Method and device for saving power of base station in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. Specifically, the present disclosure relates to a method performed by a user equipment (UE) in a wireless communication system, the method comprising the steps of: receiving first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX) from a base station, wherein the second configuration information comprises information about the activation duration of the UE receiving the SPS PDSCH; and receiving, from the base station, at least one SPS PDSCH, from among the one or more SPS PDSCHs based on the first configuration information, excluding the SPS PDSCHs overlapping with the inactivation duration based on the second configuration information.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system (or mobile communication system), and in particular to a method and apparatus for power saving in a base station of the wireless communication system (or mobile communication system). Background Art

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services, and can be implemented not only in "sub-6 GHz" frequency bands such as 3.5 GHz, but also in "above 6 GHz" frequency bands, known as mmWave, including 28 GHz and 39 GHz. Furthermore, consideration has been given to implementing 6G mobile communication technology (referred to as a "beyond 5G system") in the terahertz (THz) frequency band (e.g., the 95 GHz to 3 THz band) in order to achieve transmission rates fifty times faster than 5G mobile communication technology and ultra-low latency one-tenth that of 5G mobile communication technology.

[0003] At the beginning of the development of 5G mobile communication technology, in order to support services and meet performance requirements related to enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine-type communications (mMTC), there were already plans for beamforming and massive MIMO for mitigating radio wave path loss and increasing radio wave transmission distance in mmWave, parameter sets supporting dynamic operation for efficient utilization of mmWave resources and time slot formats (e.g., operating with multiple subcarrier spacings), initial access technology for supporting multi-beam transmission and wideband, definition and operation of BWP (bandwidth part), new channel coding methods such as LDPC (low-density parity-check) codes for large-scale data transmission and polar codes for high-reliability transmission of control information, L2 preprocessing, and network slicing for providing dedicated networks dedicated to specific services.

[0004] Currently, discussions on improvements and performance enhancements to initial 5G mobile communication technologies are ongoing in view of the services they are to support, and there is already physical layer standardization on technologies such as: V2X (Vehicle-to-Everything), for assisting driving determination of autonomous vehicles based on information about the location and status of vehicles sent by vehicles and for enhancing user convenience; NR-U (Unlicensed New Radio); NR UE power saving; Non-Terrestrial Network (NTN), i.e., UE direct satellite communication for providing coverage in areas where communication with terrestrial networks is unavailable, and positioning technology.

[0005] Furthermore, standardization is underway for air interface architectures / protocols related to technologies such as the Industrial Internet of Things (IIoT), which supports new services through interoperability and integration with other industries; IAB (Integrated Access and Backhaul), which provides nodes for network service area expansion by supporting wireless backhaul links and access links in an integrated manner; enhanced mobility, including conditional handover and DAPS (Dual Active Protocol Stack) handover; and two-step random access, which simplifies the random access procedure (two-step RACH for NR). Standardization is also underway in the system architecture / services area for the 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software-defined networking (SDN) technologies, as well as mobile edge computing (MEC) for receiving services based on UE location. At the system architecture / service level, standardization is also underway for the following technologies: the 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software-defined networking (SDN) technologies, as well as mobile edge computing (MEC) for receiving services based on UE location.

[0006] With the commercialization of 5G mobile communication systems, the number of connected devices, which has been growing exponentially, will be connected to the communication network, and accordingly, it is expected that enhanced functionality and performance of 5G mobile communication systems and the integrated operation of connected devices will be necessary. To this end, new research is planned in the following areas: Extended Reality (XR) for efficient support of AR (augmented reality), VR (virtual reality), MR (mixed reality), etc.; 5G performance improvement and complexity reduction through the use of 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 providing coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as full-dimensional MIMO (FD-MIMO), array antennas, and massive antennas, metamaterial-based lenses and antennas for improving signal coverage in the terahertz band, and high-dimensional spatial multiplexing technologies using OAM (orbital angular momentum) and RIS (reconfigurable smart surfaces), but also full-duplex technologies for improving the frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technologies for achieving system optimization by leveraging satellites and AI (artificial intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technologies for implementing services with a complexity level that exceeds the limits of UE operating capabilities by utilizing ultra-high-performance communication and computing resources. Summary of the Invention

[0008] Technical issues

[0009] The embodiments described herein are intended to provide an apparatus and method capable of effectively providing services in a mobile communication system.

[0010] Solution to the problem

[0011] An embodiment of the present disclosure provides a method performed by a user equipment (UE) in a wireless communication system, the method including the following operations: receiving first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX) from a base station, wherein the second configuration information includes information about an activation duration for the UE to receive the SPS PDSCH; and receiving from the base station at least one SPS PDSCH out of one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH that overlaps with an inactivity duration based on the second configuration information.

[0012] An embodiment of the present disclosure provides a method performed by a base station in a wireless communication system, the method including the following operations: sending first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with a cell discontinuous transmission (DTX) to a UE, wherein the second configuration information includes information about the activation duration for the base station to send the SPS PDSCH; and sending at least one SPS PDSCH to the UE from one or more SPS PDSCHs based on the first configuration information, excluding the SPS PDSCH that overlaps with the inactivation duration based on the second configuration information.

[0013] An embodiment of the present disclosure provides a user equipment (UE) in a wireless communication system, the UE including a transceiver and a controller connected to the transceiver, wherein the controller can be configured to receive first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX) from a base station, wherein the second configuration information includes information about an activation duration for the UE to receive the SPS PDSCH, and receive from the base station at least one SPS PDSCH out of one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactivity duration based on the second configuration information.

[0014] An embodiment of the present disclosure provides a base station in a wireless communication system, the base station including a transceiver and a controller connected to the transceiver, wherein the controller can be configured to send first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX) to a UE, wherein the second configuration information includes information about an activation duration for the base station to send an SPS PDSCH, and to send at least one SPS PDSCH out of one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactivity duration based on the second configuration information, to the UE.

[0015] Advantageous Effects of the Invention

[0016] The embodiments described herein are intended to provide an apparatus and method capable of effectively providing services in a mobile communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The basic structure of the time-frequency domain in a wireless communication system according to an embodiment of the present disclosure is shown.

[0018] Figure 2 The structure of frames, subframes, and time slots in a wireless communication system according to an embodiment of the present disclosure is shown.

[0019] Figure 3 An example of bandwidth portion configuration in a wireless communication system according to an embodiment of the present disclosure is shown.

[0020] Figure 4 An example of a control resource set configuration of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure is shown.

[0021] Figure 5 The structure of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure is shown.

[0022] Figure 6 In terms of span, it is shown that in a wireless communication system according to an embodiment of the present disclosure, a UE may have multiple PDCCH monitoring opportunities within a time slot.

[0023] Figure 7 An example of base station beam allocation configured according to a transmission configuration indicator (TCI) state in a wireless communication system according to an embodiment of the present disclosure is shown.

[0024] Figure 8 An example of a method for allocating a TCI state to a PDCCH in a wireless communication system according to an embodiment of the present disclosure is shown.

[0025] Figure 9 A TCI indication medium access control (MAC) control element (CE) signaling structure for a PDCCH demodulation reference signal (DMRS) in a wireless communication system according to an embodiment of the present disclosure is shown.

[0026] Figure 10 An example of beam configuration regarding a control resource set and a search space in a wireless communication system according to an embodiment of the present disclosure is shown.

[0027] Figure 11 A method for a base station and a UE to transmit / receive data in a wireless communication system according to an embodiment of the present disclosure is shown in consideration of a downlink data channel and rate matching resources.

[0028] Figure 12 A method for selecting a receivable control resource set by a UE in a wireless communication system according to an embodiment of the present disclosure, taking priority into consideration when receiving a downlink control channel, is shown.

[0029] Figure 13 An example of an aperiodic channel state information (CSI) reporting method according to an embodiment of the present disclosure is shown.

[0030] Figure 14 An example of physical uplink shared channel (PUSCH) repetition type B transmission in a wireless communication system according to an embodiment of the present disclosure is shown.

[0031] Figure 15 The radio protocol structures of a base station and a UE in the cases of single cell, carrier aggregation, and dual connectivity according to an embodiment of the present disclosure are shown.

[0032] Figure 16 An example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to an embodiment of the present disclosure is shown.

[0033] Figure 17 An example of downlink control information (DCI) configuration for cooperative communication in a wireless communication system according to an embodiment of the present disclosure is shown.

[0034] Figure 18 The process of controlling the transmission power of a UE by a base station in a cellular system according to an embodiment of the present disclosure is shown.

[0035] Figure 19 is a diagram illustrating cycles and durations of cell DTX and cell DRX in a wireless communication system according to an embodiment of the present disclosure.

[0036] Figure 20 A method for selecting a DL SPS to be received by a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0037] Figure 21 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0038] Figure 22 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0039] Figure 23 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0040] Figure 24 This is a view showing that in a wireless communication system according to an embodiment of the present disclosure, a UE receives DCI information in a PDCCH resource in one time slot, the DCI indicates HARQ-ACK information, and the DCI indicates an indication of a PUCCH resource in another time slot in which the HARQ-ACK information is to be retransmitted.

[0041] Figure 25 The structure of a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0042] Figure 26 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0043] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0044] When describing the embodiments, descriptions related to technical contents well-known in the art and not directly related to the present disclosure will be omitted. Such omission of unnecessary descriptions is intended to prevent the main idea of ​​the present disclosure from being obscured and to convey the main idea more clearly.

[0045] 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 reference numerals are assigned to the same or corresponding elements.

[0046] The advantages and features of the present disclosure and the manner in which they are achieved will become apparent by reference to the embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments set forth below, but may be implemented in various different forms. The following embodiments are provided only to fully disclose the present disclosure and to 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, detailed descriptions of known functions or configurations incorporated herein will be omitted when it is determined that the description may make the subject matter of the present disclosure unnecessarily unclear. The terms to be described below are terms defined in consideration of the functions in the present disclosure and may differ according to the user, the user's intention or custom. Therefore, the definition of terms should be based on the content throughout the specification.

[0047] In the following description, a base station is an entity that allocates resources to a terminal and can be at least one of a gNode B, eNode B, Node B, base station (BS), wireless access unit, base station controller, and a node on a network. A terminal can include a user equipment (UE), a mobile station (MS), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing communication functions. In this disclosure, "downlink (DL)" refers to the radio link via which a base station transmits signals to a terminal, and "uplink (UL)" refers to the radio link via which a terminal transmits signals to a base station. Furthermore, in the following description, LTE or LTE-A systems may be described by way of example, but embodiments of the present disclosure may also be applied to other communication systems with similar technical backgrounds or channel types. Examples of such communication systems may include fifth-generation mobile communication technologies (5G, New Radio, and NR), which are being developed in addition to LTE-A. In the following description, "5G" may be a concept that covers existing LTE, LTE-A, and other similar services. Furthermore, based on the judgment of those skilled in the art, the present disclosure may also be applied to other communication systems with some modifications without significantly departing from the scope of this disclosure.

[0048] As will be understood herein, each block of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine, such that the instructions, when executed by the processor of the computer or other programmable data processing device, create means for implementing the functions specified in the flowchart block(s). These computer program instructions can also be stored in a computer-usable or computer-readable memory, which can direct the computer or other programmable data processing device to operate in a specific manner, such that the instructions stored in the computer-usable or computer-readable memory produce an article of manufacture comprising instruction means for implementing the functions specified in the flowchart block(s). The computer program instructions can also be loaded onto a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable data processing device, thereby producing a computer-implemented process, such that the instructions, when executed on the computer or other programmable data processing device, provide the steps for implementing the functions specified in the flowchart block(s).

[0049] In addition, each block of the flowchart illustration may represent a module, code segment, or portion that includes one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions mentioned in the blocks may not occur in the order in which they are described. For example, depending on the functions involved, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order.

[0050] 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, "unit" does not always have a meaning limited to software or hardware. A "unit" can be configured to be stored in an addressable storage medium or to execute one or more processors. Therefore, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" can be combined into a smaller number of elements or "units" or divided into a larger number of elements or "units." In addition, elements and "units" can be implemented as one or more CPUs within a reproduction device or a secure multimedia card. In addition, a "unit" in the embodiments can include one or more processors.

[0051] Wireless communication systems are evolving toward broadband wireless communication systems for providing high-speed and high-quality packet data services using communication standards such as 3GPP's High Speed ​​Packet Access (HSPA), LTE (Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's High Speed ​​Packet Data (HRPD), Ultra Mobile Broadband (UMB), IEEE 802.16e, etc., as well as typical voice-based services.

[0052] 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 via which a user equipment (UE) or mobile station (MS) transmits data or control signals to a base station (BS) (or eNode B), and the downlink refers to the radio link via which a base station transmits data or control signals to a UE. The 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 so as to avoid overlap, that is, to establish orthogonality.

[0053] As a post-LTE communication system, 5G communication systems must freely reflect the diverse requirements of users, service providers, and others, and therefore must support services that meet these requirements. Services considered in 5G communication systems include enhanced mobile broadband (eMBB) communications, massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC).

[0054] eMBB aims to provide data rates higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must provide a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink for a single base station. Furthermore, the 5G communication system must provide increased user-perceived data rates and maximum data rates to the user end user (UE). To meet these requirements, improvements in transmission and reception technologies, including further enhanced multiple-input multiple-output (MIMO) transmission technology, are required. Furthermore, the data rates required by 5G communication systems can be achieved using frequency bandwidths greater than 20 MHz in frequency bands between 3 GHz and 6 GHz, or even higher, rather than the transmission bandwidths of up to 20 MHz required to transmit signals in the 2 GHz frequency band used in LTE.

[0055] In addition, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. In order to effectively provide the IoT, mMTC has requirements such as supporting the connection of a large number of UEs in a cell, enhanced coverage of UEs, improved battery life, and reduced costs for UEs. Since the IoT provides communication functions while providing services to various sensors and various devices, it must support a large number of UEs in a cell (for example, 1,000,000 UEs / km). 2 ). In addition, UEs supporting mMTC may require wider coverage than other services provided by the 5G communication system because the UE may be located in a shadow area (such as the basement of a building) that is not covered by a cell due to the nature of the service. UEs supporting mMTC must be configured to be inexpensive and may require a very long battery life, such as 10 to 15 years, because it is difficult to frequently replace the UE's battery.

[0056] Finally, URLLC is a mission-critical cellular-based wireless communication service. For example, URLLC can be used for services such as remote control of robots or machines, industrial automation, unmanned aerial vehicles, telemedicine, and emergency alerts. Therefore, URLLC must provide communications with ultra-low latency and ultra-high reliability. For example, services supporting URLLC must meet an air interface latency of less than 0.5ms and also require 10 -5 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.

[0057] 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 the services to meet the different requirements of the corresponding services. Of course, 5G is not limited to the above three services.

[0058] [NR time-frequency resources]

[0059] Hereinafter, the frame structure of the 5G system will be described in more detail with reference to the accompanying drawings.

[0060] Figure 1 The basic structure of the time-frequency domain in a wireless communication system according to an embodiment of the present disclosure is shown.

[0061] exist Figure 1In the time-frequency domain, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time-frequency domain is a resource element (RE) 101, which can be defined as one orthogonal frequency division multiplexing (OFDM) symbol 102 on the time axis and one subcarrier 103 on the frequency axis. In the frequency domain, (eg, 12) consecutive REs may constitute one resource block (RB) 104 .

[0062] Figure 2 The structure of frames, subframes, and time slots in a wireless communication system according to an embodiment of the present disclosure is shown.

[0063] 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). =14). One 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 depending on the configured value μ of the subcarrier spacing 204 or 205. Figure 2 The example in FIG shows a case where the subcarrier spacing configuration value is μ = 0 (204) and a case where μ = 1 (205). 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, the number of time slots in each subframe is The number of slots per frame may vary depending on the subcarrier spacing configuration value μ. Can be different accordingly. and It can be defined according to each subcarrier spacing configuration μ in Table 1 below.

[0064] [Table 1]

[0065]

[0066] [Bandwidth Part (BWP)]

[0067] Next, a bandwidth part (BWP) configuration in a 5G communication system will be described in detail with reference to the accompanying drawings.

[0068] Figure 3 An example of bandwidth portion configuration in a wireless communication system according to an embodiment of the present disclosure is shown.

[0069] Figure 3An example is shown in which UE bandwidth 300 is configured to include two bandwidth parts, namely bandwidth part #1 (BWP#1) 301 and bandwidth part #2 (BWP#2) 302. The base station can configure one or more bandwidth parts for the UE and can configure the following information for each bandwidth part as given below.

[0070] [Table 2]

[0071]

[0072] Obviously, the above examples are not limiting, and in addition to the above configuration information, various parameters related to bandwidth parts may also be configured for the UE. The base station may transmit the configuration information to the UE via higher-layer signaling (e.g., radio resource control (RRC) signaling). One configured bandwidth part or at least one of multiple configured bandwidth parts may be activated. Whether a configured bandwidth part is activated may be semi-statically transmitted from the base station to the UE via RRC signaling, or dynamically transmitted to the UE via downlink control information (DCI).

[0073] According to some embodiments, before establishing a radio resource control (RRC) connection, the base station may configure an initial bandwidth part (BWP) for the UE for initial access via the Master Information Block (MIB). More specifically, the UE may receive configuration information regarding the control resource set (CORESET) and search space, which may be used to transmit the PDCCH for receiving system information (which may correspond to the remaining system information (RMSI) required for initial access or the system information block 1 (SIB1) via the MIB during the initial access procedure). Each of the CORESET and search space configured via the MIB may be considered to have an ID (ID) of 0. The base station may notify the UE of configuration information regarding CORESET #0, such as frequency allocation information, time allocation information, and parameter sets, via the MIB. Furthermore, the base station may notify the UE of configuration information regarding the listening period and timing of CORESET #0, i.e., configuration information regarding search space #0, via the MIB. The UE may consider the frequency domain configured for CORESET #0, obtained from the MIB, to be the initial bandwidth part for initial access. The ID of the initial bandwidth part may be 0.

[0074] The bandwidth-related configurations supported by 5G can be used for various purposes.

[0075] According to some embodiments, if the UE supports a bandwidth smaller than the system bandwidth, this can be supported by bandwidth fraction configuration. For example, the base station can configure the frequency location of the bandwidth fraction for the UE (configuration information 2), so that the UE can transmit / receive data at a specific frequency location within the system bandwidth.

[0076] Furthermore, according to some embodiments, a base station may configure multiple bandwidth parts for a UE to support different parameter sets. For example, to support data transmission / reception using both a 15 kHz subcarrier spacing and a 30 kHz subcarrier spacing, two bandwidth parts may be configured with subcarrier spacings of 15 kHz and 30 kHz, respectively. The different bandwidth parts may be frequency-division multiplexed (FDM), and if data is to be transmitted / received with a specific subcarrier spacing, the bandwidth part configured with the corresponding subcarrier spacing may be activated.

[0077] In addition, according to some embodiments, the base station can configure bandwidth portions with different bandwidth sizes for the UE for the purpose of reducing the power consumed by the UE. For example, if the UE supports a relatively large bandwidth, such as 100 MHz, and always sends / receives data with the corresponding bandwidth, a considerable amount of power consumption may occur. In particular, unnecessarily monitoring a downlink control channel with a large bandwidth of 100 MHz when there is no traffic may be very inefficient from the perspective of power consumption. In order to reduce the power consumed by the UE, the base station can configure a bandwidth portion with a relatively small bandwidth (for example, a bandwidth portion of 20 MHz) for the UE. The UE can perform a monitoring operation in the 20 MHz bandwidth portion when there is no traffic, and if data has occurred, it can send / receive data in the 100 MHz bandwidth portion as instructed by the base station.

[0078] In conjunction with the bandwidth part configuration method, the UE can receive configuration information about the initial bandwidth part via the MIB during the initial access step before being RRC-connected. More specifically, the UE can have a control resource set (CORESET) configured for a downlink control channel, which can be used to transmit downlink control information (DCI) from the MIB on the physical broadcast channel (PBCH) for scheduling system information blocks (SIBs). The bandwidth of the control resource set configured by the MIB can be considered the initial bandwidth part, and the UE can receive the physical downlink shared channel (PDSCH) that transmits the SIBs via the configured initial bandwidth part. The initial bandwidth part can be used not only for receiving SIBs, but also for other system information (OSI), paging, random access, etc.

[0079] [Bandwidth Part (BWP) Change]

[0080] If the UE has one or more bandwidth parts configured for it, the base station can indicate to the UE to change (or switch or transition) the bandwidth part by using the bandwidth part indicator field in the DCI. As an example, if the UE's currently activated bandwidth part is Figure 3If the bandwidth part #1 301 in the received DCI is used, the base station may indicate the bandwidth part #2 302 using the bandwidth part indicator inside the DCI, and the UE may change the bandwidth part to the bandwidth part #2 302 indicated by the bandwidth part indicator inside the received DCI.

[0081] As described above, the DCI-based bandwidth part change can be indicated by the DCI for scheduling PDSCH or PUSCH, and therefore, upon receiving the bandwidth part change request, the UE needs to be able to receive or transmit the PDSCH or PUSCH scheduled by the corresponding DCI in the changed bandwidth part without any problems. To this end, the delay time (T BWP ) requirements, and can be defined, for example, as follows.

[0082] [Table 3]

[0083]

[0084] Depending on the UE's capabilities, the bandwidth part change delay time requirement can support type 1 or type 2. The UE can report the supported bandwidth part change delay time type to the base station. If the UE receives a DCI including a bandwidth part change indicator in time slot n, then according to the above requirements on the bandwidth part change delay time, the UE can change the bandwidth part change delay time no later than time slot n+T BWP The change to the new bandwidth part indicated by the bandwidth part change indicator is completed at a time point of , and the data channel scheduled by the corresponding DCI can be sent / received in the newly changed bandwidth part. According to an embodiment, if the base station wants to schedule the data channel by using the new bandwidth part, the base station can change the delay time (T) based on the bandwidth part of the UE. BWP ) to determine the time domain resource allocation for the data channel. That is, when the base station schedules the data channel using the new bandwidth part, it can combine the method for determining the time domain resource allocation for the data channel and schedule the corresponding data channel after the bandwidth part change delay time. Therefore, the UE may not expect that the DCI indicating the bandwidth part change will indicate a time domain that is less than the bandwidth part change delay time (T BWP ) time slot offset (K0 or K2) value.

