Method and apparatus for reporting channel state information in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method performed by a terminal in a communication system according to an embodiment of the present disclosure comprises the steps of: receiving a bitmap for indicating a sub-band for channel state information (CSD) reporting from a base station; generating CSI based on one or more sub-bands for CSI reporting based on bitmap identification; and transmitting the CSI to the base station, wherein the one or more sub-bands are identified by using a first method or a second method for identifying the one or more sub-bands by interpreting the bitmap.

Description

Technical Field

[0001] The present disclosure relates to methods and apparatus for reporting channel state information in a wireless communication system. Background Art

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services, and these technologies can be applied not only to frequency bands "below 6 GHz", such as 3.5 GHz, but also to frequency bands "above 6 GHz", called millimeter waves, including 28 GHz and 39 GHz. In addition, in order to achieve a transmission rate fifty times faster than 5G mobile communication technology and an ultra-low latency one-tenth of 5G mobile communication technology, 6G mobile communication technology (called Beyond 5G System) is considered to be implemented in the terahertz band (e.g., 95 GHz to 3 THz band).

[0003] In the initial stage of 5G mobile communication technology, in order to support services and meet performance requirements associated with enhanced mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), and massive machine type communication (mMTC), standardization has been underway on the following technologies: beamforming and massive MIMO for mitigating radio wave path loss and increasing radio wave transmission distance in millimeter waves, parameter sets for dynamic operation of efficient utilization of millimeter wave resources and time slot formats (e.g., operating multiple subcarrier spacings), initial access technology supporting multi-beam transmission and broadband, definition and operation of BWP (bandwidth part), new channel coding methods (such as LDPC (low-density parity check) codes for large-capacity data transmission and polar codes for highly reliable transmission of control information), L2 preprocessing, and network slicing that provides dedicated networks customized for specific services.

[0004] Currently, in view of the services that 5G mobile communication technology will support, discussions are underway on improvements and performance enhancements of initial 5G mobile communication technology, and there is already physical layer standardization on technologies such as: Vehicle-to-Everything (V2X) for assisting driving determination of autonomous vehicles based on information about the location and status of the vehicle transmitted by the vehicle and for enhancing user convenience, New Radio Unlicensed (NR-U) for system operation in unlicensed frequency bands that complies with various regulatory requirements, NR UE power save, NTN (Non-Terrestrial Network), which is UE-satellite direct communication for ensuring coverage and positioning in areas where communication with terrestrial networks is not available.

[0005] In addition, in the field of radio interface architecture / protocol, standardization is being conducted on technologies such as the Industrial Internet of Things (IIoT) for supporting new services through interworking and integration with other industries, IAB (Integrated Access and Backhaul) for providing nodes for network service area expansion by supporting wireless backhaul links and access links in an integrated manner, mobility enhancement including conditional handover and DAPS (Dual Active Protocol Stack) handover, and two-step random access (NR's 2-step RACH) for simplifying the random access procedure. Standardization is also being conducted on technologies such as the 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software defined network (SDN) technologies, and mobile edge computing (MEC) for receiving services based on UE location.

[0006] If such a 5G mobile communication system is commercialized, the already exponentially growing number of connected devices will be connected to the communication network, and it is therefore expected that enhanced functions and performance of the 5G mobile communication system and integrated operations of the connected devices will be necessary. To this end, new research associated with the following technologies is planned: extended reality (XR) for efficient support of augmented reality (AR), virtual reality (VR), mixed reality (MR), etc., 5G performance improvement and complexity reduction by utilizing artificial intelligence (AI) and machine learning (ML), AI service support, metaverse service support, and drone communication.

[0007] Furthermore, such development of 5G mobile communication systems will serve as a foundation for developing not only new waveforms for ensuring coverage in the terahertz band of 6G mobile communication technology, full-dimensional MIMO (FD-MIMO), multi-antenna transmission technology (such as array antennas and massive antennas), metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional spatial multiplexing technology using orbital angular momentum (OAM), and reconfigurable smart surfaces (RIS), but also full-duplex technology for improving the frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technology for achieving system optimization by utilizing satellites and AI (artificial intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for achieving services of a complex level that exceeds the operating capability limits of UEs by utilizing ultra-high performance communication and computing resources.

[0008] With the development of wireless communication systems as described above, various services can be provided, and thus a method of smoothly providing these services is required. Summary of the invention

[0009] Technical issues

[0010] The embodiments described herein are to provide a method and device for channel state information reporting in a wireless communication system. Specifically, a method and device for a base station and a terminal to efficiently generate, interpret and transmit / receive configuration information for a subband to report channel state information is provided.

[0011] Technical Solutions

[0012] In order to solve the above-mentioned problem, the present disclosure provides a method performed by a terminal in a communication system, the method comprising: receiving a bitmap indicating subbands for channel state information (CSI) reporting from a base station; generating CSI based on one or more subbands for CSI reporting identified based on the bitmap; and transmitting the CSI to the base station, wherein the one or more subbands are identified by using a first method or a second method for identifying one or more subbands by interpreting the bitmap.

[0013] In addition, the present disclosure provides a method performed by a base station in a communication system, the method comprising: transmitting a bitmap indicating subbands for channel state information (CSI) reporting to a terminal, and receiving CSI from the terminal, wherein the CSI is based on one or more subbands for CSI reporting indicated by the bitmap; and identifying the one or more subbands by using a first method or a second method for identifying the one or more subbands by interpreting the bitmap.

[0014] In addition, the present disclosure provides a terminal in a communication system, the terminal including a transceiver and a controller, the controller being configured to perform: control to receive a bitmap indicating subbands for channel state information (CSI) reporting from a base station; generate CSI based on one or more subbands for CSI reporting identified based on the bitmap, and transmit the CSI to the base station, wherein the one or more subbands are identified by using a first method or a second method for identifying one or more subbands by interpreting the bitmap.

[0015] In addition, the present disclosure provides a base station in a communication system, the base station including a transceiver and a controller, the controller being configured to perform: control to transmit a bitmap indicating subbands for channel state information (CSI) reporting to a terminal, and receive CSI from the terminal, wherein the CSI is based on one or more subbands for CSI reporting indicated by the bitmap; and identify the one or more subbands by using a first method or a second method for identifying the one or more subbands by interpreting the bitmap.

[0016] Beneficial Effects

[0017] According to the disclosed embodiments, a communication method and device capable of effectively reporting channel state information in a wireless communication system may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 An example of the basic structure of the time-frequency domain in a 5G communication system is shown.

[0019] Figure 2 An example of a time slot structure used in a 5G communication system is shown.

[0020] Figure 3 An example of bandwidth part (BWP) configuration in a 5G communication system is shown.

[0021] Figure 4 An example of a control resource set for transmitting a downlink control channel in a 5G communication system is shown.

[0022] Figure 5 An example of the structure of a downlink control channel in a 5G communication system is shown.

[0023] Figure 6 An example of an aperiodic CSI reporting method is shown.

[0024] Figure 7 An example of a method of allocating a subband index when reporting subband channel state information according to the present disclosure is shown.

[0025] Figure 8 An example of a method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown.

[0026] Fig. 9 An example of another method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown.

[0027] Fig.10 An example of yet another method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown.

[0028] Fig.11 An example of yet another method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown.

[0029] Fig.12 An example of yet another method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown.

[0030] Fig.13a An example of operations performed by a UE according to an embodiment of the present disclosure is shown.

[0031] Fig.13b An example of operations performed by a base station according to an embodiment of the present disclosure is shown.

[0032] Fig.14is a block diagram showing the structure of a UE according to an embodiment of the present disclosure.

[0033] Fig.15 is a block diagram showing the structure of a base station according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0035] When describing the embodiments, descriptions related to well-known technical contents in the relevant field and not directly related to the present disclosure will be omitted. Such unnecessary omissions are to prevent the main idea of ​​the present disclosure from being obscured and to convey the main idea more clearly.

[0036] 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 each of the accompanying drawings, the same or corresponding elements are given the same reference numerals.

[0037] 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 ways to achieve 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 appended claims. Throughout the specification, the same or similar reference numerals indicate the same or similar elements. In addition, when describing the present disclosure, when it is determined that the description may make the subject matter of the present disclosure unnecessarily unclear, the detailed description of the known functions or configurations incorporated herein will be omitted. The terms to be described below are terms defined in view of the functions in the present disclosure, and may be different according to the user, the user's intention or custom. Therefore, the definition of the term should be made based on the content of the entire specification.

[0038] In the following description, a base station is an entity that allocates resources to a terminal, and may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, and a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, "downlink (DL)" refers to a radio link via which a base station transmits a signal to a terminal, and "uplink (UL)" refers to a radio link via which a terminal transmits a signal to a base station. In addition, in the following description, an LTE or LTE-A system may be described by way of example, but the embodiments of the present disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. Examples of such communication systems may include fifth-generation mobile communication technologies (5G, new radio, and NR) developed after LTE-A, and in the following description, "5G" may be a concept covering existing LTE, LTE-A, and other similar services. In addition, based on the determination of those skilled in the art, the present disclosure may also be applied to other communication systems through some modifications without significantly departing from the scope of the present disclosure.

[0039] Here, it will be understood that each frame of the flowchart diagram and the combination of frames 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 component for realizing the function specified in one or more flowchart frames. These computer program instructions can also be stored in a computer-available or computer-readable memory, which can instruct the computer or other programmable data processing device to operate in a particular manner so that the instructions stored in the computer-available or computer-readable memory produce a manufactured product including an instruction component for realizing the function specified in one or more flowchart frames. The computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on a computer or other programmable device to generate instructions for a computer-implemented process so that the instructions executed on a computer or other programmable device provide steps for realizing the function specified in the flowchart frame.

[0040] In addition, each box in the flowchart diagram may 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 box may not appear in order. For example, two boxes shown in succession may actually be executed substantially simultaneously, or the boxes may sometimes be executed in reverse order, depending on the functions involved.

[0041] As used in the embodiments of the present disclosure, the term "unit" refers to a software element or a hardware element, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and a "unit" can perform certain functions. However, a "unit" does not always have the meaning of being limited to software or hardware. A "unit" can be constructed to be stored in an addressable storage medium or to execute one or more processors. Therefore, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, programs, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" can be combined into a smaller number of elements or "units", or divided into a larger number of elements or "units". In addition, elements and "units" can be implemented as reproducing one or more CPUs in a device or a secure multimedia card. In addition, a "unit" in an embodiment can include one or more processors.

[0042] Wireless communication systems are evolving toward broadband wireless communication systems, which use communication standards such as 3GPP's High Speed ​​Packet Access (HSPA), LTE (Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)), Enhanced LTE (LTE-A), LTE-Pro, 3GPP2's High Speed ​​Packet Data (HRPD), Ultra Mobile Broadband (UMB), IEEE 802.16e, etc. to provide high-speed and high-quality packet data services as well as typical voice-based services.

[0043] As a typical example of a broadband wireless communication system, the LTE system adopts an orthogonal frequency division multiplexing (OFDM) scheme in the downlink (DL) and a single carrier frequency division multiple access (SC-FDMA) scheme in the uplink (UL). The uplink refers to the radio link through which a user equipment (UE) or a mobile station (MS) transmits data or a control signal to a base station (BS) or an eNode B, and the downlink refers to the radio link through which a base station transmits data or a control signal to a UE. The above-mentioned multiple access scheme can separate the data or control information of each user by allocating and operating time-frequency resources for transmitting data or control information to each user, thereby avoiding overlap with each other, that is, thereby establishing orthogonality.

[0044] Since the 5G communication system, which is a post-LTE communication system, must freely reflect the various needs of users, service providers, etc., it is necessary to support services that meet various needs. Services considered in the 5G communication system include enhanced mobile broadband (eMBB) communication, massive machine type communication (mMTC), ultra-reliable low latency communication (URLLC), etc.

[0045] eMBB is designed to provide higher data rates than those supported by existing LTE, LTE-A or LTE-Pro. For example, in a 5G communication system, for a single base station, eMBB must provide a peak data rate of 20Gbps in the downlink and a peak data rate of 10Gbps in the uplink. In addition, the 5G communication system must provide an increased user-perceived data rate as well as a maximum data rate to the UE. In order to meet these requirements, it is necessary to improve the transmission / reception technology including further enhanced multiple-input multiple-output (MIMO) transmission technology. In addition, a frequency bandwidth greater than 20MHz can be used in a frequency band of 3 to 6GHz or 6GHz or higher to obtain the data rate required by the 5G communication system, instead of using a transmission bandwidth of up to 20MHz to transmit signals in the 2GHz band used in LTE.

[0046] In addition, mMTC is being considered to support application services such as the Internet of Things (IoT) in the 5G communication system. mMTC has requirements such as supporting the connection of a large number of UEs in a cell, enhancing the coverage of UEs, improving battery time, reducing the cost of UEs, etc., in order to effectively provide the Internet of Things. Since the Internet of Things provides a communication function while being provided to various sensors and various devices, it must support a large number of UEs in a cell (for example, 1000000 UE / km 2 ). In addition, mMTC-enabled UEs may require wider coverage than other services provided by the 5G communication system because the UEs may be located in shadow areas that are not covered by cells due to the nature of the service, such as basements of buildings. mMTC-enabled UEs must be configured to be inexpensive and may require very long battery life, such as 10 to 15 years, because it is difficult to frequently replace the UE's battery.

[0047] Finally, URLLC is a cellular-based mission-critical wireless communication service. For example, URLLC can be used for services such as remote control of robots or machines, industrial automation, unmanned aerial vehicles, remote healthcare, and emergency alerts. Therefore, URLLC must provide communications with ultra-low latency and ultra-high reliability. For example, URLLC-enabled services must meet an air interface latency of less than 0.5 ms and may also require 10 -5 Or lower packet error rate. Therefore, for services supporting URLLC, the 5G system must provide a shorter transmission time interval (TTI) than other services, and may also require a design for allocating a large amount of resources in the frequency band to ensure the reliability of the communication link.

[0048] The three services in 5G, namely eMBB, URLLC and mMTC, can be multiplexed and transmitted in a single system. In this case, different transmission / reception technologies and transmission / reception parameters can be used between services in order to meet the different requirements of each service. Of course, 5G is not limited to the above three services.

[0049] Hereinafter, the frame structure of the 5G system will be described in more detail with reference to the accompanying drawings.

[0050] Figure 1 An example of the basic structure of the time-frequency domain in a 5G communication system is shown.

[0051] refer to Figure 1 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time domain and the frequency domain is a resource element (RE) 101, which can be defined as one orthogonal frequency division multiplexing (OFDM) symbol 102 along the time axis and one subcarrier 103 along the frequency axis. In the frequency domain, (eg, 12) consecutive REs may constitute one resource block (RB) 104 .

[0052] Figure 2 An example of a time slot structure used in a 5G communication system is shown.

[0053] refer to Figure 2 ,exist Figure 2 An example of the structure of a frame 200, a subframe 201, and a time slot 202 is shown in FIG. One frame 200 may be defined as 10 ms. One subframe 201 may be defined as 1 ms, and thus one frame 200 may include a total of ten subframes 201. One time slot 202 or 203 may be defined as 14 OFDM symbols (i.e., the number of symbols per time slot). ). A subframe 201 may include one or more time slots 202 and 203, and the number of time slots 202 and 203 of each subframe 201 may vary according to the configured value μ of the subcarrier spacing 204 or 205. Figure 2 The example shows the case where μ=0 (2-04) and the case where μ=1 (2-05) are the configuration values ​​of the subcarrier spacing. In the case where μ=0 (204), one subframe 201 may include one time slot 202, and in the case where μ=1 (205), one subframe 201 may include two time slots 203. That is, each subframe The number of time slots in a frame can be different according to the subcarrier spacing configuration value μ, and the number of time slots in each frame is May be different accordingly. and It can be defined according to each subcarrier spacing configuration in Table 1 below.

