Method for measuring and reporting channel state information for network cooperative communication

Abstract

The present disclosure relates to a communication method and system for integrating a fifth generation (5G) communication system with an Internet of Things (IoT) technology, wherein the fifth generation communication system is used to support a higher data 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, such as smart homes, smart buildings, smart cities, smart cars, connected cars, health care, digital education, smart retail, security and safety services. The present disclosure relates to a method for processing a control signal in a wireless communication system, and to a control signal processing method, the method comprising: receiving a first control signal sent from a base station; processing the received first control signal; and sending a second control signal generated based on the processing to the base station.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly to a method for a terminal to measure and report channel state information between a base station and the terminal to achieve higher reliability and throughput. Background Art

[0002] In order to meet the increased demand for wireless data services since the deployment of 4G communication systems, efforts have been made to develop an improved 5G or quasi-5G communication system. Therefore, 5G or quasi-5G communication systems are also referred to as "super 4G networks" or "post-LTE systems". 5G communication systems are considered to be implemented at higher frequency (millimeter wave) bands (e.g., 60GHz bands) to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple input multiple output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antenna technology are discussed in 5G communication systems. In addition, in 5G communication systems, based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), receiving end interference elimination, etc., the development of system network improvements is underway. In 5G systems, hybrid FSK with QAM modulation (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coded modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0003] The Internet, which is a human-centered connectivity network in which humans generate and consume information, has now evolved into the Internet of Things (IoT), in which distributed entities (such as things) exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is a combination of IoT technology and big data processing technology through connection with cloud servers. Since IoT specific implementation requires technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology", sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. have recently been studied. Such IoT environments can provide smart Internet technology services that create new value for human life by collecting and analyzing data generated between connected things. IoT can be applied to a variety of fields including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart appliances, and advanced medical services through the integration and combination between existing information technology (IT) and various industrial applications.

[0004] Therefore, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communications (MTC), and machine-to-machine (M2M) communications can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RANs) as an application of the above-mentioned big data processing technologies can also be considered as an example of the fusion of 5G technology and IoT technology.

[0005] The above information is presented only as background information to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be used as prior art for the present disclosure. Summary of the invention

[0006] Technical issues

[0007] According to the present disclosure, when network cooperation is used in a wireless communication system, the calculation time and amount of calculation required to measure and report channel state information can be determined more accurately.

[0008] Solution

[0009] According to one aspect of the present disclosure, a method performed by a terminal in a wireless communication system is provided, the method comprising: sending a terminal capability report including information on whether non-coherent joint transmission (NC-JT) channel state information (CSI) reporting is supported to a base station; receiving an NC-JT CSI report request from the base station based on the information included in the terminal capability report; determining whether to report NC-JT CSI based on the NC-JT report request; and sending an NC-JT CSI report to the base station based on the determination.

[0010] In an exemplary embodiment, it also includes: measuring NC-JT CSI; determining whether the number of channel state information reference signals (CSI-RS) used to report NC-JT CSI is greater than a threshold; and determining the number of CPUs used for NC-JT CSI reporting to the base station based on the determination.

[0011] In an exemplary embodiment, determining whether to report NC-JT CSI includes determining whether to report NC-JT CSI based on a CSI report, wherein the CSI report includes at least one of an instruction through an upper layer, an instruction through a media access control (MAC)-control element (CE), and an instruction through L1 signaling.

[0012] In an exemplary embodiment, determining whether to report NC-JT CSI includes determining whether to report NC-JT CSI based on at least one of: the number of CSI-RS used for NC-JT CSI reporting, the periodicity of NC-JT CSI reporting, and the number of resource sets or resource settings related to the CSI reporting settings for NC-JT CSI reporting.

[0013] In an exemplary embodiment, it also includes performing NC-JT transmission based on the NC-JT CSI report, wherein the NC-JT transmission is performed based on the resource allocation of each TRP (Tx / Rx point).

[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 comprising: receiving a terminal capability report from a terminal including information on whether non-coherent joint transmission (NC-JT) channel state information (CSI) reporting is supported; sending an NC-JT CSI report request to the terminal based on the information included in the terminal capability report; and receiving an NC-JT CSI report from the terminal based on the NC-JT CSI report request, wherein whether to report the NC-JT CSI is determined by the terminal based on the NC-JT report request.

[0015] According to another aspect of the present disclosure, a terminal is provided, comprising: a transceiver capable of sending and receiving at least one signal; and a controller coupled to the transceiver and configured to: send a terminal capability report including information on whether non-coherent joint transmission (NC-JT) channel state information (CSI) reporting is supported to a base station; receive an NC-JT CSI report request from the base station based on the information included in the terminal capability report; determine whether to report the NC-JT CSI based on the NC-JT report request; and send the NC-JT CSI report to the base station based on the determination.

[0016] According to another aspect of the present disclosure, a base station is provided, comprising: a transceiver capable of sending and receiving at least one signal; and a controller coupled to the transceiver and configured to: receive a terminal capability report from a terminal including information on whether non-coherent joint transmission (NC-JT) channel state information (CSI) reporting is supported; send an NC-JT CSI report request to the terminal based on the information included in the terminal capability report; and receive an NC-JT CSI report from the terminal based on the NC-JT CSI report request, wherein whether to report the NC-JT CSI is determined by the terminal based on the NC-JT report request.

[0017] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used throughout this patent document: the terms "include" and "comprise" and their derivatives mean including but not limited to; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean include, included within, interconnected with, contain, contained within, connected to or connected with, coupled to or coupled with, communicable with, cooperating with, intertwined, juxtaposed, proximate to, bound to or bound with, having, having a property of, and the like; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two of hardware, firmware, or software. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.

[0018] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data or a part thereof suitable for implementation with a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disc (DVD) or any other type of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical or other communication links that transmit temporary electrical signals or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and rewritten later, such as rewritable optical disks or erasable memory devices.

[0019] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to both past and future tenses of such defined words and phrases.

[0020] Beneficial Effects

[0021] The present disclosure may provide a method for measuring and reporting channel state information between multiple transmission nodes and a terminal in a wireless communication system for network coordination. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

[0023] Figure 1 A basic structural diagram of a mobile communication system in time-frequency domain according to an embodiment is shown;

[0024] Figure 2 A diagram for explaining a frame, subframe, and slot structure of a mobile communication system according to an embodiment is shown;

[0025] Figure 3 A diagram showing an example of a configuration of a bandwidth part (BWP) in a wireless communication system according to an embodiment;

[0026] Figure 4 A diagram showing an example of configuring a control region of a downlink control channel in a wireless communication system according to an embodiment;

[0027] Figure 5 A view for explaining a structure of a downlink control channel of a mobile communication system according to an embodiment is shown;

[0028] Figure 6 A diagram showing an example of PDSCH frequency axis resource allocation in a wireless communication system according to one embodiment;

[0029] Figure 7 A diagram showing an example of physical downlink shared channel (PDSCH) timeline resource allocation in a wireless communication system according to one embodiment;

[0030] Figure 8 A diagram showing an example of performing time axis resource allocation according to subcarrier spacings of a data channel and a control channel in a wireless communication system according to an embodiment;

[0031] Fig. 9 A diagram showing an example of CPU occupancy time of a CSI report where the number of reports included in the CSI report is not configured as "None" according to some embodiments;

[0032] Fig.10 A diagram showing an example of CPU occupancy time of a CSI report where the number of reports included in the CSI report is configured as "none" according to some embodiments;

[0033] Fig.11 A diagram showing a base station and terminal protocol stack when performing single cell, carrier aggregation and dual connectivity according to some embodiments;

[0034] Fig.12 A diagram showing an example of antenna port configuration and resource allocation for cooperative communication according to some embodiments in a wireless communication system according to one embodiment;

[0035] Fig.13 A diagram showing an example of downlink control information (DCI) configuration for cooperative communication in a wireless communication system according to one embodiment;

[0036] Fig.14 A diagram showing a configuration example of a CSI framework for non-coherent joint transmission (NC-JT) CSI reporting according to one embodiment;

[0037] Fig.15 shows a flow chart of the NC-JT CSI reporting process according to one embodiment;

[0038] Fig.16 A diagram showing a terminal structure in a wireless communication system according to an embodiment; and

[0039] Fig.17 A diagram showing a structure of a base station in a wireless communication system according to an embodiment. DETAILED DESCRIPTION

[0040] Discussed below Figures 1 to 17 The various embodiments used to describe the principles of the present disclosure in this patent document are merely illustrative and should not be construed in any way to limit the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0041] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0042] In the process of describing the embodiments of the present disclosure, descriptions related to technical contents well-known in the art and not directly related to the present disclosure will be omitted. Such unnecessary descriptions are omitted to prevent the main idea of ​​the present disclosure from being obscured and to convey the main idea more clearly.

[0043] For the same reason, 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.

[0044] 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.

[0045] Here, it will 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-available or computer-readable memory that can instruct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-available or computer-readable memory produce a product including an instruction device for performing the functions specified in 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.

[0046] 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, the two frames shown in succession can in fact be performed substantially simultaneously, or the frame can sometimes be performed in reverse order, depending on the functions involved.

[0047] 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, "unit" does not always have a meaning limited to software or hardware. "Unit" can be constructed to be stored in an addressable storage medium or to execute one or more processors. Therefore, "unit" includes (for example) software element, object-oriented software element, class element or task element, process, function, attribute, program, subroutine, program code fragment, driver, firmware, microcode, circuit, data, database, data structure, table, array and parameter. The element and function provided by "unit" can be combined into a smaller number of elements or "units", or divided into a larger number of elements or "units". In addition, element and "unit" can be implemented as one or more CPUs in a reproduction device or a secure multimedia card. In addition, "unit" in an embodiment can include one or more processors.

[0048] Hereinafter, the working principle of the present disclosure will be described in detail in conjunction with the accompanying drawings. In the following description of the present disclosure, when the subject matter of the present disclosure may become quite 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 differ according to the user, the user's intention, or the habit. Therefore, the definition of the terms should be determined based on the content throughout the entire specification. Hereinafter, the base station is the subject that performs resource allocation of the terminal, and may be at least one of a gNode B (gNB), an eNode B (eNB), a node B, a base station (BS), a radio access unit, a base station controller, or 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, it is not limited to the above examples. Hereinafter, the present disclosure describes a technology for a terminal in a wireless communication system to receive broadcast information from a base station. The present disclosure relates to a communication technology and system for combining a 5th generation (5G) communication system with an Internet of Things (IoT) technology to support a higher data transmission rate after a 4th generation (4G) system. The present disclosure can be applied to smart services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail, security and safety-related services, etc.) based on 5G communication technology and IoT-related technology.

[0049] For convenience of explanation, terms related to broadcast information, terms related to control information, terms related to communication coverage, terms related to state changes (e.g., events), terms related to network entities, terms related to messages, terms related to device components, etc. used in the following description are exemplified. Therefore, the present disclosure is not limited to the terms described below, and other terms with equivalent technical meanings may be used.

[0050] Hereinafter, for convenience of description, some terms and names defined in the 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) standard may be used. However, the present disclosure is not limited to these terms and names and may be applied to systems conforming to other standards.

[0051] In addition to providing the original voice-based services, wireless communication systems have evolved into broadband wireless communication systems that provide high-speed and high-quality packet data services using communication standards such as High Speed ​​Packet Access (HSPA) of the 3rd Generation Partnership Project (3GPP), Long Term Evolution (LTE) or Evolved Universal Terrestrial Radio Access (E-UTRA), Advanced LTE (LTE-A), LTE-Pro, High Speed ​​Packet Data (HRPD) of 3GPP2, Ultra Mobile Broadband (UMB), and IEEE 802.16e.

[0052] As a representative example of a broadband wireless communication system, in the LTE system, an orthogonal frequency division multiplexing (OFDM) scheme is adopted in the downlink (DL) and a single carrier frequency division multiple access (SC-FDMA) scheme is adopted in the uplink (UL). The uplink refers to a radio link through which a terminal (user equipment (UE)) or a mobile station (MS) transmits data or a control signal to a base station (eNode B or base station (BS)), and the downlink refers to a radio link through which a base station transmits data or a control signal to a terminal. In this multiple access method, the data or control information of each user is usually divided by allocation and operation so that the time-frequency resources of the data or control information to be carried by each user do not overlap, that is, orthogonality is established.

[0053] As the future communication system after LTE, the 5G communication system should be able to freely reflect the various needs of users and service providers, and thus should support services that meet various needs. The services considered by the 5G communication system include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable low latency communication (URLLC), etc.

[0054] According to some embodiments, eMBB is intended to provide a more improved data transmission rate than existing 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 maximum data rate of 20Gbps in the downlink and a maximum data rate of 10Gbps in the uplink. At the same time, an increase in the actual perceived data rate of the terminal should be provided. In order to meet this demand, it is necessary to improve the transmission / reception technology, including more advanced multiple-input multiple-output (MIMO) transmission technology. In addition, by using a bandwidth wider than 20MHz in the 3GHz to 6GHz or 6GHz or higher frequency band, instead of the 2GHz band currently used by LTE, the data transmission speed required by the 5G communication system can be met.

[0055] Meanwhile, in 5G communication systems, mMTC is viewed as supporting application services such as the Internet of Things (IoT). In order to efficiently provide the Internet of Things, mMTC may be required to support access to large-scale terminals within a cell, improve the coverage of the terminal, improve battery life, and reduce terminal costs. The Internet of Things should be able to support a large number of terminals in a cell (e.g., 1,000,000 terminals / km2) when it is attached to various sensors and various devices to provide communication functions. In addition, due to the nature of the service, terminals supporting mMTC are likely to be located in shadowed areas that cannot be covered by the cell, such as the basement of a building, and therefore may require a wider coverage than other services provided by the 5G communication system. Since terminals supporting mMTC should be configured with low-cost terminals and the batteries of the terminals are difficult to replace frequently, very long battery life may be required.

[0056] Finally, URLLC is a cellular-based wireless communication service for specific purposes (mission critical), a service for remote control of robots or mechanical devices, industrial automation, drones, remote health control, emergency notifications, etc., and should provide ultra-low latency and ultra-high reliability communications. For example, services supporting URLLC should meet the requirements of an air interface delay of less than 0.5 milliseconds and a packet error rate of 10-5 or less. Therefore, for services supporting URLLC, the 5G system needs to provide a smaller transmission time interval (TTI) than other services, and also needs to design requirements to allocate wider 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 examples.

[0057] The services considered in the above 5G communication system should be provided by integrating with each other on the basis of a framework. That is, for efficient resource management and control, it is better to integrate, control and transmit each service as a system rather than operate separately.

[0058] In addition, in the following, the embodiments will be described as examples of LTE, LTE-A, LTE Pro or New Radio (NR) systems, but the embodiments may also be applied to other communication systems with similar technical backgrounds or channel types. In addition, the embodiments may be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure as judged by those skilled in the art.

[0059] The present disclosure relates to a method and apparatus for reporting channel state information in a wireless communication system to improve power saving efficiency of a terminal.

[0060] According to the present disclosure, when a terminal in a wireless communication system operates in a power saving mode, the power saving effect can be further improved by optimizing the channel state information reporting method accordingly.

[0061] Hereinafter, the framework structure of the 5G system will be described in more detail with reference to the accompanying drawings.

[0062] refer to Figure 1 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of the time domain and the frequency domain is a resource element (RE) 1-01, and can be defined as 1 orthogonal frequency division multiplexing (OFDM) symbol 1-02 on the time axis and 1 subcarrier 1-03 on the frequency axis. In the frequency domain, N_sc^RB (e.g., 12) consecutive REs can constitute a resource block (RB) 1-04. In one embodiment, multiple OFDM symbols can constitute a subframe 1-10.

[0063] Figure 2 A view for explaining a frame, a subframe, and a slot structure of a next generation mobile communication system according to an embodiment is shown.

[0064] refer to Figure 2 , a frame 2-00 may be composed of one or more subframes 2-01, and a subframe may be composed of one or more time slots 2-02. For example, a frame 2-00 may be defined as 10ms. A subframe 2-01 may be defined as 1ms, and in this case, a frame 2-00 may be composed of a total of 10 subframes 2-01. A time slot 2-02, 2-03 may be defined by 14 OFDM symbols (i.e., the number of symbols per time slot is 10). ). A subframe 2-01 may consist of one or more time slots 2-02, 2-03, and the number of time slots 2-02, 2-03 in each subframe 2-01 may be different according to the configured value μ2-04, 2-05 of the subcarrier spacing. Figure 2In the example of , the subcarrier spacing is configured as μ = 0 (2-04) and μ = 1 (2-05). When μ = 0 (2-04), one subframe 2-01 can be composed of one time slot 2-02, and when μ = 1 (2-05), one subframe 2-01 can be composed of two time slots 2-03. That is, the number of time slots per subframe is can vary according to the configured value μ of the subcarrier spacing and therefore the number of slots per frame Can vary. and μ is configured according to each subcarrier spacing and can be defined in the following [Table 1].

