Method and apparatus for configuring default beam in wireless communication system

Abstract

A method for a terminal in a wireless communication system is provided. The method includes: receiving a cross-carrier scheduling configuration from a first cell of a base station, the cross-carrier scheduling configuration including information indicating that a carrier indicator field (CIF) is included in downlink control information (DCI); receiving a DCI for scheduling a physical downlink shared channel (PDSCH) from the first cell of the base station, the DCI including the CIF; if the CIF indicates that PDSCH resources are allocated to the first cell, identifying whether a first offset value between the reception of the DCI and the reception of the PDSCH is less than a threshold; and if the first offset value is less than the threshold and the terminal supports default beam selection for the PDSCH, receiving data on the PDSCH from the first cell of the base station based on a quasi-synchronous (QCL) parameter of a control resource set (CORESET) associated with a search space having the lowest CORESET identifier (ID) within the active bandwidth portion (BWP) of the first cell in the most recent time slot, as monitored by the terminal.

Description

Technical Field

[0001] This disclosure relates to wireless communication systems. More specifically, this disclosure relates to methods and apparatus for configuring a beam of light for receiving data in a wireless communication system. Background Technology

[0002] To meet the increasing demands of wireless data services since the deployment of fourth-generation (4G) communication systems, efforts have been made to develop improved fifth-generation (5G) or near-5G communication systems. 5G or near-5G communication systems are also known as "super-4G networks" or "post-LTE systems." Therefore, 5G communication systems are considered to be implemented in higher frequency (mmWave) bands, such as the 60GHz band, to achieve higher data rates. To reduce radio wave propagation loss and increase transmission distance, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antenna technologies in 5G communication systems are discussed. Furthermore, in 5G communication systems, development is underway for system network improvements based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), and receiver interference cancellation. In 5G systems, hybrid FSK and FQAM modulation and sliding window superposition coding (SWSC) have been developed as advanced coding and modulation (ACM), as well as filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0003] The Internet, a human-centric network for generating and consuming information, is evolving into the Internet of Things (IoT), where distributed entities, such as things, exchange and process information without human intervention. A network of everything has emerged, combining IoT technology with big data processing through connections to cloud servers. To realize the IoT, technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required. Recent research has focused on sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC). This IoT environment can provide intelligent Internet technology services that create new value for human life by collecting and analyzing the data generated between connected things. Through the convergence and combination of existing information technology (IT) and various industrial applications, IoT can be applied to a wide range of fields, including smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0004] Correspondingly, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, MTC, and M2M communication can be achieved through beamforming, MIMO, and array antennas. The application of cloud RAN, as a big data processing technology, can also be considered an example of the integration between 5G and IoT technologies.

[0005] The above information is presented as background technology to aid in understanding this disclosure. It is neither determined nor asserted whether any of the above content can be used as prior art in relation to this disclosure. Summary of the Invention

[0006] [Technical Issues]

[0007] This disclosure provides a method for determining a default beam in a wireless communication system without indicating beam information for data reception to the user equipment.

[0008] [Technical Solution]

[0009] The aspects of this disclosure will at least address the aforementioned problems and / or disadvantages, and provide at least the following advantages. Therefore, one aspect of this disclosure is to provide a method for determining a default beam in a wireless communication system, assuming that beam information for data reception is not indicated to the user equipment.

[0010] Other aspects will be set forth in part in the following description and will be apparent in part from the description or may be learned by practice of the embodiments presented.

[0011] According to one aspect of this disclosure, a method performed by a terminal in a wireless communication system is provided. The method performed by the terminal in the wireless communication system includes: receiving a cross-carrier scheduling configuration from a first cell of a base station, the cross-carrier scheduling configuration including information indicating that a carrier indicator field (CIF) is included in downlink control information (DCI); receiving from the first cell of the base station a DCI for scheduling a physical downlink shared channel (PDSCH), the DCI including the CIF; if the CIF indicates that PDSCH resources are allocated to the first cell, identifying whether a first offset value between the reception of the DCI and the reception of the PDSCH is less than a threshold; if the first offset value is less than the threshold and the terminal supports default beam selection for the PDSCH, receiving data on the PDSCH from the first cell of the base station based on a quasi-synchronous (QCL) parameter of a control resource set (CORESET) associated with a search space having the lowest CORESET identifier (ID) within the active bandwidth portion (BWP) of the first cell in the most recent time slot, as monitored by the terminal.

[0012] According to another aspect of this disclosure, a method performed by a base station in a wireless communication system is provided. The method performed by the base station in the wireless communication system includes: transmitting a cross-carrier scheduling configuration from a first cell of the base station to a terminal, the cross-carrier scheduling configuration including information indicating that a CIF is included in a DCI; transmitting a DCI for scheduling a PDSCH from the first cell of the base station to the terminal, the DCI including the CIF; and, if the CIF indicates that PDSCH resources are allocated to the first cell, transmitting first data related to the PDSCH from the first cell of the base station to the terminal, wherein, if a first offset value between the reception of the DCI and the reception of the PDSCH is less than a threshold and the terminal supports default beam selection for the PDSCH, the first data is received based on QCL parameters of the CORESET associated with the search space having the lowest CORESET ID within the BWP of the first cell in the most recent time slot, as monitored by the terminal.

[0013] According to another aspect of this disclosure, a terminal in a wireless communication system is provided. The terminal in the wireless communication system includes a transceiver and a controller coupled to the transceiver. The controller is configured to: receive a cross-carrier scheduling configuration from a first cell of a base station, the cross-carrier scheduling configuration including information indicating that a CIF is included in a DCI; receive a DCI for PDSCH from the first cell of the base station, the DCI including the CIF; if the CIF indicates that PDSCH resources are allocated to the first cell, identify whether a first offset value between the reception of the DCI and the reception of the PDSCH is less than a threshold; and if the first offset value is less than the threshold and the terminal supports default beam selection for PDSCH, receive data on the PDSCH from the first cell of the base station based on the QCL parameters of the CORESET associated with the search space having the lowest CORESET ID within the BWP of the first cell in the most recent time slot monitored by the terminal.

[0014] According to another aspect of this disclosure, a base station in a wireless communication system is provided. The base station in the wireless communication system includes a transceiver and a controller connected to the transceiver. The controller is configured to: transmit a cross-carrier scheduling configuration from a first cell of the base station to a terminal, the cross-carrier scheduling configuration including information indicating that a CIF is included in a DCI; transmit a DCI for scheduling PDSCH from the first cell of the base station to the terminal, the DCI including the CIF; and, if the CIF indicates that PDSCH resources are allocated to the first cell, transmit first data related to PDSCH from the first cell of the base station to the terminal, wherein, if a first offset value between the reception of the DCI and the reception of the PDSCH is less than a threshold and the terminal supports default beam selection for PDSCH, the first data is received based on the QCL parameters of the CORESET associated with the search space having the lowest CORESET ID within the BWP of the first cell in the most recent time slot, as monitored by the terminal.

[0015] [Beneficial Effects]

[0016] According to this disclosure, beam configuration overhead can be reduced by pre-agreeing on default beam values ​​so that user equipment can receive data from base stations in a wireless communication system.

[0017] Other aspects, advantages, and salient features of this disclosure will become apparent to those skilled in the art from the following detailed description of various embodiments disclosed in conjunction with the accompanying drawings. Attached Figure Description

[0018] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 This is a diagram illustrating the time-frequency domain transmission structure of LTE (Long Term Evolution) or Evolved Universal Terrestrial Radio Access (E-UTRA), LTE-Advanced (LTE-A), NR or similar wireless communication systems according to embodiments of this disclosure.

[0020] Figure 2 This is a diagram illustrating the structure of frames, subframes, and time slots in a fifth-generation (5G) system according to an embodiment of the present disclosure;

[0021] Figure 3 An example of the configuration of the bandwidth portion (BWP) in a wireless communication system according to an embodiment of the present disclosure is shown;

[0022] Figure 4 This is a diagram illustrating an example of configuring a control resource set for a downlink control channel in a wireless communication system according to an embodiment of the present disclosure;

[0023] Figure 5 This is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure;

[0024] Figure 6 This is a diagram illustrating an example of allocating frequency domain resources of the Physical Downlink Shared Channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure;

[0025] Figure 7 This is a diagram illustrating an example of allocating time-domain resources of a PDSCH in a wireless communication system according to an embodiment of the present disclosure;

[0026] Figure 8 This is a diagram illustrating an example of allocating time-domain resources according to the subcarrier spacing of the data channel and the control channel in a wireless communication system according to an embodiment of the present disclosure;

[0027] Figure 9 This is a diagram illustrating an example configuration of an antenna port for cooperative communication according to an embodiment of the present disclosure;

[0028] Figure 10 This is a diagram illustrating the process of configuring and activating the PDSCH beam according to an embodiment of this disclosure;

[0029] Figure 11 This is a diagram illustrating the radio protocol structure of the base station and UE under single-cell, carrier aggregation, and dual-connectivity scenarios according to embodiments of this disclosure;

[0030] Figure 12 This is a diagram illustrating an example of PDSCH default beam operation according to an embodiment of the present disclosure;

[0031] Figure 13 This is a diagram illustrating the operation of a base station and user equipment according to embodiments of the present disclosure;

[0032] Figure 14 This is a diagram illustrating the operation of a base station and user equipment according to embodiments of the present disclosure;

[0033] Figure 15 This is a diagram illustrating the operation of a condition-based base station and user equipment according to an embodiment of the present disclosure;

[0034] Figure 16 The structure of a user equipment in a wireless communication system according to an embodiment of the present disclosure is shown; and

[0035] Figure 17 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown.

[0036] Throughout the accompanying drawings, the same reference numerals will be understood to denote the same parts, components, and structures. Detailed Implementation

[0037] The following description, provided with reference to the accompanying drawings, is intended to aid in a full understanding of the various embodiments of this disclosure as defined by the appended claims and their equivalents. Various specific details are included in the following description to aid understanding, but these are to be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of this disclosure. Furthermore, for clarity and brevity, descriptions of well-known functions and constructions may be omitted.

[0038] The terms and words used in the following description and the appended claims are not limited to their literal meaning, but are intended only for the inventors to provide a clear and consistent understanding of this disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of this disclosure is for illustrative purposes only and is not intended to limit the disclosure as defined by the appended claims and their equivalents.

[0039] It should be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context explicitly specifies otherwise. Thus, for example, a reference to “a surface of a component” includes a reference to one or more such surfaces.

[0040] It should be understood that each block shown in the flowchart, and combinations of blocks shown in the flowchart, 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 apparatus to produce a machine, such that the instructions, which execute via the processor of said computer or other programmable data processing apparatus, generate means for performing the functions specified in the flowchart blocks. These computer program instructions can also be stored in a computer-usable or computer-readable storage medium, which can instruct the computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-usable or computer-readable storage medium generate an article of writing including instruction means for implementing the functions specified in the flowchart blocks. These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of executable operations that generate a computer-implemented process to be performed on the computer or other programmable apparatus, such that the instructions executing on the computer or other programmable apparatus provide operations for implementing the functions specified in the flowchart blocks.

[0041] Additionally, each box in the flowchart may represent a module, segment, or portion of code that includes one or more executable instructions for implementing a specific logical function. It should also be noted that in some alternative implementations, the functions shown in the boxes may not occur in a sequential order. For example, two boxes that are actually shown consecutively may execute substantially simultaneously, or these boxes may sometimes execute in reverse order, depending on the functions involved.