[0085] If the UE has received a DCI indicating a bandwidth fraction change (e.g., DCI format 1_1 or 0_1), the UE may not perform transmission or reception during a time interval from the third symbol of the slot for receiving the PDCCH including the corresponding DCI to the start point of the slot indicated by the slot offset (K0 or K2) value indicated by the time domain resource allocation indicator field in the corresponding DCI. For example, if the UE has received a DCI indicating a bandwidth fraction change in slot n, and if the slot offset value indicated by the corresponding DCI is K, the UE may not perform transmission or reception from the third symbol of slot n to a symbol before slot n+K (e.g., the last symbol of slot n+K-1).

[0086] [SS / PBCH block]

[0087] Next, the synchronization signal (SS) / PBCH block in 5G will be described.

[0088] The SS / PBCH block may refer to a physical layer channel block including the primary synchronization signal (PSS), the secondary synchronization signal (SSS), and the PBCH. Details are as follows.

[0089] -PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides partial information of a cell ID.

[0090] -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 for PBCH.

[0091] -PBCH: Provides MIB, which is mandatory system information required for the UE to transmit / receive data channels and control channels. Mandatory system information may include search space-related control information indicating radio resource mapping information for control channels, scheduling control information about a separate data channel for transmitting system information, etc.

[0092] -SS / PBCH block: An 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.

[0093] During the initial access phase, the UE can detect the PSS and SSS and decode the PBCH. The UE can obtain the MIB from the PBCH, and this MIB can be used to configure Control Resource Set (CORESET) #0 (which may correspond to the CORESET with a CORESET index of 0). The UE can monitor CORESET #0 by assuming that the Demodulation Reference Signal (DMRS) transmitted in the selected SS / PBCH block and CORESET #0 are quasi-co-located (QCL). The UE can receive system information containing the downlink control information transmitted in CORESET #0. From this received system information, the UE can obtain configuration information related to the Random Access Channel (RACH) required for initial access. The UE can transmit a Physical RACH (PRACH) to the base station based on the selected SS / PBCH index. Upon receiving the PRACH, the base station can obtain information about the SS / PBCH block index selected by the UE. The base station can then determine which block the UE has selected from the corresponding SS / PBCH blocks and that it is monitoring CORESET #0 associated with that block.

[0094] [PDCCH: About DCI]

[0095] Next, downlink control information (DCI) in the 5G system will be described in detail.

[0096] In 5G systems, scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) is included in DCI and transmitted from the base station to the UE via DCI. Regarding PUSCH or PDSCH, the UE can monitor both fallback DCI formats and non-fallback DCI formats. The fallback DCI format may include fixed fields predefined between the base station and the UE, while the non-fallback DCI format may include configurable fields.

[0097] The DCI may undergo channel coding and modulation processing, and then be sent through the Physical Downlink Control Channel (PDCCH) after the channel coding and modulation processing. A cyclic redundancy check (CRC) may be attached to the payload of the DCI message, and the CRC may be scrambled by the 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 command, or random access response). That is, the RNTI may not be sent explicitly, but may be sent while being included in the CRC calculation process. Upon receiving the DCI message sent through the PDCCH, the UE may use the allocated RNTI to identify the CRC, and if the CRC identification result is correct, the UE may know that the corresponding message has been sent to the UE.

[0098] For example, the DCI used to schedule the PDSCH for system information (SI) can be scrambled by the SI-RNTI. The DCI used to schedule the PDSCH for the random access response (RAR) message can be scrambled by the RA-RNTI. The DCI used to schedule the PDSCH for the paging message can be scrambled by the P-RNTI. The DCI used to notify the slot format indicator (SFI) can be scrambled by the SFI-RNTI. The DCI used to notify the transmit power control (TPC) can be scrambled by the TPC-RNTI. The DCI used to schedule the UE-specific PDSCH or PUSCH can be scrambled by the cell RNTI (C-RNTI).

[0099] 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. The DCI format 0_0 in which the CRC is scrambled by the C-RNTI may include, for example, the following information.

[0100] [Table 4]

[0101]

[0102] 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. The DCI format 0_1 ​​in which the CRC is scrambled by the C-RNTI may include, for example, the following information.

[0103] [Table 5]

[0104]

[0105]

[0106]

[0107] DCI format 1_0 may be used as a fallback DCI for scheduling PDSCH, and in this case, CRC may be scrambled by C-RNTI. DCI format 1_0 in which CRC is scrambled by C-RNTI may include, for example, the following information.

[0108] [Table 6]

[0109]

[0110] 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. The DCI format 1_1 in which the CRC is scrambled by the C-RNTI may include, for example, the following information.

[0111] [Table 7]

[0112]

[0113]

[0114] [PDCCH: CORESET, REG, CCE and search space]

[0115] Hereinafter, a downlink control channel in a 5G communication system will be described in more detail with reference to the accompanying drawings.

[0116] Figure 4 An example of a control resource set configuration of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure is shown. Figure 4 An example is shown in which a UE bandwidth portion 410 is configured along the frequency axis and two control resource sets (control resource set #1 420 and control resource set #2 401) are configured within a time slot 402 along the time axis. The control resource sets 401 and 402 may be configured in specific frequency resources 410 within the entire UE bandwidth portion 403 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. Figure 4 In the illustrated example, 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.

[0117] The control resource set in 5G can be configured for the UE by the base station through higher-layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). Configuring a control resource set for the UE involves 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 following information may be included.

[0118] [Table 8]

[0119]

[0120]

[0121] In Table 8, 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 (QCLed) with the DMRS transmitted in the corresponding control resource set. Figure 5 The structure of the downlink control channel in the wireless communication system according to the embodiment of the present disclosure is shown. 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. A REG 503 may be defined by one OFDM symbol 501 along the time axis and one physical resource block (PRB) 502 (i.e., 12 subcarriers) along the frequency axis. The base station may configure a downlink control channel allocation unit by concatenating REGs 503.

[0122] Assume that the basic unit of downlink control channel allocation in 5G is as follows Figure 5 For example, a control channel element 504 is shown, and a CCE 504 may include multiple REGs 503. Figure 5 , for example, the REG 503 may include 12 REs, and if one CCE 504 includes six REGs 503, then one CCE 504 may include 72 REs. A downlink control resource set may include multiple CCEs 504 once configured, 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. The CCEs 504 in the control resource set may be distinguished by number, and the number of CCEs 504 may be allocated according to a logical mapping scheme.

[0123] Figure 5 The basic unit of the downlink control channel shown, ie, REG 503, may include both the RE to which the DCI is mapped and the region to which the reference signal (DMRS 505) for decoding the RE is mapped. Figure 5 As shown, three DRMSs 503 can be sent within one REG 505. Depending on the aggregation level (AL), the number of CCEs required to send 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 sent through L CCEs. The UE needs to detect the signal without information about the downlink control channel, and therefore a search space indicating a set of CCEs has been defined for blind decoding. The search space is a set of downlink control channel candidates including CCEs that the UE needs to attempt to decode at a given AL, and because 1, 2, 4, 8 or 16 CCEs can constitute 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.

[0124] Search spaces can be classified into common search spaces and UE-specific search spaces. 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 sending 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 the common search space can therefore be defined as a predetermined 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 UE-specifically defined as a function of various system parameters and the identity of the UE.

[0125] In 5G, the parameters of the PDCCH search space can be configured by the base station for the UE through upper layer signaling (e.g., SIB, MIB, or RRC 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 of the search space, the monitoring timing of each symbol in the time slot associated with 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 used to monitor the search space. For example, the following information may be included.

[0126] [Table 9]

[0127]

[0128]

[0129]

[0130] Based on the configuration information, the base station may configure one or more search space sets for the UE. According to some embodiments, 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 in the common search space in search space set 1, and may configure DCI format B scrambled by Y-RNTI in the UE-specific search space in search space set 2. Based on the configuration information, one or more search space sets may exist in the common search space or the UE-specific search space. For example, search space set #1 and search space set #2 may be configured as common search spaces, and search space set #3 and search space set #4 may be configured as UE-specific search spaces.

[0131] The following combinations of DCI formats and RNTIs may be monitored in the common search space.

[0132] -DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0133] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0134] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0135] -DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0136] -DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0137] The following combinations of DCI formats and RNTIs may be monitored in the UE-specific search space.

[0138] -DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0139] -DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0140] The enumerated RNTIs may follow the definitions and usage given below.

[0141] Cell RNTI (C-RNTI): used to schedule UE-specific PDSCH

[0142] Temporary cell RNTI (TC-RNTI): used to schedule UE-specific PDSCH

[0143] Configured Scheduling RNTI (CS-RNTI): used to schedule semi-statically configured UE-specific PDSCH

[0144] Random Access RNTI (RA-RNTI): used to schedule PDSCH in the random access step

[0145] Paging RNTI (P-RNTI): used to schedule the PDSCH in which paging is sent

[0146] System Information RNTI (SI-RNTI): used to schedule the PDSCH in which system information is sent

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

[0148] Transmit power control for PUSCH RNTI (TPC-PUSCH-RNTI): used to indicate power control commands for PUSCH

[0149] Transmit power control for PUCCH RNTI (TPC-PUCCH-RNTI): used to indicate power control commands for PUCCH

[0150] Transmit Power Control for SRS RNTI (TPC-SRS-RNTI): used to indicate power control commands for SRS

[0151] The DCI formats listed above may follow the definitions given below.

[0152] [Table 10]

[0153]

[0154] In 5G, the search space at the aggregation level L associated with the control resource set p and the search space set s can be expressed by the following Equation 1.

[0155] [Equation 1]

[0156]

[0157] -L: aggregation level

[0158] - : Carrier index

[0159] - : Controls the total number of CCEs in resource set p

[0160] - : time slot index

[0161] - : The number of PDCCH candidates at aggregation level L

[0162] - = 0, ..., -1: PDCCH candidate index at aggregation level L

[0163] - = 0, ..., -1

[0164] - , , , , ,

[0165] - :UE ID

[0166] In the case of a public search space, The value may correspond to 0.

[0167] In case of UE specific search space, The value may correspond to a value changed by the UE's identity (C-RNTI or an ID configured by the base station for the UE) and a time index.

[0168] In 5G, multiple search space sets can be configured with different parameters (e.g., the parameters in Table 10), and the search space set set that the UE monitors at each time point can be different accordingly. For example, if search space set #1 is configured with an X time slot period, if search space set #2 is configured with a Y time slot period, and if X and Y are different, the UE can monitor both search space set #1 and search space set #2 in a specific time slot, and can monitor one of search space set #1 and search space set #2 in another specific time slot.

[0169] [PDCCH: span]

[0170] Regarding the case where the UE has multiple PDCCH monitoring opportunities within a time slot, the UE can perform UE capability reporting at each subcarrier spacing, and the concept of "span" can be used in this regard. The span refers to the consecutive symbols configured so that the UE can monitor the PDCCH within the time slot, and each PDCCH monitoring opportunity is within a span. The span can be represented by (X, Y), where X refers to the minimum number of symbols between the first symbols of two consecutive spans, and Y refers to the number of consecutive symbols in which the PDCCH can be monitored within a span. Here, the UE can monitor the PDCCH within a range of Y symbols starting from the first symbol of the span within the span.

[0171] Figure 5 B shows the case where a UE can have multiple physical downlink control channel (PDCCH) monitoring opportunities within a time slot in a wireless communication system according to an embodiment of the present disclosure in terms of span. Possible spans are (X, Y) = (7, 3), (4, 3), (2, 2), and these three cases can be represented by Figure 6, "6-00," "6-05," and "6-10" in the time slot. As an example, "6-00" may describe a case where two spans described by (7, 4) exist within a time slot. The interval between the first symbols of the two spans is described as X=7, the PDCCH monitoring opportunities may exist within a total of Y=3 symbols starting from the first symbol of each span, and search spaces 1 and 2 may exist within Y=3 symbols, respectively. As another example, "6-05" may describe a case where a total of three spans described by (4, 3) exist within a time slot, and the second and third spans are separated by X'=5 symbols, which is greater than X=4.

[0172] [PDCCH: UE capability report]

[0173] The slot positions of the common search space and UE-specific search space are indicated by the parameter "monitoringSymbolsWitninSlot" in Table 13-1, and the symbol positions within the slot are indicated as a bitmap by the parameter "monitoringSymbolsWitninSlot" in Table 9. At the same time, the symbol positions within the slots where the UE can monitor the search space can be reported to the base station through the following UE capabilities.

[0174] -UE capability 1 (hereinafter referred to as FG 3-1). This UE capability may have the following meaning: if there is one monitoring opportunity (MO) for type 1 and type 3 common search spaces or UE-specific search spaces in a time slot, as shown in Table 11 below, then the UE may monitor the corresponding MO when the corresponding MO is located within the first three symbols in the time slot. This UE capability is a mandatory capability supported by all UEs supporting NR, and whether this UE capability is supported is not explicitly reported to the base station.

[0175] [Table 11]

[0176]

[0177]

[0178]

[0179] -UE capability 2 (hereinafter referred to as FG 3-2). This UE capability has the following meaning: if there is a monitoring opportunity (MO) for the common search space or UE-specific search space within a time slot, as shown in Table 12 below, the UE can monitor the corresponding MO, regardless of the starting symbol position of the corresponding MO. This UE capability is optionally supported by the UE, and whether it is supported is explicitly reported to the base station.

[0180] [Table 12]

[0181]

[0182] -UE Capability 3 (hereinafter referred to as FG 3-5, 3-5a, or 3-5b). This UE capability has the following meaning: If multiple monitoring opportunities (MOs) exist within a slot for a common search space or a UE-specific search space, as shown in Table 13 below, this indicates the pattern of MOs that the UE can monitor. The pattern includes the interval X between the start symbols of different MOs and the maximum symbol length Y for a single MO. The (X, Y) combinations supported by the UE can be one or more of {(2, 2), (4, 3), (7, 3)}. This UE capability is optionally supported by the UE, and support for this UE capability and the aforementioned (X, Y) combinations is explicitly reported to the base station.

[0183] [Table 13]

[0184]

[0185]

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197] The UE can report to the base station whether it supports the above-mentioned capability 2 and / or capability 3 and related parameters. The base station can allocate time domain resources to the common search space and the UE-specific search space based on the UE capability report. During resource allocation, the base station can ensure that the MO is not located in a position where the UE cannot monitor it.

[0198] [QCL, TCI status]

[0199] In a wireless communication system, one or more different antenna ports (which may be replaced by one or more channels, signals, or combinations thereof, but for convenience in the following description of this disclosure, will be collectively referred to as different antenna ports) can be associated with each other via a quasi-co-location (QCL) configuration as shown in Table 14 below. The TCI state is used to declare the QCL relationship between a PDCCH (or PDCCH DRMS) and another RS ​​or channel. The description of a reference antenna port A (reference RS#A) and a target antenna port B (target RS#B) being in QCL with each other allows the UE to apply some or all of the large-scale channel parameters estimated for antenna port A to the channel measurement from antenna port B. QCL needs to be associated with different parameters depending on the situation, such as 1) time tracking affected by average delay and delay spread, 2) frequency tracking affected by Doppler shift and Doppler spread, 3) radio resource management (RRM) affected by average gain, or 4) beam management (BM) affected by spatial parameters. Therefore, as shown in Table 3 below, four types of QCL relationships are supported in NR.

[0200] [Table 14]

[0201]

[0202] Spatial RX parameters may refer to some or all of various parameters as a whole, such as angle of arrival (AoA), power angular spectrum (PAS) of AoA, angle of departure (AoD), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, and spatial channel correlation.

[0203] The QCL relationship can be configured for the UE using the RRC parameters TCI-state and QCL-info as shown in Table 15 below. Referring to Table 15, the base station can configure one or more TCI states for the UE, thereby notifying the UE of up to two QCL relationships (qcl-Type1, qcl-Type2) for the RS (i.e., target RS) with an ID referenced to the TCI state. Each piece of QCL information (QCL-Info) included in each TCI state includes the serving cell index and BWP index of the reference RS indicated by the corresponding QCL information, the type and ID of the reference RS, and the QCL type as shown in Table 14 above.

[0204] [Table 15]

[0205]

[0206]

[0207] Figure 7An example of base station beam allocation according to a transmission configuration indicator (TCI) state configuration in a wireless communication system according to an embodiment of the present disclosure is shown. Figure 7 , the base station can transmit information about N different beams to the UE through N different TCI states. Figure 7 In the case of N=3 shown, the base station can configure the qcl-Type2 parameters in the three TCI states 700, 705, and 710 included in QCL type D to be associated with CSI-RSs or SSBs corresponding to different beams, thereby notifying the antenna ports referring to different TCI states 700, 705, and 710 that are associated with different spatial Rx parameters (i.e., different beams). Tables 16 to 20 below list valid TCI state configurations based on the target antenna port type.

[0208] Table 16 lists the valid TCI state configurations when the target antenna port is a tracking CSI-RS (TRS). A TRS is an NZP CSI-RS with no repetition parameter configured in the CSI-RS and trs-Info configured as "true." In Table 16, configuration 3 can be used for aperiodic TRS.

[0209] [Table 16] Valid TCI state configuration when the target antenna port is CSI-RS (TRS) for tracking

[0210] [Table 16]

[0211]

[0212] Table 17 lists the valid TCI state configurations when the target antenna port is the CSI-RS of the CIS. The CSI-RSTRS of the CSI refers to the NZP CSI-RS for which no parameter indicating repetition (e.g., repetition parameter) is configured in the CSI-RS and its trs-Info is not configured as "true".

[0213] [Table 17] Valid TCI state configuration when the target antenna port is CSI-RS of CSI

[0214] [Table 17]

[0215]

[0216] Table 18 lists the valid TCI state configurations when the target antenna port is a CSI-RS for beam management (BM) (which has the same meaning as the CSI-RS for L1RSRP reporting). The CSI-RS for BM refers to an NZP CSI-RS with a repetition parameter configured to have a value of "on" or "off" in the CSI-RS and whose trs-Info is not configured to be "true".

[0217] [Table 18] Valid TCI state configuration when the target antenna port is CSI-RS for BM (for L1 RSRP reporting)

[0218] [Table 18]

[0219]

[0220] Table 19 lists the valid TCI state configurations when the target antenna port is PDCCH DMRS

[0221] [Table 19] Valid TCI state configuration when the target antenna port is PDCCH DMRS

[0222] [Table 19]

[0223]

[0224] Table 20 lists the valid TCI state configurations when the target antenna port is PDSCH DMRS.

[0225] [Table 20] Valid TCI state configuration when the target antenna port is PDSCH DMRS

[0226] [Table 20]

[0227]

[0228] According to the representative QCL configuration method based on Tables 16 to 20 above, the target antenna port and reference antenna port in each step are configured and operated as "SSB" -> "TRS" -> "CSI-RS for CSI, or CSI-RS for BM, or PDCCH DMRS, or PDSCH DMRS." Therefore, it is possible to assist the UE's reception operation by associating statistical characteristics that can be measured from the SSB and TRS with the corresponding antenna ports.

[0229] [PDCCH: About TCI status]

[0230] The specific TCI state combinations applicable to PDCCH DMRS antenna ports can be given in the following Table 21. The fourth row in Table 21 corresponds to the combination assumed by the UE before RRC configuration and is not possible to configure after RRC.

[0231] [Table 21]

[0232]

[0233] Figure 8 An example of a method for allocating TCI states to PDCCHs in a wireless communication system according to an embodiment of the present disclosure is shown. In NR, for dynamic allocation of PDCCH beams, the following is supported: Figure 8 The layered signaling method shown in Figure 2. Figure 8 , the base station may configure N TCI states 805, 810, ..., 820 for the UE through RRC signaling 800, and may configure some of these states as TCI states for the CORESET (825). The base station may then indicate one of the TCI states 830, 835, and 840 for the CORESET to the UE through medium access control (MAC) control element (CE) signaling (845). The UE may then receive the PDCCH based on the beam information included in the TCI state indicated by the MAC CE signaling.

[0234] Figure 9 A TCI indication medium access control (MAC) control element (CE) signaling structure for a PDCCH demodulation reference signal (DMRS) in a wireless communication system according to an embodiment of the present disclosure is shown.

[0235] refer to Figure 9 , TCI indication MAC CE signaling for PDCCH DMRS can be configured by 2 bytes (16 bits) and includes a 5-bit serving cell ID 915 , a 4-bit CORESET ID 920 , and a 7-bit TCI state ID 925 .

[0236] Figure 10 An example of beam configuration regarding a control resource set and a search space in a wireless communication system according to an embodiment of the present disclosure is shown. Figure 10, the base station can indicate one of the TCI state lists included in the CORESET 1000 configuration through MAC CE signaling (1005). Before different TCI states are indicated for the corresponding CORESET through different MAC CE signaling, the UE can assume that the exact same QCL information (beam #1) 1005 is applied to all one or more search spaces 1010, 1015, and 1020 connected to the CORESET. The above-mentioned PDCCH beam allocation method has the following problems: it is difficult to indicate beam changes faster than the MAC CE signaling delay, and the same beam is unidirectionally applied to each CORESET regardless of the search space characteristics, making flexible PDCCH beam operation difficult. The following embodiments of the present disclosure provide more flexible PDCCH beam configuration and operation methods. Although a number of different examples will be provided for the convenience of describing the embodiments of the present disclosure, they are not mutually exclusive and can be appropriately combined and applied for each situation.

[0237] The base station can configure one or more TCI states for a specific control resource set for the UE and can activate one of the configured TCI states through a MAC CE activation command. For example, if {TCI state #0, TCI state #1, TCI state #2} are configured as the TCI states for control resource set #1, the base station can send an activation command to the UE through a MAC CE, so that TCI state #0 is assumed to be the TCI state for control resource set #1. Based on the activation command for the TCI state received through the MAC CE, the UE can correctly receive the DMRS of the corresponding CORESET based on the QCL information in the activated TCI state.

[0238] For a control resource set with a configured index of 0 (control resource set #0), if the UE fails to receive a MAC CE activation command regarding the TCI state of control resource set #0, the UE may assume that the DMRS sent in CORESET #0 has utilized the SS / PBCH block QCL identified during the initial access procedure or in a non-contention-based random access procedure not triggered by a PDCCH command.

[0239] For a control resource set (CORESET#X) with a configured index value other than 0, if the UE has no TCI state configured for CORESET#X, or if the UE has one or more TCI states configured for it but fails to receive a MAC CE activation command to activate one of the TCI states, the UE may assume that the DMRS transmitted in CORESET#X is already QCLed with the SS / PBCH block identified during the initial access procedure.

[0240] [PDCCH: About QCL prioritization rules]

[0241] Hereinafter, an operation for determining the QCL priority with respect to the PDCCH will be described in detail.