[0065] [Table 1]

[0066]

[0067] In NR, one component carrier (CC) or serving cell can be configured with up to 250 or more RBs. Therefore, when the terminal always receives the entire serving cell bandwidth (LTE), such as LTE, the power consumption of the terminal may be very large, and to solve this problem, the base station can configure one or more bandwidth parts (BWP) to the terminal to support the terminal to change the reception area in the cell. In NR, the base station can configure the "initial BWP" for the terminal through the master information block (MIB), that is, the bandwidth of CORESET#0 (or common search space, CSS). Then, the base station can configure the initial BWP (first BWP) of the terminal through radio resource control (RRC) signaling, and can notify the terminal of at least one BWP configuration information that can be indicated by downlink control information (DCI) in the future. Thereafter, the base station can notify the BWP ID through DCI to indicate which frequency band the terminal will use. If the terminal cannot receive DCI from the currently allocated BWP for a specific time or longer, the terminal can return to the "default BWP" and try to receive DCI.

[0068] Figure 3 A diagram showing an example of a configuration of a bandwidth part (BWP) in a wireless communication system according to an embodiment.

[0069] refer to Figure 3 , Figure 3 An example is shown in which the terminal bandwidth (3-00) is configured as two bandwidth parts, namely bandwidth part #1 (3-05) and bandwidth part #2 (3-10). The base station can configure one or more bandwidth parts for the terminal, and can configure the information shown in the following [Table 2] for each bandwidth part.

[0070] [Table 2]

[0071]

[0072] Of course, the present disclosure is not limited to the above examples, and in addition to the above configuration information, various parameters related to the bandwidth part may be configured to the terminal. The above information may be sent to the terminal by the base station through higher layer signaling, such as RRC signaling. At least one of the configured one or more bandwidth parts may be activated. Whether to activate the configured bandwidth part may be semi-statically sent from the base station to the terminal through RRC signaling, or may be dynamically sent through a MAC control element (CE) or DCI.

[0073] According to one embodiment, a terminal before a radio resource control (RRC) connection may receive an initial bandwidth part (initial BWP) for initial access from a base station through a master information block (MIB). More specifically, in order to receive system information required for initial access through the MIB in the initial access step (remaining system information; may correspond to RMSI or system information block (SIB) 1), the terminal may receive configuration information for a control region (control resource set, CORSET) and a search space through which a PDCCH may be transmitted. The control region and search space configured by the MIB may be respectively regarded as identifiers (ID) 0.

[0074] The base station may notify the terminal of configuration information such as frequency allocation information, time allocation information, and parameter set of control area #0 through MIB. In addition, the base station may notify the terminal of configuration information of the monitoring period and timing of control area #0, that is, configuration information of search space #0 through MIB. The terminal may regard the frequency domain of control area #0 configured to be obtained from MIB as the initial bandwidth part for initial access. At this time, the identifier (ID) of the initial bandwidth part may be regarded as 0.

[0075] The bandwidth portion supported by the above-mentioned next-generation mobile communication system (5G or NR system) can be used for various purposes.

[0076] For example, when the bandwidth supported by the terminal is less than the system bandwidth, the bandwidth supported by the terminal can be supported by configuring the bandwidth part. For example, in Table 2, the frequency position of the bandwidth part (configuration information 2) is configured to the terminal so that the terminal can send and receive data at a specific frequency position within the system bandwidth.

[0077] As another example, for the purpose of supporting different parameter sets, the base station may configure multiple bandwidth parts for the terminal. For example, in order to support data transmission and reception to any terminal using a subcarrier spacing of 15kHz and a subcarrier spacing of 30kHz, two bandwidth parts may be configured to use subcarrier spacings of 15kHz and 30kHz, respectively. Different bandwidth parts may be frequency division multiplexed (FDM), and when data is transmitted / received at a specific subcarrier spacing, the bandwidth part configured with the corresponding subcarrier spacing may be activated.

[0078] For another example, for the purpose of reducing the power consumption of the terminal, the base station can configure bandwidth parts with different sizes of bandwidth for the terminal. For example, if the terminal supports a very large bandwidth, such as a bandwidth of 100 MHz, and always sends / receives data with the corresponding bandwidth, it may cause very large power consumption. In particular, the terminal performs unnecessary downlink control channel monitoring of the large bandwidth of 100 MHz in the absence of business, which is very inefficient in terms of power consumption. Therefore, for the purpose of reducing the power consumption of the terminal, the base station can configure a bandwidth part with a relatively small bandwidth for the terminal, such as a bandwidth part of 20 MHz. In the absence of business, the terminal can perform monitoring operations in the 20 MHz bandwidth part, and when data occurs, the 100 MHz bandwidth part can be used to send / receive data according to the instructions of the base station.

[0079] In the method for configuring the above-mentioned bandwidth part, the terminal before the RRC connection can receive the configuration information of the initial bandwidth part through the master information block (MIB) in the initial access step. More specifically, the terminal can receive the control area (control resource set (CORESET)) for the downlink control channel from the MIB of the physical broadcast channel (PBCH), and the downlink control information (DCI) of the scheduling system information block (SIB) can be transmitted through the downlink control channel. The bandwidth of the control area configured as the MIB can be regarded as the initial bandwidth part, and the terminal can receive the PDSCH through which the SIB is sent through the configured initial bandwidth part. In addition to the purpose of receiving the SIB, the initial bandwidth part can also be used for other system information (OSI), paging and random access.

[0080] Hereinafter, a synchronization signal (SS) / PBCH block of a next-generation mobile communication system (5G or NR system) will be described.

[0081] The SS / PBCH block may denote a physical layer channel block consisting of a primary SS (PSS), a secondary SS (SSS), and a PBCH. More specifically, the SS / PBCH block may be defined as follows.

[0082] -PSS: A signal that serves as a downlink time / frequency synchronization reference and can provide some information of the cell ID.

[0083] -SSS: serves as a reference for downlink time / frequency synchronization and can provide the remaining cell ID information not provided by PSS. In addition, it can be used as a reference signal for PBCH demodulation.

[0084] -PBCH: can provide basic system information required for data channels and control channels of the transmitting / receiving terminal. The basic system information may include search space related control information indicating radio resource mapping information of the control channel, scheduling control information of a separate data channel for transmitting system information, etc.

[0085] -SS / PBCH block: An SS / PBCH block may consist of a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks may be transmitted within 5 ms, and each transmitted SS / PBCH block may be distinguished by an index.

[0086] The terminal can detect PSS and SSS and decode PBCH in the initial access phase. The terminal can obtain MIB from PBCH, and can receive control region #0 through MIB. Assuming that the selected SS / PBCH block and the demodulation reference signal (DMRS) sent from control region #0 are quasi-co-located (QCL), the terminal can perform monitoring on control region #0. The terminal can receive system information as downlink control information sent from control region #0. The terminal can obtain random access channel (RACH) related configuration information required for initial access from the received system information. Considering the selected SS / PBCH index, the terminal 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 terminal. It can be seen that the base station selects a block from each SS / PBCH block and monitors the control region #0 corresponding to (or associated with) the SS / PBCH block selected by the terminal.

[0087] Hereinafter, downlink control information (hereinafter referred to as DCI) in the next-generation mobile communication system (5G or NR system) will be described in detail.

[0088] In the next generation mobile communication system (5G or NR system), scheduling information of uplink data (or physical uplink shared channel (PUSCH)) or scheduling information of downlink data (or physical downlink shared channel (PDSCH)) can be sent from the base station to the terminal through DCI. The terminal can monitor the DCI format for fallback and the non-fallback DCI format for PUSCH or PDSCH. The fallback DCI format may be composed of fixed fields predetermined between the base station and the terminal, and the non-fallback DCI format may include configurable fields.

[0089] DCI can be transmitted through a physical downlink control channel (PDCCH) through a channel coding and modulation process. A cyclic redundancy check (CRC) can be attached to the DCI message payload, and the CRC can be scrambled using a radio network temporary identifier (RNTI) corresponding to the identity of the terminal. Depending on the purpose of the DCI message, such as terminal-specific (UE-specific) data transmission, power control commands, or random access responses, different RNTIs can be used to scramble the CRC attached to the payload of the DCI message. That is, the RNTI is not sent explicitly, but can be included in the CRC calculation process and sent. When a DCI message sent on the PDCCH is received, the terminal can use the assigned RNTI to identify the CRC. If the CRC identification result is correct, the terminal can know that the corresponding message has been sent to the terminal.

[0090] For example, the DCI for scheduling PDSCH for system information (SI) can be scrambled with SI-RNTI. The DCI for scheduling PDSCH for random access response (RAR) message can be scrambled with RA-RNTI. The DCI for scheduling PDSCH for paging message can be scrambled with P-RNTI. The DCI for notifying the slot format indicator (SFI) can be scrambled with SFI-RNTI. The DCI for notifying transmit power control (TPC) can be scrambled with TPC-RNTI. The DCI for scheduling PDSCH or PUSCH for a specific terminal can be scrambled with cell RNTI (C-RNTI).

[0091] DCI format 0_0 may be used as a fallback DCI for scheduling PUSCH, and at this time the CRC may be scrambled with the C-RNTI. In one embodiment, the DCI format 0_0 in which the CRC is scrambled by the C-RNTI may include information as shown in the following [Table 3].

[0092] [Table 3]

[0093]

[0094] DCI format 0_1 ​​may be used as a non-fallback DCI for scheduling PUSCH, and the CRC may be scrambled with the C-RNTI. In one embodiment, the DCI format 0_1 ​​in which the CRC is scrambled by the C-RNTI may include information as shown in the following [Table 4].

[0095] [Table 4]

[0096]

[0097]

[0098] DCI format 1_0 may be used as a fallback DCI for scheduling PDSCH, and CRC may be scrambled with C-RNTI. In one embodiment, DCI format 1_0 in which CRC is scrambled by C-RNTI may include information as shown in the following [Table 5].

[0099] [Table 5]

[0100]

[0101]

[0102] DCI format 1_1 may be used as a non-fallback DCI for scheduling PDSCH, where the CRC may be scrambled with the C-RNTI. In one embodiment, DCI format 1_1 where the CRC is scrambled by the C-RNTI may include information as shown in the following [Table 6].

[0103] [Table 6]

[0104]

[0105]

[0106] Figure 4 A diagram showing an example of configuring a control region of a downlink control channel in a next generation mobile communication system according to an embodiment. That is, Figure 4 A view of an embodiment of a control region (control resource set (CORESET)) for transmitting a downlink control channel in a 5G wireless communication system according to one embodiment is shown.

[0107] refer to Figure 4 , Figure 4 An embodiment is shown in which two control regions (control region #1 4-01 and control region #2 4-02) are configured in a time slot 4-20 within a bandwidth portion (UE bandwidth portion) 4-10 of a terminal on a frequency axis and within a time slot 4-20 on a time axis. The control regions 4-01 and 4-02 may be configured as specific frequency resources 4-03 within the entire terminal bandwidth portion 4-10 on a frequency axis. The control regions 4-01 and 4-02 may be configured as one or more OFDM symbols on a time axis, which symbols may be defined as a control resource set duration (4-04). Reference Figure 4 , control region #1 (4-01) can be configured as a control resource set duration of 2 symbols, and control region #2 (4-02) can be configured as a control resource set duration of 1 symbol.

[0108] The control region in the above-mentioned next-generation mobile communication system (5G or NR system) can be configured for the terminal by a base station that performs higher-layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). Configuring the control region for the terminal refers to providing information such as a control region identifier, a frequency position of the control region, and a symbol length of the control region. For example, the configuration of the control region may include the information shown in the following [Table 7].

[0109] [Table 7]

[0110]

[0111] In Table 7, the tci-StatesPDCCH (hereinafter referred to as "TCI state") configuration information may include one or more synchronization signal (SS) / physical broadcast channel (PBCH) indexes or information of a channel state information reference signal (CSI-RS) index having a quasi-co-location (QCL) relationship with a demodulation reference signal (DMRS) transmitted in the corresponding control region. In addition, the tci-StatesPDCCH configuration information may include information on what the QCL relationship is. For example, the configuration of the TCI state may include the information shown in the following [Table 8].

[0112] [Table 8]

[0113]

[0114] Referring to the TCI state configuration, the cell index and / or BWP index of the reference RS and the QCL type can be configured together with the index of the reference RS, i.e., the SS / PBCH block index or the CSI-RS index, in the QCL relationship. The QCL type indicates the channel characteristics assumed to be shared between the reference RS and the control region DMRS, and examples of possible QCL types are as follows.

[0115] -QCL Type A: Doppler shift, Doppler spread, average delay, delay spread.

[0116] -QCL Type B: Doppler shift, Doppler spread.

[0117] -QCL Type C: Doppler shift, average delay.

[0118] -QCL Type D: Spatial Rx parameters.

[0119] For the control region DMRS and other target RSs such as PDSCH DMRS and CSI-RS, the TCI state may be configured similarly, but a detailed description is omitted so as not to obscure the subject of the description.

[0120] Figure 5A view for explaining the structure of a downlink control channel of a next generation mobile communication system according to an embodiment is shown. That is, Figure 5 A diagram showing an example of a basic unit of time and frequency resources for configuring a downlink control channel that may be used in 5G according to one embodiment.

[0121] refer to Figure 5 , the basic unit of time and frequency resources constituting the control channel can be defined as a resource element group (REG) 5-03. REG 5-03 can be defined as 1 OFDM symbol 5-01 on the time axis, 1 physical resource block (PRB) 5-02 on the frequency axis, that is, 12 subcarriers. The base station can configure the downlink control channel allocation unit by connecting REG 5-03.

[0122] like Figure 5 As shown, when the basic unit to which the downlink control channel is allocated in 5G is called a control channel element (CCE) 5-04, one CCE 5-04 may be composed of multiple REGs 5-03. For example, Figure 5 The REG 5-03 shown can be composed of 12 REs. If 1 CCE 5-04 is composed of 6 REGs 5-03, 1 CCE 5-04 can be composed of 72 REs. When configuring the downlink control region, the corresponding region can be composed of multiple CCEs 5-04, and the specific downlink control channel can be mapped to one or more CCEs 5-04 for transmission according to the aggregation level (AL) in the control region. The CCE 5-04 in the control region is divided into numbers, and the numbers of the CCE 5-04 can be allocated according to the logical mapping method.

[0123] Figure 5 The basic unit of the downlink control channel shown, namely, REG 5-03, may include a DCI mapping RE to which the DCI is mapped and an area to which a DMRS 5-05 serving as a reference signal for decoding is mapped. Figure 5 As shown, three DMRS 5-05 can be sent in one REG 5-03. Depending on the aggregation level (AL), the number of CCEs required to send the PDCCH can be 1, 2, 4, 8, 16, and different numbers of CCEs can be used to achieve link adaptation of the downlink control channel. For example, when AL=L, one downlink control channel can be sent through L CCEs.

[0124] The terminal should detect the signal without knowing the downlink control channel information, and a search space indicating a set of CCEs for blind decoding can be defined. A search space is a set of downlink control channel candidates consisting of CCEs that the terminal should attempt to decode at a given aggregation level. Since there are various aggregation levels that constitute bundles of 1, 2, 4, 8, and 16 CCEs, a terminal may have multiple search spaces. A search space set can be defined as a search space set at all configured aggregation levels.

[0125] The search space may be classified into a common search space or a terminal-specific search space. According to one embodiment, a certain group of terminals or all terminals may check the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling of system information or paging messages.

[0126] For example, the terminal can receive PDSCH scheduling allocation information for transmitting SIBs, including the operator information of the cell, by checking the common search space of PDCCH. In the case of the common search space, since a certain group of terminals or all terminals should receive PDCCH, the common search space can be defined as a set of predetermined CCEs. At the same time, the terminal can receive scheduling allocation information for PDSCH or PUSCH of a specific terminal by checking the specific terminal search space of PDCCH. The search space of a specific terminal can be defined for a specific terminal according to the terminal's identity and various system parameters.

[0127] In 5G, the parameters of the search space for PDCCH can be configured from the base station to the terminal through higher layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station can configure the number of PDCCH candidate groups under each aggregation level L, the monitoring period of the search space, the monitoring timing in the symbol unit within the time slot of the search space, the search space type (common search space or search space for a specific terminal), the combination of DCI format and RNTI to be monitored in the search space, the control area index for monitoring the search space, etc. For example, the above configuration may include information such as the following [Table 9].

[0128] [Table 9]

[0129]

[0130] The base station may configure one or more search space sets for the terminal based on the configuration information. According to one embodiment, the base station may configure search space set 1 and search space set 2, configure the terminal to monitor DCI format A scrambled with X-RNTI in search space set 1 in the common search space, and configure the terminal to scramble DCI format B scrambled with Y-RNTI in search space set 2 in the specific terminal search space.

[0131] According to the configuration information, one or more search space sets may exist in a common search space or a specific terminal 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 search spaces for specific terminals.

[0132] In the common search space, the following combinations of DCI formats and RNTIs may be monitored. Of course, this is not limited to the following examples.

[0133] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0134] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0135] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0136] -DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0137] -DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0138] In the specific terminal search space, the following combinations of DCI formats and RNTIs may be monitored. Of course, this is not limited to the following examples.

[0139] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0140] - The RNTI specified by DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI may follow the following definition and usage.

[0141] C-RNTI (Cell RNTI): PDSCH scheduling purpose for a specific terminal.

[0142] TC-RNTI (Temporary Cell RNTI): PDSCH scheduling purpose for a specific terminal.

[0143] CS-RNTI (Configured Scheduling RNTI): a semi-statically configured PDSCH scheduling purpose for a specific terminal.

[0144] RA-RNTI (Random Access RNTI): PDSCH scheduling in the random access phase.