[0042] As used herein, "unit" refers to a software or hardware element that performs a predetermined task, such as a field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC). However, "unit" is not always limited to software or hardware. A "unit" may be configured to be stored in addressable storage media or to run one or more processors. Thus, for example, a "unit" includes software elements, object-oriented software elements, class elements or task elements, processes, functions, features, procedures, subroutines, program code snippets, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and parameters. Elements and functions provided by a "unit" may be combined into a smaller number of elements or "units," or may be divided into a larger number of elements and "units." Additionally, elements and "units" may be implemented as one or more central processing units (CPUs) within a reconfigurable device or secure multimedia card. Furthermore, according to some embodiments, a "unit" may include one or more processors.

[0043] The operating principles of this disclosure will be described in detail below with reference to the accompanying drawings. In the following description of this disclosure, detailed descriptions of known functions or configurations incorporated herein will be omitted where such inclusion would unnecessarily obscure the subject matter of this disclosure. The terminology described below is defined in consideration of the functions in this disclosure and may vary depending on the user, the user's intent, or habit. Therefore, the definitions of terms should be determined based on the content throughout the specification. In the following description, a base station is an entity that allocates resources to terminals and may be at least one of a next-generation Node B (gNode B), an evolved Node B (ENode B), a Node B, a base station (BS), a radio access unit, a base station controller, and nodes on a network. Terminals may include user equipment (UE), mobile station (MS), cellular phone, smartphone, computer, or multimedia system capable of performing communication functions. Of course, examples of base stations and terminals are not limited to these. A description of techniques for receiving broadcast information from a base station by a terminal in a wireless communication system will be given below. This disclosure relates to communication technologies and systems for integrating IoT technologies with 5G communication systems designed to support higher data transfer rates than 4G systems. This disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies, such as smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail businesses, security and safety-related services, etc.

[0044] In the following description, for convenience, terms referring to broadcast information, terms referring to control information, terms related to communication coverage, terms referring to state changes (e.g., events), terms referring to network entities, terms referring to messages, terms referring to device elements, etc., are used by way of example. Therefore, this disclosure is not limited to the terms used below, and other terms that refer to the subject matter having equivalent technical meaning may be used.

[0045] In the following description, for ease of description, the terms and names defined in the 3GPP Long Term Evolution (LTE) standard will be used to describe this disclosure. However, this disclosure is not limited to these terms and names and can be equally applied to systems conforming to other standards.

[0046] In addition to typical voice-based services, wireless communication systems have evolved into broadband wireless communication systems that provide high-speed and high-quality packet data services, using communication standards such as 3GPP High Speed ​​Packet Access (HSPA), LTE (Long Term Evolution or Evolved Global Terrestrial Radio Access (E-UTRA)), LTE-A Advanced, LTE-Pro, 3GPP2 High Rate Packet Data (HRPD), Ultra Mobile Broadband (UMB), 802.16e, etc.

[0047] As a typical example of a broadband wireless communication system, the LTE system employs 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 represents the radio link through which a UE or MS transmits data or control signals to a BS (e.g., an eNode B), while the downlink represents the radio link through which the base station transmits data or control signals to the UE. To prevent overlap, i.e., to establish orthogonality, these multiple access schemes separate the data or control information for each user by allocating and operating time-frequency resources for transmitting data or control information for each user.

[0048] As the communication system following LTE, 5G communication systems must freely reflect the various needs of users, service providers, and others, and must support services that meet these diverse needs in parallel. Services considered in 5G communication systems may include enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC).

[0049] According to some implementations, eMBB aims to provide higher data transmission rates than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, from the perspective of a single eNB, eMBB must provide a peak data rate of 20 Gbps in the downlink and 10 Gbps in the uplink. Additionally, 5G communication systems must provide enhanced perceived data rates to the UE. To meet these requirements, improved transmit / receive technologies will be needed, including advanced multiple-input multiple-output (MIMO) transmission technologies. Furthermore, instead of the 2 GHz bandwidth used in current LTE, 5G communication systems utilize a wider frequency bandwidth than 20 MHz in the 3 GHz to 6 GHz or 6 GHz or higher frequency bands, thus achieving the data transmission rates required by 5G communication systems.

[0050] Furthermore, mMTC is being considered in 5G communication systems to support applications such as the Internet of Things (IoT). mMTC requires features such as supporting a large number of UEs within a cell, improving UE coverage, increasing battery life, and reducing UE costs to effectively deliver IoT services. Since IoT provides communication capabilities to various sensors and devices simultaneously, it is essential to support a large number of UEs within a cell (e.g., 1,000,000 UEs / km). 2Additionally, because the UE is likely to be located in shadow areas not covered by the cell due to the characteristics of the service (such as the basement of a building), UEs supporting mMTC may require a wider coverage area compared to other services provided by 5G communication systems. UEs supporting mMTC must be configured as low-cost UEs, and may require long battery life due to the difficulty in frequently replacing their batteries.

[0051] Finally, URLLC, a cellular-based mission-critical wireless communication service used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote healthcare, and emergency alerts, must provide extremely low latency and extremely high reliability. For example, services supporting URLLC must meet an air interface latency of less than 0.5 milliseconds and also require 10- 5 Or even lower packet error rates. Therefore, for services supporting URLLC, 5G systems must provide shorter Transmission Time Intervals (TTIs) than other services and need to be designed to allocate a large amount of resources on the frequency band. However, the above-mentioned mMTC, URLLC, and eMBB are merely examples of different types of services, and this disclosure is not limited to the service types mentioned above.

[0052] The services considered in the aforementioned 5G communication system must be integrated into a single framework before being provided. In other words, for effective resource management and control, it is preferable to integrate the various services into a single system for control and delivery, rather than operating these services independently.

[0053] Furthermore, although this embodiment will be described below using LTE, LTE-A, LTE Pro, or NR systems as examples, this embodiment can be applied to other communication systems with similar technical backgrounds or channel configurations. Additionally, based on the judgment of those skilled in the art, this embodiment can be applied to other communication systems by making some modifications without departing from the scope of this disclosure.

[0054] The frame structure of a 5G system will be described in more detail below with reference to the accompanying drawings.

[0055] Figure 1 This is a diagram illustrating the basic structure of time-frequency resources in a wireless communication system according to an embodiment of the present disclosure.

[0056] refer to Figure 1 , Figure 1 The horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit in the time-frequency domain is the resource element (RE) 1-01, which can be defined as an orthogonal frequency division multiplexing (OFDM) symbol 1-02 in the time domain and a subcarrier 1-03 in the frequency domain. In the frequency domain, continuous... (For example) 12 REs can constitute a resource block (RB) 1-04. In an implementation, multiple OFDM symbols can constitute a subframe 1-10.

[0057] Figure 2 This is a diagram illustrating the structure of frames, subframes, and time slots according to an embodiment of the present disclosure.

[0058] refer to Figure 2 A frame 2-00 may include one or more subframes 2-01, and a subframe 2-01 may include one or more time slots 2-02. For example, a frame 2-00 may be defined as 10 ms. A subframe 2-01 may be defined as 1 ms, in which case a frame 2-00 may include a total of 10 subframes 2-01. A time slot 2-02 or 2-03 may be defined as 14 OFDM symbols (that is, the number of symbols per time slot). A subframe 2-01 may include one or more time slots 2-02 or 2-03, and the number of time slots 2-02 or 2-03 for each subframe 2-01 may vary according to the configuration value μ2-04 or 2-05 of the subcarrier spacing. Figure 2 The examples illustrate the cases where the subcarrier spacing is configured with μ = 0 (2-04) and μ = 1 (2-05). In the case of μ = 0 (2-04), one subframe 2-01 may include one time slot 2-02; in the case of μ = 1 (2-05), one subframe 2-01 may include two time slots 2-03. That is, the number of time slots per subframe... It can vary according to the configured value μ of the subcarrier spacing, and the number of time slots per frame. This can be varied accordingly. Based on the configuration value μ for each subcarrier spacing, and It can be defined as shown in Table 1 below.

[0059] [Table 1]

[0060]

[0061] In NR, a component carrier (CC) or serving cell can include up to 250 RBs. Therefore, in LTE, where the UE always receives the entire serving cell bandwidth, UE power consumption can be severe. To address this, the base station can configure one or more bandwidth portions (BWPs) for the UE, allowing the UE to change the reception domain within the cell. In NR, the base station can configure an "initial BWP" for the UE via the Master Information Block (MIB), where the "initial BWP" is the bandwidth of CORESET#0 (or Common Search Space (CSS)). The base station can then configure the UE's initial BWP (first BWP) via RRC signaling, and later send a notification of one or more BWP configuration information indicated by downlink control information (DCI). Afterward, the base station can send a notification of the BWP ID via DCI, indicating which frequency band will be used by the UE. If the UE does not receive DCI in its currently allocated BWP within a specific time or beyond, the UE reverts to the "default BWP" and attempts to receive DCI.

[0062] Figure 3 This is a diagram illustrating an example of the configuration of the bandwidth portion (BWP) in a wireless communication system according to an embodiment of the present disclosure.

[0063] refer to Figure 3 , Figure 3 An example is shown where UE bandwidth 3-00 may include two bandwidth sections (i.e., bandwidth section #1 (3-05) and bandwidth section #2 (3-10)). The base station may configure one or more bandwidth sections for the UE, and may configure the information shown in Table 2 below for each bandwidth section.

[0064] [Table 2]

[0065]

[0066] In addition to the configuration information described in Table 2, various parameters related to the bandwidth portion can be configured for the UE. The base station can send the above information to the UE via upper-layer signaling (e.g., RRC signaling). At least one of the configured bandwidth portions can be activated. Information regarding whether the configured bandwidth portion is activated can be sent from the base station to the UE semi-statically via RRC signaling or dynamically via MAC control elements (CE) or DCI.

[0067] According to the implementation method, before the base station establishes a Radio Resource Control (RRC) connection via the Master Information Block (MIB), an Initial Bandwidth Part (BWP) for initial access can be configured for the UE. More specifically, the UE can receive configuration information regarding the Control Resource Set (CORESET) and the search space, which can be transmitted via the PDCCH through the CORESET to receive the system information required for initial access via the MIB during the initial access phase. The system information can correspond to the Remaining System Information (RMSI) or System Information Block 1 (SIB1). The Control Resource Set and the search space configured by the MIB can be considered as ID "0".

[0068] The base station can notify the UE of configuration information for control resource set #0 via the MIB, such as frequency allocation information, time allocation information, and mathematical methods. Additionally, the base station can notify the UE of configuration information regarding the monitoring period and timing for control resource set #0 (i.e., configuration information regarding search space #0) via the MIB. The UE can consider the frequency domain configured with control resource set #0 obtained from the MIB as the initial bandwidth portion for initial access. In this case, the identifier (ID) of the initial bandwidth portion can be considered as 0.

[0069] The bandwidth configuration supported by next-generation mobile communication systems (5G or NR systems) can be used for a variety of purposes.

[0070] For example, if the bandwidth supported by the UE is less than the system bandwidth, the bandwidth supported by the UE can be supported by the configuration of the bandwidth portion. For example, in Table 2, the frequency position of the bandwidth portion can be configured for the UE (configuration information 2), so that the UE can send and receive data at a specific frequency position within the system bandwidth.