[0054] Table 1

[0055]

[0056] Next, a bandwidth part (BWP) configuration in a 5G communication system will be described in detail with reference to the accompanying drawings.

[0057] Figure 3 An example of BWP configuration in a 5G communication system is shown.

[0058] refer to Figure 3 , Figure 3 An example is shown where the UE bandwidth 300 is configured to include two bandwidth parts, namely, BWP#1 301 and BWP#2 302. The base station may configure one or more bandwidth parts for the UE, and may configure the following information for each BWP, as given in Table 2 below.

[0059] Table 2

[0060]

[0061]

[0062] Of course, the BWP configuration is not limited to the above examples, and in addition to the above configuration information, various parameters related to the BWP can also be configured for the UE. The base station can transmit the configuration information to the UE through upper layer signaling (e.g., radio resource control (RRC) signaling). One configured BWP or at least one of multiple configured BWPs can be activated. Whether the configured BWP is activated can be semi-statically transmitted from the base station to the UE through RRC signaling or dynamically transmitted through downlink control information (DCI).

[0063] According to an embodiment, before RRC connection, the base station may configure the initial BWP for initial access for the UE through the master information block (MIB). More specifically, the UE may receive configuration information about the control resource set (CORESET) and the search space, which may be used to transmit a PDCCH for receiving system information (which may correspond to the remaining system information (RMSI) or system information block 1 (SIB 1) necessary for initial access through the MIB in the initial access step). Each of the control resource set and the search space configured through the MIB may be considered to correspond to an identifier (ID) 0.

[0064] The base station may notify the UE of configuration information about control resource set #0, such as frequency allocation information, time allocation information, and parameter set, through the MIB. In addition, the base station may notify the UE of configuration information about the monitoring period and timing of control resource set #0, that is, configuration information about search space #0, through the MIB. The UE may consider the frequency domain configured by control resource set #0 obtained from the MIB to be the initial BWP for initial access. In this case, the identification (ID) of the initial BWP may be regarded as 0.

[0065] The UE can receive the physical downlink shared channel (PDSCH) through the configured initial BWP, where the SIB is transmitted through the PDSCH channel. The initial BWP can be used not only to receive SIBs, but also for other system information (OSI), paging, random access, etc.

[0066] The BWP-related configurations supported by the 5G system can be used for various purposes.

[0067] According to an embodiment, if the bandwidth supported by the UE is less than the system bandwidth, this can be supported by BWP configuration. For example, the base station can configure the frequency position of the BWP for the UE so that the UE can transmit / receive data at a specific frequency position within the system bandwidth.

[0068] In addition, according to an embodiment, in order to support different parameter sets, the base station can configure multiple BWPs for the UE. For example, in order to support data transmission / reception of the UE using a subcarrier spacing of 15kHz and a subcarrier spacing of 30kHz, two BWPs can be configured with subcarrier spacings of 15kHz and 30kHz, respectively. Different BWPs can be frequency-division multiplexed (FDM), and if data is to be transmitted / received at a specific subcarrier spacing, the BWP configured with the corresponding subcarrier spacing can be activated.

[0069] In addition, according to an embodiment, in order to reduce the power consumption of the UE, the base station can configure a BWP with bandwidths of different sizes for the UE. For example, if the UE supports a relatively large bandwidth, such as 100 MHz, and always transmits / receives data with the corresponding bandwidth, considerable power consumption may occur. In particular, from the perspective of power consumption, it may be very inefficient to unnecessarily monitor the downlink control channel with a large bandwidth of 100 MHz in the absence of business. In order to reduce the power consumption of the UE, the base station can configure a BWP with a relatively small bandwidth (e.g., a BWP of 20 MHz) for the UE. In the absence of business, the UE can perform monitoring operations in the 20 MHz bandwidth portion, and if data has appeared, it can transmit / receive data with a 100 MHz BWP as instructed by the base station.

[0070] If one or more BWPs are configured for the UE, the base station may indicate to the UE to change the BWP by using the BWP indicator field in the DCI. For example, if the UE's currently activated BWP is Figure 3 If the base station indicates BWP#1 301 in the received DCI, the base station may indicate BWP#2 302 using the BWP indicator in the DCI, and the UE may change the BWP to BWP#2 302 indicated by the BWP indicator in the received DCI.

[0071] Next, a synchronization signal / physical broadcast channel (SS / PBCH) block in a 5G wireless communication system will be described.

[0072] The SS / PBCH block may refer to a physical layer channel block including a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a PBCH. Details thereof may be as follows.

[0073] PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides partial information on the cell ID.

[0074] SSS: Becomes a reference for downlink time / frequency synchronization and provides the remaining cell ID information not provided by PSS. In addition, SSS can be used as a reference signal for PBCH demodulation of PBCH.

[0075] PBCH: MIB that provides mandatory system information necessary for UE to transmit / receive data channels and control channels. The mandatory system information may include search space-related control information indicating radio resource mapping information of the control channel, scheduling control information about a separate data channel for transmitting system information, etc.

[0076] SS / PBCH block: SS / PBCH block includes a combination of PSS, SSS and PBCH. One or more SS / PBCH blocks can be transmitted in a 5ms period, and each transmitted SS / PBCH block can be distinguished by an index.

[0077] The UE may detect the PSS and SSS in the initial access phase and may decode the PBCH. The UE may acquire the MIB from the PBCH and thereby configure the control resource set #0 (which may correspond to the control resource set with the control resource set index 0) for the UE. The UE may monitor the control resource set #0 by assuming that the demodulation reference signal (DMRS) transmitted in the selected SS / PBCH block and the control resource set #0 are quasi-co-located (QCL). The UE may receive system information having downlink control information transmitted in the control resource set #0.

[0078] The UE can obtain configuration information related to the random access channel (RACH) required for initial access from the received system information. Considering the selected SS / PBCH index, the UE can transmit a physical RACH (PRACH) to the base station, and the base station can obtain information about the SS / PBCH block index selected by the UE when receiving the PRACH. The base station can know which block the UE has selected from the various SS / PBCH blocks and the fact that the control resource set #0 associated with it is monitored.

[0079] Next, downlink control information (DCI) in the 5G communication system will be described in detail.

[0080] In the 5G system, scheduling information about uplink data (or PUSCH) or downlink data (or PDSCH) is included in the DCI and transmitted from the base station to the UE through the DCI. Regarding PUSCH or PDSCH, the UE can monitor the fallback DCI format and the non-fallback DCI format. The fallback DCI format may include a fixed field predefined between the base station and the UE, and the non-fallback DCI format may include a configurable field.

[0081] The DCI may be subjected to a channel coding and modulation process and then transmitted through a physical downlink control channel (PDCCH). A cyclic redundancy check (CRC) may be attached to the payload of the DCI message, and the CRC may be scrambled by a radio network temporary identifier (RNTI) corresponding to the identity of the UE. Different RNTIs may be used depending on the purpose of the DCI message (e.g., UE-specific data transmission, power control commands, or random access responses). That is, the RNTI may not be explicitly transmitted, but may be transmitted while being included in the CRC calculation process. When receiving a DCI message transmitted through the PDCCH, the UE may identify the CRC by using the assigned RNTI, and if the CRC identification result is correct, the UE may know that the corresponding message has been transmitted to the UE.

[0082] For example, the DCI for scheduling PDSCH about system information (SI) can be scrambled by SI-RNTI. The DCI for scheduling PDSCH about random access response (RAR) message can be scrambled by RA-RNTI. The DCI for scheduling PDSCH about paging message can be scrambled by P-RNTI. The DCI for notifying the slot format indicator (SFI) can be scrambled by SFI-RNTI. The DCI for notifying transmission power control (TPC) can be scrambled by TPC-RNTI. The DCI for scheduling UE-specific PDSCH or PUSCH can be scrambled by cell RNTI (C-RNTI), modulation and coding scheme C-RNTI (MCS-C-RNTI), or configured scheduling RNTI (CS-RNTI).

[0083] DCI format 0_0 may be used as a fallback DCI for scheduling a PUSCH, and in this case, the CRC may be scrambled by the C-RNTI. For example, DCI format 0_0 in which the CRC is scrambled by the C-RNTI may include the following information.

[0084] Table 3

[0085]

[0086]

[0087] DCI format 0_1 ​​may be used as a non-fallback DCI for scheduling a PUSCH, and in this case, the CRC may be scrambled by the C-RNTI. For example, DCI format 0_1 ​​in which the CRC is scrambled by the C-RNTI may include the following information.

[0088] Table 4

[0089]

[0090]

[0091]

[0092]

[0093]

[0094] DCI format 1_0 may be used as a fallback DCI for scheduling PDSCH, and in this case, the CRC may be scrambled by the C-RNTI. For example, DCI format 1_0 in which the CRC is scrambled by the C-RNTI may include the following information.

[0095] Table 5

[0096]

[0097]

[0098] DCI format 1_1 may be used as a non-fallback DCI for scheduling a PDSCH, and in this case, the CRC may be scrambled by the C-RNTI. For example, DCI format 1_1 in which the CRC is scrambled by the C-RNTI may include the following information.

[0099] Table 6

[0100]

[0101]

[0102]

[0103]

[0104] Hereinafter, a time domain resource allocation method for a data channel in a 5G wireless communication system will be described.

[0105] The base station may configure a table of time domain resource allocation information about PDSCH and PUSCH for the UE through higher layer signaling (e.g., RRC signaling). A table including a maximum of maxNrofDL-Allocations=16 entries may be configured for PDSCH, and a table including a maximum of maxNrofDL-Allocations=16 entries may be configured for PUSCH. In an embodiment, the time domain resource allocation information may include a time slot timing of PDCCH to PDSCH (e.g., a time slot unit time interval between a time point corresponding to receiving the PDCCH and a time point for transmitting the PDSCH scheduled by the received PDCCH; marked as K0), a time slot timing of PDCCH to PUSCH (e.g., a time slot unit time interval between a time point corresponding to receiving the PDCCH and a time point for transmitting the PUSCH scheduled by the received PDCCH; marked as K2), information about the position and length of the start symbol for scheduling PDSCH or PUSCH in a time slot, a mapping type of PDSCH or PUSCH, etc. For example, information such as the following Table 7 or Table 8 may be transmitted from the base station to the UE.

[0106] Table 7

[0107]

[0108]

[0109] Table 8

[0110]

[0111] The base station may notify the UE of one of the entries in the table of the time domain resource allocation information through L1 signaling (e.g., DCI) (e.g., the "time domain resource allocation" field in the DCI may indicate the same entry). The UE may obtain the time domain resource allocation information about the PDSCH or PUSCH based on the DCI obtained from the base station.

[0112] Hereinafter, a frequency domain resource allocation method for a data channel in a 5G wireless communication system will be described.

[0113] The 5G wireless communication system supports two types, such as resource allocation type 0 and resource allocation type 1, as a method for indicating frequency domain resource allocation information of PDSCH and PUSCH.

[0114] Resource Allocation Type 0

[0115] RB allocation information can be notified from the base station to the UE in the form of a bitmap of a resource block group (RBG). RBG can be configured by a set of consecutive virtual RBs (VRBs), and the size P of RBG can be determined based on the value configured via a higher layer parameter (rbg-Size) and the value of the size of BWP defined in the following table.

[0116] Table 9

[0117] Bandwidth portion size Configuration 1 Configuration 2 1-36 2 4 37-72 4 8 73-144 8 16 145-275 16 16

[0118] have The total number of RBGs in bandwidth part i of size (N RBG ) can be defined as follows.

[0119] in

[0120] The size of the first RBG is

[0121] if The size of the last RBG is Otherwise it is P,

[0122] All other RBGs have size P.

[0123] Size is N RBG Each bit of the bitmap of bits may correspond to each RBG. The RBGs may be assigned indices according to a sequence of increasing frequencies starting from the lowest frequency position of the BWP. RBG RBG, RBG#0 to RBG#(N RBG-1) can be mapped from the most significant bit (MSB) to the least significant bit (LSB) of the RBG bitmap. When a specific bit value in the bitmap is 1, the UE can determine that the RBG corresponding to the bit value has been allocated, and when a specific bit value in the bitmap is 0, the UE can determine that the RBG corresponding to the bit value has not been allocated.

[0124] Resource Allocation Type 1

[0125] RB allocation information may be notified from the base station to the UE as information about the start position and length of the consecutively allocated VRBs. At this time, interleaving or non-interleaving may be additionally applied to the consecutively allocated VRBs. The resource allocation field of resource allocation type 1 may be configured by a resource indication value (RIV), which may be determined by the start position of the VRB (RB start ) and the length of the consecutively allocated RBs (L RB ) configuration. More specifically, having The RIV within a BWP of size can be defined as follows.

[0126] if So

[0127]

[0128] otherwise

[0129]

[0130] Where L RB ≥1 and no more than

[0131] The base station may configure the resource allocation type for the UE via higher layer signaling to the UE (for example, the higher layer parameter resourceAllocation may be configured to have one of resourceAllocationType0, resourceAllocationType1, and dynamicSwitch.). In the case where the UE is configured with both resource allocation types 0 and 1 (or in the same manner, the higher layer parameter resourceAllocation is configured with dynamicSwitch), the base station may use the bit corresponding to the MSB in the field indicating resource allocation in the DCI format indicating scheduling to indicate whether the resource allocation type is resource allocation type 0 or resource allocation type 1. In addition, based on the indicated resource allocation type, resource allocation information may be indicated by the remaining bits except the bit corresponding to the MSB, and the UE may interpret the resource allocation field information of the DCI field based on the indicated resource allocation information. In the case where the UE is configured with one of resource allocation type 0 and resource allocation type 1 (or in the same manner, the higher layer parameter resourceAllocation is configured to have a value of resourceAllocation type0 and resourceAllocationtype 1), resource allocation information may be indicated based on the resource allocation type of the field indicating resource allocation in the DCI format indicating scheduling configured, and the UE may interpret the resource allocation field information of the DCI field based on the indicated resource allocation information.

[0132] Hereinafter, a downlink control channel in a 5G communication system will be described in more detail with reference to the accompanying drawings.

[0133] Figure 4 An example of a control resource set for transmitting a downlink control channel in a 5G communication system is shown.

[0134] refer to Figure 4 , a UE BWP 410 may be configured along the frequency axis, and two control resource sets (control resource set #1 401 and control resource set #2 402) may be configured within a time slot 420 along the time axis. The control resource sets 401 and 402 may be configured in specific frequency resources 403 within the entire UE BWP 420 along the frequency axis. The control resource sets 401 and 402 may each be configured as one or more OFDM symbols along the time domain, and the number of OFDM symbols may be defined as a control resource set duration 404. Reference Figure 4In the example shown, control resource set #1 401 is configured to have a control resource set duration corresponding to two symbols, and control resource set #2 402 is configured to have a control resource set duration corresponding to one symbol.