[0145] P-RNTI (Paging RNTI): used for PDSCH scheduling of paging transmission.

[0146] SI-RNTI (System Information RNTI): used for PDSCH scheduling in which system information is transmitted.

[0147] INT-RNTI (Interrupt RNTI): used to notify whether PDSCH is being punctured.

[0148] TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): indicates the purpose of the power control command for PUSCH.

[0149] TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): indicates the purpose of the power control command for PUCCH.

[0150] TPC-SRS-RNTI (Transmit Power Control of SRS RNTI): indicates the purpose of the power control command of SRS.

[0151] In one embodiment, the above DCI format can be defined in the following [Table 10].

[0152] [Table 10]

[0153]

[0154] According to one embodiment, in 5G, multiple search space sets may be configured with different parameters (e.g., the parameters in [Table 9]). Therefore, the set of search space sets monitored by the terminal at each time point may be different. For example, if search space set #1 is configured to an X-time slot period, search space set #2 is configured to a Y-time slot period, and X and Y are different, the terminal may monitor both search space set #1 and search space set #2 in a specific time slot, and monitor one of search space set #1 and search space set #2 in a specific time slot.

[0155] When multiple search space sets are configured for a terminal, the following conditions may be considered to determine the search space set that the terminal should monitor.

[0156] [Condition 1: Limiting the maximum number of PDCCH candidates]

[0157] The number of PDCCH candidates that can be monitored per time slot may not exceed Mμ. Mμ may be defined as the maximum number of PDCCH candidate groups per time slot in a cell configured with a subcarrier spacing of 15·2 μkHz, and may be defined as shown in the following [Table 11].

[0158] [Table 11]

[0159] μ <![CDATA[Maximum number (M μ ) of PDCCH candidates per time slot and per serving cell 0 44 1 36 2 22 3 20

[0160] [Condition 2: Limit the maximum number of CCEs]

[0161] The number of CCEs constituting the entire search space per time slot (here, the entire search space may refer to the entire CCE set corresponding to the joint area of ​​multiple search space sets) may not exceed Cμ. Cμ may be defined as the maximum number of CCEs per time slot in a cell configured with a subcarrier spacing of 15·2μkHz, and may be defined as shown in the following [Table 12].

[0162] [Table 12]

[0163] μ <![CDATA[Maximum number of CCEs per time slot and per serving cell (C μ )]]> 0 56 1 56 2 48 3 32

[0164] For ease of description, a situation where both condition 1 and condition 2 are satisfied at a specific time point may be exemplarily defined as “condition A.” Therefore, failure to satisfy condition A may mean failure to satisfy at least one of the above conditions 1 and 2.

[0165] According to the setting of the search space set of the base station, condition A may not be satisfied at a specific time. If condition A is not satisfied at a specific time, the terminal can select and monitor only a subset of the search space set configured to satisfy condition A at that time, and the base station can send the PDCCH to the selected search space set.

[0166] According to one embodiment, the following method may be followed as a method of selecting some search spaces from a set of all search space sets.

[0167] [Method 1]

[0168] If condition A of PDCCH is not met at a specific time (time slot), the terminal (or base station) may give priority to a search space set configured as a common search space from the search space set existing at the corresponding time point on the search space set configured as a specific terminal search space.

[0169] When all search space sets configured as common search spaces are selected (i.e., when condition A is satisfied even after all search spaces as common search spaces are selected), the terminal (or base station) may select a search space set configured as a search space for a specific terminal. At this time, when there are multiple search space sets configured as search spaces for a specific terminal, a search space set with a lower search space set index may have a higher priority. In consideration of the priority, the terminal or base station may select a search space set for a specific terminal within the range of satisfying condition A.

[0170] The time and frequency resource allocation method for data transmission in NR is described below.

[0171] In NR, in addition to the frequency axis resource candidate allocation indicated by BWP, the following detailed frequency domain resource allocation (FD-RA) can also be provided. Figure 6 A diagram showing an example of PDSCH frequency axis resource allocation in a wireless communication system according to an embodiment.

[0172] Figure 6 A view showing three frequency axis resource allocation methods of Type 0 (6-00), Type 1 (6-05), and Dynamic Switching (6-10) that can be configured by upper layers in NR.

[0173] refer to Figure 6 , if the terminal is configured to use only resource type 0 by upper layer signaling (6-00), some downlink control information (DCI) for allocating PDSCH to the corresponding terminal has a bitmap consisting of NRBG bits. The conditions will be explained again later. At this time, NRBG refers to the number of resource block groups (RBGs) determined according to the BWP size allocated by the BWP indicator and the upper layer parameter RBG-size as shown in [Table 13]. Data is transmitted to the RBG indicated by 1.

[0174] [Table 13]

[0175]

[0176] If the terminal is configured to use only resource type 1 through upper layer signaling 6-05, some DCIs that allocate PDSCH to the corresponding terminal have The frequency axis resource allocation information composed of bits. The conditions will be explained again later. Thus, the base station can configure the starting VRB 6-20 and the length 6-25 of the frequency axis resources continuously allocated therefrom.

[0177] If the terminal is configured to use both resource type 0 and resource type 1 through upper layer signaling (6-10), some DCIs that allocate PDSCH for the corresponding terminal have frequency axis resource allocation information, which consists of a payload 6-15 for configuring resource type 0 and a bit 6-35 of a larger value of a payload 6-20, 6-25 for configuring resource type 1. The conditions will be explained again later. At this time, a bit can be added to the first part (MSB) of the frequency axis resource allocation information in the DCI, and when the corresponding bit is 0, it can indicate the use of resource type 0, and when the corresponding bit is 1, it can indicate the use of resource type 1.

[0178] The following describes a time domain resource allocation method for a data channel in a next-generation mobile communication system (5G or NR system).

[0179] The base station may configure a table of time domain resource allocation information of a downlink data channel (physical downlink shared channel (PDSCH)) and an uplink data channel (PUSCH) for the terminal as higher layer signaling (e.g., RRC signaling). A table consisting of a maximum maxNrofDL-Allocations = 16 entries may be configured for PDSCH, and a table consisting of a maximum maxNrofDL-Allocations = 16 entries may be configured for PUSCH. In one 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 when the PDCCH is received and the time when the PDSCH scheduled by the received PDCCH is sent, denoted as K0), PDCCH-to-PUSCH slot timing (corresponding to the time interval in time slots between the time when the PDCCH is received and the time when the received PDCCH scheduling the PUSCH is sent, denoted as K2), information about the position and length of the starting symbol for scheduling PDSCH or PUSCH in the time slot, mapping type of PDSCH or PUSCH, etc. For example, information such as the following [Table 14] or [Table 15] may be notified from the base station to the terminal.

[0180] [Table 14]

[0181]

[0182] [Table 15]

[0183]

[0184] The base station may notify the terminal of one of the entries in the table of the above time domain resource allocation information through L1 signaling (e.g., DCI) (e.g., indicated by the "time domain resource allocation" field in the DCI). The terminal may obtain the time domain resource allocation information for PDSCH or PUSCH based on the DCI received from the base station.

[0185] Figure 7 A diagram showing an example of time domain resource allocation for NR.

[0186] refer to Figure 7 The base station can indicate the subcarrier spacing (SCS) (μ) of the data channel and the control channel according to the starting position (7-00) and length (7-05) of the OFDM symbol in a time slot dynamically indicated by the DCI. PDSCH , μ PDCCH ), the subcarrier spacing (SCS) (μ PDSCH , μ PDCCH ) is configured using the upper layer, the scheduling offset (K0) value and the time axis position of the PDSCH resources.

[0187] Figure 8 A diagram showing an example of time axis resource allocation according to subcarrier spacings of a data channel and a control channel in a wireless communication system according to an embodiment is shown.

[0188] refer to Figure 8 , it can be seen that when the subcarrier spacing of the data channel and the control channel is the same (8-00, μ PDSCH =μ PDCCH ), the number of time slots for data and control is the same, so that the base station and the terminal are scheduled to shift according to the predetermined time slot shift K0. On the other hand, it can be seen that when the subcarrier spacing of the data channel and the control channel is different (8-05, μ PDSCH ≠μ PDCCH ), the number of time slots for data and control is different, so that the base station and the terminal are scheduled offset according to the predetermined time slot offset K0 based on the subcarrier spacing of the PDCCH.

[0189] In LTE and NR, the terminal has a process of reporting the capabilities supported by the terminal to the corresponding base station when connected to the serving base station. In the following description, this is referred to as terminal capability (report). The base station can send a terminal capability query message requesting a capability report to the terminal in a connected state. In this message, the base station can include a request for the terminal capability of each RAT type. The request for each RAT type can include the requested frequency band information. In addition, the terminal capability query message can request multiple RAT types from one RRC message container, or the terminal capability query message including a request for each RAT type can be delivered to the terminal multiple times. That is, the terminal capability query is repeated multiple times, and the terminal can report the number of times by configuring the corresponding terminal capability information message. In the next generation mobile communication system, a terminal capability request for MR-DC (including NR, LTE and E-UTRA new wireless dual connection (EN-DC)) may be made. For reference, the terminal capability query message generally starts to be sent after the terminal is connected, but it can also be requested in any case when the base station is needed.

[0190] In this step, the terminal that receives the terminal capability report request from the base station can configure the terminal capability according to the RAT type and frequency band information requested from the base station. In the NR system, the method for configuring the terminal capability in the terminal is summarized as follows.

[0191] 1. If the terminal is provided with a list of LTE and / or NR bands at the terminal capability request from the base station, the terminal can configure a band combination (BC) for EN-DC and NR standalone (SA). That is, a candidate list of BCs for EN-DC and NR SA can be configured based on the bands requested from the base station by the band list (FreqBandList). In addition, the priority of the band has a priority in the order described in the band list.

[0192] 2. If the base station requests the terminal capability report by configuring the "eutra-nr-only" flag or the "eutra" flag, the terminal can completely remove the NR SA BC from the configured BC candidate list. This operation can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0193] 3. After that, the terminal can remove the fallback BC from the candidate list of BCs configured in the above steps. Here, the fallback BC corresponds to the case where the frequency band corresponding to at least one SCell is removed from the superset BC, and can be omitted because the superset BC may have covered the fallback BC. This step is also applicable to multi-RAT dual connectivity (MR-DC), that is, LTE bands can also be applied. The remaining BC after this stage is the final "candidate BC list".

[0194] 4. The terminal can select the BC to be reported by selecting the BC corresponding to the requested RAT type in the final "candidate BC list". In this step, the terminal can configure the supported band combination list (supportedBandCombinationList) in a predetermined order. That is, the terminal can configure the BC and terminal capabilities to be reported in a predetermined order of rat-type. (nr->eutra-nr->eutra). In addition, the feature set combination (featureSetCombination) of the configured supported band combination list can be configured, and a list of "candidate feature set combinations" can be constructed from the candidate BC list, where the list for fallback BC (including the same or lower level capabilities) is removed. The "candidate feature set combination" includes two feature set combinations of NR and EUTRA-NR BCs, and can be obtained from the feature set combinations of UE-NR-capability and UE-MRDC-capability containers.

[0195] 5. In addition, if the requested rat type is eutra-nr and affects it, the feature set combination can be included in two containers, namely UE-MRDC-capability and UE-NR-capability. However, the feature set of NR can only include UE-NR-capability.

[0196] After configuring the terminal capabilities, the terminal can send a terminal capability information message including the terminal capabilities to the base station. The base station can then perform appropriate scheduling and transmission / reception management for the corresponding terminal based on the terminal capabilities received from the terminal.

[0197] In NR, the base station may have a CSI framework for instructing the terminal to measure and report channel state information (CSI). The CSI framework of NR may consist of at least two elements: resource settings and report settings, and the report settings may have an association relationship with each other by referencing at least one ID of the resource settings.

[0198] According to one embodiment, the resource setting may include information related to a reference signal (RS) used by the terminal to measure channel state information. The base station may configure at least one resource setting for the terminal. As an example, the base station and the terminal may exchange signaling information as shown in [Table 16] to send information about the resource setting.

[0199] [Table 16]

[0200]

[0201] In Table 16, the signaling information CSI-resource configuration (CSI-ResourceConfig) includes information about each resource setting. According to the signaling information, each resource setting may include a resource setting index (csi-resource configuration Id (csi-ResourceConfigId)) or a BWP index (bwp-ID), a timeline transmission configuration of the resource (resource type), or a resource set list (csi-RS-resource set list (csi-RS-ResourceSetList)) including at least one resource set (resource set). The timeline transmission configuration of the resource can be configured as non-periodic transmission, semi-persistent transmission, or periodic transmission. The resource set list can be a set including resource sets for channel measurement, or a set including resource sets for interference measurement. When the resource set list is a set including resource sets for channel measurement, each resource set may include at least one resource, which may be an index of a CSI reference signal (CSI-RS) resource or a synchronization / broadcast channel block (SS / PBCH block (SSB)). When the resource set list is a set including resource sets for interference measurement, each resource set may include at least one interference measurement resource (CSI interference measurement (CSI-IM)).

[0202] For example, when a resource set includes a CSI-RS, the base station and the terminal may exchange signaling information as shown in [Table 17] in order to transmit information about the resource set.

[0203] [Table 17]

[0204]

[0205] In Table 17, signaling information NZP-CSI-RS-Resource Set (NZP-CSI-RS-ResourceSet) includes information about each resource set. According to the signaling information, each resource set may include information about at least a resource set index (nzp-CSI-resource set Id (nzp-CSI-ResourceSetId)) or an index set of included CSI-RS (nzp-CSI-RS-resources (nzp-CSI-RS-Resources)), and may include information about a spatial transmission filter of the included CSI-RS resources or whether to use tracking (trs-Info) of the included CSI-RS resources (repeated) part.

[0206] The CSI-RS may be the most representative reference signal included in the resource set. The base station and the terminal may transmit and receive signaling information as shown in [Table 18] to transmit information about the CSI-RS resource.

[0207] [Table 18]

[0208]

[0209] In [Table 18], signaling information NZP-CSI-RS-Resource includes information about each CSI-RS. The information included in the signaling information NZP-CSI-RS-Resource may have the following meanings.

[0210] -nzp-CSI-RS-ResourceId: CSI-RS resource index

[0211] - Resource Mapping: Resource mapping information of CSI-RS resources

[0212] - Power Control Offset (powerControlOffset): The ratio between PDSCH EPRE (energy per RE) and CSI-RS EPRE

[0213] -Power Control Offset SS (powerControlOffsetSS): Ratio between SS / PBCH block EPRE and CSI-RS EPRE

[0214] -Scrambling ID: Scrambling index of the CSI-RS sequence

[0215] -PeriodicityAndOffset: The transmission period and time slot offset of CSI-RS resources

[0216] -qcl-InfoPeriodicCSI-RS: TCI-state information when the corresponding CSI-RS is periodic CSI-RS

[0217] The resource mapping (resourceMapping) included in the signaling information NZP-CSI-RS-Resource (NZP-CSI-RS-Resource) represents the resource mapping information of the CSI-RS resource, and may include frequency resource element (RE) mapping, port number, symbol mapping, CDM type, frequency resource density, and band mapping information. The number of ports, frequency resource density, CDM type, and time-frequency axis RE mapping that can be configured by this may have a value determined in one of the rows of [Table 19].

[0218] [Table 19]

[0219]

[0220] [Table 19] Frequency resource density, CDM type, frequency axis and time axis starting position of CSI-RS component RE pattern The number of frequency-axis REs (k') and time-axis REs (l') of the CSI-RS component RE pattern that can be configured according to the number of CSI-RS ports (X). The aforementioned CSI-RS component RE pattern can be a basic unit constituting a CSI-RS resource. The CSI-RS component RE pattern can be composed of YZ REs through Y=1+max(k') REs on the frequency axis and Z=1+max(l') REs on the time axis. When the number of CSI-RS ports is 1 port, the CSI-RS RE position can be specified without limiting the subcarriers in the physical resource block (PRB), and the CSI-RS RE position can be specified by a 12-bit bitmap. When the number of CSI-RS ports is {2, 4, 8, 12, 16, 24, 32} ports and Y=2, the CSI-RS RE position can be specified for every two subcarriers in the PRB, and the CSI-RSRE position can be specified by a 6-bit bitmap. When the number of CSI-RS ports is 4 ports and Y=4, the CSI-RS RE position can be specified for every four subcarriers in the PRB, and the CSI-RS RE position can be specified by a 3-bit bitmap. Similarly, the time axis RE position can be specified by a total of 14 bits of bitmap. At this time, according to the Z value in [Table 19], the length of the bitmap can be changed as in the frequency position specification. However, since the principle is similar to the above description, the redundant description will be omitted below.

[0221] According to one embodiment, the report settings may be associated with each other by referring to at least one ID of the resource setting, and the resource setting associated with the report setting provides configuration information including information about a reference signal for measuring channel information. When the channel information is measured using the resource setting associated with the report setting, the channel information may be reported using the measured channel information according to the reporting method set in the report setting associated with the channel setting.

[0222] According to one embodiment, the report setting may include configuration information related to the CSI reporting method. For example, the base station and the terminal may exchange signaling information as shown in [Table 20] to send information about the report setting.

[0223] [Table 20]

[0224]

[0225]

[0226] In [Table 20], the signaling information CSI-ReportConfig includes information about each report setting. The information included in the signaling information CSI-ReportConfig may have the following meanings.

