided. The base station includes a transceiver and a controller, the controller being coupled to the transceiver and configured to: transmit control information to an NCR, the control information including information associated with cancellation and retransmission of uplink transmission of the NCR; and receive an uplink signal from the NCR based on a first duration, wherein the uplink transmission of the NCR is canceled within a second duration for cancellation of the uplink transmission, the second duration being identified based on the control information, and wherein the uplink signal corresponds to the retransmission of the uplink transmission canceled within the second duration.

[0017] The technical problems to be achieved in the embodiments of the present disclosure are not limited to the above-mentioned technical problems, and other technical problems not mentioned herein will be clearly understood by those skilled in the art to which the present disclosure belongs from the following description.

[0018] [Beneficial Effects of the Invention]

[0019] According to an embodiment of the present disclosure, a repeater under the control of a base station can amplify and transmit an uplink signal transmitted from a terminal to the base station through the repeater, and transmit the uplink signal transmitted by the repeater to the base station by performing time multiplexing in a wireless communication system.

[0020] Other aspects, advantages, and salient features of the disclosure will be apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0022] Figure 1 The basic structure of time-frequency resources of a wireless communication system according to an embodiment of the present disclosure is shown;

[0023] Figure 2 The frame, subframe and time slot structure of a wireless communication system according to an embodiment of the present disclosure are shown;

[0024] Figure 3 An example of a bandwidth part (BWP) configuration in a wireless communication system according to an embodiment of the present disclosure is shown;

[0025] Figure 4 The structure of a downlink control channel of a wireless communication system according to an embodiment of the present disclosure is shown;

[0026] Figure 5An example of frequency domain resource allocation of a physical downlink shared channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure is shown;

[0027] Figure 6 An example of time domain resource allocation of a PDSCH in a wireless communication system according to an embodiment of the present disclosure is shown;

[0028] Figure 7 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 is shown;

[0029] Figure 8 is a view showing a method of configuring a semi-static hybrid automatic repeat request (HARQ)-acknowledgement (ACK) codebook in an NR system according to an embodiment of the present disclosure;

[0030] Fig. 9 is a diagram illustrating a method for configuring a dynamic HARQ-ACK codebook in an NR system according to an embodiment of the present disclosure;

[0031] Fig.10 is a view showing a method for configuring HARQ-ACK codebook retransmission in an NR system according to an embodiment of the present disclosure;

[0032] Fig.11 An example of an uplink-downlink configuration (UL / DL configuration) in a 5G system according to an embodiment of the present disclosure is shown;

[0033] Fig.12 An example of transmission and reception related to NCR when NCR is relayed between a base station and a terminal according to an embodiment of the present disclosure is shown;

[0034] Fig.13 An example of uplink transmission according to a radio frequency (RF) chain when an NCR is relayed between a base station and a terminal according to an embodiment of the present disclosure is shown;

[0035] Fig.14 An example of a case where an NCR dedicated time slot is configured by a high-layer signaling according to an embodiment of the present disclosure is shown;

[0036] Fig.15 An example of operations 2-1 and 2-2 in method 3 according to an embodiment of the present disclosure is shown;

[0037] Fig.16 An example of an uplink-downlink configuration of an NCR according to an embodiment of the present disclosure is shown;

[0038] Fig.17An example of configuring an uplink-downlink switching time point of an NCR according to an embodiment of the present disclosure is shown;

[0039] Fig.18 A flowchart illustrating the operation of the NCR according to an embodiment of the present disclosure;

[0040] Fig.19 is a diagram showing a terminal structure in a wireless communication system according to an embodiment of the present disclosure; and

[0041] Fig. 20 is a view showing a structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0042] Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. DETAILED DESCRIPTION

[0043] The following description is provided with reference to the accompanying drawings to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. The following description includes various specific details that are helpful for understanding, but these should be considered as exemplary only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and conciseness, descriptions of well-known functions and structures may be omitted.

[0044] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and is not intended to limit the present disclosure as defined by the appended claims and their equivalents.

[0045] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0046] In the accompanying drawings, some elements may be exaggerated, omitted or schematically shown. In addition, the size of each element does not fully reflect the actual size. In the accompanying drawings, the same or corresponding elements have the same reference numerals.

[0047] By referring to the embodiments described in detail below in conjunction with the accompanying drawings, the advantages and features of the present disclosure and the methods for achieving them will become apparent. However, the present disclosure is not limited to the embodiments set forth below, but can be implemented in various different forms. The following embodiments are provided only to fully disclose the present disclosure and inform those skilled in the art of the scope of the present disclosure, and the present disclosure is limited only by the scope of the attached claims. Throughout the entire specification, the same or similar reference numerals represent the same or similar elements.

[0048] In this article, it should be understood that each box of the flowchart diagram and the box combination in the flowchart diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device create a device for implementing the functions specified in one or more flowchart boxes. These computer program instructions can also be stored in a computer-usable or computer-readable memory, which can instruct the computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-usable or computer-readable memory produce an article including an instruction device, which implements the functions specified in the one or more flowchart boxes. Computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are performed on a computer or other programmable device, thereby generating a computer-implemented process, so that the instructions executed on a computer or other programmable device provide steps for implementing the functions specified in one or more flowchart boxes.

[0049] In addition, each frame of the flowchart diagram can represent a module, a code segment or a code portion, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions mentioned in the frame may not occur in order. For example, depending on the functionality involved, two frames shown in succession can actually be executed roughly at the same time, or these frames can sometimes be executed in reverse order.

[0050] As used herein, "unit" refers to a software element or hardware element that performs a predetermined function, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC). However, a unit does not always have the meaning that is limited to software or hardware. A "unit" can be constructed to be stored in an addressable storage medium or to execute one or more processors. Therefore, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" can be combined into a smaller number of elements or "units", or divided into a larger number of elements or "units". In addition, elements and units can be implemented as one or more central processing units (CPUs) in a reproduction device or a secure multimedia card. In addition, a "unit" in an embodiment can include one or more processors.

[0051] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. When describing the present disclosure, when it is determined that the description may make the subject matter of the present disclosure unnecessarily unclear, the detailed description of the known functions or configurations combined herein will be omitted. The terms to be described below are terms defined in consideration of the functions in the present disclosure, and may be different according to the user, the user's intention or habit. Therefore, the definition of the term should be determined based on the content throughout the entire specification. In the following description, a base station is an entity that allocates resources to a terminal, and may be at least one of a next generation node (gNode B), an evolved node B (eNode B), a node B, a base station (BS), a wireless access unit, a base station controller, and a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. Of course, the examples of base stations and terminals are not limited thereto. The following description of the present disclosure relates to a technology for receiving broadcast information from a base station by a terminal in a wireless communication system. The present disclosure relates to a communication technology and a system thereof for integrating IoT technology with a fifth generation (5G) communication system designed to support a higher data transfer rate than a fourth generation (4G) system. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail business, safety and security-related services, etc.).

[0052] In the following description, for the sake of convenience, terms referring to broadcast information, terms related to communication coverage, terms referring to state changes (e.g., events), terms referring to network entities, terms referring to messages, terms referring to device elements, etc. are exemplarily used. Therefore, the present disclosure is not limited to the terms used below, and other terms referring to subjects with equivalent technical meanings may be used.

[0053] In the following description, some terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard may be used for convenience of description. However, the present disclosure is not limited to these terms and names and can be applied to systems conforming to other standards in the same manner.

[0054] Wireless communication systems have evolved from early-stage wireless communication systems that provided voice-centric services to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards such as High Speed ​​Packet Access (HSPA), 3GPP's Long Term Evolution (LTE or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced (LTE-A) and LTE-Pro, 3GPP2's High Rate Packet Data (HRPD) and Ultra Mobile Broadband (UMB), the Institute of Electrical and Electronics Engineers (IEEE)'s 802.16e, and the like.

[0055] The LTE system, which is a representative example of a broadband wireless communication system, has adopted an orthogonal frequency division multiplexing (OFDM) scheme in a downlink (DL) and has adopted a single carrier frequency division multiple access (SC-FDMA) scheme in an uplink (UL). UL refers to a wireless link through which a terminal (user equipment (UE) or mobile station (MS)) transmits data or a control signal to a base station (BS or eNodeB), and DL refers to a wireless link through which a base station transmits data or a control signal to a terminal. The multiple access scheme generally allocates and operates time-frequency resources for transmitting data or control information according to each user so as to prevent the time-frequency resources from overlapping each other, that is, to establish orthogonality, thereby distinguishing the data or control information of each user.

[0056] As a future communication system after LTE, that is, a 5G communication system must be able to freely reflect the various needs of users and service providers, and therefore needs to support services that meet various needs. The services considered by the 5G communication system include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable low latency communication (URLLC), etc.

[0057] According to some embodiments, eMBB is intended to provide a data transmission rate higher than that supported by LTE, LTE-A or LTE-Pro. For example, in a 5G communication system, from the perspective of a base station, eMBB should be able to provide a peak data rate of 20Gbps in DL and a peak data rate of 10Gbps in UL. At the same time, the 5G communication system should provide an increased user-perceived data rate of the terminal. In order to meet such needs, it is necessary to improve various transmission / reception technologies, including further improved multiple-input multiple-output (MIMO) transmission technology. In addition, the 5G communication system uses a bandwidth wider than 20 megahertz (MHz) in a frequency band of 3GHz to 6GHz or more than 6GHz (rather than the 2GHz band used by the current LTE), thereby meeting the data transmission rate required in the 5G communication system.

[0058] Meanwhile, mMTC is considered to support application services such as the Internet of Things (IoT) in the 5G communication system. mMTC is required for access support of large-scale terminals in a cell, coverage enhancement of terminals, improved battery time, and cost reduction of terminals in order to effectively provide IoT. IoT needs to be able to support a large number of terminals (e.g., 1,000,000 terminals / km) in a cell because it is attached to various sensors and devices to provide communication functions. 2 ). In addition, since the terminal supporting mMTC is likely to be located in a shadow area not covered by the cell, such as in the basement of a building due to the nature of the service, the terminal requires a wider coverage area than other services provided by the 5G communication system. The terminal supporting mMTC should be configured as an inexpensive terminal and requires a very long battery life because the battery of the terminal is difficult to replace frequently.

[0059] Finally, URLLC is a cellular-based wireless communication service for mission-critical purposes, and URLLC can be considered for services such as remote control of robots or mechanical devices, industrial automation, drones, remote health care, emergency notifications, etc. Therefore, URLLC should provide very low latency and very high reliability. For example, services supporting URLLC need to meet an air interface latency of less than 0.5 milliseconds and include support for 10 -5 or smaller packet error rate. Therefore, for services supporting URLLC, the 5G system should provide a shorter transmission time interval (TTI) than other services, while ensuring the design requirements of allocating a wide range of resources in the frequency band. However, the above-mentioned mMTC, URLLC and eMBB are only examples of different service types, and the service types to which the present disclosure is applied are not limited to the above-mentioned examples.

[0060] The services discussed above considered in the 5G communication system should be integrated with each other and provided based on a single framework. That is, for efficient resource management and control, it is expected to control and transmit such services by integrating them into one system rather than operating them separately.

[0061] In addition, although the embodiments of the present disclosure will be described below using LTE, LTE-A, LTE Pro or NR systems as examples, the embodiments of the present disclosure can be applied to other communication systems with similar technical backgrounds or channel types. In addition, the embodiments of the present disclosure can be applied to other communication systems by making some modifications within the scope determined by a technician with technical knowledge that does not significantly deviate from the scope of the present disclosure.

[0062] 5G system framework

[0063] Hereinafter, the framework structure of the 5G system will be described in more detail with reference to the accompanying drawings.

[0064] Figure 1 The basic structure of time-frequency resources of a wireless communication system according to an embodiment of the present disclosure is shown.

[0065] refer to Figure 1 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time-frequency domain may be a resource element (RE) 1-01. The resource element 1-01 may be defined by 1 orthogonal frequency division multiplexing (OFDM) symbol 1-02 on the time axis and by 1 subcarrier 1-03 on the frequency axis. In the frequency domain, (For example, 12) consecutive REs may configure one resource block (RB) 1-04. In an embodiment, a plurality of OFDM symbols may configure one subframe 1-10.

[0066] Figure 2 The frame, subframe and time slot structures in a wireless communication system according to an embodiment of the present disclosure are shown.

[0067] refer to Figure 2 , one frame 2-00 may be configured by one or more subframes 2-01, and one subframe may include one or more time slots 2-02. For example, one frame 2-00 may be defined as 10 milliseconds (ms). One subframe 2-01 may be defined as 1 ms, and here, one frame 2-00 may be configured by a total of 10 subframes 2-01. One time slot 2-02 or 2-03 may be defined as 14 OFDM symbols (i.e., the number of symbols per time slot is 14 OFDM symbols). One subframe 2-01 may be configured by one or more time slots 2-02 and 2-03, and the number of time slots 2-02 and 2-03 per one subframe 2-01 may be different according to the configured value μ2-04 or 2-05 for the subcarrier spacing. Figure 2 In the example of FIG. 1 , the case where the subcarrier spacing configuration value is μ=0 (indicated by reference numeral 2-04) and μ=1 (indicated by reference numeral 2-05) is shown. In the case of μ=0 (indicated by reference numeral 2-04), one subframe 2-01 may include one time slot 2-02, and in the case of μ=1 (indicated by reference numeral 2-05), one subframe 2-01 may include two time slots 2-03. That is, the number of time slots per subframe is The number of slots per frame may vary depending on the subcarrier spacing configuration value μ and therefore Can be different. Configure μ according to each subcarrier spacing, and It can be defined in Table 1 below.