[0071] As another example, to support different parameter sets, the base station can configure multiple bandwidth sections for the UE. For instance, to support transmitting and receiving data for any UE using subcarrier spacings of 15 kHz and 30 kHz, the two bandwidth sections can be configured to use subcarrier spacings of 15 kHz and 30 kHz, respectively. Frequency division multiplexing can be performed on different bandwidth sections, and the bandwidth section configured with the corresponding subcarrier spacing can be activated when transmitting / receiving data with a specific subcarrier spacing.

[0072] As another example, to reduce UE power consumption, the base station can configure bandwidth portions with different bandwidths for the UE. For instance, if the UE supports a very large bandwidth (e.g., 100MHz) and always transmits and receives data through that bandwidth, it will result in very high power consumption. In particular, unnecessary downlink control channel monitoring over a large 100MHz bandwidth when there is no service is highly inefficient in terms of UE power consumption. Therefore, to reduce UE power consumption, the base station can configure a bandwidth portion with a relatively small bandwidth for the UE (e.g., a 20MHz bandwidth portion). When there is no service, the UE can perform monitoring operations in the 20MHz bandwidth portion, and if data is generated, it can transmit and receive data using the 100MHz bandwidth portion according to the base station's instructions.

[0073] In the method for configuring the bandwidth portion, a UE that has not yet established an RRC connection can receive configuration information regarding the initial bandwidth portion via the Master Information Block (MIB) during the initial access phase. More specifically, the UE can receive the configuration of the Control Resource Set (CORESET) for the downlink control channel from the MIB of the Physical Broadcast Channel (PBCH), through which downlink control information (DCI) for scheduling System Information Blocks (SIBs) can be transmitted. The bandwidth of the Control Resource Set configured via the MIB can be considered as the initial bandwidth portion, and the UE can receive the PDSCH for transmitting SIBs through the configured initial bandwidth portion. The initial bandwidth portion can be used for other System Information (OSI), paging and random access, and SIB reception.

[0074] The following text will describe the synchronization signal (SS) / PBCH block (SSB) of the next-generation mobile communication system (5G or NR system).

[0075] - The SS / PBCH block can indicate a physical layer channel block that includes the primary SS (PSS), secondary SS (SSS), and PBCH. More specifically, the SS / PBCH block can be defined as follows.

[0076] -PSS: This is a reference signal used for downlink time / frequency synchronization and can provide some information about the cell ID.

[0077] -SSS: This is the reference for downlink time / frequency synchronization and provides residual information about the cell ID not provided by PSS. Additionally, it can be used as a reference signal for PBCH demodulation.

[0078] -PBCH: It provides the basic system information necessary for transmitting and receiving data and control channels for the UE. Basic system information may include search space-related control information indicating radio resource mapping information for control channels, control information for independent data channels that schedule the transmission of system information, etc.

[0079] -SS / PBCH Blocks: SS / PBCH blocks can be configured as a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks can be sent within a 5ms time period, and each sent SS / PBCH block can be distinguished by an index.

[0080] The UE can detect the PSS and SSS during the initial access phase and can decode the PBCH. The UE can obtain the MIB from the PBCH and receive the configuration of control resource set #0 through the MIB. The UE can assume a quasi-corresponding (QCL) relationship between the selected SS / PBCH block and the demodulation reference signal (DMRS) transmitted in control resource set #0, thereby monitoring control resource set #0. The UE can receive system information through downlink control information transmitted from control resource set #0. The UE can obtain configuration information related to the random access channel (RACH) necessary for initial access from the received system information. The UE can send a physical RACH (PRACH) to the base station considering the selected SS / PBCH index, and the base station receiving the PRACH can obtain information about the index of the SS / PBCH block selected by the UE. The base station can identify which block the UE has selected from the corresponding SS / PBCH block and monitor the control resource set #0 corresponding to (or associated with) the SS / PBCH block selected by the UE.

[0081] The following text will describe in detail the downlink control information (hereinafter referred to as "DCI") in next-generation mobile communication systems (5G or NR systems).

[0082] In next-generation mobile communication systems (5G or NR systems), scheduling information regarding uplink data (or Physical Uplink Shared Channel (PUSCH)) or downlink data (or Physical Downlink Data Channel (PDSCH)) can be sent from the base station to the UE via DCI. The UE can monitor the DCI format used for backoff and the DCI format used for non-backoff for either PUSCH or PDSCH. The DCI format used for backoff can be configured with predefined fixed fields between the base station and the UE, while the DCI format used for non-backoff may include configurable fields.

[0083] DCI messages are transmitted via the Physical Downlink Control Channel (PDCCH) after channel coding and modulation. Cyclic Redundancy Check (CRC) can be appended to the payload of the DCI message, and the CRC can be scrambled using a Radio Network Temporary Identifier (RNTI) corresponding to the UE identifier. Depending on the purpose of the DCI message (e.g., transmission of UE-specific data, power control commands, random access responses, etc.), different RNTIs can be used to scramble the CRC of the payload appended to the DCI message. That is, the RNTI can be included in the CRC calculation process and then transmitted, but not explicitly. If a DCI message is received via the PDCCH, the UE can use the assigned RNTI to check the CRC. If the CRC check result is correct, the UE can recognize that the message is for the UE.

[0084] For example, SI-RNTI can be used to scramble the DCI used for PDSCH scheduling of System Information (SI). RA-RNTI can be used to scramble the DCI used for PDSCH scheduling of Random Access Response (RAR) messages. P-RNTI can be used to scramble the DCI used for PDSCH scheduling of paging messages. SFI-RNTI can be used to scramble the DCI used for notification transmission of Slot Format Indicator (SFI). TPC-RNTI can be used to scramble the DCI used for notification transmission of Transmit Power Control (TPC). Cell RNTI (C-RNTI) can be used to scramble the DCI used for scheduling UE-specific PDSCH or PUSCH.

[0085] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, in which case CRC can be scrambled using C-RNTI. In an implementation, DCI format 0_0 using C-RNTI to scramble CRC may include the information shown in Table 3 below.

[0086] [Table 3]

[0087]

[0088] DCI format 0_1 ​​can be used as a non-back-off DCI for scheduling PUSCH, in which case CRC can be scrambled using C-RNTI. In an implementation, DCI format 0_1 ​​using C-RNTI to scramble CRC may include the information shown in Table 4 below.

[0089] [Table 4]

[0090]

[0091]

[0092]

[0093] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, in which case CRC can be scrambled using C-RNTI. In an implementation, DCI format 1_0 using C-RNTI scrambled CRC may include the information shown in Table 5 below.

[0094] [Table 5]

[0095]

[0096] Alternatively, DCI format 1_0 can be used as DCI for PDSCH scheduling of RAR messages, in which case CRC can be scrambled using RA-RNTI. DCI format 1_0 using RA-RNTI scrambled CRC can include the information shown in Table 6 below.

[0097] [Table 6]

[0098]

[0099] DCI format 1_1 can be used as a non-back-off DCI for scheduling PDSCH, in which case CRC can be scrambled using C-RNTI. In an implementation, DCI format 1_1 using C-RNTI scrambled CRC may include the information shown in Table 7 below.

[0100] [Table 7]

[0101]

[0102]

[0103] Figure 4 This is a diagram illustrating an example of configuring a control resource set for a downlink control channel in a wireless communication system according to an embodiment of the present disclosure. Figure 4 This is a diagram illustrating an embodiment of transmitting a control resource set (CORESET) for a downlink control channel in a 5G wireless communication system, according to an embodiment.

[0104] refer to Figure 4 , Figure 4 An implementation is shown in which two control resource sets (i.e., control resource set #1 (4-01) is configured with control resource set #2 (4-02)) are configured within a UE bandwidth portion 4-10 in the frequency domain and a timeslot 4-20 in the time domain. Control resource sets 4-01 and 4-02 can be configured within a specific frequency resource 4-03 within the entire UE bandwidth portion 4-10 in the frequency domain. Control resource sets 4-01 and 4-02 can be configured to use one or more OFDM symbols in the time domain and can be defined as a control resource set duration 4-04. Reference Figure 4Control resource set #1 (4-01) is configured to have a duration of two symbols, and control resource set #2 (4-02) is configured to have a duration of one symbol.

[0105] The aforementioned control resource set in next-generation mobile communication systems (5G or NR systems) can be configured via upper-layer signaling (e.g., system information, Master Information Block (MIB), and Radio Resource Control (RRC) signaling) sent from the base station to the UE. Configuring the control resource set for the UE means providing the UE with 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 configuration of the control resource set may include the information shown in Table 8 below.

[0106] [Table 8]

[0107]

[0108]

[0109] In Table 8, the tci-StatesPDCCH (hereinafter referred to as "TCI State") configuration information may include information about one or more Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) block indices or Channel State Information Reference Signal (CSI-RS) indices that have a quasi-correspondence (QCL) relationship with the Demodulation Reference Signal (DMRS) transmitted in the corresponding control resource set.

[0110] One or more different antenna ports (which may be replaced by one or more channels, signals and combinations thereof, but for ease of description, are collectively referred to as “different antenna ports” in the following description of this disclosure) can be associated with each other through the QCL configuration shown in Table 9 below in a wireless communication system.

[0111] [Table 9]

[0112]

[0113]

[0114] Specifically, the QCL configuration can connect two different antenna ports as a relationship between a target antenna port and a reference antenna port (of the QCL). The UE can apply (or assume) all or some of the channel statistical characteristics measured at the reference antenna port when receiving through the target antenna port (e.g., large-scale channel parameters such as Doppler shift, Doppler spread, average delay, delay spread, average gain, spatial Rx (or Tx) parameters, or the UE's receive or transmit spatial filtering coefficients). The target antenna port represents the antenna port used to transmit a channel or signal configured by an upper-layer configuration including the QCL configuration, or the antenna port used to transmit a channel or signal with a TCI state indicating the QCL configuration applied. The reference antenna port represents the antenna port used to transmit a channel or signal indicated (specified) by the parameter "referenceSignal" in the QCL configuration.

[0115] Specifically, the channel statistical characteristics defined by the QCL configuration (indicated by the qcl-Type parameter in the QCL configuration) can be classified according to the QCL type as follows.

[0116] "QCL-Type A": {Doppler frequency shift, Doppler spread, average delay, delay spread}

[0117] "QCL-Type B": {Doppler frequency shift, Doppler spread}

[0118] "QCL-Type C": {Doppler shift, average delay}

[0119] “QCL-Type D”: {Space Rx parameter}

[0120] While the types of QCLs are not limited to the four mentioned above, not all possible combinations will be listed to avoid confusion. QCL-Type A is a type of QCL used when the bandwidth and transmission spacing of the target antenna port are sufficient compared to those of the reference antenna port (i.e., the number of samples and transmission bandwidth / time at the target antenna port are greater than those at the reference antenna port in both the frequency and time domains), making all measurable statistical characteristics in both the frequency and time domains referential. QCL-Type B is a type of QCL used when the bandwidth of the target antenna port is sufficient to measure measurable statistical characteristics in the frequency domain (i.e., Doppler shift and Doppler spread). QCL-Type C is a type of QCL used when the bandwidth and transmission spacing of the target antenna port are insufficient to measure second-order statistics (i.e., Doppler spread and delay spread), and therefore only first-order statistics (i.e., only Doppler shift and average delay) are referential. QCL-Type D is a type of QCL configured when the spatial receiver filter value used when receiving the reference antenna port can be used when receiving the target antenna port.