[0227] - Report Configuration Id (reportConfigId): may indicate a report setting index.

[0228] -Carrier: can indicate the serving cell index.

[0229] - Resources for channel measurement (resourcesForChannelMeasurement): may indicate a resource setting index for channel measurement related to a report setting.

[0230] -csi-IM-ResourcesForInterference: may indicate a resource setting index having CSI-IM resources for interference measurement associated with a reporting setting.

[0231] -nzp-CSI-RS-ResourcesForInterference: may indicate a resource setting index of CSI-RS resources with interference measurement related to the reporting setting.

[0232] - Report Configuration Type (reportConfigType): indicates the timeline transmission setting and transmission channel of the channel report, and can have aperiodic transmission or semi-persistent physical uplink control channel (PUCCH) transmission or semi-periodic PUSCH transmission or periodic transmission configuration.

[0233] -Report Quantity (reportQuantity): indicates the type of channel information to be reported, and may have one type of channel information when a channel report is not sent ("None") and one type of channel information when a channel report is sent ("cri-RI-PMI-CQI", "cri-RI-i1", "cri-RI-i1-CQI", "cri-RI-CQI", "cri-RSRP", "ssb-Index-RSRP", "cri-RI-LI-PMI-CQI"). Here, the elements included in the channel information type mean a channel quality indicator (CQI), a precoding metric indicator (PMI), a CSI-RS resource indicator (CRI), a SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI) and / or an L1 reference signal received power (RSRP).

[0234] - Report frequency configuration (reportFreqConfiguration): indicates whether the channel information to be reported includes only information of the entire frequency band or information about each sub-frequency band, and when information of each sub-frequency band is included, there may be configuration information of the sub-frequency band including the channel information.

[0235] - Time restriction for channel measurement (timeRestrictionForChannelMeasurements): In the reference signal referenced by the reported channel information, it can be indicated whether the reference signal used for channel measurement is restricted in the time axis.

[0236] -Time restriction for interference measurement (timeRestrictionForInterferenceMeasurements): In the reference signal referenced by the channel information to be reported, it can be indicated whether the reference signal used for interference measurement is restricted in the time axis.

[0237] -Codebook configuration (codebookConfig): can indicate the codebook information to which the channel information to be reported refers.

[0238] -Group-based beam reporting (codebookConfig): can indicate whether to group channel reports by beam.

[0239] -cqi-Table: may indicate the CQI table index referenced by the channel information to be reported.

[0240] -Subband Size (subbandSize): may indicate an index of a subband size used to indicate channel information.

[0241] - Non-PMI-Port Indication: port mapping information referred to when reporting non-PMI channel information may be indicated.

[0242] When the base station instructs reporting of channel information through higher layer signaling or L1 signaling, the terminal can perform channel information reporting by referring to setting information included in the indicated report setting.

[0243] The base station may instruct the terminal to report channel state information (CSI) through radio resource control (RRC) signaling or higher layer signaling including medium access control (MAC) control element (CE) signaling or L1 signaling (eg, common DCI, group common DCI, terminal-specific DCI).

[0244] For example, the base station may use DCI format 0_1 ​​to indicate the terminal to report non-periodic channel information (CSI report) through higher layer signaling or DCI. The base station may configure multiple CSI report triggering states through higher layer signaling, including parameters for non-periodic CSI reporting of the terminal or parameters for CSI reporting. The parameters of the CSI report or the parameters of the CSI report triggering state are the PDCCH including the DCI and the physical uplink control channel (PUCCH) including the CSI report, or the time slot interval or possible time slot interval set between the PUSCH, the reference signal ID, the type of channel information to be included, etc. When the base station indicates some of the multiple CSI report triggering states to the terminal through DCI, the terminal reports the channel information according to the CSI report setting of the report setting configured in the indicated CSI report triggering state. The time axis resource allocation of the PUCCH or PUSCH including the CSI report of the terminal can be indicated by the time slot interval of the PDCCH indicated by the DCI, the starting symbol and symbol length indication in the time slot of the time axis resource allocation of the PUSCH, or part or all of the PUCCH resource indication. For example, the position of the time slot through which the PUSCH including the CSI report of the terminal is transmitted can be indicated by the time slot interval with the PDCCH indicated by the DCI, and the starting symbol and symbol length in the time slot can be indicated by the time domain resource allocation field of the above DCI.

[0245] For example, the base station may indicate semi-persistent CSI reporting to the terminal through higher layer signaling or DCI using DCI format 0_1. The base station may activate or deactivate semi-persistent CSI reporting through DCI scrambled with SP-CSI-RNTI or higher layer signaling (including MAC CE signaling). When semi-persistent CSI reporting is activated, the terminal may periodically report channel information according to the configured time slot interval. When semi-persistent CSI reporting is deactivated, the terminal may stop reporting activated periodic channel information. The base station configures multiple CSI report triggering states, including parameters for semi-persistent CSI reporting or parameters for semi-persistent CSI reporting through higher layer signaling. The parameters for CSI reporting or the parameters for CSI reporting triggering states may include a time slot spacing between a PDCCH having a DCI indicating a CSI report and a PUCCH or PUSCH having a CSI report, or a set of possible time slot spacings, a time slot interval between a time slot in which higher layer signaling indicating a CSI report is activated and a PUCCH or PUSCH including a CSI report, a time slot spacing period of CSI reporting, a type of included channel information, etc. When the base station activates some of a plurality of CSI reporting triggering states or some of a plurality of reporting settings to the terminal through higher layer signaling or DCI, the terminal may report channel information according to the reporting setting included in the indicated CSI reporting triggering state or the CSI reporting setting configured in the activated reporting setting. The time axis resource allocation of the PUCCH or PUSCH including the CSI report of the terminal can be indicated by the following: part or all of the time slot interval period of the CSI report, the time slot interval with the time slot in which the upper layer signaling is activated, or the time slot interval with the PDCCH indicated by the DCI, the starting symbol and symbol length indication in the time slot for resource allocation on the time axis of the PUSCH, and the PUCCH resource indication. For example, the position of the time slot for sending the PUSCH including the CSI report of the terminal can be indicated by the time slot interval with the PDCCH indicated by the DCI, and the starting symbol and symbol length in the time slot can be indicated by the time domain resource allocation field of the above-mentioned DCI format 0_1. For example, the position of the time slot for sending the PUSCH including the CSI report of the terminal can be indicated by the time slot interval period of the CSI report configured by higher layer signaling, the time slot interval between the time slot in which the higher layer signaling is activated and the PUCCH including the CSI report, and the starting symbol and symbol length in the time slot can be indicated by the starting symbol and symbol length of the PUCCH resources configured by higher layer signaling.

[0246] For example, the base station may indicate periodic CSI reporting to the terminal through higher layer signaling. The base station may activate or deactivate periodic CSI reporting through higher layer signaling including RRC signaling. When periodic CSI reporting is activated, the terminal may periodically report channel information according to the configured time slot interval. When periodic CSI reporting is deactivated, the terminal may stop reporting activated periodic channel information. The base station may configure report settings including parameters for periodic CSI reporting of the terminal through higher layer signaling. The parameters of the CSI report may include the time slot interval between the PUCCH or PUSCH with the CSI report and the time slot in which the higher layer signaling indicates activation of the CSI report, the time slot interval period of the CSI report, the reference signal ID used to measure the channel state, the type of channel information, etc. The time axis resource allocation of the PUCCH or PUSCH including the CSI report of the terminal can be indicated by: part or all of the time slot interval period of the CSI report, the time slot interval with the time slot in which the upper layer signaling is activated, or the time slot interval with the PDCCH indicated by the DCI, the starting symbol and symbol length indication in the time slot for resource allocation on the time axis of the PUSCH, and the PUCCH resource indication. For example, the position of the time slot for sending the PUSCH including the CSI report of the terminal can be indicated by the time slot interval period of the CSI report configured via higher layer signaling, the time slot interval between the time slot in which the higher layer signaling is activated and the PUCCH including the CSI report, and the starting symbol and symbol length in the time slot can be indicated by the starting symbol and symbol length of the PUCCH resource configured via higher layer signaling.

[0247] When the base station instructs the terminal to perform non-periodic CSI reporting or semi-persistent CSI reporting through DCI, the terminal can determine whether to perform valid channel reporting through the indicated CSI report in consideration of the channel calculation time required for the CSI report. For non-periodic CSI reporting or semi-persistent CSI reporting indicated by DCI, the terminal can perform valid CSI reporting starting from the uplink symbol after Z symbols after the last symbol included in the PDCCH, the PDCCH including the DCI indicating the CSI report, and the Z symbol described above can be changed according to the parameter set of the downlink bandwidth part corresponding to the PDCCH including the DCI indicating the CSI report, the parameter set of the uplink bandwidth part corresponding to the PUSCH sending the CSI report, and the type or characteristics of the channel information reported in the CSI report (number of reports, frequency band granularity, number of reference signals, codebook type, etc.). In other words, in order to determine which CSI report is a valid CSI report (if the CSI report is a valid CSI report), the uplink transmission of the corresponding CSI report should not be performed before the Zref symbol including the timing advance. At this time, Zref symbol is the time T from the moment when the last symbol of triggering PDCCH ends. proc，CSI =(Z)(2048+144)·κ2 -μ ·T C The uplink symbol after the cyclic prefix (CP) starts. Here, the detailed value of Z follows the following description, T c =1 / (Δf max ·N f ), Δf max =480·10 3 Hz、N f =4096, κ=64 and μ are parameter sets. At this time, μ can be committed to use in (μ PDCCH , μ CSI-RS , μ UL ) causes the maximum value T proc，CSI The one, μ PDCCH It can represent the subcarrier spacing used for PDCCH transmission, μ CSI-RS may represent the subcarrier spacing used for CSI-RS transmission, and μ UL M may represent the subcarrier spacing of an uplink channel used for uplink control information (UCI) transmission for CSI reporting. As another example, μ may commit to use resulting in (μ PDCCH , μ UL ) has the maximum value T proc，CSI The one. PDCCH and μ UL For the definition of , refer to the above description. For the convenience of later explanation, satisfying the above conditions is referred to as satisfying CSI report validity condition 1.

[0248] In addition, when the reference signal for measuring the channel of the non-periodic CSI report indicated to the terminal through the DCI is a non-periodic reference signal, a valid CSI report can be performed starting from the uplink symbol after Z' symbols after the end of the last symbol including the reference signal, and the above Z' symbol can vary according to the following: the parameter set of the downlink bandwidth part corresponding to the PDCCH including the DCI indicating the CSI report, the parameter set of the bandwidth corresponding to the reference signal for channel measurement of the CSI report, the parameter set of the uplink bandwidth part corresponding to the PUSCH for sending the CSI report, and the type or characteristics of the channel information reported in the CSI report (number of reports, frequency band granularity, reference signal port number, codebook type, etc.). In other words, in order to determine which CSI report is a valid CSI report (if the CSI report is a valid CSI report), the uplink transmission of the corresponding CSI report should not be performed before the Zref symbol including the timing advance. At this time, the Zref' symbol is the moment after the last symbol of the non-periodic CSI-RS or non-periodic CSI-IM triggered by the triggering PDCCH ends after a time T' proc，CSI =(Z′)(2048+144)·κ2 -μ ·T C The uplink symbol after the cyclic prefix (CP) starts. Here, the detailed value of Z' follows the following description, T c =1 / (Δf max ·N f ), Δf max =480·10 3 Hz、N f =4096, κ=64 and μ are parameter sets. At this time, μ can be committed to use in (μ PDCCH , μ CSI-RS , μ UL ) causes the maximum value T proc，CSI The one, μ PDCCH It can represent the subcarrier spacing used to trigger PDCCH transmission, μ CSI-RS may represent the subcarrier spacing used for CSI-RS transmission, and μ UL M may represent the subcarrier spacing of an uplink channel used for uplink control information (UCI) transmission for CSI reporting. As another example, μ may commit to use resulting in (μ PDCCH , μ UL ) in the maximum value T proc，CSI At this time, μ PDCCH and μ UL For the definition of , refer to the above description. For the convenience of later explanation, satisfying the above condition is referred to as satisfying CSI report validity condition 2.

[0249] If the base station indicates the aperiodic CSI report of the aperiodic reference signal to the terminal through the DCI, the terminal can perform a valid CSI report from the first uplink, which symbol satisfies both the time since the last symbol included in the PDCCH including the DCI indicating the CSI report and the time after the last symbol including the reference signal. After the end of the Z' symbol. That is, in the case of aperiodic CSI report based on the aperiodic reference signal, when both CSI report validity conditions 1 and 2 are met, it is determined to be a valid CSI report.

[0250] If the CSI reporting time point indicated by the base station does not meet the CSI calculation time requirement, the terminal may determine that the corresponding CSI report is invalid and may not consider updating the channel information state of the CSI report.

[0251] The Z and Z' symbols used to calculate the above CSI calculation time follow the following [Table 21] and [Table 22]. For example, when the channel information reported in the CSI report includes only wideband information, the number of reference signal ports is 4 or less, the reference signal resource is one, the codebook type is "type I-Single Panel", or the type of channel information reported (report number) is "cri-RI-CQI", the Z and Z' symbols follow the value Z in [Table 22] 1 , Z′ 1 In the future, this will be referred to as delay requirement 2. In addition, when the PUSCH including the CSI report does not include TB or HARQ-ACK and the CPU occupancy of the terminal is 0, the Z and Z' symbols follow the value Z in [Table 21] 1 , Z′ 1 , and this is called delay requirement 1. The above description of CPU occupancy has been described in detail below. In addition, when the reporting quantity is "cri-RSRP" or "ssb-Index-RSRP", the symbols Z and Z' follow the value Z in [Table 22] 3 , Z′ 3 X1, X2, X3, and X4 in Table 22 refer to the terminal capabilities at the beam reporting time, and KB1 and KB2 in Table 22 refer to the terminal capabilities at the beam change time. If it does not correspond to the type or characteristics of the channel information reported in the above CSI report, the Z and Z' symbols follow the value Z in [Table 22] 2 , Z′ 2 .

[0252] [Table 21]

[0253]

[0254] [Table 22]

[0255]

[0256] When the base station instructs the terminal to perform aperiodic / semi-persistent / periodic CSI reporting, the CSI reference resource can be configured in time slot units to determine the reference time of the reference signal used to measure the channel information reported in the CSI report. For example, when it is indicated that CSI report #X is sent in uplink time slot n', the CSI reference resource of CSI report #X sent in uplink time slot n' can be defined as downlink time slot n-nCSI-ref. The downlink time slot n is calculated by considering the downlink and uplink pneumatic neurons μDL and μUL as When the CSI report #0 sent in uplink slot n' is a semi-persistent or periodic CSI report, the slot interval nCSI-ref between downlink slot n and the CSI reference resource follows And when multiple CSI-RS resources are connected to the corresponding CSI report according to the number of CSI-RS resources measured using the dry channel, follow When the CSI report #0 transmitted in the uplink time slot n′ is an aperiodic CSI report, the CSI calculation time Z′ for channel measurement is considered and calculated as above is the number of symbols included in a time slot, which is assumed to be

[0257] When the base station instructs the terminal to send a certain CSI report in uplink time slot n' through higher layer signaling or DCI, the terminal can report CSI by performing channel measurement or interference measurement on the CSI-RS resource or CSI-IM resource or SSB resource sent in the CSI reference resource time slot no later than the CSI report, which is sent in the uplink time slot n' in the CSI-RS resource or CSI-IM or SSB resource associated with the corresponding CSI report. The CSI-RS resource, CSI-IM resource, SSB resource associated with the corresponding CSI report may refer to: a CSI-RS resource, CSI-IM resource, SSB resource included in a resource set configured in a resource setting referenced by a report setting of a CSI report of the terminal configured by higher layer signaling; a CSI-RS resource, CSI-IM resource, SSB resource referenced by a CSI report trigger state including parameters for the corresponding CSI report; a CSI-RS resource, CSI-IM resource or SSB resource indicated by an ID of a reference signal (RS) set.

[0258] The CSI-RS / CSI-IM / SSB timing in the embodiment refers to the transmission time point of the CSI-RS / CSI-IM / SSB resource determined by the combination of DCI triggering and higher layer configuration or higher layer configuration. For example, a semi-persistent or periodic CSI-RS resource is determined according to a slot period and a slot offset configured as higher layer signaling, and the transmission symbol in the slot is determined by one of the resource mapping methods in the slot according to the resource mapping information (resourceMapping) reference [Table 19]. For another example, in a non-periodic CSI-RS resource, the slot to be transmitted is determined according to the slot offset of the PDCCH including the DCI indicating the channel report configured as higher layer signaling, and the transmission symbol in the slot is determined by one of the resource mapping methods in the slot according to the resource mapping information (resourceMapping) reference [Table 19].

[0259] The above CSI-RS timing can be determined by considering the transmission time of each CSI-RS resource independently or comprehensively considering the transmission time of one or more CSI-RS resources included in the resource set. Therefore, according to each resource set configuration, for the CSI-RS timing, the following two interpretations are possible.

[0260] - Interpretation 0-1-1: From the start time of transmitting the earliest symbol to the end time of the latest symbol of one specific resource, among one or more CSI-RS resources included in the resource set configured in the resource setting referenced by the report setting configured for CSI reporting.