[0068]

Table 1

[0069]

[0070] In NR, one component carrier (CC) or serving cell may include up to 250 RBs or more. Therefore, when the UE always receives the entire serving cell bandwidth (such as in the LTE system), the power consumption of the UE may be very large, and to solve this problem, the base station may configure one or more bandwidth parts (BWPs) for the UE to support the UE to change the reception area within the cell. In NR, the base station may configure the "initial BWP" for the terminal via the master information block (MIB), that is, the bandwidth of CORESET#0 (or common search space (CSS)). Thereafter, the base station may configure the initial BWP (first BWP) of the UE via radio resource control (RRC) signaling, and may notify at least one BWP configuration information that may be indicated by downlink control information (DCI) in the future. Thereafter, the base station may notify the BWP ID via DCI to indicate which frequency band the UE is to use. If the UE does not receive DCI in the currently allocated BWP for a specific period of time or longer, the UE returns to the "default bandwidth part" and attempts to receive the DCI.

[0071] 5G bandwidth part

[0072] Figure 3 An example of bandwidth part (BWP) configuration in a wireless communication system according to an embodiment of the present disclosure is shown.

[0073] refer to Figure 3 , Figure 3An example is shown in which UE bandwidth 3-00 is configured by two BWPs (ie, BWP#1 3-05 and BWP#2 3-10). The base station can configure one or more BWPs for the UE, and can configure multiple information as shown in Table 2 below for each bandwidth part.

[0074]

Table 2

[0075]

[0076] The embodiments of the present disclosure are not limited to the above examples, and in addition to the configuration information, various parameters related to the BWP may be configured in the UE. The above multiple pieces of information may be transmitted to the UE by the base station via high-layer signaling (e.g., RRC signaling). At least one of the configured one or more BWPs may be activated. Whether to activate the configured BWP may be semi-statically transmitted from the base station to the UE via RRC signaling, or may be dynamically transmitted via a MAC control element (CE) or DCI.

[0077] According to an embodiment, a UE before a radio resource control (RRC) connection may be configured with an initial BWP from a base station through a master information block (MIB) for initial access. More specifically, the UE may receive configuration information about a search space and a control resource set (CORESET) that may transmit a physical downlink control channel (PDCCH) so as to receive system information required for initial access (which may correspond to remaining system information (RMSI) or system information block 1 (SIB 1)) through the MIB in an initial access operation. Each of the control resource set (CORESET) and the search space configured through the MIB may be regarded as an identification (ID) 0.

[0078] The base station may notify the UE of configuration information such as frequency allocation information, time allocation information, and parameter set of control resource set #0 through the MIB. In addition, the base station may notify the UE of configuration information about the monitoring period and timing of control resource set #0, that is, configuration information about search space #0 through the MIB. The UE may regard the frequency domain configured as control resource set #0 obtained from the MIB as the initial BWP for initial access. Here, the identification (ID) of the initial BWP may be regarded as zero.

[0079] The configuration of the BWP supported by the above-mentioned next-generation mobile communication system (5G or NR system) can be used for various purposes.

[0080] As an example, in the case where the bandwidth supported by the UE is less than the system bandwidth, the bandwidth supported by the UE can be supported by the BWP configuration. For example, in Table 2, the frequency position of the BWP is configured for the UE (configuration information 2), and therefore, the UE can transmit or receive data at a specific frequency position within the system bandwidth.

[0081] According to another example, for the purpose of supporting different parameter sets, the base station may configure multiple BWPs in the UE. For example, in order to support both data transmission / reception to / from a predetermined UE using a subcarrier spacing of 15 kilohertz (kHz) and a subcarrier spacing of 30 kHz, two BWPs may be configured to use a subcarrier spacing of 15 kHz and a subcarrier spacing of 30 kHz, respectively. Different BWPs may be frequency division multiplexed (FDM), and when it is desired to transmit or receive data at a specific subcarrier spacing, a BWP configured with the corresponding subcarrier spacing may be activated.

[0082] According to another example, for the purpose of reducing the power consumption of the UE, the base station may configure a BWP with bandwidths of different sizes in the UE. For example, when the UE supports a very large bandwidth, such as a bandwidth of 100 MHz, and always transmits or receives data through the corresponding bandwidth, very large power consumption may occur. In particular, in the absence of business, it is very inefficient for the UE to monitor unnecessary downlink control channels for a large bandwidth of 100 MHz in terms of power consumption. Therefore, for the purpose of reducing the power consumption of the UE, the base station may configure a bandwidth portion of a relatively small bandwidth for the UE, such as a bandwidth portion of 20 MHz. In the absence of business, the UE may perform monitoring operations in the bandwidth portion of 20 MHz. When data has been generated, the UE may transmit or receive data by using the bandwidth portion of 100 MHz according to the instruction of the base station.

[0083] In the method of configuring the bandwidth part, the UE before the RRC connection can receive the configuration information of the initial bandwidth part through the MIB in the initial access operation. More specifically, the UE can be configured with a control region or control resource set (CORESET) for a downlink control channel from the MIB of the physical broadcast channel (PBCH), which can transmit downlink control information (DCI) for scheduling system information blocks (SIBs). The bandwidth of the control resource set configured by the MIB can be regarded as the initial BWP. The UE can receive the PDSCH through which the SIB is transmitted through the configured initial BWP. In addition to the reception of SIBs, the initial BWP can also be used for other system information (OSI), paging and random access.

[0084] SSB / PBCH

[0085] Hereinafter, a synchronization signal (SS) / PBCH block (SSB) of a next-generation mobile communication system (5G or NR system) will be described.

[0086] The SS / PBCH block may refer to a physical layer channel block including a primary SS (PSS), a secondary SS (SSS), and a PBCH. More specifically, the SS / PBCH block may be defined as follows:

[0087] -PSS: It is a signal used as a reference for downlink time / frequency synchronization and can provide some information of a cell ID.

[0088] -SSS: It is used as a reference signal for downlink time / frequency synchronization and can provide the remaining cell ID information not provided by PSS. In addition, SSS can be used as a reference signal for demodulating PBCH.

[0089] -PBCH: It can provide basic system information required for the transmission or reception of data channels and control channels of UE. Basic system information may include search space related control information indicating radio resource mapping information of control channels, scheduling control information of separate data channels for system information transmission, etc.

[0090] -SS / PBCH block: An SS / PBCH block may include a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks may be transmitted within 5 ms, and each of the transmitted SS / PBCH blocks may be distinguished by an index.

[0091] The UE can detect the PSS and SSS in the initial access operation and can decode the PBCH. The UE can obtain the MIB from the PBCH and can be configured with control resource set #0 through the MIB. Based on the assumption that the selected SS / PBCH block and the demodulation reference signal (DMRS) transmitted in the control resource set #0 are quasi-co-located (QCLed), the UE can monitor the control resource set #0. The UE can receive system information through the downlink control information transmitted from the control resource set #0. The UE can obtain the configuration information related to the random access channel (RACH) required for initial access from the received system information. By considering the selected SS / PBCH index, the UE can send a physical RACH (PRACH) to the base station, and the base station receiving the PRACH can obtain information about the SS / PBCH block index selected by the UE. The base station can know which block the UE has selected in the SS / PBCH block, and can know that the UE has monitored the control resource set #0 corresponding to (or associated with) the selected SS / PBCH block.

[0092] PDCCH: Downlink Control Information (DCI)

[0093] Subsequently, DCI in the next-generation mobile communication system (5G or NR system) is described in detail.

[0094] In the next generation mobile communication system (5G or NR system), scheduling information of uplink data (or physical uplink data channel (PUSCH)) or downlink data (or physical downlink data channel (PDSCH)) can be transmitted from the BS to the UE through DCI. The UE can monitor the fallback DCI format and non-fallback DCI format for PUSCH or PDSCH. The fallback DCI format may include a fixed field predefined between the BS and the UE, and the non-fallback DCI format may include a configurable field.

[0095] DCI can be transmitted through PDCCH via a channel coding and modulation process. A cyclic redundancy check (CRC) can be added to the DCI message payload and can be scrambled by 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 (e.g., UE-specific data transmission, power control command, or random access response). That is, the RNTI is not explicitly transmitted, but is included in the CRC calculation process to be transmitted. If a DCI message transmitted through PDCCH is received, the UE can identify the CRC by the assigned RNTI, and when the CRC is determined to be correct based on the CRC identification result, the UE can identify that the corresponding message is transmitted to the UE.

[0096] For example, the DCI for scheduling PDSCH for system information (SI) can be scrambled by SI-RNTI. The DCI for scheduling PDSCH for random access response (RAR) message can be scrambled by random access (RA)-RNTI. The DCI for scheduling PDSCH for paging message can be scrambled by paging (P)-RNTI. The DCI for notifying the slot format indicator (SFI) can be scrambled by SFI-RNTI. The DCI for notifying transmit power control (TPC) can be scrambled with TPC-RNTI. The DCI for scheduling UE-specific PDSCH or PUSCH can be scrambled by cell RNTI (C-RNTI).

[0097] DCI format 0_0 may be used for fallback DCI scheduling PDSCH, in which case the CRC may be scrambled by the C-RNTI.DCI format 0_0 in which the CRC is scrambled by the C-RNTI may include the following information, for example, as shown in Table 3 below.

[0098]

Table 3

[0099]

[0100]

[0101] DCI format 0_1 ​​may be used for scheduling non-fallback DCI for PUSCH, in which case the CRC may be scrambled with the C-RNTI. DCI format 0_1 ​​in which the CRC is scrambled by the C-RNTI may include the following information, for example, as shown in Table 4 below.

[0102]

Table 4

[0103]

[0104]

[0105] DCI format 1_0 may be used for fallback DCI scheduling PDSCH, in which case the CRC may be scrambled by the C-RNTI.DCI format 1_0 in which the CRC is scrambled by the C-RNTI may include the following information, for example, as shown in Table 5 below.

[0106]

Table 5

[0107]

[0108] Alternatively, DCI format 1_0 may be used as DCI for scheduling PDSCH for RAR message, in which case CRC may be scrambled by RA-RNTI.DCI format 1_0 in which CRC is scrambled by RA-RNTI may include the following information as shown in Table 6 below, for example.

[0109]

Table 6

[0110]

[0111]

[0112] DCI format 1_1 may be used for scheduling non-fallback DCI for PDSCH, in which case the CRC may be scrambled by the C-RNTI.DCI format 1_1 in which the CRC is scrambled by the C-RNTI may include the following information, for example, as shown in Table 7 below.

[0113]

Table 7

[0114]

[0115]

[0116] PDSCH QCL rules related to PDCCH

[0117] Hereinafter, a QCL priority determination operation for a PDCCH will be described in detail.

[0118] In the case where the UE operates with carrier aggregation within a single cell or frequency band and multiple control resource sets within the activated bandwidth portion within a single or multiple cells have the same or different QCL-TypeD characteristics in a specific PDCCH monitoring interval and overlap with each other in time, the UE can select a specific control resource set according to the QCL priority determination operation and monitor the control resource set having the same QCL-TypeD characteristics as the corresponding control resource set. That is, when multiple control resource sets overlap in time, only one QCL-TypeD characteristic can be received. In this case, the criteria for determining the QCL priority can be as follows:

[0119] - Criterion 1. A control resource set connected to the common search space with the lowest index in the cell corresponding to the lowest index among the cells including the common search space

[0120] - Criterion 2. A control resource set connected to a UE-specific search space with a lowest index in a cell corresponding to the lowest index among cells including the UE-specific search space

[0121] As described above, when each of the above criteria is not met, the next criteria is applied. For example, when the control resource sets overlap in time in a specific PDCCH monitoring duration, if all control resource sets are not connected to a common search space but to a UE-specific search space, that is, if criterion 1 is not met, the UE may omit the application of criterion 1 and apply criterion 2.

[0122] When selecting a control resource set based on the above criteria, the UE may additionally consider the following two matters for the QCL information configured to the control resource set configuration. First, if control resource set 1 has CSI-RS1 as a reference signal with a QCL-TypeD relationship, and the reference signal with which this CSI-RS1 has a QCL-TypeD relationship is SSB 1, and another control resource set 2 has a reference signal with a QCL-TypeD relationship is SSB 1, then the UE may consider that the two control resource sets 1 and 2 have different QCL-TypeD characteristics. Second, if control resource set 1 has CSI-RS1 configured in cell 1 as a reference signal with a QCL-TypeD relationship, and the reference signal with which CSI-RS1 has a QCL-TypeD relationship is SSB 1, and control resource set 2 has CSI-RS2 configured in cell 2 as a reference signal with a QCL-TypeD relationship, and the reference signal with which CSI-RS2 has a QCL-TypeD relationship is SSB 1, then the UE may consider that the two control resource sets have the same QCL-TypeD characteristics.

[0123] Figure 4The structure of the downlink control channel in the wireless communication system according to the embodiment of the present disclosure is shown. That is, Figure 4 A diagram illustrating an example of a basic unit of time and frequency resources for configuring a downlink control channel that may be used in 4G according to an embodiment of the present disclosure.

