Method and apparatus for receiving downlink control information in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present disclosure relates to a method performed by a terminal in a wireless communication system, the method comprising the steps of: receiving downlink control information (DCI) including a bandwidth part (BWP) indicator field and a first field from a base station; and performing DCI size alignment on a first field included in the DCI and a second field corresponding to the first field, the second field being a field required for DCI format interpretation of the BWP indicated by the BWP indicator field, in which the DCI is related to multi-cell scheduling, and if the first field includes a plurality of first blocks corresponding to respective cells configured for multi-cell scheduling, performing DCI size alignment on the first field and the second field corresponding to the first field, the second field being a field required for DCI format interpretation of the BWP indicated by the BWP indicator field, if so, DCI size alignment may be applied in units of each block.

Description

Technical Field

[0001] This disclosure relates to the operation of terminals and base stations in a communication system. Specifically, this disclosure relates to a method and apparatus for a terminal to transmit and receive data via multiple cells using a single downlink control information. Background Technology

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services. It can be implemented not only in the "sub-6 GHz" band, such as 3.5 GHz, but also in the "above 6 GHz" band (including 28 GHz and 39 GHz), known as millimeter waves. Furthermore, the implementation of 6G mobile communication technology (called "super 5G systems") in terahertz bands (e.g., the 95 GHz to 3 THz band) is being considered to achieve transmission rates fifty times faster than 5G and ultra-low latency one-tenth that of 5G.

[0003] In the early stages of 5G mobile communication technology development, to support services and meet performance requirements related to enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC), standardization has been underway for the following technologies: beamforming and massive MIMO for reducing radio wave path loss and increasing radio wave transmission distance in millimeter waves; support parameter sets for dynamic operation (e.g., operating multiple subcarrier spacings) for efficient utilization of millimeter wave resources and time slot formats; initial access technologies for supporting multi-beam transmission and broadband; definition and operation of BWP (bandwidth portion); new channel coding methods such as LDPC (low-density parity-check) codes for large data transmissions and polar codes for highly reliable transmission of control information; layer 2 (L2) preprocessing; and network slicing for providing dedicated networks for specific services.

[0004] Currently, given the services supported by 5G mobile communication technology, discussions are underway regarding improvements and performance enhancements to the initial 5G mobile communication technology. Physical layer standardization has been implemented for technologies such as: V2X (Vehicle-to-Everything) for assisting autonomous vehicles in making driving decisions and improving user convenience based on information transmitted by the vehicle regarding its location and status; NR-U (New Radio Unlicensed) designed to ensure system operation complies with various regulatory requirements in unlicensed frequency bands; NR UE power saving; Non-Terrestrial Network (NTN), i.e., UE-satellite direct communication, for providing coverage in areas where terrestrial network communication is unavailable; and positioning.

[0005] Furthermore, standardization is underway for air interface architectures / protocols for technologies such as: Industrial Internet of Things (IIoT) to support new services through interoperability and convergence with other industries; Integrated Access and Backhaul (IAB) for nodes to provide network service area extension by supporting wireless backhaul and access links in an integrated manner; mobility enhancements including conditional handover and DAPS (Dual Active Protocol Stack) handover; and two-step random access (two-step RACH for NR) to simplify the random access process. Standardization is also underway for system architectures / services for technologies such as: 5G baseline architectures (e.g., service-based architectures or service-based interfaces) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies; and Mobile Edge Computing (MEC) for receiving services based on UE location.

[0006] With the commercialization of 5G mobile communication systems, the number of connected devices will increase exponentially, necessitating enhanced functionality and performance of 5G mobile communication systems as well as integrated operation of connected devices. To this end, new research is planned related to the following technologies: Extended Reality (XR) for efficient support of AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality), etc.; 5G performance improvements and complexity reduction through the utilization of Artificial Intelligence (AI) and Machine Learning (ML); AI service support; Metaverse service support; and drone communication.

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

[0008] As mentioned above, and with the advancement of wireless communication systems capable of providing diverse services, there is a need to ensure methods for efficiently delivering these services. Summary of the Invention

[0009] Technical issues

[0010] The embodiments described herein are intended to provide an apparatus and method for efficiently providing services in a mobile communication system.

[0011] Problem Solution

[0012] This disclosure presents a method and apparatus for determining scheduled cells in a communication system.

[0013] This disclosure proposes a method for indicating the cells to be scheduled in a DCI used for scheduling multiple cells.

[0014] In this disclosure, a method performed by a UE in a wireless communication system may include: receiving downlink control information from a base station including a bandwidth portion (BWP) indicator field and a first field; and performing DCI size alignment on the first field and a second field corresponding to the first field included in the DCI, the second field being a field required for DCI format interpretation of the BWP indicated by the BWP indicator field, wherein the DCI may be associated with multi-cell scheduling, and DCI size alignment may be applied on a per-block basis when the first field includes a plurality of first blocks corresponding to various cells configured for multi-cell scheduling.

[0015] In this disclosure, in a UE of a wireless communication system, the UE may include: a transceiver; and a controller connected to the transceiver, wherein the controller may be configured to: receive downlink control information from a base station including a bandwidth portion (BWP) indicator field and a first field; and perform DCI size alignment on the first field and a second field corresponding to the first field included in the DCI, the second field being a field required for DCI format interpretation of the BWP indicated by the BWP indicator field corresponding to the first field, wherein the DCI may be associated with multi-cell scheduling, and DCI size alignment may be applied on a per-block basis when the first field includes a plurality of first blocks corresponding to various cells configured for multi-cell scheduling.

[0016] Advantages of the invention

[0017] The embodiments described herein provide an apparatus and method for efficiently providing services in a mobile communication system. Attached Figure Description

[0018] Figure 1 The basic structure of the time-frequency domain in a wireless communication system according to an embodiment of the present disclosure is shown.

[0019] Figure 2 The structure of frames, subframes, and time slots in a wireless communication system according to an embodiment of the present disclosure is shown.

[0020] Figure 3An example of bandwidth configuration in a wireless communication system according to an embodiment of this disclosure is shown.

[0021] Figure 4 An example of a control resource set (CORESET) used to transmit downlink control channels in a 5G wireless communication system is shown.

[0022] Figure 5 An example of the basic unit that constitutes the time and frequency resources available in the downlink control channel in 5G is shown.

[0023] Figure 6 A method for transmitting / receiving data in a wireless communication system according to embodiments of the present disclosure, taking into account downlink data channel and rate matching resources, is illustrated.

[0024] Figure 7 An example of frequency domain resource allocation for PDSCH in a wireless communication system according to an embodiment of this disclosure is shown.

[0025] Figure 8 An example of time-domain resource allocation for PDSCH in a wireless communication system according to an embodiment of this disclosure is shown.

[0026] Figure 9 An example of time-domain resource allocation based on subcarrier spacing for data channels and control channels is shown in a wireless communication system according to an embodiment of the present disclosure.

[0027] Figure 10 The wireless protocol structures of a base station and a UE in a wireless communication system according to embodiments of the present disclosure are shown in single-cell, carrier aggregation, and dual-connectivity scenarios.

[0028] Figure 11 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0029] Figure 12 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0030] Figure 13 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0031] Figure 14 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0032] Figure 15 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0033] Figure 16 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0034] Figure 17 An example of DCI field length alignment according to an embodiment of this disclosure is shown.

[0035] Figure 18 The structure of a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0036] Figure 19 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown. Detailed Implementation

[0037] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0038] In describing the embodiments, descriptions related to technical content well-known in the relevant art and not directly related to this disclosure will be omitted. This omission of unnecessary descriptions is to prevent obscuring the main ideas of this disclosure and to more clearly convey them.

[0039] For the same reason, some elements may be exaggerated, omitted, or shown schematically in the accompanying drawings. Additionally, the size of each element does not perfectly reflect its actual size. In the corresponding drawings, the same or corresponding elements are assigned the same reference numerals.

[0040] The advantages and features of this disclosure, as well as its implementation, will become apparent from the embodiments described in detail below with reference to the accompanying drawings. However, this disclosure is not limited to the embodiments set forth below, but can be implemented in various different forms. The following embodiments are provided merely to fully disclose this disclosure and to inform those skilled in the art of its scope, and this disclosure is limited only by the scope of the appended claims. Throughout this disclosure, the same or similar reference numerals denote the same or similar elements. Furthermore, in describing this disclosure, descriptions of known functions or configurations incorporated herein will be omitted where it is determined that such detailed descriptions would unnecessarily obscure the subject matter of the 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 custom. Therefore, the definition of the terminology should be determined based on the content throughout the specification.

[0041] In the following description, a base station is an entity that allocates resources to terminals and can be at least one of a gNode B, eNode B, Node B, base station (BS), radio access unit, base station controller, and nodes on a network. A terminal can include a user equipment (UE), mobile station (MS), cellular phone, smartphone, computer, or multimedia system capable of performing communication functions. In this disclosure, "downlink (DL)" refers to a radio link through which a base station transmits signals to a terminal, and "uplink (UL)" refers to a radio link through which a terminal transmits signals to a base station. Furthermore, in the following description, LTE or LTE-A systems are described as examples, but embodiments of this disclosure can also be applied to other communication systems with similar technical backgrounds or channel types. Examples of such communication systems can include fifth-generation mobile communication technologies (5G, New Radio, and NR) developed after LTE-A, and in the following description, "5G" can be a concept encompassing existing LTE, LTE-A, and other similar services. Additionally, based on the assessment of those skilled in the art, this disclosure can be applied to other communication systems with modifications without significantly departing from its scope.

[0042] In this document, it should be understood that each box in the flowchart illustration, and combinations of boxes in the flowchart illustration, 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 the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more flowchart boxes. These computer program instructions can also be stored in a computer-usable or computer-readable storage medium that can direct 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 produce an article of writing including instruction means that implement the functions specified in the one or more flowchart boxes. The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus, thereby producing a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowchart boxes.