[0261] - Interpretation 0-1-2: Among all CSI-RS resources included in the resource set configured in the resource setting referenced by the report setting configured for CSI reporting, from the start time of the earliest symbol to which the CSI-RS resource transmitted at the earliest time is transmitted to the end time of the latest symbol to which the CSI-RS resource transmitted at the earliest time is transmitted.

[0262] In the following, in an embodiment, two interpretations of CSI-RS timing may be considered for separate application. In addition, two interpretations of CSI-IM timing and SSB timing may be considered, such as CSI-RS timing, but the principle is similar to the above description, so repeated description will be omitted below.

[0263] In an embodiment, "CSI-RS / CSI-IM / SSB timing for CSI report #X sent from uplink time slot n'" refers to: a set of CSI-RS timing, CSI-IM timing, SSB timing of CSI reference resources no later than CSI-RS resources, CSI-IM resources for CSI report #X sent from uplink time slot n'; including CSI-RS timing, CSI-IM timing, SSB timing of SSB resources in the resource set configured in the resource setting referenced by the report setting configured for CSI report #X.

[0264] In an embodiment, for "the latest CSI-RS / CSI-IM / SSB opportunity for CSI report #X sent in uplink slot n'", the following two interpretations are possible.

[0265] - Interpretation 0-2-1: The latest CSI-RS opportunity of CSI report #X sent in uplink slot n' and the latest CSI-RS opportunity, the latest CSI-IM opportunity of CSI report #X sent in uplink slot n' and the latest CSI-IM opportunity, and the set of opportunities including the latest SSB opportunity among the SSB opportunities of CSI report #0 sent in uplink slot n'

[0266] - Interpretation 0-2-2: CSI-RS timing, CSI-IM timing, SSB timing for CSI report #X transmitted in uplink slot n'

[0267] Hereinafter, in an embodiment, two interpretations of the latest CSI-RS / CSI-IM / SSB timing for CSI report #X sent from uplink slot n' may be applied separately, which is the latest CSI-RS / CSI-IM / SSB timing. In addition, when considering the above two interpretations (interpretation 0-1-1, interpretation 0-1-2) for CSI-RS timing, CSI-IM timing and SSB timing, in an embodiment, considering all four different interpretations (applying interpretation 0-1-1 and interpretation 0-2-1, applying interpretation 0-1-1 and interpretation 0-2-2, applying interpretation 0-1-2 and interpretation 0-2-1, and applying interpretation 0-1-2 and interpretation 0-2-2), "the last CSI-RS / CSI-IM / SSB timing for CSI report #X sent in uplink slot n'" may be applied separately.

[0268] The base station may indicate the CSI report by considering the amount of channel information that the terminal can calculate for the CSI report at the same time, that is, the number of channel information calculation units (CSI) of the terminal. If the number of channel information calculation units that the terminal can calculate at the same time is N CPU, then the terminal may not expect to need more than N CPU The CSI report indication of the base station based on the channel information calculation may not be considered to update more than N CPU The channel information calculated by the channel information N CPU The terminal may report it to the base station through higher layer signaling, or the base station may configure it through higher layer signaling.

[0269] Assume that the CSI report indicated by the base station to the terminal occupies the total number of channel information that the terminal can calculate simultaneously N CPU For each CSI report n (n=0, 1, ..., N-1), for example, if the number of channel information calculation units required for the CSI report is Then the number of channel information calculation units required for a total of N CSI reports can be called The channel information calculation unit required for each report quantity (reportQuantity) configured in the CSI report can be configured as shown in [Table 23].

[0270] [Table 23]

[0271]

[0272] If the number of channel information calculations required by the terminal for multiple CSI reports at a certain time is greater than the number N of channel information calculation units that the terminal can calculate simultaneously CPU , the terminal may not consider updating the channel information of some CSI reports. Among the multiple indicated CSI reports, the CSI reports that do not consider the update of the channel information are determined by considering at least the time when the calculation of the channel information required for the CSI report occupies the CPU and the priority of the reported channel information. For example, the calculation of the channel information required for the CSI report may not consider the update of the channel information of the CSI report that starts at the time when the CPU occupies the most time, and may not consider giving priority to updating the channel information for the CSI report with a lower priority of the channel information.

[0273] The priority of channel information can be determined by referring to the following [Table 24].

[0274] [Table 24]

[0275]

[0276] The CSI priority of the CSI report is determined by the priority value PriiCSI(y, k, c, s) in [Table 24]. Referring to [Table 24], the CSI priority value is determined by the type of channel information included in the CSI report, the timeline reporting characteristics of the CSI report (non-periodic, semi-persistent, periodic), the channel through which the CSI report is sent (PUSCH, PUCCH), the serving cell index, and the CSI report setting index. The CSI priority of the CSI report is compared with the priority value PriiCSI(y, k, c, s), and it is determined that the CSI priority of the CSI report with a lower priority value is higher.

[0277] If the time when the calculation of the channel information required for the CSI report of the terminal indicated by the base station occupies the CPU is the CPU occupancy time, the CPU occupancy time is determined by considering some or all types of channel information included in the CSI report, the time axis characteristics of the CSI report (non-periodic, semi-persistent, periodic), the higher layer signaling indicating the CSI report or the time slot or symbol occupied by the DCI, and the time slot or symbol occupied by the reference signal used to measure the channel condition.

[0278] Fig. 9 A diagram showing an example of CPU occupancy time for a CSI report where the number of reports included in the CSI report is not configured as “None” according to some embodiments.

[0279] Fig. 9 9-00 shows a diagram of the CPU occupancy time of a non-periodic CSI report in which the number of reports included in the CSI report is not configured as "none" according to some embodiments. When the base station indicates that a non-periodic CSI report #X is sent in uplink slot n' through DCI using DCI format 0_1, the CPU occupancy time (9-05) of the CSI report #X sent in uplink slot n' can be defined from the next symbol of the last symbol occupied by the PDCCH (9-10) including the DCI indicating the non-periodic CSI report #X to the last symbol occupied by the PUSCH 9-15 including the CSI report #X sent in the link slot n'.

[0280] Fig. 99-20 shows a view of the CPU occupancy time of a periodic or semi-persistent CSI report in which the number of reports included in the CSI report is not configured as "none" according to some embodiments. When the base station sends a periodic or semi-persistent CSI report #X in uplink slot n' through a DCI indication using DCI format 0_1 ​​scrambled with higher layer signaling or SP-CSI-RNTI, the CPU occupancy time (9-25) of the CSI report #X sent in uplink slot n' can be defined from the first symbol of the first transmitted CSI-RS / CSI-IM / SSB resource corresponding to the latest CSI-RS / CSI-IM / SSB opportunity (9-30) in the CSI-RS / CSI-IM / SSB opportunity for the CSI report #X sent in the uplink slot n' to the last symbol occupied by the PUCCH or PUSCH (9-35) included in the CSI report #X sent in the uplink slot n'. The latest CSI-RS / CSI-IM / SSB opportunity (9-30) may not be located after the CSI reference resource (9-40) of CSI report #X. Exceptionally, when the base station indicates a semi-persistent CSI report through DCI and the terminal performs the first CSI report of the semi-persistent CSI report #X, the CPU occupancy time of the first CSI report can be defined from the next symbol of the last symbol occupied by the PDCCH including the DCI indicating the semi-persistent CSI report #X to the last symbol occupied by the PUSCH including the first CSI report. In this way, the causal relationship of the terminal's operation on the timeline can be guaranteed by taking into account the time point of indicating the CSI report and the time point when the CPU occupancy time starts.

[0281] For example, the rules shown in Table 25 below may be followed.

[0282] [Table 25]

[0283]

[0284]

[0285] Fig.10 A diagram showing an example of CPU occupancy time for a CSI report where the number of reports included in the CSI report is configured as "None" according to some embodiments.

[0286] Fig.1010-00 shows a view of the CPU occupancy time of the non-periodic CSI report according to some embodiments, including that the number of reports in the CSI report is configured as "none". When the base station sends the non-periodic CSI report #X in the uplink time slot n' through the DCI indication using the DCI format 0_1, the CPU occupancy time (10-05) of the CSI report #X sent in the uplink time slot n' can be defined from the next symbol of the last symbol occupied by the PDCCH (10-10) including the DCI indicating the non-periodic CSI report #X to the symbol in which the CSI calculation is completed. The above-mentioned symbols for completing CSI calculation refer to the latest symbol among the symbols after the CSI calculation time Z (10-15) of the last symbol occupied by the PDCCH including the DCI indicating CSI report #X, and the symbol after the CSI calculation time Z' (10-25) of the last symbol of the most recent CSI-RS / CSI-IM / SSB opportunity (10-20) of the CSI report #X sent in the uplink time slot n'.

[0287] Fig.10 10-30 shows a view of the CPU occupancy time of a periodic or semi-persistent CSI report according to some embodiments, including the number of reports in the CSI report being configured as "none". When the base station sends a periodic or semi-persistent CSI report #X in an uplink slot n' through a DCI indication using DCI format 0_1 ​​scrambled with higher layer signaling or SP-CSI-RNTI, the CPU occupancy time (13-35) of the CSI report #X sent in the uplink slot n' can be defined from the first symbol of the first transmitted CSI-RS / CSI-IM / SSB resource corresponding to each CSI-RS / CSI-IM / SSB opportunity (10-40) for the CSI report #X sent in the uplink slot n' to the symbol after the CSI calculation time Z' (10-45) of the last symbol of the last transmitted CSI-RS / CSI-IM / SSB resource.

[0288] For example, the rules shown in Table 26 below may be followed.

[0289] [Table 26]

[0290]

[0291]

[0292] Fig.11 A diagram showing a radio protocol structure of a base station and a terminal when performing a single cell, carrier aggregation, and dual connectivity according to some embodiments is shown.

[0293] refer to Fig.11The radio protocols of the next generation mobile communication system include NR Service Data Adaptation Protocol (NRSDAP) 11-25 and 11-70, NR Packet Data Convergence Protocol (NR PDCP) 11-30 and 11-65, NR Radio Link Control (NRRLC) 11-35 and 11-60, and NR Medium Access Control (NR MAC) 11-40 and 11-55 located at the terminal and NR base station respectively.

[0294] The main functions of NR SDAP 11-25 and 11-70 may include some of the following functions.

[0295] -Transmission of user plane data

[0296] - Mapping function between uplink and downlink QoS flows and data bearers (mapping between QoS flows and DRBs for both DL and UL)

[0297] - Marking of QoS flow ID in both DL and UL packets for uplink and downlink

[0298] - Reflective QoS Flow to DRB mapping for UL SDAP PDUs for uplink SDAP PDUs.

[0299] For SDAP layer devices, the terminal can configure whether to use the header of the SDAP layer device or use the function of the SDAP layer device as an RRC message for each PDCP layer device, for each bearer or for each logical channel, and when configuring the SDAP header, the terminal can be instructed to update or reconfigure the mapping information of the QoS flow and data bearer for the uplink and downlink by using a 1-bit indicator (NAS reflective QoS) of the NAS QoS reflective configuration and a 1-bit indicator (AS reflective QoS) of the AS QoS reflective configuration of the SDAP header. The SDAP header may include QoS flow ID information indicating QoS. QoS information can be used as data processing priority and scheduling information to support smooth services.

[0300] The main functions of NR PDCP 11-30 and 11-65 may include some of the following functions.

[0301] -Header compression and decompression (ROHC only)

[0302] -Transmission of user data

[0303] - Deliver upper layer PDUs in sequence

[0304] - Out-of-order delivery of upper layer PDUs

[0305] - Reordering function (PDCP PDU reordering for reception)

[0306] - Duplicate detection of lower layer SDU

[0307] -Retransmission of PDCP SDU

[0308] -Encryption and decryption functions (encryption and decryption)

[0309] - Timer-based SDU discard functionality (Timer-based SDU discard in uplink)

[0310] In the above, the reordering function of the NR PDCP device may refer to a function of reordering the PDCP PDU received from the lower layer based on the PDCP sequence number (SN), may include a function of delivering data to the upper layer in the reordered order, may include a function of directly sending data regardless of the order, may include a function of reordering to record lost PDCP PDUs, may include a function of reporting the status of lost PDCP PDUs to the transmitting side, and may include a function of requesting retransmission of lost PDCP PDUs.

[0311] The main functions of NR RLC 11-35 and 11-60 may include some of the following functions.

[0312] -Data transmission function (transmission of upper layer PDU)

[0313] - Deliver upper layer PDUs in sequence

[0314] - Out-of-order delivery of upper layer PDUs

[0315] -ARQ function (error correction through ARQ)

[0316] - Concatenation, segmentation and reassembly of RLC SDU

[0317] - Re-segmentation of RLC data PDUs

[0318] - Reordering of RLC data PDUs

[0319] - Duplicate detection function

[0320] -Protocol error detection

[0321] -RLC SDU deletion function (RLC SDU discard)

[0322] -RLC reconstruction

[0323] In the above, the NR RLC device delivering in sequence may refer to a function of sending the RLC SDU received from the lower layer to the upper layer in sequence, and when one RLC SDU is initially divided into multiple RLC SDUs and received, it may include a function of reassembling and delivering, and may include a function of rearranging the received RLC PDU based on the RLC sequence number (SN) or the sequence number (PDCP SN), may include a function of recording the lost RLC PDU by rearranging the sequence, may include a function of recording the PDU, may include a function of reporting the status of the lost RLC PDU to the transmitting side, and may include a function of requesting retransmission of the lost RLC PDU, and when there is a lost RLC SDU, it may include a function of forwarding the RLC SDU in sequence upward only (and before the lost RLC SDU) to the lost RLC SDU, or even if there is a lost RLC SDU, if a predetermined timer expires, it may include a function of forwarding all RLC SDUs received before the timer starts to the upper layer in sequence, or even if there is a lost RLC SDU, if a predetermined timer expires, it may include the function of delivering all previously received RLC SDUs to the higher layer in sequence, or even if there is a lost RLC SDU, if a predetermined timer expires, it may include the function of delivering all currently received RLC SDUs to the upper layer in sequence. In addition, the RLC PDUs can be processed in the order in which the RLC PDUs are received (regardless of the sequence number and the sequence number, in the order of arrival), and then delivered to the PDCP device in an arbitrary order (out-of-order delivery), and in the case of segmentation, segments stored in the buffer or received later can be received, reconstructed into a single RLC PDU, processed, and then sent to the PDCP device. The NR RLC layer may not include a cascading function, and this function may be performed in the NR MAC layer or replaced by the multiplexing function of the NR MAC layer.

[0324] In the above, the out-of-order delivery function of the NR RLC device refers to a function of directly sending the RLC SDU received from the lower layer to the upper layer regardless of the order. When one RLC SDU is received by being divided into several RLC SDUs, a function of reassembling and sending may be included, and a function of storing the RLC SN or PDCP SN of the received RLC PDU and sorting it to record the lost RLC PDU may be included.

[0325] NR MAC (11-40, 11-55) can be connected to multiple NR RLC layer devices configured in one terminal, and the main functions of NR MAC may include some of the following functions.

[0326] - Mapping function (mapping between logical channels and transport channels)

[0327] -Multiplexing / demultiplexing of MAC SDU

[0328] -Scheduling information reporting function

[0329] -HARQ function (error correction through HARQ)

[0330] - Priority handling between logical channels (priority handling between logical channels of a UE)

[0331] - Priority handling between UEs (priority handling between UEs with the help of dynamic scheduling)

[0332] -MBMS service identification function

[0333] -Transmission format selection function

[0334] - Fill function

[0335] The NR PHY layers 11-45 and 11-50 may perform channel coding and modulation of upper layer data, make OFDM symbols and transmit them over a radio channel, or demodulate and channel decode OFDM symbols received over a radio channel to an upper layer.

[0336] The detailed structure of the radio protocol structure may vary depending on the carrier (or cell) operation method. For example, when the base station sends data to the terminal based on a single carrier (or cell), the base station and the terminal use a protocol structure with a single structure for each layer, as shown in 11-00. On the other hand, when the base station uses multiple carriers in a single TRP (Tx / Rx point) to send data to the terminal based on carrier aggregation (CA), the base station and the terminal have a single structure up to RLC, as in 11-10, but use a protocol structure to multiplex the PHY layer through the MAC layer. For another example, when the base station uses multiple carriers in multiple TRPs to send data to the terminal based on dual connection (DC), the base station and the terminal have a single structure up to RLC, as in 11-20, but use a protocol structure to multiplex the PHY layer through the MAC layer.

[0337] Referring to the above description of the CSI framework and CPU, in the current NR, when K is configured in the resource setting for channel measurement associated with a certain CSI report or report setting, sWhen a resource is selected, one of the CSI-RS resources is selected as CRI and the relevant CSI is reported. This can be understood as reporting the channel information of the cell / transmission point / panel / beam (hereinafter referred to as the transmit receive point (TRP)), through which the CSI-RS selected by the CRI is transmitted. At the same time, NR version 16 supports non-coherent transmission of each TRP, that is, non-coherent joint transmission (NC-JT), in which the data transmission of each TRP participating in NC-JT interferes with each other. Taking into account the above-mentioned NC-JT interference, the terminal can improve the transmission efficiency of NC-JT by measuring and reporting CSI. The CSI measurement and reporting method applicable to NC-JT may be different from the above-mentioned NR CSI measurement and reporting method. In addition, the number of CPUs of these CSIs of NC-JT may also be different from the number of CPUs defined in the current NR. Accordingly, in the present disclosure, a reasonable CPU number calculation method is provided for CSI measurement and reporting suitable for NC-JT, thereby improving the channel state information reporting efficiency and NC-JT transmission reliability under appropriate terminal complexity.