[0124] refer to Figure 4 , the basic unit of time and frequency resources for configuring the control channel may be defined as a resource element group (REG) 4-03. REG 4-03 may be defined by 1 OFDM symbol 4-01 on the time axis and by one physical resource block (PRB) 4-02 (ie, 12 subcarriers) on the frequency axis. The base station may cascade REG 4-03 to configure a downlink control channel allocation unit.

[0125] refer to Figure 4 , when the basic unit allocated to the downlink control channel in 5G is a control channel element (CCE) 4-04, 1 CCE 4-04 may include a plurality of REGs 4-03. For example, when REG 4-03 may include 12 REs and 1 CCE 4-04 includes 6 REGs 4-03 (in Figure 4 ), 1 CCE 4-04 may include 72 REs. When a downlink control resource set is configured, the corresponding area may include multiple CCE 4-04s. In the control resource set, a specific downlink control channel may be transmitted after being mapped to one or more CCE 4-04s according to an aggregation level (AL). CCEs 4-04 in the control resource set are distinguished by numbers. Here, the numbers of CCEs 4-04 may be assigned according to a logical mapping scheme.

[0126] Figure 4 The basic unit of the downlink control channel shown (ie, REG 4-03) may include both REs to which DCI is mapped and regions 4-04 to which DMRS, which is a reference signal for decoding DCI, is mapped. Figure 4 As shown, three DMRS 4-05 can be transmitted in one REG 4-03. Depending on the aggregation level (AL), the number of CCEs required for transmission of the PDCCH can be 1, 2, 4, 8 or 16. Different numbers of CCEs can be used to implement link adaptation of the downlink control channel. For example, in the case of AL=L, one downlink control channel can be transmitted via L CCEs.

[0127] The UE needs to detect the signal in a state where the UE does not know information about the downlink control channel, and a search space indicating a set of CCEs for blind decoding can be defined. The search space is a set of downlink control channel candidates including CCEs that the UE must attempt to decode with a given AL. Since there are various ALs that constitute a bundle of 1, 2, 4, 8 or 16 CCEs, the UE can have multiple search spaces. A search space set can be defined as a set of search spaces under all configured ALs.

[0128] The search space may be classified into a common search space and a UE-specific search space. According to an embodiment of the present disclosure, a predetermined group of UEs or all UEs may check the common search space of the PDCCH in order to receive cell common control information such as system information or dynamic scheduling of a paging message.

[0129] For example, the UE can receive PDSCH scheduling allocation information for SIB transmission by checking the common search space of PDCCH, and the SIB includes the operator information of the cell, etc. In the case of the common search space, since a predetermined group of UEs or all UEs need to receive PDCCH, the common search space can be defined as a set of previously promised CCEs. On the other hand, the UE can receive scheduling allocation information about UE-specific PDSCH or PUSCH by checking the UE-specific search space of PDCCH. The UE-specific search space can be UE-specifically defined according to the UE identity and various system parameters.

[0130] In 5G, the parameters of the search space for PDCCH can be configured by the base station for the UE via high-level signaling (e.g., SIB, MIB, and RRC signaling). For example, the base station can configure the number of PDCCH candidates at each aggregation level L, the monitoring periodicity of the search space, the monitoring timing of the symbol unit in the time slot of the search space, the search space type (common search space or UE-specific search space), the combination of RNTI and DCI format to be monitored in the search space, the control resource set index for monitoring the search space, etc. For example, the above configuration information may include the following multiple pieces of information in Table 8 below.

[0131]

Table 8

[0132]

[0133]

[0134]

[0135] The base station may configure one or more search space sets for the UE based on the configuration information. According to an embodiment of the present disclosure, the base station may configure search space set 1 and search space set 2 in the UE. The base station may configure search space set 1 and search space set 2 in the UE, and the DCI format A scrambled by X-RNTI in search space set 1 may be configured to be monitored in the common search space, and the DCI format B scrambled by Y-RNTI in search space set 2 may be configured to be monitored in the UE-specific search space.

[0136] According to the configuration information, one or more search space sets may exist in a common search space or a UE-specific search space. For example, search space set #1 and search space set #2 may be configured as common search spaces, and search space set #3 and search space set #4 may be configured as UE-specific search spaces.

[0137] The common search space may be classified into a specific type of search space set according to the purpose. Depending on the determined type of search space set, the RNTI to be monitored may be different. For example, the common search space type, purpose, and RNTI to be monitored may be classified as shown in Table 9 below.

[0138]

Table 9

[0139]

[0140]

[0141] Meanwhile, in the common search space, the following combinations of DCI formats and RNTIs may be monitored. However, the present disclosure is not limited thereto.

[0142] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, Configured Scheduling (CS)-RNTI, Semi-Persistent (SP)-CSI-RNTI, RA-RNTI, Temporary Cell (TC)-RNTI, P-RNTI, SI-RNTI

[0143] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0144] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0145] -DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0146] -DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0147] In the UE-specific search space, the following combinations of DCI formats and RNTIs may be monitored. However, the present disclosure is not limited thereto.

[0148] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0149] -DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0150] The specified RNTI may follow the definition and usage described below.

[0151] Cell RNTI (C-RNTI): used for UE-specific PDSCH scheduling

[0152] Temporary Cell RNTI (TC-RNTI): used for UE-specific PDSCH scheduling

[0153] Configured Scheduling RNTI (CS-RNTI): used for semi-statically configured UE-specific PDSCH scheduling

[0154] Random Access RNTI (RA-RNTI): used for PDSCH scheduling in random access operation Paging RNTI (P-RNTI): used for scheduling of PDSCH through which paging is transmitted

[0155] System Information RNTI (SI-RNTI): used for transmitting PDSCH scheduling interruption RNTI (INT-RNTI): used to notify whether to truncate PDSCH

[0156] PUSCH Transmit Power Control RNTI (TPC-PUSCH-RNTI): used to indicate the power control command of PUSCH

[0157] PUCCH Transmit Power Control RNTI (TPC-PUCCH-RNTI): used to indicate the power control command of PUCCH

[0158] SRS Transmit Power Control RNTI (TPC-SRS-RNTI): used to indicate the power control command of SRS

[0159] In an embodiment, the above-mentioned DCI format may be defined as shown in Table 10 below.

[0160]

Table 10

[0161]

[0162] According to an embodiment of the present disclosure, in 5G, multiple search space sets may be configured with different parameters (e.g., parameters in [Table 8]). Therefore, the set of search space sets monitored by the UE may change at each time point. For example, in the case where 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 UE may monitor both search space set #1 and search space set #2 in a specific time slot, and may monitor one of search space set #1 and search space set #2 in a specific time slot.

[0163] When multiple search space sets are configured for a UE, the following conditions may be considered in order to determine the search space set to be monitored by the UE.

[0164] Condition 1: Limit the maximum number of PDCCH candidates

[0165] The number of PDCCH candidates that can be monitored in each time slot cannot exceed M μ . M μ can be defined as being configured as 15·2 μ The maximum number of PDCCH candidates per time slot in a cell with a subcarrier spacing of kHz and can be defined as shown in the following Table 11.

[0166]

Table 11

[0167]

[0168]

[0169] Condition 2: Limiting the maximum number of CCEs

[0170] The number of CCEs that configure the entire search space in each time slot (here, the entire search space may refer to the entire CCE set corresponding to the joint area of ​​multiple search space sets) shall not exceed C μ . C μ can be defined as being configured as 15·2 μ The maximum number of CCEs per time slot in a cell with a subcarrier spacing of kHz and can be defined as shown in Table 12 below.

[0171]

Table 12

[0172] μ Maximum number of non-overlapping CCEs per timeslot and per serving cell 0 56 1 56 2 48 3 32

[0173] For the convenience of description, a case where both condition 1 and condition 2 are satisfied at a certain point in time is defined as “condition A.” Therefore, not satisfying condition A may mean that at least one of the above conditions 1 and 2 is not satisfied.

[0174] According to the configuration of the search space set of the base station, there may be a situation where condition A is not satisfied at a specific time point. If condition A is not satisfied at a specific time point, the UE may select and monitor only some search space sets configured to satisfy condition A at the corresponding time point, and the base station may send the PDCCH to the selected search space set.

[0175] According to an embodiment of the present disclosure, a method for selecting some search spaces from the entire configured search space set may follow the following method.

[0176] If the PDCCH condition A is not met at a specific time point (time slot),

[0177] The UE (or base station) may preferentially select a search space set in which the search space type is configured as a common search space rather than a search space set in which the search space type is configured as a UE-specific search space from the search space sets existing at the corresponding time point.

[0178] If all search space sets configured as common search spaces are selected (i.e., if condition A is satisfied even after all search spaces configured as common search spaces are selected), the UE (or base station) may select a search space set configured as a UE-specific search space. Here, if there are multiple search space sets configured as UE-specific search spaces, a search space set with a lower search space set index may have a higher priority. Considering the priority, the UE or base station may select a UE-specific search space set within the range that satisfies condition A.

[0179] The following describes a method for allocating time and frequency resources for data transmission in NR.

[0180] In NR, in addition to the frequency domain resource candidate allocation indicated by BWP, the following detailed frequency domain resource allocation (FD-RA) method can also be provided.

[0181] Figure 5 An example of frequency domain resource allocation of a physical downlink shared channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure is shown.

[0182] Figure 5 Three frequency domain resource allocation methods in NR that can be configured by higher layers are shown: Type 0 (5-00), Type 1 (5-05), and dynamic switching (5-10).

[0183] refer to Figure 5, in the case where the UE is configured to use only resource type 0 (indicated by reference numeral 5-00) via high-level signaling, some downlink control information (DCI) for allocating PDSCH to the corresponding UE includes a bitmap configured by a non-deterministic random bit generator (NRBG) bit. Its conditions will be described again later. Here, NRBG represents the number of resource block groups (RBGs) determined according to the BWP size allocated by the BWP indicator and the high-level parameter rbg-Size as shown in Table 13 below, and data is sent to the RBG indicated by the bitmap as "1".

[0184]

Table 13

[0185] Bandwidth portion size Configuration 1 Configuration 2 1-36 2 4 37-72 4 8 73-144 8 16 145-275 16 16

[0186] If the UE is configured via higher layer signaling to use only resource type 1 (indicated by reference numeral 5-05), some DCI for allocating PDSCH to the UE includes The base station may configure the frequency domain resource allocation information of the starting VRB 5-20 and the length 5-25 of the frequency domain resources continuously allocated therefrom.

[0187] In the case where the UE is configured to use both resource type 0 and resource type 1 (indicated by reference numeral 5-10) via high-layer signaling, some DCIs for allocating PDSCH to the UE include frequency domain resource allocation information configured by a payload 5-15 for configuring resource type 0 and a larger value bit 5-35 between payloads 5-20 and 5-25 for configuring resource type 1, and the conditions for the above configuration will be described later. Here, one bit (indicated by reference numeral 5-30) may be added to the most significant bit (MSB) of the frequency domain resource allocation information in the DCI, and when the corresponding bit has a value of 0, it may indicate that resource type 0 is used, and when the corresponding bit has a value of 1, it may indicate that resource type 1 is used.

[0188] Hereinafter, a method of allocating time domain resources to a data channel in a next-generation mobile communication system (5G or NR system) will be described.

[0189] The base station may configure a table of 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)) for the UE via high-layer signaling (e.g., RRC signaling). With respect to PDSCH, a table including maxNrofDL-Allocations=16 entries may be configured, and with respect to PUSCH, a table including maxNrofUL-Allocations=16 entries may be configured. In an embodiment, the time domain resource allocation information may include PDCCH-to-PDSCH slot timing (corresponding to the time interval in time slots between the time point at which the PDCCH is received and the time point at which the PDSCH scheduled by the received PDCCH is transmitted, and is represented as K0), PDCCH-to-PUSCH slot timing (corresponding to the time interval in time slots between the time point at which the PDCCH is received and the time point at which the PUSCH scheduled by the received PDCCH is transmitted, and is represented as K2), information about the position and length of the starting symbol of the PDSCH or PUSCH scheduled within the time slot, the mapping type of the PDSCH or PUSCH, etc. For example, the base station may notify the UE of information such as Table 14 or Table 15 below.

[0190]

Table 14

[0191]

[0192]

Table 15

[0193]

[0194] The base station may notify the UE of one of the entries in the above table about the time domain resource allocation information via L1 signaling (e.g., DCI) (e.g., may be indicated by the "time domain resource allocation" field in the DCI). The UE may acquire the time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

[0195] Figure 6 An example of time domain resource allocation of a PDSCH in a wireless communication system according to an embodiment of the present disclosure is shown.

[0196] refer to Figure 6 , the base station can use the subcarrier spacing (SCS) (μ PDSCH , μ PDCCH ), scheduling offset (K 0 ) value and the starting position 6-00 and length 6-05 of an OFDM symbol in a time slot 6-10 dynamically indicated by the DCI to indicate the time domain position of the PDSCH resource.

[0197] Figure 7 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 is shown.