[0121] Meanwhile, the base station can configure or indicate up to two QCL configurations for a target antenna port through the TCI status configuration shown in Table 10 below.

[0122] [Table 10]

[0123]

[0124] The first QCL configuration in a TCI state configuration can be configured as one of QCL-Type A, QCL-Type B, and QCL-Type C. In this case, the configurable QCL type depends on the types of the target antenna port and the reference antenna port, as described in detail below. Additionally, the second QCL configuration in a TCI state configuration can be configured as QCL-Type D, and may be omitted in some cases.

[0125] Tables 11 to 15 below show the valid TCI state configurations depending on the target antenna port type.

[0126] Table 11 shows the valid TCI state configuration when the target antenna port is a CSI-RS (TRS) for tracking. The TRS includes the unconfigured repeating parameter in the CSI-RS and “trs-Info” is configured as a true NZP CSI-RS. Configuration 3 in Table 11 can be used for aperiodic TRS.

[0127] Table 11 shows the valid TCI state configuration when the target antenna port is a CSI-RS (TRS) for tracking.

[0128] [Table 11]

[0129] Effective TCI state configuration when the target antenna port is a CSI-RS (TRS) for tracking.

[0130]

[0131] Table 12 shows the valid TCI state configuration when the target antenna port is a CSI-RS for CSI. A CSI-RS for CSI indicates an NZP CSI-RS where no duplicate parameters are configured in the CSI-RS and "trs-Info" is not configured as true.

[0132] [Table 12]

[0133] Valid TCI state configuration when the target antenna port is a CSI-RS for CSI.

[0134]

[0135] Table 13 shows the valid TCI status configuration when the target antenna port is a CSI-RS for beam management (BM) (with the same meaning as the CSI-RS for L1RSRP reporting). The CSI-RS for BM indicates that the CSI-RS is configured with a repeating parameter with an enabled or disabled value and "trs-Info" is not configured as a true NZP CSI-RS.

[0136] [Table 13]

[0137] Effective TCI state configuration when the target antenna port is for BM's CSI-RS

[0138] (For L1RSRP reporting)

[0139]

[0140] Table 14 shows the effective TCI state configuration when the target antenna port is PDCCH DMRS.

[0141] [Table 14]

[0142] Effective TCI state configuration when the target antenna port is PDCCH DMRS

[0143]

[0144] Table 15 shows the effective TCI state configuration when the target antenna port is PDSCH DMRS.

[0145] [Table 15]

[0146] Effective TCI state configuration when the target antenna port is PDSCH DMRS

[0147]

[0148] The typical QCL configuration methods in Tables 11 to 15 configure the target antenna port and reference antenna port for the corresponding operation as "SSB" → "TRS" → "CSI-RS for CSI, CSI-RS for BM, PDCCH DMRS, or PDSCH DMRS", and operate in the same manner. Thus, the statistical characteristics measurable from SSB and TRS can be associated with the corresponding antenna ports, thereby assisting the UE in performing reception operations.

[0149] Figure 5 This is a diagram illustrating the structure of the downlink control channel in a wireless communication system according to an embodiment of the present disclosure. That is, Figure 5 This is a diagram illustrating an example of the basic unit of time-frequency resources for a downlink control channel to be used in 5G, according to an embodiment.

[0150] refer to Figure 5 The basic unit of time-frequency resources constituting the control channel can be defined as a resource element group (REG) 503. REG 503 can be defined as one OFDM symbol 501 in the time domain and one physical resource block (PRB) 502 in the frequency domain, i.e., 12 subcarriers. The base station can configure the downlink control channel allocation unit by cascading REG 503.

[0151] like Figure 5 As shown, it is assumed that the basic unit for allocating downlink control channels in 5G is a Control Channel Element (CCE) 504, and one CCE 504 may include multiple REG 503s. For example, Figure 5 The REG 503 shown may include 12 REs. If one CCE 504 includes 6 REG 503s, then one CCE 504 may include 72 REs. If a downlink control resource set is configured, the corresponding area may include multiple CCE 504s, and a specific downlink control channel may be mapped to one or more CCE 504s according to the aggregation level (AL) in the control resource set, and then it may be transmitted. The CCE 504s in the control resource set are identified by labels, and the labels of the CCE 504s may be assigned according to a logical mapping method.

[0152] Figure 5The basic unit of the downlink control channel shown (i.e., REG 503) may include the region mapped to by the DCI and the region mapped to by DMRS 505, which is the reference signal used for decoding. Figure 5 As shown, three DMRS 505s can be transmitted within one REG 503. Depending on the aggregation level (AL), the number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16, and different numbers of CCEs can be used to implement link adaptation for the downlink control channel. For example, if AL = L, one downlink control channel can be transmitted through L CCEs.

[0153] The UE needs to detect signals without knowing information related to the downlink control channels and can define a search space to indicate a set of CCEs for blind decoding. The search space is a set of candidate downlink control channels that the UE must attempt to decode at a given aggregation level. Because there are various aggregation levels that bundle 1, 2, 4, 8, or 16 CCEs together, the UE can have multiple search spaces. The search space set can be defined as the set of search spaces across all configured aggregation levels.

[0154] The search space can be classified into a common search space and a UE-specific search space. According to the implementation, a specific group of UEs or all UEs can verify the common search space of the PDCCH to receive cell common control information, such as dynamic scheduling or paging messages for system information.

[0155] For example, a UE can receive PDSCH scheduling and allocation information for transmitting SIBs, including cell operator information, by verifying the common search space of the PDCCH. In the case of a common search space, since a specific UE group or all UEs must receive the PDCCH, the common search space can be defined as a set of predetermined CCEs. Simultaneously, a UE can receive scheduling and allocation information for a UE-specific PDSCH or PUSCH by verifying the UE-specific search space of the PDCCH. The UE-specific search space can be specifically defined by the UE as a function of the UE identifier and various system parameters.

[0156] In 5G, parameters in the search space used for PDCCH can be configured by the base station to the UE using upper-layer signaling (e.g., SIB, MIB, or RRC signaling). For example, the base station can configure for the UE the number of candidate PDCCHs in each aggregation level L, the monitoring period of the search space, the monitoring timing in symbols within the time slots of the search space, the search space type (common search space or UE-specific search space), the combination of DCI format and RNTI to be monitored in the search space, and the control resource set index for monitoring the search space, etc. For example, the above configuration may include the information shown in Table 16 below.

[0157] [Table 16]

[0158]

[0159]

[0160]

[0161] The base station can configure one or more search space sets for the UE based on configuration information. According to the implementation method, the base station can configure search space set 1 and search space set 2 for the UE. The base station can configure DCI format A scrambled by X-RNTI in search space set 1 for monitoring in a common search space, and can configure DCI format B scrambled by Y-RNTI in search space set 2 for monitoring in a UE-specific search space.

[0162] Depending on the configuration information, a public search space or a UE-specific search space may include one or more search space sets. For example, search space set #1 and search space set #2 may be configured as a public search space, and search space set #3 and search space set #4 may be configured as UE-specific search spaces.

[0163] Public search spaces can be categorized into specific types of search space sets based on their purpose. The RNTIs to be monitored can differ between the identified types of search space sets. For example, public search space types, purposes, and the RNTIs to be monitored can be categorized as shown in Table 17 below.

[0164] [Table 17]

[0165]

[0166]

[0167] Furthermore, combinations of the following DCI formats and RNTI can be monitored in the public search space. This disclosure is not limited to the following implementation methods.

[0168] -DCI format 0_0 / 1_0, with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI and Si-RNTI.

[0169] -DCI format 2_0, with CRC scrambled by SFI-RNTI

[0170] -DCI format 2_1, with CRC scrambled by INT-RNTI

[0171] -DCI format 2_2, with CRC scrambled by TPC-PUSCH-RNTI and TPC-PUCCH-RNTI.

[0172] -DCI format 2_3, with CRC scrambled by TPC-SRS-RNTI

[0173] Within a UE-specific search space, combinations of the following DCI formats and RNTI can be monitored. This disclosure is not limited to the following implementations.

[0174] -DCI format 0_0 / 1_0, with CRC scrambled by C-RNTI, CS-RNTI and TC-RNTI.

[0175] -DCI format 1_0 / 1_1, with CRC scrambled by C-RNTI, CS-RNTI and TC-RNTI.

[0176] A specific RNTI can be defined and used as follows.

[0177] Cell RNTI (C-RNTI) used for UE-specific PDSCH scheduling

[0178] Temporary Cell RNTI (TC-RNTI) used for UE-specific PDSCH scheduling

[0179] Scheduling RNTI (CS-RNTI) for UE-specific PDSCH scheduling in semi-static configuration

[0180] Random Access RNTI (RA-RNTI) used for PDSCH scheduling during the random access phase

[0181] Paging RNTI (P-RNTI) used for PDSCH scheduling to send paging requests

[0182] System Information RNTI (SI-RNTI) used for PDSCH scheduling to send system information

[0183] The interrupt RNTI (INT-RNTI) is used to notify PDSCH of puncturing.

[0184] Transmit power control (TPC-PUSCH-RNTI) of the PUSCH RNTI used to indicate power control commands for PUSCH.

[0185] Transmit power control (TPC-PUCCH-RNTI) used to indicate power control commands for the PUCCH.

[0186] Transmit power control (TPC-SRS-RNTI) of the SRS RNTI used to indicate power control commands of the SRS

[0187] In the implementation, the above DCI format can be defined as shown in Table 18 below.

[0188] [Table 18]

[0189]

[0190]

[0191] According to the implementation method, multiple search space sets can be configured using different parameters in 5G (e.g., the parameters in Table 10). Therefore, the set of search space sets monitored by the UE can be different each time. For example, if search space set #1 is configured for an X-slot period, if search space set #2 is configured for a Y-slot period, and if X and Y are different, the UE can monitor search space set #1 and search space set #2 in a specific time slot, and can monitor only one of search space set #1 and search space set #2 in a specific time slot.

[0192] If multiple search space sets are configured for the UE, the following conditions can be considered to determine the search space set that the UE should monitor.

[0193] [Condition 1: Limit the maximum number of candidate PDCCHs]

[0194] The number of candidate PDCCHs that can be monitored in each time slot cannot exceed M. μ M μ This can be defined as the subcarrier spacing being set to 15.2. μ The maximum number of PDCCH candidates per time slot in a cell of kHz, and can be defined as shown in Table 19 below.

[0195] [Table 19]

[0196]

[0197] [Condition 2: Limit the maximum number of CCEs]

[0198] The number of CCEs constituting the entire search space in each time slot cannot exceed C. μ (The entire search space can be represented as the set of all CCEs corresponding to the joint region of multiple search space sets). C μ This can be defined as the subcarrier spacing being set to 15.2. μ The maximum number of CCEs per time slot in a kHz cell, and can be defined as shown in Table 20 below.

[0199] [Table 20]

[0200]

[0201] For ease of explanation, the situation where conditions 1 and 2 are satisfied at a specific time can be defined as "condition A". Therefore, the situation where condition A is not satisfied can represent the situation where at least one of conditions 1 and 2 is not satisfied.

[0202] Depending on the configuration of the search space set of the base station, condition A may not be met at a specific time. If condition A is not met at a specific time, the UE may select and monitor only some of the search space sets configured to meet condition A at that time, and the base station may send PDCCH to the selected search space set.

[0203] According to the implementation method, some search spaces can be selected from the overall configuration search space set according to the following method.