[0242] If, in a specific PDCCH monitoring opportunity, multiple control resource sets operating according to carrier aggregation within a single cell or frequency band and existing in the activated bandwidth portion within a single or multiple cells overlap in time and have the same or different QCL type characteristics, the UE can select a specific control resource set based on the QCL priority determination operation and can monitor the control resource set with the same QCL-TypeD characteristics as the corresponding control resource set. That is, if multiple control resource sets overlap in time, only one QCL-TypeD characteristic can be received. The QCL priority can be determined by the following criteria.

[0243] - Criterion 1. The control resource set connected to the common search space has the lowest index within the cell corresponding to the lowest index in the cell including the common search space

[0244] - Criterion 2. The control resource set connected to the UE-specific search space has the lowest index within the cell corresponding to the lowest index in the cell including the UE-specific search space

[0245] As described above, if one criterion in the standard is not met, the next criterion may be applied. For example, if control resource sets overlap in time during a specific PDCCH monitoring opportunity, and if all control resource sets are not connected to a common search space but to a UE-specific search space (e.g., if criterion 1 is not met), the UE may omit the application of criterion 1 and apply criterion 2.

[0246] If a control resource set is selected according to the above criteria, the UE may additionally consider two aspects regarding the QCL information configured for the control resource set. First, if control resource set 1 has CSI-RS1 as a reference signal with a QCL-TypeD relationship, if this CSI-RS1 has a QCL-TypeD relationship with reference signal SSB1, and if another control resource set 2 has a QCL-TypeD relationship with reference signal SSB1, then the UE may consider that the two control resource sets 1 and 2 have different QCL-TypeD characteristics. Second, if control resource set 1 has CSI-RS1 as a reference signal with a QCL-TypeD relationship configured for cell 1, if this CSI-RS1 has a QCL-TypeD relationship with reference signal SSB1, if control resource set 2 has a QCL-TypeD relationship with reference signal CSI-RS2 configured for cell 2, and if this CSI-RS2 has a QCL-TypeD relationship with the same reference signal SSB1, then the UE may consider that the two control resource sets have the same QCL-TypeD characteristics.

[0247] Figure 12A method is shown for selecting a receivable control resource set by a UE in a wireless communication system according to an embodiment of the present disclosure, taking priority into consideration when receiving a downlink control channel. As an example, the UE may be configured to receive multiple control resource sets that overlap in time during a specific PDCCH monitoring opportunity 1210. These multiple control resource sets may be connected to a common search space or UE-specific search spaces for multiple cells. During the corresponding PDCCH monitoring opportunity, control resource set 1200 connected to common search space 1 may be present in bandwidth portion 1215 of cell 1, and control resource set 1205 connected to common search space 1 and control resource set 2 1220 connected to UE-specific search space 2 may be present in bandwidth portion 1225 of cell 2. Control resource sets 1215 and 1220 may have a QCL-Type D relationship with CSI-RS resource 11 configured in bandwidth portion 1 of cell 1, and control resource set 1225 may have a QCL-Type D relationship with CSI-RS resource 11 configured in bandwidth portion 1 of cell 2. If criterion 1 is applied to the corresponding PDCCH listening opportunity 1210, all other control resource sets having reference signals of the same QCL-Type D as control resource set 1215 may be received. Therefore, the UE may receive control resource sets 1210 and 1215 in the corresponding PDCCH listening opportunity 1220. As another example, the UE may be configured to receive multiple control resource sets that overlap in time in a specific PDCCH listening opportunity 1240, and such multiple control resource sets may be connected to a common search space or UE-specific search spaces for multiple cells. In the corresponding PDCCH listening opportunity, control resource set 1230 connected to UE-specific search space 1 and control resource set 2 1245 connected to UE-specific search space 2 may be present in bandwidth part 1 1250 of cell 1, and control resource set 1235 connected to UE-specific search space 1 and control resource set 2 1255 connected to UE-specific search space 3 may be present in bandwidth part 1 1260 of cell 2. Control resource sets 1245 and 1250 may have a QCL-TypeD relationship with CSI-RS resource number 1 configured in bandwidth part number 1 of cell number 1, control resource set 1255 may have a QCL-TypeD relationship with CSI-RS resource number 1 configured in bandwidth part number 1 of cell number 2, and control resource set 1260 may have a QCL-TypeD relationship with CSI-RS resource number 2 configured in bandwidth part number 1 of cell number 2. If criterion 1 is applied to the corresponding PDCCH monitoring opportunity 1240, there is no common search space, and thus the next criterion, i.e., criterion 2, may be applied.If criterion 2 is applied to the corresponding PDCCH monitoring opportunity 1240 , all other control resource sets having reference signals of the same QCL-Type D as control resource set 1 1245 may be received. Therefore, the UE may receive control resource sets 1240 and 1245 in the corresponding PDCCH monitoring opportunity 1250 .

[0248] [About rate matching / puncturing]

[0249] Hereinafter, the rate matching operation and the puncturing operation will be described in detail.

[0250] If the time and frequency resource A for transmitting symbol sequence A overlaps with the time and frequency resource B, the rate matching or puncturing operation can be regarded as an operation for transmitting / receiving channel A, taking into account resource C (the area where resource A and resource B overlap). The specific operation can be described as follows.

[0251] Rate matching operation

[0252] - The base station may transmit channel A after mapping channel A only to the remaining resource region excluding resource C (region-overlapping resource B) in the entire resource A to be used to transmit the symbol sequence A to the UE. For example, if symbol sequence A is configured as {symbol #1, symbol #2, symbol #3, symbol #4}, if resource A is {resource #1, resource #2, resource #3, resource #4}, and if resource B is {resource #3, resource #5}, the UE may receive symbol sequence A based on the assumption that it has been continuously mapped to the remaining resources {resource #1, resource #2, resource #4} excluding {resource #3} (corresponding to resource C) in resource A. Therefore, the base station may transmit the symbol sequence {symbol #1, symbol #2, symbol #3} after mapping the symbol sequence {symbol #1, symbol #2, symbol #3} to {resource #1, resource #2, resource #4}, respectively.

[0253] The UE can evaluate resource A and resource B based on scheduling information regarding symbol sequence A from the base station, thereby evaluating resource C (the region where resource A and resource B overlap). The UE can receive symbol sequence A based on the assumption that symbol sequence A has been mapped and transmitted throughout the remaining region of resource A, excluding resource C. For example, if symbol sequence A is configured as {symbol #1, symbol #2, symbol #3, symbol #4}, if resource A is {resource #1, resource #2, resource #3, resource #4}, and if resource B is {resource #3, resource #5}, the UE can receive symbol sequence A based on the assumption that it has been continuously mapped to the remaining resources {resource #1, resource #2, resource #4}, excluding {resource #3} (corresponding to resource C) within resource A. Therefore, the UE can perform a series of subsequent reception operations based on the assumption that the symbol sequence {symbol #1, symbol #2, symbol #3} has been transmitted after being mapped to {resource #1, resource #2, resource #4}, respectively.

[0254] Punching operation

[0255] If resource C (region overlapping resource B) exists within the entire resource A for transmitting symbol sequence A to the UE, the base station may map symbol sequence A to the entire resource A, but may not perform transmission in the resource region corresponding to resource C, and may perform transmission only with respect to the remaining resource regions other than resource C in resource A. For example, if symbol sequence A is configured as {symbol #1, symbol #2, symbol #3, symbol #4}, and resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the base station may map the symbol sequence {symbol #1, symbol #2, symbol #3, symbol #4} to resource A {resource #1, resource #2, resource #4}, respectively, and may transmit only the symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to the remaining resources {resource #1, resource #2, resource #4) in resource A except {resource #3} (corresponding to resource C), and may not transmit {symbol #3} mapped to {resource #3} (corresponding to resource C). Therefore, the base station can transmit the symbol sequence {symbol #1, symbol #2, symbol #4} after mapping the symbol sequence {symbol #1, symbol #2, symbol #4} to {resource #1, resource #2, resource #4}, respectively.

[0256] The UE can evaluate resource A and resource B based on scheduling information from the base station regarding symbol sequence A, thereby estimating resource C (the region where resource A and resource B overlap). The UE can receive symbol sequence A based on the assumption that symbol sequence A is mapped to the entire resource A but is transmitted only in the remaining region of resource region A excluding resource C. For example, if symbol sequence A is configured as {symbol #1, symbol #2, symbol #3, symbol #4}, if resource A is {resource #1, resource #2, resource #3, resource #4}, and if resource B is {resource #3, resource #5}, the UE may assume that symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} is mapped to resource A {resource #1, resource #2, resource #4}, respectively, but {symbol #3} mapped to {resource #3} (corresponding to resource C) is not transmitted. Based on the assumption that the symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to the remaining resources {resource #1, resource #3, resource #4} in resource A, excluding {resource #3} (corresponding to resource C), has been mapped and transmitted, the UE may receive the symbol sequence. Therefore, the UE may perform a series of subsequent reception operations based on the assumption that the symbol sequence {symbol #1, symbol #2, symbol #4} has been transmitted after being mapped to {resource #1, resource #2, resource #4}, respectively.

[0257] Hereinafter, we will describe a method for configuring rate matching resources for rate matching purposes in a 5G communication system. Rate matching refers to adjusting the size of a signal based on the amount of resources available to transmit the signal. For example, data channel rate matching can mean that the data channel is not mapped and transmitted with respect to a specific time and frequency resource domain, and the size of the data is adjusted accordingly.

[0258] Figure 11 A method for transmitting / receiving data by a base station and a UE in a wireless communication system according to an embodiment of the present disclosure in consideration of a downlink data channel and rate matching resources is shown.

[0259] Figure 11A downlink data channel (PDSCH) 1101 and rate-matching resources 1102 are shown. A base station can configure one or more rate-matching resources 1102 for a UE through higher-layer signaling (e.g., RRC signaling). The rate-matching resource 1102 configuration information may include time-domain resource allocation information 1103, frequency-domain resource allocation information 1104, and period information 1105. Hereinafter, the bitmap corresponding to the frequency-domain resource allocation information 1104 is referred to as the "first bitmap," the bitmap corresponding to the time-domain resource allocation information 1103 is referred to as the "second bitmap," and the bitmap corresponding to the period information 1105 is referred to as the "third bitmap." If all or some of the time and frequency resources of the scheduled PDSCH 1101 overlap with the configured rate-matching resources 1102, the base station may rate-match and transmit the PDSCH 1101 in the rate-matching resource 1102 portion, and the UE may receive and decode the PDSCH 1101 assuming that the PDSCH 1101 has been rate-matched in the rate-matching resource 1102 portion.

[0260] The base station can dynamically notify the UE via DCI whether the PDSCH will be rate-matched within the configured rate-matching resource portion through an additional configuration (e.g., corresponding to the "rate matching indicator" within the DCI format described above). Specifically, the base station can select some of the configured rate-matching resources and group them into rate-matching resource groups. The base station can also use a bitmap type to indicate to the UE via DCI whether the PDSCH is rate-matched for each rate-matching resource group. For example, if four rate-matching resources (RMR#1, RMR#2, RMR#3, and RMR#4) are configured, the base station can configure rate-matching group RMG#1 = {RMR#1, RMR#2} and RMG#2 = {RMR#3, RMR#4}. The base station can then use a bitmap to indicate to the UE whether rate matching will occur in RMG#1 and RMG#2, respectively, using two bits within the DCI field. For example, if rate matching is to be performed, the base station can indicate this using a "1," and if not, the base station can indicate this using a "0."

[0261] 5G supports "RB symbol level" and "RE level" granularity as methods for configuring the above-mentioned rate matching resources of the UE. More specifically, the following configuration method can be followed.

[0262] RB symbol level

[0263] The UE may configure up to four RateMatchPattern per bandwidth part through upper layer signaling, and one RateMatchPattern may include the following contents.

[0264] Reserved resources within a bandwidth portion may include resources in the time and frequency resource domains, with corresponding reserved resources configured as a combination of an RB level bitmap and a symbol level bitmap in the frequency domain. Reserved resources may span one or two time slots. A time domain pattern (periodicityAndPattern) may also be configured, where the corresponding RB level and symbol level bitmap pairs are repeated in the time and frequency domains.

[0265] -It may include a resource region corresponding to a time domain pattern configured by time domain and frequency domain resource regions configured by a CORESET within a bandwidth part, and a search space configuration that repeats the corresponding resource region.

[0266] RE Level

[0267] The UE can configure the following contents through upper layer signaling.

[0268] - Information about the configuration of REs corresponding to the LTE CRS (cell-specific reference signal or common reference signal) pattern (lte-CRS-ToMatchAround), which may include the LTE CRS port number (nrofCRS-Ports) and LTE-CRS-vshift value (v-shift), the position information of the center subcarrier of the LTE carrier from the reference frequency point (e.g., reference point A) (carrierFreqDL), the bandwidth size of the LTE carrier (carrierBandwidthDL), the subframe configuration information corresponding to the Multicast Broadcast Single Frequency Network (MBSFN) (mbsfn-SubframConfigList), etc. The UE can determine the position of the CRS within the NR time slot corresponding to the LTE subframe based on the above-mentioned information.

[0269] - May include configuration information about resource sets corresponding to one or more zero-power (ZP) CSI-RS within a bandwidth part.

[0270] [About LTE CRS rate matching]

[0271] Next, the rate matching process for the LTE CRS mentioned above will be described in detail. In NR, for coexistence between Long Term Evolution (LTE) and New RAT (NR) (LTE-NR coexistence), the LTE cell-specific reference signal (CRS) pattern can be configured for NR UEs. More specifically, the CRS pattern can be provided through RRC signaling including at least one parameter within the ServingCellConfig IE (information element) or the ServingCellConfigCommon IE. Examples of parameters may include lte-CRS-ToMatchAround, lte-CRS-PatternList1-r16, lte-CRS-PatternList2-r16, crs-RateMatch-PerCORESETPoolIndex-r16, etc.

[0272] Rel-15 NR provides a function by which one CRS pattern can be configured per serving cell via the parameter lte-CRS-ToMatchAround. In Rel-16 NR, the above function has been extended so that multiple CRS patterns can be configured per serving cell. More specifically, a UE with a single TRP (transmit and receive point) configuration can now have one CRS pattern configured per LTE carrier, and a UE with a multi-TRP configuration can now have two CRS patterns configured per LTE carrier. For example, a UE with a single TRP configuration can have up to three CRS patterns configured per serving cell via the parameter lte-CRS-PatternList1-r16. As another example, a UE with a multi-TRP configuration can have a CRS configured for each TRP. That is, the CRS pattern with respect to TRP1 can be configured via the parameter lte-CRS-PatternList1-r16, and the CRS pattern with respect to TRP2 can be configured via the parameter lte-CRS-PatternList2-r16. If two TRPs are configured as described above, whether both the CRS patterns of TRP1 and TRP2 are applied to a specific physical downlink shared channel (PDSCH) or only the CRS pattern of one TRP is applied is determined by the parameter crs-RateMatch-PerCORESETPoolIndex-r16, where if the parameter crs-RateMatch-PerCORESETPoolIndex-r16 is configured to "enabled", only the CRS pattern of one TRP is applied, and in other cases the CRS patterns of two TRPs are applied.

[0273] Table 22 shows ServingCellConfig IE including the CRS pattern, and Table 23 shows RateMatchPatternLTE-CRS IE including at least one parameter regarding the CRS pattern.

[0274] [Table 22]

[0275]

[0276]

[0277]

[0278]

[0279]

[0280]

[0281]

[0282]

[0283]

[0284]

[0285]

[0286] [Table 23]

[0287]

[0288]

[0289]

[0290]

[0291] [PDSCH: Processing Time]

[0292] Next, we will describe the PDSCH processing time (PDSCH processing time). If the base station schedules the UE to transmit the PDSCH using DCI formats 1_0, 1_1, or 1_2, the UE may require PDSCH processing time to receive the PDSCH by applying the transmission method indicated by the DCI (modulation / demodulation and coding indicator index (MCS), demodulation reference signal related information, time and frequency resource allocation information, etc.). Taking this into account, the PUSCH preparation process time is defined in NR. The UE's PUSCH processing time can be based on Equation 2 given below.

[0293] [Equation 2]

[0294] T proc,1 = ( N1 + d 1,1 + d2)( 2048 + 144 ) κ2 -μ T c + T ext

[0295] T described in Equation 3 above proc,1 Each parameter in can have the following meanings.

[0296] N1: The number of symbols determined according to UE processing capability 1 or 2 based on the UE's capabilities and parameter set μ. If UE processing capability 1 is reported according to the UE's capability report, N1 may have the values ​​in Table 24, and if UE processing capability 2 is reported and if the availability of UE processing capability 2 is configured through higher layer signaling, N1 may have the values ​​in Table 25. The parameter set μ may correspond to μ PDCCH 、μ PDSCH 、μ UL The minimum value in order to make T proc,1 maximize, and μ PDCCH 、μ PDSCH 、μ UL It may refer to a parameter set of a PDCCH that schedules a PDSCH, a parameter set of a scheduled PDSCH, and a parameter set of an uplink channel in which HARQ-ACK is to be sent.

[0297] [Table 24] PDSCH processing time when PDSCH processing capability is 1

[0298] [Table 24]

[0299]

[0300] [Table 25] PDSCH processing time for PDSCH processing capability 2

[0301] [Table 25]

[0302]

[0303] -κ: 64

[0304] -T ext : If the UE uses a shared spectrum channel access solution, the UE can calculate T ext And apply it to the PDSCH processing time. Otherwise, T ext is assumed to be 0.

[0305] - If l1 indicating the PDSCH DMRS position value is 12, then N in the above [Table 22] 1,0 has a value of 14 otherwise it has a value of 13.

[0306] - With respect to PDSCH mapping type A, if the last symbol of the PDSCH is the i-th symbol in the slot in which the PDSCH is transmitted, and if i<7, then d 1,1 is 7-i, otherwise d 1,1 It is 0.

[0307] -d2: If the PUCCH with a high priority index overlaps with another PUCCH or a PUCCH with a low priority index in time, d2 of the PUCCH with a high priority index can be configured as a value reported from the UE. Otherwise, d2 is 0.

[0308] - If PDSCH mapping type B is used with respect to UE processing capability 1, then d 1,1 The value may be determined by the number of symbols of the scheduled PDSCH (L) and the number of overlapping symbols between the PDCCH that schedules the PDSCH and the scheduled PDSCH, as described below.

[0309] -If L ≥ 7, then 1,1 =0.

[0310] -If-L≥4 and L≤6, then 1,1 =7-L.

[0311] -If L=3, then d 1,1 =min(d, 1).

[0312] -If L=2, then d 1,1 =3+d.

[0313] - If PDSCH mapping type B is used with respect to UE processing capability 2, then d 1,1 The value may be determined by the number of symbols of the scheduled PDSCH (L) and the number of overlapping symbols between the PDCCH that schedules the PDSCH and the scheduled PDSCH, as described below.

[0314] -If L ≥ 7, then 1,1 =0.

[0315] -If -L≥4 and L≤6, then d 1,1 .

[0316] -If L=2,

[0317] - If the scheduled PDCCH exists within a CORESET consisting of three symbols, and if the CORESET and the scheduled PDSCH have the same starting symbol, then d 1,1 =3.

[0318] - Otherwise, d 1,1 =d.

[0319] - In case that a UE within a given serving cell supports capability 2, if processingType2Enabled (upper layer signaling) is configured as "enabled" with respect to the corresponding cell, a PDSCH processing time based on UE processing capability 2 may be applied by the UE.

[0320] If the position of the first uplink transmission symbol of the PUCCH including the HARQ-ACK information (combined with the corresponding position, K1 defined as the HARQ-ACK transmission time point, the PUCCH resource used to send the HARQ-ACK, and the timing advance effect) is within T proc,1 The UE needs to send a valid HARQ-ACK message starting from the first uplink transmission symbol that comes after the last symbol of PDSCH in time no earlier than the first uplink transmission symbol that comes after the last symbol of PDSCH. That is, the UE needs to send PUCCH containing HARQ-ACK only when there is sufficient time for PDSCH processing. Otherwise, the UE cannot provide the base station with valid HARQ-ACK information corresponding to the scheduled PDSCH. In the case of both normal CP and extended CP, the above T proc,1 In the case of a PDSCH with two PDSCH transmission positions configured within one slot, d is calculated with reference to the first PDSCH transmission position within the corresponding slot. 1,1 .

[0321] [PDSCH: Reception preparation time during cross-carrier scheduling]

[0322] Next, the parameter set (μ) used in sending the scheduling PDCCH will be described. PDCCH ) and the parameter set (μ PDSCH ) In different cross-carrier scheduling situations, the time interval between PDCCH and PDSCH defines the UE’s PDSCH reception repair time (N pdsch ).

[0323] If μ PDCCH <μ PDSCH , then it cannot be in the N starting from the last symbol of the PDCCH that schedules the corresponding PDSCH pdsch The scheduled PDSCH may be sent before the first symbol of the time slot that comes after the first symbol of the time slot that follows the DM-RS. The transmission symbol corresponding to the PDSCH may include a DM-RS.

[0324] If μ PDCCH >μ PDSCH , then the Nth of the last symbol of the PDCCH that schedules the corresponding PDSCH can be pdsch The scheduled PDSCH is sent after 1 symbol. The transmission symbol corresponding to the PDSCH may include DM-RS.

[0325] [Table 26] N according to the scheduled PDCCH subcarrier spacing pdsch

[0326] [Table 26]

[0327]

[0328] [About SRS]

[0329] Next, we will describe an uplink channel estimation method using a UE's Sounding Reference Signal (SRS) transmission. A base station can configure at least one SRS configuration for each uplink BWP to transmit configuration information for SRS transmission to the UE. Furthermore, the base station can configure at least one SRS resource set for each SRS configuration. For example, the base station and the UE can exchange higher-layer signaling information as follows to transmit information regarding the SRS resource set.

[0330] -srs-ResourceSetId: SRS resource set index

[0331] -srs-ResourceIdList: A collection of SRS resource indexes referenced by the SRS resource set

[0332] -resourceType: The time domain transmission configuration of the SRS resource referenced by the SRS resource set, and can be configured as one of "periodic", "semi-persistent", and "aperiodic". If configured as "periodic" or "semi-persistent", associated CSI-RS information can be provided based on the location of the SRS resource set. If configured as "aperiodic", aperiodic SRS resource trigger list / time slot offset information can be provided, and associated CSI-RS information can be provided based on the location of the SRS resource set.

[0333] - Usage: Configuration regarding where the SRS resource referenced by the SRS resource set is used, and can be configured as one of "beamManagement", "Codebook", "Non-Codebook", and "antennaSwitching".