[0198] refer to Figure 7 , if the data channel and control channel have the same subcarrier spacing (7-00, μ PDSCH =μ PDCCH ), since the number of data time slots and the number of control time slots are the same, the base station and the UE can recognize that the predetermined time slot offset K 0 On the other hand, when the subcarrier spacing of the data channel is different from that of the control channel (7-05, μ PDSCH ≠μ PDCCH ), the number of data time slots and the number of control time slots are different, and therefore the base station and the UE can recognize that the subcarrier spacing based on the PDCCH is offset according to the predetermined time slot K 0 A scheduling offset occurs.

[0199] QCL, TCI status

[0200] In a wireless communication system, one or more different antenna ports (or one or more channels, signals and combinations thereof, but for convenience of description, generally referred to as different antenna ports) may be associated via the QCL configuration shown in Table 16 below. The TCI state is used to notify the QCL relationship between a PDCCH (or PDCCH DMRS) and another RS ​​or channel, and the reference antenna port A (e.g., reference RS#A) and another destination antenna port B (e.g., target RS#B) of the quasi-co-location (QCL) means that the UE is allowed to apply some or all of the large-scale channel parameters estimated in antenna port A to the channel measurement results from antenna port B. QCL is required to associate different parameters depending on the conditions: such as time tracking affected by average delay and delay spread, frequency tracking affected by Doppler shift and Doppler spread, radio resource management (RRM) affected by average gain, and beam management (BM) affected by spatial parameters. Therefore, NR supports four types of QCL relationships shown in Table 16 below.

[0201]

Table 16

[0202]

[0203] The spatial Rx parameters may refer to some or all of the angle of arrival (AoA), the power angular spectrum (PAS) of AoA, the angle of departure (AoD), the PAS of AoD, the transmit / receive channel correlation, the transmit / receive beamforming, and the spatial channel correlation.

[0204] The QCL relationship can be configured in the UE through the RRC parameters TCI-State and QCL-Info, as shown in Table 17 below. Referring to Table 17 below, the BS can configure one or more TCI states in the UE and notify the UE of up to two QCL relationships (QCL-Type 1 and QCL-Type 2) for the RS (ie, target RS) of the ID involved in the TCI state. Each piece of QCL information (QCL-Info) included in the TCI state includes a serving cell index and a BWP index of a reference RS indicated by the corresponding QCL information, a type and ID of the reference RS, and a QCL type as shown in Table 16 above.

[0205]

Table 17

[0206]

[0207]

[0208] Method and apparatus for transmitting HARQ-ACK feedback

[0209] When a decoding failure occurs in the initial transmission, the NR system adopts a hybrid automatic repeat request (HARQ) method for retransmitting the corresponding data in the physical layer. In the HARQ method, when the receiver fails to accurately decode the data, the receiver transmits information indicating the decoding failure (negative acknowledgment (NACK)) to the transmitter so that the transmitter can retransmit the corresponding data in the physical layer. The receiver improves the data reception performance by combining the data retransmitted by the transmitter with the data that failed to be decoded previously. In addition, when the receiver correctly decodes the data, the receiver can transmit information indicating the decoding success (acknowledgement (ACK)) to the transmitter so that the transmitter can transmit new data.

[0210] In the following disclosure, a method and apparatus for transmitting HARQ-ACK feedback for downlink data transmission will be described. Specifically, a method for configuring HARQ-ACK feedback bits when a UE intends to transmit multiple HARQ-ACKs within one slot in an uplink will be described.

[0211] In a wireless communication system, especially a new radio (NR) system, a base station can configure a component carrier (CC) or multiple CCs for downlink transmission to a terminal. In addition, downlink transmission and uplink transmission time slots and symbols can be configured in each CC. At the same time, when scheduling a physical downlink shared channel (PDSCH) as downlink data, at least one of the time slot timing information mapped to the PDSCH in a specific bit field in the downlink control information (DCI), the starting symbol position mapped to the PDSCH in the corresponding time slot, and the information about the number of symbols mapped to the PDSCH can be transmitted. For example, when DCI is delivered in time slot n and PDSCH is scheduled, when K0, which is the timing information of the time slot through which the PDSCH is delivered, indicates 0, the starting symbol position is 0, and the symbol length is 7, the corresponding PDSCH is mapped to 7 symbols from symbol 0 of time slot n and is transmitted. At the same time, the PDSCH as a downlink data signal is transmitted, and HARQ-ACK feedback is transmitted from the UE to the base station after the K1 time slot. K1 information, which is timing information for transmitting HARQ-ACK, is delivered from DCI, and a set of candidate possible K1 values ​​is delivered in higher layer signaling, and one of them may be determined in DCI.

[0212] When the UE receives a semi-static HARQ-ACK codebook configuration, the UE may determine a table including K0, starting symbol information, symbol number or length information, and feedback bits (or HARQ-ACK codebook size) to be transmitted based on a K1 candidate value, where the K1 candidate value is HARQ-ACK feedback timing information for the PDSCH. The table including the time slot information, starting symbol information, symbol number or length information to which the PDSCH is mapped may follow a default value or may be configured by the base station to the terminal.

[0213] When the UE receives a dynamic HARQ-ACK codebook, the UE can determine the HARQ-ACK feedback bit (or HARQ-ACK codebook size) to be transmitted in the time slot for transmitting the HARQ-ACK information by the DAI (downlink assignment indicator) information included in the DCI, and the time slot for transmitting the HARQ-ACK information is based on the time slot information to which the PDSCH is mapped and the HARQ-ACK feedback timing information K0 for the PDSCH K1 value.

[0214] Figure 8 2 is a view showing a method for configuring a semi-static HARQ-ACK codebook in an NR system according to an embodiment of the present disclosure.

[0215] In the case where the number of HARQ-ACK PUCCHs that can be transmitted by the UE is limited to one in one time slot, when the UE receives a higher layer signal for configuring a semi-static HARQ-ACK codebook, the UE may report HARQ-ACK information for PDSCH reception or SPS (semi-persistent scheduling) PDSCH release in the HARQ-ACK codebook in the time slot indicated by the value of the PDSCH-to-HARQ_feedback timing indicator field included in DCI format 1_0 or DCI format 1_1. The UE may report the HARQ-ACK information bit value in the HARQ-ACK codebook as NACK in the time slot not indicated by the value of the PDSCH-to-HARQ_feedback timing indicator in DCI format 1_0 or DCI format 1_1. If the UE reports HARQ-ACK information only for one SPS PDSCH release or one PDSCH reception in the MA,c case for candidate PDSCH reception, and the report is scheduled by DCI format 1_0 including information indicating that the counter DAI is 1 in Pcell, the UE can determine a HARQ-ACK codebook for the corresponding SPS PDSCH release or the corresponding PDSCH reception.

[0216] Otherwise, the HARQ-ACK codebook determination method according to the following method may be followed.

[0217] If MA,c is a set of PDSCH reception candidate cases in serving cell c, MA,c may be obtained by the following [pseudo code 1] steps.

[0218] [Begin pseudocode 1]

[0219] - Step 1: Initialize j to 0 and initialize MA,c to an empty set. Initialize k, which is the HARQ-ACK transmission timing index, to 0.

[0220] - Step 2: R is configured as a set of rows in a table including time slot information, starting symbol information, symbol number or length information to which PDSCH is mapped. If the mapped symbol supporting PDSCH indicated by each R value is configured as a UL symbol according to the DL and UL configuration configured at the higher layer, the corresponding row is deleted from R.

[0221] - Step 3-1: The UE may receive one PDSCH for unicast in one slot, and when R is not an empty set, add one to the set MA,c.

[0222] - Step 3-2: If the UE can receive more than one PDSCH for unicast in one slot, count the number of PDSCHs that can be allocated to different symbols in the calculated R, and add the corresponding number to MA,c.

[0223] - Step 4: Increment k by 1 to start from step 2 again.

[0224] [End pseudocode 1]

[0225] refer to Figure 8 , with respect to the aforementioned pseudo code 1, in order to perform HARQ-ACK PUCCH transmission in time slot #k 8-08, the UE may consider all time slot candidates that can indicate time slot #k 8-08 that are capable of PDSCH-to-HARQ-ACK timing. Figure 8 In the example, it is assumed that HARQ-ACK transmission can be performed in time slot #k 8-08 by combining PDSCH-to-HARQ-ACK timing (this is only possible for PDSCHs scheduled in time slot #n 8-02, time slot #n+1 8-04, and time slot #n+2 8-06). In addition, the maximum number of schedulable PDSCHs per time slot can be derived taking into account the time domain resource configuration information of the PDSCHs that can be scheduled in time slots 8-02, 8-04, and 8-06, respectively, and the information indicating whether the symbol in the time slot is downlink or uplink. For example, if a maximum scheduling of 2 PDSCHs is possible in time slot 8-02, a maximum scheduling of 3 PDSCHs is possible in time slot 8-04, and a maximum scheduling of 2 PDSCHs is possible in time slot 8-06, respectively, the maximum number of PDSCHs included in the HARQ-ACK codebook transmitted in time slot 8-08 is 7 in total. This is called the cardinality of the HARQ-ACK codebook.

[0226] Fig. 9 2 is a view showing a method for configuring a dynamic HARQ-ACK codebook in an NR system according to an embodiment of the present disclosure.

[0227] The UE can transmit HARQ-ACK information transmitted in one PUCCH in the corresponding time slot n based on the PDSCH-to-HARQ_feedback timing value transmitted by the PUCCH for HARQ-ACK information for PDSCH reception or SPS PDSCH release and K0 which is the transmission time slot position information of the PDSCH scheduled in DCI format 1_0 or 1_1.

[0228] Specifically, for the above-mentioned HARQ-ACK information transmission, the UE may determine the HARQ-ACK codebook of the PUCCH transmitted in the time slot indicated by the PDSCH-to-HARQ_FeedbackTiming and K0 based on the DAI included in the DCI indicating the PDSCH or SPS PDSCH release.

[0229] DAI consists of a counter DAI (cCounter DAI) and a total DAI (tTotal DAI). Counter DAI is information indicating the position of the HARQ-ACK information corresponding to the PDSCH scheduled in DCI format 1_0 or DCI format 1_1 in the HARQ-ACK codebook. Specifically, the value of the counter DAI in DCI format 1_0 or 1_1 notifies the accumulated value of PDSCH reception or SPS PDSCH release scheduled by DCI format 1_0 or DCI format 1_1 in a specific cell c. The aforementioned accumulated value is configured based on the PDCCH monitoring timing and the serving cell in which the scheduled DCI exists.

[0230] The total DAI is a value indicating the HARQ-ACK codebook size. Specifically, the value of the total DAI means the total number of previously scheduled PDSCH or SPS PDSCH releases, including the time point when the DCI is scheduled (PDCCH monitoring opportunity). In addition, the total DAI is a parameter used when the HARQ-ACK information on the serving cell c in the case of carrier aggregation (CA) also includes HARQ-ACK information for the PDSCH scheduled in another cell including the serving cell c. In other words, there is no total DAI parameter in a system operating with one cell.

[0231] Fig. 9 is a view showing an example of an operation of a UE related to DAI when a dynamic HARQ-ACK codebook is used. Fig. 9 The figure shows the changes in the values ​​of the counter DAI (C-DAI) and the total DAI (T-DAI) indicated by the DCI found for each PDCCH monitoring opportunity set for each carrier when the HARQ-ACK codebook selected based on the DAI on the PUCCH (920) is transmitted in the nth time slot of carrier 0 (902) when the UE is configured with two carriers (c). First, in the DCI searched at m=0 (906), the C-DAI and T-DAI indicate a value of 1 (912). In the DCI searched at m=1 (908), the C-DAI and T-DAI each indicate a value of 2 (914). In the DCI found in carrier 0 (c=0, 902) with m=2 (910), the C-DAI indicates a value of 3 (916). In the DCI found in carrier 1 (c=1, 904) with m=2 (910), the C-DAI indicates a value of 4 (918). In this case, when carriers 0 and 1 are scheduled on the same monitoring occasion, both T-DAIs are indicated as 4.

[0232] refer to Figure 8 and Fig. 9, the HARQ-ACK codebook determination can be operated based on the assumption that only one PUCCH containing HARQ-ACK information is transmitted in one time slot. As an example of a method for determining one PUCCH transmission resource in one time slot, when PDSCHs scheduled in different DCIs are multiplexed in one HARQ-ACK codebook in the same time slot and transmitted, the PUCCH resources selected for HARQ-ACK transmission can be determined as the PUCCH resources indicated by the PUCCH resource field indicated in the DCI that last scheduled the PDSCH. That is, the PUCCH resources indicated by the PUCCH resource field indicated in the DCI scheduled before the DCI are ignored.

[0233] Method and apparatus for canceling uplink transmission

[0234] When eMBB services and URLLC services coexist in the NR system, a method for canceling eMBB uplink data transmission or SRS transmission has been added to improve the security and speed of URLLC. If the UE is configured for uplink cancellation (UplinkCancellation) by high-level signaling, discovery information and CCE aggregation level information capable of monitoring DCI format 2_4 can be provided to the UE. DCI format 2_4 is a UE common DCI scrambled with ci-RNTI (cancellation indication-radio network temporary identifier) ​​in one or more cells. In addition, high-level signaling such as the location of necessary information in the UE common DCI and the time-frequency domain in which the uplink transmission is canceled can be provided to the UE. If the indicated uplink transmission cancellation area and PUSCH or SRS overlap by at least one symbol, the UE may not transmit PUSCH or SRS.