[0135] The control resource set in 5G as described above can be configured for the UE by the base station through higher layer signaling (e.g., SI, MIB, RRC signaling, etc.). The description of configuring the control resource set for the UE means providing information such as the control resource set identifier, the frequency location of the control resource set, and the symbol duration of the control resource set. For example, the information may include the following information given in Table 10 below.

[0136] Table 10

[0137]

[0138]

[0139] In Table 10, the tci-StatesPDCCH (abbreviated as transmission configuration indication (TCI) state) configuration information may include information of one or more SS / PBCH block indices or channel state information reference signal (CSI-RS) indices, which are quasi-co-located (OCLed) with the DMRS transmitted in the corresponding CORESET.

[0140] Figure 6 An example of the structure of a downlink control channel in a 5G wireless communication system is shown.

[0141] according to Figure 5 , the basic unit of time and frequency resources constituting the control channel may be referred to as a resource element group (REG) 503, and the REG 503 may be defined by one OFDM symbol %n along the time axis and one physical resource block (PRB) 502 (i.e., 12 subcarriers) along the frequency axis. The base station may configure the downlink control channel allocation unit by connecting the REG 503.

[0142] Assume that the basic unit of downlink control channel allocation in 5G is as follows Figure 5 As shown in FIG. 5A , a CCE 504 may include multiple REGs 503. Figure 5For example, REG 503 may include 12 REs, and if one CCE 504 includes 6 REGs 503, one CCE 504 may include 72 REs. Once a downlink control resource set is configured, it may include multiple CCEs 504, and a specific downlink control channel may be mapped to one or more CCEs 504 and then transmitted according to an aggregation level (AL) in the control resource set. CCEs 504 in the control resource set are distinguished by number, and the number of CCEs 504 may be allocated according to a logical mapping scheme.

[0143] Figure 5 The basic unit of the downlink control channel shown (ie, REG 503) may include an RE to which the DCI is mapped and an area to which a reference signal (DMRS 505) for decoding the RE is mapped. Figure 5 As shown, three DRMSs 503 can be transmitted in one REG 505. Depending on the aggregation level (AL), the number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16, and different numbers of CCEs can be used to achieve link adaptation of the downlink control channel. For example, in the case of AL=L, one downlink control channel can be transmitted through L CCEs.

[0144] The UE needs to detect the signal when there is no information about the downlink control channel, so a search space indicating a set of CCEs has been defined for blind decoding. A search space is a set of downlink control channel candidates, including CCEs that the UE needs to try to decode at a given AL, and since 1, 2, 4, 8 or 16 CCEs can form a bundle at various ALs, the UE can have multiple search spaces. A search space set can be defined as a set of search spaces at all configured aggregation levels.

[0145] The search space can be divided into a common search space and a UE-specific search space. A group of UEs or all UEs can search the common search space of the PDCCH in order to receive cell common control information, such as dynamic scheduling of system information or paging messages. For example, PDSCH scheduling allocation information for transmitting SIBs including cell operator information, etc. can be received by searching the common search space of the PDCCH. In the case of a common search space, a group of UEs or all UEs need to receive the PDCCH, and therefore the common search space can be defined as a predefined set of CCEs. Scheduling allocation information about UE-specific PDSCH or PUSCH can be received by searching the UE-specific search space of the PDCCH. The UE-specific search space can be defined UE-specifically as a function of various system parameters and UE identification.

[0146] In the 5G system, the parameters of the search space for PDCCH can be configured by the base station for the UE through higher layer signaling. For example, the base station can provide the UE with configurations such as the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the monitoring timing for each symbol in the time slot for the search space, the search space type (common search space or UE-specific search space), the combination of RNTI and DCI format to be monitored in the corresponding search space, and the control resource set index for monitoring the search space. For example, the parameters of the search space for PDCCH may include the following information given in Table 11 below.

[0147] Table 11

[0148]

[0149]

[0150]

[0151] According to the configuration information, the base station may configure one or more search space sets for the UE. According to an embodiment, the base station may configure search space set 1 and search space set 2 for the UE, may configure DCI format A scrambled by X-RNTI to be monitored in a common search space in search space set 1, and may configure DCI format B scrambled by Y-RNTI to be monitored in a UE-specific search space in search space set 2.

[0152] According to the configuration information, one or more search space sets may exist in a common search space or a UE-specific search space. For example, search space set #1 and search space set #2 may be configured as common search spaces, while search space set #3 and search space set #4 may be configured as UE-specific search spaces.

[0153] The combinations of DCI formats and RNTIs given below may be monitored in the common search space. Obviously, the examples given below are not limiting.

[0154] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, MCS-C-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0155] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0156] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0157] -DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0158] -DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0159] The combinations of DCI formats and RNTIs given below may be monitored in the UE-specific search space. Obviously, the examples given below are not limiting.

[0160] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0161] - The RNTI listed in DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI may follow the definition and usage given below.

[0162] C-RNTI: used to schedule UE-specific PDSCH

[0163] MCS-C-RNTI: used to schedule UE-specific PDSCH

[0164] Temporary Cell RNTI (TC-RNTI): used to schedule UE-specific PDSCH

[0165] CS-RNTI: used to schedule UE-specific PDSCH with semi-static configuration

[0166] RA-RNTI: used to schedule PDSCH in the random access step

[0167] P-RNTI: used to schedule the PDSCH in which paging is transmitted

[0168] SI-RNTI: used to schedule the PDSCH in which system information is transmitted

[0169] Interrupt RNTI (INT-RNTI): used to indicate whether PDSCH is punctured

[0170] Transmit Power Control for PUSCH RNTI (TPC-PUSCH-RNTI): used to indicate the power control command for PUSCH

[0171] Transmit Power Control Command for PUCCH RNTI (TPC-PUCCH-RNTI): used to indicate the power control command for PUCCH

[0172] Transmit Power Control for SRS RNTI (TPC-SRS-RNTI): used to indicate power control commands for SRS

[0173] The DCI formats listed above may follow the definitions given below.

[0174] Table 12

[0175]

[0176] In a 5G wireless communication system, a search space at an aggregation level L combining CORESET p and a search space set s may be represented by the following Equation 1.

[0177] Equation 1

[0178]

[0179] -L: aggregation level

[0180] -n CI : Carrier index

[0181] -N CCE,p : Controls the total number of CCEs in resource set p

[0182] - Time slot index

[0183] - Number of PDCCH candidates at aggregation level L

[0184] - PDCCH candidate index at aggregation level L

[0185] -i=0,…,L-1

[0186] - Y p,-1 =n RNTI ≠0, A p =39827for pmod3=0,A p =39829 for pmod3=1, A p =39839for pmod3=2,D=65537

[0187] -n RNTI :UE ID

[0188] In the case of a public search space, The value may correspond to 0.

[0189] In the case of a UE-specific search space, The value may correspond to a value changed by the UE's identity (C-RNTI or ID configured by the base station for the UE) and the time index.

[0190] [CSI Framework]

[0191] In the NR system, there is a CSI framework for indicating the measurement and reporting of channel state information (CSI) by the base station to the UE. The CSI framework of NR can be configured by at least two elements including resource settings and report settings. By referring to at least one ID of the resource setting, the report setting can have a connection relationship with the resource setting.

[0192] According to an embodiment of the present disclosure, a resource setting may include information related to a reference signal used by a UE to measure channel state information. A base station may configure at least one resource setting for a UE. For example, a base station and a UE may transmit and receive signaling information as described in Table 13 below to convey information related to a resource setting.

[0193] Table 13

[0194]

[0195]

[0196] In Table 13, the signaling CSI-ResourceConfig may include information related to each resource setting. Each CSI-ResourceConfig may include S (≥1) CSI resource sets (given by the higher layer parameter csi-RS-ResourceSetList). Each CSI resource set may be located in a DL BWP identified by the higher layer parameter bwp-id, and the resource setting may be connected to the reporting setting of the same downlink BWP.

[0197] According to the signaling information, each resource setting may include a resource setting index (csi-ResourceConfigId), a BWP index (bwp-ID), a time domain transmission configuration of the resource (resourceType), or a resource set list (csi-RS-ResourceSetList) including at least one resource set. The time domain transmission configuration of the resource can be configured as aperiodic transmission, semi-persistent transmission, or periodic transmission. Regarding periodic or semi-persistent CSI resource settings, the number of CSI-RS resource sets can be limited to S=1, and the configured period and time slot offset can be given as a parameter set of the DL BWP identified by the bwp-id.

[0198] The resource set list may 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, and the at least one resource may correspond to a CSI reference signal (CSI-RS) resource or an index of an SS / PBCH block. 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)).

[0199] For example, when a resource set includes a CSI-RS, the base station and the UE may transmit and receive signaling information as shown in the following Table 14 to convey information related to the resource set.

[0200] Table 14

[0201]

[0202] In Table 14, the signaling information NZP-CSI-RS-ResourceSet includes information related to each resource set. According to the signaling information, each resource set may include at least information related to a resource set index (nzp-CSI-ResourceSetId) or a CSI-RS index set (nzp-CSI-RS-Resources). In addition, each resource set may include a portion of information related to a spatial domain transmission filter of a CSI-RS resource (repetition), or information related to whether a CSI-RS resource has a tracking purpose (trs-Info).

[0203] CSI-RS may be the most representative reference signal included in a resource set. The base station and the UE may transmit and receive signaling information as shown in Table 15 below to convey information related to CSI-RS resources.

[0204] Table 15

[0205]

[0206] In Table 15, the signaling information NZP-CSI-RS-Resource includes information related to each CSI-RS. The information included in the signaling information NZP-CSI-RS-Resource may have the following meanings.

[0207] -nzp-CSI-RS-ResourceId: CSI-RS resource index

[0208] -resourceMapping: Resource mapping information of CSI-RS resources

[0209] -powerControlOffset: The ratio between the energy per RE (EPRE) of PDSCH and the CSI-RS EPRE

[0210] -powerControlOffsetSS: Ratio between SS / PBCH block EPRE and CSI-RS EPRE

[0211] -scramblingID: scrambling index of the CSI-RS sequence

[0212] -periodicityAndOffset: transmission period and time slot offset of CSI-RS resources

[0213] -qcl-InfoPeriodicCSI-RS: TCI state information when the corresponding CSI-RS is a periodic CSI-RS.

[0214] The resourceMapping included in the signaling NZP-CSI-RS-Resource may indicate resource mapping information of the CSI-RS resource, and may include RE mapping of frequency resources, the number of antenna ports, symbol mapping, code division multiplexing (CDM) type, frequency resource density, and band mapping information. The number of ports (port), frequency resource density (densiy), CDM type (type), and time-frequency domain RE mapping that can be configured by the resource mapping information may have a value determined in one of the rows (row) shown in Table 16.

[0215] Table 16

[0216]

[0217] Table 16 shows the frequency domain and time domain starting positions according to the number of CSI-RS ports (X), CDM type, and CSI-RS component RE pattern. And the frequency resource density that can be configured by the number of frequency domain REs (k') and the number of time domain REs (l') of the CSI-RS component RE pattern. The above CSI-RS component RE pattern can be a basic unit for configuring CSI-RS resources. The CSI-RS component RE pattern can be configured by YZ REs through Y=1+max(k') frequency domain REs and Z=1+max(l') time domain REs.

[0218] When the number of CSI-RS ports is 1, the position of the CSI-RS RE can be specified in the PRB without limiting the subcarrier, and 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 position of the CSI-RS RE can be specified at every two subcarriers in the PRB, and can be specified by a 6-bit bitmap. When the number of CSI-RS ports is 4 and Y=4, the position of the CSI-RS RE can be specified at every four subcarriers in the PRB, and can be specified by a 3-bit bitmap. Similarly, the position of the time domain RE can be specified by a total of 14 bits of bitmap. Here, according to the Z value shown in Table 25, the length of the bitmap can be changed like the frequency position specification. However, the principle of the change is similar to the above description, and therefore, the repeated description will be omitted below.

[0219] According to an embodiment of the present disclosure, by referring to at least one ID of a resource setting, report settings may have an association relationship with each other, and the resource setting having an association relationship with the report setting provides configuration information including information about a reference signal for measuring channel information. When the resource setting having an association relationship with the report setting is used to measure channel information, the measured channel information may be used to report the channel information according to a reporting method configured in the report setting having an association relationship.

[0220] According to an embodiment of the present disclosure, the report setting may include configuration information related to the CSI reporting method. For example, the base station and the UE may transmit and receive signaling information as shown in Table 17 to convey information about the report setting.

[0221] Table 17

[0222]

[0223]

[0224]

[0225]

[0226] In Table 17, 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] -reportConfigId: Report setting index

[0228] -carrier: serving cell index

[0229] -resourcesForChannelMeasurement: Index of the resource settings for channel measurement associated with the report settings

[0230] -csi-IM-ResourcesForInterference: Resource setting index of CSI-IM resources for interference measurement associated with the reporting setting

[0231] -nzp-CSI-RS-ResourcesForInterference: Resource setting index of CSI-RS resources for interference measurement associated with the reporting setting

[0232] -reportConfigType: indicates the time domain transmission setting and transmission channel of the channel report, and can have aperiodic transmission, semi-persistent PUCCH transmission, semi-persistent PUSCH transmission, or periodic transmission setting.

[0233] -reportQuantity: indicates the type of channel information to be reported, and may have the type of channel information when a channel report is not transmitted ("none") and when a channel report is transmitted ("cri-RI-PMI-CQI", "cri-RI-i1", "cri-RI-i1-CQI", "cri-RI-CQI", "cri-RSRP", "ssb-Index-RSRP", and "cri-RI-LI-PMI-CQI"). Here, the elements included in the type of channel information refer to a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), and / or a layer 1 reference signal received power (L1-RSRP).

[0234] -reportFreqConfiguration: indicates whether the channel information to be reported includes only information about the full frequency band (wideband) or information about each subband. In the case where the channel information includes information about each subband, configuration information about the subband including the channel information may be included.

[0235] -timeRestrictionForChannelMeasurements: Whether there is a time domain restriction on the reference signal for channel measurement in the reference signal referenced by the channel information to be reported.

[0236] -timeRestrictionforinterferencemmeasurements: Whether there is a time domain restriction on the reference signal used for interference measurement in the reference signal referenced by the channel information to be reported.

[0237] -codebookConfig: The codebook information referenced by the channel information to be reported

[0238] -groupBasedBeamReporting: Whether beam grouping for channel reporting occurs

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

[0240] -subbandSize: Index indicating the subband size of the channel information

[0241] -non-PMI-PortIndication: Port mapping information to be referenced when reporting non-PMI channel information.

[0242] When the base station instructs to perform channel information reporting via higher layer signaling or L1 signaling, the UE can perform channel information reporting by referring to the above configuration information included in the indicated reporting setting.

[0243] The base station may direct the UE to perform CSI reporting via RRC signaling or higher layer signaling including medium access control (MAC) control element (CE) signaling or L1 signaling (eg, common DCI, group common DCI, UE-specific DCI).

[0244] For example, the base station may provide an indication of an aperiodic channel information report (CSI report) to the UE via higher layer signaling or DCI using DCI format 0_1. The base station configures parameters for aperiodic CSI reporting for the UE or multiple CSI report triggering states including parameters for CSI reporting via higher layer signaling. The parameters for CSI reporting or CSI report triggering states may include a set including a time slot interval or a possible time slot interval between a PDCCH including DCI and a PUSCH including a CSI report, a reference signal ID for channel state measurement, and the type of channel information to be included.