[0334] -alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter configuration for adjusting the transmit power of the SRS resources referenced by the SRS resource set.

[0335] The UE may understand that the SRS resources included in the SRS resource index set referenced by the SRS resource set follow the information configured for the SRS resource set.

[0336] In addition, the base station and the UE may send / receive upper layer signaling information to convey various configuration information about the SRS resources. As an example, the various configuration information about the SRS resources may include time-frequency domain mapping information within the time slot of the SRS resources, and this may include information about frequency hopping within or between time slots of the SRS resources. In addition, the various configuration information about the SRS resources may include the time domain transmission configuration of the SRS resources, and may be configured as one of "periodic", "semi-persistent" and "aperiodic". The time domain transmission configuration of the SRS resources may be restricted to having the same time domain transmission configuration as the SRS resource set that includes the SRS resources. If the time domain transmission configuration of the SRS resources is configured as "periodic" or "semi-persistent", the time domain transmission configuration may further include the SRS resource transmission period and time slot offset (e.g., periodicityAndOffset).

[0337] The base station can activate or deactivate SRS transmission for the UE via higher-layer signaling (e.g., DCI) including RRC signaling, MAC CE signaling, or L1 signaling. For example, the base station can activate or deactivate periodic SRS transmission for the UE via higher-layer signaling. The base station can indicate activation of an SRS resource set whose resourceType is configured as "periodic" via higher-layer signaling, and the UE can transmit SRS resources referenced by the activated SRS resource set. The intra-slot time-frequency domain resource mapping of the transmitted SRS resources complies with the resource mapping information configured for the SRS resources, and the slot mapping, including the transmission period and slot offset, complies with the periodicity and offset configured for the SRS resources. In addition, the spatial domain transmission filter applied to the transmitted SRS resources can refer to the spatial relationship information configured for the SRS resources, or can refer to the associated CSI-RS information configured for the SRS resource set including the SRS resources. The UE can transmit SRS resources within the uplink BWP activated for the periodic SRS resources activated via higher-layer signaling.

[0338] For example, the base station may activate or deactivate semi-persistent SRS transmission for the UE through upper layer signaling. The base station may indicate the activation of the SRS resource set through MAC CE signaling, and the UE may send the SRS resource referenced by the activated SRS resource set. The SRS resource set activated through MAC CE signaling may be limited to the SRS resource set whose resourceType is configured as "semi-persistent". The intra-slot time-frequency domain resource mapping of the transmitted SRS resource follows the resource mapping information configured for the SRS resource, and the slot mapping including the transmission period and slot offset follows the periodicity and offset configured for the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource may refer to the spatial relationship information configured for the SRS resource, or may refer to the associated CSI-RS information configured for the SRS resource set including the SRS resource. If the SRS resource has spatial relationship information configured for it, the spatial domain transmission filter may be determined by referring to the configuration information about the spatial relationship information transmitted through the MAC CE signaling that activates the semi-persistent SRS transmission, without following the spatial relationship information. The UE may transmit SRS resources within the uplink BWP activated with respect to the semi-persistent SRS resources activated by upper layer signaling.

[0339] For example, the base station can trigger the UE's aperiodic SRS transmission through DCI. The base station can indicate one of the aperiodic SRS triggers (aperiodic SRS-ResourceTrigger) through the SRS request field of the DCI. The UE can understand that in the configuration information of the SRS resource set, the SRS resource set triggered by the aperiodic SRS resource indicated by the DCI in the aperiodic SRS resource trigger list has been triggered. The UE can send the SRS resource referenced by the triggered SRS resource set. The time-frequency domain resource mapping within the time slot of the transmitted SRS resource follows the resource mapping information configured for the SRS resource. In addition, the time slot mapping of the transmitted SRS resource can be determined by the time slot offset between the SRS resource and the PDCCH including the DCI, and this can refer to (multiple) values ​​included in the time slot offset set configured for the SRS resource set. Specifically, the time slot offset between the SRS resource and the PDCCH containing the DCI may be the value indicated in the time domain resource allocation field of the DCI, from among the offset values ​​included in the time slot offset set configured for the SRS resource set. Furthermore, the spatial transmission filter applied to the transmitted SRS resource may reference the spatial relationship information configured for the SRS resource, or may reference the associated CSI-RS information configured for the SRS resource set containing the SRS resource. The UE may transmit SRS resources within the uplink BWP associated with the activation of aperiodic SRS resources triggered by DCI. If the base station triggers aperiodic SRS transmission by the UE via DCI, a minimum time interval may be required between the transmitted SRS and the PDCCH containing the DCI triggering the aperiodic SRS transmission, in order for the UE to transmit the SRS by applying the configuration information regarding the SRS resource. The time interval for UE SRS transmission may be defined as the number of symbols between the last symbol of the PDCCH containing the DCI triggering the aperiodic SRS transmission and the first symbol of the first transmitted SRS resource mapped to the transmitted SRS resource(s). The minimum time interval may be determined with reference to the PUSCH preparation process time required for the UE to prepare for PUSCH transmission. Furthermore, the minimum time interval may have different values ​​depending on where the SRS resource set including the transmitted SRS resource is used. For example, the minimum time interval may be determined as N2 symbols, where N2 symbols are defined with reference to the PUSCH preparation process time of the UE, taking into account the UE processing capability according to the UE's capabilities.In addition, if the usage location of the SRS resource set including the transmitted SRS resource is configured as "codebook" or "antenna switching", the minimum time interval may be determined as N2 symbols, and if the usage location of the SRS resource set is set to "non-codebook" or "beam management", the minimum time interval may be determined as N2+14 symbols. If the time interval for aperiodic SRS transmission is greater than or equal to the minimum time interval, the UE may transmit the aperiodic SRS, and if the time interval for aperiodic SRS transmission is less than the minimum time interval, the UE may ignore the DCI triggering the aperiodic SRS.

[0340] [Table 27]

[0341]

[0342]

[0343]

[0344]

[0345]

[0346] The configuration information spatialRelationInfo in Table 27 above may be applied to a beam for SRS transmission corresponding to the beam information of the corresponding reference signal with reference to a reference signal. For example, the configuration of spatialRelationInfo may include the information in Table 28 below.

[0347] [Table 28]

[0348]

[0349] Referring to the spatialRelationInfo configuration, the SS / PBCH block index, CSI-RS index, or SRS index can be configured as the index of the reference signal to be referenced in order to use the beam information of a specific reference signal. The higher-layer signaling referenceSignal corresponds to the configuration information indicating which reference signal beam information will be referenced for the corresponding SRS transmission, ssb-Index refers to the index of the SS / PBCH block, csi-RS-Index refers to the index of the CSI-RS, and srs refers to the index of the SRS. If the upper-layer signaling referenceSignal has a configuration value of "ssb-Index", the UE can apply the receive beam used to receive the SS / PBCH block corresponding to the ssb-Index as the transmit beam for the corresponding SRS transmission. If the upper-layer signaling referenceSignal has a configuration value of "csi-RS-Index", the UE can apply the receive beam used to receive the CSI-RS block corresponding to the csi-RS-Index as the transmit beam for the corresponding SRS transmission. If the upper layer signaling referenceSignal has a configuration value of "srs", the UE can apply the reception beam used to transmit the SRS corresponding to the srs as the transmission beam for the corresponding SRS transmission.

[0350] [PUSCH: About transmission scheme]

[0351] Next, the PUSCH transmission scheduling scheme will be described. PUSCH transmission can be dynamically scheduled by UL grant in DCI, or by configured grant type 1 or type 2. Dynamic scheduling indication for PUSCH transmission can be made via DCI format 0_0 or 0_1.

[0352] Configured grant type 1 PUSCH transmissions may be semi-statically configured by receiving a configuredGrantConfig including the rrc-ConfiguredUplinkGrant in Table 28 via upper layer signaling, without receiving an UL grant in the DCI. Configured grant type 2 PUSCH transmissions may be semi-persistently scheduled by an UL grant in the DCI after receiving a configuredGrantConfig that does not include the rrc-ConfiguredUplinkGrant in Table 28 via upper layer signaling. If the PUSCH transmission is operated by a configured grant, the parameters applied to the PUSCH transmission are applied by configuredGrantConfig (upper layer signaling) in Table 28, except for the scaling of dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and UCI-OnPUSCH provided by pusch-Config (upper layer signaling) in Table 29. If transformPrecoder is provided in configuredGrantConfig (upper layer signaling) in Table 29, the UE applies tp-pi2BPSK in pusch-Config in Table 30 to PUSCH transmissions operated by the configured grant.

[0353] [Table 29]

[0354]

[0355]

[0356]

[0357]

[0358]

[0359]

[0360] 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 within pusch-Config in Table 30, which is upper layer signaling, is "codebook" or "non-codebook", PUSCH transmission can follow the codebook-based transmission method or the non-codebook-based transmission method.

[0361] 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. Upon receiving an indication regarding scheduling of PUSCH transmission through DCI format 0_0, the UE performs beam configuration for PUSCH transmission by using the pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the activated uplink BWP within the serving cell, and PUSCH transmission is based on a single antenna port. Within a BWP for a configured PUCCH resource that does not include pucch-spatialRelationInfo, the UE does not expect scheduling for PUSCH transmission through DCI format 0_0. If the UE does not have a configured txConfig within pusch-Config in Table 30, the UE does not expect scheduling through DCI format 0_1.

[0362] [Table 30]

[0363]

[0364]

[0365]

[0366]

[0367] Next, codebook-based PUSCH transmission will be described. Codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1 and can be operated semi-statically via a configured grant. If codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or semi-statically configured via a configured grant, the UE determines the precoder used for PUSCH transmission based on the SRS Resource Indicator (SRI), the Transmit Precoding Matrix Indicator (TPMI), and the transmission rank (the number of PUSCH transmission layers).

[0368] The SRI can be provided via the SRS resource indicator (a field within the DCI) or configured via srs-ResourceIndicator (higher-layer signaling). During codebook-based PUSCH transmission, a UE can be configured with at least one SRS resource and up to two SRS resources. If the SRI is provided to the UE via DCI, the SRS resource indicated by the corresponding SRI is the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. Furthermore, the TPMI and transmission rank can be provided via the "precoding information and number of layers" field within the DCI or configured via the precodingAndNumberOfLayers field (higher-layer signaling). The TPMI indicates the precoder to be applied to the PUSCH transmission. If a single SRS resource is configured for the UE, the TPMI indicates the precoder to be applied to the configured SRS resource. If multiple SRS resources are configured for the UE, the TPMI indicates the precoder to be applied to the SRS resource indicated by the SRI.

[0369] The precoder to be used for PUSCH transmission is selected from an uplink codebook with the same number of antenna ports as the value of nrofSRS-Ports in SRS-Config (upper signaling). In conjunction with codebook-based PUSCH transmission, the UE determines the codebook subset based on codebookSubset and TPMI in pusch-Config (upper layer signaling). Based on the UE capabilities reported to the base station, codebookSubset in pusch-Config (upper layer signaling) can be configured as one of "fullyAndPartialAndNonCoherent," "partialAndNonCoherent," or "nonCoherent." If the UE reports "partialAndNonCoherent" as a UE capability, the UE does not expect codebookSubset (upper layer signaling) to be configured as "fullyAndPartialAndNonCoherent." Furthermore, if the UE reports "nonCoherent" as a UE capability, the UE does not expect codebookSubset (upper layer signaling) to be configured as "fullyAndPartialAndNonCoherent" or "partialAndNonCoherent." If nrofSRS-Ports within the SRS-ResourceSet (upper layer signaling) indicates two SRS antenna ports, the UE does not expect the value of codebookSubset (upper layer signaling) to be configured as "partialAndNonCoherent".

[0370] The UE may have one SRS resource set configured for it, where the value of usage in SRS-ResourceSet (upper layer signaling) is "codebook", and may indicate one SRS resource by SRI in the corresponding SRS resource set. If multiple SRS resources are configured in an SRS resource set, where the value of usage in SRS-ResourceSet (upper layer signaling) is "codebook", the UE expects the value of nrofSRS-Ports in SRS-Resource (upper layer signaling) to be the same for all SRS resources.

[0371] The UE sends one or more SRS resources included in the SRS resource set whose usage value is configured as "codebook" to the base station according to upper layer signaling, and the base station selects one from the SRS resources sent by the UE and indicates to the UE that it can send PUSCH by using the transmit beam information of the corresponding SRS resource. In conjunction with codebook-based PUSCH transmission, SRI is used as information for selecting an index for an SRS resource and is included in the DCI. In addition, the base station adds information indicating the rank and TPMI to be used by the UE for PUSCH transmission to the DCI. Using the SRS resource indicated by SRI, the UE can apply the precoder indicated by the rank and the TPMI indicated based on the transmit beam of the corresponding SRS resource when performing PUSCH transmission, thereby performing PUSCH transmission.

[0372] Next, we will describe non-codebook-based PUSCH transmissions. Non-codebook-based PUSCH transmissions can be dynamically scheduled using DCI formats 0_0 or 0_1, and can be operated semi-statically using a configured grant. If at least one SRS resource is configured in an SRS resource set where the usage value within the SRS-ResourceSet (upper layer signaling) is "non-codebook," non-codebook-based PUSCH transmissions can be scheduled for the UE using DCI format 0_1.

[0373] Regarding the SRS resource set whose usage value within SRS-ResourceSet (upper layer signaling) is "non-codebook", a connected NZP CSI-RS resource (non-zero power CSI-RS) can be configured for the UE. The UE can calculate the precoder for SRS transmission by measuring the NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the aperiodic SRS transmission in the UE is less than 42 symbols, the UE does not expect the information about the precoder used for SRS transmission to be updated.

[0374] If the configured value of resourceType within the SRS-ResourceSet (upper layer signaling) is "aperiodic," the attached NZP CSI-RS is indicated by the SRS request, which is a field within DCI format 0_1 ​​or 1_1. If the attached NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, a value other than "00" for the SRS request (a field within DCI format 0_1 ​​or 1_1) indicates the presence of the attached NZP CSI-RS. The corresponding DCI should not indicate cross-carrier or cross-BWP scheduling. Furthermore, if the SRS request value 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.

[0375] If a periodic or semi-persistent SRS resource set is configured, the connected NZP CSI-RS can be indicated by the associatedCSI-RS in the SRS-ResourceSet (higher layer signaling).For non-codebook based transmission, the UE does not expect the upper layer signaling spatialRelationInfo related to the SRS resource to be configured together with the associated CSI-RS in the SRS-ResourceSet (higher layer signaling).

[0376] If multiple SRS resources are configured for a UE, the UE can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. The SRI can be indicated by the SRS resource indicator (a field within the DCI) or configured via the srs-ResourceIndicator (higher layer signaling). Similar to the codebook-based PUSCH transmission described above, if the SRI is provided to the UE via DCI, the SRS resource indicated by the corresponding SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH including the corresponding 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 within 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 is configured with one SRS port for each SRS resource. There can be only one configured SRS resource set where the value of usage within SRS-ResourceSet (upper layer signaling) is "non-codebook", and a maximum of four SRS resources can be configured for non-codebook based PUSCH transmission.

[0377] The base station sends an NZP-CSI-RS connected to an SRS resource set to the UE, and the UE calculates the precoder used when sending one or more SRS resources in the corresponding SRS resource set based on the measurement result when the corresponding NZP-CSI-RS is received. When sending one or more SRS resources in the SRS resource set to the base station, the UE applies the calculated precoder, where the configured usage is "non-codebook", 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 can indicate an index of an 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 sent by the base station can 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.

[0378] [PUSCH: Preparation process time]

[0379] Next, we'll describe the PUSCH preparation process time. If a base station schedules a UE to transmit a PUSCH using DCI formats 0_0, 0_1, or 0_2, the UE may require the PUSCH preparation process time to transmit the PUSCH using the transmission method indicated by the DCI (SRS resource transmission precoding method, number of transmission layers, spatial domain transmission filter). With this in mind, the PUSCH preparation process time is defined in NR. The UE's PUSCH preparation process time can be determined according to Equation 3 below.

[0380] [Equation 3]

[0381] T proc,2 = max(( N2+ d 2,1 + d2)( 2048 + 144 ) κ2 -μ T c + T ext + T switch , d 2,2 )

[0382] T described in Equation 3 above proc,2 Each parameter in can have the following meanings.

[0383] N2: The number of symbols determined according to UE processing capability 1 or 2 based on the UE's capabilities and parameter set μ. If UE processing capability 1 is reported according to the UE's capability report, N2 may have the value in Table 30, and if UE processing capability 2 is reported and if the availability of UE processing capability 2 is configured through higher layer signaling, N2 may have the value in Table 31.

[0384] [Table 31]

[0385]

[0386] [Table 32]

[0387]

[0388] -d 2,1 : If all resource elements of the first OFDM symbol of PUSCH transmission include DM-RS, the number of symbols is determined to be 0, otherwise it is 1.

[0389] -κ: 64

[0390] -μ: follow and The value in , which makes T proc,2 Bigger. refers to a downlink parameter set for transmitting a PDCCH including DCI scheduling a PUSCH, and Refers to the uplink parameter set used to send PUSCH.

[0391] -T c :have

[0392] -d 2,2 : If the DCI scheduling PUSCH indicates BWP switching, follow the BWP switching time, and otherwise 0.

[0393] -d2: If OFDM symbols overlap in time between a PUSCH with a high priority index and a PUCCH with a low priority index, the d2 value of the PUSCH with the high priority index is used. Otherwise, d2 is 0.

[0394] -T ext : If the UE uses a shared spectrum channel access solution, the UE can calculate T ext And apply it to the PDSCH preparation process time. Otherwise, T ext is assumed to be 0.

[0395] -T switch : If the uplink switching interval has been triggered, then T switch is assumed to be the switching interval. Otherwise, T switch is assumed to be 0.

[0396] Taking into account the influence of the timing advance between uplink and downlink and the time domain resource mapping information of the PUSCH scheduled by the DCI, if the first symbol of the PUSCH starts earlier than the first uplink symbol of the CP starting after the last symbol Tproc,2 of the PDCCH including the DCI scheduling the PUSCH, the base station and the UE determine that the PUSCH preparation process time is insufficient. Otherwise, the base station and the UE determine that the PUSCH preparation process time is sufficient. The UE can send the PUSCH only when the PUSCH preparation process time is sufficient, and can ignore the DCI scheduling the PUSCH when the PUSCH preparation process time is insufficient.

[0397] [PUSCH: About repeated transmission]

[0398] The following describes the repeated transmission of uplink data channels in 5G systems in detail. 5G systems support two types of uplink data channel repeated transmission methods: PUSCH repetition type A transmission and PUSCH repetition type B transmission. A UE can be configured to use either PUSCH repetition type A or PUSCH repetition type B transmission via upper layer signaling.

[0399] PUSCH repetition type A transmission

[0400] -As described above, the symbol length and the position of the start symbol of the uplink data channel can be determined in one time slot by the time domain resource allocation method, and the base station can notify the UE of the number of repeated transmissions through upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0401] -Based on the number of repeated transmissions received from the base station, the UE may repeatedly transmit an uplink data channel having the same length and starting symbol as the configured uplink data channel in consecutive time slots. If the base station configures the time slot as a downlink for the UE, or if at least one of the symbols of the uplink data channel configured for the UE is configured as a downlink, the UE omits the uplink data channel transmission but counts the number of repeated transmissions of the uplink data channel.

[0402] PUSCH repetition type B transmission

[0403] As described above, the symbol length and the position of the starting symbol of the uplink data channel can be determined in one time slot by a time domain resource allocation method, and the base station can notify the UE of the number of repetitions through upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0404] Based on the previously configured starting symbol and length of the uplink data channel, the nominal repetition of the uplink data channel is determined as follows. The time slot where the nth nominal repetition starts is given by is given by , and the time slot in which the symbol starts is given by The time slot at the end of the nth nominal repetition is given by is given by , and the time slot in which the symbol ends is given by Here, n=0, ..., numberofrepetitions-1, S refers to the starting symbol of the configured uplink data channel, and L refers to the symbol length of the configured uplink data channel. is the time slot where PUSCH transmission starts, and Refers to the number of symbols per time slot.

[0405] -The UE determines invalid symbols for PUSCH repetition type B transmission. Symbols configured as downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated are determined to be invalid symbols for PUSCH repetition type B transmission. In addition, invalid symbols can be configured in upper-layer parameters (e.g., InvalidSymbolPattern). The upper-layer parameters (e.g., InvalidSymbolPattern) can provide a symbol-level bitmap across one or two time slots to configure invalid symbols. In the bitmap, a 1 indicates an invalid symbol. In addition, the periodicity and pattern of the bitmap can be configured by the upper-layer parameters (e.g., InvalidSymbolPattern). If a higher layer parameter (e.g., InvalidSymbolPattern) is configured, and if the parameter InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 indicates 1, the UE applies the invalid symbol pattern, and if the above parameter indicates 0, the UE does not apply the invalid symbol pattern. If a higher layer parameter (e.g., InvalidSymbolPattern) is configured, and if the parameter InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 is not configured, the UE applies the invalid symbol pattern.

[0406] After determining the invalid symbols, the UE may consider symbols other than the invalid symbols as valid symbols for each nominal repetition. If each nominal repetition includes one or more valid symbols, the nominal repetition may include one or more actual repetitions. Each actual repetition includes a set of consecutive valid symbols that can be used for PUSCH repetition transmission type B in a time slot.

[0407] Figure 14 An example of PUSCH repetition type B transmission in a wireless communication system according to an embodiment of the present disclosure is shown. The UE may receive the following configuration: the start symbol S of the uplink data channel is 0, the length L of the uplink data channel is 14, and the number of repeated transmissions is 16. In this case, the nominal repetition may appear in 16 consecutive time slots (1405). Thereafter, the UE may determine that the symbols configured as downlink symbols in each nominal repetition 1405 are invalid symbols. The UE determines that the symbols configured as 1 in the invalid symbol pattern 1410 are invalid symbols. If valid symbols other than the invalid symbols in the corresponding nominal repetition constitute one or more consecutive symbols in one time slot, they are configured as actual repetitions and transmitted (1415).

[0408] In addition, regarding PUSCH repetition transmission, additional methods for UL grant-based PUSCH transmission across slot boundaries and configured grant-based PUSCH transmission may be defined in NR Release 16 as follows:

[0409] Method 1 (mini-slot repetition): Two or more PUSCH repetitions are scheduled within a slot or across the boundaries of consecutive slots using a single UL grant. In conjunction with Method 1, the time-domain resource allocation information within the DCI indicates the resources for the first repetition. Furthermore, the time-domain resource information for the remaining repetitions is determined based on the time-domain resource information for the first repetition and the uplink or downlink direction determined for each symbol in each slot. Each repetition occupies consecutive symbols.