[0043] Furthermore, each box in the flowchart diagram can represent a module, code segment, or code section, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions mentioned in the boxes may occur out of order. For example, two boxes shown consecutively may actually execute substantially simultaneously, or the boxes may sometimes execute in reverse order, depending on the functions involved.

[0044] As used in embodiments of this disclosure, the term "unit" refers to a software element or hardware element, such as a field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC), and a "unit" can perform certain functions. However, "unit" is not always limited to software or hardware. A "unit" can be configured to be stored in addressable storage media or to execute one or more processors. Thus, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, flows, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" can be combined into a smaller number of elements or "units," or divided into a larger number of elements or "units." Furthermore, elements and "units" can be implemented as one or more CPUs within a playback device or a secure multimedia card. Additionally, a "unit" in the embodiments may include one or more processors.

[0045] Wireless communication systems are evolving into broadband wireless communication systems that use communication standards to provide high-speed and high-quality packet data services as well as typical voice-based services. These communication standards include 3GPP High-Speed ​​Packet Access (HSPA), LTE (Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2 High-Speed ​​Packet Data (HRPD), Ultra Mobile Broadband (UMB), IEEE 802.16e, etc.

[0046] As a typical example of a broadband wireless communication system, the LTE system employs Orthogonal Frequency Division Multiplexing (OFDM) in the downlink (DL) and Single-Carrier Frequency Division Multiple Access (SC-FDMA) in the uplink (UL). The uplink refers to the radio link through which a User Equipment (UE) or Mobile Station (MS) transmits data or control signals to a Base Station (BS) (or eNode B), and the downlink refers to the radio link through which the Base Station transmits data or control signals to the UE. These multiple access schemes can separate the data or control information of each user by allocating and manipulating time-frequency resources for transmitting data or control information to each user, thereby avoiding overlap and establishing orthogonality.

[0047] As a post-LTE communication system, 5G communication systems must flexibly respond to various requirements from users, service providers, and others, and therefore must support services that meet diverse needs. Services considered in 5G communication systems include enhanced mobile broadband (eMBB) communication, massive machine-type communication (mMTC), and ultra-reliable low-latency communication (URLLC), among others.

[0048] eMBB aims to provide higher data rates than those supported by existing LTE, LTE-A, or LTE-Pro systems. For example, in a 5G communication system, for a single base station, eMBB must provide a peak data rate of 20 Gbps in the downlink and 10 Gbps in the uplink. Furthermore, 5G communication systems must provide increased user-aware data rates and maximum data rates to the UE. To meet these requirements, improved transmit / receive technologies, including further enhanced multiple-input multiple-output (MIMO) transmission techniques, are needed. Additionally, the data rates required by 5G communication systems can be achieved using frequency bandwidths greater than 20 MHz in the 3 to 6 GHz or 6 GHz or higher frequency bands, rather than using the maximum 20 MHz transmission bandwidth in the 2 GHz band used in LTE.

[0049] Furthermore, in 5G communication systems, mMTC is considered to support application services such as the Internet of Things (IoT). To efficiently deliver IoT, mMTC has requirements such as supporting connections for a large number of UEs within a cell, enhancing UE coverage, increasing battery life, and reducing UE costs. Since IoT needs to provide communication capabilities while supplying various sensors and devices, it must support a large number of UEs within a cell (e.g., 1,000,000 UEs / km). 2 Additionally, mMTC-enabled UEs may require wider coverage than other services provided by 5G communication systems because the UE is likely to be located in shaded areas such as building basements, which are not covered by the cell due to the nature of the service. mMTC-enabled UEs must be configured to be inexpensive and may require very long battery life (e.g., 10 to 15 years) because it is difficult to frequently replace the UE's battery.

[0050] Finally, URLLC is a mission-critical wireless communication service based on cellular networks. For example, URLLC can be used for services such as remote control of robots or machines, industrial automation, drone-based remote healthcare, and emergency alerts. Therefore, URLLC must provide communication with ultra-low latency and ultra-high reliability. For example, services supporting URLLC should meet an air interface latency of less than 0.5 ms and also require 10... -5 Or even lower packet error rates. Therefore, for services that support URLLC, 5G systems must provide shorter Transmission Time Intervals (TTIs) than other services, and may also require designs that allocate significant resources within frequency bands to ensure the reliability of communication links.

[0051] The three services in 5G (eMBB, URLLC, and mMTC) can be multiplexed and transmitted within a single system. In this case, different transmit / receive technologies and parameters can be used between the services to meet their varying requirements. Of course, 5G is not limited to the three services described above.

[0052] [NR Time and Frequency Resources]

[0053] The frame structure of a 5G system will be described in more detail below with reference to the accompanying drawings.

[0054] Figure 1 The basic structure of the time-frequency domain in a 5G system is shown, which is a radio resource domain used for transmitting data or control channels.

[0055] exist Figure 1 In the diagram, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of a resource in the time-frequency domain is a resource element (RE) 101, which can be defined as an orthogonal frequency division multiplexing (OFDM) symbol 102 on the time axis and a subcarrier 103 on the frequency axis. In the frequency domain, (For example, 12 consecutive REs can form a resource block (RB) 104.

[0056] Figure 2 The structure of frames, subframes, and time slots in a wireless communication system according to an embodiment of the present disclosure is shown.

[0057] exist Figure 2 An example of the structure of frame 200, subframe 201, and time slot 202 is shown. A frame 200 can be defined as 10 ms. A subframe 201 can be defined as 1 ms, and therefore a frame 200 can include a total of 10 subframes 201. A time slot 202 or 203 can be defined as 14 OFDM symbols (i.e., the number of symbols per time slot). =14). A subframe 201 may include one or more time slots 202 and 203, and the number of time slots 202 and 203 in each subframe 201 may vary depending on the configuration value µ 204 or 205 for the subcarrier spacing. Figure 2 The examples illustrate the cases where the subcarrier spacing configuration value is µ=0 (204) and µ=1 (205). In the case of µ=0 (204), a subframe 201 may include one time slot 202, and in the case of µ=1 (205), a subframe 201 may include two time slots 203. That is, the number of time slots in each subframe... The number of time slots per frame can vary depending on the subcarrier spacing configuration value μ. They can be different accordingly. and The value μ can be defined based on the configuration of each subcarrier spacing, as shown in Table 1 below.

[0058] [Table 1]

[0059] [Bandwidth Component (BWP)]

[0060] The bandwidth portion (BWP) configuration in a 5G communication system will now be described in detail with reference to the accompanying drawings.

[0061] Figure 3 An example of bandwidth configuration in a wireless communication system according to an embodiment of this disclosure is shown.

[0062] Figure 3 An example is shown where the UE bandwidth 300 is configured to include two bandwidth portions (i.e., bandwidth portion #1 (BWP#1) 301 and bandwidth portion #2 (BWP#2) 302). The base station can configure one or more bandwidth portions for the UE, and can configure the following multiple pieces of information as shown in Table 2 for each bandwidth portion.

[0063] [Table 2]

[0064] Obviously, the above examples are not limiting, and various parameters related to bandwidth can be configured for the UE in addition to the configuration information described above. The base station can transmit configuration information to the UE via upper-layer signaling (e.g., Radio Resource Control (RRC) signaling). A configured bandwidth portion or at least one of multiple configured bandwidth portions can be activated. Whether a configured bandwidth portion is activated can be transmitted from the base station to the UE semi-statically via RRC signaling or dynamically via downlink control information (DCI).

[0065] According to some embodiments, prior to Radio Resource Control (RRC) connection, the base station can configure an Initial Bandwidth Part (BWP) for initial access for the UE via the Master Information Block (MIB). More specifically, during the initial access step, the UE can receive configuration information about the Control Resource Set (CORESET) and the search space via the MIB. The CORESET and search space can be used to transmit system information required for receiving initial access (which may correspond to the Residual System Information (RMSI) or System Information Block 1 (SIB1) PDCCH). Each of the CORESET and search space configured via the MIB can be considered as ID 0. The base station can notify the UE of configuration information about the Control Resource Set #0 via the MIB, such as frequency allocation information, time allocation information, and parameter sets. Additionally, the base station can notify the UE of configuration information about the monitoring period and timing for the Control Resource Set #0 via the MIB, i.e., configuration information about the search space #0. The UE can consider the frequencies configured for the Control Resource Set #0 obtained from the MIB as the Initial Bandwidth Part for initial access. The ID of the Initial Bandwidth Part can be considered as 0.

[0066] The bandwidth and related configurations supported by 5G can be used for various purposes.

[0067] According to some embodiments, if the bandwidth supported by the UE is less than the system bandwidth, this can be supported through bandwidth portion configuration. For example, the base station can configure the frequency position of the bandwidth portion for the UE (configuration information 2), so that the UE can send / receive data at a specific frequency position within the system bandwidth.

[0068] Furthermore, according to some embodiments, the base station can configure multiple bandwidth portions for the UE to support different parameter sets. For example, to support the UE in transmitting / receiving data using a 15kHz subcarrier spacing and a 30kHz subcarrier spacing, the two bandwidth portions can be configured with subcarrier spacings of 15kHz and 30kHz, respectively. The different bandwidth portions can be frequency-division multiplexed (FDM), and the bandwidth portion configured for the corresponding subcarrier spacing can be activated if data is transmitted / received at a specific subcarrier spacing.

[0069] Additionally, according to embodiments, the base station can configure bandwidth portions with different bandwidth sizes for the UE to reduce the power consumed by the UE. For example, if the UE supports a fairly large bandwidth (e.g., 100MHz) and always transmits / receives data using the corresponding bandwidth, a considerable amount of power consumption may occur. In particular, from a power consumption perspective, unnecessarily monitoring the downlink control channel with a large bandwidth can be quite inefficient. To reduce the power consumed by the UE, the base station can configure a relatively small bandwidth portion for the UE (e.g., a 20MHz bandwidth portion). In the absence of service, the UE can perform monitoring operations in the 20MHz bandwidth portion, and if data is received, it can transmit / receive data using the 100MHz bandwidth portion as instructed by the base station.