[0245] When the base station provides an indication of some of the multiple CSI report triggering states to the UE through DCI, the UE reports channel information according to the CSI report setting of the report setting configured in the indicated CSI report triggering state. The aperiodic CSI report can be triggered by the CSI request field of the aforementioned DCI format 0_1, which corresponds to the scheduling DCI of the PUSCH. The CSI request indicator can be configured as N TS (=0, 1, 2, 3, 4, 5 or 6) bits and may be determined by higher layer signaling (reportTriggerSize). Among one or more aperiodic CSI report triggering states that may be configured by higher layer signaling (CSI-AperiodicTriggerStateList), one triggering state may be triggered by a CSI request indicator.

[0246] - When all bits of the CSI request field are 0, this may mean that no CSI report is requested.

[0247] -When the number of CSI trigger states (M) in the configured CSI-AperiodicTriggerStateLite is greater than 2 NTs -1, M CSI trigger states can be mapped to 2 according to the predefined mapping relationship. NTs -1, and 2 NTs - One of 1 CSI triggering states may be indicated by the CSI request field.

[0248] -When the number of CSI trigger states (M) in the configured CSI-AperiodicTriggerStateLite is equal to or less than 2 NTs When -1, one of the M CSI triggering states may be indicated by the CSI request field.

[0249] Table 18 below shows an example of a relationship between a CSI request indicator and a CSI triggering state that may be indicated by the indicator.

[0250] Table 18

[0251]

[0252] Channel information reporting can be performed through the PUSCH scheduled by DCI format 0_1. When a bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 ​​indicates "1", the uplink data (UL-SCH) and the acquired CSI can be multiplexed and transmitted to the PUSCH resources scheduled by DCI format 0_1. When a bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 ​​indicates "0", only CSI without uplink data (UL-SCH) can be mapped and transmitted to the PUSCH resources scheduled by DCI format 0_1. The time domain resource allocation of the PUSCH including the CSI report of the UE can be performed by indicating the time slot interval between the PDCCH and the PUSCH indicated by the DCI, the starting symbol and symbol length within the time slot for the time domain resource allocation of the PUSCH, etc. For example, the position of the time slot in which the PUSCH including the CSI report of the UE is transmitted can be indicated by the time slot interval between the PDCCH and the PUSCH indicated by the DCI, and the start symbol and symbol length within the time slot can be indicated via the time domain resource allocation field of the above DCI. The period and time slot offset of the PUSCH resource used to transmit the CSI can be given based on the parameter set of the UL BWP configured to transmit the CSI report.

[0253] For example, the base station may provide an indication to the UE of semi-persistent CSI reporting transmitted to PUSCH via DCI using DCI format 0_1. The base station may activate or deactivate semi-persistent CSI reporting transmitted to PUSCH via DCI scrambled by SP-CSI-RNTI. When semi-persistent CSI reporting is activated, the UE may periodically report channel information according to the configured timeslot interval. When semi-persistent CSI reporting is deactivated, the UE may stop periodic channel information reporting that has been activated.

[0254] The base station configures parameters for semi-persistent CSI reporting of the UE or multiple CSI report triggering states including parameters for semi-persistent CSI reporting via higher layer signaling. The parameters for CSI reporting or CSI report triggering states may include a set including a time slot interval or a possible time slot interval between a PDCCH including a DCI indicating a CSI report and a PUSCH including a CSI report, a time slot interval between a time slot in which higher layer signaling indicating a CSI report is activated and a PUSCH including a CSI report, a time slot interval period of the CSI report, and a type of channel information included.

[0255] When the base station activates some of the multiple CSI report trigger states or some of the multiple report settings to the UE via higher layer signaling or DCI, the UE can report channel information according to the report setting included in the indicated CSI report trigger state or the CSI report setting configured in the activated report setting. Channel information reporting can be performed by the PUSCH semi-persistently scheduled by the DCI format 0_1 ​​scrambled by SP-CSI-RNTI. The time domain resource allocation of the PUSCH including the UE's CSI report can be performed by indicating the following: the time slot interval period of the CSI report, the time slot interval between the time slot in which the higher layer signaling is activated and the PUSCH, the time slot interval between the PDCCH and the PUSCH indicated by the DCI, the start symbol and symbol length within the time slot for the time domain resource allocation of the PUSCH, etc. For example, the position of the time slot for transmitting the PUSCH including the UE's CSI report can be indicated by the time slot interval between the PDCCH and the PUSCH indicated by the DCI, and the start symbol and symbol length within the time slot can be indicated via the time domain resource allocation field of the above-mentioned DCI format 0_1.

[0256] For example, the base station may provide the UE with an indication of semi-persistent CSI reporting transmitted to the PUCCH via higher layer signaling such as MAC-CE. Through MAC-CE signaling, the base station may activate or deactivate semi-persistent CSI reporting transmitted to the PUCCH. When semi-persistent CSI reporting is activated, the UE may periodically report channel information according to the configured time slot interval. When semi-persistent CSI reporting is deactivated, the UE may stop periodically reporting channel information that has been activated.

[0257] The base station configures parameters for the semi-persistent CSI report of the UE through higher layer signaling. The parameters for CSI reporting may include the PUCCH resources through which the CSI report is transmitted, the time slot interval period of the CSI report, and the type of channel information included. The UE may transmit the CSI report through the PUCCH. Alternatively, when the PUCCH for CSI reporting overlaps with the PUSCH, the UE may transmit the CSI report to the PUSCH. The position of the time slot in which the PUCCH including the CSI report is transmitted may be indicated by the time slot interval period of the CSI report configured via higher layer signaling, and the time slot interval between the time slot in which the higher layer signaling is activated and the PUCCH including the CSI report, as well as the starting symbol and symbol length within the time slot may be indicated via the starting symbol and symbol length, and the PUCCH resources configured via higher layer signaling are allocated to the starting symbol. The period and time slot offset of the PUCCH or PUSCH resources for transmitting CSI may be given based on the parameter set of the UL BWP configured for transmitting the CSI report.

[0258] For example, the base station may provide an indication of periodic CSI reporting to the UE via higher layer signaling. The base station may activate or deactivate periodic CSI reporting via higher layer signaling including RRC signaling. When periodic CSI reporting is activated, the UE may periodically report channel information according to the configured time slot interval. When periodic CSI reporting is deactivated, the UE may stop periodically reporting the activated channel information.

[0259] The base station configures the report settings including parameters for periodic CSI reporting of the UE via higher layer signaling. The parameters for CSI reporting may include PUCCH resource configuration for CSI reporting, the time slot interval between the time slot in which the higher layer signaling indicating the CSI report is activated and the PUCCH including the CSI report, the time slot interval period of the CSI report, the reference signal ID for channel state measurement, and the type of channel information included. The UE may transmit the CSI report via the PUCCH. Alternatively, when the PUCCH for CSI reporting overlaps with the PUSCH, the UE may transmit the CSI report to the PUSCH. The position of the time slot in which the PUCCH including the CSI report is transmitted may be indicated by the time slot interval period of the CSI report configured via higher layer signaling and 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 within the time slot may be indicated by the starting symbol and symbol length, and the PUCCH resources configured via higher layer signaling are allocated to the starting symbol. The periodicity and slot offset of the PUCCH resources used to transmit CSI may be given based on the parameter set of the UL BWP configured for transmitting the CSI report.

[0260] When the base station provides an indication of non-periodic CSI reporting or semi-persistent CSI reporting to the UE through DCI, the UE can determine whether the UE can perform effective channel reporting through the indicated CSI reporting by considering the channel calculation time required for the CSI reporting (CSI calculation time).

[0261] For aperiodic CSI reporting or semi-persistent CSI reporting indicated by DCI, the UE may report a valid CSI report starting from an uplink symbol after the Z symbol after the last symbol included in the PDCCH including the DCI indicating that the CSI report has ended. The above-mentioned Z symbol may be different according to the parameter set of the downlink BWP corresponding to the PDCCH including the DCI indicating the CSI report, the parameter set of the uplink BWP corresponding to the PUSCH transmitting the CSI report, and the type or characteristics of the channel information reported by the CSI report (reporting amount, frequency band granularity, number of ports of the reference signal, codebook type, etc.).

[0262] In other words, in order for a CSI report to be determined as a valid CSI report (if the CSI report is a valid CSI report), the uplink transmission of the CSI report should not occur at Z ref symbol, including timing advance. In this case, Z ref The symbol is an uplink symbol, where the cyclic prefix (CP) is at time T from the moment when the last symbol triggering the PDCCH has ended. proc，CST =(Z)(2048+144)·κ2 -μ ·T c Here, the detailed value of Z follows the explanation below, T c =1 / (Δf max ·N f ), N f =4096, κ=64, and μ is a parameter set. At this time, we can commit μ to use (μ PDCCB , μ CSI-RS , μ UL ) is the largest T proc,CSI Value, where μ PDCCH It can refer to the subcarrier spacing used for PDCCH transmission, μ CSI-RS may refer to the subcarrier spacing used for CSI-RS transmission, and μ UL It can refer to the subcarrier spacing of the uplink channel used for uplink control information (UCI) transmission of CSI reporting. For another example, it can be committed to use μ, where μ refers to (μ PDCCH , μ UL ) is the largest T proc,CSI Value. About μ PDCCH and μ UL For the definition of , see the above description. For the convenience of future explanation, satisfying the above conditions will be referred to as satisfying CSI report validity condition 1.

[0263] In addition, when the reference signal for channel measurement for non-periodic CSI reporting indicated to the UE through DCI is a non-periodic reference signal, the UE may report a valid CSI report starting from the uplink symbol after the Z' symbol after the last symbol including the reference signal has ended. The above-mentioned Z' symbol may be based on a parameter set of a downlink BWP corresponding to the PDCCH including the DCI indicating the CSI report, a parameter set of a bandwidth corresponding to the reference signal for channel measurement for the CSI report, a parameter set of an uplink BWP corresponding to the PUSCH for transmitting the CSI report, and a type or characteristic of the channel information reported by the CSI report (reporting amount, frequency band granularity, number of ports of the reference signal, codebook type, etc.).

[0264] In other words, in order for a CSI report to be determined as a valid CSI report (if the CSI report is a valid CSI report), the uplink transmission of the CSI report should not occur at Z ref’ symbol, including timing advance. In this case, Z ref’ A symbol is an uplink symbol, where the CP is at time T′ from the moment when the last symbol of the aperiodic CSI-RS or aperiodic CSI-IM triggered by the triggering PDCCH has ended. proc，CST =(Z′)(2048+144)·κ2 -μ ·T c Here, the detailed value of Z' follows the explanation below, T c =1 / (Δf max ·N f ), Δf=480·103Hz, N f =4096, κ=64, and μ is a parameter set. At this time, we can commit μ to use (μ PDCCH , μ CSI-RS , μ UL) The largest T proc,CSI Value, where μ PDCCH It can refer to the subcarrier spacing used for PDCCH transmission, μ CSI-RS It can refer to the subcarrier spacing used for CSI-RS transmission, and μ UL It can refer to the subcarrier spacing of the uplink channel used for uplink control information (UCI) transmission of CSI reporting. For another example, it can be committed to use μ, where μ refers to (μ PDCCH , μ UL ) is the largest T proc,CSI Value. About μ PDCCH and μ UL For the definition of , see the above description. For the convenience of future explanation, satisfying the above condition will be referred to as satisfying CSI report validity condition 2.

[0265] When the base station provides the UE with an indication of aperiodic CSI reporting for an aperiodic reference signal through DCI, the UE can perform valid CSI reporting starting from the first uplink symbol, which satisfies the time point after the Z symbol after the last symbol in the PDCCH including the DCI indicating the CSI report has ended, and the time point after the Z' symbol after the last symbol of the reference signal has ended. That is, in the case of aperiodic CSI reporting based on aperiodic reference signals, both CSI report validity conditions 1 and 2 should be met to be considered as a valid CSI report.

[0266] When the CSI reporting time point indicated by the base station does not meet the CSI calculation time requirement, the UE may determine that the CSI report is invalid and does not consider updating the channel information state of the CSI report.

[0267] The Z and Z' symbols used to calculate the above CSI calculation time follow the following Tables 28 and 29. For example, when the channel information reported in the CSI report includes only wideband information, the number of reference signal ports is equal to or less than 4, the reference signal resource is 1, the codebook type is "typeI-SinglePanel", or the reported channel information type (reporting amount) is "cri-RI-CQI", the Z and Z' symbols follow the Z in Table 29. 1 and Z 1’ In the following, this will be named as delay requirement 2. In addition, when the PUSCH including the CSI report does not include a transport block (TB) or a hybrid automatic repeat request acknowledgement (HARQ-ACK) and the CPU occupancy of the UE is 0, the Z and Z' symbols follow the Z in Table 19 1 and Z 1’ The value of , and this will be named Delay Requirement 1. The CPU occupancy described above is described in detail below. In addition, when the reporting quantity is "cri-RSRP" or "ssb-Index-RSRP", the Z and Z' signs follow the Z in Table 20. 3 and Z 3’ X1, X2, X3, and X4 in Table 20 refer to the UE capability for beam reporting time. B1 and K B2 Refers to the UE capability for beam switching time. When the Z and Z' symbols do not correspond to the type or characteristics of the channel information reported in the above CSI report, the Z and Z' symbols shall follow the Z in Table 20 2 and Z 2’ The value of .

[0268] Table 19

[0269]

[0270] Table 20

[0271]

[0272] When providing an indication of a non-periodic, semi-persistent, or periodic CSI report to the UE, the base station may configure CSI reference resources to determine reference time and frequency resources for the channel to be reported in the CSI report. The frequency of the CSI reference resources may be carrier and subband information to measure the CSI indicated by the CSI report settings, which may correspond to the carrier and report frequency configuration (reportFreqConfiguration) of Table 26, respectively. The timing of the CSI reference resources may be defined based on the time at which the CSI report is transmitted. For example, when CSI report #X is indicated to be transmitted via uplink time slot n' of the carrier and BWP in which the CSI report is to be transmitted, the timing of the CSI reference resources for CSI report #X may be defined as the downlink time slot nn of the carrier and BWP in which the CSI is measured. CSI-ref When the parameter set of carrier and BWP used to measure CSI is named μ DL , and when the parameter set for the carrier and BWP used to transmit CSI report #X is named μ UL When the downlink time slot n is calculated as In the case where the CSI report #X transmitted in uplink slot n' is a semi-persistent or periodic CSI report, when a single CSI-RS / SSB resource is connected to the CSI report according to the number of CSI-RS / SSB resources used for channel measurement, the slot interval n between the downlink slot n and the CSI reference signal CSI-ref follow And when multiple CSI-RS / SSB resources are connected to the CSI report, the time slot interval is n CSI-ref follow When the CSI report #X transmitted from uplink time slot n' is an aperiodic CSI report, by considering the CSI calculation time Z', n for channel measurement CSI-ref is calculated as Above is the number of symbols included in one slot, and it is assumed that in NR

[0273] When the base station instructs the UE to transmit a predefined CSI report in uplink time slot n' via higher layer signaling or DCI, the UE can report the CSI by performing channel measurement or interference measurement on the CSI-RS resources, CSI-IM resources or SSB resources, where the CSI-RS resources, CSI-IM resources or SSB resources are transmitted no later than the CSI reference resource time slot of the CSI report transmitted from the uplink time slot n' of the CSI-RS resources, CSI-IM resources or SSB resources associated with the corresponding CSI report. The CSI-RS resource, CSI-IM resource, or SSB resource associated with the corresponding CSI report may refer to a CSI-RS resource, CSI-IM resource, or SSB resource included in a resource set configured in a resource setting referenced by a report setting of a CSI report of a UE configured via higher layer signaling, a CSI-RS resource, CSI-IM resource, or SSB resource referenced by a CSI report trigger state including a parameter for a corresponding CSI report, or a CSI-RS resource, CSI-IM resource, or SSB resource indicated by an ID of a reference signal (RS) set.