[0204] [Method 1]

[0205] If PDCCH condition A is not met at a specific time (time slot), the UE (or base station) can preferentially select from the search space set that exists at the corresponding time, the search space type being configured as a common search space, rather than the search space set that is configured as a UE-specific search space.

[0206] If all search space sets configured as public search spaces are selected (i.e., even after selecting all search spaces configured as public search spaces if condition A is met), the UE (or base station) may select a search space set configured as a UE-specific search space. In this case, if multiple search space sets exist as UE-specific search spaces, the search space set with a lower search space set index may have higher priority. The UE or base station may select a UE-specific search space set within the range that satisfies condition A, taking priority into account.

[0207] The methods for allocating time-frequency resources for data transmission in NR will be described below.

[0208] In addition to allocating candidate frequency domain resources via BWP indication, NR also provides the following detailed frequency domain resource allocation (FD-RA) methods.

[0209] Figure 6 This is a diagram illustrating an example of frequency domain resource allocation for the Physical Downlink Shared Channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure.

[0210] Figure 6 This diagram illustrates three frequency domain resource allocation methods: Type 0 (6-00), Type 1 (6-05), and Dynamic Switching 6-10. These methods can be configured through the upper layers in NR.

[0211] refer to Figure 6When the UE is configured via upper-layer signaling to use only resource type 0 (6-00), some downlink control information (DCI) used to allocate PDSCH to the UE has a bitmap with NRBG bits. The conditions for this situation will be described later. In this case, NRBG represents the number of resource block groups (RBGs) determined by the size of the BWP allocated by the BWP indicator and the upper-layer parameter "rbg-Size", as shown in Table 21 below, and the data is transmitted in RBGs represented by bitmap "1".

[0212] [Table 21]

[0213] Bandwidth portion size Configuration 1 Configuration 2 1-36 2 4 37-72 4 8 73-144 8 16 145-275 16 16

[0214] When the UE is configured to use only resource type 1 (6-05) via upper-layer signaling, some DCIs used to allocate PDSCH to the UE have the following features: This involves the allocation of frequency domain resources. The conditions for this configuration will be described again later. The base station can be configured with an initial VRB of 6-20 and subsequent frequency domain resource lengths of 6-24.

[0215] If the UE is configured via upper-layer signaling to use both resource type 0 and resource type 1 (6-10), then some DCIs used to allocate PDSCH to the corresponding UE have frequency domain resource allocation information, which includes the larger of the two bits (6-15) for configuring resource type 0 and 6-20 and 6-25 for configuring resource type 1. The conditions for this scenario will be described again later. In this case, a bit (6-30) can be added to the first part (MSB) of the frequency domain resource allocation information in the DCI; a bit of 0 indicates the use of resource type 0, and a bit of 1 indicates the use of resource type 1.

[0216] The following section describes a method for allocating time-domain resources for data channels in next-generation mobile communication systems (5G or NR systems).

[0217] The base station can configure tables for the UE regarding time-domain resource allocation information for downlink data channels (Physical Downlink Shared Channel (PDSCH)) and uplink data channels (Physical Uplink Shared Channel (PUSCH)) via upper-layer signaling (e.g., RRC signaling). Tables with up to maxNrofDL-Allocation = 16 entries can be configured for the PDSCH, and tables with up to maxNrofUL-Allocation = 16 entries can be configured for the PUSCH. In the implementation, the time-domain resource allocation information may include the time slot timing from PDCCH to PDSCH (corresponding to the time interval between the time of receiving PDCCH and the time of sending PDSCH scheduled by the received PDCCH, denoted as K0), the time slot timing from PDCCH to PUSCH (corresponding to the time interval between the time of receiving PDCCH and the time of sending PUSCH scheduled by the received PDCCH, denoted as K2), information related to the position and length of the start symbol of the PDSCH or PUSCH scheduled in the time slot, the mapping type of PDSCH or PUSCH, etc. For example, the information shown in Table 22 or Table 23 below can be notified to the UE from the base station.

[0218] [Table 22]

[0219]

[0220] [Table 23]

[0221]

[0222] The base station can notify the UE of one of the entries in the table used for the aforementioned time-domain resource allocation information via L1 signaling (e.g., DCI). (For example, it may be indicated by the "Time-domain Resource Allocation" field in the DCI). The UE can obtain the time-domain resource allocation information for PDSCH or PUSCH based on the DCI received from the base station.

[0223] Figure 7 This is a diagram illustrating an example of allocating time-domain resources of a PDSCH in a wireless communication system according to an embodiment of the present disclosure.

[0224] refer to Figure 7 The base station can determine the subcarrier spacing (SCS) (μ) of the data and control channels configured by the upper layer. PDSCH and μ PDCCH The scheduling offset (K0), the start position 7-00 of the OFDM symbol within a time slot 7-10 dynamically indicated by DCI, and its length 7-05 are configured to indicate the temporal location of the PDSCH resource.

[0225] Figure 8 This is a diagram illustrating an example of allocating time-domain resources in a wireless communication system according to the subcarrier spacing of the data channel and the control channel, according to an embodiment of the present disclosure.

[0226] refer to Figure 8 If the subcarrier spacing of the data channel is different from that of the control channel (μ PDSCH =μ PDCCH If the subcarrier spacing of the data channel is the same (8-00), then the time slot number used for data and the time slot number used for control are the same. Therefore, the base station and the UE can identify scheduling offsets based on the predetermined time slot offset (K0). On the other hand, if the subcarrier spacing of the data channel is different from that of the control channel (μ...), then... PDSCH ≠μ PDCCH The subcarrier spacing (8-05) of the PDCCH means that the time slot number used for data and the time slot number used for control are different from each other. Therefore, the base station and the UE can identify the scheduling offset based on the subcarrier spacing of the PDCCH and according to the predetermined time slot offset (K0).

[0227] Next, a beam configuration method for the base station to transmit control information and data to the UE will be described. In this disclosure, for ease of explanation, the process of transmitting control information via PDCCH can be described as "transmitting PDCCH", and the process of transmitting data via PDSCH can be described as "transmitting PDSCH".

[0228] Figure 9 This is a diagram illustrating an example of an antenna port configuration for cooperative communication according to an embodiment of the present disclosure.

[0229] First, the beam configuration method for PDCCH will be described. (Reference) Figure 9 This illustrates the process of configuring and activating the PDCCH beam. First, the TCI state list for each CORESET can be indicated by a higher-level list such as RRC (9-00). The TCI state list can be indicated by “tci-StatesPDCCH-ToAddList” and / or “tci-StatesPDCCH-ToReleaseList” in Table 8. Next, one of the TCI states in the list configured for each CORESET can be activated via MAC-CE (9-20). Figure 9-50 shows an example of the MAC-CE structure used to activate the TCI state of the PDCCH. The definition of each field in the MAC-CE and the available values ​​for each field are as follows.

[0230]

[0231] Figure 10 This is a diagram illustrating the process of configuring and activating the PDSCH beam according to an embodiment of this disclosure.

[0232] Next, the beam configuration method for PDSCH will be described. (Reference) Figure 10 The diagram illustrates the process of configuring and activating the PDSCH beam. The PDSCH TCI state list can be indicated by a higher-level list such as RRC (10-00). The TCI state list can be indicated by, for example, “tci-StatesToAddModList” and / or “tci-StatesToReleaseList” in the PDSCH configuration IE for each BWP. Next, some TCI states in the list can be activated via MAC-CE (10-20). The maximum number of active TCI states can be determined based on the UE reporting capability. Figure 10-50 shows an example of the MAC-CE structure for activating / disabling PDSCH TCI states based on Rel-15.

[0233] The definitions and available values ​​for each field in MAC CE are as follows.

[0234]

[0235] When the UE receives DCI format 1_1 or DCI format 1_2, the PDSCH can be received by a beam in the TCI state activated via MAC-CE based on the information in the Transmission Configuration Indication (TCI) field of the DCI (10-40). The presence or absence of the TCI field can be determined by the value "tci-PresentinDCI", which is an upper-layer parameter configured in the CORESET for receiving the DCI. If "tci-PresentinDCI" is configured to be "enabled" in the upper layer, the UE can identify the TCI field with 3 bits of information to determine the direction of the beam associated with the TCI state activated in the DL BWP, or the scheduled component carrier and DL-RS.

[0236] In LTE and NR, upon connecting to a base station, the UE performs a process of reporting UE-supported capabilities to the serving base station. In the following description, the UE-supported capability report will be referred to as a "UE capability (report)". The base station may send a UE capability query message requesting a capability report to the UE in a connected state. This message may include the base station's request for UE capabilities for each RAT type. The request for each RAT type may include information related to the requested frequency band. Furthermore, the UE capability query message may be sent simultaneously requesting multiple RAT types through a single RRC message container, or it may include multiple UE capability query messages including requests for the corresponding RAT types, which can then be sent to the UE. That is, UE capability queries can be repeated multiple times, and the UE can configure its corresponding UE capability information message and report it multiple times. In next-generation mobile communication systems, requests for UE capabilities can be performed for MR-DC as well as NR, LTE, and EN-DC. For reference, UE capability query messages are typically sent in the initial phase after UE connection, but the base station can request UE capabilities under any conditions as needed.

[0237] In the above operations, the UE that receives the UE capability request from the base station configures its capabilities based on the RAT type and frequency band information requested by the base station. The following outlines the method for configuring UE capabilities by the UE in an NR system.

[0238] 1. If the UE receives a list of LTE and / or NR frequency bands via a UE capability request from the base station, the UE configures a band combination (BC) for EN-DC and NR Independent (SA). That is, the UE configures a candidate BC list for EN-DC and NR SA based on the frequency bands requested by the base station using the "FreqBandList". Furthermore, these frequency bands have the priority order described in the "FreqBandList".

[0239] 2. If the base station requests a UE capability report by setting the “eutra-nr-only” flag or the “eutra” flag, the UE completely removes NR SA BCs from the configured candidate BC list. This operation can only be performed when the LTE base station (eNB) requests “eutra” capability.

[0240] 3. Subsequently, the UE removes the fallback BC from the candidate BC list configured in the above operation. A fallback BC corresponds to the removal of the frequency band corresponding to at least one SCell from a superset of BCs. Since the superset of BCs can cover the fallback BC, it can be omitted. This operation also applies to MR-DC, i.e., LTE frequency bands. The remaining BCs after this operation constitute the final "candidate BC list".

[0241] 4. The UE selects the BCs that conform to the requested RAT type from the final "Candidate BC List". In this operation, the UE configures the "supportedBandCombinationList" in a predetermined order. That is, the UE configures the BCs to be reported and the UE capability reports in a predetermined order (nr→eutra-nr→eutra). In addition, the UE configures the "featureSetCombination" for the configured "supportedBandCombinationList", and configures the "candidate feature set combinations" list from the candidate BC list, removing the fallback BCs (including capabilities of equal or lower level) from the candidate BC list. The "candidate feature set combination" can include feature set combinations of BCs for both NR and EUTRA-NR, and can be obtained from the feature set combinations in the "UE-NR-Capabilities" and "UE-MRDC-Capabilities" containers.

[0242] 5. Additionally, if the requested RAT type is “eutra-nr” and is valid, then “featuresSetCombinations” are included in both the “UE-MRDC-Capabilities” and “UE-NR-Capabilities” containers. However, the NR feature set is only included in “UE-NR-Capabilities”.