[0070] Regarding the bandwidth configuration method, the UE can receive configuration information about the initial bandwidth portion via the MIB during the initial access step before RRC connection. More specifically, the UE can have a control resource set (CORESET) configured for the downlink control channel from the MIB of the Physical Broadcast Channel (PBCH), which can be used to transmit downlink control information (DCI) for scheduling System Information Blocks (SIBs). The bandwidth of the control resource set configured via the MIB can be regarded as the initial bandwidth portion, and the UE can receive the Physical Downlink Shared Channel (PDSCH) used for transmitting SIBs through the configured initial bandwidth portion. The initial bandwidth portion can be used not only for receiving SIBs but also for other System Information (OSI), paging, or random access, etc.

[0071] If a UE has one or more bandwidth portions configured for it, the base station can instruct the UE to change (or switch or switch) the bandwidth portion by using the bandwidth portion indicator field within the DCI. As an example, if the UE's currently active bandwidth portion is... Figure 3 If the bandwidth portion #1 301 is in the DCI, the base station can indicate the bandwidth portion #2 302 using the bandwidth portion indicator in the DCI, and the UE can change the bandwidth portion to the bandwidth portion #2 302 indicated by the bandwidth portion indicator in the received DCI.

[0072] As mentioned above, bandwidth portion changes based on DCI can be indicated by the DCI used to schedule PDSCH or PUSCH. Therefore, upon receiving a bandwidth portion change request, the UE needs to be able to receive or transmit PDSCH or PUSCH scheduled by the corresponding DCI without any problems within the changed bandwidth portion. To this end, the standard specifies the required delay time (T) during the bandwidth portion change. BWP The requirements for ( ) can be defined, for example, as given in Table 3.

[0073] [Table 3]

[0074] The requirement for bandwidth portion change delay time supports either Type 1 or Type 2, depending on the UE's capabilities. The UE can report the supported bandwidth portion change delay time types to the base station.

[0075] If the UE receives a DCI including a bandwidth partial change indicator in time slot n, then according to the above requirements regarding the bandwidth partial change delay time, the UE can proceed no later than time slot n+T. BWP The change to the new bandwidth portion indicated by the bandwidth portion change indicator is completed at the specified time, and data channels scheduled by the corresponding DCI can be transmitted / received in the newly changed bandwidth portion. If the base station wants to schedule data channels using the new bandwidth portion, the base station can consider the UE's bandwidth portion change delay time (T). BWP This is used to determine the temporal resource allocation for the data channel. In other words, when scheduling a data channel using a new bandwidth portion, combined with the method used to determine the temporal resource allocation for the data channel, the base station can schedule the corresponding data channel after the bandwidth portion change delay time. Therefore, the UE may not expect the DCI indication indicating the bandwidth portion change to be less than the bandwidth portion change delay time (T). BWP The time slot offset (K0 or K2) value.

[0076] If the UE receives a DCI indicating a partial change in bandwidth (e.g., DCI format 1_1 or 0_1), the UE may refrain from transmitting or receiving for the time interval from the third symbol of the slot used to receive the PDCCH including the corresponding DCI to the start point of the slot indicated by the slot offset (K0 or K2) value indicated by the time domain resource allocation indicator field in the corresponding DCI. For example, if the UE receives a DCI indicating a partial change in bandwidth in slot n, and if the slot offset value indicated by the corresponding DCI is K, the UE may refrain from transmitting or receiving from the third symbol of slot n to the symbols preceding slot n+K (e.g., the last symbol of slot n+K-1).

[0077] [SS / PBCH block]

[0078] Next, the synchronization signal (SS) / PBCH block in 5G will be described.

[0079] The SS / PBCH block can refer to a physical layer channel block that includes the primary synchronization signal (PSS), secondary synchronization signal (SSS), and PBCH. Details are as follows.

[0080] - PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides partial information about the cell ID.

[0081] - SSS: Serves as a reference for downlink time / frequency synchronization and provides residual cell ID information not provided by PSS. Additionally, SSS can be used as a reference signal for PBCH demodulation.

[0082] - PBCH: The MIB that provides mandatory system information necessary for the UE to transmit / receive data and control channels. Mandatory system information may include search space-related control information indicating radio resource mapping information for control channels, scheduling control information for separate data channels used to transmit system information, etc.

[0083] - SS / PBCH Blocks: SS / PBCH blocks consist of a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks can be sent within a 5 ms time period, and each sent SS / PBCH block can be distinguished by an index.

[0084] The UE can detect the PSS and SSS and decode the PBCH during the initial access phase. The UE can obtain the MIB from the PBCH, and this can be used to configure the control resource set (CORESET) #0 (which may correspond to a control resource set with a control resource set index of 0). The UE can monitor the control resource set #0 by assuming that the demodulation reference signal (DMRS) transmitted in the selected SS / PBCH block and control resource set #0 is quasi-co-located (QCLed). The UE can use the downlink control information transmitted in control resource set #0 to receive system information. The UE can obtain configuration information related to the random access channel (RACH) required for initial access from the received system information. The UE can transmit the physical RACH (PRACH) to the base station based on the selected SS / PBCH block index, and the base station can obtain information about the SS / PBCH block index selected by the UE upon receiving the PRACH. The base station can know which block the UE has selected from the corresponding SS / PBCH block and can know that the associated control resource set #0 is being monitored.

[0085] [PDCCH: About DCI]

[0086] Next, we will describe downlink control information (DCI) in 5G systems in detail.

[0087] In 5G systems, scheduling information for uplink data (or Physical Uplink Shared Channel (PUSCH)) or downlink data (or Physical Downlink Shared Channel (PDSCH)) is included in the DCI and transmitted from the base station to the UE via the DCI. The UE can monitor the fallback DCI format and the non-fallback DCI format for either the PUSCH or the PDSCH. The fallback DCI format may include predefined fixed fields between the base station and the UE, while the non-fallback DCI format may include configurable fields.

[0088] The DCI message can undergo channel coding and modulation processing, and then be 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's identifier. Different RNTIs can be used depending on the purpose of the DCI message (e.g., UE-specific data transmission, power control command, or random access response). That is, the RNTI may not be explicitly sent, but can be sent during the CRC calculation process. Upon receiving a DCI message transmitted via the PDCCH, the UE can identify the CRC using the assigned RNTI, and if the CRC identification result is correct, the UE knows that the corresponding message has been sent.

[0089] For example, the DCI used for scheduling PDSCH about System Information (SI) can be scrambled by SI-RNTI. The DCI used for scheduling PDSCH about Random Access Response (RAR) messages can be scrambled by RA-RNTI. The DCI used for scheduling PDSCH about paging messages can be scrambled by P-RNTI. The DCI used for notifying Slot Format Indicator (SFI) can be scrambled by SFI-RNTI. The DCI used for notifying Transmit Power Control (TPC) can be scrambled by TPC-RNTI. The DCI used for scheduling UE-specific PDSCH or PUSCH can be scrambled by Cell RNTI (C-RNTI).

[0090] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, and in this case, CRC can be scrambled by C-RNTI. For example, DCI format 0_0 with CRC scrambled by C-RNTI can include the following information given in Table 4.

[0091] [Table 4]

[0092] DCI format 0_1 ​​can be used as a non-back-off DCI for scheduling PUSCH, and in this case, CRC can be scrambled by C-RNTI. For example, DCI format 0_1 ​​with CRC scrambled by C-RNTI can include the following information given in Table 5.

[0093] [Table 5]

[0094] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, and in this case, CRC can be scrambled by C-RNTI. For example, DCI format 1_0 with CRC scrambled by C-RNTI can include the following information given in Table 6 below.

[0095] [Table 6]

[0096] DCI format 1_1 can be used as a non-back-off DCI for scheduling PDSCH, and in this case, CRC can be scrambled by C-RNTI. For example, DCI format 1_1 with CRC scrambled by C-RNTI can include the following information given in Table 7.

[0097] [Table 7]

[0098] [PDCCH: CORESET, REG, CCE, and Search Space]

[0099] The downlink control channel in a 5G communication system will be described in more detail below with reference to the accompanying drawings.

[0100] Figure 4 An example of a control resource set (CORESET) used to transmit downlink control channels in a 5G wireless communication system is shown. Figure 4 An example is shown where the UE bandwidth portion 410 is configured along the frequency axis and two control resource sets (control resource set #1 420 and control resource set #2 401) are configured along the time axis within a time slot 402. Control resource sets 401 and 402 can be configured along the frequency axis within a specific frequency resource 410 throughout the entire UE bandwidth portion 403. Control resource sets 401 and 402 can each be configured along one or more OFDM symbols in the time domain, and the number of OFDM symbols can be defined as the control resource set duration 404. Reference Figure 4In the example shown, control resource set #1 401 is configured to have a control resource set duration corresponding to two symbols, and control resource set #2 402 is configured to have a control resource set duration corresponding to one symbol.

[0101] The base station can configure the control resource set in 5G as described above for the UE via upper-layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). Configuring the control resource set for the UE means providing information such as the control resource set identifier, the frequency location of the control resource set, and the symbol duration of the control resource set. For example, the control resource set may include several pieces of information as given in Table 8 below.

[0102] [Table 8]

[0103] In Table 8, the tci-StatesPDCCH (Transmission Configuration Indication (TCI) status) configuration information may include information on one or more SS / PBCH block indices or Channel State Information Reference Signal (CSI-RS) indices that are co-located with the DMRS quasi-co-located with the corresponding control resource centrally transmitted.