[0274] In an embodiment of the present disclosure, CSI-RS, CSI-IM and SSB timing refer to the transmission time point of CSI-RS, CSI-IM and SSB resources determined by a higher layer configuration or a combination of a higher layer configuration and a DCI trigger. In the example, in the case of a semi-persistent or periodic CSI-RS resource, the time slot to be transmitted is determined according to the time slot period and time slot offset configured by higher layer signaling, and the transmission symbol within the time slot is determined according to one of the resource mapping methods within the time slot of reference Table 25 according to the resource mapping information (resourceMapping). In another example, in the case of a non-periodic CSI-RS resource, the time slot to be transmitted is determined according to the time slot offset of the PDCCH having a DCI reported by an indication channel configured by higher layer signaling, and the transmission symbol within the time slot is determined according to one of the resource mapping methods of reference Table 25 according to the resource mapping information (resourceMapping).

[0275] The above-mentioned CSI-RS timing can be determined by independently considering the transmission time point of each CSI-RS resource or by comprehensively considering the transmission time point of one or more CSI-RS resources included in the resource set, and therefore, according to each resource set configuration, for the CSI-RS timing, the following two interpretations are possible.

[0276] -Explanation 1-1: From the start time point of the earliest symbol to the end time point of the latest symbol, a 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 the CSI report in the earliest symbol is transmitted

[0277] - Interpretation 1-2: From the start time point of the earliest symbol to the end time point of the latest symbol, the CSI-RS resource transmitted at the earliest time point in the earliest symbol is transmitted, and the CSI-RS resource transmitted at the latest time point in the latest symbol (which includes one or more CSI-RS resources in the resource set configured in the resource setting referenced by the report setting configured for the CSI report) is transmitted

[0278] In the following embodiments of the present disclosure, two interpretations of CSI-RS timing may be considered and applied separately. In addition, in the case of CSI-IM timing and SSB timing, it is possible to consider two interpretations, such as CSI-RS timing, but since the principle is similar to the above description, redundant descriptions will be omitted below.

[0279] In an embodiment of the present disclosure, among the CSI-RS resources, CSI-IM resources, and SSB resources included in the resource set configured in the resource setting referenced by the report setting configured for CSI report #X, “CSI-RS, CSI-IM, or SSB timing for CSI report #X transmitted in uplink time slot n′” refers to a set of CSI-RS timings, CSI-IM timings, and SSB timings that are not later than the CSI reference resources for CSI report #X to be transmitted in uplink time slot n′.

[0280] In an embodiment of the present disclosure, "the latest CSI-RS, CSI-IM or SSB opportunity among the CSI-RS, CSI-IM or SSB opportunities of CSI report #X transmitted in uplink slot n" may be interpreted in the following two ways.

[0281] -Explanation 2-1: A set of timings including the latest CSI-RS timing among the CSI-RS timings of CSI report #X transmitted in uplink time slot n', the latest CSI-IM timing among the CSI-RS timings of CSI report #X transmitted in uplink time slot n', and the latest SSB timing among the SSB timings of CSI report #0 transmitted in uplink time slot n'

[0282] Explanation 2-2: Latest timing among CSI-RS timing, CSI-IM timing, and SSB timing of CSI report #X transmitted in uplink slot n'

[0283] In the following embodiments of the present disclosure, two interpretations of “the latest CSI-RS, CSI-IM or SSB timing among the CSI-RS, CSI-IM or SSB timing of CSI report #X transmitted in uplink time slot n'” may be considered and applied separately. In addition, when considering the above two interpretations (Interpretation 1-1, Interpretation 1-2) of CSI-RS timing, CSI-IM timing and SSB timing, in an embodiment of the present disclosure, by considering all four different interpretations (application of Interpretation 1-1 and Interpretation 2-1, application of Interpretation 1-1 and Interpretation 2-2, application of Interpretation 1-2 and Interpretation 2-1, and application of Interpretation 1-1 and Interpretation 2-2), “the latest CSI-RS, CSI-IM or SSB timing among the CSI-RS, CSI-IM or SSB timing of CSI report #X transmitted in uplink time slot n'” may be applied separately.

[0284] The base station can guide CSI reporting by considering the amount of channel information that the UE can calculate simultaneously for CSI reporting, that is, the number of channel information calculation units (CSI processing units, CPUs) of the UE. When the number of channel information calculation units that the UE can calculate simultaneously is N CPU When N CPU The CSI reporting instructions from the base station that require more channel information calculation, or may not be considered more than N CPU Channel information updates that require more channel information calculations. CPU It may be reported by the UE to the base station via higher layer signaling, or may be configured by the base station via higher layer signaling.

[0285] Assume that the CSI report directed by the base station to the UE occupies the total number of channel information that the UE can calculate simultaneously N CPU For example, for each CSI report, when the number of channel information calculation units n (n=0, 1, ... N-1) required for the CSI report is Then the number of channel information calculation units required for a total of N CSI reports can be The channel information calculation unit required for each reportQuantity configured for the CSI report can be configured as shown in Table 21 below.

[0286] Table 21

[0287]

[0288] When the number of channel information calculations required by the UE for multiple CSI reports at a specific time point is greater than the number of channel information calculation units N that the UE can calculate simultaneously CPU, the UE may not consider updating the channel information of some CSI reports. Among the multiple indicated CSI reports, the CSI reports for which the channel information update is not considered are determined by at least considering the time that the calculation of the channel information required for the CSI report occupies the CPU and the priority of the channel information to be reported. For example, when the calculation of the channel information required for the CSI report occupies the CPU, the update of the channel information of the CSI report starting at the latest time may not be considered, and the update of the channel information of the CSI report with low priority may not be prioritized.

[0289] The priority of the channel information can be determined by referring to Table 22 below.

[0290] Table 22

[0291]

[0292] The CSI priority of the CSI report is determined by the priority value Pri in Table 22. iCSI (y, k, c, s). Referring to Table 31, the CSI priority value is determined according to the type of channel information included in the CSI report, the time domain reporting characteristics of the CSI report (aperiodic, semi-persistent, periodic), the channel for transmitting the CSI report (PUSCH, PUCCH), the serving cell index and the CSI report configuration index. The CSI priority comparison priority value Pri of the CSI report iCSI (y, k, c, s), and determine that the CSI report with a small priority value has a high CSI priority.

[0293] When the time occupied by the CPU for calculating the channel information required for the CSI report directed by the base station to the UE is called the CPU occupancy time, the CPU occupancy time is determined by considering the type of channel information included in the CSI report (report amount), the time domain characteristics of the CSI report (non-periodic, semi-persistent, periodic), the time slots or symbols occupied by the higher layer signaling or DCI guiding the CSI report, and part or all of the time slots or symbols occupied by the reference signal used to measure the channel state.

[0294] Based on the following Table 23, combinations between CSI report settings and CSI resource settings can be supported.

[0295] Table 23

[0296]

[0297] Figure 6 An example of an aperiodic CSI reporting method is shown.

[0298] exist Figure 6In the embodiment 600, the UE can obtain DCI format 0_1 ​​by monitoring PDCCH 601, and can obtain scheduling information and CSI request information for PUSCH 605 therefrom. The UE can obtain resource information of the CSI-RS 602 to be measured from the received CSI request indicator. The UE can determine the time point at which the CSI-RS 602 resource to be measured is to be transmitted based on the time point at which the DCI format 0_1 ​​is received and the CSI resource set configuration (for example, the parameter (the above-mentioned aperiodicTriggeringOffset) regarding the offset in the NZP CSI-RS resource set configuration (NZP-CSI-RS-ResourceSet)). More specifically, the UE can receive the configuration of the offset value X of the parameter aperiodicTriggeringOffset in the NZP-CSI-RS resource set configuration through higher layer signaling from the base station, and the configured offset value X can represent the offset between the time slot of the DCI for triggering the non-periodic CSI report and the time slot of the transmission CSI-RS resource. For example, the aperiodicTriggeringOffset parameter value and the offset value X may have a mapping relationship as described in Table 24 below.

[0299] Table 24

[0300] aperiodicTriggeringOffset Offset X 0 0 time slot 1 1 time slot 2 2 time slots 3 3 time slots 4 4 time slots 5 16 time slots 6 24 time slots

[0301] exist Figure 6 In example 600, an example in which the above offset value is configured as X=0 is shown. Here, the UE may receive a time slot ( Figure 6 606 in the DCI format 0_1) and can report CSI information measured using the received CSI-RS to the base station through the PUSCH 605. The UE can obtain scheduling information of the PUSCH 605 for CSI reporting from the DCI format 0_1 ​​(information corresponding to each field of the above-mentioned DCI format 0_1). For example, in the DCI format 0_1, the UE can obtain information about the time slot in which the PUSCH 605 is to be transmitted from the above-mentioned time domain resource allocation information for the PUSCH 605. Figure 6 In the example, the UE has obtained the K2 value corresponding to the time slot offset value of PDCCH to PUSCH as 3, and therefore, PUSCH 605 can be transmitted when PDCCH 601 has been received, that is, in time slot 3 609 which is three time slots away from time slot 0 606.

[0302] exist Figure 6In example 610, the UE can obtain DCI format 0_1 ​​by monitoring PDCCH 611, and can obtain scheduling information and CSI request information related to PUSCH 615 from it. The UE can obtain resource information of CSI-RS 612 to be measured from the received CSI request indicator. Figure 6 In example 610, an example of configuring the offset value of the CSI-RS as X=1 is shown. Here, the UE can receive the time slot of DCI format 0_1 ​​for triggering aperiodic CSI reporting (corresponding to Figure 6 The CSI-RS 612 is received in time slot 0 616) and the CSI information measured using the received CSI-RS can be reported to the base station through the PUSCH 615.

[0303] The non-periodic CSI report may include at least one or both of CSI Part 1 and CSI Part 2, and when the non-periodic CSI report is transmitted via PUSCH, the non-periodic CSI report may be multiplexed with the TB. For multiplexing, a CRC is inserted into the input bits of the non-periodic CSI, encoded and rate matched, and then mapped to a specific pattern in REs in the PUSCH and transmitted. Depending on the coding method or the length of the input bits, CRC insertion may be skipped. When multiplexing includes CSI Part 1 or CSI Part 2 in the non-periodic CSI report, the number of modulation symbols calculated for rate matching may be calculated as follows.

[0304]

[0305]

[0306] Specifically, in the case of PUSCH repetition transmission methods A and B, the UE can multiplex and transmit the aperiodic CSI report only in the first repetition transmission in the PUSCH repetition transmission. This is because the multiplexed aperiodic CSI report information is encoded using the polar code method, and in this case, in order to be multiplexed when transmitting multiple PUSCH repetitions, each PUSCH repetition should have the same frequency and time resource allocation. Specifically, in the case of PUSCH repetition transmission method B, each actual repetition can have a different OFDM symbol length, so the aperiodic CSI report can be multiplexed and transmitted only for the first PUSCH.

[0307] In addition, for PUSCH repetition transmission method B, when the UE schedules non-periodic CSI reporting without scheduling for TB or receives DCI that activates semi-periodic CSI reporting, the value of the nominal repetition can be assumed to be 1 even if the number of PUSCH repetition transmissions configured by higher layer signaling is greater than 1. In addition, when the UE schedules or activates non-periodic or semi-persistent CSI reporting without scheduling for TB, based on PUSCH repetition transmission method B, the UE can expect the first nominal repetition to be the same as the first actual repetition. After the semi-persistent CSI reporting has been activated by DCI, for PUSCH transmitted through semi-persistent CSI including PUSCH repetition transmission method B based on no scheduling for DCI, when the first nominal repetition is different from the first actual repetition, the transmission of the first nominal repetition can be ignored.

[0308] [PUSCH: About transmission scheme]

[0309] Next, the PUSCH transmission scheduling scheme will be described. PUSCH transmission can be dynamically scheduled through uplink grant (UL grant) in DCI, or operated through configured grant type 1 or type 2. Dynamic scheduling indication on PUSCH transmission can be made through DCI format 0_0 or 0_1.

[0310] A configured grant type 1 PUSCH transmission may be semi-statically configured by receiving a configuredGrantConfig including the rrc-ConfiguredUplinkGrant in Table 25 through higher signaling without receiving an UL grant within the DCI. A configured grant type 2 PUSCH transmission may be semi-persistently scheduled by an UL grant within the DCI after receiving a configuredGrantConfig not including the rrc-ConfiguredUplinkGrant in Table 25 through higher signaling. If the PUSCH transmission is operated by a configured grant, the parameters applied to the PUSCH transmission are applied by configuredGrantConfig (higher signaling) in Table 25, except for the scaling of dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank and UCI-OnPUSCH provided by pusch-Config (higher signaling) in Table 26. If transformPrecoder is provided within configuredGrantConfig (higher signaling) in Table 25, the UE applies tp-pi2BPSK within pusch-Config in Table 26 to PUSCH transmissions operated by the configured grant.

[0311] Table 25

[0312]

[0313]

[0314] Next, the PUSCH transmission method will be described. The DMRS antenna port used for PUSCH transmission is the same as the antenna port used for SRS transmission. Depending on whether the value of txConfig in pusch-Config in Table 26 (higher signaling) is "codebook" or "noncodebook", PUSCH transmission can follow a codebook-based transmission method and a non-codebook-based transmission method.

[0315] As described above, PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can be semi-statically configured through a configured grant. When an indication of scheduling of PUSCH transmission is received through DCI format 0_0, the UE performs beam configuration of PUSCH transmission by using the pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the uplink BWP activated within the serving cell, and the PUSCH transmission is based on a single antenna port. The UE does not expect scheduling of PUSCH transmission through DCI format 0_0 within a BWP where PUCCH resources including pucch-spatialRelationInfo are not configured. If the UE does not have a configured txConfig within the pusch-Config in Table 26, the UE does not expect scheduling through DCI format 0_1.

[0316] Table 26

[0317]

[0318]

[0319] In the following, codebook-based PUSCH transmission will be described. Codebook-based PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can be operated semi-statically through the configured grant. If the codebook-based PUSCH is dynamically scheduled through DCI format 0_1, or the codebook-based PUSCH is semi-statically configured through the configured grant, the UE determines the precoder for PUSCH transmission based on the SRS resource indicator (SRI), the transmission precoding matrix indicator (TPMI) and the transmission rank (the number of PUSCH transmission layers).