[0410] - Method 2 (Multi-segment Transmission): Two or more PUSCH repetition transmissions are scheduled in consecutive time slots using one UL grant. Transmission number 1 is assigned to each time slot, and the starting point or repetition length varies between transmissions. In Method 2, the time domain resource allocation information within the DCI indicates the starting point and repetition length of all repetition transmissions. When repetition transmission is performed within a single time slot using Method 2, if multiple consecutive uplink symbol bundles exist in the corresponding time slot, corresponding repetition transmissions can be performed for the corresponding uplink symbol bundle. If a single consecutive uplink symbol bundle exists in the corresponding time slot, one PUSCH repetition transmission is performed according to the NR Release 15 method.

[0411] -Method 3: Two or more PUSCH repetition transmissions are scheduled in consecutive time slots by two or more UL grants. Transmission number 1 may be designated for each time slot, and the nth UL grant may be received before the PUSCH transmission scheduled by the (n-1)th UL grant ends.

[0412] -Method 4: One or more PUSCH repetition transmissions within a single time slot, or two or more PUSCH repetition transmissions across consecutive time slot boundaries, can be supported by one UL grant or one configured grant. The number of repetitions indicated by the base station to the UE is only a nominal value, and the UE may actually perform more PUSCH repetition transmissions than the nominal number of repetitions. The time domain resource allocation information within the DCI or configured grant refers to the resources of the first repetition transmission indicated by the base station. The time domain resource information of the remaining repetition transmissions can be determined with reference to the resource information of the first repetition transmission and the uplink or downlink direction of the symbol. If the time domain resource information of the repetition transmission indicated by the base station crosses the time slot boundary or includes an uplink / downlink switching point, the corresponding repetition transmission can be divided into multiple repetition transmissions. With respect to each uplink cycle, one repetition transmission can be included in one time slot.

[0413] [PUSCH: Frequency Hopping Process]

[0414] Hereinafter, frequency hopping of a physical uplink shared channel (PUSCH) in a 5G system will be described in detail.

[0415] For each PUSCH repetition transmission type, 5G supports two PUSCH frequency hopping methods. First, in PUSCH repetition transmission type A, both intra-slot and inter-slot hopping are supported, and in PUSCH repetition transmission type B, both inter-repetition and inter-slot hopping are supported.

[0416] Intra-slot frequency hopping methods supported in PUSCH repetition type A transmissions may include a method in which the UE transmits allocated resources in the frequency domain over two hops within one slot after changing the allocated resources to a configured frequency offset. The starting RB for each hop associated with intra-slot frequency hopping may be represented by Equation 4 below.

[0417] [Equation 4]

[0418]

[0419] In Equation 4, i=0 and i=1 can represent the first hop and the second hop respectively, and RB start It can indicate the starting RB in the UL BWP and can be calculated from the frequency resource allocation method. offset represents the frequency offset between two hops via higher layer parameters. The number of symbols in the first hop can be determined by , and the number of symbols in the second hop can be represented by express. is the length of a PUSCH transmission in one slot and is represented by the number of OFDM symbols.

[0420] Next, the inter-slot frequency hopping method supported in PUSCH repetition type A and type B transmission is a method in which the UE transmits the resource in each slot after changing the resource allocated in the frequency domain by the configured frequency offset. The start RB of the period can be expressed by the following Equation 5.

[0421] [Equation 5]

[0422]

[0423] In Equation 5, Indicates the current slot number during multi-slot PUSCH transmission, and RB start Indicates the starting RB within the UL BWP and is calculated from the frequency resource allocation method. offset Indicates the frequency offset between two hops via higher-layer parameters.

[0424] Next, the inter-repetition frequency hopping method supported in PUSCH repetition type B transmission is a method in which the resources allocated in the frequency domain for one or more actual repetitions in each nominal repetition are shifted by the configured frequency offset and then transmitted. Index RB of the starting RB in the frequency domain for one or more actual repetitions in the nth nominal repetition start(n) It can be followed from Equation 6 given below.

[0425] [Equation 6]

[0426]

[0427] In Equation 6, n represents the index of the nominal repetition, and RB offset Indicates the RB offset between two hops using higher-layer parameters.

[0428] [PUSCH: Multiplexing rules during AP / SP CSI reporting]

[0429] The following describes in detail the method for measuring and reporting channel status in a 5G communication system. Channel state information (CSI) may include a channel quality indicator (CQI), a precoding matrix index (PMI), a CSI-RS resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), and reference signal received power (L1-RSRP). The base station may control the time and frequency resources used for the UE's CSI measurement and reporting.

[0430] For the above CSI measurement and reporting, the UE can configure the configuration information of N (N ≥ 1) CSI reports (CSI-ReportConfig), the configuration information of M (M ≥ 1) RS transmission resources (CSI-ResourceConfig), and one or two trigger state lists (CSI-AperiodicTriggerStateList, CSI-SemiPersistentOnPUSCH-TriggerStateList) via higher layer signaling. More specifically, the configuration information for the above CSI measurement and reporting can be as described in the following [Table 33] to [Table 39].

[0431] [Table 33] CSI-ReportConfig

[0432] The IE CSI-ReportConfig is used to configure periodic or semi-persistent reporting sent on the PUCCH on the cell that includes the CSI-ReportConfig, or to configure semi-persistent or aperiodic reporting sent on the PUSCH triggered by DCI received on the cell that includes the CSI-ReportConfig (in this case, the cell sending the report is determined by the received DCI). See TS 38.214

[19] , clause 5.2.1.

[0433] CSI-ReportConfig Information Element

[0434] [Table 33]

[0435]

[0436]

[0437]

[0438]

[0439]

[0440]

[0441]

[0442]

[0443]

[0444]

[0445]

[0446]

[0447]

[0448]

[0449]

[0450]

[0451]

[0452]

[0453]

[0454]

[0455]

[0456]

[0457] [Table 34] CSI-ReportConfig. IE CSI-ResourceConfig defines a group of one or more NZP-CSI-RS-ResourceSet, CSI-IM-ResourceSet and / or CSI-SSB-ResourceSet.

[0458] CSI-ResourceConfig information element

[0459] [Table 34]

[0460]

[0461]

[0462]

[0463]

[0464] Table 35: NZP-CSI-RS-ResourceSet

[0465] The IE NZP-CSI-RS-ResourceSet is the set of non-zero power (NZP) CSI-RS resources (their IDs) and set-specific parameters.

[0466] NZP-CSI-RS-ResourceSet information element

[0467] [Table 35]

[0468]

[0469]

[0470]

[0471]

[0472] Table 36: CSI-SSB-ResourceSet

[0473] The IE CSI-SSB-ResourceSet is used to configure an SS / PBCH block resource set, which references the SS / PBCH as indicated in ServingCellConfigCommon.

[0474] CSI-SSB-ResourceSet information element

[0475] [Table 36]

[0476]

[0477] Table 37: CSI-IM-ResourceSet

[0478] The IE CSI-IM-ResourceSet is used to configure a set of one or more CSI Interference Management (IM) resources (their IDs) and set-specific parameters.

[0479] CSI-IM-ResourceSet information element

[0480] [Table 37]

[0481]

[0482] [Table 38]CSI-AperiodicTrrigerStateList

[0483] The CSI-AperiodicTriggerStateList IE is used to configure a list of aperiodic trigger states for the UE. Each code point of the DCI field "CSI request" is associated with a trigger state. Upon receiving a value associated with a trigger state, the UE will perform CSI-RS (reference signal) measurement and aperiodic reporting on L1 according to all entries in the associatedReportConfigInfoList for that trigger state.

[0484] CSI-AperiodicTriggerStateList information element

[0485] [Table 38]

[0486]

[0487]

[0488]

[0489]

[0490]

[0491]

[0492] [Table 39]CSI-SemiPersistentOnPUSCH-TriggerStateList

[0493] The CSI-SemiPersistentOnPUSCH-TriggerStateList IE is used to configure the trigger state list for the UE to semi-persistently report channel state information on L1. See also TS 38.214

[19] , clause 5.2.

[0494] CSI-SemiPersistentOnPUSCH-TriggerStateList information element

[0495] [Table 39]

[0496]

[0497] Regarding the aforementioned CSI reporting configuration (CSI-ReportConfig), each reporting configuration (CSI-ReportConfig) can be associated with a downlink (DL) bandwidth part, identified by the higher-layer parameter bandwidth part identifier (bwp-id) given by the CSI resource configuration (CSI-ResourceConfig) associated with the corresponding reporting configuration. For each reporting configuration (CSI-ReportConfig), time-domain reporting can support "aperiodic," "semi-persistent," and "periodic" schemes, which can be configured by the base station for the UE via the reportConfigType parameter configured from higher layers. Semi-persistent CSI reporting methods can support the "semi-persistent on PUCCH" method and the "semi-persistent on PUSCH" method. In the case of periodic or semi-persistent CSI reporting methods, the base station can configure the PUCCH or PUSCH resources on which the CSI is transmitted for the UE via higher-layer signaling. The periodicity and slot offset of the PUCCH or PUSCH resources in which the CSI is to be transmitted can be given by the parameter set of the uplink (UL) bandwidth portion configured for CSI report transmission. In the case of aperiodic CSI reporting, the base station can schedule the PUSCH resources in which the CSI is to be transmitted to the UE via L1 signaling (the aforementioned DCI format 0_1).

[0498] Regarding the above-mentioned CSI resource configuration (CSI-ResourceConfig), each CSI resource configuration CSI-ReportConfig may include S (≥1) CSI resource sets (e.g., given via the higher-layer parameter csi-RS-ResourceSetList). The CSI resource set list may include non-zero power (NZP) CSI-RS resource sets and SS / PBCH block sets, or may include CSI interference measurement (CSI-IM) resource sets. Each CSI resource configuration may be located in a downlink (DL) bandwidth part identified by the higher-layer parameter bwp-id and may be connected to a CSI report configuration in the same downlink bandwidth part. The time domain operation of the CSI-RS resources in the CSI resource configuration may be configured as one of "aperiodic," "periodic," or "semi-persistent" from the higher-layer parameter resourceType. For periodic or semi-persistent CSI resource configurations, the number of CSI-RS resource sets may be limited to S (S=1), and the configured periodicity and slot offset may be given based on the parameter set for the downlink bandwidth part identified by bwp-id. One or more CSI resource settings for channel or interference measurement may be configured by the base station for the UE via higher layer signaling, and may include, for example, the following CSI resources.

[0499] -CSI-IM resources for interference measurement

[0500] -NZP CSI-RS resources used for interference measurement

[0501] -NZP CSI-RS resources for channel measurement

[0502] Regarding a CSI-RS resource set associated with a resource setting in which the higher-layer parameter of resourceType is configured as "aperiodic", "periodic", or "semi-persistent", the trigger state of the CSI report setting with reportType configured as "aperiodic" and the resource setting for channel or interference measurement on one or more component cells (CCs) can be configured via the higher-layer parameter of CSI-AperiodicTriggerStateList.

[0503] The UE's aperiodic CSI reporting can be performed using the PUSCH, periodic CSI reporting can be performed using the PUCCH, and semi-persistent CSI reporting can be performed using the PUSCH when triggered or activated via the DCI, and after being activated via the MAC Control Element (MAC CE), using the PUCCH. As described above, the CSI resource setting can also be configured as aperiodic, periodic, or semi-persistent. Based on the following Table 40, a combination of CSI report settings and CSI resource settings can be supported.

[0504] [Table 40]

[0505] Table 5.2.1.4-1: Triggering / activating CSI reporting for possible CSI-RS configurations

[0506] [Table 40]

[0507]

[0508]

[0509] Aperiodic CSI reporting can be triggered by the "CSI request" field in DCI format 0_1 ​​as described above, which corresponds to scheduling DCI for PUSCH. The UE can monitor the PDCCH, obtain DCI format 0_1, and obtain scheduling information and a CSI request indicator for the PUSCH. The CSI request indicator can be configured with NTS (= 0, 1, 2, 3, 4, 5, or 6) bits and can be determined by higher-layer signaling (reportTriggerSize). One of one or more aperiodic CSI report trigger states (CSI-AperiodicTriggerStateList) that can be configured via higher-layer signaling can be triggered by the CSI request indicator.

[0510] If all bits in the CSI request field are 0, this may indicate that no CSI report is requested.

[0511] If the number M of CSI trigger states configured in CSI-AperiodicTriggerStateLite is greater than 2NT-1, the M CSI trigger states can be mapped to 2NT-1 trigger states according to a predefined mapping relationship, and one of the 2NT-1 trigger states can be indicated by the CSI request field.

[0512] If the number M of CSI triggering states configured in CSI-AperiodicTriggerStateLite is less than or equal to 2NT-1, one of the M CSI triggering states may be indicated by the CSI request field.

[0513] Table 41 below shows an example of the relationship between the CSI request indicator and the CSI triggering state, which can be indicated by the corresponding indicator.

[0514] [Table 41]

[0515]

[0516] The UE can measure CSI resources in a CSI triggering state triggered by the CSI request field and then generate CSI (e.g., including at least one of the aforementioned CQI, PMI, CRI, SSBRI, LI, RI, or L1-RSRP) based on the measurement. The UE can transmit the acquired CSI using the PUSCH scheduled via the corresponding DCI format 0_1. If one bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 ​​indicates "1," the UE can multiplex uplink data (UL-SCH) and the acquired CSI on the PUSCH resources scheduled by DCI format 0_1 ​​for transmission. If one bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 ​​indicates "0," the UE can map only the CSI, without the uplink data (UL-SCH), to the PUSCH resources scheduled by DCI format 0_1 ​​for transmission. Figure 13 An example of an aperiodic CSI reporting method according to an embodiment of the present disclosure is shown.

[0517] exist Figure 13 In example 1300, a UE can obtain DCI format 0_1 ​​by monitoring PDCCH 1301 and obtain scheduling information and CSI request information for PUSCH 1305 from it. The UE can obtain resource information for CSI-RS 1302 to be measured from the received CSI request indicator. The UE can determine the time point at which the UE needs to measure the resources of CSI-RS 1302 based on the time point at which DCI format 0_1 ​​is received and the offset parameter (e.g., the aforementioned aperiodicTriggeringOffset) used in the CSI resource set configuration (e.g., the NZP CSI-RS resource set configuration (NZP-CSI-RS-ResourceSet)). More specifically, the UE can be configured with an offset value X for the parameter aperiodicTriggeringOffset in the NZP-CSI-RS resource set configuration from the base station via higher layer signaling. The configured offset value X can refer to the offset between the time slot in which the DCI triggering the aperiodic CSI report is received and the time slot in which the CSI-RS resources are transmitted. For example, the aperiodicTriggeringOffset parameter value and the offset value X may have a mapping relationship as shown in Table 42 below.

[0518] [Table 42]

[0519]

[0520] Figure 13Example 1300 shows an example in which the aforementioned offset value X is configured as 0 (X=0). In this case, the UE may receive the time slot of the DCI format 0_1 ​​that triggers the aperiodic CSI report (corresponding to Figure 13 The UE receives CSI-RS 1302 in time slot 0 1306 of the received CSI-RS and can report CSI information measured based on the received CSI-RS to the base station via PUSCH 1305. The UE can obtain scheduling information on PUSCH 1305 for CSI reporting (information corresponding to each field of the above-mentioned DCI format 0_1) from DCI format 0_1. For example, in DCI format 0_1, the UE can obtain information about the time slot in which PUSCH 1305 is to be transmitted from the time domain resource allocation information of the above-mentioned PUSCH 1305. Figure 13 In the example 1300, the UE obtains 3 as the K2 value corresponding to the PDCCH to PUSCH slot offset value, and therefore, the PUSCH 1305 can be transmitted in slot 3 1309 which is spaced 3 slots apart from slot 0 1306 (ie, the time point at which the PDCCH 1301 has been received). Figure 13 In example 1310, the UE can obtain DCI format 0_1 ​​by monitoring PDCCH 1311, and can obtain scheduling information and CSI request information of PUSCH 1315 from it. The UE can obtain resource information of CSI-RS 1312 to be measured from the received CSI request indicator. Figure 13 Example 1310 shows an example in which the above-mentioned CSI-RS offset value X is configured as 1 (X=1). In this case, the UE can receive the time slot of the DCI format 0_1 ​​that triggers the aperiodic CSI report (corresponding to Figure 13 The CSI-RS 1312 is received in time slot 01316), and CSI information measured based on the received CSI-RS can be reported to the base station via the PUSCH 1315.

[0521] The aperiodic CSI report may include at least one or both of CSI Part 1 and CSI Part 2, and when the aperiodic CSI report is transmitted via the PUSCH, the aperiodic CSI report may be multiplexed on a transport block. After the CRC is inserted into the input bits for the multiplexed aperiodic CSI, coding and rate matching may be performed, and then transmission may be performed by mapping to resource elements within the PUSCH in a specific pattern. Depending on the coding method or the length of the input bits, CRC insertion may be omitted. The number of modulation symbols calculated for rate matching during multiplexing of CSI Part 1 or CSI Part 2 included in the aperiodic CSI report may be calculated as shown in Table 43 below.

[0522] [Table 43]

[0523]

[0524]

[0525]

[0526]

[0527] Specifically, for repeated PUSCH transmission schemes A and B, the UE may multiplex the aperiodic CSI report only on the first repetition in the PUSCH repetition transmission in order to send the aperiodic CSI report. This is because the aperiodic CSI report information to be multiplexed is encoded in a polar code manner, and at this time, each PUSCH repetition needs to have the same frequency and time resource allocation in order to multiplex the aperiodic CSI report information on multiple PUSCH repetitions. In particular, in the case of PUSCH repetition type B transmission, since each actual repetition can have a different OFDM symbol duration, the aperiodic CSI report can be multiplexed only on the first repetition and then sent. In addition, for repeated PUSCH transmission scheme B, when the UE receives a DCI for activating semi-persistent CSI reporting or scheduling aperiodic CSI reporting without scheduling a transport block, the UE may assume that the value of the nominal repetition is 1 even if the number of repeated PUSCH transmissions configured via higher layer signaling is greater than 1. In addition, when aperiodic or semi-persistent CSI reporting is scheduled or activated without scheduling a transport block based on repeated PUSCH transmission scheme B, the UE may expect the first nominal repetition to be the same as the first actual repetition. With respect to PUSCH transmitted while including semi-persistent CSI, based on repeated PUSCH transmission scheme B, if no DCI is scheduled after semi-persistent CSI reporting has been activated via DCI, if the first nominal repetition is different from the first actual repetition, the transmission for the first nominal repetition may be ignored.

[0528] [About UE Capability Report]

[0529] In LTE and NR, a UE can perform a process of reporting the capabilities supported by the UE to the corresponding base station while connected to the serving base station. In the following description, the above process will be referred to as UE capability reporting.

[0530] A base station can send a UE Capability Query message to a connected UE to request a capability report. This message may include a UE capability request for each radio access technology (RAT) type associated with the base station. RAT-type-specific requests may include information such as supported frequency band combinations. Furthermore, in the case of a UE Capability Query message, a single RRC message container sent by the base station can be used to request UE capabilities for multiple RAT types, or the base station can transmit a UE Capability Query message that includes multiple UE capability requests for corresponding RAT types. In other words, the capability query can be repeated multiple times in a single message, and the UE can configure and report corresponding UE capability information messages multiple times. In next-generation mobile communication systems, UE capability requests for Multi-RAT Dual Connectivity (MR-DC), such as NR, LTE, and E-UTRA-NR Dual Connectivity (EN-DC), can be made. Typically, the UE Capability Query message is initially sent after the UE connects to the base station, but the base station can request the UE Capability Query message under any conditions if desired.

[0531] In the above steps, upon receiving the UE capability report request from the base station, the UE configures the UE capabilities based on the frequency band information and RAT type requested by the base station. The following summarizes the method for configuring UE capabilities in the NR system.

[0532] 1. If the UE receives a list of LTE and / or NR frequency bands from the base station in response to a UE capability request, the UE constructs a frequency band combination (BC) for EN-DC and NR standalone (SA). That is, the UE configures a candidate list of BCs for EN-DC and NR SA based on the frequency bands received from the base station in response to a request via FreqBandList. The frequency bands are prioritized in the order described in FreqBandList.

[0533] 2. If the base station sets the "eutra-nr-only" flag or the "eutra" flag and requests UE capability reporting, the UE removes all content related to NR SA BC from the configured BC candidate list. Such an operation can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0534] 3. The UE then removes the fallback BC from the candidate BC list configured in the above steps. As used herein, a fallback BC refers to a BC that can be obtained by removing the frequency band corresponding to at least one SCell from a specific BC. Since the BC before removing the frequency band corresponding to at least one SCell may already cover the fallback BC, the fallback BC can be omitted. This step also applies to MR-DC, that is, to LTE bands. The BCs remaining after the above steps constitute the final "candidate BC list."

[0535] 4. The UE selects a BC suitable for the requested RAT type from the final "candidate BC list" and configures the BC to be reported. In this step, the UE configures the supportedBandCombinationList in a determined order. That is, the UE configures the BC and UE capabilities for reporting according to the pre-configured rat-Type order (nr->eutra-nr->eutra). In addition, the UE configures the featureSetCombination for the configured supportedBandCombinationList and configures a list of "candidate feature set combinations" from the candidate BC list, from which the list of fallback BCs (including capabilities of the same or lower order) is deleted. The "candidate feature set combinations" can include all feature set combinations for NR and EUTRA-NR BCs and can be obtained from the feature set combinations of the containers of UE-NR-Capabilities and UE-MRDC-Capabilities.

[0536] 5. If the requested RAT type is eutra-nr and has an impact, featureSetCombinations is included in the container of UE-MRDC-Capabilities and UE-NR-Capabilities. However, the feature set of NR is only included in UE-NR-Capabilities.

[0537] After configuring the UE capabilities, the UE transmits a UE capability information message including the UE capabilities to the base station. The base station performs scheduling and transmission / reception management suitable for the UE based on the UE capabilities received from the UE.

[0538] [About CA / DC]

[0539] Figure 10 The radio protocol structures of a base station and a UE in the case where a wireless communication system focuses on a single cell, carrier aggregation, and dual connectivity according to an embodiment of the present disclosure are shown.

[0540] refer to Figure 15 The radio protocols of the mobile communication system include NR Service Data Adaptation Protocol (SDAP) S25 or S70, NR Packet Data Convergence Protocol (PDCP) S30 or S65, NR Radio Link Control (RLC) S35 or S60, and NR Medium Access Control (MAC) S40 or S55 on each of the UE side and the NR base station side.