[0235] Method and apparatus for postponing HARQ-ACK for SPS D SCH

[0236] In the URLLC of the NR system, when the HARQ-ACK for the SPS PDSCH overlaps with the transmission of the downlink symbol or SSB and is canceled, a method is added to postpone and transmit the HARQ-ACK information for this purpose. When spsHARQdeferral is configured by high-level signaling and the following conditions are met, the UE can determine the new PUCCH resource for the HARQ-ACK information received by the SPS PDSCH included in the existing PUCCH resources:

[0237] - When the existing PUCCH resources are configured to the SPS-PUCCH-AN-List, or when the SPS-PUCCH-AN-List is not configured but provided as n1PUCCH-AN,

[0238] - when overlapping with a PUSCH or PUCCH with a higher priority but not cancelled, and / or

[0239] -When overlapping with downlink TDD mode, SSB or CORESET#0.

[0240] In this case, after determining to multiplex the PUCCH and the PUSCH in the nearest uplink time slot, the UE may transmit the HARQ-ACK information included in the existing PUCCH on a new PUCCH or a PUSCH.

[0241] Method and apparatus for retransmitting HARQ-ACK codebook

[0242] In the URLLC of the NR system, when a PUCCH or PUSCH including HARQ-ACK information is discarded by an uplink signal with a higher priority, a method is added to retransmit only the discarded HARQ-ACK information instead of starting from PDSCH retransmission.

[0243] Fig.10 2 is a view showing a method for configuring HARQ-ACK codebook retransmission in an NR system according to an embodiment of the present disclosure.

[0244] refer to Fig.10 , assuming that the transmission of a PUCCH (10-01) including a type-1 codebook or a type-2 codebook in time slot m (10-04) is discarded by an uplink signal with a higher priority. In order to retransmit the HARQ-ACK information included in the discarded PUCCH (10-01), a DCI format (10-02) may be indicated by the base station to the UE, which scrambles the CRC with a C-RNTI or MCS-RNTI and does not schedule the PDSCH. When the last time slot of the PDCCH including the DCI format is time slot n (10-05), the DCI format may indicate that a UE PUCCH transmission (10-03) including the HARQ-ACK information included in the previous PUCCH (10-01) is performed in time slot n+k (10-06). In this case, time slot n+k is located after time slot m.

[0245] If the value of pdsch-HARQ-ACK-retx or pdsch-HARQ-ACK-retxDCI-1-2, which is a field included in DCI format 1_1 or 1_2, is '1', the UE may determine m of slot m as follows:

[0246] -m=nl,

[0247] -l has values ​​between -7 and 24,

[0248] -l can be determined by a one-to-one mapping in ascending order in the MCS field of DCI format 1_1 or DCI format 1_2.

[0249] The UE may also multiplex and transmit a HARQ-ACK codebook different from an existing HARQ-ACK codebook on the PUCCH transmitted in slot n+k. The multiplexing operation may follow the existing HARQ-ACK codebook multiplexing operation.

[0250] TDD UL-DL Mode and SFI

[0251] In a 5G communication system, the downlink signal transmission period and the uplink signal transmission period can be changed dynamically. To this end, the base station can indicate to the UE through a slot format indicator (SFI) whether each of the OFDM symbols that make up a time slot is a downlink symbol, an uplink symbol, or a flexible symbol. Here, a flexible symbol may mean a symbol that is neither a downlink symbol nor an uplink symbol, or a symbol that can be changed to a downlink or uplink symbol through UE-specific control information or scheduling information. In this case, the flexible symbol may include gap protection necessary in the process of switching from downlink to uplink.

[0252] The UE receiving the slot format indicator may receive a downlink signal from the base station in a symbol indicated by the downlink symbol, and transmit an uplink signal to the base station in a symbol indicated by the uplink symbol. For symbols indicated as flexible symbols, the UE may at least perform a PDCCH monitoring operation, receive a downlink signal from the base station in a flexible symbol (e.g., when DCI format 1_0 or 1_1 is received) through another indicator such as DCI, or transmit an uplink signal to the base station in a flexible symbol (e.g., when DCI format 0_0 or 0_1 is received).

[0253] Fig.11 An example of an uplink-downlink configuration (UL / DL configuration) in a 5G system is shown. Fig.11 Three steps of uplink-downlink configuration of symbols / time slots according to an embodiment of the present disclosure are shown.

[0254] refer to Fig.11 In the first step, cell-specific configuration information 1110 for configuring uplink-downlink in a semi-static manner may be configured.

[0255] For example, the uplink-downlink of the symbol / time slot may be configured through system information such as SIB. Specifically, the cell-specific uplink-downlink configuration information 1110 in the system information may include uplink-downlink mode information and information indicating the reference subcarrier spacing. The uplink-downlink mode information may indicate the transmission periodicity 1103 of each mode, the number 1111 of consecutive complete DL time slots 1101 at the beginning of each DL-UL mode, the number of consecutive downlink symbols 1102 starting from the next time slot (the number of consecutive DL symbols at the beginning of the time slot after the last complete DL time slot) 1112, the number of consecutive complete UL time slots at the end of each DL-UL mode 1113, and the number of consecutive UL symbols at the end of the time slot before the first complete UL time slot 1114. In this case, the UE may determine the time slot / symbol that is not indicated as uplink or downlink as a flexible time slot / symbol.

[0256] As a second step, UE-specific configuration information 1120 transmitted through UE-specific high-layer signaling (i.e., RRC signaling) indicates symbols configured for downlink or uplink in flexible time slots or time slots 1121 and 1122 including flexible symbols. For example, the UE-specific uplink-downlink configuration information 1120 may include a time slot index indicating the time slots 1121, 1122 containing flexible symbols, the number of consecutive DL symbols 1123, 1125 at the beginning of the time slot, the number of consecutive UL symbols 1124, 1126 at the end of the time slot, or may include information indicating the entire downlink or information indicating the entire uplink for each time slot. In this case, the symbol / time slot configured for uplink or downlink through the cell-specific configuration information 1110 of the first step may be changed to downlink or uplink through the UE-specific high-layer signaling 1120.

[0257] As a third step, in order to dynamically change the downlink signal transmission period and the uplink signal transmission period, the downlink control information of the downlink control channel includes a time slot format indicator 1130, which indicates whether each symbol is a downlink symbol (or downlink resource 1104), an uplink symbol (or uplink resource 1106) or a flexible symbol (or flexible resource 1105) in each of a plurality of time slots starting from the time slot in which the UE detects the downlink control information. In this case, for symbols / time slots configured as uplink or downlink in the first and second steps, the time slot format indicator cannot indicate whether they are downlink or uplink. In the first and second steps, the time slot format of each time slot 1131 or 1132 including at least one symbol not configured for uplink or downlink can be indicated by the corresponding downlink control information.

[0258] The slot format indicator may indicate an uplink-downlink configuration of 14 symbols in one slot, as shown in Table 18 below. The slot format indicator may be transmitted to multiple terminals simultaneously via a UE group (or cell) common control channel. In other words, the downlink control information including the slot format indicator may be transmitted via a CRC-scrambled PDCCH having an identifier (e.g., SFI-RNTI) different from the UE-specific C-RNTI (cell-RNTI). The downlink control information may include a slot format indicator for one or more slots (i.e., N slots). Here, the value of N may be an integer greater than 0, or a value configured by the UE in a set of predefined possible values ​​(such as 1, 2, 5, 10, 20, etc.) via high-level signaling from a base station. The size of the slot format indicator may be configured by the base station to the UE via high-level signaling. Table 18 is a table describing the contents of the SFI.

[0259]

Table 18

[0260]

[0261] In Table 18, D means downlink symbol, U means uplink symbol, and F means flexible symbol. According to Table 18, the total number of slot formats that can be supported by one slot is 256. The maximum size of information bits that can be used for slot format indication in the NR system is 128 bits, and the base station can configure the UE to the UE through high-layer signaling, for example, "dci-PayloadSize".

[0262] Based on the above description, embodiments of the present disclosure will be described in detail.

[0263] Coverage is a very important parameter in wireless communication systems. Currently, 5G is commercialized and millimeter waves are also included in the commercialization, but due to limited coverage, there are not many practical uses. At the same time, many operators are looking for economical ways to provide stable coverage. The situation of installing multiple base stations can be considered, but due to the high cost, more economical methods have been sought.

[0264] For this reason, the first technology considered is the integrated access and backhaul (IAB) studied in Rel-16 and Rel-17. IAB is a relay that does not require a backhaul network connected by a line, and acts as a relay between a base station and a terminal. IAB has similar performance to a base station, but has the disadvantage of increased cost. Second, the existing RF repeater can be considered. The RF repeater is the most basic unit repeater that amplifies and transmits incoming signals. The advantage of the RF repeater is that it is cheap, because the RF repeater only performs the operation of amplification and transmission, but cannot actively respond to various situations. For example, beamforming gain cannot be obtained because the RF repeater generally does not use a directional antenna but an omnidirectional antenna (omnidirectional antenna). In addition, even when no UE is connected to the RF repeater, it may be a source of interference because the noise is amplified and transmitted. Since IAB and RF repeaters have deviations in either direction between performance and cost, their advantages and disadvantages are obvious. In order to effectively increase the coverage, not only performance but also cost should be considered, so there is a need for new UEs or amplifiers.

[0265] In 3GPP Rel-18, research is underway on a network controlled repeater (NCR) that maintains the simple amplification and transmission operations of an RF repeater and implements beamforming technology with an adaptive antenna. In order for the NCR to be able to send signals to the UE using an adaptive antenna within the cell of the base station, the NCR should be able to receive control signals from the base station. Therefore, the NCR may be composed of a network controlled repeater-mobile terminal (NCR-MT) and a network controlled repeater-forwarding unit (NCR-FU), similar to the IAB. From the perspective of the base station, the NCR-MT may perform communications like a normal UE. On the other hand, the NCR-FU may be composed only of a basic RF or physical layer, and may perform transmission and reception operations using an adaptive antenna under the control of the base station. The NCR may perform dynamic TDD configuration, on / off or power control for interference control, and transmission and reception operations using an adaptive antenna.

[0266] NCR can basically amplify the signal transmitted from the base station and transmit it to the UE, and amplify the signal transmitted from the UE and transmit the amplified signal to the base station. That is, NCR can simply amplify and transmit the signal or channel transmitted and received between the base station and the UE without detecting or decoding the signal. Therefore, from the perspective of the UE, it is not known whether the NCR is involved in the communication between the base station and the terminal. In other words, from the perspective of the UE, the base station and the NCR cannot be distinguished, and the NCR may look like a base station. Because the UE does not require any additional information or operation for the NCR, the NCR can be supported in any version of the terminal.

[0267] As described above, from the perspective of the base station, the NCR can be regarded as a general UE. When the NCR is installed for the first time, the NCR can perform initial access to the base station like a general UE, and after making a high-level connection (e.g., RRC connection), the NCR can receive configurations that can be received by the UE from the base station. After connecting to the base station, the NCR can amplify and transmit. From the perspective of the base station, it is necessary to know whether the UE is directly connected to the base station or connected through the NCR. When the UE is within the coverage of the NCR, the UE can communicate with the base station through the NCR, and the base station can recognize this through the implementation method.

[0268] The base station can know which UE communicates through which NCR, but the NCR cannot know this fact. From the perspective of the NCR, no matter which UE is within its coverage, operations for amplifying and sending signals to the UE as controlled by the base station can be performed. In order for the base station to control the NCR, a control signal similar to DCI may be required. In the present disclosure, for convenience, this control signal is defined as side control information (SCI). SCI is not limited to the terms described later in this disclosure, and other terms with equivalent technical meanings may be used, such as repeater-DCI (R-DCI), repeater control information (RCI) and network control repeater control information (NCI). SCI refers to a control channel transmitted by the base station for controlling the NCR, and is an unknown signal from the perspective of the terminal, and can only be identified by the base station and the NCR.

[0269] Fig.12 An example of transmission and reception related to the NCR when the NCR is relayed between a base station and a UE according to an embodiment of the present disclosure is shown.

[0270] refer to Fig.12 , NCR 12-02 can relay communications (e.g., downlink, uplink) between base station 12-01 and UE 12-03. In the case of a downlink, the NCR can receive a downlink signal (12-11) sent from the base station, amplify the downlink signal and transmit it to the UE (12-12). In this case, the NCR can detect an SCI (12-31) from the base station that is configured to indicate the operation of the NCR. In the case of an uplink, the NCR can receive an uplink signal (12-22) sent from the UE, amplify the uplink signal and transmit it to the base station (12-21). In this case, the NCR can transmit uplink feedback or SRS for SCI or high-level control to the base station (12-32). Assuming that the NCR-MT part of the NCR is the same as a general terminal, it is a reasonable assumption that the NCR itself transmits uplink feedback.

[0271] In the downlink, the NCR can amplify the downlink signal and transmit it to the UE while detecting the SCI. From the perspective of the NCR, the above operation is possible when the SCI can be searched while performing the amplification and forwarding operation. Since the SCI search requires low complexity, the NCR will be able to perform the above operation without additional cost. On the other hand, the operation of the NCR itself transmitting the uplink feedback in the uplink and amplifying and forwarding the uplink signal of the UE at the same time can vary according to the implementation mode of the NCR.