[0338] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, in describing the present disclosure, when it is determined that the detailed description of the relevant functions or configurations may unnecessarily obscure the subject matter of the present disclosure, the detailed description will be omitted. In addition, the terms to be described later are defined in consideration of the functions in the present disclosure and may vary according to the intention or practice of the user or operator. Therefore, they should be defined based on the content of the entire specification.

[0339] In the following, a base station is a subject that performs resource allocation of a terminal, and may be at least one of a gNode B (gNB), an eNodeB (eNB), a Node B, a base station (BS), a radio access unit, a base station controller, or a node on a network. A 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. In the following, the present disclosure will be described by taking an NR or LTE / LTE-A system as an example, but is not limited thereto, and the embodiments may be applied to various communication systems having similar technical backgrounds or channel types. In addition, the embodiments of the present disclosure may be applied to other communication systems via some modifications within the scope of the present disclosure that are not substantially deviated from the scope of the present disclosure by the judgment of a technician.

[0340] The present disclosure is applicable to both frequency division duplex (FDD) systems and time division duplex (TDD) systems.

[0341] Hereinafter, in the present disclosure, higher-level signaling is a signal transmission method sent from a base station to a terminal using a downlink data channel of a physical layer or from a terminal to a base station using an uplink data channel of a physical layer, and may be referred to as RRC signaling or PDCP signaling or a media access control (MAC) control element (MAC CE).

[0342] Hereinafter, in the present disclosure, when determining whether cooperative communication is applied, the terminal may use a variety of methods, such as allocating a PDCCH to which cooperative communication is applied with a specific format, or allocating a PDCCH to which cooperative communication is applied includes a specific indicator of whether cooperative communication is applied, allocating a PDCCH to which cooperative communication is applied with a specific RNTI for scrambling, or assuming that the application of cooperative communication is in a specific part indicated by an upper layer, etc. Hereinafter, for ease of description, a case in which a terminal receives a PDSCH to which cooperative communication is applied based on conditions similar to those described above will be referred to as an NC-JT case.

[0343] Hereinafter, in the present disclosure, determining the priority between A and B may be referred to in various ways, such as selecting the one with a higher priority to execute its corresponding operation according to a predetermined priority rule, or omitting or discarding the operation with a lower priority.

[0344] Hereinafter, in the present disclosure, the above-mentioned embodiments will be described through multiple embodiments, but these embodiments are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0345] <First embodiment: DCI reception of NC-JT>

[0346] 5G wireless communication systems can support not only services that require high transmission speeds, but also services with extremely short transmission delays and services that require high connection density. In a wireless communication network including multiple cells, transmission and reception points (TRPs) or beams, cooperative transmission between each cell, TRP and / or beam is one of the basic technologies for meeting various service requirements by increasing the signal strength received by the terminal or effectively performing interference control between cells, TRPs or / and beams.

[0347] Joint transmission (JT) is a representative transmission technology of the above-mentioned cooperative communication, and a terminal is supported through different cells, TRPs and / or beams through the joint transmission technology to increase the strength of the signal received by the terminal. At the same time, since the characteristics of the channels of each cell, TRP or / and beam and the terminal may be significantly different, different precoding, modulation and coding schemes (MCS), resource allocation need to be applied to the link between each cell, TRP or / and beam and the terminal. Specifically, in the case where non-coherent joint transmission (NC-JT) supports non-coherent precoding between each cell, it is important to configure separate DL (downlink) transmission information for each cell, TRP or / and beam. At the same time, the separate DL transmission information setting for each cell, TRP and / or beam is the main factor in increasing the payload required for DL ​​DCI transmission, which may have an adverse effect on the reception performance of the physical downlink control channel (PDCCH) that transmits DCI. Therefore, it is necessary to carefully design the trade-off between the amount of DCI information and the PDCCH reception performance for JT support.

[0348] Fig.12 A diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication according to some embodiments in a wireless communication system according to one embodiment is shown.

[0349] refer to Fig.12 , shows an example of joint resource allocation based on TRP according to joint transmission (JT) technology and situations. Fig.12 , 12-00 is an example of coherent joint transmission (C-JT) that supports coherent precoding between each cell, TRP or / and beam. In C-JT, a single data (PDSCH) is sent from TRP A (12-05) and TRP B (12-10) to terminal 12-15, and joint precoding can be performed in multiple TRPs. This may mean that TRP A (12-05) and TRP B (12-10) send the same DMRS port to receive the same PDSCH (for example, DMRS ports A and B in two TRPs). In this case, the terminal can receive one DCI information for receiving one PDSCH demodulated by DMRS ports A and B.

[0350] exist Fig.1212-20 is an example of non-coherent joint transmission (NC-JT) supporting non-coherent precoding between each cell, TRP or / and beam. In the case of NC-JT, the PDSCH is sent to the terminal 12-35 for each cell, TRP or / and beam, and a separate precoding can be applied to each PDSCH. Compared with a single cell, TRP or / and beam transmission, each cell, TRP or / and beam transmits a different PDSCH to improve throughput, or each cell, TRP or / and beam can repeatedly transmit the same PDSCH, thereby improving reliability compared with a single cell, TRP or / and beam transmission.

[0351] Various radio resource allocations can be considered, such as when the frequency and time resources used by multiple TRPs for transmitting PDSCH are the same (12-40), when the frequency and time resources used by multiple TRPs do not overlap at all (12-45), or when certain frequency and time resources used by multiple TRPs overlap (12-50). For the above radio resource allocations, in each case, when multiple TRPs repeatedly send the same PDSCH to improve reliability, if the receiving terminal does not know whether the corresponding PDSCH is repeatedly sent, the corresponding terminal may have limitations in improving reliability because it cannot be combined in the physical layer used for the corresponding PDSCH. Therefore, the present disclosure provides a retransmission instruction and configuration method for improving NC-JT transmission reliability.

[0352] For NC-JT support, various forms, structures, and relationships of DCI can be considered to allocate multiple PDSCHs to a UE at the same time.

[0353] Fig.13 A diagram showing an example of downlink control information (DCI) configuration for cooperative communication in a wireless communication system according to an embodiment. Fig.13 , four examples of DCI designs for NC-JT support are shown.

[0354] exist Fig.13In the example, case #1 (13-00) is a case where the control information of the PDSCH sent in the (N-1) additional TRPs is sent in the same form (same DCI format) as the control information of the PDSCH sent in the service TRP, which is a case where different (N-1) PDSCHs are sent from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the service TRP (TRP#0) used when sending a single PDSCH. That is, the terminal can obtain the control information of the PDSCH sent from different TRPs (DCI#0 to DCI#(N-1)) through DCI (TRP#0 to TRP#(N-1)) having the same DCI format and the same payload). In the above case #1, the degree of freedom of each PDSCH control (allocation) can be fully guaranteed, but when each DCI is sent in a different TRP, the coverage of each DCI may differ and the reception performance may be degraded.

[0355] exist Fig.13In the example, case #2 (13-05) is a case where the control information of the PDSCH sent from the (N-1) additional TRPs is sent in a different form (different DCI format or different DCI payload) from the control information of the PDSCH sent from the serving TRP, which is a case where different (N-1) PDSCHs are sent by the (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to the serving TRP (TRP#0) used when sending a single PDSCH. For example, in the case of DCI#0 for sending control information for the PDSCH sent in the serving TRP (TRP#0), all information elements of DCI formats 1_0 to DCI formats 1_1 are included, but in the case of sending the control information of the PDSCH sent from the collaborative TRP (TRP#1 to TRP#(N-1)) in a "shortened" DCI (sDCI#0 to sDCI#(N-2)), some information elements of DCI formats 1_0 to DCI formats 1_1 may be included. In the case of a "shortened" DCI (sDCI#0 to sDCI#(N-2)) sending control information for a PDSCH sent from a collaborative TRP (TRP#1 to TRP#(N-1)), only some information elements of DCI format 1_0 to DCI format 1_1 may be included. Therefore, in the case of an sDCI sending control information for a PDSCH sent in a collaborative TRP, the payload may be smaller than that of a normal DCI (nDCI) sending PDSCH-related control information sent from a serving TRP, or may include as many reserved bits as the number of bits less than nDCI. In the above case #2, the degree of freedom of each PDSCH control (allocation) may be limited according to the content of the information elements included in the sDCI, but since the reception performance of sDCI is better than that of nDCI, the probability of occurrence of coverage differences for each DCI may be reduced.

[0356] exist Fig.13In the example, case #3 (13-10) is an example in which control information for a PDSCH sent from (N-1) additional TRPs is sent in a format different from that for control information for a PDSCH sent from a serving TRP (different DCI format or different DCI payload), in the case in which (N-1) PDSCHs are sent from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used when sending a single PDSCH. For example, in the case of DCI#0 for sending control information for a PDSCH sent in a serving TRP (TRP#0), all information elements of DCI formats 1_0 to DCI formats 1_1 are included, and in the case of sending control information for a PDSCH from a collaborative TRP (TRP#1 to TRP#(N-1)), only some information elements of DCI formats 1_0 to DCI formats 1_1 may be collected and sent in one "secondary" DCI (sDCI). For example, the sDCI may have at least one of the HARQ-related information, such as frequency domain resource allocation, time domain resource allocation, and MCS of the collaborative TRP. In addition, for information not included in the sDCI, such as a bandwidth part (BWP) indicator or a carrier indicator, the information may follow the DCI (DCI#0, normal DCI, nDCI) of the service TRP. In case #3, the degree of freedom of each PDSCH control (allocation) may be limited depending on the content of the information element included in the sDCI, but the reception performance of the sDCI can be adjusted and compared with case #1 or case #2, and the complexity of DCI blind decoding can be reduced.

[0357] exist Fig.13 In the example of sending control information of PDSCH sent from (N-1) additional TRPs in DCI (long DCI, lDCI) as control information of PDSCH sent from the serving TRP, it is in the case of sending (N-1) PDSCHs from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to the serving TRP (TRP#0) used when sending a single PDSCH. That is, the terminal can obtain control information of PDSCH sent from different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. In case #4, the complexity of DCI blind decoding of the terminal may not increase, but the PDSCH control (allocation) freedom may be lower, such as due to the limited number of collaborative TRPs caused by the long DCI payload limitation.

[0358] In the following description and embodiments, sDCI may refer to various auxiliary DCIs including PDSCH control information sent from a collaborative TRP, such as shortened DCI, auxiliary DCI, or normal DCI (PDI formats 1_0 to 1_1 described above). Unless otherwise specified, the description also applies to various auxiliary DCIs.

[0359] In the following description and embodiments, the above-mentioned case #1, case #2 and case #3 in which one or more DCIs (PDCCH) are used for NC-JT support are divided into multiple PDCCH-based NC-JTs, and in the above-mentioned case #4, a single DCI (PDCCH for NC-JT support) can be classified as a single PDCCH-based NC-JT.

[0360] In the embodiments of the present disclosure, "collaborative TRP" may be replaced with various terms, such as "collaborative panel" or "collaborative beam", in actual applications.

[0361] In the embodiments of the present disclosure, the term "when NC-JT is applied" can be interpreted in various ways depending on the situation, such as "when the terminal simultaneously receives one or more PDSCHs from one BWP", "when the terminal simultaneously receives two or more PDSCHs from one BWP based on a transmission configuration indicator (TCI) indication", "the PDSCH received by the terminal is associated with one or more DMRS port groups (port groups)", etc., but it is used as an expression for ease of explanation.

[0362] In the present disclosure, the radio protocol structure of NC-JT can be used in various ways according to the TRP deployment scenario. For example, if there is no backhaul delay or the backhaul delay between the cooperative TRPs is very small, a structure based on MAC layer multiplexing similar to 11 (11-10) (CA-type method) can be used. On the other hand, a structure similar to Fig.11 (11-20), when the return delay between the cooperating TRPs is large enough to be negligible (for example, when the CSI exchange or scheduling information exchange between the cooperating TRPs takes 2ms or more), it is possible to ensure the use of the robust characteristics in terms of delay for the independent structure of each TRP from the RLC layer (DC-type method).

[0363] <Second embodiment: whether the terminal can report the delivery method of NC-JT CSI>

[0364] The above NR CSI report is configured as sWhen the CSI-RS resource is configured in a resource setting for channel measurement associated with a CSI report or a CSI report setting, a CSI-RS resource is selected as the CRI and the associated CSI is reported. This can be understood as reporting channel information on the TRP through which the CSI-RS selected as the CRI is sent. On the other hand, since NC-JT sends data from multiple transmission points at the same time, each data transmission will interfere with each other. This may mean that the NC-JT transmission efficiency can be improved through CSI reporting, taking into account the interference caused by NC-JT transmission. At the same time, since the above operation requires additional complexity compared to conventional NRCSI reporting, the NC-JT CSI report may be a function that only supports specific terminals, and the terminal may use at least one of the following methods to notify the base station whether NC-JT CSI is supported.

[0365] The terminal can report to the base station whether NC-JT CSI reporting is supported through the terminal capability report. At this time, whether NC-JT CSI reporting is supported may depend on whether NC-JT is supported. For example, NC-JT CSI reporting may only be reported to terminals that support NC-JT, and even terminals that support NC-JT may not support NC-JT CSI reporting. It can be assumed that NC-JT supporting terminals implicitly support NC-JT CSI reporting. Whether NC-JT is supported can be notified to the base station through the terminal capability report.

[0366] It can be assumed that a terminal supporting a specific NR version implicitly supports NC-JT CSI reporting. For example, when the terminal notifies the base station that it is an NR Rel-17 or Rel-16 terminal, it can be assumed that the terminal supports NC-JT CSI reporting.

[0367] The terminal capability report related to the NC-JT CSI report may have different values ​​for each frequency range such as BWP, cell, band, FR1 / FR2.

[0368] <Third Embodiment: Configuration Method of NC-JT CSI Report>

[0369] The following embodiments provide a specific method for configuring a base station to perform NC-JT CSI reporting. The terminal may apply at least one of the following methods to perform NC-JT CSI reporting.

[0370] [Method 3-1] Explicit instructions

[0371] The base station can explicitly indicate whether the terminal performs NC-JT CSI reporting. The corresponding indication can be indicated by an upper layer such as RRC or MAC-CE, L1 signaling. The indicator can be applied to each CSI report, or to the entire CSI report for each BWP or CC, or to the entire CSI report for all CCs. When the indicator is applied for each CSI report, it can be configured in the CSI report setting on the CSI framework, or in the CSI resource setting / resource setting / CSI-RS. Alternatively, it can be configured in the configuration information for irregularly triggering CSI reporting. For example, when the configuration of whether to perform NC-JT CSI reporting is configured in association with non-periodic CSI reporting, this can be interpreted as meaning that NC-JT CSI reporting for periodic CSI reporting or semi-persistent CSI reporting is not performed. Even when configured in conjunction with periodic CSI reporting or semi-persistent CSI reporting, a similar interpretation is possible, but a detailed description is omitted to avoid confusing the subject matter of the present disclosure.

[0372] Whether to perform NC-JT CSI reporting may depend on the terminal capabilities described in the second embodiment. For example, if the terminal reports that NC-JT CSI is not supported, the terminal may not expect the base station to configure an indicator to report NC-JT CSI or ignore the indicator and report NR CSI.

[0373] [Method 3-2] Implicit instructions

[0374] Whether the terminal performs NC-JT CSI reporting can be implicitly indicated by the relationship between parameters. For example, when reporting that the terminal supports NC-JT CSI when reporting the terminal capabilities described in the second embodiment, if the base station configures the CSI framework in a specific manner, it can be understood that the terminal reports that the base station performs NC-JT CSI reporting. For configuring the CSI framework, at least one of the following methods can be applied.

[0375] [Method 3-2-1] Indication of the number of CSI-RS in a CSI resource set

[0376] For NC-JT CSI measurement, each TRP participating in NC-JT transmission can be configured to send an independent CSI-RS. At this time, all CSI-RSs can belong to one CSI-RS resource set, and the CSI-RS resource set can belong to a CSI resource setting for channel measurement. The inclusion relationship between the CSI-RS resource set and the CSI resource setting can be as described in [Table 16]. Therefore, the terminal can be connected to the number of CSI-RS in the CSI-RS resource set K in the report setting. sTo implicitly determine whether to perform NC-JT CSI reporting. For example, if the number of CSI-RS in the CSI-RS resource set is K s =1, the terminal may not perform NC-JT CSI reporting. At the same time, when the number of CSI-RS in the CSI-RS resource set is K s When ≥2, the terminal can perform NC-JT CSI reporting, and the corresponding NC-JT CSI report measures the CSI-RS of two or more TRPs together. Therefore, it can be a CSI report that takes mutual interference into consideration.

[0377] When reporting NC-JT CSI, NC-JT CSI can be measured for all CSI-RS in the CSI-RS resource set, and a specific set of CSI-RS can also be selected in the CSI-RS resource set and the NC-JT CSI for the TRP corresponding to the set can be measured. At this time, the number of elements in the set can be 2 or more, or it can be a set consisting of two or more. At this time, the elements between the sets can overlap with each other. The set can be called an NC-JT collaboration set or a CoMP collaboration set. When two or more groups of CSI-RS for measuring NC-JT CSI are configured, that is, when measuring CSI for two or more groups of CoMP collaboration sets, the terminal can obtain the optimal NC-JT CSI by measuring and comparing the NC-JT CSI corresponding to each set. The terminal can include information about which CSI-RS or TRP set the obtained NC-JT CSI is on in the CSI report, and the information can be information included in the NR CSI report, such as CRI or a new indicator.