[0243] After configuring UE capabilities, the UE sends a UE capability information message, including the UE capabilities, to the base station. Then, the base station performs appropriate scheduling and transmit / receive management on the UE based on the UE capabilities received from the UE.

[0244] Figure 11 This is a diagram illustrating the radio protocol structure of a base station and a UE in single-cell, carrier aggregation, and dual-connectivity scenarios according to embodiments of the present disclosure.

[0245] refer to Figure 11 The radio protocols of the next-generation mobile communication system include the NR Service Data Adaptation Protocol (SDAP) layer S25 or S70, the NR Packet Data Convergence Protocol (PDCP) layer S30 or S65, the NR Radio Link Control (RLC) layer S35 or S60, and the NR Media Access Control (MAC) layer S40 or S55 in the UE and NR base station.

[0246] The main functions of NR SDAP S25 or S70 may include some of the following functions.

[0247] User plane data transmission

[0248] - Mapping between QoS flows and DRB for both DL and UL

[0249] -Tag QoS flow IDs in DL and UL packets

[0250] -Mapping of reflected QoS flow from UL SDAP PDU to DRB

[0251] Regarding SDAP layer entities, the UE can receive indications via RRC messages regarding whether to use the SDAP layer entity header or whether to use the SDAP layer entity functionality configuration for each PDCP layer entity, each bearer, or each logical channel. When the SDAP header is configured, the 1-bit NAS reflection QoS configuration indicator and the 1-bit AS reflection QoS configuration indicator in the SDAP header can instruct the UE to update or reconfigure the mapping information between QoS flows and data bearers in the uplink and downlink. The SDAP header may include QoS flow ID information indicating QoS. QoS information can be used for data processing priority, scheduling information, etc., to support effective service.

[0252] The main functions of NR PDCP S30 or S65 may include some of the following functions.

[0253] - Header compression and decompression (ROHC only)

[0254] -User data transmission

[0255] - Sequential transmission of upper-layer PDUs

[0256] -Disordered transmission of upper-layer PDUs

[0257] - Sequence rearrangement (for receiving PDCP PDU rearrangement)

[0258] -Duplicate detection of lower-level SDUs

[0259] -PDCP SDU retransmission

[0260] - Encryption and decryption

[0261] - Timer-based SDU dropping in the uplink

[0262] The reordering function of the NR PDCP layer entity represents the function of reordering PDCP PDUs received from the lower layer based on the PDCP sequence number (SN). It may include the function of sending data to the upper layer in the reordered order, the function of sending data directly without considering the order, the function of reordering and recording lost PDCP PDUs, the function of sending a status report of lost PDCP PDUs to the sender, and the function of requesting retransmission of lost PDCP PDUs.

[0263] The main functions of NR RLC S35 or S60 may include some of the following functions.

[0264] - Data transmission function (transmission of upper-layer PDUs)

[0265] - Sequential transmission of upper-layer PDUs

[0266] -Disordered transmission of upper-layer PDUs

[0267] -ARQ functionality (error correction via ARQ)

[0268] Cascading, segmentation, and reassembly of RLC SDUs

[0269] - RLC data PDU resegmentation

[0270] -RLC data PDU rearrangement

[0271] -Duplicate detection

[0272] -Protocol error detection

[0273] -RLC SDU discard

[0274] -RLC Reconstruction

[0275] The sequential transmission function of the NR RLC layer entity represents the function of sequentially transmitting RLC SDUs received from the lower layer to the upper layer. This may include the function of reassembling and transmitting an original RLC SDU that has been divided into multiple RLC SDUs and received; the function of rearranging received RLC PDUs based on the RLC sequence number (SN) or PDCP sequence number (SN); the function of rearranging the order and recording lost RLC PDUs; the function of sending a report of lost RLC PDUs to the sender; the function of requesting retransmission of lost RLC PDUs; the function of sequentially transmitting only RLC SDUs preceding the lost RLC SDU to the upper layer if a lost RLC SDU exists; the function of sequentially transmitting all RLC SDUs received before the start of a timer if a timer expires, even if a lost RLC SDU exists; or the function of sequentially transmitting all RLC SDUs received up to the current timer to the upper layer if a timer expires, even if a lost RLC SDU exists. RLC PDUs can be processed in the order of reception (according to arrival order, regardless of sequence number or its sequence number) and can be sent to the PDCP layer entity out of order. In the case of fragmentation, segments stored in a buffer or subsequently received can be received and reconfigured into a complete RLC PDU, which can then be processed and sent to the PDCP layer entity. The NR RLC layer may not include cascading functionality, which can be performed in the NR MAC layer or replaced by multiplexing functionality of the NR MAC layer.

[0276] The out-of-order transmission of NR RLC layer entities refers to the function of sending RLC SDUs received from the lower layer directly to the upper layer regardless of the order. It may include the function of reassembling and sending an original RLC SDU if it is divided into multiple RLC SDUs and received. It may also include the function of storing and sorting the RLC SN or PDCP SN of the received RLC PDUs to record lost RLC PDUs.

[0277] The NR MAC S40 or S55 can connect to multiple NR RLC layer entities configured in a single UE, and the main functions of the NR MAC may include some of the following functions.

[0278] - Mapping between logical channels and transmission channels

[0279] - MAC SDU multiplexing / demultiplexing

[0280] - Scheduling Information Report

[0281] - HARQ functionality (error correction via HARQ)

[0282] Priority processing between logical channels of a UE

[0283] Priority handling among dynamically scheduled UEs

[0284] -MBMS service identification

[0285] -Transmission format selection

[0286] -filling

[0287] The NR PHY layer 1d-20 or 1d-25 can encode and modulate the upper layer data channel into OFDM symbols, and transmit the OFDM symbols via a wireless channel; or demodulate and decode the OFDM symbols received via a wireless channel, and transmit the OFDM symbols to the upper layer.

[0288] The NR PHY layers S45 and S50 can perform channel coding and modulation into OFDM symbols on upper-layer data and transmit them via radio channels, or perform demodulation and channel decoding on OFDM symbols received via radio channels and transmit them to the upper layer.

[0289] The detailed structure of a radio protocol can be varied depending on the carrier (or cell) operation scheme. For example, when the base station transmits data to the UE based on a single carrier (or cell), the base station and the UE use a single protocol structure for each layer, as shown in S00. On the other hand, when 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 use a protocol structure that provides a single structure up to the RLC layer and multiplexes the PHY layer through the MAC layer, as shown in S10. As another example, when 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 use a protocol structure that provides a single structure up to the RLC layer and multiplexes the PHY layer through the MAC layer, as shown in S20.

[0290] Meanwhile, if the interval between the end symbol of PDCCH transmission and the start symbol of PDSCH scheduled by PDCCH is less than a specific threshold, the UE may not have completed PDCCH decoding when receiving PDSCH. This means that the beam information for PDSCH reception indicated by the DCI of PDCCH cannot be received. In this case, the base station and the UE can specify a default beam for PDSCH reception. That is, in the above case, the base station uses the specified default beam to transmit PDSCH, and the UE can use the specified default beam to perform buffering. If the UE determines after PDCCH decoding that there is a PDSCH scheduled before PDCCH decoding, it can perform PDSCH decoding from the buffered signal according to the default beam. In this case, the aforementioned threshold can be the value "TimeDurationForQCL" reported as the UE capability report. Furthermore, the aforementioned default beam operation can be limited to situations where one or more TCI states in the TCI state list 10-00 configured for PDSCH include "QCL-TypeD", i.e., the UE reception beam is configured. In this scenario, the default beam can be a beam configured based on the PDSCH receive time slot, within the CORESET corresponding to the lowest ID (e.g., CORESET#0) of the CORESET corresponding to the search space monitored in the most recent time slot. In other words, the default beam can be a beam configured using the PDSCH receive time slot as a reference point, within the CORESET corresponding to the lowest ID (e.g., CORESET#0) of the CORESET corresponding to the search space monitored in the most recent time slot.

[0291] The default beaming operation for receiving PDSCH can be limited to cases where cross-carrier configuration is not set for PDSCH.

[0292] Figure 12 This is a diagram illustrating an example of PDSCH default beam operation according to an embodiment of this disclosure.

[0293] refer to Figure 12 This illustrates an example of PDSCH default beaming operation. If the TCI field for receiving PDSCH in DCI 12-00 transmitted via PDCCH indicates TCI status #n (12-10), then default beaming 12-60 can be applied to PDSCH if the interval between the end symbol of the PDCCH transmission and the start symbol of PDSCH 12-40 scheduled by PDCCH is less than “timeDurationforQCL” 12-20, and if one or more TCI statuses in the TCI status list for PDSCH configured via RRC include “QCL-TypeD”.

[0294] Meanwhile, if the parameter "tci-PresentinDCI" is not configured in the CORESET, or if the PDSCH is scheduled in DCI format 1_0, the UE cannot use DCI to receive the beam indication for PDSCH reception because there is no TCI field in the DCI. In this case, if the interval between the end symbol of the PDCCH transmission and the start symbol of the PDSCH scheduled by the PDCCH is greater than or equal to the value "timeDurationForQCL", the UE can assume that the beam used to receive the PDSCH is the same as the beam configured / activated in the PDCCH transmission CORESET, and the base station can configure the PDSCH transmission beam according to the UE's assumption. The default beam operation for receiving PDSCH can be limited to the case where no cross-carrier configuration is configured for the PDSCH.

[0295] Next, the configuration for cross-carrier scheduling for PDSCH will be described. For cross-carrier scheduling, the configuration parameters configured for each serving cell / component carrier (CC) via RRC (i.e., “CrossCarrierSchedulingConfig” with the following structure) can be configured in the parameter “ServingCellConfig IE” configured for each serving cell / component carrier (CC).

[0296]

[0297] In the case of cross-carrier scheduling from a specific serving cell to another serving cell, for convenience, the specific serving cell can be referred to as the "scheduling cell," and the "cif-Presence" value in the parameter "crossCarrierSchedulingConfig" can be configured to true. In this case, the Carrier Indicator field (CIF) described in Table 4 can exist in the DCI format 0_1 ​​or 1_1 of the scheduling cell. If the CIF indication value is 0, the PDSCH scheduled in DCI format is transmitted through the scheduling cell. On the other hand, if the CIF indication value is non-zero, the PDSCH scheduled in DCI format is transmitted through a serving cell other than the scheduling cell. For convenience, the serving cell corresponding to the CIF value can be referred to as the "scheduled cell," and the mapping between a specific scheduled cell and the CIF value can be performed by the value "cif-InSchedulingCell" in the "other" field of the parameter "crossCarrierSchedulingConfig." In other words, if the value "cif-InSchedulingCell" is configured in the "ServingCellConfig" of a specific scheduled cell, the UE can be instructed to send PDSCH through that scheduled cell by configuring the CIF value in the DCI of the scheduling cell to the value "cif-InSchedulingCell". For a specific scheduled cell, there can be only one scheduling cell, and the scheduling cell indication for that specific scheduled cell can be performed by specifying the "schedulingCellId" value in the "other" field of the parameter "crossCarrierSchedulingConfig" used for scheduling the cell as the ID of the scheduling cell.

[0298] Additionally, for cross-carrier scheduling configurations, it may be necessary to configure a search space set with the same ID between the active BWP of the scheduling cell and the active BWP of the scheduled cell.