[0104] Figure 5 An example of the basic units constituting the time and frequency resources available in the downlink control channel in 5G is shown. Figure 5 The basic unit constituting the time and frequency resources of the control channel can be called a resource element group (REG) 503, and REG 503 can be defined by an OFDM symbol 501 along the time axis and a physical resource block (PRB) 502 (i.e., 12 subcarriers) along the frequency axis. The base station can configure the downlink control channel allocation unit by cascading REG 503.

[0105] Assuming Figure 5 As shown, the basic unit for downlink control channel allocation in 5G is the control channel element 504, and one CCE 504 can include multiple REG 503s. To describe... Figure 5 The REG 503 shown may, for example, include 12 REs, and if a CCE 504 includes six REs 503, then a CCE 504 may include 72 REs. Once configured, a downlink control resource set can include multiple CCE 504s, and based on the aggregation level (AL) in the control resource set, a specific downlink control channel can be mapped to one or more CCE 504s and then transmitted. CCE 504s in the control resource set are distinguished by numbering, and the numbers of the CCE 504s can be assigned according to a logical mapping scheme.

[0106] Figure 5 The basic unit of the downlink control channel shown (i.e., REG 503) can include both the RE mapped to by the DCI and the region mapped to by the reference signal (DMRS 505) used for decoding it. Figure 5 As shown, three DMRS 503s can be transmitted within one REG 505. Depending on the aggregation level (AL), the number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16, and different numbers of CCEs can be used to implement link adaptation for the downlink control channel. For example, in the case of AL=L, a downlink control channel can be transmitted with L CCEs. The UE needs to detect the signal without information about the downlink control channel; therefore, a search space indicating a set of CCEs has been defined for blind decoding. The search space is the set of downlink control channel candidates, which includes the CCEs that the UE needs to attempt to decode under a given AL. Since 1, 2, 4, 8, or 16 CCEs can form a bundle under each AL, the UE can have multiple search spaces. The search space set can be defined as the set of search spaces under all configured aggregation levels.

[0107] The search space can be categorized into a common search space and a UE-specific search space. A group of UEs or all UEs can search the common search space of the PDCCH to receive cell common control information, such as dynamic scheduling of system information or paging messages. For example, searching the common search space of the PDCCH can be used to receive PDSCH scheduling allocation information for transmitting SIBs (including cell operator information, etc.). In the case of the common search space, a group of UEs or all UEs need to receive the PDCCH, and therefore the common search space can be defined as a predetermined set of CCEs. Searching the UE-specific search space of the PDCCH can be used to receive scheduling allocation information for UE-specific PDSCHs or PUSCHs. The UE-specific search space can be defined in a UE-specific manner based on various system parameters and the UE's identifier.

[0108] In 5G, the base station can configure parameters for the UE regarding the search space for PDCCH via upper-layer signaling (e.g., SIB, MIB, or RRC signaling). For example, the base station can provide the UE with configurations such as the number of PDCCH candidates under each aggregation level L, the monitoring period for the search space, the monitoring timing for each symbol in the time slot of the search space, the search space type (public search space or UE-specific search space), the combination of RNTI and DCI formats to be monitored in the corresponding search space, and the control resource set index used for monitoring the search space. For example, the control resource set may include several pieces of information as shown in Table 9 below.

[0109] [Table 9]

[0110] Based on the configuration information, the base station can configure one or more search space sets for the UE. According to some embodiments, the base station can configure search space set 1 and search space set 2 for the UE, and can configure DCI format A scrambled by X-RNTI to be monitored in the common search space in search space set 1, and can configure DCI format B scrambled by Y-RNTI to be monitored in the UE-specific search space in search space set 2.

[0111] Depending on the configuration information, one or more search space sets may exist in the public search space or the UE-specific search space. For example, search space set #1 and search space set #2 can be configured as a public search space, and search space set #3 and search space set #4 can be configured as UE-specific search spaces.

[0112] The combinations of DCI format and RNTI given below can be monitored in the public search space. Obviously, the examples given below are not restrictive.

[0113] 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.

[0114] DCI format 2_0 with CRC scrambled by SFI-RNTI

[0115] DCI format 2_1 with CRC scrambled by INT-RNTI

[0116] DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI and TPC-PUCCH-RNTI

[0117] DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0118] The combinations of DCI format and RNTI given below can be monitored within a specific search space of the UE. Obviously, the examples given below are not limiting.

[0119] DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, and TC-RNTI

[0120] DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, and TC-RNTI

[0121] The listed RNTIs can be defined and used as follows:

[0122] Cell-RNTI (C-RNTI): Used for scheduling UE-specific PDSCH

[0123] Temporary Cell RNTI (TC-RNTI): Used for scheduling UE-specific PDSCH

[0124] Configured Scheduling RNTI (CS-RNTI): Used to schedule UE-specific PDSCHs with semi-static configuration.

[0125] Random Access RNTI (RA-RNTI): Used to schedule PDSCH during the random access step.

[0126] Paging RNTI (P-RNTI): Used to schedule the PDSCH in which paging is sent.

[0127] System Information RNTI (SI-RNTI): Used to schedule the PDSCH in which system information is sent.

[0128] Interrupted RNTI (INT-RNTI): Used to indicate whether the PDSCH has been punctured.

[0129] PUSCH Transmit Power Control RNTI (TPC-PUSCH-RNTI): Used to indicate power control commands regarding the PUSCH.

[0130] PUCCH transmit power control (RNTI): Used to indicate power control commands regarding the PUCCH.

[0131] SRS Transmit Power Control RNTI (TPC-SRS-RNTI): Used to indicate power control commands regarding the SRS.

[0132] For example, the DCI formats listed above can follow the definitions given in Table 10 below.

[0133] [Table 10]

[0134] In 5G, the search space under the aggregation level L, which is related to the control resource set p and the search space set s, can be represented by the following formula 1.

[0135] [Formula 1]

[0136] - L Aggregation Level

[0137] - Carrier index

[0138] - Control resource set p The total number of CCEs existing in

[0139] - Time slot index

[0140] - The number of PDCCH candidates under aggregation level L; - = 0, ..., -1: PDCCH candidate index under aggregation level L - = 0, ..., -1 - , , , , ,

[0141] - UE identifier

[0142] In the context of public search spaces, The value can correspond to 0.

[0143] In the case of a specific search space for the UE This can correspond to a value that changes through the UE's identifier (C-RNTI or ID configured by the base station for the UE) and time index.

[0144] In 5G, multiple search space sets can be configured with different parameters (e.g., the parameters in Table 9), and the groups of search space sets monitored by the UE at each time point can be different accordingly. For example, if search space set #1 is configured with a time slot period of X, and search space set #2 is configured with a time slot period of Y, 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 one of search space set #1 and search space set #2 in another specific time slot.

[0145] [PDSCH / PUSCH: Regarding Frequency Resource Allocation]

[0146] Figure 7 An example of frequency domain resource allocation for a Physical Downlink Shared Channel (PDSCH) or Physical Uplink Shared Channel (PUSCH) in a wireless communication system according to embodiments of this disclosure is shown.

[0147] Figure 7 The diagram illustrates three frequency domain resource allocation methods that can be configured at the upper layer in an NR wireless communication system: Type-0 7-00, Type-1 7-05, and dynamic switching 7-10.

[0148] refer to Figure 7 When the UE is configured to use only resource allocation type -0 (7-00) via upper-layer signaling, the portion of downlink control information (DCI) used to allocate PDSCH to the UE includes information via N RBG A bitmap with bit configuration. As used in this article, N RBG This refers to the number of Resource Block Groups (RBGs) determined by the size of the bandwidth portion indicated by the bandwidth portion indicator and the higher-layer parameter rbg-Size (as shown in Table 11 below), and the data is sent through the RBG marked as 1 in the bitmap.

[0149] [Table 11]

[0150] BWP size refers to the number of RBs included in the BWP. More specifically, when instructing the UE to allocate FDRA type-0 resources, the length of the FDRA field in the DCI received by the UE is equal to the number of RBGs (N) within the bandwidth portion. RBG ),and The first RBG in the bandwidth section includes... The same amount of RB, and if The last RBG in the bandwidth section includes... The same amount of RB, otherwise, including with The same number of RBs. Each of the other RGB numbers consists of P RBs. Here, P refers to the nominal number of RBGs determined according to Table 11.

[0151] Resource allocation type 2

[0152] The base station can notify the UE of RB allocation information as M interleaving index sets.

[0153] Intertwined Index Through public RB Configure, and M It can be defined as shown in Table 12.

[0154] [Table 12]

[0155] Intertwined m RB in and bandwidth section i and public RB The relationship can be defined as follows.

[0156]

[0157] in It is the bandwidth portion of the common resource block relative to common resource block 0. μ is the subcarrier spacing index.

[0158] If the subcarrier spacing is 15kHz (μ=0), the base station can notify the UE of the RB allocation information for the interleaving set with (m0+l) indices. Furthermore, the resource allocation field can be configured via the resource indication value (RIV). If the RIV is... , Then RIV can be started by interleaving. m 0 and the number of consecutive interlacing ( The configuration is as follows.

[0159] if ,but

[0160] otherwise,

[0161] If RIV is Then RIV uses the starting interleaving index m 0 and l The value is used for configuration, and can be configured as shown in Table 13.

[0162] [Table 13]

[0163] If the subcarrier spacing is 30kHz (u=1), the base station can notify the UE of the RB allocation information in the form of a bitmap, which indicates the interleaving allocated to the UE. The bitmap is of size M, and each bit in the bitmap corresponds to an interleaving. The interleaving bitmap order allows the interleaving indices 0 to M-1 to be mapped from the MSB to the LSB of the bitmap.

[0164] Additionally, for 15kHz and 30kHz, the least significant bit (LSB) of the FDRA field. It can refer to a contiguous set of RBs scheduled in DCI format 0_1. The Y bit can be determined by the Resource Indicator Value (RIV). RBset Configuration. In , In the case of RIV RBset The value can be determined from the initial RB set ( ) and the number of consecutive RB sets ( Confirmed. RIV RBsetThe value can be defined as follows.