[0378] The corresponding NC-JT CSI report may be optional. For example, the terminal may calculate CRI-based CSI for multiple CSI-RS in the same manner as the existing operation, and may also calculate the above-mentioned NC-JT CSI together and compare the two CSIs to optimize the CSI, that is, one of the calculated CSI and NC-JT CSI may be reported according to the existing operation. At this time, the report may include information that enables the base station to know whether to select NC-JT CSI. The information may be information included in the NR CSI report, such as CRI or a new indicator.

[0379] [Method 3-2-2] Indicate by configuring multiple CSI-RS resource sets or resource settings

[0380] For NC-JT CSI measurement, one CSI report setting and two or more CSI resource settings for channel measurement can be connected, and each resource setting can include a CSI-RS sent from each TRP participating in NC-JT transmission. This is different from the conventional NR CSI framework in which one CSI report setting and one CSI resource setting for channel measurement are connected. Alternatively, one resource setting for channel measurement may include two or more CSI-RS resource sets, and each CSI-RS resource set may include a CSI-RS sent by each TRP participating in NC-JT transmission. The association relationship between the CSI report setting and the CSI resource setting for channel measurement may be similar to that described in [Table 20]. In addition, the inclusion relationship between the CSI-RS resource set and the CSI resource setting may be described in [Table 16]. The CSI-RS belonging to multiple CSI resource settings for channel measurement or to multiple resource sets in a single CSI resource setting for channel measurement can be measured together for NC-JT CSI calculation. This is just a single resource set within a single CSI resource setting for channel measurement or a single resource set is selected only through aperiodic CSI triggering, etc., and can be distinguished from the NR CSI framework that performs CSI measurement only for the CSI-RS in this resource set.

[0381] Fig.14 An example of a CSI frame structure and a CSI-RS configuration for NC-JT CSI measurement when two CSI-RS resource sets are configured in a CSI resource setting is shown. Depending on the number of CSI-RSs in the CSI-RS resource set, cases where the number of CSI-RSs is one (case A) and two or more (case B) can be considered.

[0382] In case A (14-01), the first resource set (14-11) of the CSI-RS resource set (14-10) corresponds to the first TRP participating in the NC-JT transmission, and the second resource set Silver (14-12) corresponds to the second TRP. This can be a configuration for measuring the CSI of one CoMP collaboration set. The terminal can calculate the NC-JT CSI by measuring the CSI-RS (14-20) in the CSI-RS resource set for RS and the channel measurement set for interference measurement from outside the NC-JT.

[0383] In case B (14-51), the terminal can measure the NC-JT CSI of multiple CoMP collaboration sets and perform reporting on one of the CSIs. For example, NC-JT CSI#1 can be measured by measuring the first CSI-RS of the CSI-RS resource set and the first CSI-IM resource in the CSI-IM resource set (14-60). That is, the NC-JT CSI#1 of the first CoMP collaboration set can be measured. In addition, NC-JT CSI#2 can be measured by measuring the second CSI-RS of the CSI-RS resource set and the second CSI-IM resource in the CSI-IM resource set (14-70). That is, the NC-JT CSI#1 of the second CoMP collaboration set can be measured. The best NC-JT CSI can be selected and reported among the multiple NC-JT CSIs measured similarly to the above (14-80). At this time, information on which NC-JT CSI was selected can also be reported, and the information can be information based on CRI.

[0384] Above Fig.14 The example handles the case of configuring multiple CSI-RS resource sets in a single CSI resource setting for NC-JT CSI reporting, and can be similarly applied when configuring multiple CSI resource settings for channel measurement, but the detailed description is omitted so as not to confuse the key points of the explanation.

[0385] The reporting of NC-JT CSI by [Method 3-2] may be performed only under specific conditions. Here, the specific conditions may include at least one of the following conditions.

[0386] As a condition, whether to perform NC-JT CSI reporting may depend on the terminal capabilities described in the second embodiment. If the terminal reports that NC-JT CSI is not supported, the terminal may report NR CSI. At this time, in the case of [Method 3-2-1], NR CSI may represent CRI-based CSI, and in the case of [Method 3-2-2], it may represent CSI measured for the first or specific order in multiple CSI resource settings for channel measurement. Alternatively, it may represent CSI measured for a CSI-RS resource set corresponding to the first or specific order in a single CSI resource setting for channel measurement.

[0387] As another condition, NC-JT CSI reporting can only be performed when an explicit indicator for NC-JT CSI reporting is operated in conjunction with [Method 3-2] and the explicit indicator is set. To this end, for example, if [Method 3-2-1] is followed, the terminal cannot distinguish between the NC-JT CSI reporting configuration and the CRI-based reporting configuration. Therefore, there may be a problem of unnecessarily increasing the complexity of the terminal by always reporting NC-JT CSI and a mismatch in understanding between the base station and the terminal, that is, the base station predicts a CRI-based report, but the CSI mismatch is caused by the terminal reporting NC-JT CSI. This problem can be solved by combining the use of the above-mentioned explicit indicator. A similar explanation is possible when multiple CSI-RS resource sets are configured in a single CSI resource setting for channel measurement according to [Method 3-2-2].

[0388] As another condition, NC-JT CSI reporting may be limited to specific time domain behaviors. For example, if all time domain behaviors allow NC-JT CSI reporting, the computational complexity of the terminal may be very large, so NC-JT CSI is measured and reported only in the case of non-periodic reporting, and CSI may be measured and reported in the case of semi-persistent or periodic reporting. The conditions for measuring and reporting NC-JT CSI may change. For example, it can be changed to non-periodic and semi-persistent reporting conditions or non-periodic CSI-RS triggering and non-periodic CSI reporting conditions. Alternatively, since the payload required for NC-JT CSI reporting may be larger than the CSI payload, the above conditions can be changed to conditions limited to non-periodic and / or semi-persistent reporting reported in PUSCH.

[0389] As another condition, the number of CSI-RSs used for NC-JT CSI reporting may be limited. For example, when [Method 3-2-1] is applied, only for 1<K s ≤N, the number of CSI-RS in the CSI-RS resource set performs NC-JT CSI reporting, and in other cases, CRI-based NR CSI reporting can be performed. In order to reduce the terminal complexity required for CSI calculation, the value of N can be 2.

[0390] As another case, whether to report NC-JT CSI can be determined based on the total CPU capability of the terminal and the number of CPUs that the terminal has calculated. CPU , then the number of CPUs that the terminal has used to calculate CSI is called O CPU , and the number of CPUs required to calculate NC-JT CSI is called X. The terminal can perform NC-JT reporting only when the following equation is satisfied.

[0391] [Equation 2]

[0392] N CPU -O CPU ≥X

[0393] On the other hand, if the above [Equation 2] is not satisfied and the following [Equation 3] is satisfied, the terminal may perform NRCSI reporting.

[0394] [Equation 3]

[0395] Y≤N CPU -O CPU <X

[0396] In [Equation 3], Y = K S Y is the number of CPUs required to perform NR CSI reporting and can be used for K s Whether the CSI-RS resource of the measurement channel is connected to the corresponding CSI report configuration. The value X of [Equation 2] and [Equation 3] may be a value obtained by the following fourth embodiment or other methods.

[0397] <Fourth Embodiment: Number of CPUs for NC-JT CSI Reporting>

[0398] When the terminal measures and reports NC-JT CSI, it can be assumed that the CPU calculation for NC-JT CSI reporting is different from the CPU calculation for reporting NR CSI because the interference caused by JC-JT transmission needs to be considered, which is different from the conventional NR CSI reporting. In this embodiment, a detailed method for determining the number of CPUs for measuring and reporting NC-JT CSI is described. At this time, the terminal configured to report NC-JT CSI can ensure that the number of CSI-RSs connected to the corresponding CSI reporting setting is K s ≤ N only satisfies NC-JT CSI reporting. The value of N can be 2.

[0399] [Method 4-1] In K s How to calculate the number of CPUs when =2

[0400] When the CSI-RS for channel measurement is configured as K for NC-JT CSI measurement and reporting s=2, this method can be applied. This configuration can be formed by configuring two CSI-RS settings in the CSI-RS resource set mentioned in [Method 3-2-1], connecting the single CSI report setting for channel measurement in [Method 3-2-2] and the two CSI resource settings, and configuring a single CSI resource setting for channel measurement through two CSI-RS resource sets or other methods. The association relationship between the CSI report setting for channel measurement and the CSI resource setting can be similar to that described in [Table 20]. In addition, the inclusion relationship between the CSI-RS resource set and the CSI resource setting can be described in [Table 16].

[0401] As mentioned above, the terminal computational complexity required to measure and report NC-JT CSI may be different from the computational complexity required to measure and report NR CSI. If the number of CPUs required to measure and report NC-JT CSI is named X 1 , then it may be greater than the number of NR CSI CPUs X 2 X can be defined in various ways. 1 For example, X 1 May be a value other than that used for X 2 In addition to the number of CPUs used, the number of additional CPUs used for additional CSI calculations is also considered. As another example, X 1 It may be a value independently determined in consideration of the complexity of the terminal used to calculate the NC-JT CSI, and is different from the value used for X 2 The number of CPUs is irrelevant.

[0402] If X 1 is defined as "a value that takes into account all 2 The number of additional CPUs for additional CSI calculations in addition to the number of CPUs used for additional CSI calculations can be calculated by 1 -X 2 At least one of the following explanations applies.

[0403] Explanation 4-1-1. X = a value equal to or proportional to the number of CSI-RSs

[0404] Since the additional calculation can be explained as being performed considering the NC-JT interference of each CSI-RS for channel measurement, i.e., TRP,X=αK s , where α is a constant with 1 or other positive value, K s is the number of channel CSI-RS used for measurement.

[0405] Explanation of 4-1-2. X = β (constant)

[0406] Since the additional calculation can be explained by reflecting the NC-JT interference to the entire CSI of each TRP measured simultaneously to update, X=β can be set, and β can be a value independent of the number of CSI-RSs measured for the channel used for NC-JT CSI measurement. β is a constant with 1 or other positive values.

[0407] If X 1 is defined as “a value used to calculate NC-JT CSI that is determined independently of the value used to calculate X, taking into account the complexity of the terminal 2 If the number of CPUs is ", at least one of the following explanations applies to X 1 .

[0408] Explanation 4-2-1. X 1 = A value equal to or proportional to the number of CSI-RS

[0409] This calculation can be interpreted as being proportional to the CSI-RS used for channel measurement, i.e., TRP, X 1 =βK s , where β is a constant with 2 or other positive value.

[0410] Explanation 4-2-2. X 1 =N CPU (N CPU =Total CPU capacity of the terminal)

[0411] The calculation process may vary between terminal implementations, and from a conservative point of view, the terminal can assume that it always uses its total CPU power N CPU to perform NC-JT CSI measurement and reporting. In this case, N CPU It can be the value reported by the terminal to the base station through the above-mentioned terminal capability report. Alternatively, when the terminal measures and reports NC-JT CSI, similar to the case of reporting according to the delay requirement 1 of NRCSI, the terminal uses its total CPU capacity, only when CSI is not calculated. By calculating NC-JT CSI, NC-JT CSI can be regarded as X 1 =N CPU The above “only when the CSI has not been calculated” may be interpreted as being replaced by “if the CSI has been calculated, all calculations are stopped”.

[0412] At the same time, the above explanations can be applied differently according to conditions. For example, in the case of non-periodic CSI reporting, interpretation 4-2-2 can be applied, and in other words, in the case of periodic or semi-persistent CSI reporting, the remaining analysis can be applied. This can be interpreted as non-periodic CSI reporting requiring urgent NC-JT CSI calculation and reporting, while periodic or semi-persistent CSI reporting is relatively non-urgent NC-JT CSI calculation and reporting. Alternatively, for NC-JT CSI reporting, when all conditions except the number of CSI-RS in delay requirement 1 are met, analysis 4-2-2 can be applied, and the rest of the above analysis can be applied. In non-periodic CSI reporting, if analysis 4-2-2 is applied according to the conditions, it can be considered that there is a stricter delay requirement than when analysis 4-2-2 is not applied, and the delay requirement can refer to the above [Table 21], [Table 22] or the new requirements.

[0413] [Method 4-2] Method for calculating the number of CPUs when N>2

[0414] This method is applicable to the case where the number of CoMP coordination sets is two or more, or the size of the CoMP coordination set is greater than two. These cases can be interpreted as, for example, the number of CSI-RS is K in [Method 3-2-1] s >2, and the case where two or more CSI-RSs are configured in each CSI-RS resource set or CSI resource setting in [Method 3-2-2]. In this case, different CPU counts can be considered for the following two cases.

[0415] Case i) Only some possible CoMP cooperating sets are considered; for example, when only the CoMP cooperating set size is a constant K is considered

[0416] Case ii) Consider all possible CoMP coordination sets; when considering the configurable number of CSI-RS or TRP K, for example s All CoMP coordination timing

[0417] Number of CPUs for case i: The following two interpretations are possible.

[0418] Explanation 4-3-1: It can be interpreted that each CoMP cooperation set considered when calculating NC-JT CSI occupies an independent CPU. The number of CPUs occupied by each CoMP cooperation set may vary depending on the size of the set, and in this case, the total number of CPUs may be M*X because all CoMP cooperation sets have the same size. M may indicate the number of CoMP cooperation sets. X is the number of CPUs required for each CoMP cooperation set and may be a value obtained according to analysis 4-1-1, 4-1-2, or 4-2-1.

[0419] Explanation 4-3-2: Alternatively, in the above case, a specific TRP may be included in multiple CoMP cooperating sets, and the CPU used to calculate the CSI of each CoMP cooperating set may not be considered independently. At this time, since there are multiple ways to calculate the exact number of CPUs and it may vary depending on the implementation of the terminal, it can be simply assumed that the total number of CPUs is N CPU . N CPU It may be the value reported by the terminal to the base station through the above-mentioned terminal capability report.

[0420] Number of CPUs for case ii: The following two explanations are possible.

[0421] Explanation 4-4-1: It can be interpreted that each CoMP cooperation set considered when calculating NC-JT CSI occupies an independent CPU. The number of CPUs occupied by each CoMP cooperation set can vary depending on the size of the set i, and the number of CPUs can be referred to as X i In this case, X i It can be the value obtained from analysis 4-1-1, 4-1-2 or 4-2-1. Finally, the total number of CPUs can follow the following equation.

[0422] [Equation 4]

[0423]

[0424] Explanation 4-2: In the above case, a specific TRP may be included in multiple CoMP cooperation sets, and the CPU used to calculate the CSI of each CoMP cooperation set may not be considered independently. At this time, there are multiple methods for calculating the exact number of CPUs, and the method may vary depending on the implementation of the terminal, so it can be simply assumed that the total number of CPUs is N CPU . N CPU It may be the value reported by the terminal to the base station through the above-mentioned terminal capability report.

[0425] Different interpretations of the number of CPUs can be applied to the above [Method 4-1] and [Method 4-2]. For example, analysis 4-1-1 can be applied to [Method 4-1], and analysis 4-3-2 can be applied to case i of [Method 4-2]. In addition to the above methods, there can be various application methods, but in order not to confuse the subject of this specification, not all possibilities are listed.

[0426] Fig.15 A flowchart of the NC-JT CSI reporting process according to an embodiment is shown. According to the process of configuring NC-JT CSI reporting according to an embodiment, the terminal reports NC-JT CSI according to the settings, and it is assumed that the number of CPUs used for reporting can be expressed as Fig.15 Flowchart of the process.

[0427] The terminal can report the capabilities supported by the terminal to the corresponding base station when connected to the serving base station (15-01). The report can be reported based on the terminal capability query message sent from the base station. The base station can determine whether the terminal can report NC-JT CSI based on the capabilities supported by the terminal (15-02). As a result of the determination, if the terminal is able to report NC-JT CSI, the base station can request the terminal to report NC-JT CSI to indicate the setting of the NC-JT CSI report (15-03). As a result of the determination, if the terminal cannot report NC-JT CSI, the base station can request the terminal to report CSI indicating the NR CSI report setting (15-04).

[0428] When the terminal receives a request for an NC-JT CSI report, the terminal can determine whether the NC-JT CSI reporting condition is met based on the request for the NC-JT CSI report (15-05). When the NC-JT CSI reporting condition is met, the terminal can send an NC-JT CSI report to the base station (15-06). At this time, the NC-JT CSI can be measured, and the number of CPUs used to report the NC-JT CSI can be determined. However, if the NC-JT CSI reporting condition is not met, an NR CSI report can be sent and the NR CSI CPU occupancy can be determined (15-07).

[0429] After the terminal sends the NC-JT CSI report to the base station, the terminal can determine the number of CSI-RSs related to the CSI report (15-08). As a result of the determination, when the number of CSI-RSs is equal to a predetermined threshold, the CPU number calculation method (15-9) can be performed through [Method 4-1]. When the number of CSI-RSs is greater than the predetermined threshold, the CPU number calculation method (15-10) can be performed through [Method 4-2].