[0541] The main functions of NR SDAP S25 or S70 may include some of the following functions.

[0542] -Transmission of user plane data

[0543] -Mapping between QoS flows and DRBs for both DL and UL

[0544] - Marking QoS Flow ID in both DL and UL packets

[0545] -Reflective QoS flow to DRB mapping for UL SDAP PDU

[0546] Regarding SDAP layer devices, the UE can configure whether to use the header of the SDAP layer device or whether to use the function of the SDAP layer device for each PDCP layer device or each bearer or each logical channel through an RRC message, and if the SDAP header is configured, the non-access layer (NAS) QoS reflection configuration 1-bit indicator (NAS reflection QoS) and AS QoS reflection configuration 1-bit indicator (AS reflection QoS) of the SDAP header can be indicated, so that the UE can update or reconfigure the mapping information of the QoS flow and data bearer for the uplink and downlink. The SDAP header may include QoS flow ID information indicating QoS. The QoS information can be used as data processing priority, scheduling information, etc. for smoothly supporting services.

[0547] The main functions of NR PDCP S30 or S65 may include some of the following functions.

[0548] -Header compression and decompression: ROHC only

[0549] -Transmission of user data

[0550] - Sequential delivery of upper layer PDUs

[0551] - Out-of-order delivery of upper layer PDUs

[0552] -PDCP PDU reordering for reception

[0553] -Duplicate detection of lower layer SDUs

[0554] -Retransmission of PDCP SDU

[0555] -Encryption and decryption

[0556] - Timer-based SDU discard in uplink

[0557] The reordering of the NR PDCP device mentioned above refers to the function of reordering the PDCP PDUs received from the lower layer in the order based on the PDCP sequence number (SN), and may include the function of delivering the data to the upper layer in the reordered sequence. Alternatively, the reordering of the NR PDCP device may include the function of immediately delivering the data without considering the order, the function of recording the PDCP PDUs lost due to reordering, the function of reporting the status of the lost PDCP PDUs to the transmitting side, and the function of requesting the retransmission of the lost PDCP PDUs.

[0558] The main functions of NR RLC S35 or S60 may include some of the following functions.

[0559] -Transmission of upper layer PDU

[0560] - Sequential delivery of upper layer PDUs

[0561] - Out-of-order delivery of upper layer PDUs

[0562] - Error correction through ARQ

[0563] - Concatenation, segmentation and reassembly of RLC SDUs

[0564] - Re-segmentation of RLC data PDUs

[0565] -Reordering of RLC data PDUs

[0566] -Duplicate detection

[0567] -Protocol error detection

[0568] -RLC SDU discarded

[0569] -RLC reconstruction

[0570] The in-sequence delivery of the NR RLC device mentioned above refers to a function of delivering the RLC SDUs received from the lower layer to the upper layer in sequence. The in-sequence delivery of the NR RLC device may include a function of reassembling and delivering a plurality of RLC SDUs into which one original received RLC SDU has been segmented, may include a function of reordering the received RLC PDUs with reference to the RLC sequence number (SN) or the PDCP sequence number (SN), may include a function of recording the RLC PDUs lost due to reordering, may include a function of reporting the status of the lost RLC PDUs to the transmitting side, and may include a function of requesting the retransmission of the lost RLC PDUs. The in-sequence delivery of the NR RLC device may include a function of continuously delivering to the upper layer only the RLC SDUs preceding the lost RLC SDU if there is a lost RLC SDU, and may include a function of continuously delivering to the upper layer all RLC SDUs received before the start of the timer if a predetermined timer has expired although there is a lost RLC SDU. Alternatively, the in-sequence delivery of the NR RLC device may include the following function: if a predetermined timer has expired, all RLC SDUs received so far are continuously delivered to the upper layer despite the existence of lost RLC SDUs. In addition, the in-sequence delivery of the NR RLC device may include the function of processing RLC PDUs in the order of reception (regardless of the sequence number order, in the order of arrival) and delivering them to the PDCP device regardless of the order (out-of-order delivery), and may also include the function of receiving segments stored in a buffer or to be received later, reconfiguring them into a complete RLC PDU, processing them, and delivering them to the PDCP device in the case of segmentation. The NR RLC layer may not include a concatenation function, which may be performed in the NR MAC layer or replaced by a multiplexing function of the NR MAC layer.

[0571] Out-of-order delivery of the NR RLC device refers to the function of immediately delivering the RLC SDU received from the lower layer to the upper layer without considering the order, which may include reassembling and delivering the multiple RLC SDUs if one original RLC SDU has been segmented into multiple received RLC SDUs, and may include storing the RLC SN or PDCP SN of the received RLC PDU, and recording the RLC PDU lost due to reordering.

[0572] NR MAC S40 or S55 can be connected to multiple NR RLC layer devices configured in one UE, and the main functions of NR MAC may include the following functions.

[0573] - Mapping between logical channels and transport channels

[0574] -Multiplexing / demultiplexing of MAC SDU

[0575] -Dispatch information report

[0576] - Error correction through ARQ

[0577] - Priority handling between logical channels of a UE

[0578] - Prioritize UEs through dynamic scheduling

[0579] -MBMS service identifier

[0580] -Transmission format selection

[0581] -filling

[0582] The NR PHY layer S45 or S50 may perform operations of channel coding and modulating upper layer data to obtain OFDM symbols and deliver the OFDM symbols through a radio channel, or demodulate OFDM symbols received through a radio channel, channel-decode the OFDM symbols, and deliver the OFDM symbols to an upper layer.

[0583] The detailed structure of the radio protocol structure may vary depending on the carrier (or cell) operation scheme. For example, in the case where the base station transmits data to the UE based on a single carrier (or cell), the base station and the UE may use a protocol structure having a single structure with respect to each layer, such as S00. On the other hand, in the case where the base station transmits data to the UE based on carrier aggregation (CA) using multiple carriers in a single TRP, the base station and the UE may use a protocol structure having a single structure up to the RLC, but multiplexing the PHY layer through the MAC layer, such as S10. As another example, in the case where the base station transmits data to the UE based on dual connectivity (DC) using multiple carriers in multiple TRPs, the base station and the UE may use a protocol structure having a single structure up to the RLC, but multiplexing the PHY layer through the MAC layer, such as S20.

[0584] With reference to the above description of PDCCH and beam configuration, current Rel-15 and Rel-16 NR systems do not support PDCCH retransmission, and therefore, achieving the required reliability in scenarios requiring high reliability, such as URLLC, can be difficult. The present disclosure can improve UE PDCCH reception reliability by providing a method for retransmitting PDCCHs using multiple transmission points (TRPs). The specific method is described below through the following embodiments.

[0585] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The content of the present disclosure can be applied to FDD and TDD systems. As used herein, upper layer signaling (or higher layer signaling) is a method for transmitting a signal from a base station to a UE using a downlink data channel of the physical layer, or from a UE to a base station using an uplink data channel of the physical layer, and may also be referred to as "RRC signaling," "PDCP signaling," or "Media Access Control (MAC) Control Element (MAC CE)."

[0586] In the following, in the present disclosure, the UE may use various methods to determine whether collaborative communication is applied, for example, the PDCCH to which the PDSCH to which collaborative communication is applied is allocated has a specific format, or the PDCCH to which the PDSCH to which collaborative communication is applied includes a specific indicator indicating whether collaborative communication is applied, or the PDCCH to which the PDSCH to which collaborative communication is applied is allocated is scrambled by a specific RNTI, or it is assumed that collaborative communication is applied within a specific range indicated by an upper layer. In the following, for ease of description, it will be assumed that the NC-JT case refers to a case in which the UE receives a PDSCH to which collaborative communication is applied based on conditions similar to those described above.

[0587] Hereinafter, determining the priority between A and B may be variously described as, for example, selecting an entity with a higher priority and performing an operation corresponding thereto according to a predetermined priority rule, or omitting or discarding an operation regarding an entity with a lower priority.

[0588] Hereinafter, the above examples may be described through several embodiments, but they are not independent of each other, and one or more embodiments may be applied simultaneously or in combination.

[0589] [About NC-JT]

[0590] According to an embodiment of the present disclosure, in order to receive PDSCH from multiple TRPs, the UE may use non-coherent joint transmission (NC-JT).

[0591] Unlike traditional systems, 5G wireless communication systems can support not only services requiring high transmission rates, but also services with very short transmission delays and services requiring high connection density. In a wireless communication network that includes multiple cells, transmission and reception points (TRPs), or beams, cooperative communication (coordinated transmission) between each cell, TRP, and / or beam can meet various service requirements by enhancing the strength of the signal received by the UE or efficiently performing interference control between each cell, TRP, and / or beam.

[0592] Joint transmission (JT) is a representative transmission technology for coordinated communication, and can increase the strength or throughput of the signal received by a UE by transmitting the signal to one UE via different cells, TRPs and / or beams. Here, the channels between each cell, TRP and / or beam and the UE may have different characteristics, and specifically, non-coherent joint transmission (NC-JT) supporting non-coherent precoding between each cell, TRP and / or beam may require separate precoding, MCS, resource allocation, and TCI indication according to the channel characteristics of each link between each cell, TRP and / or beam and the UE.

[0593] The above-mentioned NC-JT transmission can be applied to at least one of the downlink data channel (Physical Downlink Shared Channel (PDSCH)), the downlink control channel (Physical Downlink Control Channel (PDCCH)), the uplink data channel (Physical Uplink Shared Channel (PUSCH)), and the uplink control channel (Physical Uplink Control Channel (PUCCH)). During PDSCH transmission, transmission information such as precoding, MCS, resource allocation, and TCI is indicated via DL DCI. For NC-JT transmission, this transmission information should be indicated independently for each cell, TRP, and / or beam. This significantly increases the payload required for DL ​​DCI transmission, which may adversely affect the reception performance of the PDCCH used to transmit the DCI. Therefore, to support JT of PDSCH, a careful trade-off between the amount of DCI information and the reception performance of control information is required.

[0594] Figure 16 An example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to an embodiment of the present disclosure is shown. Specifically, Figure 16 An example of antenna port configuration and resource allocation for PDSCH transmission using cooperative communication in a wireless communication system according to an embodiment of the present disclosure is shown.

[0595] refer to Figure 16 , an example of PDSCH transmission is described for each joint transmission (JT) scheme, and an example of radio resource allocation for each TRP is shown.

[0596] refer to Figure 16 , shows an example N000 for supporting coherent joint transmission (C-JT) with interfering coding between corresponding cells, TRPs or / and beams.

[0597] With C-JT, TRP A N005 and TRP B N010 transmit a single piece of data (PDSCH) to UE N015, and joint precoding can be performed across multiple TRPs. This can indicate that DMRS is transmitted via the same DMRS port, so that TRP A N005 and TRP B N010 transmit the same PDSCH. For example, TRP A N005 and TRP B N010 can transmit DMRS to the UE via DMRS port A and DMRS port B, respectively. In this case, the UE can receive a piece of DCI information for receiving a PDSCH demodulated based on the DMRS transmitted via DMRS port A and DMRS port B.

[0598] Figure 16 An example N020 is shown of supporting non-coherent joint transmission (NC-JT) with non-coherent intercoding between corresponding cells, TRPs and / or beams for PDSCH transmission.

[0599] In the case of NC-JT, PDSCH is transmitted to UE 1035 per cell, per TRP and / or per beam, and separate precoding can be applied to each PDSCH. The corresponding cells, TRPs and / or beams can transmit different PDSCHs or different PDSCH layers to the UE, thereby improving throughput compared to single cell, TRP and / or beam transmission. In addition, each cell, TRP and / or beam can repeatedly transmit the same PDSCH to the UE, thereby improving reliability compared to single cell, TRP and / or beam transmission. For ease of description, cells, TRPs and / or beams may be collectively referred to as TRPs.

[0600] In this case, various radio resource allocations can be considered, such as the case N040 where the frequency and time resources used in multiple TRPs for PDSCH transmission are the same, the case N045 where the frequency and time resources used in multiple TRPs do not overlap at all, and the case N050 where some of the frequency and time resources used in multiple TRPs overlap.

[0601] In order to support NC-JT, DCIs of various forms, structures, and relationships may be considered to simultaneously allocate multiple PDSCHs to a UE.

[0602] Figure 17 An example of downlink control information (DCI) configuration for cooperative communication in a wireless communication system according to an embodiment of the present disclosure is shown. Specifically, Figure 17 A diagram illustrating an example of a configuration of downlink control information (DCI) for NC-JT according to an embodiment of the present disclosure is shown, where corresponding TRPs transmit different PDSCHs or different PDSCH layers to a UE.

[0603] refer to Figure 17 , Case #1 N100 is when different N-1 PDSCHs are transmitted from N-1 additional TRPs (TRP#1 to TRP#N-1) in addition to the serving TRP (TRP#0) used during a single PDSCH transmission, the control information of the PDSCH transmitted in the additional N-1 TRPs is transmitted independently of the control information of the PDSCH transmitted in the serving TRP. That is, the UE can obtain the control information of the PDSCH transmitted from different TRPs (TRP#0 to TRP#N-1) via independent DCI fragments (DCI#0 to DCI#N-1). The formats between independent DCI fragments can be the same or different, and the payloads between DCI fragments can also be the same or different. In the above case #1, the freedom of PDSCH control or allocation can be fully guaranteed, but when the respective fragments of DCI are transmitted by different TRPs, differences between DCI coverage may occur, and reception performance may deteriorate.

[0604] Case #2 N105 is an example in which, in the case where (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used for a single PDSCH transmission, control information (DCI) of the PDSCHs of the (N-1) additional TRPs is transmitted, and each DCI fragment depends on the control information of the PDSCH transmitted from the serving TRP.

[0605] For example, DCI#0, which is control information of the PDSCH transmitted from the serving TRP (TRP#0), includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, but shortened DCI (hereinafter referred to as sDCI) (sDCI#0 to sDCI#N-2), which is control information of the PDSCH transmitted from the collaborative TRPs (TRP#1 to TRP#N-1), may include only some information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2. Therefore, in the case of sDCI for transmitting control information of the PDSCH transmitted from the collaborative TRP, the payload is small compared to normal DCI (nDCI) for transmitting control information related to the PDSCH transmitted from the serving TRP, so that reserved bits can be included compared to nDCI.

[0606] In the above case #2, the degree of freedom of each PDSCH control or allocation can be limited according to the content of the information elements included in sDCl, but the reception capability of sDCI is better than nDCI, and therefore the probability of generating differences between DCI coverage can become lower.

[0607] Case #3 N110 is an example in which, in a case where (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) for a single PDSCH transmission, one control information segment of the PDSCHs of the (N-1) additional TRPs is transmitted, and the DCI depends on the control information of the PDSCHs transmitted from the serving TRP.

[0608] For example, in the case of DCI#0, which is control information for the PDSCH transmitted from the serving TRP (TRP#0), all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 may be included, and in the case of control information for the PDSCH transmitted from the collaborative TRPs (TRP#1 to TRP#(N-1)), only a portion of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 may be aggregated in one "secondary" DCI (sDCI) and transmitted. For example, the sDCI may include at least one HARQ-related information segment, such as frequency domain resource allocation, time domain resource allocation, and MCS of the collaborative TRP. In addition, information not included in the sDCI, such as a bandwidth part (BWP) indicator and a carrier indicator, may follow the DCI of the serving TRP (DCI#0, normal DCI, or nDCI).

[0609] In case #3 N110, each PDSCH control or allocation freedom can be limited according to the content of the information element included in the sDCI, but the sDCI reception performance can be adjustable and the complexity of the UE's DCI blind decoding can be reduced compared to case #1 N100 or case #2 N105.

[0610] Case #4N 115 is a case where N-1 different PDSCHs are transmitted from N-1 additional TRPs (TRP#1 to TRP#N-1) in addition to the serving TRP (TRP#0) used during a single PDSCH transmission, and control information for the PDSCHs transmitted from the N-1 additional TRPs is transmitted in the same DCI (long DCI) as the control information for the PDSCHs transmitted from the serving TRP. That is, the UE can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#N-1) via a single DCI. In case #4N 115, the complexity of the UE's DCI blind decoding may not increase, but the PDSCH control or allocation freedom may be low, so that the number of collaborative TRPs is limited according to the long DCI payload restriction.

[0611] In the following description and embodiments, sDCI may refer to various supplementary DCIs such as shortened DCI, auxiliary DCI or normal DCI (the above-mentioned DCI formats 1_0 and 1_1) including PDSCH control information sent in collaborative TRP, and unless specific restrictions are mentioned, the corresponding description can be similarly applied to various supplementary DCIs.

[0612] In the following description and embodiments, the aforementioned cases #1 N100, #2 N105, and #3 N110, in which one or more DCIs are used for NC-JT support, can be categorized as multi-PDCCH-based NC-JT, while the aforementioned case #4 N115, in which a single DCI (PDCCH) is used for NC-JT support, can be categorized as single-PDCCH-based NC-JT. In multi-PDCCH-based PDSCH transmission, the CORESET used to schedule DCI for the serving TRP (TRP#0) is separated from the CORESET used to schedule DCI for the cooperating TRPs (TRP#1 to TRP#(N-1)). Methods for distinguishing CORESETs include distinguishing by a higher layer indicator for each CORESET and distinguishing by the beam configuration for each CORESET. Furthermore, in single-PDCCH-based NC-JT, a single DCI schedules a single PDSCH with multiple layers rather than multiple PDSCHs, and multiple layers can be transmitted from multiple TRPs. In this case, the association between the layer and the TRP transmitting the corresponding layer may be indicated by a transmission configuration indicator (TCI) indication for the layer.

[0613] In the embodiments of the present disclosure, when actually applied, "collaborative TRP" may be replaced by various terms such as "collaborative plane" or "collaborative beam".

[0614] According to an embodiment of the present disclosure, "a case where NC-JT is applied" may be interpreted differently depending on the situation as "a case where the UE simultaneously receives one or more PDSCHs in one BWP", "a case where the UE simultaneously receives PDSCHs in one BWP based on two or more transmission configuration indicators (TCI) indications", and "a case where the PDSCH received by the UE is associated with one or more DMRS port groups", but for ease of description, it is used through one expression.

[0615] As used herein, the radio protocol structure for NC-JT can be used in various ways depending on the TRP deployment scenario. For example, if there is little or no backhaul delay between the cooperating TRPs, a radio protocol structure similar to Figure 15It is possible to use a method (a CA-like method) based on a structure of MAC layer multiplexing in the manner of reference numeral S10. On the other hand, if the backhaul delay between the cooperative TRPs is so large that the backhaul delay cannot be ignored (for example, when the exchange of information such as CSI, scheduling, and HARQ-ACK between the cooperative TRPs takes 2ms or more), it is possible to use a method based on a structure of MAC layer multiplexing in the manner of reference numeral S10. Figure 15 In a similar manner to reference numeral S20 , a method (DC-like method) for ensuring characteristics robust to delays by using an independent structure for each TRP starting from the RLC layer is possible.

[0616] A UE that supports C-JT / NC-JT can receive C-JT / NC-JT related parameters or setting values ​​from a high-level configuration and set the UE's RRC parameters based on the parameters or setting values. For high-level configuration, the UE can use UE capability parameters, such as tci-StatePDSCH. Here, the UE capability parameters, such as tci-StatePDSCH, can define the TCI states used for PDSCH transmission. The number of TCI states can be configured as 4, 8, 16, 32, 64, and 128 in FR1, and as 64 and 128 in FR2, and a maximum of 8 states that can be indicated by 3 bits of the TCI field of the DCI can be configured in the configured number through the MAC CE message. The maximum value of 128 refers to the value indicated by maxNumberConfiguredTCI statesPerCC in the parameter tci-StatePDSCH included in the UE's capability signaling. In this way, a series of configuration processes from high-level configuration to MAC CE configuration can be applied to the beamforming change command or beamforming indication of at least one PDSCH in one TRP.

[0617] [Multiple TRPs based on multiple DCIs]

[0618] According to an embodiment of the present disclosure, a downlink control channel for NC-JT transmission may be configured based on multiple PDCCHs.

[0619] In multi-PDCCH based NC-JT, when sending DCI for scheduling PDSCH of each TRP, there may be a CORESET or search space separated for each TRP. The CORESET or search space of each TRP may be configured according to at least one of the following configuration cases.

[0620] *Configuration of the high-layer index for each CORESET: The CORESET configuration information configured by the high-layer may include an index value, and for each CORESET, the TRP used to send the PDCCH in the corresponding CORESET may be distinguished by the configured index value. That is, in a set of CORESETs with the same high-layer index value, the same TRP may be considered to send the PDCCH, or to send the PDCCH for scheduling the PDSCH of the same TRP. The index of each CORESET may be named CORESETPoolIndex, and the PDCCH may be considered to be sent from the same TRP in the CORESET configured with the same CORESETPoolIndex value. For a CORESET for which a CORESETPoolIndex value has not yet been configured, it may be considered that a default value has been configured for CORESETPoolIndex, and the default value may be 0.

[0621] *Configuration of multiple PDCCH-Configs: Multiple PDCCH-Configs are configured in one BWP, and each PDCCH-Config may include a PDCCH configuration for each TRP. That is, a CORESET list for each TRP and / or a search space list for each TRP may be included in one PDCCH-Config, and one or more CORESETs and one or more search spaces included in one PDCCH-Config may be considered to correspond to a specific TRP.

[0622] *CORESET beam / beam group configuration: The TRP corresponding to the corresponding CORESET can be distinguished by the beam or beam group configured for each CORESET. For example, if the same TCI state is configured for multiple CORESETs, it can be considered or determined that the CORESETs are transmitted via the same TRP, or the PDCCH for scheduling the PDSCH of the same TRP is transmitted in the corresponding CORESET.

[0623] *Search space beam / beam group configuration: A beam or beam group can be configured for each search space, and the TRP of each search space can be differentiated based on the configured beam or beam group. For example, if the same beam / beam group or TCI state is configured in multiple search spaces, the same TRP can be sent in the corresponding search space. PDCCH, or PDCCH for scheduling PDSCH of the same TRP can be sent in the corresponding search space.

[0624] As described above, by distinguishing CORESET or search space according to TRP, PDSCH and HARQ-ACK information can be classified for each TRP, and based on this, HARQ-ACK codebook can be generated independently for each TRP and PUCCH resources can be used independently.