[0165] if ,but

[0166] otherwise, It refers to the number of RB sets included in the bandwidth portion, and can be determined by the number of guard gaps (or bands) within the carrier configured (or pre-configured) by higher-layer signaling.

[0167] When the UE is configured to use only resource allocation type 1 via upper-layer signaling (7-05), the DCI used to allocate PDSCH / PUSCH to the UE includes communication with... The same amount of bit-configured Frequency Domain Resource Allocation (FDRA) information. Here, This indicates the number of RBs included in the BWP. Therefore, the base station can configure the starting VRB 7-20 and the length of the frequency resources continuously allocated from it 7-25.

[0168] When a UE is configured to use both resource allocation type-0 and resource allocation type-1 (7-10) via higher-layer signaling, the portion of the DCI used to allocate the PDSCH to the corresponding UE includes frequency domain resource allocation information. This information comprises as many bits as the larger of the payload 7-15 used to configure resource allocation type-0 and the payload 7-20 and 7-25 used to configure resource allocation type-1 (7-20 and 7-25), which is 7-35. Its conditions will be described again later. A bit can be added to the very beginning (MSB) of the frequency domain resource allocation information within the DCI, and if that bit has a value of "0", it indicates the use of resource allocation type 0, and if it has a value of "1", it indicates the use of resource allocation type-1.

[0169] [PDSCH / PUSCH: Regarding Time Resource Allocation]

[0170] The following section describes a method for allocating time-domain resources for data channels in next-generation wireless communication systems (5G or NR systems).

[0171] The base station can configure tables for the UE regarding time-domain resource allocation information for the Physical Downlink Shared Channel (PDSCH) and Physical Uplink Shared Channel (PUSCH) via upper-layer signaling (e.g., RRC signaling). A table with a maximum of maxNrofDL-Allocations=16 entries can be configured for the PDSCH, and a table with a maximum of maxNrofUL-Allocations=16 entries can be configured for the PUSCH. In an embodiment, the time-domain resource allocation information may include time slot timing from PDCCH to PDSCH (e.g., a time slot unit time interval corresponding to the time point between receiving the PDCCH and sending the PDSCH scheduled by the received PDCCH; denoted as K0), time slot timing from PDCCH to PUSCH (e.g., a time slot unit time interval corresponding to the time point between receiving the PDCCH and sending the PUSCH scheduled by the received PDCCH; denoted as K2 hereinafter), information regarding the position and length of the starting symbol of the PDSCH or PUSCH scheduled within a time slot, the mapping type of the PDSCH or PUSCH, etc. For example, information such as that in Table 14 or Table 15 can be sent from the base station to the UE.

[0172] [Table 14]

[0173] [Table 15]

[0174] The base station can notify the UF of one of the entries in the table regarding the aforementioned time-domain resource allocation information via L1 signaling (e.g., DCI). (For example, the "Time-domain Resource Allocation" field in the DCI can indicate this entry.) The UE can obtain time-domain resource allocation information regarding PDSCH or PUSCH based on the DCI obtained from the base station.

[0175] Figure 8 An example of time-domain resource allocation for PDSCH in a wireless communication system according to an embodiment of this disclosure is shown.

[0176] refer to Figure 8 The base station can determine the subcarrier spacing (SCS) of the data channel and control channel by using higher-layer configuration. μ PDSCH , μ PDCCH The time-domain location of the PDSCH resource is indicated by the scheduling offset (K0) value and the OFDM symbol start position 8-00 and length 8-05 within a time slot, which are dynamically indicated by DCI.

[0177] Figure 9An example of time-domain resource allocation based on subcarrier spacing for data channels and control channels is shown in a wireless communication system according to an embodiment of the present disclosure.

[0178] refer to Figure 9 If the data channel and control channel have the same subcarrier spacing of 9-00 ( μ PDSCH =μ PDCCH If the number of time slots used for data is the same as the number of time slots used for control, the base station and UE can generate scheduling offsets that conform to the predetermined time slot offset K0 accordingly. Conversely, if the data channel and the control channel have different subcarrier spacings 9-05 ( μ PDSCH ≠ μ PDCCH If the number of time slots used for data is different from the number of time slots used for control, the base station and UE can refer to the subcarrier spacing of the PDCCH to generate a scheduling offset that conforms to the predetermined time slot offset K0.

[0179] [PUSCH: Regarding the transmission scheme]

[0180] Next, the PUSCH transport scheduling scheme will be described. PUSCH transports can be dynamically scheduled via UL authorization within the DCI, or operated by configuring authorization type 1 or type 2. Dynamic scheduling instructions for PUSCH transports can be given via DCI format 0_0 or 0_1.

[0181] PUSCH transports of configuration authorization type 1 can be semi-statically configured by receiving a configuredGrantConfig, which includes the rrc-ConfiguredUplinkGrant in Table 16, via upper-layer signaling, without receiving a UL authorization within the DCI. After receiving a configuredGrantConfig, which does not include the rrc-ConfiguredUplinkGrant in Table 16, via upper-layer signaling, PUSCH transports of configuration authorization type 2 can be semi-persistently scheduled via a UL authorization within the DCI. If PUSCH transports operate via configuration authorization, the parameters applied to the PUSCH transports are applied via the configuredGrantConfig (upper-layer signaling) in Table 16, except for scaling of dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and UCI-OnPUSCH (which are provided by pusch-Config (upper-layer signaling) in Table 17). If transformPrecoder is provided in configuredGrantConfig (upper-layer signaling) in Table 16, the UE will apply tp-pi2BPSK in pusch-Config in Table 17 to PUSCH transports via configured grant operation.

[0182] [Table 16]

[0183] Next, the PUSCH transmission method will be described. The DMRS antenna port used for PUSCH transmission is the same as the antenna port used for SRS transmission. Depending on whether the value of txConfig in pusch-Config, which serves as upper-layer signaling, is "codebook" or "non-codebook", PUSCH transmission can follow either a codebook-based transmission method or a non-codebook-based transmission method.

[0184] As described above, PUSCH transmissions can be dynamically scheduled via DCI format 0_0 or 0_1, and can be semi-statically configured via configuration authorization. Upon receiving a scheduling instruction for a PUSCH transmission via DCI format 0_0, the UE performs beam configuration for the PUSCH transmission using the pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource, which corresponds to the smallest ID within the active uplink BWP in the serving cell, and the PUSCH transmission is based on a single antenna port. The UE does not expect PUSCH transmission scheduling via DCI format 0_0 within a BWP that does not have configured PUCCH resources (including pucch-spatialRelationInfo). If the UE does not have a configured txConfig in the pusch-Config in Table 19, the UE does not expect scheduling via DCI format 0_1.

[0185] [Table 17]

[0186] The codebook-based PUSCH transmission will be described below. Codebook-based PUSCH transmission can be dynamically scheduled using DCI format 0_0 or 0_1, and can be operated semi-statically using configuration grants. If codebook-based PUSCH is dynamically scheduled using DCI format 0_1 ​​or semi-statically configured using configuration grants, the UE determines the precoder used for PUSCH transmission based on the SRS Resource Indicator (SRI), the Transport Precoding Matrix Indicator (TPMI), and the transport rank (the number of PUSCH transport layers).

[0187] The SRI can be given through the SRS resource indicator (a field within the DCI) or configured through the srs-ResourceIndicator (upper-layer signaling). During codebook-based PUSCH transmission, the UE has at least one SRS resource configured for it, and can have at most two SRS resources configured for it. If the SRI is provided to the UE through the DCI, the SRS resource indicated by the corresponding SRI refers to the SRS resource corresponding to that SRI among the SRS resources transmitted before the PDCCH including the corresponding SRI. Additionally, the TPMI and transport rank can be given through "precoding information and number of layers" (a field within the DCI) or configured through precodingAndNumberOfLayers (upper-layer signaling). The TPMI is used to indicate the precoder to be applied to the PUSCH transmission. If one SRS resource is configured for the UE, the TPMI can be used to indicate the precoder to be applied to the configured SRS resource. If multiple SRS resources are configured for the UE, the TPMI is used to indicate the precoder to be applied to the SRS resource indicated by the SRI.

[0188] The precoder to be used for PUSCH transmission is selected from an uplink codebook with the same number of antenna ports as the value of nrofSRS-Ports in the SRS-Config (upper-layer signaling). For codebook-based PUSCH transmission, the UE determines the codebook subset based on the codebookSubset and TPMI in the push-Config (upper-layer signaling). The codebookSubset in the push-Config (upper-layer signaling) can be configured as "fullAndPartialAndNonCoherent", "partialAndNonCoherent", or "nonCoherent" based on the UE capabilities reported by the UE to the base station. If the UE reports "partialAndNonCoherent" as a UE capability, the UE does not expect the value of codebookSubset (upper-layer signaling) to be configured as "fullAndPartialAndNonCoherent". Conversely, if the UE reports "nonCoherent" as a UE capability, the UE does not expect the value of codebookSubset (upper-layer signaling) to be configured as either "fullAndPartialAndNonCoherent" or "partialAndNonCoherent". If nrofSRS-Ports in SRS-ResourceSet (upper-layer signaling) indicates two SRS antenna ports, the UE does not expect the value of codebookSubset (upper-layer signaling) to be configured as "partialAndNonCoherent".

[0189] A UE can have an SRS resource set configured for it, where the usage value in the SRS-ResourceSet (upper-layer signaling) is "codebook", and an SRS resource within the corresponding SRS resource set can be indicated by an SRI. If multiple SRS resources are configured within the SRS resource set, and the usage value in the SRS-ResourceSet (upper-layer signaling) is "codebook", the UE expects the value of nrofSRS-Ports in the SRS-Resource (upper-layer signaling) to be the same for all SRS resources.