[0430] <Fifth embodiment: CSI configuration according to NC-JT transmission type>

[0431] The above-mentioned NC-JT transmission can be divided into a method in which TRPs in a CoMP cooperative set send different data to improve downlink transmission efficiency, and a method in which TRPs in a CoMP cooperative set send the same data to improve downlink transmission reliability. In the method in which TRPs send different data, the time-frequency resources allocated to each TRP may overlap with each other, and interference between TRP transmission signals may occur in the overlapping time-frequency resources. In the method in which TRPs send the same data, since the time-frequency resources allocated to each TRP do not overlap with each other (orthogonal), there may be no interference between TRP transmission signals.

[0432] The following can be considered as a method of allocating TRP resources so that there is no overlap when TRPs send the same data.

[0433] [Method 5-1] A method of allocating time resources to all TRPs and allocating frequency resources that do not overlap with each other.

[0434] The method can be used to reduce data transmission delay time when there are many available frequency resources in the network, and the terminal has the ability to receive multiple TRP transmission signals simultaneously. As an example of a method for allocating non-overlapping frequency resources to each TRP, for two TRP transmissions, an even precoding group (PRG) in the frequency axis resource allocation indicated in the PDSCH scheduling DCI can be allocated to the first TRP and an odd PRG can be allocated to the second TRP. If the size of the PRG is configured as broadband, if the number of RBs allocated by the frequency axis resource allocation indicated by the PDSCH scheduling DCI is N_RB, then The first RB can be allocated to the first TRP, and The remaining RBs can be allocated to the second TRP. At the same time, one codeword can be sent on all resources allocated to all TRPs, or each TRP can send a codeword individually from the resources allocated to it. For example, both the first TRP and the second TRP can send codeword #1 from all allocated resources, or the first TRP can send codeword #A from the resources allocated to it, and the second TRP can send codeword #B from the resources allocated to it. At this time, codeword #A and codeword #B indicate codewords that encode the same data. The terminal can report whether NC-JT transmission can be received based on resource allocation and individual codeword transmission methods through a terminal capability report.

[0435] [Method 5-2] A method in which TRPs allocate time resources that do not overlap with each other and allocate the same frequency resources to all TRPs.

[0436] This method can be used when there are fewer frequency resources available in the network or the terminal does not have the ability to receive transmission signals of multiple TRPs at the same time. As an example of a method for allocating non-overlapping time resources to each TRP, for two TRP transmissions, a specific OFDM symbol in a transmission slot can be allocated to the first TRP, and other specific OFDM symbols can be allocated to the second TRP. The number of OFDM symbols allocated to the TRPs may be the same. As another example, different transmission slots may be allocated to each TRP. For example, a first transmission slot may be allocated to the first TRP, and a second transmission slot may be allocated to the second TRP. The number and symbol position of OFDM symbols indicated for data transmission in each of the above transmission slots may be the same. The number of transmission slots allocated to each TRP may be two or more. The terminal can report whether each of the above methods, i.e., a method in which multiple TRPs perform NC-JT transmission in different time resource allocations in one slot, or a method in which multiple TRPs perform NC-JT transmission in multiple slots, can be received through a terminal capability report.

[0437] The base station can dynamically change the above-mentioned NC-JT transmission method. For example, the base station can indicate through L1 signaling (such as DCI) which of the NC-JT transmission methods in which each TRP in the CoMP cooperation set sends different data or the NC-JT transmission method in which each TRP sends the same data. In order to correctly select the NC-JT transmission method, the base station can configure the CSI report separately according to each transmission mode of NC-JT. For example, as described in [Method 3-1], if whether to perform NC-JT CSI reporting is explicitly configured, the NC-JT transmission method for the NC-JT-CSI to be reported can be configured together. For example, as described in [Method 3-2], if whether to perform NC-JT CSI reporting is implicitly configured, the NC-JT transmission method for the NC-JT-CSI to be reported can be configured together.

[0438] The above-mentioned configuration method for the NC-JT transmission method can be explicitly configured similar to the configuration method for performing NC-JT reporting described in [Method 3-1]. Alternatively, the NC-JT transmission method can be implicitly configured as described in [Method 3-2]. In the case of the above-mentioned explicit or implicit configuration, CSI measurement and / or reporting for one NC-JT transmission method can be configured, or CSI measurement and / or reporting for multiple NC-JT transmission schemes can be configured at the same time. That is, it can be configured to measure and / or report two CSIs for each TRP used to transmit different data and all TRPs that transmit the same data. For example, in the case of implicit configuration, the terminal can simultaneously measure the existing NR CSI, the CSI of the NC-JT transmission method for sending different data for each TRP, and the CSI of the NC-JT transmission method for configuring the same data for each TRP, and select one of these measured CSIs for reporting. At this time, information about the CSI selected for reporting can be included in the CSI report as a CRI or a new indicator. Meanwhile, in the above-mentioned embodiments, the base station may not be configured for CSI reporting that does not support the NC-JT transmission method as a UE capability, or the UE may not expect a corresponding configuration.

[0439] Relative to the method in which all TRPs send the same data in the above-mentioned NC-JT transmission method, the corresponding NC-JT CSI measurement method can be changed according to the resource allocation method of each TRP. Therefore, when configuring NC-JT CSI measurement and / or reporting, in addition to the NC-JT transmission method, the resource allocation method for each TRP can also be configured together, and this configuration method can be similar to the explicit or implicit configuration method of the JT transmission method for the above-mentioned NC-JT CSI measurement and / or reporting.

[0440] Whether to perform the above-mentioned NC-JT transmission and the method and measurement method of NC-JT CSI according to the resource allocation method for each TRP can be defined by the above-mentioned CSI reference signal. In other words,

[0441] Case 1) The case of following the NC-JT transmission method of sending data per TRP.

[0442] Case 2-1) A case following the NC-JT transmission method in which all TRPs send the same data, and a method in which all TRPs in [Method 5-1] send one codeword by allocating resources via TRP.

[0443] Case 2-2) A case in which the NC-JT transmission method is followed in which all TRPs send the same data, and a method in which each TRP in [Method 5-1] sends a codeword individually through resource allocation for each TRP.

[0444] Case 3-1) A case following the NC-JT transmission method in which all TRPs send the same data and resource allocation in the same time slot in [Method 5-2] through resource allocation via TRP.

[0445] Case 3-2) follows the NC-JT transmission method and resource allocation for each TRP, where resources are allocated through TRP between different time slots in [Method 5-2].

[0446] CSI reference signals for five cases may be defined respectively. The terminal may be instructed by the terminal through the above configuration method to determine the CSI according to which reference signal definition.

[0447] Next, the number of CPUs used for NC-JT CSI reporting can vary depending on the NC-JT transmission method configured for CSI reporting and resource allocation method for each TRP. For example, in case 1), the number of CPUs required can be X described in Example 3. 1 , while in case 2-1) to case 3-2), the number of CPUs required can be a new value, such as X3. In case 2-1) to case 3-2), since different time-frequency resources are used between TRPs, interference between TRPs may not need to be considered. Therefore, X3 can be equal to X 1 or less than X 1 The above [Method 4-1] to [Method 4-2] can be applied to X3, and can be configured differently from X 1 Parameters. For example, when the above analysis 4-2-1 is applied, X3 = β_3K_s can be defined, and β_3 can be a constant with a positive value less than 2 or 2. For example, β_3 = 1. In addition to this, various embodiments are possible, but in order not to confuse the subject matter of this specification, not all possibilities are listed.

[0448] Fig.16 A diagram showing a terminal structure in a wireless communication system according to an embodiment.

[0449] refer to Fig.16 , the terminal may include a transceiver 16-00, a memory 16-05, and a processor 16-10. The transceiver 16-00 and the processor 16-10 of the terminal may operate according to the communication method of the above-mentioned terminal. However, the components of the terminal are not limited to the above-mentioned examples. For example, the terminal may include more or less components than the above-mentioned components. In addition, the transceiver 16-00, the memory 16-05, and the processor 16-10 may be implemented in the form of a single chip.

[0450] The transceiver 16-00 can send signals to the base station and receive signals from the base station. Here, the signal may include control information and data. To this end, the transceiver 16-00 may include an RF transmitter that up-converts and amplifies the frequency of the transmitted signal, and an RF receiver that amplifies the received signal with low noise and down-converts the frequency. However, this is only an embodiment of the transceiver 16-00, and the components of the transceiver 16-00 are not limited to the RF transmitter and the RF receiver.

[0451] The transceiver 16 - 00 may receive a signal through a wireless channel and output the signal to the processor 16 - 10 , and transmit a signal output from the processor 16 - 10 through a wireless channel.

[0452] The memory 16-05 may store programs and data necessary for the operation of the terminal. In addition, the memory 16-05 may store control information or data included in a signal sent or received by the terminal. The memory 16-05 may include a storage medium such as a ROM, RAM, hard disk, CD-ROM and DVD or a combination of storage media. In addition, multiple memories 16-05 may be provided.

[0453] In addition, the processor 16-10 can control a series of processes so that the terminal operates according to the above embodiment. For example, the processor 16-10 can control the components of the terminal to receive multiple PDSCHs simultaneously by receiving a DCI composed of two layers. There may be multiple processors 16-10, and the processor 16-10 can perform the component control operation of the terminal by executing the program stored in the memory 16-05.

[0454] Fig.17 A diagram showing a structure of a base station in a wireless communication system according to an embodiment.

[0455] refer to Fig.17 , the base station may include a transceiver 17-00, a memory 17-05, and a processor 17-10. The transceiver 17-00 and the processor 17-10 of the base station may operate according to the communication method of the base station. However, the components of the base station are not limited to the above examples. For example, the base station may include more or less than the above components. In addition, the transceiver 17-00, the memory 17-05, and the processor 17-10 may be implemented in the form of a single chip.

[0456] The transceiver 17-00 can send a signal to a terminal or receive a signal from a terminal. Here, the signal may include control information and data. To this end, the transceiver 17-00 may be configured with an RF transmitter that up-converts and amplifies the frequency of the transmitted signal and an RF receiver that amplifies the received signal with low noise and down-converts the frequency. However, this is only an embodiment of the transceiver 17-00, and the components of the transceiver 17-00 are not limited to the RF transmitter and the RF receiver.

[0457] The transceiver 17 - 00 may receive a signal through a wireless channel, output the signal to the processor 17 - 10 , and transmit a signal output from the processor 17 - 10 through the wireless channel.

[0458] The memory 17-05 may store programs and data necessary for the operation of the base station. In addition, the memory 17-05 may store control information or data included in a signal sent or received by the base station. The memory 17-05 may include a storage medium such as a ROM, RAM, hard disk, CD-ROM and DVD or a combination of storage media. In addition, a plurality of memories 17-05 may be provided.

[0459] The processor 17-10 can control a series of processes so that the base station operates according to the above-mentioned embodiment. For example, the processor 17-10 can configure two layers of DCI including allocation information for multiple PDSCHs and control each component of the base station to send them. There may be multiple processors 17-10, and the processor 17-10 can perform component control operations of the base station by executing the program stored in the memory 17-05.

[0460] The method disclosed in the claims and / or the method according to the various embodiments described in the specification of the present disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0461] When the method is implemented by software, a computer-readable storage medium for storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors in an electronic device. At least one program may include instructions that cause the electronic device to perform the method defined by the attached claims and / or disclosed herein according to various embodiments of the present disclosure.

[0462] The program (software module or software) can be stored in a non-volatile memory, which includes random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk storage, compact disc ROM (CD-ROM), digital versatile disk (DVD) or other types of optical storage devices or tapes. Alternatively, any combination of some or all of them can form a memory in which the program is stored. In addition, multiple such memories may be included in the electronic device.

[0463] In addition, these programs can be stored in an attachable storage device that can access the electronic device through a communication network such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), and a storage area network (SAN), or a combination thereof. Such a storage device can access the electronic device via an external port. In addition, a separate storage device on a communication network can access the portable electronic device.

[0464] In the above detailed embodiments of the present disclosure, the elements included in the present disclosure are expressed in the singular or plural, depending on the detailed embodiments presented. However, for ease of description, the singular form or plural form is appropriately selected for the presented situation, and the present disclosure is not limited to elements expressed in the singular or plural. Therefore, an element expressed in the plural may also include a single element, or an element expressed in the singular may also include multiple elements.

[0465] The embodiments of the present disclosure described and shown in the specification and the drawings are presented for the purpose of easily explaining the technical content of the present disclosure and helping to understand the present disclosure, and are not intended to limit the scope of the present disclosure. That is, on the basis of the technical spirit of the present disclosure, other modifications and changes may be made to it, which will be apparent to those skilled in the art. In addition, if necessary, the above corresponding embodiments may be used in combination. For example, embodiments 1 and 2 of the present disclosure may be partially combined to operate a base station and a terminal. In addition, although the above embodiments have been described by an FDD LTE system, other variations based on the technical concepts of the embodiments may be implemented in other systems such as TDD LTE, 5G, and NR systems.

[0466] Although the present disclosure has been described with various embodiments, various changes and modifications may occur to those skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receiving configuration information related to a channel state information reference signal CSI-RS resource set for channel measurement from a base station, wherein the CSI-RS resource set includes two sets of non-zero power NZP CSI-RS resources; Measuring non-coherent joint transmission (NC-JT) CSI based on the configuration information related to the CSI-RS resource set; and sending a CSI report to the base station based on the measured NC-JT CSI, wherein each of the two sets includes at least two NZP CSI-RS resources among the plurality of NZP CSI-RS resources in the CSI-RS resource set, and The same NZP CSI-RS resource is associated with the two sets.

2. The method according to claim 1, further comprising: Measuring the CSI of a single transmit and receive point TRP, The CSI report includes CSI selected from the CSI of the single TRP and the NC-JT CSI of multiple TRPs.

3. The method according to claim 1, further comprising: Report capability information indicating whether the terminal supports the NC-JT CSI to the base station.

4. The method according to claim 1, further comprising: identifying the number of CSI processing units CPU used to calculate the NC-JT CSI based on the two sets of measurements, wherein the number of CPUs used to calculate the NC-JT CSI is proportional to the number of NZP CSI-RS resources included in each of the two sets, and The number of CPUs for the NC-JT CSI are occupied to calculate the NC-JT CSI.

5. A method performed by a base station in a wireless communication system, the method comprising: Sending configuration information related to a channel state information reference signal CSI-RS resource set for channel measurement to a terminal, wherein the CSI-RS resource set includes two sets of non-zero power NZP CSI-RS resources; and receiving a CSI report including a non-coherent joint transmission (NC-JT) CSI from the terminal based on the configuration information related to the CSI-RS resource set, wherein each of the two sets includes at least two NZP CSI-RS resources among the plurality of NZP CSI-RS resources in the CSI-RS resource set, and The same NZP CSI-RS resource is associated with the two sets.

6. The method according to claim 5, further comprising: Capability information indicating whether the terminal supports the NC-JT CSI is received from the terminal. 7 . The method according to claim 5 , wherein the number of CSI processing units CPUs associated with the NC-JT CSI based on the two sets is proportional to the number of NZP CSI-RS resources included in each of the two sets.

8. A terminal in a wireless communication system, comprising: a transceiver configured to transmit and receive at least one signal; as well as a controller coupled to the transceiver and configured to: Receiving configuration information related to a channel state information reference signal CSI-RS resource set for channel measurement from a base station, wherein the CSI-RS resource set includes two sets of non-zero power NZP CSI-RS resources; Measuring non-coherent joint transmission (NC-JT) CSI based on the configuration information related to the CSI-RS resource set; and sending a CSI report to the base station based on the measured NC-JT CSI, wherein each of the two sets includes at least two NZP CSI-RS resources among the plurality of NZP CSI-RS resources in the CSI-RS resource set, and The same NZP CSI-RS resource is associated with the two sets.

9. The terminal according to claim 8, wherein: The controller is also configured to: Measuring the CSI of a single transmit and receive point TRP, The CSI report includes CSI selected from the CSI of the single TRP and the NC-JT CSI of multiple TRPs.

10. The terminal according to claim 8, wherein: The controller is also configured to: identifying the number of CSI processing units CPU used to calculate the NC-JT CSI based on the two sets of measurements, wherein the number of CPUs used to calculate the NC-JT CSI is proportional to the number of NZP CSI-RS resources included in each of the two sets, and The number of CPUs for the NC-JT CSI are occupied to calculate the NC-JT CSI.

11. The terminal according to claim 8, wherein: The controller is also configured to: Report capability information indicating whether the terminal supports the NC-JT CSI to the base station.

12. A base station in a wireless communication system, comprising: a transceiver configured to transmit and receive at least one signal; as well as a controller coupled to the transceiver and configured to: Sending configuration information related to a channel state information reference signal CSI-RS resource set for channel measurement to a terminal, wherein the CSI-RS resource set includes two sets of non-zero power NZP CSI-RS resources; as well as receiving a CSI report including a non-coherent joint transmission (NC-JT) CSI from the terminal based on the configuration information related to the CSI-RS resource set, wherein each of the two sets includes at least two NZP CSI-RS resources among the plurality of NZP CSI-RS resources in the CSI-RS resource set, and The same NZP CSI-RS resource is associated with the two sets.

13. The base station according to claim 12, The number of CSI processing units CPUs associated with the NC-JT CSI based on the two sets is proportional to the number of NZP CSI-RS resources included in each of the two sets.

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