[0299] If cross-carrier scheduling is configured in a specific serving cell as described above, the CIF value in the DCI field of the scheduling cell can be used to identify whether the scheduling cell and the scheduled cell belong to the same serving cell. Meanwhile, if the scheduling cell is different from the scheduled cell, CORESET may not be configured in the scheduled cell. In this case, the PDSCH default beam may be unclear in the following situations: (i) the interval between the last symbol of the PDCCH in the scheduling cell and the start symbol of the scheduled PDSCH is less than "timeDurationforQCL"12-20; or (ii) "tci-PresentinDCI" is not configured in the DCI used for scheduling the PDSCH. If the base station and UE have different assumptions about the PDSCH default beam when configuring cross-carrier scheduling, there may be a problem where the UE cannot receive the PDSCH normally. Therefore, this disclosure provides a method for configuring the PDSCH default beam when cross-carrier scheduling is configured.

[0300] <First implementation: If cross-carrier scheduling is configured, the PDSCH default beam is not allowed>

[0301] When cross-carrier scheduling is configured, the UE may not expect a default PDSCH beam to be configured in the following situations: (i) the interval (offset) between the last symbol of the PDCCH in the scheduling cell and the starting symbol of the scheduled PDSCH is less than "timeDurationforQCL" 12-20; or (ii) "tci-PresentingDCI" is not configured in the DCI used for PDSCH scheduling. Alternatively, the base station can schedule the PDSCH according to the UE's operation to avoid these situations.

[0302] The operations of the UE and base station can be applied to all CIF values ​​in the DCI format used for PDSCH scheduling. That is, the operations of the UE and base station can be applied not only when the scheduling cell and the scheduled cell are the same, but also when the scheduling cell and the cell to be scheduled are different. This is likely due to the fact that since it is only after the PDCCH is decoded that it can be determined whether the CIF value in the DCI format is 0 (same scheduling cell and scheduled cell) or non-zero (different scheduling cell and scheduled cell), it is difficult to apply the PDSCH default beam differently based on the CIF value.

[0303] Figure 13 The operation of a base station and a UE according to a first embodiment of this disclosure is shown.

[0304] refer to Figure 13When cross-carrier scheduling is not configured as shown in Figure 13-00, PDSCH default beam operation is allowed; however, when cross-carrier scheduling is configured as shown in Figure 13-50, PDSCH default beam operation is not allowed regardless of the conditions shown in Figure 13-60 (i.e., CIF value).

[0305] The operation of the UE and the base station may be restricted to specific conditions. For example, in cases where it is not permitted in scenario (ii), it may be limited to PDSCHs scheduled in a specific DCI format (e.g., DCI format 1_1 and DCI format 1_2). In the case of a PDSCH scheduled in DCI format 1_0, since the CIF and TCI fields are not included in the DCI format, the beam configured in the CORESET of the PDCCH scheduled by the PDSCH can be used as the default beam of the PDSCH.

[0306] <Second Implementation: If cross-carrier scheduling is configured, then for CIF values ​​≠ 0, the PDSCH default beam is allowed.>

[0307] When cross-carrier scheduling is configured, a default PDSCH beam can be configured for cases where the CIF value in the scheduling DCI is not equal to 0 (i.e., the scheduling cell is different from the scheduled cell). In this case, since the scheduled cell may not have a CORESET configured, the UE will expect a default PDSCH beam for each of the following situations.

[0308] In case (i), the interval (offset) between the last symbol of the PDCCH and the starting symbol of the scheduled PDSCH in the scheduling cell is less than "timeDurationforQCL" (12-20).

[0309] It is assumed that the TCI state with the lowest TCI state ID in the PDSCH TCI state activated by MAC-CE is the default beam of the PDSCH. In other words, the TCI state with the lowest TCI state ID applicable to the PDSCH in the active BWP of the scheduled cell is the default beam of the PDSCH. The meaning of the TCI state being the default beam implies that the UE obtains the aforementioned QCL assumption of the PDSCH scheduled by the DCI based on the TCI state.

[0310] Case (ii) is that “tci-PresentinDCI” is not configured in the DCI used to schedule PDSCH.

[0311] It is assumed that the TCI state with the lowest TCI state ID in the PDSCH TCI state activated by MAC-CE is the default beam of the PDSCH. In other words, the TCI state with the lowest TCI state ID applicable to the PDSCH in the active BWP of the scheduled cell is the default beam of the PDSCH. The meaning of the TCI state being the default beam implies that the UE obtains the aforementioned QCL assumption of the PDSCH scheduled by the DCI based on the TCI state.

[0312] In addition, when the UE uses the default PDSCH beam, the base station can transmit the PDSCH based on the UE's assumption about the default PDSCH beam.

[0313] The operations of the UE and base station can be applied to specific CIF values ​​in the DCI format defined for PDSCH scheduling. For example, the operations of the UE and base station may only be applied if the CIF value is not 0 (if the scheduling cell is different from the scheduled cell), and may not be applied if the CIF value is 0 (if the scheduling cell is the same as the scheduling cell). This is because the aforementioned assumption of the UE for the PDSCH default beam may be suitable for cases where there is no CORESET in the scheduled cell. If the CIF value is 0, according to the first implementation, the UE may not expect the PDSCH default beam to be configured, and the base station may schedule the PDSCH to avoid the case where the default beam is configured.

[0314] Figure 14 This is a diagram illustrating the operation of a base station and user equipment according to embodiments of the present disclosure.

[0315] refer to Figure 14 The diagram illustrates the operation of the base station and UE according to the second embodiment. When cross-carrier scheduling is not configured as shown in Figure 14-00, PDSCH default beam operation is allowed; however, when cross-carrier scheduling is configured as shown in Figure 14-50, the following conditions (i.e., CIF value) apply according to Figure 14-60: if the CIF value is not 0 (if the scheduling cell and the scheduled cell are different), PDSCH default beam operation is allowed; if the CIF value is 0, PDSCH default beam operation is not allowed (if the scheduling cell and the scheduled cell are the same).

[0316] <Third implementation: If cross-carrier scheduling is configured, the PDSCH default beam is allowed according to the CIF value>.

[0317] When cross-carrier scheduling is configured, if the PDSCH default beam is not allowed according to the first embodiment, the symbol interval (offset) between the PDCCH and the scheduled PDSCH must always be greater than or equal to a specific value, which will result in a longer PDSCH transmission delay. Furthermore, in some cases (e.g., when the UE is indoors and does not move), dynamic beam changes for the PDSCH are not required, but if the PDSCH default beam is not allowed in this case, unnecessary configuration and control information transmission overhead for each PDSCH indication beam may occur. Additionally, according to the second embodiment, when cross-carrier scheduling is configured, if the PDSCH default beam is allowed only when the CIF value ≠ 0, this may introduce unnecessary restrictions, i.e., the PDSCH default beam is not allowed when the scheduling cell and the scheduled cell are the same (i.e., CIF value = 0). Therefore, it is required that the PDSCH default beam is allowed for all CIF values, and different PDSCH default beams need to be configured for the cases where the CIF value = 0 and the CIF value ≠ 0.

[0318] First, if the CIF value is not equal to 0, then the PDSCH default beam can be allowed according to the second implementation method.

[0319] On the other hand, if the CIF value is 0 (i.e., if the scheduling cell and the scheduled cell are the same), then CORESET can be configured in the scheduled cell. Therefore, in each of the following cases, the UE can expect the PDSCH default beam to be one of the following.

[0320] In case (i), the interval (offset) between the last symbol of the PDCCH in the scheduled cell and the starting symbol of the scheduled PDSCH is less than "timeDurationforQCL" (12-20).

[0321] Method i-1. It is assumed that the TCI state configured in the CORESET corresponding to the lowest ID (e.g., CORESET#0) in the CORESET corresponding to the search space monitored in the most recent slot based on the PDSCH receive time slot is the default beam of PDSCH.

[0322] Using the PDSCH receive time slot as a reference point, assuming that the TCI state configured in the CORESET corresponding to the lowest ID in the CORESET corresponding to the search space detected in the most recent time slot is the default beam of the PDSCH, the UE monitors the CORESET within the active BWP of the scheduling cell in that most recent time slot. Based on the above description, the TCI state can correspond to or be associated with one of the QCL parameters indicated by the PDCCHQCL for the CORESET.

[0323] The above method ensures consistency in UE operation with and without cross-carrier scheduling configured. In scenario (i) above, if different PDSCH default beams are configured based on whether cross-carrier scheduling is configured, the UE must perform different buffering operations depending on whether cross-carrier scheduling is configured, which makes UE implementation very complex.

[0324] Method i-2. It is assumed that the TCI state with the lowest TCI state ID in the PDSCH TCI states activated by MAC-CE is the default beam of the PDSCH.

[0325] The above method ensures consistency of UE operation across all CIF values ​​when cross-carrier scheduling is configured. In scenario (i) above, if different PDSCH default beams are configured based on whether the CIF value is 0, the UE must perform different buffering operations for each serving cell, which complicates the UE implementation.

[0326] Case (ii) is that “tci-PresentinDCI” is not configured in the DCI used to schedule PDSCH.

[0327] Method ii-1. It is assumed that the TCI state activated in the CORESET of the PDCCH used to schedule the PDSCH is the default beam of the PDSCH.

[0328] The above method ensures consistent UE operation with and without cross-carrier scheduling configured. Furthermore, since the method involves the PDSCH default beam applicable to DCI format 1_0, it ensures consistent UE operation across different DCI formats (e.g., DCI format 1_0, DCI format 1_1, and DCI format 1_2).

[0329] Method ii-2. It is assumed that the TCI state with the lowest TCI state ID in the PDSCH TCI state activated by MAC-CE is the default beam of PDSCH.

[0330] The above method ensures consistency of UE operation for all CIF values ​​when cross-carrier scheduling is configured.

[0331] In addition, when the UE uses the default PDSCH beam, the base station can transmit the PDSCH based on the UE's assumption about the default PDSCH beam.

[0332] Figure 15 This is a diagram illustrating the operation of a condition-based base station and user equipment according to an embodiment of the present disclosure.

[0333] Conditions for operation in the third embodiment described above can be configured. (See reference...) Figure 15 This is an example of the conditions for operation under the third embodiment. For example, to ensure backward compatibility of existing UEs, a UE operating based on Rel-15 can operate according to the first embodiment, while a UE operating based on Rel-16 can operate according to the third embodiment (15-00). Alternatively, a UE operating according to the third embodiment and a UE operating according to the first and second embodiments can be distinguished by UE capabilities. For example, a UE operating according to the first embodiment and a UE operating according to the second embodiment can be distinguished by releasing the UE, such that, for example, a Rel-15 UE can operate according to the first embodiment, and a Rel-16 UE can operate according to the second embodiment. A UE operating according to the second embodiment and a UE operating according to the third embodiment can be distinguished by capabilities that the UE further reports. For example, a Rel-16 UE that supports a specific capability can operate according to the third embodiment, while a UE that does not support that capability can operate according to the second embodiment (15-50).

[0334] Figure 16 This is a block diagram illustrating the structure of a UE in a wireless communication system according to an embodiment of the present disclosure.

[0335] refer to Figure 16 The UE may include a UE receiver 16-00, a UE transmitter 16-10, and a UE processor (controller) 16-05.