[0625] The configuration can be independent for each cell or each BWP. For example, although two different CORESETPoolIndex values ​​are configured for the PCell, a CORESETPoolIndex value may not be configured for a specific SCell. In this case, NC-JT can be configured in the PCell, but not in the SCell for which a CORESETPoolIndex value is not configured.

[0626] [Multiple TRPs based on a single DCI]

[0627] According to another embodiment of the present disclosure, a downlink beam for NC-JT transmission may be configured based on a single PDCCH.

[0628] In NC-JT based on a single PDCCH, PDSCHs transmitted by multiple TRPs can be scheduled via one DCI segment. Here, as a method of indicating the number of TRPs that transmit the corresponding PDSCH, the number of TCI states can be used. That is, if the number of TCI states indicated in the DCI for scheduling the PDSCH is two, NC-JT transmission based on a single PDCCH can be considered, and if the number of TCI states is one, single TRP transmission can be considered. The TCI state indicated by the DCI may correspond to one or two TCI states among the TCI states activated by the MAC CE. If the TCI state of the DCI corresponds to two TCI states activated by the MAC CE, the TCI code point indicated by the DCI is associated with the TCI state activated by the MAC CE, and this may correspond to the case where the number of TCI states activated by the MAC CE corresponding to the TCI code point is 2.

[0629] Configuration can be independent for each cell or each BWP. For example, in a PCell, the maximum number of activated TCI states corresponding to one TCI code point is 2, while in a specific SCell, the maximum number of activated TCI states corresponding to one TCI code point may be 1. In this case, it can be considered that NC-JT can be configured in the PCell, but not in the SCell.

[0630] [PHR]

[0631] Figure 18The figure shows the process of controlling the transmission power of UE in a cellular system. Figure 18 In operation 18-10, a UE within the coverage of the base station may perform downlink synchronization with the base station and acquire system information. According to some embodiments, downlink synchronization may be performed using synchronization signals such as the Primary Synchronization Signal / Secondary Synchronization Signal (PSS / SSS) received from the base station. The UE, having performed downlink synchronization, may receive a Master Information Block (MIB) and a System Information Block (SIB) from the base station and acquire system information. In operation 18-15, the UE may perform uplink synchronization with the base station and establish a Radio Resource Control (RRC) connection via a random access procedure. During the random access procedure, the UE may transmit a random access preamble and Message 3 (MSG3) to the base station via an uplink. In this case, uplink transmit power control may be performed when the random access preamble and Message 3 are transmitted. Specifically, the UE may receive parameters for uplink transmit power control from the base station via the acquired system information (e.g., SIB), or may perform uplink transmit power control using predetermined parameters. In another embodiment of the present disclosure, the UE may measure the reference signal received power (RSRP) from the path attenuation estimation signal transmitted by the base station and may estimate the downlink path attenuation value as shown in Equation 7. In addition, the UE may configure the uplink transmission power value for transmitting the random access preamble and Message 3 based on the estimated path attenuation value.

[0632] [Equation 7]

[0633] Downlink path attenuation = base station signal transmission power - RSRP measured by UE

[0634] In Equation 7, the base station signal transmit power refers to the transmit power of the downlink path loss estimation signal transmitted by the base station. The downlink path loss estimation signal transmitted by the base station may be a cell-specific reference signal (CRS) or a synchronization signal block (SSB). If the path loss estimation signal is a cell-specific reference signal (CRS), the base station signal transmit power may indicate the transmit power of the CRS and may be transmitted to the UE via the referenceSignalPower parameter in system information. If the path loss estimation signal is a synchronization signal block (SSB), the base station signal transmit power may indicate the transmit power of the secondary synchronization signal (SSS) and demodulation reference signal (DMRS) transmitted via the PBCH and may be transmitted to the UE via the ss-PBCH-BlockPower parameter in system information. In operations 18-20, the UE may receive RRC parameters for uplink transmit power control from the base station via UE-specific RRC or common RRC. In this case, the received transmit power control parameters may differ depending on the uplink channel type and signal type. That is, the transmit power control parameters applied to the transmission of the Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel (PUSCH), and Sounding Reference Signal (SRS) may differ from one another. Furthermore, as described above, the transmit power control parameters received by the UE from the base station via the SIB before RRC connection establishment, or the transmit power control parameters used by the UE as predetermined values ​​before RRC connection establishment, may be included in the RRC parameters transmitted from the base station after RRC connection establishment. The UE may use the RRC parameter values ​​received from the base station after RRC connection establishment to control uplink transmit power. In operation 18-25, the UE may receive a path loss estimation signal from the base station. More specifically, after the UE's RRC connection is established, the base station may configure a Channel State Information Reference Signal (CSI-RS) as the UE's path loss estimation signal. In this case, the base station may transmit information regarding the transmit power of the CSI-RS to the UE via the powerControlOffsetSS parameter in UE-specific RRC information. Here, powerControlOffsetSS may indicate the transmit power difference (offset) between the SSB and the CSI-RS. In operation 18-30, the UE may estimate the downlink path loss value and configure the uplink transmit power value. More specifically, the UE may measure the downlink RSRP using the CSI-RS and estimate the downlink path loss value using Equation 7 using information about the transmit power of the CSI-RS received from the base station. Furthermore, the UE may configure the uplink transmit power value for PUCCH, PUSCH, and SRS transmission based on the estimated downlink path loss value. In operation 18-35, the UE may perform a power headroom report (PHR) to the base station.The power headroom may indicate the difference between the UE's current transmit power and the UE's maximum output power. In operation 18-40, the UE may optimize system operations based on the reported power headroom. For example, if the power headroom value reported by a specific UE to the base station is a positive value, the base station may allocate more resource blocks (RBs) to the UE, thereby increasing system throughput. In operation 18-45, the UE may receive a transmit power control (TPC) command from the base station. If the power headroom value reported by the specific UE to the base station is a negative value, the base station may allocate fewer resources to the UE or reduce the UE's transmit power via TPC. This may increase system throughput or reduce unnecessary power consumption of the UE. In operation 18-50, the UE may update its transmit power based on the TPC command. In this case, the TPC command may be sent to the UE via UE-specific DCI or group-common DCI. Therefore, the base station may dynamically control the UE's transmit power via the TPC command. In operation 18-55, the UE may perform uplink transmission based on the updated transmit power.

[0635] [PUSCH power control]

[0636] The PUSCH transmission power may be determined by the following Equation 8.

[0637] [Equation 8]

[0638]

[0639] In Equation 8, It represents the maximum transmit power configured for the UE at PUSCH transmission opportunity i relative to carrier f of serving cell c. represents a reference transmission power configuration value according to an activated uplink bandwidth part (BWP) b of a carrier f of a serving cell c, and has different values ​​according to various transmission types j. It may have various values ​​according to the case where PUSCH transmission corresponds to Message 3 PUSCH for random access, or the case where the PUSCH is a configured grant PUSCH, or according to a scheduled PUSCH. Indicates the frequency to which the PUSCH is allocated. It represents a compensation ratio value of the path loss of the UL BWP b of the carrier f serving the cell c and may be configured by a higher signal and may have different values ​​according to j. represents the downlink path loss estimate of the UL BWP b of carrier f of serving cell c, and uses the value measured by the reference signal in the activated downlink bandwidth portion. The reference signal can be an SS / PBCH block or a CSI-RS. The downlink path loss can be calculated as described above in Equation 7. In another embodiment of the present disclosure, represents the downlink path loss value and corresponds to the path loss calculated by the UE as given in Equation 7. Depending on the higher-level signal configuration, the UE calculates the path loss based on the reference signal resources associated with the SS / PBCH block or CSI-RS. As the reference signal resource, one of various reference signal resource sets can be selected through the higher-level signal or L1 signal, and the UE can calculate the path loss based on the reference signal resource. is a value determined by the modulation and coding scheme (MCS) value of the PUSCH at the PUSCH transmission opportunity i of the UL BWP b of the carrier f of the serving cell c. Indicates the power control adaptive value, and the power value can be dynamically controlled through TPC commands.

[0640] TPC commands are divided into accumulation mode and absolute mode, and one of the two modes can be determined by a higher signal. The accumulation mode is a mode in which the currently determined power control adaptation value is accumulated to the value indicated by the TPC command, and the power control adaptation value can be increased or decreased according to the TPC command, and has the following relationship: . The absolute mode has a value determined by the TPC command regardless of the currently determined power control adaptation value and has Table 44 below shows the values ​​that can be indicated by the TPC command.

[0641] [Table 44] TPC command

[0642] [Table 44]

[0643]

[0644] [PUCCH power control]

[0645] The following Equation 9 is an equation for determining PUCCH transmission power.

[0646] [Equation 9]

[0647]

[0648] [dBm]

[0649] In Equation 9, Indicates the reference transmit power configuration value and can be used according to various transmission types has different values ​​and can be changed by a higher signal such as RRC or MAC CE. If the value is changed via MAC CE and HARQ-ACK for the PDSCH on which MAC CE has been received is sent in slot k, the UE determines that the UE isoffset Start applying the value. k offset It has different values ​​according to the corresponding subcarrier spacing and may have, for example, 3 ms. Indicates the size of the frequency resource region to which the PUCCH is allocated. represents the path attenuation estimation value of the UE and is calculated by the UE based on various CSI-RS or specific reference signals in SS / PBCH according to the higher signal configuration and according to the type as described above in Equation 7. Applicable to repeated transmission of PUCCH. Applicable to repeated transmission of PUCCH.

[0650] [NES Time Domain]

[0651] There are various methods to reduce the power consumption of a base station. A representative example is a method of transmitting and receiving signals within limited time resources. The base station can avoid using the power required for transmission and reception by not transmitting or receiving signals for a predetermined period of time.

[0652] Cell DTX can be divided into a first duration during which signals are periodically transmitted from the base station's perspective, and a second duration during which no signals are transmitted. The first duration can be referred to as the active duration, and the second duration can be referred to as the inactive duration. During the second duration, the UE may receive no signals, or may receive only some important signals. For example, 1) the UE may receive no signals during the second duration. Alternatively, 2) the UE may receive only synchronization signals (SSBs) during the second duration. Alternatively, 3) the UE may receive synchronization signals (SSBs) and data that do not require HARQ feedback, as well as control information indicating the corresponding data information, during the second duration. Alternatively, 4) the UE may receive synchronization signals (SSBs) and data that do not require HARQ feedback, as well as control information indicating the corresponding data information, as well as reference signals during the second duration. Here, the reference signal (RS) can correspond to at least one of DMRS, CSI-RS, and PRS. Alternatively, other reference signals used for channel estimation can correspond to RSs. Alternatively, 5) the UE may receive a synchronization signal (SSB) and data that does not require HARQ feedback, control information indicating corresponding data information in the second duration, a reference signal, a PDCCH present in the UE common search space (CSS), and related data information. Here, the reference signal (RS) may correspond to at least one of a DMRS, a CSI-RS, and a PRS. Alternatively, other reference signals used for channel estimation may correspond to RS.

[0653] Cell DRX can be divided into a first duration during which signals are periodically received from the base station's perspective, and a second duration during which signals are not received. The first duration can be referred to as the active duration, and the second duration can be referred to as the inactive duration. During the second duration, the UE may not transmit any signals, or may only transmit some important signals. For example, 1) the UE may not transmit any signals during the second duration. Alternatively, 2) the UE may only transmit PRACH and Msg.3 PUSCH during the second duration. Alternatively, 3) the UE may only transmit PRACH, PUSCH including Message 3 information, and a reference signal during the second duration. Here, the reference signal may correspond to SRS or another reference signal used for uplink channel estimation. Alternatively, 4) the UE may only transmit PRACH, PUSCH including Message 3 information, a reference signal, and a periodically transmitted signal during the second duration. Here, the reference signal may correspond to SRS or another reference signal used for uplink channel estimation. Here, the periodically transmitted signal may correspond to SR, CSI, or a configured granted PUSCH.

[0654] The base station can be used as a transmitter and the UE can be used as a receiver. That is, the UE can be a transmitter or the base station can be a receiver.

[0655] Figure 19 is a diagram illustrating cycles and durations of cell DTX and cell DRX in a wireless communication system according to an embodiment of the present disclosure.

[0656] Cell DTX and cell DRX may have a common period (PERIOD) and a common first duration (ACTIVE) and second duration (NON-ACTIVE), such as Figure 19 Alternatively, the cell DTX and the cell DRX may have different periods (PERIODs) and different first durations (ACTIVE) and second durations (NON-ACTIVE), as shown in FIG. Figure 19 As shown in 1902. Alternatively, cell DTX and cell DRX may have a common period (PERIOD) but different first durations (ACTIVE) and second durations (NON-ACTIVE). Since cell DTX corresponds to a case where the base station does not periodically transmit a signal during the second duration (NON-ACTIVE), the UE may define the duration as not receiving a signal such as UE DRX. Since cell DRX corresponds to a case where the base station does not periodically receive a signal during the second duration (NON-ACTIVE), the UE may define the duration as not transmitting a signal such as UE DTX.

[0657] Since cell DTX corresponds to a situation where the base station does not transmit during the second duration (NON-ACTIVE), from the UE's perspective, other signals may overlap with the second duration. If the corresponding signal is a downlink signal and the second duration is preconfigured by an L2 signal, such as RRC, the UE may consider the semi-static UL signal to overlap with the corresponding signal and may cancel signal reception. If the corresponding signal is a downlink signal and the second duration is indicated by an L1 signal, such as DCI, the UE may consider the semi-static flexible symbols indicated by the dynamic SFI to be UL. Thereafter, the UE may consider them to overlap with the corresponding signal and may cancel signal reception. A processing timeline for canceling reception may be defined. For example, immediately after receiving the L1 signal, the UE may or may not cancel signal reception within a predetermined duration (T1), and may cancel signal reception after T1. If the corresponding signal is an uplink signal and the second duration is preconfigured by an L2 signal, such as RRC, the UE may consider the semi-static DL signal to overlap with the corresponding signal and may cancel signal transmission. If the corresponding signal is an uplink signal and the second duration is indicated by an L1 signal such as a DCI, the UE may consider the semi-static flexible symbol indicated by the dynamic SFI to be DL. Thereafter, the UE may consider it to overlap with the corresponding signal and may be able to cancel transmission of the signal. A processing timeline for canceling transmission may be defined. For example, immediately after receiving the L1 signal, the UE may or may not cancel transmission of the signal within a predetermined duration (T2), and may be able to cancel transmission of the signal after the T2 duration.

[0658] Since cell DRX corresponds to a situation where the base station does not perform reception during the second duration (NON-ACTIVE), from the UE's perspective, other signals may overlap with the second duration. If the corresponding signal is a downlink signal and the second duration is pre-configured by an L2 signal, such as RRC, the UE may consider the semi-static UL signal to overlap with the corresponding signal and may cancel signal reception. If the corresponding signal is a downlink signal and the second duration is indicated by an L1 signal, such as DCI, the UE may consider the semi-static flexible symbols indicated by the dynamic SFI to be UL. The UE may then consider them to overlap with the corresponding signal and may cancel signal reception. A processing timeline for canceling reception may be defined. For example, immediately after receiving the L1 signal, the UE may or may not cancel signal reception within a predetermined duration (T1), and may cancel signal reception after T1. If the corresponding signal is an uplink signal and the second duration is pre-configured by an L2 signal, such as RRC, the UE may consider the semi-static DL signal to overlap with the corresponding signal and may cancel signal transmission. If the corresponding signal is an uplink signal and the second duration is indicated by an L1 signal such as a DCI, the UE may consider the semi-static flexible symbol indicated by the dynamic SFI to be DL. Thereafter, the UE may consider it to overlap with the corresponding signal and may be able to cancel transmission of the signal. A processing timeline for canceling transmission may be defined. For example, immediately after receiving the L1 signal, the UE may or may not cancel transmission of the signal within a predetermined duration (T2), and may be able to cancel transmission of the signal after the T2 duration.

[0659] [NES space domain]

[0660] Methods for limiting the number of transmit / receive antennas installed in a base station can be used to reduce base station power consumption. For example, if a base station with 64 transmit / receive antennas uses only 32 transmit / receive antennas to transmit / receive signals under certain conditions, the power consumption required for antenna operation can theoretically be reduced by at least half. The base station may be able to notify the UE whether the number of transmit / receive antennas has been adjusted through separate L1 or L2 signals.

[0661] [Introduction to the embodiment]

[0662] Hereinafter, in the above-mentioned method for reducing power consumption of a base station, a method for operating a UE when multiple DL semi-persistent scheduling (SPS) resources may overlap and exist when DTX / DRX is applied, a method for operating a UE when processing HARQ-ACK information for DL ​​SPS, and a method for operating a UE when retransmitting HARQ-ACK information will be described. Here, DL SPS refers to a method in which a UE periodically receives a PDSCH without requiring a separate DCI.

[0663] <First embodiment: Method for resolving overlap of multiple DL SPSs in cell DTX>

[0664] Figure 20 A method for selecting a DL SPS to be received by a UE according to an embodiment of the present disclosure is shown.

[0665] In the first embodiment of the present disclosure, when multiple DL SPSs exist, it is impossible for the UE to simultaneously receive two or more DL SPSs within one cell and one BWP, so a method for selecting DL SPSs is required. Here, it may be necessary to additionally consider the case of overlapping with cell DTX. Figure 20 The method by which the UE selects a DL SPS to be received according to the first embodiment of the present disclosure is shown. Basically, in the case where there are multiple DL SPSs, the method by which the UE selects a DL SPS to be received (excluding overlapping DL SPSs) is as follows [Table 45].

[0666] [Table 45]

[0667]

[0668] For reference Figure 20 In the above case, when the maximum possible number of PDSCHs is 3, the UE will ultimately select and receive SPS index 0, SPS index 1, and SPS index 3 according to [Table 45]. This is a method that does not consider the first duration and the second duration of cell DTX, and the following describes a method for selecting a DL SPS to be received by the UE when cell DTX is applied. <Example 1-1: Case 1 of configuring DTX by RRC>

[0669] According to an embodiment of the present disclosure, when a first duration (ACTIVE) and a second duration (NON-ACTIVE) of cell DTX are configured via RRC, the UE can first resolve the overlap of DL SPS resources for the remaining candidate DL SPSs before selecting a DL SPS to receive, excluding those that overlap with the second duration in terms of time resources. In this way, the UE can exclude DL SPSs that may not be pre-received based on cell DTX from the candidate DL SPS set. For example, the UE can select a DL SPS to receive while applying cell DTX in the manner shown in Table 46 below.

[0670] [Table 46]

[0671]

[0672] For reference Figure 20 In the above case, when the maximum possible number of PDSCHs is 3, the UE will eventually select and receive SPS index 2 and SPS index 4 according to [Table 46]. <Example 1-2: Case 2 of configuring DTX through RRC>

[0673] According to an embodiment of the present disclosure, when a first duration (ACTIVE) and a second duration (NON-ACTIVE) of cell DTX are configured via RRC, the UE may exclude DL SPS resources that overlap with the second duration in terms of time resources after selecting a DL SPS to receive. For example, the UE may be able to select a DL SPS to receive when cell DTX is applied in the manner shown in Table 47 below.

[0674] [Table 47]

[0675]

[0676] For reference Figure 20 In the above case, when the maximum possible number of PDSCHs is 3, the UE will eventually select and receive SPS index 3 according to [Table 47]. <Example 1-3: Case 1 of DTX Indicated by DCI>

[0677] According to an embodiment of the present disclosure, when a first duration (ACTIVE) and a second duration (NON-ACTIVE) of cell DTX can be indicated by DCI, the UE can determine whether the first duration or the second duration occurs through a DCI search. Here, when the second duration information is determined through a DCI search and overlaps with one or more DL SPS resources, the UE can first exclude candidate DL SPS resources that overlap with the second duration in terms of time resources from the DL SPS set as described above in Embodiment 1-1.

[0678] <Example 1-4: Case 2 of Indicating DTX by DCI>

[0679] According to an embodiment of the present disclosure, when a first duration (ACTIVE) and a second duration (NON-ACTIVE) of cell DTX can be indicated by DCI, the UE can determine whether the first duration or the second duration occurs through a DCI search. Here, when the second duration information is determined through a DCI search and overlaps with one or more DL SPS resources, the UE can first exclude candidate DL SPS resources that overlap with the second duration in terms of time resources from the DL SPS set by considering the last DL SPS as described above in Embodiments 1-2.

[0680] <Example 1-5: Case 3 of Indicating DTX by DCI>

[0681] According to an embodiment of the present disclosure, if the first duration (ACTIVE) and second duration (NON-ACTIVE) of a cell's DTX can be indicated by a DCI, the UE can determine whether the first duration or the second duration occurred through a DCI search. If the UE misses the DCI indicating the first and second durations, problems may arise when selecting candidate DL SPS resources because the UE does not know accurate information about the second duration. Therefore, the UE can support at least one of the following various methods to address this issue.

[0682] Method A-1: ​​This method includes candidate DL SPS resources located before X symbols after the last symbol of the PDCCH including the corresponding DCI information in the DL SPS set, and does not include candidate DL SPS resources located in subsequent symbols in the DL SPS set. This method can be applied in step 1 or after step 4, as explained using the example in Table 45.

[0683] -Method A-2: This method assumes that all durations that can be indicated by the corresponding DCI are the first duration. That is, it is determined that the second duration is not applied. This method is the same as [Table 45].

[0684] Method A-4: This method assumes that all durations that can be indicated by all DCIs are the second duration. Therefore, the UE does not receive all DL SPS resources present in the corresponding duration. Furthermore, since the UE does not receive DL SPS resources, it may not report HARQ-ACK information related to the DL SPS resources.

[0685] <Example 1-6: SPS Resource Configuration for Cell DTX>

[0686] According to an embodiment of the present disclosure, the base station may provide different DL SPS resource sets to the UE when cell DTX is applied and when cell DTX is not applied. Figure 20 , when cell DTX is not applied, SPS indexes 0, 1, 2, 3, 4, and 7 may be considered as candidate DL SPS resource domains. On the other hand, when cell DTX is applied, it may be determined that only SPS index 3 is valid, or a separate SPS resource may be determined. There may be only one corresponding SPS resource per time slot, or there may be multiple SPS resources. The application of the applied cell DTX means that the UE has cell DTX duration information pre-periodically configured by an L1 signal or an L2 signal. Not applying cell DTX may mean only the first duration (ACTIVE) or the absence of an L1 signal or an L2 signal indicating cell DTX.

[0687] Alternatively, the above-described embodiments are merely examples, and combinations of all or some of the embodiments may be possible.