[0320] The SRI may be given by the SRS resource indicator (field within the DCI) or configured by the srs-ResourceIndicator (higher signaling). During codebook-based PUSCH transmission, the UE has at least one SRS resource configured for it and may have up to two SRS resources configured for it. If the SRI is provided to the UE by the DCI, the SRS resource indicated by the corresponding SRI refers to the SRS resource corresponding to the SRI in the SRS resource transmitted before the PDCCH including the corresponding SRI. The TPMI and transmission rank may be given by "precoding information and number of layers" (field within the DCI) or configured by precodingAndNumberOfLayers (higher signaling). The TPMI is used to indicate the precoder to be applied to the PUSCH transmission. If one SRS resource is configured for the UE, the TPMI may be used to indicate the precoder to be applied in one of the configured SRS resources. If multiple SRS resources are configured for the UE, the TPMI is used to indicate the precoder to be applied in the SRS resource indicated by the SRI.

[0321] The precoder to be used for PUSCH transmission may be selected from an uplink codebook having the same number of antenna ports as the value of nrofSRS-Port in SRS-Config (higher signaling). In conjunction with codebook-based PUSCH transmission, the UE determines the codebook subset based on pusch-Config (higher signaling) and codebookSubset in TPMI. Based on the UE capabilities reported by the UE to the base station, the codebook subset in pusch-Config (higher signaling) may be configured as one of "fullyAndPartialAndNonCoherent", "partialAndNonCoherent", and "noncoherent". If the UE reports "partialAndNonCoherent" as the UE capability, the UE does not expect the value of codebookSubset (higher signaling) to be configured as "fullyAndPartialAndNonCoherent". Additionally, if the UE reports "nonCoherent" as the UE capability, the UE does not expect the value of codebookSubset (higher signaling) to be configured as "fullyAndPartialAndNonCoherent" or "PartialAndNonCoherent". If nrofSRS-Ports within SRS-ResourceSet (higher signaling) indicates two SRS antenna ports, the UE does not expect the value of codebookSubset (higher signaling) to be configured as "partialAndNonCoherent".

[0322] The UE may be configured with one SRS resource set, where the usage value in SRS-ResourceSet (higher signaling) is "codebook", and one SRS resource may be indicated by the SRI in the corresponding SRS resource set. If multiple SRS resources are configured in an SRS resource set, where the usage value in SRS-ResourceSet (higher signaling) is "codebook", the UE expects the value of nrofSRS-Ports in SRS-Resource (higher signaling) to be the same for all SRS resources.

[0323] The UE transmits one or more SRS resources included in the SRS resource set to the base station, where the usage value is configured as a "codebook" according to higher signaling, and the base station selects one from the SRS resources transmitted by the UE and indicates that the UE is able to transmit PUSCH by using the transmission beam information of the corresponding SRS resource. In conjunction with codebook-based PUSCH transmission, SRI can be used as information for selecting an index of an SRS resource and can be included in the DCI. In addition, the base station adds information indicating the rank and TPMI used by the UE for PUSCH transmission to the DCI. Using the SRS resources indicated by SRI, the UE applies the precoder indicated by the rank and TPMI (which is based on the transmission beam indication of the corresponding SRS resource) when performing PUSCH transmission, thereby performing PUSCH transmission.

[0324] Next, non-codebook based PUSCH transmission will be described. Non-codebook based PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can be operated semi-statically through the configured grant. If at least one SRS resource is configured in the SRS resource set, where the usage value in SRS-ResourceSet (higher signaling) is "non-codebook", non-codebook based PUSCH transmission can be scheduled for the UE through DCI format 0_1.

[0325] Regarding SRS resource sets, where the usage value within the SRS-ResourceSet (higher signaling) is "nonCodebook", a connected NZP CSI-RS resource (non-zero power CSI-RS) may be configured for the UE. The UE may calculate the precoder for the SRS transmission by measuring the NZP CSI-RS resources connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the aperiodic SRS transmission in the UE is less than 42 symbols, the UE does not expect the information about the precoder for the SRS transmission to be updated.

[0326] If the configured value of resourceType within SRS-ResourceSet (higher signaling) is "aperiodic", the connected NZP CSI-RS is indicated by an SRS request, which is a field within DCI format 0_1 ​​or 1_1. If the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the presence of the connected NZP CSI-RS can be indicated for the case where the value of the SRS request (field within DCI format 0_1 ​​or 1_1) is not "00". The corresponding DCI should not indicate cross-carrier or cross-BWP scheduling. In addition, if the value of the SRS request indicates the presence of NZP CSI-RS, the NZP CSI-RS is located in the time slot used to transmit the PDCCH including the SRS request field. In this case, the TCI state configured for the scheduled subcarrier is not configured as QCL-TypeD.

[0327] If a periodic or semi-persistent SRS resource set is configured, the connected NZP CSI-RS may be indicated by the associatedCSI-RS within the SRS-ResourceSet (higher signaling). Regarding non-codebook based transmission, the UE does not expect that the spatialRelationInfo as higher signaling about the SRS resources and the associatedCSI-RS within the SRS-ResourceSet (higher signaling) will be configured together.

[0328] If multiple SRS resources are configured for the UE, the UE can determine the precoder and transmission rank to be applied to the PUSCH transmission based on the SRI indicated by the base station. The SRI can be indicated by the SRS resource indicator (field within the DCI) or configured by the srs-ResourceIndicator (higher signaling). Similar to the above-mentioned codebook-based PUSCH transmission, if the SRI is provided to the UE through the DCI, the SRS resources indicated by the corresponding SRI in the SRS resources transmitted before the PDCCH including the corresponding SRI refer to the SRS resources corresponding to the SRI. The UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be transmitted simultaneously in the same symbol in an SRS resource set and the maximum number of SRS resources are determined by the UE capabilities reported by the UE to the base station. The SRS resources transmitted simultaneously by the UE occupy the same RB. The UE configures an SRS port for each SRS resource. There may be only one configured SRS resource set, where the usage value within the SRS-ResourceSet (higher signaling) is "nonCodebook", and a maximum of four SRS resources may be configured for non-codebook based PUSCH transmissions.

[0329] The base station may transmit one NZP-CSI-RS connected to an SRS resource set to the UE, and the UE may calculate the precoder to be used when transmitting one or more SRS resources within the corresponding SRS resource set based on the measurement result when the corresponding NZP-CSI-RS is received. When transmitting one or more SRS resources in the SRS resource set to the base station, the UE applies the calculated precoder, where the configured use is "nonCodebook", and the base station selects one or more SRS resources from the received one or more SRS resources. In conjunction with non-codebook based PUSCH transmission, the SRI indication may represent an index of one SRS resource or a combination of multiple SRS resources, and the SRI is included in the DCI. The number of SRS resources indicated by the SRI transmitted by the base station may be the number of transmission layers of the PUSCH, and the UE transmits the PUSCH by applying the precoder applied to the SRS resource transmission to each layer.

[0330] In the following description of the present disclosure, higher layer signaling may refer to signaling corresponding to at least one of the following signalings or a combination of one or more thereof.

[0331] -MIB

[0332] -SIB or SIB X (X = 1, 2, ...)

[0333] -RRC signaling

[0334] -MAC CE

[0335] -UE Capability Report

[0336] -UE assistance information or message

[0337] In addition, L1 signaling may refer to signaling corresponding to at least one signaling method among signaling methods using the following physical layer channels or signaling or a combination of one or more thereof.

[0338] -PDCCH

[0339] -DCI

[0340] -UE-specific DCI

[0341] -Group Common DCI

[0342] - Public DCI

[0343] Scheduling DCI (e.g., DCI for scheduling downlink or uplink data)

[0344] - Non-scheduled DCI (e.g., DCI not used for scheduling downlink or uplink data)

[0345] -PUCCH

[0346] -DCI

[0347] <First embodiment: Subband channel state information reporting method>

[0348] In one example of the present disclosure, a method for reporting subband channel state information in a wireless communication system is described. In the case where a UE performs subband channel state information reporting, the UE may semi-statistically receive a configuration of the channel state information about the subband from a base station, which is reported by the UE via the csi-ReportingBand configured in CSI-ReportConfig, which is a higher layer signaling defined in Table 17 above.

[0349] -csi-ReportingBand is higher layer signaling, which is not configured when the size of BWP is less than 24 PRBs, and can be configured when the size of BWP is equal to or greater than 24 PRBs.

[0350] -csi-ReportingBand is higher layer signaling and can be selected as one of the bitmaps with a length of 3 to 19, and the length of the bitmap can be determined by the relationship between the size of the subband indicated by each bit in the bitmap and the size of the BWP, which will be described later.

[0351] -The size of the subband indicated by each bit in the bitmap can be selected as one of value1 and value2 according to subbandSize, which is higher layer signaling, and value1 and value2 can vary according to the size of the BWP, that is, the total number of RBs of the BWP. For example, when the total number of RBs of the BWP is 24 to 72, value1 and value2 can be 4 and 8 PRBs, respectively; when the total number of RBs of the BWP is 73 to 144, value1 and value2 can be 8 and 16 PRBs, respectively; and when the total number of RBs of the BWP is 145 to 275, value1 and value2 can be 16 and 32 PRBs, respectively.

[0352] - When the size of BWP is 24 PRBs, the number of subbands that can be represented is 3 when value2 is 8 PRBs; when the size of BWP is 72 PRBs, the number of subbands that can be represented is 18 when value1 is 4 PRBs; and when the size of BWP is 275 PRBs, the number of subbands represented can be 18 when value1 is 16 PRBs if the starting CRB value of BWP is divided by the size of the subband, and can be 19 if the starting CRB value of BWP is not divided by the size of the subband. Therefore, the bitmap can have a length from a minimum of 3 to a maximum of 19, and one of them can be selected.

[0353] -The bits at the predefined positions in the bitmap may have a bit value of 0 or 1, and when the bit value at the predefined position in the bitmap is 1, this may mean that the UE should report the subband channel state information of the corresponding subband. Because each bit in the bitmap has a value of 0 or 1, the UE can report the subband channel state information of a group of consecutive or non-consecutive subbands in the BWP.

[0354] -When the UE is configured to report wideband PMI and CQI via higher layer signaling, the UE may calculate the wideband PMI and CQI by considering all subbands corresponding to the 1 value in the bitmap, and report it to the base station. In the case where the UE is configured to report subband PMI and CQI via higher layer signaling, the UE may calculate the subband PMI and CQI for each subband corresponding to the 1 value in the bitmap, and report it to the base station.

[0355] When the UE is configured to report subband PMI and CQI via higher layer signaling, and the channel state information report is divided into two parts (two-part CSI), the UE can include the subband channel state information in the second part of the channel state information (CSI part 2), and the sequence of the included information can be as follows.

[0356] - Differential CQI for each subband of the second TB for even subbands, sorted in ascending order

[0357] - The PMI of each subband of the second TB with respect to even subbands, which are sorted in ascending order

[0358] - Differential CQI for each subband of the second TB for odd subbands, sorted in ascending order

[0359] - PMI of each subband of the second TB with respect to odd subbands, with the odd subbands sorted in ascending order

[0360] In order to generate such information, there are two methods to determine the subband index to distinguish between even and odd subbands.

[0361] [Index method 1] Index determination method based on the value "1" in the bitmap

[0362] -When determining the index of the subband, the UE can determine the index of the subband based on the value "1" in the above-mentioned csi-ReportingBand bitmap. Therefore, when different UEs are configured with the same length of csi-ReportingBand bitmap, and the values ​​of the two bitmaps are different, even if the subbands used by the two UEs to report the channel status are the same bit positions in the two bitmaps, their indexes can be allocated differently according to the value "1". Therefore, even and odd subbands can also be different according to the bitmap.

[0363] -In the example, when the csi-ReportingBand bitmap of length 10 is "1110111011", since the subband corresponds to the lowest frequency subband, the UE may determine the subband corresponding to the rightmost "1" in the bitmap as subband 0, and may assign the subband index to the subband corresponding to the remaining "1" in the sequence. In this case, the UE may assign the subband index to the position "1" in the bitmap in ascending order from right to left. Therefore, according to the bitmap, eight subband indexes from subband 0 to 7 may be assigned to the subband corresponding to "1" in the bitmap, and the subband corresponding to the middle two "0" bits may not have a corresponding subband index.

[0364] [Index method 2] Index determination method based on the absolute position of the bit in the bitmap

[0365] -When determining the index of the subband, the UE can determine the index of the subband based on the absolute position of the bit in the above-mentioned csi-ReportingBand bitmap. Therefore, when different UEs are configured with csi-ReportingBand bitmaps of the same length, and even if the values ​​of the two bitmaps are different, when the same bit position in the two bitmaps has a value of "1", the two UEs can be assigned the same subband index in the subband corresponding to the bit at the corresponding position. Therefore, even and odd subbands have been determined regardless of the bitmap, and whether to report the channel state information of the predefined subband can be determined according to the value "1" of the bitmap.

[0366] For example, when the csi-ReportingBand bitmap of length 10 is "1110111011", the index of the subband is determined based on the absolute position of the bit in the bitmap, and thus the subband with the lowest frequency band corresponds to the rightmost bit in the bitmap, and the subband is determined to be subband 0. Thereafter, the subband indexes are assigned to the corresponding subbands in ascending order. In the example, the UE can perform subband channel status reporting for subbands 0, 1, 3, 4, 5, 7, 8, and 9. The UE can also assign subband indexes 2 and 6 to the middle two "0" bit positions, but the subbands corresponding to "0" are not used to report subband channel status information.

[0367] The specific examples of indexing methods 1 and 2 above are merely examples, and at least one obvious variation is possible, such as assigning subband indices in descending order, assigning indices starting from the subband with the highest frequency band, or assigning indices starting from the subband corresponding to the leftmost "1" in the bitmap.

[0368] Figure 7 An example of a method of allocating a subband index when reporting subband channel state information according to the present disclosure is shown. Figure 7 , it can be assumed that the CSI-Reporting bitmap is configured as "1011101110" (indicated by reference numeral 700). For the corresponding bitmap, according to [Index Method 1] (indicated by reference numeral 701), the index of the subband is determined only based on the position in the bitmap to which the value "1" is assigned, and thus the even subband can be determined as B, D, G, and J, and the odd subband can be determined as C, F, and H (indicated by reference numeral 703). On the other hand, according to [Index Method 2] (indicated by reference numeral 702), the index of the subband is determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as C and G, and the odd subband can be determined as B, D, F, H, and J (indicated by reference numeral 704). Here, A to J represent the frequency positions of the subbands within the BWP. For example, when the size of the BWP is 80 PRBs and the size of the subband is determined to be 8 PRBs via higher layer signaling, A may represent a frequency range of PRB 0 to PRB 7, and J may represent a frequency range of PRB 72 to PRB 79.

[0369] According to the above description, even if the UE has been configured with the csi-ReportingBand bitmap as a higher layer signaling, the subband index allocation may be different depending on the indexing method used, and therefore, the even and odd subbands may be correspondingly different. Therefore, when reporting the above-mentioned subband channel status information, information about even and odd subbands may be allocated and reported to the base station differently. Specifically, when the UE generates subband channel status report information using [Index Method 1], and the base station decodes and interprets the subband channel status report information reported from the UE based on [Index Method 2], there may be a mismatch in understanding between the base station and the UE regarding the subband channel status report information.

[0370] <Second Embodiment: Another Method for Subband Channel State Information Reporting>

[0371] According to an embodiment of the present disclosure, when at least one entity in a base station and a UE uses different indexing methods to determine a subband index, various methods are described to ensure a consistent understanding of subband channel state information by limiting the CSI-ReportingBand bitmap configuration, even when different entities use different indexing methods within a given BWP. Basically, the following various methods can be used to make the index assigned to the subband itself the same, or to make the even and odd subbands used as the basis for reporting subband channel state information the same even if the subband indexes are different.