[0336] The UE receiver 16-00 and UE transmitter 16-10 can be collectively referred to as a "transceiver". The UE receiver 16-00, UE transmitter 16-10, and UE processor 16-05 in the UE can operate according to the communication method of the UE described above. However, the components of the UE are not limited to the examples above. For example, the UE may include more components (e.g., memory, etc.) or fewer components than those described above. Furthermore, the UE receiver 16-00, UE transmitter 16-10, and UE processor 16-05 can be implemented as a single chip.

[0337] The UE receiver 16-00 and UE transmitter 16-10 (or transceiver) can transmit signals to and receive signals from the base station. These signals may include control information and data. For this purpose, the transceiver may include an RF transmitter that up-converts and amplifies the signal to be transmitted, and an RF receiver that amplifies and down-converts the received signal with low noise. However, this is merely one implementation of the transceiver, and the components of the transceiver are not limited to RF transmitters and RF receivers.

[0338] In addition, the transceiver can receive signals via a radio channel, output them to the UE processor 16-05, and transmit signals output from the UE processor 16-05 via a radio channel.

[0339] The memory (not shown) may store programs and data required for UE operation. Additionally, the memory may store control information or data included in signals received by the UE. The memory may include storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or combinations thereof.

[0340] The UE processor 16-05 can control a series of processes, enabling the UE to operate according to the above-described implementation. The UE processor 16-05 can be implemented as a controller or one or more processors.

[0341] Figure 17 This is a block diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0342] refer to Figure 17 The base station may include a base station receiver 17-00, a base station transmitter 17-10, and a base station processor (controller) 17-05.

[0343] The base station receiver 17-00 and the base station transmitter 17-10 can be collectively referred to as a "transceiver". The base station receiver 17-00, base station transmitter 17-10, and base station processor 17-05 in the base station can operate according to the communication method of the base station described above. However, the components of the base station are not limited to the examples described above. For example, the base station may include more components (e.g., memory, etc.) or fewer components than described above. Furthermore, the base station receiver 17-00, base station transmitter 17-10, and base station processor 17-05 may be implemented as a single chip.

[0344] The base station receiver 17-00 and the base station transmitter 17-10 (or transceiver) can transmit signals to and receive signals from the UE. These signals may include control information and data. For this purpose, the transceiver may include an RF transmitter that up-converts and amplifies the signal to be transmitted, and an RF receiver that amplifies and down-converts the received signal with low noise. However, this is merely one implementation of the transceiver, and the components of the transceiver are not limited to RF transmitters and RF receivers.

[0345] In addition, the transceiver can receive signals via a radio channel, output them to the base station processor 17-05, and transmit signals output from the base station processor 17-05 via a radio channel.

[0346] A memory (not shown) may store programs and data required for base station operation. Additionally, the memory may store control information or data included in signals acquired by the base station. The memory may include storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or combinations thereof.

[0347] The base station processor 17-05 can control a series of processes, enabling the base station to operate according to the above-described embodiments. The base station processor 17-05 can be implemented as a controller or one or more processors.

[0348] In the accompanying drawings describing the methods of this disclosure, the order of description does not always correspond to the order in which the operations of each method are performed; the order of these operations may be changed or these operations may be performed in parallel.

[0349] Optionally, in the accompanying drawings describing the methods of this disclosure, some elements may be omitted and only some elements may be included without departing from the basic spirit and scope of this disclosure.

[0350] Furthermore, in the methods disclosed herein, some or all of the elements of each embodiment may be combined without departing from the basic spirit and scope of this disclosure.

[0351] Additionally, although not disclosed in this disclosure, the method may also use information from a separate table or including at least one item from the table presented in this disclosure.

[0352] Although this disclosure has been described with reference to various embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of this disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receive cross-carrier scheduling configuration from the base station, the cross-carrier scheduling configuration including information indicating that the carrier indicator field CIF is included in the downlink control information DCI; On the Physical Downlink Control Channel (PDCCH), the DCI for scheduling the Physical Downlink Shared Channel (PDSCH) is received from the scheduling cell of the base station, the DCI including the CIF; If the CIF indicates that the PDSCH resource is allocated to the scheduled cell, identify whether a first offset value between the reception of the PDCCH and the reception of the PDSCH is less than a threshold. as well as If the first offset value is less than the threshold and the terminal supports default beam selection for the PDSCH, data on the PDSCH is received from the scheduling cell of the base station based on the quasi-parameter QCL parameter of the control resource set CORESET associated with the search space having the lowest CORESET identifier ID within the active bandwidth portion BWP of the scheduling cell in the most recent time slot as monitored by the terminal.

2. The method according to claim 1, further comprising: If the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, identify whether the second offset value between the reception of the PDCCH and the reception of the PDSCH is less than the threshold. as well as If the second offset value is less than the threshold and the terminal supports the default beam selection for the PDSCH, data on the PDSCH is received from the scheduled cell of the base station based on information related to the TCI state with the lowest TCI state ID in the active transmission configuration indication TCI state in the active BWP of the scheduled cell.

3. The method according to claim 1, further comprising: If the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, the terminal supports the default beam selection for the PDSCH, and the DCI does not include a TCI field, data on the PDSCH is received from the scheduled cell of the base station based on information related to the TCI state with the lowest TCI state ID in the active TCI state of the active BWP in the scheduled cell.

4. The method according to claim 1, further comprising: The terminal's capability information is sent to the base station, the capability information including information indicating that the terminal supports the default beam selection for the PDSCH.

5. The method according to claim 4, wherein, The capability information also includes information related to the threshold.

6. A method performed by a base station in a wireless communication system, the method comprising: Send cross-carrier scheduling configuration to the terminal, the cross-carrier scheduling configuration including information indicating that the carrier indicator field CIF is included in the downlink control information DCI; On the Physical Downlink Control Channel (PDCCH), the DCI for scheduling the Physical Downlink Shared Channel (PDSCH) is sent from the scheduling cell of the base station to the terminal, and the DCI includes the CIF; as well as If the CIF indicates that the PDSCH resources are allocated to the scheduling cell, data related to the PDSCH is sent from the scheduling cell of the base station to the terminal. Wherein, if the first offset value between the transmission of the PDCCH and the transmission of the PDSCH is less than a threshold and the terminal supports default beam selection for the PDSCH, the data is associated with the quasi-parameter QCL parameter of the control resource set CORESET associated with the search space having the lowest CORESET identifier ID within the active bandwidth portion (BWP) of the scheduling cell in the most recent time slot as monitored by the terminal.

7. The method according to claim 6, further comprising: If the CIF indicates that the resources of the PDSCH are allocated to the scheduled cell of the base station, data is sent from the scheduled cell of the base station to the terminal on the PDSCH. Wherein, if the second offset value between the transmission of the PDCCH and the transmission of the PDSCH is less than the threshold and the terminal supports the default beam selection for the PDSCH, the data is associated with information related to the TCI state with the lowest TCI state ID in the active transmission configuration indication TCI state in the active BWP of the scheduled cell.

8. The method according to claim 6, further comprising: in, When the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, the terminal supports the default beam selection for the PDSCH, and the DCI does not include a TCI field, the data is associated with information related to the TCI state with the lowest TCI state ID in the active TCI state of the active BWP in the scheduled cell.

9. The method according to claim 6, further comprising: The terminal receives capability information from the terminal, the capability information including information indicating that the terminal supports the default beam selection for the PDSCH.

10. The method according to claim 9, wherein, The capability information also includes information related to the threshold.

11. A terminal in a wireless communication system, the terminal comprising: transceiver; as well as A controller, connected to the transceiver, and the controller is configured to: The system receives cross-carrier scheduling configuration from the base station, which includes information indicating that the Carrier Indicator Field (CIF) is included in the Downlink Control Information (DCI). On the Physical Downlink Control Channel (PDCCH), the DCI for scheduling the Physical Downlink Shared Channel (PDSCH) is received from the scheduling cell of the base station, the DCI including the CIF. If the CIF indicates that the resources for the PDSCH are allocated to the scheduled cell, it is determined whether a first offset value between the reception of the PDCCH and the reception of the PDSCH is less than a threshold, and If the first offset value is less than the threshold and the terminal supports default beam selection for the PDSCH, data on the PDSCH is received from the scheduling cell of the base station based on the quasi-parameter QCL parameter of the control resource set CORESET associated with the search space having the lowest CORESET identifier ID within the active bandwidth portion BWP of the scheduling cell in the most recent time slot as monitored by the terminal.

12. The terminal according to claim 11, wherein, The controller is also configured to: If the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, identify whether the second offset value between the reception of the PDCCH and the reception of the PDSCH is less than the threshold. as well as If the second offset value is less than the threshold and the terminal supports the default beam selection for the PDSCH, data on the PDSCH is received from the scheduled cell of the base station based on information related to the TCI state with the lowest TCI state ID in the active transmission configuration indication TCI state in the active BWP of the scheduled cell.

13. The terminal according to claim 11, wherein, The controller is also configured to: If the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, the terminal supports the default beam selection for the PDSCH, and the DCI does not include a TCI field, data on the PDSCH is received from the scheduled cell of the base station based on information related to the TCI state with the lowest TCI state ID in the active TCI state of the active BWP in the scheduled cell.

14. The terminal according to claim 11, wherein, The controller is also configured to: The terminal's capability information is sent to the base station, the capability information including information indicating that the terminal supports the default beam selection for the PDSCH.

15. The terminal according to claim 14, wherein, The capability information also includes information related to the threshold.

16. A base station in a wireless communication system, the base station comprising: transceiver; as well as A controller, connected to the transceiver, and the controller is configured to: Send cross-carrier scheduling configuration to the terminal, the cross-carrier scheduling configuration including information indicating that the carrier indicator field CIF is included in the downlink control information DCI; On the Physical Downlink Control Channel (PDCCH), the DCI for scheduling the Physical Downlink Shared Channel (PDSCH) is sent from the scheduling cell of the base station to the terminal, and the DCI includes the CIF; as well as If the CIF indicates that the PDSCH resources are allocated to the scheduling cell, data related to the PDSCH is sent from the scheduling cell of the base station to the terminal. Wherein, if the first offset value between the transmission of the PDCCH and the transmission of the PDSCH is less than a threshold and the terminal supports default beam selection for the PDSCH, the data is associated with the quasi-parameter QCL parameter of the control resource set CORESET associated with the search space having the lowest CORESET identifier ID within the active bandwidth portion (BWP) of the scheduling cell in the most recent time slot as monitored by the terminal.

17. The base station according to claim 16, in, The controller is also configured to: If the CIF indicates that the resources of the PDSCH are allocated to the scheduled cell of the base station, data is sent from the scheduled cell of the base station to the terminal on the PDSCH. Wherein, if the second offset value between the transmission of the PDCCH and the transmission of the PDSCH is less than the threshold and the terminal supports the default beam selection for the PDSCH, the data is associated with information related to the TCI state with the lowest TCI state ID in the active transmission configuration indication TCI state in the active BWP of the scheduled cell.

18. The base station according to claim 16, in, When the CIF indicates that the PDSCH resource is allocated to the scheduled cell of the base station, the terminal supports the default beam selection for the PDSCH, and the DCI does not include a TCI field, the data is associated with information related to the TCI state with the lowest TCI state ID in the active TCI state of the active BWP in the scheduled cell.

19. The base station of claim 16, wherein the controller is further configured to: The terminal receives capability information from the terminal, the capability information including information indicating that the terminal supports the default beam selection for the PDSCH.

20. The base station according to claim 19, wherein, The capability information also includes information related to the threshold.

Images