[0272] Fig.13 An example of uplink transmission according to an RF chain when an NCR is relayed between a base station and a UE according to an embodiment of the present disclosure is shown.

[0273] refer to Fig.13 , UE 13-01 can receive the relay from NCR 13-02 to transmit the uplink signal to the base station 13-03. Fig.13 13-00 represents an example of a case where NCR-MT 13-04 and NCR-FU 13-05 are respectively connected to different RF chains 13-06, and 13-10 represents an example of a case where NCR-MT and NCR-FU are connected to the same RF chain. The RF chain is a functional configuration in which a single radio link and a series of RF processing elements (e.g., antenna, power amplifier, mixer) are connected like a chain, and are usually converted into analog signals at the digital stage, and then the frequency is increased and the signal is sent through several filters. Generally speaking, one RF chain is used for one stream. Therefore, in 13-00, since the signal transmitted by the UE and the signal transmitted by the NCR-MT in the uplink are transmitted to the base station through different RF chains, the signals can be transmitted in different frequency domains at the same time. On the other hand, when the signal transmitted by the UE and the signal transmitted by the NCR-MT in 13-10 are regarded as different streams, they cannot be transmitted in the same RF chain at the same time. Therefore, in case 13-10, the base station needs to instruct the NCR to transmit the signals of the UE and the NCR-MT at different times. Without such an indication, the NCR must support multiple terminals, and considering the environment in which multiple services (such as eMBB and URLLC) are dynamically managed in the NR system, conflicts may occur because the signals of the UE and the NCR-MT are scheduled at the same time. In this case, it is necessary to define which operation the NCR should perform.

[0274] As an embodiment of the present disclosure, a method for preventing data / signals of a network-controlled relay from colliding with data / signals of a UE in an uplink timeslot will be described.

[0275] In the current NR system, resources can be allocated to the UE periodically, semi-persistently or dynamically for signal transmission and reception. Resources can also be allocated to the NCR periodically, semi-persistently or dynamically like the terminal. As mentioned above, when the NCR uses one RF chain, there may be a problem that the NCR amplifies and transmits the uplink signal of the UE and cannot transmit the NCR-MT signal at the same time. Because the NCR does not know what kind of resources the UE being relayed is configured with, it can automatically give priority to the resources of the NCR unless an instruction is received to cancel the resources allocated to the NCR. The situation where two signals collide can be regarded as the four situations in Table 19.

[0276] Table 19 shows an example of a scenario where uplink data / signals of the UE and uplink data / signals of the NCR-MT overlap.

[0277]

Table 19

[0278]

[0279]

[0280] In Table 19, Case 1 is a case where both the NCR-MT and the UE of the NCR dynamically schedule signals, and may indicate a case where the resources allocated to the NCR-MT and the resources allocated to the UE overlap at least one symbol in the same time slot in the uplink time slot. Since both the NCR-MT and the UE are dynamically scheduled signals, when the number of UEs relayed by the NCR is small, the probability of a conflict in time will be small. However, when the number of terminals relayed by the NCR is large and the stability and speed of the terminals should be guaranteed, a conflict with the signal from the NCR may occur. Therefore, in Case 1, it can be seen that the UE's signal is given priority, and it may be necessary to add an uplink cancellation operation instruction to the NCR.

[0281] Case 2 represents the situation that the periodic / semi-persistently scheduled signal of the NCR-MT of the NCR and the dynamically scheduled signal of the UE conflict in time. In this case, since the base station gives priority to the dynamic signal of the UE, it can be regarded as scheduling for the terminal, and it may be necessary to add an uplink cancellation operation instruction to the NCR.

[0282] Case 3 is the case where the dynamically scheduled signal of the NCR-MT of the NCR and the periodically / semi-persistently scheduled signal of the UE conflict in time. In this case, the NCR-MT signal of the NCR can be given priority, and the NCR can transmit the NCR-MT signal without additional operation support.

[0283] Case 4 represents the case where the periodic / semi-persistently scheduled signal of the NCR-MT of the NCR and the periodic / semi-persistently scheduled signal of the UE conflict in time. In this case, when the base station gives priority to the signal of the terminal, it may be necessary to add an uplink cancellation operation instruction to the NCR.

[0284] In the proposed method and / or the embodiments described below, cases 1, 2, and 4 among the four cases mentioned in Table 19 are assumed and described. Hereinafter, in the present disclosure, a method for transmitting an NCR-MT signal of an NCR and a signal of a UE will be described for the above cases.

[0285] Method 1: Dedicated time slot for repeater UL signal transmission

[0286] For cases 1, 2, and 4, a time slot for transmitting an uplink signal may be configured from the base station to the NCR-MT of the NCR through high-layer signaling. In the present disclosure, for ease of description, the corresponding time slot will be referred to as an "NCR dedicated time slot". However, it is not limited to the terms described later in the present disclosure, and other terms with equivalent technical meanings may be used. The NCR dedicated time slot may mean a time slot in which the NCR does not perform amplification and forwarding operations on a signal transmitted by a UE, and may be configured to transmit uplink signals of the NCR-MT of the NCR, such as PUCCH, PUSCH, PRACH, and SRS. The NCR may not expect uplink signals for the NCR to be scheduled in time slots other than the NCR dedicated time slots.

[0287] Fig.14 An example of a case in which an NCR dedicated time slot is configured by higher layer signaling according to an embodiment of the present disclosure is shown.

[0288] refer to Fig.14 The duration 14-01 and period 14-02 of the NCR dedicated time slot can be configured by high-level signaling. The NCR can obtain the above information in time slots through high-level parameters, such as the duration and period parameters configured under the NCR dedicated time slot. In addition, the duration of the configured period can be assumed to be half a frame.

[0289] NCR may not assume NCR dedicated time slots under the following conditions:

[0290] - When the NCR dedicated slot overlaps with the SIB1 or SSB configured to ssb-PositionsInBurst of ServingCellConfigCommon for at least one symbol,

[0291] - When the NCR dedicated slot overlaps with the CORESET of the Type0-PDCCH CSS set configured to searchSpaceZero of pdcch-ConfigSIB1 or searchSpaceSIB1 of PDCCH-ConfigCommon in the MIB for at least one symbol,

[0292] - when the downlink timeslot is configured with the higher layer parameter tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated, and / or

[0293] - When the higher layer parameter SlotFormatIndicator is configured and a downlink slot is indicated in the SFI Index field of DCI format 2_0.

[0294] That is, the NCR may transmit uplink signals in time slots other than time slots satisfying the above conditions among the configured NCR dedicated time slots.

[0295] In this method 1, the NCR dedicated time slot can be interpreted as the NCR transmission symbol or symbol set in the NCR dedicated time slot. That is, the NCR can transmit the uplink signal of the NCR in some symbols or some symbol sets of the NCR dedicated time slot. The NCR transmission symbol or symbol set in the NCR dedicated time slot can be expressed as an NCR dedicated symbol or an NCR dedicated symbol set.

[0296] In this method 1, the NCR transmission symbol (set) can be located in the time domain satisfying the following.

[0297] For example, as a first position, the NCR transmit symbol (set) may be located within a flexible symbol. Here, the flexible symbol may be a flexible symbol configured according to tdd-UL-DL-ConfigurationCommon or ServingCellConfigurCommon of SIB1. The base station may not schedule an uplink signal to the UE in the flexible symbol, and the base station may schedule the NCR in the flexible symbol to transmit the uplink signal of the NCR. For example, when there are multiple consecutive flexible symbols, the last symbol in the flexible symbol may be determined as the NCR transmit symbol (set). That is, it may be assumed in the NCR that the flexible symbol cannot be just after the NCR transmit symbol (set).

[0298] As another example, as a second position, the NCR transmit symbol (set) may be an uplink symbol or symbol set just after the flexible symbol. That is, it may be configured in the order of flexible symbol-NCR transmit symbol (set)-uplink symbol. In this case, the UE may not be able to receive the scheduling of the uplink signal in the uplink symbol immediately following the flexible symbol, and may use this symbol as the RX to TX switching time.

[0299] For another example, as a third position, the NCR transmit symbol (set) may be an uplink symbol or symbol set just before the flexible symbol. That is, it may be configured in the order of uplink flexible symbol-NCR transmit symbol (set)-downlink symbol. In this case, the UE may not be able to receive the scheduling of the uplink signal in the uplink symbol immediately preceding the downlink symbol, and may use the symbol as the TX to RX switching time.

[0300] In method 1, a dedicated NCR time slot and uplink are configured from the base station to the NCR, and uplink transmission of the NCR is permitted according to the configuration. This can be selectively used according to the channel / signal transmitted by the NCR.

[0301] More specifically, the NCR may receive a periodic uplink transmission configuration from the base station through high-layer signaling. For example, the NCR may be configured with periodic PUSCH (or unlicensed PUSCH), periodic PUCCH (or HARQ-ACK transmission of SPS PDSCH, SR transmission, periodic CSI measurement transmission, etc.), and periodic SRS transmission. The transmission of periodic signals configured by high-layer signaling may be implemented in NCR-dedicated time slots or symbols (sets). That is, when a high-layer periodic signal is included in an NCR-dedicated time slot, symbol (set), the NCR may transmit a high-layer periodic signal, otherwise, some or all of the periodic signals configured to the high layer may not be transmitted.

[0302] In the case of periodic PUSCH (or unlicensed PUSCH) and periodic PUCCH (or HARQ-ACK transmission, SR transmission, periodic CSI measurement transmission, etc. of SPS PDSCH) within a time slot, when the NCR dedicated time slot and symbol (set) does not even include one symbol of periodic PUCCH / periodic PUSCH, the periodic PUSCH and periodic PUCCH in the time slot may not be transmitted.

[0303] In case of periodic SRS within one slot, when even one symbol is not included in the NCR dedicated slot, symbol (set), SRS is not transmitted in symbols not included in the slot but may be transmitted in symbols included.

[0304] More specifically, the NCR can be instructed to transmit an uplink channel / signal from the base station through PDCCH (or DCI format). In this case, as indicated by the base station, the NCR can transmit the uplink channel / signal indicated on the PDCCH. In this case, regardless of the previous NCR dedicated time slot or symbol (set), the NCR can be transmitted in the uplink. However, when the indicated uplink channel / signal overlaps with the downlink symbol, the uplink channel / signal may not be transmitted on the symbol.

[0305] Here, the downlink symbols may include SSB symbols configured in ssb-PositionsInBurst of SIB1 or ServingCellConfigCommon, and downlink symbols configured in tdd-UL-DL-ConfigurationCommon to tdd-UL-DL-ConfigurationDedicated.

[0306] Method 2: Two-step UL signal cancellation and retransmission

[0307] For cases 1, 2, and 4, the NCR may receive an instruction from the base station to cancel the uplink signal to be transmitted in two steps, and retransmit the canceled uplink signal. The first step is that the NCR receives an instruction from the base station to cancel the uplink signal scheduled by the NCR and performs a cancel operation, and the second step is that the NCR performs a retransmission operation.

[0308] As a first step, the NCR may receive a UL cancellation indication (UL CI) in DCI format 2_4 for an uplink signal to be transmitted (e.g., PUCCH, PUSCH, and SRS), and the NCR may cancel the uplink signal based on the UL CI. In the existing UL CI, when the HARQ-ACK contained in the PUCCH of the eMBB UE is canceled, many PDSCHs should be retransmitted due to the nature of the eMBB service, so PUCCH cancellation is excluded. However, since the NCR has a small amount of data transmission unlike the eMBB UE, it may be reasonable to support PUCCH cancellation. PUCCH may be newly included in the signal that the existing UL CI can cancel, and the operation of canceling the uplink signal based on the UL CI may be performed according to the existing method.

[0309] As a second step, the retransmission operation after the cancellation operation can be divided differently according to situations.

[0310] In the case of case 1, the dynamic uplink signal of the NCR may include PUCCH, PUSCH or SRS, including HARQ-ACK information. In this case, since the SRS has a low priority, the base station may additionally indicate SRS transmission later. On the other hand, when the base station operates the NCR, the HARQ-ACK information may be of great significance. For example, when the NCR is based on the symbol of the PUCCH containing HARQ-ACK information corresponding to the SCI reception or the symbol of the PUCCH containing HARQ-ACK information corresponding to the PDSCH reception containing MAC-CE information in the beam operation, the NCR sending the HARQ-ACK information to the base station may be regarded as an important operation. Therefore, the base station may instruct the NCR to retransmit the HARQ-ACK information, and the retransmission of the HARQ-ACK information may be performed according to the operation of retransmitting the existing HARQ-ACK codebook.

[0311] In cases 2 and 4, the periodic / semi-persistent uplink signal of the NCR may include PUCCH or PUSCH and SRS, which includes HARQ-ACK information, scheduling request or CSI report corresponding to SPS PDSCH reception. Even if the base station does not otherwise indicate retransmission, the periodic / semi-persistent uplink signal of the NCR may be retransmitted in the next cycle. Exceptionally, the PUCCH including HARQ-ACK information corresponding to SPS PDSCH reception may be transmitted in the nearest uplink timeslot after cancellation by applying HARQ-ACK delay operation for the existing SPS PDSCH.