[0372] Therefore, the base station can use the following method to configure the bitmap so as to allow the base station and the UE to use the bitmap for the subband channel status report based on the same subband index. In addition, the UE can use the following method to expect to receive the bitmap configuration so that the base station and the UE use the bitmap to report the subband channel status information based on the same subband index.

[0373] In addition, the base station may use the following method to configure a bitmap for the UE so that the base station and the UE may use the same even and odd subbands to perform subband channel status reporting.

[0374] In addition, the UE may use the following method to expect to receive a bitmap configuration so that the base station and the UE may perform subband channel status reporting using the same even and odd subbands.

[0375] In addition, the base station may use the following method to configure a bitmap for the UE so that the base station and the UE use the same even and odd subbands to perform subband channel status reporting even if the base station and the UE have different understandings of the subband index.

[0376] In addition, the UE may use the following method to expect to receive a bitmap configuration so that the base station and the UE perform subband channel status reporting using the same even and odd subbands, even if the base station and the UE have different understandings of the subband indexes.

[0377] [Bitmap configuration method 1]

[0378] The base station may not know whether the base station and the UE have the same or different understandings of the subband index determination method. Therefore, the base station may configure the UE with a csi-ReportingBand bitmap in which all bits have a value of "1". Since the UE may not know whether the base station and the UE have the same or different understandings of the subband index determination method, the UE may expect to receive a csi-ReportingBand bitmap configured with all bits as "1" from the base station. Therefore, the UE can expect that the base station and the UE have the same understanding of the subband index.

[0379] Figure 8 An example of a method for deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown. Figure 8 In the CSI-Reporting bitmap, it can be assumed that the CSI-Reporting bitmap is configured as 1111111111 (indicated by reference numeral 800). For the corresponding bitmap, according to [Index Method 1] (indicated by reference numeral 801), the index of the subband is determined only based on the position assigned with the value "1", and thus the even subband can be determined as A, C, E, G, and I, and the odd subband can be determined as B, D, F, H, and J (indicated by reference numeral 803). In addition, according to [Index Method 2] (indicated by reference numeral 802), the index of the subband is determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as A, C, E, G, and I, and the odd subband can be determined as B, D, F, H, and J (indicated by reference numeral 804).

[0380] Since all bits in the bitmap have a value of "1", the subband index of a specific subband can be configured to be the same, regardless of whether the subband index is determined based on a relative position [Index Method 1] or an absolute position [Index Method 2], and the UE and the base station may have the same understanding of even and odd subband indices.

[0381] [Bitmap configuration method 2]

[0382] The base station may not know whether the base station and the UE have the same or different understandings of the subband index determination method. Therefore, the base station may configure the UE with a bitmap having a value of continuous "1" from the rightmost bit of the CSI-ReportingBand bitmap. Since the UE may not know whether the base station and the UE have the same or different understandings of the subband index determination method, the UE may expect to receive a CSI-ReportingBand bitmap with a continuous value of "1" from the rightmost bit from the base station.

[0383] Fig. 9 Another example of a method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown. Fig. 9 , it can be assumed that the csi-reporting bitmap is configured as 0000011111 (indicated by reference numeral 900). For the corresponding bitmap, according to [index method 1] (indicated by reference numeral 901), the index of the subband is determined only based on the position where the value "1" is assigned, and thus the even subband can be determined as A, C, and E, and the odd subband can be determined as B and D (indicated by reference numeral 903). In addition, according to [index method 2] (indicated by reference numeral 902), the index of the subband is determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as A, C, E, and the odd subband can be determined as B and D (indicated by reference numeral 904).

[0384] In the bitmap, all consecutive bits from the rightmost bit have a value of "1", the subband index of a specific subband can be configured to be the same, regardless of whether the subband index is determined based on a relative position [Index Method 1] or an absolute position [Index Method 2], and the UE and the base station may also have the same understanding of even and odd subband indices.

[0385] [Bitmap configuration method 3]

[0386] The base station may not know whether the base station and the UE have the same or different understandings of the subband index determination method. Therefore, for the CSI-ReportingBand bitmap to be transmitted to the UE, the base station can configure an even number of consecutive "0s" in the rightmost bit position of the bitmap, so that the lowest subband whose corresponding bit is configured as "1" belongs to an even subband, and can configure consecutive "1s" in the bit position to the left of this bit position. The UE may expect to receive a CSI-ReportingBand bitmap from the base station, which is configured so that the lowest subband is an even subband. In other words, the UE may expect to receive a CSI-ReportingBand bitmap from the base station, which is configured to have an even number of consecutive "0s" in the rightmost bit position and consecutive "1s" in the bit position to the left of this bit position.

[0387] Therefore, when the CSI-ReportingBand bitmap is interpreted based on [Index Method 1] and [Index Method 2], this method allows the UE to expect to have the same understanding of even and odd subbands as the base station. In addition, when the UE receives the configuration of the CSI-ReportingBand bitmap from the base station, if the bitmap is interpreted based on [Index Method 1] and [Index Method 2], the UE can expect the even subbands to have the same frequency position and the odd subbands to have the same frequency position, regardless of the method to be used. The UE can expect to receive a CSI-ReportingBand bitmap from the base station, which is configured so that the bit position "1" that appears first from the right side of the bitmap is configured in the odd bit position, such as the first, third, fifth, etc. from the right side of the bitmap.

[0388] Fig.10 Another example of a method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown. Fig.10 , it can be assumed that the CSI-Reporting bitmap is configured as 0011111100 (indicated by reference numeral 1000). For the bitmap, according to [Index Method 1] (indicated by reference numeral 1001), the index of the subband is determined only based on the position where the value "1" is assigned, and thus the even subband can be determined as C, E, and G, and the odd subband can be determined as D, F, and H (indicated by reference numeral 1003). In addition, according to [Index Method 2] (indicated by reference numeral 1002), the index of the subband can be determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as C, E, and G, and the odd subband can be determined as D, F, and H (indicated by reference numeral 1004).

[0389] In the corresponding bitmap, an even number of consecutive "0"s are configured at the rightmost bit position, and therefore when the two indexing methods are used, although the lowest frequency even subbands may not have the same index, the lowest even subbands may have the same frequency position. Therefore, according to [Index Method 1] and [Index Method 2], the subband indexes of frequency position C are 0 and 2, respectively, but when the UE reports subband channel status information via the corresponding bitmap, these two subband indexes can be the lowest even subband indexes. Similarly, according to [Index Method 1] and [Index Method 2], the subband indexes of frequency position D are 1 and 3, respectively, but when the UE reports subband channel status information via the corresponding bitmap, these two subband indexes can be the lowest odd subband indexes.

[0390] When the UE reports subband channel state information, since the PMI and CQI information of the even subband is generated and reported in ascending order from the lowest index of the even subband, even if the subband index is different, the subbands corresponding to the even and odd subband indices have the same frequency position, and therefore even if the base station and the UE use different indexing methods, they can ensure a consistent understanding of the generated information and its interpretation when reporting the subband channel state information.

[0391] [Bitmap configuration method 4]

[0392] The base station may not know whether the base station and the UE have the same or different understandings of the subband index determination method. Therefore, for the csi-ReportingBand bitmap transmitted from the base station, the UE may expect the first bit position "1" in the bitmap to be configured to exist in odd bit positions starting from the right side of the bitmap, such as the first, third, fifth, etc. from the right side of the bitmap. In addition, if the base station wants to configure a discontinuous subband channel state information report for the UE, the base station may configure an even number of consecutive "0"s to the left of the position of the first "1" that occurs on the far right of the bitmap to be transmitted to the UE. Similarly, for the purpose of receiving the configuration of the discontinuous subband channel state information report from the base station, the UE may expect to receive an even number of consecutive "0"s to the left of the position of the first "1" that occurs on the far right of the bitmap from the base station. In addition, the UE does not expect to receive an odd number of consecutive "0"s from the base station, which are located to the left of the first "1" position that occurs on the far right of the bitmap.

[0393] Therefore, when interpreting the CSI-ReportingBand bitmap based on [Index Method 1] and [Index Method 2], the UE can expect to have the same understanding of even and odd subbands as the base station. When the UE receives the configuration of the CSI-ReportingBand bitmap from the base station, the UE can expect the even subbands to have the same frequency position and the odd subbands to have the same frequency position, and interpret the bitmap based on [Index Method 1] and [Index Method 2].

[0394] Fig.11 Another example of a method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown. Fig.11, it can be assumed that the csi-Reporting bitmap is configured as 1001001001 (indicated by reference numeral 1100). For the corresponding bitmap, according to [Index Method 1] (indicated by reference numeral 1201), the index of the subband is determined using only the position assigned with the value "1", and thus the even subband can be determined as A and G, and the odd subband can be determined as D and J (indicated by reference numeral 1103). In addition, according to [Index Method 2] (indicated by reference numeral 1102), the index of the subband is determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as A and G, and the odd subband can be determined as D and J (indicated by reference numeral 1104).

[0395] In the corresponding bitmap, the position of the bit of "1" that first appears from the right side of the bitmap exists in an odd bit position, such as the first, third, fifth, etc. from the right side of the bitmap, and therefore when two indexing methods are used, although the lowest frequency even subbands may not be configured to have the same index, the subbands with the lowest even index may be configured to have the same frequency position. Therefore, according to [Index Method 1] and [Index Method 2], even if the subband index at frequency position A is 0 and the subband index at frequency position G is different and is 2 and 6 respectively, the same frequency position may correspond to the same even subband. Similarly, according to [Index Method 1] and [Index Method 2], the subband indexes at frequency position D are 1 and 3 respectively, but when the UE reports subband channel state information via a bitmap, these two subband indexes may be the lowest odd subband indexes.

[0396] In this way, when the UE reports subband channel state information, since the PMI and CQI information of the even subbands are generated and reported in ascending order from the lowest index of the even subbands, and the PMI and CQI information of the odd subbands are generated and reported in ascending order from the lowest index of the odd subbands, even if the subband indices are different, the frequency positions of the subbands corresponding to the even and odd subband indices are the same, and therefore even if the base station and the UE use different indexing methods, when reporting the subband channel state information, they can ensure a consistent understanding of the generated information and its interpretation.

[0397] Fig.12 Another example of a method capable of deriving the same operation in different sub-band channel state information reporting methods according to the present disclosure is shown. Fig.12In the CSI-Reporting bitmap, it is assumed that it is configured as 1100001100 (indicated by reference numeral 1200). For the corresponding bitmap, according to [Index Method 1] (indicated by reference numeral 1201), the index of the subband is determined only based on the position where the value "1" is assigned, and thus the even subband can be determined as C and I, and the odd subband can be determined as D and J (indicated by reference numeral 1203). In addition, according to [Index Method 2] (indicated by reference numeral 1202), the index of the subband is determined based on the absolute position of the bit in the bitmap, regardless of whether the value is "1" or "0", and thus the even subband can be determined as C and I, and the odd subband can be determined as D and J (indicated by reference numeral 1204).

[0398] In the bitmap, the bit position "1" that first appears from the right side of the bitmap is located at the third bit position, that is, the odd bit position from the right side of the bitmap, and therefore even when two indexing methods are used, although the indexes of the lowest frequency even bit positions may not be the same, the lowest even subbands can be configured to have the same frequency position. Therefore, according to [Index Method 1] and [Index Method 2], the subband indexes at frequency position C are different and are 0 and 2, respectively, but the same frequency position can correspond to the same even subband. Similarly, according to [Index Method 1] and [Index Method 2], the subband indexes at frequency position D are 1 and 3, respectively, but when the UE reports subband channel state information via the corresponding bitmap, these two subband indexes can be the lowest frequency odd subband indexes.

[0399] In this way, when the UE reports subband channel state information, since the PMI and CQI information of the even subband is generated and reported in ascending order from the lowest index of the even subband, and the PMI and CQI information of the odd subband is generated and reported in ascending order from the lowest index of the odd subband, even if the subband indices are different, the frequency positions of the subbands corresponding to the even and odd subband indices are the same, and therefore even if the base station and the UE use different indexing methods, when reporting the subband channel state information, they can ensure a consistent understanding of the generated information and its interpretation.

[0400]

Bitmap determination method 5

[0401] The UE and the base station may determine the index of the subband for reporting the channel state information based on the above-mentioned [Index Method 1] or [Index Method 2].

[0402] In the example, a UE and a base station supporting 5G NR may determine the index of a subband based on [Index Method 1] or [Index Method 2] regardless of which version (release) of the corresponding NR function is used.

[0403] In another example, a UE and a base station supporting 5G NR may determine the index of a subband based on [Index Method 1] or [Index Method 2] depending on which version (release) of the corresponding NR function is used.

[0404] -For example, for a UE and a base station supporting Release 15 or 16, the index of the subband may be determined based on [Index Method 1], and for a UE and a base station supporting Release 17 and higher, the index of the subband may be determined based on [Index Method 2].

[0405] -As another example, a UE and a base station supporting Release 15 or 16 may use different indexing methods, and there may be no explicit signaling of which indexing method the UE and the base station are using. In this case, the base station restrictively provides the UE with csi-ReportingBand configuration information as higher layer signaling based on the above [Bitmap Determination Method 1] to [Bitmap Determination Method 4] to ensure understanding between different indexing methods.

[0406] In another example, with respect to UEs and base stations supporting Release 15 or 16, the base station can distinguish the manufacturer of a specific UE by using an implementation method, and can assume that one of the two indexing methods is used for each UE manufacturer. For example, when the base station can identify the manufacturer of a specific UE and the manufacturer assumes [Index Method 1], even if the UE does not report to the base station explicit signaling about which indexing method the UE uses when determining the subband index, the base station can assume that the UE determines the subband index based on [Index Method 1]. When all UEs connected to a base station within a specific BWP, cell, or cell group are UEs from one manufacturer, and the base station uses the same indexing method assumed by the manufacturer, the base station can operate based on the indexing method assumed by the manufacturer. Otherwise, the base station can restrictively provide the UE with csi-ReportingBand configuration information as higher layer signaling based on the above-mentioned [Bitmap Determination Method 1] to [Bitmap Determination Method 4] to ensure understanding between different indexing methods.

[0407] When the base station and the UE operate based on one of the two indexing methods as described above, the following operations are possible.

[0408] -The UE may assume that the base station and the UE determine the index of the subband based on the above-mentioned [Index Method 1]. In other words, the UE may determine the subband at the rightmost "1" position in the csi-ReportingBand bitmap configured as higher layer signaling as the lowest index subband (ie, subband 0), and may determine the index of the subband in ascending order by using the bit with a value of "1" to the left of the rightmost bit of the bitmap.

[0409] -In addition, the base station may assume that the UE and the base station determine the index of the subband based on the above-mentioned [Index Method 1]. In other words, the base station may determine the subband at the rightmost "1" position in the csi-ReportingBand bitmap configured for the UE via higher layer signaling as the lowest index subband (ie, subband 0), and may determine the index of the subband in ascending order by using the bit with a value of "1" to the left of the rightmost bit of the bitmap.