[0190] The UE sends one or more SRS resources included in the SRS resource set (where the value of usage is configured as a "codebook" according to upper-layer signaling) to the base station. The base station selects one of the SRS resources sent by the UE and indicates that the UE can transmit PUSCH by using the transmission beam information of the corresponding SRS resource. For codebook-based PUSCH transmission, the SRI is used as information for selecting an SRS resource and is included in the DCI. Additionally, the base station adds rank and TPMI information to the DCI indicating the rank to be used by the UE for PUSCH transmission. Using the SRS resource indicated by the SRI, the UE applies the precoder indicated by the rank and TPMI based on the transmission beam indication of the corresponding SRS resource when performing PUSCH transmission.

[0191] Next, non-codebook-based PUSCH transmissions will be described. Non-codebook-based PUSCH transmissions can be dynamically scheduled using DCI format 0_0 or 0_1, and can be operated semi-statically through configuration authorization. If at least one SRS resource is configured within the SRS resource set (where the usage value in the SRS-ResourceSet (upper-layer signaling) is “nonCodebook”), non-codebook-based PUSCH transmissions can be scheduled for the UE using DCI format 0_1.

[0192] For an SRS resource set with a usage value of "nonCodebook" within the SRS-ResourceSet (upper-layer signaling), a connected NZP CSI-RS resource (non-zero power CSI-RS) can be configured for the UE. The UE can calculate the precoder for SRS transmission by measuring the NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the non-periodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the non-periodic SRS transmission in the UE is less than 42 symbols, the UE does not expect the information about the precoder for SRS transmission to be updated.

[0193] If the resourceType configuration value in the SRS-ResourceSet (upper-layer signaling) is "aperiodic", the connected NZP CSI-RS can be indicated by an SRS request, which is a field within DCI format 0_1 ​​or 1_1. If the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the presence of the connected NZP CSI-RS can be indicated by a value for the SRS request (a field within DCI format 0_1 ​​or 1_1) that is not "00". The corresponding DCI should not indicate cross-carrier or cross-BWP scheduling. Alternatively, if the SRS request value indicates the presence of an NZP CSI-RS, the NZPCSI-RS is located in the time slot used to transmit the PDCCH including the SRS request field. In this case, the TCI state configured for the scheduled subcarrier is not configured as QCL-Type D.

[0194] If a periodic or semi-persistent SRS resource set is configured, the associated CSI-RS within the SRS-ResourceSet (upper-layer signaling) can indicate the connected NZP CSI-RS. For non-codebook-based transmissions, the UE does not expect the spatialRelationInfo, which is the upper-layer signaling regarding SRS resources, to be configured together with the associated CSI-RS within the SRS-ResourceSet (upper-layer signaling).

[0195] If multiple SRS resources are configured for the UE, the UE can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. The SRI can be indicated by an SRS resource indicator (a field within the DCI) or configured via the srs-ResourceIndicator (upper-layer signaling). Similar to the codebook-based PUSCH transmission described above, if the SRI is provided to the UE via the DCI, the SRS resource indicated by the corresponding SRI refers to the SRS resource corresponding to that SRI among those transmitted before the PDCCH including the corresponding SRI. The UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be transmitted simultaneously in the same symbol within an SRS resource set and the maximum number of SRS resources are determined by the UE's capabilities reported to the base station. SRS resources transmitted simultaneously by the UE occupy the same RB. The UE configures one SRS port for each SRS resource. There can be only one configured SRS resource set, where the usage value in SRS-ResourceSet (upper-layer signaling) is "nonCodebook", and a maximum of four SRS resources can be configured for non-codebook-based PUSCH transmissions.

[0196] The base station sends an NZP-CSI-RS connected to the SRS resource set to the UE, and the UE calculates the precoder to be used when sending one or more SRS resources within the corresponding SRS resource set based on the measurements received upon receiving the corresponding NZP-CSI-RS. The UE applies the calculated precoder when sending one or more SRS resources within the SRS resource set (where the configured usage is "nonCodebook") to the base station, and the base station selects one or more SRS resources from the received one or more SRS resources. For nonCodebook-based PUSCH transmissions, the SRI indication can represent an index of one or more SRS resources or a combination of SRS resources, and the SRI is included in the DCI. The number of SRS resources indicated by the SRI sent by the base station can be the number of transport layers of the PUSCH, and the UE transmits the PUSCH by applying the precoder used for SRS resource transmission to each layer.

[0197] [About CA / DC]

[0198] Figure 10 The radio protocol structures of the base station and UE in single cell, carrier aggregation and dual connectivity scenarios are shown according to embodiments of the present disclosure.

[0199] refer to Figure 10 The radio protocols of the next-generation mobile communication system include NR Service Data Adaptation Protocol (SDAP) S25 or S70, NR Packet Data Convergence Protocol (PDCP) S30 or S65, NR Radio Link Control (RLC) S35 or S60 and NR Media Access Control (MAC) S40 or S55 on each of the UE side and the NR base station side.

[0200] The main functions of NR SDAP S25 or S70 may include some of the following functions.

[0201] - Transmission of user plane data

[0202] - Mapping between QoS flows and DRB for both DL and UL

[0203] - Mark QoS flow IDs in both DL and UL packets

[0204] - Mapping of reflective QoS flows to DRB for UL SDAP PDU

[0205] For SDAP layer devices, the UE can configure whether to use the SDAP layer device header or whether to use the SDAP layer device functionality for each PDCP layer device, each bearer, or each logical channel via RRC messages. If the SDAP header is configured, it can indicate the Non-Access Stratum (NAS) QoS reflection configuration 1-bit indicator (NAS reflective QoS) and the AS QoS reflection configuration 1-bit indicator (AS reflective QoS) in the SDAP header, allowing the UE to update or reconfigure the mapping information of uplink and downlink QoS flows and data bearers. The SDAP header can include QoS flow ID information indicating QoS. QoS information can be used as data processing priority information, scheduling information, etc., to smoothly support services.

[0206] The main functions of NR PDCP S30 or S65 may include some of the following functions.

[0207] - Header compression and decompression: ROHC only

[0208] - Transmission of user data

[0209] - Ordered delivery of upper-layer PDUs

[0210] - Unordered delivery of upper-layer PDUs

[0211] - PDCP PDU reordering for received PDUs

[0212] - Duplicate detection of lower-level SDUs

[0213] - PDCP SDU retransmission

[0214] - Encryption and decryption

[0215] - Timer-based SDU dropping in the uplink

[0216] In the aforementioned functions, reordering of the NR PDCP device refers to the function of reordering PDCP PDUs received from the lower layer in order based on the PDCP sequence number (SN), and may include the function of transmitting data to the upper layer in the reordered sequence. Alternatively, reordering of the NR PDCP device may include the following functions: transmitting data immediately regardless of order, recording PDCP PDUs lost as a result of reordering, reporting the status of lost PDCP PDUs to the transmitting side, and requesting retransmission of lost PDCP PDUs.

[0217] The main functions of NR RLC S35 or S60 may include some of the following functions.

[0218] - Transmission of upper-layer PDUs

[0219] - Ordered delivery of upper-layer PDUs

[0220] - Unordered delivery of upper-layer PDUs

[0221] - Error correction via ARQ

[0222] - Cascading, segmentation, and reassembly of RLC SDUs

[0223] - Resegmentation of RLC data PDUs

[0224] - Reordering of RLC data PDUs

[0225] - Duplicate Detection

[0226] - Protocol error detection

[0227] - RLC SDU discard

[0228] - RLC Reconstruction

[0229] In the aforementioned functions, the sequential delivery of NR RLC devices refers to the function of delivering RLC SDUs received from the lower layer to the upper layer in sequence. The sequential delivery of NR RLC devices may include the following functions: reassembling and delivering multiple received RLC SDUs segmented from an original RLC SDU; reordering received RLC SDUs with reference to the RLC sequence number (SN) or PDCP sequence number (SN); recording RLC PDUs lost as a result of reordering; reporting the status of lost RLC PDUs to the transmitter; and requesting retransmission of lost RLC PDUs. The sequential delivery of NR RLC devices may also include the following functions: if there are lost RLC SDUs, only RLC SDUs preceding the lost RLC SDU are delivered to the upper layer sequentially; and even if there are lost RLC SDUs, if a predetermined timer expires, all RLC SDUs received before the timer starts are delivered to the upper layer sequentially. Alternatively, in-order delivery of NR RLC devices may include the following functionality: despite the presence of lost RLC SDUs, if a predetermined timer has expired, all RLC SDUs received up to the present time will be delivered sequentially to the upper layer. Additionally, in-order delivery of NR RLC devices may include the following functionality: processing RLC PDUs in the order of receipt (regardless of sequence number order, in the order of arrival) and delivering them to the PDCP device, regardless of the order (out-of-order delivery); and in the case of segmentation, receiving segments stored in a buffer or to be received later, reconfiguring them into a complete RLC PDU, processing them, and delivering them to the PDCP device. The NR RLC layer may not include cascading functionality, which may be performed in the NR MAC layer or replaced by multiplexing functionality of the NR MAC layer.

[0230] In the above functions, the out-of-order delivery of NR RLC devices refers to the function of delivering RLC SDUs received from the lower layer to the upper layer in real time, regardless of the order. It may include the following functions: if a raw RLC SDU is received as a segment of multiple received RLC SDUs, then reassemble and deliver them; and store the RLC SN or PDCP SN of the received RLC PDUs and record any RLC PDUs lost as a result of reordering.

[0231] The NR MAC S40 or S55 can be connected to multiple NR RLC layer devices configured in a UE, and the main functions of the NR MAC may include some of the following functions.

[0232] - Mapping between logical channels and transport channels

[0233] - MAC SDU multiplexing / demultiplexing

[0234] - Scheduling Information Report

[0235] - Error correction via HARQ

[0236] Priority handling between logical channels of a UE

[0237] - Prioritize UEs through dynamic scheduling

[0238] - MBMS service identification

[0239] - Transmission format selection

[0240] - Fill

[0241] The NR PHY layer S45 or S50 can perform the following operations: channel coding and modulation of upper-layer data to obtain OFDM symbols and deliver them via a wireless channel; or demodulate OFDM symbols received via a wireless channel, channel decode them, and deliver them to the upper layer.