[0312] Method 3: One-step UL signal cancellation and retransmission

[0313] In general, when the NCR relays between a base station and multiple terminals, it is necessary to perform relaying by using different beams for multiple terminals in a timely manner. In this case, the NCR can detect DCI for scheduling PDSCH including SCI or MAC-CE for beam adjustment in the downlink. As feedback to the signaling, the NCR can transmit a PUCCH including HARQ-ACK information for SCI or PDSCH to the base station. In addition, since multiple terminals send data or feedback information in the uplink, the probability of overlap between the NCR-MT signal of the NCR and the signal of the UE in the time domain can be increased. When a conflict occurs between the NCR-MT signal of the NCR and the signal of the UE and method 2 is applied, the base station should transmit SCI (or DCI) to the NCR twice in order to cancel and retransmit the NCR-MT signal of the NCR.

[0314] However, in case 1, the probability that cancellation and retransmission occur continuously is high. The reason is that, as described above, when the NCR relays the UE, more cases of detecting the DCI of the scheduled PDSCH including the SCI or MAC-CE occur. Therefore, if cancellation and retransmission occur continuously, as in method 2, the base station indicates both cancellation and retransmission with one SCI instead of indicating each step with a different SCI (or DCI) can produce the effect of reducing the burden of the NCR operation of the base station. Hereinafter, in method 3 of the present disclosure, the operation of both cancellation and retransmission of the uplink signal of the NCR indicated with one SCI will be described.

[0315] As an example of method 3, an example of canceling and retransmitting HARQ-ACK information of case 1 will be mainly described, but the scope of the present disclosure is not limited thereto and may be applied to cases 2 and 4.

[0316] Since the base station operates multiple NCRs and the number and services of relay terminals differ according to each NCR, it is necessary to discard the SCI according to the situation of the NCR. Therefore, it is more reasonable that the SCI indicating cancellation and retransmission is indicated as UE-specific or relay-specific, rather than giving information to all NCRs in a group-common manner. The NCR can expect / perform the following series of operations.

[0317] Operation 1. When the NCR is configured for one-step cancellation and retransmission through high-layer signaling (e.g., RRC) (e.g., onestep-UL-CI-Re), the NCR may be configured with a search space set in which the NCR detects an SCI scrambled with a C-RNTI or an MCS-RNTI. When high-layer signaling is configured and the field (e.g., UL-CI-Re field) of the detected SCI indicating one-step cancellation and retransmission is "1", the NCR may be indicated as a time region for canceling the uplink signal of the NCR-MT. For example, the duration of the time region to be canceled may be configured in symbol units in high-layer parameters. In addition, the starting symbol of the time region to be canceled may start after Tproc, rather than the last symbol of the PDCCH providing the detected SCI. Tproc may mean the minimum time required for the NCR to decode the PDCCH. For example, Tproc may be configured in symbol units, and the Tproc value may be determined based on the repeater capability. When a time region for canceling uplink accompanied by SCI and a scheduled PUCCH or PUSCH overlap at least one symbol, the NCR may not transmit the PUCCH or PUSCH to the base station.

[0318] Operation 2. After the NCR detects SCI in slot n and performs operation 1 (eg, cancellation of uplink transmission) in slot m, the NCR may retransmit the PUCCH or PUSCH including the cancelled HARQ-ACK information in slot n+k. Slot n+k may be located after slot m.

[0319] Fig.15 An example of an operation of canceling and retransmitting uplink transmission of an NCR according to an embodiment of the present disclosure is shown.

[0320] refer to Fig.15 , Operation 2 of NCR in Method 3 will be described in detail. NCR may expect one of Operation 2-1 (15-01) and Operation 2-2 (15-11).

[0321] - Operation 2-1. Reference Fig.15 15-01, the NCR may detect SCI 15-02 of which the field indicating one-step cancellation and retransmission is "1" in slot n 15-05, and discard PUCCH 15-03 in slot m 15-06. After that, the NCR may retransmit PUCCH 15-04 in slot n+k 15-07. In this case, k may be configured in units of symbols or slots by the field value of SCI.

[0322] - Operation 2-2. Reference Fig.15 15-11, the NCR may detect SCI 15-12 in which the field indicating one-step cancellation and retransmission is "1" in time slot n, and discard PUCCH 15-13 in time slot m. In this case, the NCR may assume that the time slot in which the PUCCH is to be retransmitted is a "non-numeric value". The NCR may detect DCI or SCI 15-14 that schedules PDSCH after time slot m, and when the DCI or SCI indicates the PUCCH resource as an "applicable value", the HARQ-ACK information of the canceled PUCCH 15-13 is multiplexed to PUCCH 15-15 and transmitted in time slot L 15-16.

[0323] Operation 3. The NCR may perform the operation for canceling the uplink signal in operation 1, determine the time resource for retransmission in operation 2, and then perform operation 3 (eg, retransmission). In operation 3, the NCR may anticipate one of the following operations.

[0324] - Operation 3-1. Not only HARQ-ACK information but also other UCI types (eg, scheduling request, CSI report) may be included in the retransmitted PUCCHs 15-04 and 15-15.

[0325] - Operation 3-2. Only HARQ-ACK information may be included in the retransmitted PUCCHs 15-04 and 15-15 and retransmitted. Other UCI types (eg, scheduling request, CSI report) not included may be discarded.

[0326] Operation 4. When a time-frequency region for canceling uplink accompanied by SCI overlaps with PUCCH or PUSCH for at least one symbol in a slot where retransmission is to be performed, the NCR may anticipate one of the following operations.

[0327] - Operation 4-1. The NCR may discard the PUCCH or PUSCH that overlaps the time-frequency region with at least one symbol without further retransmission.

[0328] - Operation 4-2. When the "current number of retransmission operations" is less than the "maximum number of retransmission operations" C, the NCR may restart from operation 1 and add 1 to the "current retransmission count". The "maximum number of retransmission operations" C may be configured by higher layer signaling. When the "current number of retransmission operations" exceeds the "maximum number of retransmission operations" C, the NCR may discard the PUCCH or PUSCH without further retransmission.

[0329] - Operation 4-3. Starting from the last symbol of the PDCCH providing the SCI that initially indicates cancellation and retransmission, the maximum deferral window may be configured in units of symbols or slots through higher layer signaling. When the PUCCH or PUSCH corresponding to operation 4 is within the maximum deferral window, operation 1 may be restarted.

[0330] Next, the configuration of a flexible symbol of NCR according to an embodiment of the present disclosure will be described.

[0331] In a 5G communication system, a traditional UE can be instructed to dynamically change the downlink signal transmission period and the uplink signal transmission period. To this end, the base station can indicate to the UE through a slot format indicator (SFI) whether each of the OFDM symbols that make up a time slot is a downlink symbol, an uplink symbol, or a flexible symbol. Here, a flexible symbol may refer to a symbol that is neither a downlink symbol nor an uplink symbol, or a symbol that can be changed to a downlink or uplink symbol through UE-specific control information or scheduling information. In this case, the flexible symbol may include gap protection necessary in the process of switching from downlink to uplink.

[0332] The UE receiving the slot format indicator may receive a downlink signal from the base station in the symbol indicated by the downlink symbol, and transmit an uplink signal to the base station in the symbol indicated by the uplink symbol. For the symbol indicated as a flexible symbol, the UE may at least perform a PDCCH monitoring operation, and receive a downlink signal from the base station through another indicator (e.g., DCI) (e.g., when DCI format 1_0 or 1_1 is received), or transmit an uplink signal to the base station in a flexible symbol (e.g., when DCI format 0_0 or 0_1 is received).

[0333] refer to Fig.11 In the first step, cell-specific configuration information 1110 for configuring the uplink-downlink in a semi-static manner may be configured. For example, the uplink-downlink of a symbol / time slot may be configured through system information such as SIB. Specifically, the cell-specific uplink-downlink configuration information 1110 in the system information may include uplink-downlink mode information and information indicating a reference subcarrier spacing. The uplink-downlink mode information may indicate a transmission periodicity 1103 for each mode, the number of consecutive complete DL time slots 1111 at the beginning of each DL-UL mode, the number of consecutive DL symbols 1112 at the beginning of a time slot after the last complete DL time slot, the number of consecutive complete UL time slots 1113 at the end of each DL-UL mode, and the number of symbols in the previous time slot (the number of consecutive UL symbols at the end of a time slot before the first complete UL time slot) 1114. In this case, the UE may determine a time slot / symbol that is not indicated as an uplink or downlink as a flexible time slot / symbol.

[0334] As a second step, UE-specific configuration information 1120 transmitted through UE-specific high-layer signaling (e.g., RRC signaling) may indicate symbols configured for downlink or uplink in the flexible time slot or the time slots 1121 and 1122 including flexible symbols. For example, the UE-specific uplink-downlink configuration information 1120 may include a time slot index indicating the time slots 1121 and 1122 including flexible symbols, the number of consecutive DL symbols at the beginning of the time slot (1123, 1125), and the number of consecutive UL symbols at the end of the time slot (1124, 1126), or may include information indicating the entire downlink or information indicating the entire uplink for each time slot. In this case, the symbol / time slot configured to the uplink or downlink through the cell-specific configuration information 1110 of the first step cannot be changed to the downlink or uplink through the UE-specific high-layer signaling 1120.

[0335] As a third step, in order to dynamically change the downlink signal transmission period and the uplink signal transmission period, the downlink control information of the downlink control channel may include a time slot format indicator 1130, which indicates whether each symbol is a downlink symbol, an uplink symbol or a flexible symbol in each of a plurality of time slots starting from the time slot in which the UE detects the downlink control information. In this case, for symbols / time slots configured to the uplink or downlink in the first and second steps, the time slot format indicator may not indicate whether they are downlink or uplink. In the first and second steps, the time slot format of each time slot 1131 or 1132 including at least one symbol that is not configured to the uplink or downlink may be indicated by the corresponding downlink control information.

[0336] As described above, the UE can know whether each symbol is a downlink symbol, an uplink symbol or a flexible symbol through high-layer signaling or a slot format indicator. The UE can use the uplink or downlink in the flexible symbol according to the instruction of the base station, and a gap period may be necessary in the process of switching from downlink to uplink.

[0337] NCR can also be configured for uplink and downlink, just like existing terminals, and in some cases, can be dynamically indicated. NCR can perform operations of receiving signals from a base station in a downlink and amplifying and forwarding the signals to a UE, and perform operations of receiving signals from a UE in the opposite direction in an uplink and amplifying and forwarding the signals to a base station. However, while it is expected that NCR operates explicitly for uplink and downlink symbols, the operation of NCR for flexible symbols is not clear.

[0338] Fig.16 An example of an uplink-downlink configuration of an NCR according to an embodiment of the present disclosure is shown.

[0339] refer to Fig.16, in a state where the NCR is configured for uplink and downlink by the cell common signal 16-01, UE 1 16-02 and UE 2 16-03 may be indicated by a time slot format indicator through a terminal-specific configuration. UE 1 and UE 2 are respectively indicated to use downlink 16-05 and uplink 16-06 in a terminal-specific manner in the flexible symbol area 16-04 set for the cell common. In this case, the NCR should perform a downlink operation on the symbol corresponding to 16-05 and an uplink operation on the symbol corresponding to symbol 16-06. However, from the perspective of the NCR, since the UE-specific configuration is unknown, the UE-specific configuration is not known until the downlink operation is performed and the uplink is switched. In other words, from the perspective of the NCR, if there is no additional configuration or instruction in the flexible symbol 16-04, the downlink / uplink switching time may be unclear.

[0340] In order to provide a clear switching time point for the flexible symbols of the NCR, the base station can configure the switching time point in units of symbols to the NCR through high-layer signaling.

[0341] Fig.17 An example of configuring an uplink-downlink switching time point of an NCR according to an embodiment of the present disclosure is shown.

[0342] refer to Fig.17 , when the switching time point is configured to the NCR through high-layer signaling, the NCR may configure the switching time along with the cell-specific signal 17-01 and the relay-specific signal 17-11. For example, in the case of 17-01, the NCR may be configured with up to X symbols 17-02 due to a cell-specific signal (e.g., SIB1), and it is expected that the NCR may switch to the uplink after X symbols from the last symbol configured as the downlink 17-03. That is, for the NCR, the X symbols from the last symbol configured as the downlink may be assumed to be the downlink, and the subsequent symbols may be assumed to be the uplink. For example, in the case of 17-11, the NCR may be configured with up to Y symbols 17-12 due to a relay-specific signal (e.g., RRC), and it is expected that the NCR may switch to the uplink after Y symbols from the last symbol configured as the downlink.

[0343] For example, when the switching point is configured with a cell-specific signal and the switching point is configured with a relay-specific signal, the NCR may follow the switching point of the relay-specific signal.

[0344] When the NCR has not received the switching time point or when the configured number of X or Y symbols is greater than the configured number of flexible symbols 17-04, the NCR may follow the following operations for the switching time point:

[0345] - switching from downlink to uplink in the first symbol after the last symbol of the configured downlink,

[0346] - switching from downlink to uplink in the last symbol before the first symbol of the configured uplink, or

[0347] - Assuming the number of configured flexible symbols is A, switch from downlink to uplink at ceil(A / 2) or floor(A / 2) symbols after the last symbol of the configured downlink.