[0410] -In addition, the UE may assume that the base station and the UE determine the index of the subband based on the above-mentioned [Index Method 2]. In other words, regardless of whether the value of each bit in the csi-ReportingBand bitmap configured for the UE through higher layer signaling is "0" or "1", the UE may determine the subband at the rightmost bit position in the bitmap as the subband with the lowest index (ie, subband 0), and determine the index of the subband in ascending order by using the bit with a value of "1" to the left of the rightmost bit of the bitmap.

[0411] In addition, the UE may assume that the base station and the UE determine the index of the subband based on the above-mentioned [Index Method 2]. In other words, regardless of whether the value of each bit in the csi-ReportingBand bitmap configured for the UE via higher layer signaling is "0" or "1", the base station may determine the subband at the rightmost bit position in the bitmap as the subband with the lowest index (ie, subband 0), and determine the subband index in ascending order by using the bit with a value of "1" to the left of the rightmost bit of the bitmap.

[0412] Regarding the above-mentioned [Bitmap Determination Method 1] to [Bitmap Determination Method 5], the UE may perform a UE capability report to inform the base station that it is possible to support a specific method. Alternatively, the UE may perform a UE capability report indicating that the UE is implemented using one of the two methods of [Index Method 1] or [Index Method 2] mentioned above, or indicating that implementation of both methods is possible. Alternatively, when the UE reports the predefined UE capability of Release 15 or 16 functions to the base station instead of explicit signaling for the above-mentioned two index methods, the base station may assume that the UE supports one of [Index Method 1] and [Index Method 2] (for example, it may assume that [Index Method 1] is supported), and use one of the above-mentioned [Bitmap Determination Method 1] to [Bitmap Determination Method 4] to perform restrictive operations.

[0413] Alternatively, when a UE of Release 15 or 16 implements a UE capability report that explicitly means that one or both of the above two indexing methods are supported by using an earlier implementable function, and the base station receiving the UE capability report also has a function capable of interpreting the earlier implementable function, the base station can identify which of the above two indexing methods the UE uses to allocate subband indexes, and based on the information, the base station can support one of [Bitmap Determination Method 1] to [Bitmap Determination Method 5] for the UE. Alternatively, if the UE does not explicitly signal the two indexing methods but reports the predefined UE capability in the Release 17 function to the base station, or if the base station can identify the version of the UE, that is, the base station can identify the version information of the UE and the version is Release 17, the base station can assume that the UE supports one of [Indexing Method 1] and [Indexing Method 2] (for example, it can assume that [Indexing Method 1] is supported) and use one of the above [Bitmap Determination Method 1] to [Bitmap Determination Method 4] to perform a restrictive operation.

[0414] Alternatively, when the UE reports explicit signaling of the above two indexing methods to the base station, the base station may assume that the UE supports one of [indexing method 1] and [indexing method 2] (for example, it may assume support for [indexing method 1]), and may configure additional higher layer signaling for each UE. The corresponding higher layer signaling may mean performing one of a total of three situations, so that when the UE reports the subband channel state information, the UE operates in [indexing method 1] or [indexing method 2], or operates in a restrictive manner based on one of the above [bitmap determination method 1] to [bitmap determination method 4].

[0415] Fig.13a An example of operations performed by a UE according to an embodiment of the present disclosure is shown.

[0416] The UE may transmit UE capabilities to the base station (operation 1301). At this time, the UE capabilities may follow the above information. For example, the UE capabilities may express specific functions of Release 15, 16 or higher to support 5G NR, may be UE capabilities that have the meaning of supporting one or both of the above [Index Method 1] or [Index Method 2], and may include all of these. Thereafter, the UE may receive higher layer signaling from the base station (operation 1302). At this time, the UE may receive a csi-ReportingBand as a higher layer signaling for reporting subband channel state information, and the csi-ReportingBand may be generated by the base station based on the above [Bitmap Determination Method 1] to [Bitmap Determination Method 5]. Thereafter, the UE may receive a reference signal from the base station (operation 1303), and may generate subband channel state information based on the channel state information measured using the reference signal (operation 1304). In this case, the UE may generate the channel state information of the subband indicated by the corresponding csi-ReportingBand bitmap by assuming one of the above [Index Method 1] and [Index Method 2]. Thereafter, the UE may report the subband channel state information to the base station (operation 1305). At least one of the above operations may be skipped, other operations may be added, or their order may be changed to perform the present disclosure.

[0417] Fig.13b An example of operations performed by a base station according to an embodiment of the present disclosure is shown.

[0418] The base station may receive UE capabilities transmitted by the UE (operation 1351). At this time, the UE capabilities may follow the above information. For example, the UE capabilities may express specific functions of Release 15, 16 or higher to support 5G NR, may be UE capabilities having the meaning of supporting one or both of the above [Index Method 1] or [Index Method 2], and may include all of these. Thereafter, the base station may transmit higher layer signaling to the UE (operation 1352). At this time, the base station may transmit a csi-ReportingBand as a higher layer signaling for reporting subband channel state information to the UE, and the csi-ReportingBand may be generated by the base station based on the above [Bitmap Determination Method 1] to [Bitmap Determination Method 5]. Thereafter, the base station may transmit a reference signal to the UE (operation 1353), and the base station may receive the subband channel state information generated by the UE by receiving the corresponding reference signal (operation 1354). In this case, the base station can decrypt and decode the subband channel state information that has been received from the UE, and can assume that one of the above-mentioned [index method 1] and [index method 2] is applied to interpret the subband channel state information (operation 1355). In other words, based on the above-mentioned index method 1 or index method 2, the base station can identify the subband associated with the received subband channel state information. At least one of the above-mentioned operations can be skipped, other operations can be added, or their order can be changed to perform the present disclosure.

[0419] Fig.14 is a block diagram showing the structure of a UE according to an embodiment of the present disclosure.

[0420] refer to Fig.14 , the UE may include a transceiver 1401, a memory 1402, and a processor 1403. The components of the UE are not limited to the above examples. For example, the UE may include a greater or lesser number of components than the above components. In addition, all or at least some of the transceiver 1401, the memory 1402, and the processor 1403 may be implemented in the form of a single chip.

[0421] In an embodiment, the transceiver 1401 can transmit / receive signals with a base station. The above-mentioned signals may include control information and data. To this end, the transceiver 1401 may include an RF transmitter configured to up-convert and amplify the frequency of the transmission signal, an RF receiver configured to low-noise amplify the received signal and down-convert its frequency, etc. In addition, the transceiver 1401 can receive a signal through a radio channel, output it to the processor 1403, and transmit a signal output from the processor 1403 through a radio channel.

[0422] In an embodiment, the memory 1402 may store programs and data required for UE operation. In addition, the memory 1402 may store control information or data included in a signal transmitted / received by the UE. The memory 1402 may include a storage medium such as a ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. In addition, the memory 1402 may include a plurality of memories. According to an embodiment, the memory 1402 may store a program for performing channel state information measurement and reporting operations of the UE.

[0423] In an embodiment, the processor 1403 may control a series of processes so that the UE may operate according to the above-mentioned embodiments of the present disclosure. In an embodiment, the processor 1403 may execute a program stored in the memory 1402 to receive configuration information for channel state information measurement from a base station, and based on the configuration information, control the channel state information measurement and reporting operation.

[0424] Fig.15 is a block diagram showing the structure of a base station according to an embodiment of the present disclosure.

[0425] refer to Fig.15 , the base station may include a transceiver 1501, a memory 1502, and a processor 1503. However, the components of the base station are not limited to the above examples. For example, the base station may include a greater or lesser number of components than the above components. In addition, the transceiver 1501, the memory 1502, and the processor 1503 may be implemented in the form of a single chip.

[0426] In an embodiment, the transceiver 1501 can transmit / receive signals with the UE. These signals may include control information and data. To this end, the transceiver 1501 may include an RF transmitter configured to up-convert and amplify the frequency of the transmission signal, an RF receiver configured to low-noise amplify the received signal and down-convert its frequency, etc. In addition, the transceiver 1501 can receive a signal through a radio channel, output it to the processor 1503, and transmit a signal output from the processor 1503 through a radio channel.

[0427] In an embodiment, the memory 1502 may store programs and data required for base station operation. In addition, the memory 1502 may store control information or data included in a signal transmitted / received by the base station. The memory 1502 may include a storage medium such as a ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. In addition, the memory 1502 may include a plurality of memories. According to an embodiment, the memory 1502 may store a program for performing a channel state information reporting operation of a UE.

[0428] In an embodiment, the processor 1503 may control a series of processes so that the base station may operate according to the above-mentioned embodiment. In an embodiment, the processor 1503 may execute a program stored in the memory 1502 to transmit configuration information for channel state information measurement to the UE and control the channel state information receiving operation.

[0429] The methods disclosed in the claims and / or the methods according to the embodiments described in the present disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0430] When these methods are 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 within an electronic device. At least one program includes instructions that cause an electronic device to perform methods according to various embodiments of the present disclosure as defined by the appended claims and / or disclosed herein.

[0431] These programs (software modules or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk storage device, compact disk-ROM (CD-ROM), digital versatile disk (DVD) or other types of optical storage devices, or cassette tapes. Or, any combination of some or all of them can form a memory for storing programs. In addition, multiple such memories may be included in the electronic device.

[0432] In addition, the program 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 area network (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.

[0433] 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 the convenience of description, the singular form or the plural form is appropriately selected as the presented situation, and the present disclosure is not limited to the elements expressed in the singular or plural. Therefore, the elements expressed in the plural may also include a single element, or the elements expressed in the singular may also include multiple elements.

[0434] The embodiments of the present disclosure described and shown in the specification and the drawings are merely specific examples, which are presented to easily explain the technical content of the embodiments of the present disclosure and help understand the embodiments of the present disclosure, and are not intended to limit the scope of the embodiments of the present disclosure. That is, it is obvious to those skilled in the art that other variations based on the technical ideas of the present disclosure can be implemented. In addition, the above-mentioned various embodiments can be used in combination as needed. For example, a part of an embodiment of the present disclosure can be combined with a part of another embodiment to operate a base station and a terminal. In addition, the embodiments of the present disclosure can be applied to other communication systems, and other variations based on the technical ideas of the embodiments can also be implemented. For example, the embodiments can be applied to LTE, 5G or NR systems.

Claims

1. A method performed by a terminal in a communication system, the method comprising: receiving, from a base station, a bitmap indicating subbands to be used for channel state information (CSI) reporting; generating CSI based on one or more subbands for the CSI report identified based on the bitmap; as well as transmitting the CSI to the base station, The one or more sub-bands are identified using a first method or a second method for identifying the one or more sub-bands by interpreting the bitmap.

2. The method according to claim 1, wherein: Each bit of the bitmap indicates whether a subband including a specific number of physical resource blocks (PRBs) corresponding to each bit is considered for the CSI report, wherein the first method is a method of assigning subband indexes to subbands starting from a low frequency band corresponding to each bit configured as "1" in the bitmap, and the second method is a method of assigning subband indexes to all subbands starting from a lowest frequency band, and Even in the case where the bitmap is interpreted according to the first method or the second method, the bitmap indicates the same frequency band corresponding to the odd-numbered subbands and the same frequency band corresponding to the even-numbered subbands.

3. The method according to claim 1, further comprising transmitting terminal capability information related to a subband indexing method for the CSI report to the base station, in, The terminal capability information is related to the first method or the second method for identifying the one or more subbands based on the bitmap, or a release version of the terminal.

4. The method according to claim 1, wherein: In case that the terminal corresponds to Release 17, the one or more subbands are identified by interpreting the bitmap using the first method.

5. A method performed by a base station in a communication system, the method comprising: Transmitting a bitmap indicating subbands used for channel state information CSI reporting to a terminal; as well as receiving CSI from the terminal, wherein the CSI is based on one or more subbands indicated by the bitmap for the CSI report, and The one or more sub-bands are identified using a first method or a second method for identifying the one or more sub-bands by interpreting the bitmap.

6. The method according to claim 5, wherein: Each bit of the bitmap indicates whether a subband including a specific number of physical resource blocks (PRBs) corresponding to each bit is considered for the CSI report, wherein the first method is a method of assigning subband indexes to subbands starting from a low frequency band corresponding to each bit configured as "1" in the bitmap, and the second method is a method of assigning subband indexes to all subbands starting from a lowest frequency band, and Even in the case where the bitmap is interpreted according to the first method or the second method, the bitmap indicates the same frequency band corresponding to the odd-numbered subbands and the same frequency band corresponding to the even-numbered subbands.

7. The method according to claim 5, further comprising receiving terminal capability information related to a subband indexing method for the CSI report from the terminal, in, The terminal capability information is related to the first method or the second method for identifying the one or more subbands based on the bitmap, or a release version of the terminal.

8. The method according to claim 5, wherein: In a case where the terminal corresponds to Release 17, the one or more subbands are indicated by generating the bitmap using the first method.

9. A terminal in a communication system, the terminal comprising: Transceiver; and a controller configured to perform control to receive a bitmap indicating subbands for channel state information (CSI) reporting from a base station, generate CSI based on one or more subbands for the CSI reporting identified based on the bitmap, and transmit the CSI to the base station, The one or more sub-bands are identified using a first method or a second method for identifying the one or more sub-bands by interpreting the bitmap.

10. The terminal according to claim 9, wherein: Each bit of the bitmap indicates whether a subband including a specific number of physical resource blocks (PRBs) corresponding to each bit is considered for the CSI report, wherein the first method is a method of assigning subband indexes to subbands starting from a low frequency band corresponding to each bit configured as 1 in the bitmap, and the second method is a method of assigning subband indexes to all subbands starting from a lowest frequency band, and Even in the case where the bitmap is interpreted according to the first method or the second method, the bitmap indicates the same frequency band corresponding to the odd-numbered subbands and the same frequency band corresponding to the even-numbered subbands.

11. The terminal according to claim 9, wherein: The controller is further configured to perform control to transmit terminal capability information related to a subband indexing method for the CSI report to the base station, The terminal capability information is related to the first method or the second method for identifying the one or more subbands based on the bitmap, or a release version of the terminal.

12. The terminal according to claim 9, wherein: In case that the terminal corresponds to Release 17, the one or more subbands are identified by interpreting the bitmap using the first method.

13. A base station in a communication system, the base station comprising: Transceiver; and a controller configured to perform control to transmit a bitmap indicating a subband for channel state information CSI reporting to a terminal and receive CSI from the terminal, wherein the CSI is based on one or more subbands indicated by the bitmap for the CSI report, and The one or more sub-bands are identified using a first method or a second method for identifying the one or more sub-bands by interpreting the bitmap.

14. The base station according to claim 13, wherein: Each bit of the bitmap indicates whether a subband including a specific number of physical resource blocks (PRBs) corresponding to the bit is considered for the CSI report, wherein the first method is a method of assigning subband indexes to subbands starting from a low frequency band corresponding to each bit configured as 1 in the bitmap, and the second method is a method of assigning subband indexes to all subbands starting from a lowest frequency band, and Even in the case where the bitmap is interpreted according to the first method or the second method, the bitmap indicates the same frequency band corresponding to the odd-numbered subbands and the same frequency band corresponding to the even-numbered subbands.

15. The base station according to claim 13, wherein: The controller is further configured to perform control to receive terminal capability information related to a subband indexing method for the CSI report from the terminal, The terminal capability information is related to the first method or the second method for identifying the one or more subbands based on the bitmap, or a release version of the terminal.

Images