[0242] The detailed structure of a wireless protocol can vary depending on the carrier (or cell) operation scheme. For example, when a base station transmits data to a UE based on a single carrier (or cell), the base station and UE can use a protocol structure with a single structure for each layer, such as S00. On the other hand, when a base station transmits data to a UE based on carrier aggregation (CA) using multiple carriers in a single TRP, the base station and UE can use a protocol structure with a single structure up to RLC but multiplexing the PHY layer through the MAC layer, such as S10. As another example, when a base station transmits data to a UE based on dual connectivity (DC) using multiple carriers in multiple TRPs, the base station and UE can use a protocol structure with a single structure up to RLC but multiplexing the PHY layer through the MAC layer, such as S20.

[0243] Referring to the above description related to PDCCH and beam configuration, PDCCH retransmission is not supported in current Rel-15 and Rel-16 NR, and therefore, achieving the required reliability in scenarios requiring high reliability, such as URLLC, may be difficult. This disclosure provides a method for PDCCH retransmission via multiple transmit / receive points (TRPs). According to this disclosure, the PDCCH retransmission reliability of the UE can be improved. Specific methods will be described below through the following embodiments.

[0244] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Embodiments of the present disclosure can be applied to systems such as Frequency Division Duplex (FDD), Time Division Duplex (TDD), and Cross-Duplex (XDD), but are not limited thereto. As used herein, upper-layer signaling (or higher-layer signaling) can refer to a method or signal thereof for transmitting signals from a base station to a UE using a downlink data channel of the physical layer or from a UE to a base station using an uplink data channel of the physical layer. For example, upper-layer signaling (or higher-layer signaling) may also be referred to as “RRC signaling,” “PDCP signaling,” or “Media Access Control (MAC) control element (MAC CE),” but is not limited thereto.

[0245] In the following description, within this disclosure, the UE may use various methods to determine whether cooperative communication is applied. For example, the PDCCH to which cooperative communication is applied has a specific format, or the PDCCH to which cooperative communication is applied includes a specific indicator indicating whether cooperative communication is applied, or the PDCCH to which cooperative communication is applied is scrambled by a specific RNTI, or cooperative communication is assumed to be applied within a specific range indicated by the upper layer. In the following description, for ease of description, the Non-Coherent Joint Transmission (NC-JT) case may refer to the case where the UE receives a PDSCH to which cooperative communication is applied based on conditions similar to those described above. That is, the NC-JT case in this disclosure may include receiving a PDSCH to which cooperative communication is applied, and whether cooperative communication is applied can be identified based on at least one of the above conditions / methods or at least a combination thereof.

[0246] In the following text, determining the priority between A and B can be described differently, for example, by selecting the entity with higher priority and performing the corresponding operation according to a predetermined priority rule, or by omitting or discarding operations concerning the entity with lower priority.

[0247] The above examples can be described in several embodiments below, but these embodiments are not independent of each other, and one or more embodiments can be applied simultaneously or in combination.

[0248] In the following description, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this description, a base station is an entity that allocates resources to terminals and can be at least one of a gNode B, gNB, eNode B, eNB, Node B, base station (BS), radio access unit, base station controller, and nodes on a network. Terminals can include user equipment (UE), mobile station (MS), cellular phone, smartphone, computer, or multimedia system capable of performing communication functions. In the following description of embodiments of the present disclosure, 5G systems will be described as examples, but embodiments of the present disclosure can also be applied to other communication systems with similar technical backgrounds or channel types. Examples of such communication systems may include LTE or LTE-A mobile communication systems and mobile communication technologies developed after 5G. Therefore, based on the determination of those skilled in the art, embodiments of the present disclosure can also be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure. Embodiments of the present disclosure can be applied to FDD, TDD, or XDD systems, but are not limited thereto.

[0249] Furthermore, in describing this disclosure, a detailed description of a known function or configuration incorporated herein will be omitted where it is determined that such a description 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 custom. Therefore, the definitions of terms should be determined based on the content throughout the specification.

[0250] In the following description of this disclosure, upper-layer signaling may refer to signaling corresponding to at least one of the following signalings or a combination of one or more of the following signalings.

[0251] Master Information Block (MIB)

[0252] System Information Block (SIB) or SIB X (X=1, 2, ...)

[0253] Radio Resource Control (RRC)

[0254] Media Access Control (MAC) Control Element (CE)

[0255] Additionally, L1 signaling can refer to signaling corresponding to at least one signaling method or a combination of one or more of the following signaling methods that use physical layer channels or signaling.

[0256] Physical Downlink Control Channel (PDCCH)

[0257] Downlink Control Information (DCI)

[0258] UE-specific DCI

[0259] Group Public DCI

[0260] Public DCI

[0261] DCI scheduling (e.g., DCI used for scheduling downlink or uplink data).

[0262] Non-scheduled DCI (e.g., DCI not used for the purpose of scheduling downlink or uplink data).

[0263] Physical Uplink Control Channel (PUCCH)

[0264] Uplink Control Information (UCI)

[0265] [About MC-DCI]

[0266] In this disclosure, a DCI can be a single DCI or a single DCI format, and multiple DCIs can be multiple DCIs or multiple DCI formats. In this disclosure, a DCI can be a single PDCCH and / or can be transmitted or received through a single PDCCH, and multiple DCIs can be multiple PDCCHs and / or can be transmitted or received through multiple PDCCHs.

[0267] Typically, a UE receives a DCI (Distributed Cell Indicator), which may include scheduling information for a single cell. For example, in DCI format 0_0 / 0_1 / 0_2, a PUSCH can be scheduled for an uplink cell. Conversely, in DCI format 1_0 / 1_1 / 1_2, a PDSCH can be scheduled for a downlink cell. The scheduled cell can be indicated by the Carrier Indication Field (CIF) in the DCI format.

[0268] However, when scheduling PDSCH or PUSCH in each of multiple cells, this method requires sending and receiving multiple DCIs. Therefore, significant DCI overhead can occur. To reduce DCI overhead, a single DCI can schedule PDSCH and PUSCH in each of multiple cells. For convenience, this can be referred to as multi-cell DCI (MC-DCI). In this disclosure, MC-DCI can be a single DCI that schedules PDSCH and / or PUSCH in each of multiple cells. In this disclosure, the DCI scheduling PDSCH for each of multiple cells can be DCI format 1-3. Additionally, the DCI scheduling PUSCH for each of multiple cells can be DCI format 0-3.

[0269] Cells that can be scheduled by the MC-DCI can be configured by the upper layer. For example, assume that the MC-DCI can schedule (co-schedule) cells 0, 1, 2, and 3. After receiving the MC-DCI, the UE can receive the scheduling information for cells 0, 1, 2, and 3. That is, the UE can receive the scheduling information for cells 0, 1, 2, and 3 from the MC-DCI. For example, the upper layer can configure the MC-DCI to schedule cells 0, 1, 2, and 3. Here, the scheduling information may include Time Domain Resource Allocation (TDRA) information and / or Frequency Domain Resource Allocation (FDRA) information, through which data channels (downlink PDSCH and uplink PUSCH) are transmitted and received in each cell. Therefore, the UE can obtain the scheduling information for each cell through the MC-DCI and transmit and receive data channels from each cell.

[0270] There may be situations where the base station cannot schedule all the cells configured for the UE under certain circumstances. Specifically, there may be situations where the base station cannot schedule at least some of the multiple cells configured for the UE. For example, although the base station has configured four cells (e.g., cell 0, cell 1, cell 2, and cell 3) for scheduling via MC-DCI for the UE, some of these cells may be unschedulable due to scheduling for other UEs, poor channel conditions, or other reasons. In this case, the base station should be able to indicate to the UE which of the pre-configured cells scheduled via MC-DCI are being scheduled. In other words, the base station should be able to indicate to the UE one or more cells that are (actually) being scheduled out of the multiple cells scheduled via MC-DCI.

[0271] The UE can obtain information from the MC-DCI indicating cells co-scheduled by the MC-DCI among pre-configured cells (e.g., cell 0, cell 1, cell 2, and cell 3). In other words, among multiple cells configured to be scheduled via the MC-DCI, one or more cells co-scheduled via the MC-DCI can be identified based on the corresponding MC-DCI. More specifically, the base station can configure a table for the UE that includes co-scheduled cells. For example, rows in this table can have unique indexes. The index of each row (and / or each row) can include the index of the co-scheduled cells. For example, {cell 0, cell 1} can be configured for row 0, {cell 2, cell 3} can be configured for row 1, and {cell 0, cell 1, cell 2, cell 3} can be configured for row 2. Table 18 can be referred to as an example of a table configured for the UE.

[0272] [Table 18]

[0273] The UE can obtain the index value of the indication line from the MC-DCI. Therefore, the UE can determine the scheduled cell based on this value. For example, the MC-DCI may include information about the line index, and the UE can identify the scheduled cell based on the table and the line index obtained from the MC-DCI. For example, in the case of MC-DCI indication line 0, the UE can identify cells 0 and 1 as scheduled cells. For example, in the case of MC-DCI indication line 1, the UE can identify cells 2 and 3 as scheduled cells. For example, in the case of MC-DCI indication line 2, the UE can identify cells 0, 1, 2, and 3 as scheduled cells.

[0274] In this disclosure, a table can be configured to map the co-scheduled cells (or the index of the scheduled cells) to the index indicated by the DCI, and the scheduled cells can be identified based on the table and the index indicated by the DCI.

[0275] The UE can obtain information about the scheduled cell from the MC-DCI. The MC-DCI can include at least the following two types of DCI fields.