[0348] When the NCR is configured to switch to high-layer signaling, the switching time may be configured with a cell-specific signal, or the switching point may be configured with a repeater-specific signal. For example, the NCR may be configured up to X' symbols because of a cell-specific signal (e.g., SIB1), and the NCR may expect reception in the downlink from the first symbol configured to the uplink to X' symbols before. That is, the NCR may assume that the symbol before X' symbols from the first symbol configured as the uplink is a downlink. For example, the NCR may be configured up to Y' symbols because of a repeater-specific signal (e.g., RRC), and the NCR may expect reception in the downlink from the first symbol configured to the uplink to Y' symbols before. For example, when the switching point is configured with a cell-specific signal and the switching point is configured with a repeater-specific signal, the NCR may follow the switching point of the repeater-specific signal.

[0349] For example, when the switching point is configured with a cell-specific signal and the switching point is configured with a relay-specific signal, the NCR may follow the switching point of the relay-specific signal.

[0350] When the NCR is not configured with a transition time point or when the configured number of X' or Y' symbols is greater than the configured number of flexible symbols, the NCR may follow the following operations for the transition time point:

[0351] - switching from downlink to uplink in the first symbol after the last symbol of the configured downlink,

[0352] - switching from downlink to uplink in the last symbol before the first symbol of the configured uplink, or

[0353] - Assuming the number of configured flexible symbols is A, switch from downlink to uplink at ceil(A / 2) or floor(A / 2) symbols after the last symbol of the configured downlink.

[0354] Fig.18 A flow chart illustrating the operation of the NCR according to an embodiment of the present disclosure is shown.

[0355] Fig.18 The operations may be performed according to the embodiments and / or methods described herein. In some cases, the Fig.18 Some operations, and two or more operations can be combined and performed as one operation. In addition, Fig.18 The order of operations can be changed.

[0356] In operation 1810, the NCR may receive control information (e.g., SCI or DCI) from a base station. For example, the control information may include information associated with cancellation and retransmission of uplink transmission of the NCR. For example, the uplink transmission of the NCR may include PUCCH transmission or PUSCH transmission.

[0357] The NCR may identify a first duration for cancellation of uplink transmission based on the control information in operation 1820. The first duration may start after a specific time (eg, Tproc) from the last symbol of the PDCCH including the control information.

[0358] In operation 1830, the NCR may cancel uplink transmission in the first duration. For example, in the case where the first duration overlaps at least one symbol with the PUSCH or PUCCH of the NCR, the NCR may not transmit the PUSCH or PUCCH to the base station.

[0359] In operation 1840, the NCR may identify a second duration for retransmitting the canceled uplink transmission. For example, when the second duration is in units of time slots, the time slot in which retransmission is performed may be determined by the time slot in which the control information is received and a value configured by a field included in the control information.

[0360] In operation 1850, the NCR may perform retransmission of the uplink transmission based on the second duration. For example, the canceled PUSCH or PUCCH may be retransmitted. The PUCCH or PUSCH may include HARQ-ACK information corresponding to the control information or HARQ-ACK information corresponding to the reception of the PDSCH containing MAC-CE information, and the scheduling request or CSI report may be excluded from the retransmission. Alternatively, the PUCCH or PUSCH may include both the HARQ-ACK information and the scheduling request or CSI report. In addition, the retransmission may be performed based on whether the current number of retransmission operations exceeds the maximum number of retransmission operations.

[0361] although Fig.18Not shown, but the NCR can receive information about the maximum deferral window from the base station. In addition, the NCR can receive second control information indicating the cancellation of the retransmission and the retransmission indicated by the control information. The NCR can identify a third duration for canceling the retransmission. In this case, if the second duration for retransmission overlaps with the third duration for cancellation of retransmission within the maximum deferral window, the NCR can perform an operation for retransmission (i.e., can perform retransmission). The NCR can receive information about dedicated time resources for uplink transmission of the NCR from the base station. The configuration of dedicated time resources can be based on the above-mentioned method 1. For example, dedicated time resources can be configured within flexible symbols configured for the UE.

[0362] although Fig.18 Although not shown in the figure, the NCR may receive information about the switching time between the uplink and the downlink from the base station. Based on this information, the NCR may perform uplink transmission or downlink transmission by identifying the switching time from the uplink to the downlink or from the downlink to the uplink.

[0363] The above embodiments and / or methods can be Fig.19 and Fig. 20 The terminal / base station / NCR is executed.

[0364] Fig.19 The structure of a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0365] refer to Fig.19 , the UE may include a UE receiver 19-00, a UE transmitter 19-10 and a UE processor (controller) 19-05.

[0366] For example, since the NCR relayed between the UE and the base station as described above looks like the UE from the perspective of the base station, in this case, Fig.19 The UE may be an NCR. For example, the NCR may include a receiver, a transmitter, and a processor (controller).

[0367] The UE receiver 19-00 and the UE transmitter 19-10 may be collectively referred to as a transceiver. The UE receiver 19-00, the UE transmitter 19-10, and the UE processor 19-05 may operate according to the communication method of the UE described above. However, the elements of the UE are not limited to the above examples. For example, the UE may include more or fewer elements (e.g., memory, etc.) than the above elements. In addition, the UE receiver 19-00, the UE transmitter 19-10, and the UE processor 19-05 may be implemented in the form of a single chip.

[0368] The UE receiver 19-00 and the UE transmitter 19-10 (or transceiver) can send signals to or receive signals from the base station. Here, the signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying the transmitted signal, an RF receiver for low-noise amplification and down-conversion of the received signal, etc. However, this is only an embodiment of the transceiver, and the elements of the transceiver are not limited to the RF transmitter and the RF receiver.

[0369] In addition, the transceiver can receive a signal through a wireless channel and output the received signal to the UE processor 19-05, and can transmit a signal output from the UE processor 19-05 through the wireless channel.

[0370] The memory (not shown) may store programs and data necessary for the operation of the UE. In addition, the memory may store control information or data included in a signal acquired by the UE. The memory may be configured as a storage medium such as a read-only memory (ROM), a random access memory (RAM), a hard disk, a compact disk (CD)-ROM, and a digital versatile disk (DVD), or a combination of storage media.

[0371] The UE processor 19-05 may control a series of processes so that the UE may operate according to the above-described embodiments. The UE processor 19-05 may be implemented as a controller or one or more processors.

[0372] Fig. 20 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown.

[0373] refer to Fig. 20 , the base station may include a base station receiver 20-00, a base station transmitter 20-10 and a base station processor (controller) 20-05.

[0374] For example, since the NCR relayed between the UE and the base station as described above looks like a base station from the perspective of the terminal, in this case, Fig. 20 The base station may be an NCR. For example, an NCR may include a receiver, a transmitter, and a processor (controller).

[0375] The base station receiver 20-00 and the base station transmitter 20-10 may be collectively referred to as a transceiver. The base station receiver 20-00, the base station transmitter 20-10 and the base station processor 20-05 of the base station may operate according to the communication method of the above-mentioned base station. However, the elements of the base station are not limited to the above-mentioned examples. For example, the base station may include more or less elements (e.g., memory, etc.) than the above-mentioned elements. In addition, the base station receiver 20-00, the base station transmitter 20-10 and the base station processor 20-05 may be implemented in the form of a single chip.

[0376] The base station receiver 20-00 and the base station transmitter 20-10 (or transceiver) can transmit signals to or receive signals from the UE. Here, the signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying the transmitted signal, an RF receiver for low-noise amplification and down-conversion of the received signal, etc. However, this is only an embodiment of the transceiver, and the elements of the transceiver are not limited to the RF transmitter and the RF receiver.

[0377] In addition, the transceiver can receive a signal through a wireless channel and output the received signal to the base station processor 20-05, and can transmit a signal output from the base station processor 20-05 through the wireless channel.

[0378] The memory (not shown) may store programs and data necessary for the operation of the base station. In addition, the memory may store control information or data included in the signal acquired by the base station. The memory may be configured as a storage medium such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

[0379] The base station processor 20-05 may control a series of processes so that the base station operates according to the above-described embodiments. The base station processor 20-05 may be implemented as a controller or one or more processors.

[0380] In the drawings describing the methods of the present disclosure, the order of description does not always correspond to the order of performing the steps of each method, and the sequential relationship between the steps may be changed or the steps may be performed in parallel.

[0381] Alternatively, in the drawings describing the method of the present disclosure, some elements may be omitted, and only some elements may be included therein without departing from the essential spirit and scope of the present disclosure.

[0382] Furthermore, in the method of the present disclosure, some or all of the contents of each embodiment may be combined without departing from the essential spirit and scope of the present disclosure.

[0383] Furthermore, although not illustrated in the present disclosure, a method using a separate table or information including at least one element included in the table proposed in the present disclosure is also possible.

[0384] While the disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a network control repeater (NCR) in a wireless communication system, the method comprising: receiving control information from a base station, the control information including information associated with cancellation and retransmission of uplink transmissions of the NCR; identifying a first duration for cancellation of the uplink transmission based on the control information; canceling the uplink transmission during the first duration; identifying a second duration for retransmission of the uplink transmission cancelled during the first duration; as well as Retransmission of the uplink transmission is performed based on the second duration.

2. The method according to claim 1, in, performing retransmission of the uplink transmission comprises transmitting a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) in a time slot, and The PUCCH or the PUSCH includes hybrid automatic repeat request-acknowledgement HARQ-ACK information corresponding to the control information.

3. The method according to claim 2, in, The time slot is determined based on the time slot in which the control information is received and a value configured by the control information, and The PUCCH or the PUSCH does not include a scheduling request and a channel state information CSI report.

4. The method of claim 1, further comprising: receiving information about a maximum deferral window from a base station, the maximum deferral window starting from a last symbol of the control information received; receiving second control information from the base station, the second control information comprising information associated with cancellation and retransmission of a retransmission indicated by the control information; as well as identifying a third duration for cancellation of retransmission based on the second control information, Wherein, in a case where the second duration overlaps with the third duration within the maximum deferral window, retransmission of the uplink transmission is performed.

5. The method of claim 1, further comprising: receiving from the base station information regarding dedicated time resources for the uplink transmission of the NCR, The dedicated time resource is configured within a flexible symbol for the terminal.

6. The method of claim 1, further comprising: Information related to a switching time between uplink and downlink is received from the base station.

7. A method performed by a base station in a wireless communication system, the method comprising: transmitting control information to a network control repeater NCR, said control information comprising information associated with cancellation and retransmission of uplink transmissions of said NCR; as well as receiving an uplink signal from the NCR based on a first duration, wherein the uplink transmission of the NCR is cancelled within a second duration for cancellation of the uplink transmission, the second duration being identified based on the control information, and Therein, the uplink signal corresponds to a retransmission of the uplink transmission cancelled during the second duration.

8. The method according to claim 7, in, The uplink signal is received on a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) in a time slot, and The PUCCH or the PUSCH includes hybrid automatic repeat request-acknowledgement HARQ-ACK information corresponding to the control information.

9. The method according to claim 8, in, The time slot is determined based on the time slot in which the control information is received and a value configured by the control information, and The PUCCH or the PUSCH does not include a scheduling request and a channel state information CSI report.

10. The method of claim 7, further comprising: transmitting information about a maximum deferral window to the NCR, the maximum deferral window starting from a last symbol at which the control information is received; as well as transmitting second control information to the NCR, the second control information including information associated with cancellation and retransmission of a retransmission indicated by the control information; wherein a third duration for cancellation of retransmission is identified based on the second control information, and Wherein, in a case where the first duration overlaps with the third duration within the maximum deferral window, the uplink signal cancelled during the second duration is received.

11. A network control repeater NCR in a wireless communication system, the NCR comprising: Transceiver; as well as a controller coupled to the transceiver and configured to: receiving control information from a base station, the control information including information associated with cancellation and retransmission of uplink transmissions of the NCR, identifying a first duration for cancellation of the uplink transmission based on the control information, canceling the uplink transmission during the first duration, identifying a second duration for retransmission of the uplink transmission cancelled during the first duration, and Retransmission of the uplink transmission is performed based on the second duration.

12. The NCR according to claim 11, in, For performing retransmission of the uplink transmission, the controller is configured to transmit a physical uplink control channel PUCCH or a physical uplink shared channel PUSCH in a time slot, and The PUCCH or the PUSCH includes hybrid automatic repeat request-acknowledgement HARQ-ACK information corresponding to the control information.

13. The NCR according to claim 12, in, The time slot is determined based on the time slot in which the control information is received and a value configured by the control information, and The PUCCH or the PUSCH does not include a scheduling request and a channel state information CSI report.

14. The NCR according to claim 11, in, The controller is further configured to: receiving information about a maximum deferral window from a base station, the maximum deferral window starting from a last symbol of the control information received, receiving second control information from the base station, the second control information including information associated with cancellation and retransmission of a retransmission indicated by the control information, and identifying a third duration for cancellation of retransmission based on the second control information, Wherein, in a case where the second duration overlaps with the third duration within the maximum deferral window, retransmission of the uplink transmission is performed.

15. A base station in a wireless communication system, the base station comprising: Transceiver; as well as a controller coupled to the transceiver and configured to: transmitting control information to a network control repeater NCR, said control information comprising information associated with cancellation and retransmission of uplink transmissions of said NCR, and receiving an uplink signal from the NCR based on a first duration, wherein the uplink transmission of the NCR is cancelled within a second duration for cancellation of the uplink transmission, the second duration being identified based on the control information, and Therein, the uplink signal corresponds to a retransmission of the uplink transmission cancelled during the second duration.

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