[0688] <Example 2: HARQ-ACK Delay Operation Method in Cell DRX>

[0689] Figure 21 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0690] A method for a UE to apply HARQ-ACK delay in case of configured cell DRX according to an embodiment of the present disclosure will be described. Before explaining HARQ-ACK delay, an operation for DL ​​SPS is further explained as follows.

[0691] DL SPS means that DL SPS (PDSCH) resources are received periodically without separate DCI scheduling. Therefore, the UE may be able to send HARQ-ACK feedback for DL ​​SPS periodically received on periodically allocated PUCCH resources. However, in a TDD environment, since the UE can perform downlink reception or uplink transmission only in a specific time slot, there may be a case where HARQ-ACK feedback for DL ​​SPS received in a specific time slot is not sent. Figure 21 In the example in FIG, assuming that DL SPS resources are periodically allocated in each time slot and HARQ-ACK feedback for each DL SPS resource is transmitted in the next time slot, the UE receives DL SPSs 2101, 2103, 2105, and 2107 during the first to fourth DL time slots, but their HARQ-ACK feedback can be transmitted only on PUCCH resource 2117 present in the first UL time slot. That is, since PUCCH resources 2111, 2113, and 2115 overlap with the DL time slot, HARQ-ACK feedback cannot be transmitted on PUCCH resources 2111, 2113, and 2115. Therefore, a HARQ-ACK delay method can be considered to solve this problem.

[0692] Figure 22 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0693] refer to Figure 22As an example, since the existing HARQ-ACK feedback for DL ​​SPS 2201 may not use PUCCH resource 2211, the feedback for DL ​​SPS 2201 may be sent on the next resource 2217 available for HARQ-ACK PUCCH transmission, which is the earliest available resource for subsequent HARQ-ACK PUCCH transmission. Similarly, since the existing HARQ-ACK feedback for DL ​​SPS 2203 may not use PUCCH resource 2213, the feedback for DL ​​SPS 2203 may be sent on the next resource 2217 available for HARQ-ACK PUCCH transmission, which is the earliest available resource for subsequent HARQ-ACK PUCCH transmission. Similarly, since the existing HARQ-ACK feedback for the DL SPS 2205 may not use PUCCH resources 2215, the feedback for the DL SPS 2205 may be sent on the next resource 2217 available for HARQ-ACK PUCCH transmission, which is the earliest available resource for HARQ-ACK PUCCH transmission thereafter. Since the resource on which the actual HARQ-ACK feedback is sent is deferred, this may be referred to as HARQ-ACK deferral. The HARQ-ACK deferral may be determined essentially based on whether the PUCCH resource that will include the HARQ-ACK feedback corresponding to the DL SPS overlaps with a semi-statically configured DL or SSB or CORESET0 and the PDSCH scheduled therethrough. Figure 22 In the example, delay is performed due to overlap with the semi-statically configured DL time slot, and since the earliest available HARQ-ACK PUCCH resource is 2217, HARQ-ACK feedback information for DL ​​SPSs 2201, 2203, 2205, and 2207 is sent on resource 2217. The HARQ-ACK delay method can be determined by the base station based on the UE capability report, and the base station can configure whether to perform HARQ-ACK delay between UEs supporting this method through upper layer signal configuration.

[0694] Figure 23 1 is a diagram illustrating an example of transmitting HARQ-ACK feedback in a case where DL SPS resources are periodically allocated for each time slot in a wireless communication system according to an embodiment of the present disclosure.

[0695] Considering the HARQ-ACK delay method, reference will be made to Figure 23As an example, the method of applying the method when cell DRX is configured is explained. A case where 5 time slots are configured and each time slot is sequentially configured with 1 DL time slot and 4 UL time slots is shown. The first DL time slot is activated, the first to third UL time slots are inactive, and the last UL time slot is activated. Considering that Figure 21 and Figure 22 In the DL SPS configuration considered in

[15] , the UE receives DL SPS 2301 only on the first DL time slot and does not receive DL SPSs 2303, 2305, 2307, and 2309 on the remaining time slots because DL SPSs 2303, 2305, 2307, and 2309 overlap with UL time slots. Furthermore, since the UE only receives DL SPS 2301, it is necessary to send HARQ-ACK feedback for this DL SPS 2301 on PUCCH 2311 according to the existing DL SPS configuration. However, since PUCCH 2311 is a UL time slot and overlaps with the inactivity duration, it may be difficult for the UE to send HARQ-ACK feedback. Therefore, this can be supported by utilizing HARQ-ACK delay.

[0696] As an example, the UE may be able to consider whether the HARQ-ACK PUCCH resources corresponding to the received DL SPS 1) overlap with the semi-statically configured DL or SSB or CORESET0 and the PDSCH scheduled therethrough, or 2) overlap with the UL timeslot but for the second duration (inactive) indicated by the cell DRX configuration. Figure 23 In this example, since the HARQ-ACK PUCCH 2311 resource overlaps with the second duration (NON-ACTIVE) of the UL timeslot, HARQ-ACK feedback transmission is not possible from the UE's perspective. The UE may be able to use PUCCH resources in the first duration (ACTIVE) of the first existing UL timeslot to transmit HARQ feedback for DL ​​SPS 2301. As another example, under the conditions for determining HARQ-ACK delay, the second duration (NON-ACTIVE) may only be possible when indicated by a higher layer signal. As another example, under the conditions for determining HARQ-ACK delay, the second duration (NON-ACTIVE) may only be possible when indicated by an L1 signal. As another example, under the conditions for determining HARQ-ACK delay, the second duration (NON-ACTIVE) may be possible when indicated by an upper layer signal, or when indicated by an L1 signal, or when both signals are considered, which may be selected by a separate higher layer signal.

[0697] As another example, the UE may not perform HARQ-ACK delay and may not send HARQ-ACK feedback included in the PUCCH 2311. In other words, if the second duration indicated by the upper layer signal overlaps with the HARQ-ACK PUCCH 2311 for the DL SPS 2301, the UE does not send the corresponding PUCCH and does not perform separate HARQ-ACK delay. Alternatively, if the second duration indicated by the L1 signal overlaps with the HARQ-ACK PUCCH 2311 for the DL SPS 2301, the UE does not send the corresponding PUCCH and does not perform separate HARQ-ACK delay. Alternatively, if the second duration indicated by the upper layer signal and the L1 signal overlaps with the HARQ-ACK PUCCH 2311 for the DL SPS 2301, the UE does not send the corresponding PUCCH and does not perform separate HARQ-ACK delay.

[0698] As another example, the UE may be able to determine whether to perform HARQ-ACK delay based on the length of the second duration of the UL timeslot. Specifically, if the difference between the timeslot n to which the existing PUCCH including HARQ feedback for DL ​​SPS is allocated and the timeslot m of the PUCCH used to transmit actual HARQ feedback due to HARQ-ACK delay is greater than a predetermined threshold, the UE may be able to discard the HARQ feedback. For example, in the case where the threshold is 2, due to Figure 23 The mn in is 3, so the UE does not send HARQ feedback for DL ​​SPS 2301. As another example, when the threshold is 4, since Figure 23 In the example, mn is 3, so the UE can send HARQ feedback for DL ​​SPS 2301 via PUCCH 2317. The threshold can be configured via a separate upper layer signal. If the HARQ-ACK delay is excessively delayed, the transmission delay time of the corresponding data may increase from the perspective of the UE, which may result in reduced utilization of retransmissions. Therefore, from the perspective of the UE, discarding the HARQ-ACK PUCCH can reduce power consumption, and the base station may be able to use the corresponding uplink resources for other purposes.

[0699] Alternatively, the above-described embodiments are merely examples, and combinations of all or some of the embodiments may be possible.

[0700] <Example 3: HARQ Retransmission Method in Cell DRX Condition>

[0701] Figure 24This is a view showing that in a wireless communication system according to an embodiment of the present disclosure, a UE receives DCI information in a PDCCH resource in one time slot, the DCI indicates HARQ-ACK information, and the DCI indicates an indication of a PUCCH resource in another time slot in which the HARQ-ACK information is to be retransmitted.

[0702] The UE receives the PDSCH and adds and transmits information regarding the successful reception of the data (or TB) in the form of HARQ-ACK feedback included in the PUCCH. There are cases where the UE fails to transmit the PUCCH including the corresponding HARQ-ACK information. As described above, PUCCH resources may overlap with semi-static UL symbols, other higher-priority uplink resources, or a portion of the PUCCH resources may be overlapped by a UL cancellation indication. Alternatively, there are cases where the UE actually transmits a PUCCH but the base station does not correctly receive it. For the reasons described above, if the base station fails to correctly receive the HARQ-ACK information, it is impossible to determine whether the UE has correctly received the TB included in the PDSCH corresponding to the HARQ-ACK information. Therefore, the base station typically conservatively assumes that the PDSCH was not received and performs a retransmission. If the UE had previously correctly received the TB included in the corresponding PDSCH, the UE would transmit an ACK, but the resources used for the PDSCH retransmission by the base station may be unnecessarily used, which may be a waste of system radio resources. Therefore, as a possible method, the base station can instruct the UE to retransmit the HARQ-ACK feedback sent by the UE through DCI without the need for separate PDSCH scheduling. Figure 24 As an example, a UE may receive DCI information in a PDCCH resource in time slot n, and 1) the DCI indicates HARQ-ACK information in a PUCCH resource that the UE previously sent or is about to send in time slot nm, and 2) the DCI indicates that the PUCCH resource through which the HARQ-ACK information is to be retransmitted is in time slot n+k. Thus, the UE may be able to send, in time slot n+k, HARQ-ACK information that the UE previously sent or is about to send in time slot nm. For example, possible values ​​of m may be -7 to 24, and values ​​of k may be 0 to 32. In addition, time slot n+k needs to exist after time slot nm.

[0703] If the cell DTX / DRX configuration is common, and the first duration (ACTIVE) and the second duration (NON-ACTIVE) are periodically configured via an uplink signal or an L1 signal, the second duration may exist between time slot nm and time slot n, as shown in FIG. Figure 24As shown. In this case, if the length of the second duration is greater than 24 time slots, the length is greater than the maximum value of M, 24, and therefore it may be difficult for the base station to receive only HARQ-ACK feedback information from the UE using only DCI. Therefore, various methods can be considered to solve the above problem. For example, when the UE calculates the value of m, the time slot corresponding to the second duration can be excluded from the count. For example, considering the second duration, if the value of m is 26 and the number of time slots included in the second duration is 22, the base station configures the value of m in the DCI sent in time slot n to 4. Therefore, the base station may be able to receive only HARQ-ACK feedback from the UE again within a wider range. In addition, the second duration can be applied only to the duration configured only by the upper layer signal. Alternatively, the second duration can be applied only to the duration configured only by the L1 signal. Alternatively, the second duration can be applied only to the duration configured only by the combination of the upper layer signal and the L1 signal. Similar problems can be applied to n+k in the same way.

[0704] In summary, when the information of the DCI indicated in time slot n indicates m and k offset information, the UE can determine that the number of time slots included in the second duration is not reflected in the corresponding m and k information, respectively. Alternatively, when the information of the DCI indicated in time slot n indicates m and k offset information, the UE can determine that the number of time slots included in the second duration is reflected in the corresponding m and k information, respectively. Alternatively, when the information of the DCI indicated in time slot n indicates m and k offset information, the UE can determine that the number of time slots included in the second duration is reflected or not reflected in the corresponding m and k information, respectively, and this can be determined according to the length of the second duration. For example, in a case where the length of the second duration event is greater than a predetermined threshold, when the information of the DCI indicated in time slot n indicates m and k offset information, the UE can determine that the number of time slots included in the second duration is not reflected in the corresponding m and k information, respectively. For example, when the length of the second duration event is less than a predetermined threshold, when the DCI information indicated in time slot n indicates m and k offset information, the UE may determine that the number of time slots included in the second duration is reflected in the corresponding information of m and k, respectively. The threshold may be a fixed value or may be configured by a separate upper layer signal.

[0705] Figure 25 The structure of a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0706] refer to Figure 25The UE may include a transceiver, a memory (not shown), and a UE processor 2505 (or UE controller or processor). The transceiver generally refers to the UE receiver 2500 and the UE transmitter 2510. The UE transceivers 2500 and 2510, the memory, and the UE processor 2505 may operate according to the above-described communication method of the UE. The components of the UE are not limited to the above examples. For example, the UE may include more or fewer components than those described above. In addition, the transceiver, memory, and processor may be implemented in the form of a single chip.

[0707] The transceiver can transmit and receive signals with the base station. The signals may include control information and data. To this end, the transceiver may include an RF transmitter configured to amplify and up-convert the transmitted signal, an RF receiver configured to perform low-noise amplification and down-conversion of the received signal, and the like. However, this is merely one embodiment of a transceiver, and the components of the transceiver are not limited to an RF transmitter and an RF receiver.

[0708] In addition, the transceiver may receive a signal through a radio channel, output the received signal to the processor, and transmit a signal output from the processor through the radio channel.

[0709] The memory can store programs and data required for UE operation. In addition, the memory can store control information or data included in signals sent / received by the UE. The memory can include storage media such as ROM, RAM, hard disk, CD-ROM and DVD, or a combination of storage media. In addition, the memory can include multiple memories.

[0710] In addition, the processor may control a series of processes so that the UE can operate according to the above-described embodiments. For example, the processor may control the components of the UE to receive DCI configured in two layers in order to simultaneously receive multiple PDSCHs. The processor may include multiple processors, and the processor may execute a program stored in a memory to perform operations to control the components of the UE.

[0711] Figure 26 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown.

[0712] refer to Figure 26The base station may include a transceiver, a memory (not shown), and a base station processor 2605 (or base station controller or processor). The transceiver generally refers to the base station receiver 2600 and the base station transmitter 2610. The base station transceivers 2600 and 2610, the memory, and the base station processor 2605 may operate according to the above-described communication method for the base station. 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 those described above. Furthermore, the transceiver, memory, and processor may be implemented in the form of a single chip.

[0713] The transceiver can transmit and receive signals with the UE. The signals may include control information and data. To this end, the transceiver may include an RF transmitter configured to amplify and up-convert the transmitted signal, an RF receiver configured to perform low-noise amplification and down-conversion of the received signal, and the like. However, this is merely one embodiment of a transceiver, and the components of the transceiver are not limited to the RF transmitter and the RF receiver.

[0714] In addition, the transceiver may receive a signal through a radio channel, output the received signal to the processor, and transmit a signal output from the processor through the radio channel.

[0715] The memory can store programs and data required for base station operation. In addition, the memory can store control information or data included in signals transmitted / received by the base station. The memory can include storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. In addition, the memory can include multiple memories.

[0716] The processor may control a series of processes so that the base station can operate according to the above-described embodiments of the present disclosure. For example, the processor may control the components of the base station to configure DCI including allocation information about multiple PDSCHs configured in two layers and transmit the DCI. The processor may include multiple processors, and the processor may execute the operation of controlling the components of the base station by executing a program stored in a memory.

[0717] The methods disclosed in the claims and / or the methods according to the embodiments described in this disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0718] When the method is implemented by software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors within an electronic device. At least one program includes instructions that cause the electronic device to perform the method according to the various embodiments of the present disclosure as defined in the appended claims and / or disclosed herein.

[0719] 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 devices, compact disk-ROM (CD-ROM), digital versatile disk (DVD) or other types of optical storage devices or magnetic tape cassettes. Alternatively, any combination of some or all of these can form the memory storing the programs. In addition, multiple such memories can be included in the electronic device.

[0720] In addition, the program can be stored in an attachable storage device that can access the electronic device via 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.

[0721] In the above detailed embodiments of the present disclosure, the elements included in the present disclosure are expressed in the singular or plural, depending on the detailed embodiments presented. However, for ease of description, the singular or plural form is appropriately selected according to the presented situation, and the present disclosure is not limited to the elements expressed in the singular or plural. Therefore, an element expressed in the plural may also include a single element, or an element expressed in the singular may also include multiple elements.

[0722] The embodiments of the present disclosure described and illustrated in the specification and the drawings are merely specific examples presented to easily explain the technical content of the present disclosure and to help understand the present disclosure, and are not intended to limit the scope of the present disclosure. That is, it will be apparent 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 also be used in combination as needed. For example, a part of one embodiment of the present disclosure can be combined with a part of another embodiment to operate a base station and a terminal. As an example, a part of the first embodiment of the present disclosure can be combined with a part of the second embodiment to operate a base station and a terminal. In addition, although the above-mentioned embodiments have been described based on an FDD LTE system, other variations based on the technical ideas of the embodiments can also be implemented in other communication systems such as TDD LTE and 5G or NR systems.

[0723] In the drawings describing the method of the present disclosure, the order of description does not always correspond to the order of performing the steps, and the sequential relationship between the steps may be changed, or the steps may be performed in parallel.

[0724] Alternatively, in the drawings describing the method of the present disclosure, some elements may be omitted and only some elements may be included without departing from the basic spirit and scope of the present disclosure.

[0725] Furthermore, in the method of the present disclosure, part or all of the content of each embodiment may be implemented in combination without departing from the basic spirit and scope of the present disclosure.

[0726] Various embodiments of the present disclosure have been described above. The above description of the present disclosure is for illustrative purposes and is not intended to limit the embodiments of the present disclosure to the embodiments set forth herein. Those skilled in the art will understand that other specific modifications and changes to the form of the present disclosure can be easily made without changing the technical ideas or basic features of the present disclosure. The scope of the present disclosure is defined by the appended claims rather than the detailed description above, and the scope of the present disclosure should be interpreted as including all changes or modifications derived from the meaning and scope of the claims and their equivalents.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: receiving, from a base station, first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX), wherein the second configuration information includes information about an activation duration for the UE to receive the SPS PDSCH; as well as At least one SPS PDSCH out of the one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactive duration based on the second configuration information, is received from the base station.

2. The method according to claim 1, further comprising: Sending hybrid automatic repeat request acknowledgement (HARQ-ACK) information of the at least one SPS PDSCH to the base station.

3. The method according to claim 1, further comprising determining the at least one SPS PDSCH, in, Determining the at least one SPS PDSCH includes: The first SPS PDSCH is determined by excluding the SPS PDSCH overlapping with the uplink symbol from among the multiple SPS PDSCHs, and j=0 is configured; determining a second SPS PDSCH as an SPS PDSCH allocated with a lowest index among the first SPS PDSCHs, and increasing a value of j by 1; and A third SPS PDSCH is determined by excluding the second SPS PDSCH and an SPS PDSCH overlapping with the second SPS PDSCH from the first SPS PDSCH.

4. The method according to claim 3, wherein: Increasing the value of j by 1 and determining the third SPS PDSCH are repeatedly performed until no SPS PDSCH is included in the third SPS PDSCH or the value of j becomes equal to a maximum value of PDSCH receivable by the UE within a slot.

5. A method performed by a base station in a wireless communication system, the method comprising: transmitting, to a user equipment (UE), first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX), wherein the second configuration information includes information about an activation duration for the base station to transmit the SPS PDSCH; as well as At least one SPS PDSCH out of the one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactivity duration based on the second configuration information, is transmitted to the UE.

6. The method according to claim 5, further comprising: Hybrid automatic repeat request acknowledgement (HARQ-ACK) information of the at least one SPS PDSCH is received from the UE.

7. The method according to claim 1, in, The first SPS PDSCH is determined by excluding an SPS PDSCH overlapping with an uplink symbol from among a plurality of SPS PDSCHs, and j=0 is configured. wherein a second SPS PDSCH, which is an SPS PDSCH assigned the lowest index, is determined in the first SPS PDSCH, and the value of j is increased by 1, and The third SPS PDSCH is determined by excluding the second SPS PDSCH and an SPS PDSCH overlapping with the second SPS PDSCH from the first SPS PDSCH.

8. The method according to claim 7, wherein: The at least one SPS PDSCH is determined as a result of repeatedly increasing the value of j by 1 and determining the third SPS PDSCH until the third SPS PDSCH no longer includes an SPS PDSCH or the value of j becomes equal to a maximum value of PDSCHs receivable by the UE in a time slot.

9. A user equipment (UE) in a wireless communication system, the UE comprising: transceiver; as well as a controller, coupled to the transceiver, Wherein, the controller is configured as follows: receiving, from a base station, first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX), wherein the second configuration information includes information about an activation duration for the UE to receive the SPS PDSCH; and At least one SPS PDSCH out of the one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactive duration based on the second configuration information, is received from the base station.

10. The UE according to claim 9, wherein: The controller is further configured to send hybrid automatic repeat request acknowledgement (HARQ-ACK) information of the at least one SPS PDSCH to the base station.

11. The UE according to claim 9, wherein: The controller is further configured to, in order to determine the at least one SPS PDSCH: The first SPS PDSCH is determined by excluding the SPS PDSCH overlapping with the uplink symbol from among the multiple SPS PDSCHs, and j=0 is configured; determining a second SPS PDSCH as an SPS PDSCH allocated with a lowest index in the first SPS PDSCH, and increasing a value of j by 1; and A third SPS PDSCH is determined by excluding the second SPS PDSCH and an SPS PDSCH overlapping with the second SPS PDSCH from the first SPS PDSCH.

12. The UE according to claim 9, wherein: The controller is configured to repeatedly increase the value of j by 1 and determine the third SPS PDSCH until the third SPS PDSCH no longer includes an SPS PDSCH or the value of j becomes equal to a maximum value of a PDSCH receivable by the UE in a time slot.

13. A base station in a wireless communication system, the base station comprising: transceiver; as well as a controller, coupled to the transceiver, Wherein, the controller is configured as follows: transmitting, to a user equipment (UE), first configuration information associated with a semi-persistent scheduling (SPS) physical downlink shared channel (PDSCH) and second configuration information associated with cell discontinuous transmission (DTX), wherein the second configuration information includes information about an activation duration for the base station to transmit the SPS PDSCH; and At least one SPS PDSCH out of the one or more SPS PDSCHs based on the first configuration information, excluding an SPS PDSCH overlapping with an inactivity duration based on the second configuration information, is transmitted to the UE.

14. The base station according to claim 13, wherein: The controller is further configured to receive hybrid automatic repeat request acknowledgement (HARQ-ACK) information of the at least one SPS PDSCH from the UE.

15. The base station according to claim 13, in, The first SPS PDSCH is determined by excluding an SPS PDSCH overlapping with an uplink symbol from among a plurality of SPS PDSCHs, and j=0 is configured. wherein a second SPS PDSCH, which is an SPS PDSCH assigned the lowest index, is determined in the first SPS PDSCH, and the value of j is increased by 1, and A third SPS PDSCH is determined by excluding the second SPS PDSCH and an SPS PDSCH overlapping with the second SPS PDSCH from the first SPS PDSCH.

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