[0276] In the first type, information from a single DCI field is shared across multiple scheduled cells. For example, in the case of downlink allocation index, TPC commands for scheduled PUCCH, PUCCH resource indicators, or PDSCH to HARQ feedback timing indicator fields, information from a single DCI field can be shared across multiple scheduled cells.

[0277] In the second type, a DCI field may include blocks corresponding to multiple scheduled cells, and information from each block may be applied to the respective cell. For example, at least one of the Frequency Domain Resource Allocation (FDRA) field, Modulation and Coding Scheme (MCS) field, New Data Indicator (NDI) field, and HARQ process number field may be of the second type. If a DCI field of the second type includes multiple blocks, these blocks may have different lengths (payload sizes). For example, if the FDRA field includes a first block for a first cell and a second block for a second cell, the first and second blocks may have the same or different lengths. For example, the first block may have a length of 10 bits, and the second block may have a length of 5 bits. As an example, the FDRA field can be extended to DCI fields belonging to the second type.

[0278] The following shows an example of DCI format 0_3.

[0279]

[0280] [Regarding BWP changes]

[0281] The UE can receive the DCI format, including the Bandwidth Part Indicator field. The DCI format can be received during PDCCH monitoring of the currently active BWP. The Bandwidth Part Indicator field can indicate a BWP to be activated in the future (i.e., a new BWP to be activated after receiving the DCI including the Bandwidth Part Indicator field). Therefore, after receiving the DCI format, the UE activates the BWP indicated in the Bandwidth Part Indicator field. In other words, after receiving the DCI format, the UE can receive PDSCH or transmit PUSCH in the BWP indicated in the Bandwidth Part Indicator field. For ease of description below, the indicated BWP is referred to as the BWP indicated in the Bandwidth Part Indicator field.

[0282] For reference, each BWP is assigned / allocated / configured with its own unique index. The bandwidth portion indicator field can indicate the unique index.

[0283] In the following description, if the currently active BWP and the indicated BWP are different, the DCI format may be referred to as the DCI indicating a BWP switch. Additionally, the process of changing the currently active BWP to the indicated BWP may be referred to as a BWP switch (or BWP change).

[0284] For reference, in the case of MC-DCI, the Bandwidth Part Indicator field can indicate a single value for multiple cells. For example, when the Bandwidth Part Indicator field indicates "1", the BWP indicated for each of the multiple cells can be the BWP corresponding to "1". Therefore, in the case of MC-DCI, BWP handover can be indicated for multiple cells simultaneously.

[0285] When a UE receives a DCI indicating a handover, the UE can interpret the received DCI information based on the information in the indicated BWP. The process by which the UE interprets the received DCI information based on the indicated BWP is as follows.

[0286] - The UE can determine the length of each DCI field and the DCI length based on the information configured in the currently active BWP. The UE can then perform blind decoding of the PDCCH during the PDCCH monitoring time of the currently active BWP based on the determined length of the DCI. For convenience, the DCI field obtained here can be referred to as the received DCI field.

[0287] - The UE can determine the required DCI field length based on information configured in the indicated BWP. This length can be referred to as the required DCI field length. For reference, the length of the received DCI field (the DCI field length determined based on information configured in the currently active BWP) can be independent of the indicated BWP. That is, the length of the received DCI field can differ from the required DCI field length in the indicated BWP.

[0288] - If the received DCI field length is longer than the required DCI field length, the most significant bit (MSB) of the received DCI field can be removed to align with the required DCI field length. For example, suppose the received DCI field length is 10 bits and is [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9]. When the required DCI field length is 6 bits, the MSB of 4 bits can be excluded, and the DCI field can be interpreted using the remaining 6 bits [b4, b5, b6, b7, b8, b9]. This process can be called truncation.

[0289] - If the received DCI field length is shorter than the required DCI field length, you can add "0"s to the most significant bit (MSB) of the received DCI field to align it with the required DCI field length. For example, suppose the received DCI field length is 10 bits and is [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9]. When the required DCI field length is 2 bits, add 2 "00"s to the MSB, and the DCI field can be interpreted using 12 bits [0, 0, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9].

[0290] This series of processes can be referred to as DCI field length alignment (DCI field size alignment).

[0291] This disclosure describes a method for performing DCI field length alignment in MC-DCI. More specifically, the DCI field in MC-DCI can be a second-type DCI field. That is, each DCI field can include multiple blocks. Each block can correspond to each cell to be scheduled.

[0292] In this disclosure, DCI field length alignment can be performed using the following two methods.

[0293] As a first method, the UE can apply the aforementioned DCI field length alignment to each block. This method can be referred to as block-level length alignment or "per-block" length alignment. More specifically, - The UE can determine the length of each DCI field and the DCI length based on the information configured in the currently active BWP. The UE can then perform blind decoding of the PDCCH during PDCCH monitoring in the currently active BWP based on the DCI length. For convenience, the DCI field obtained here can be referred to as the received DCI field. The received DCI field may include multiple blocks. The length of each of the multiple blocks included in the received DCI field can be determined.

[0294] - The UE can determine the length of the required DCI field based on information configured in the indicated BWP. This length can be referred to as the required DCI field length. For reference, the length of the received DCI field may be independent of the indicated BWP. That is, the length of the received DCI field may differ from the length of the required DCI field in the indicated BWP. For reference, the required DCI field may include multiple blocks. Furthermore, the length of each of the multiple blocks included in the required DCI field can be determined.

[0295] - If the length of the block in the received DCI field is longer than the length of the block in the required DCI field, the most significant bit (MSB) of the block in the received DCI field can be removed to align with the length of the block in the required DCI field. If the received DCI field includes multiple blocks, the length can be aligned for each block.

[0296] - If the length of the block in the received DCI field is shorter than the length of the block in the required DCI field, a "0" can be added to the most significant bit (MSB) of the block in the received DCI field to align it with the length of the block in the required DCI field.

[0297] - Figure 11 A is a diagram illustrating an example. (Reference) Figure 11 A. Assume the received DCI field consists of two blocks. Each block is 10 bits long. That is, the received DCI field is 20 bits long. Let it be [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15, b16, b17, b18, b19]. The first 10 bits correspond to the first block, and the last 10 bits correspond to the second block. Assume the required DCI field includes a first block of 12 bits and a second block of 5 bits. That is, the required DCI field may require a total of 17 bits.

[0298] - The UE can align the first block length. The first block length of the received DCI field is 10 bits, and the first block length of the required DCI field is 12 bits. Therefore, two "0,0" bits can be added to the MSB of the first block of the received DCI field. Thus, the first block of the required DCI field can be [0,0,b0,b1,b2,b3,b4,b5,b6,b7,b8,b9]. The UE can align the second block length. The second block length of the received DCI field is 10 bits, and the second block length of the required DCI field is 5 bits. Therefore, 5 bits can be removed from the MSB of the second block of the received DCI field. Thus, the second block of the required DCI field can be [b15,b16,b17,b18,b19].

[0299] - Figure 12 A is a diagram illustrating an example. (Reference) Figure 12A. Assume the received DCI field consists of two blocks. Each block is 5 bits long. That is, the received DCI field length is 10 bits. Assume it is [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9]. The first 5 bits correspond to the first block, and the last 5 bits correspond to the second block. Assume the required DCI field includes a 10-bit first block and a 10-bit second block. That is, the required DCI field may require a total of 20 bits.

[0300] - The UE can align the first block length. The first block length of the received DCI field is 5 bits, and the first block length of the required DCI field is 10 bits. Therefore, 5 bits "0,0,0,0,0,0" can be added to the MSB of the first block of the received DCI field. Thus, the first block of the required DCI field can be [0,0,0,0,0,b0,b1,b2,b3,b4]. The UE can align the second block length. The second block length of the received DCI field is 5 bits, and the second block length of the required DCI field is 10 bits. Therefore, 5 bits "0,0,0,0,0,0" can be added to the MSB of the second block of the received DCI field. Thus, the second block of the required DCI field can be [0,0,0,0,0,b5,b6,b7,b8,b9].

[0301] As a second method, the UE can use the DCI field length alignment described above. This method can be referred to as field-level length alignment or "per-field" length alignment. More specifically, - The UE can determine the length of each DCI field and the DCI length based on the information configured in the currently active BWP. The UE can then perform blind decoding of the PDCCH during PDCCH monitoring in the currently active BWP based on the DCI length. For convenience, the DCI field obtained here can be referred to as the received DCI field. The received DCI field may include multiple blocks. The length of each of the multiple blocks included in the received DCI field can be determined.

[0302] - The UE can determine the length of the required DCI field based on information configured in the indicated BWP. This length can be referred to as the required DCI field length. For reference, the length of the received DCI field may be independent of the indicated BWP. That is, the length of the received DCI field may differ from the length of the required DCI field in the indicated BWP. For reference, the required DCI field may include multiple blocks. Furthermore, the length of each of the multiple blocks included in the required DCI field can be determined.

[0303] - If the length of the received DCI field is longer than the required DCI field length, the most significant bit (MSB) of the received DCI field can be removed to align with the required DCI field length. In this case, the length of each block included in the received DCI field and the length of each block included in the required DCI field can be disregarded.

[0304] - Figure 11 B is a diagram illustrating an example. (Reference) Figure 11 B. Assume the received DCI field consists of two blocks. Each block is 10 bits long. That is, the received DCI field is 20 bits long. Let it be [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15, b16, b17, b18, b19]. The first 10 bits correspond to the first block, and the last 10 bits correspond to the second block. Assume the required DCI field includes a first block of 12 bits and a second block of 5 bits. That is, the required DCI field may require a total of 17 bits. Therefore, the UE can remove the MSB 3 bits of the received DCI field to obtain 17 bits [b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15, b16, b17, b18, b19]. Additionally, 12 bits [b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14] can be used for the first block interpretation, and 5 bits [b15, b16, b17, b18, b19] can be used for the second block interpretation.

[0305] - If the length of the received DCI field is shorter than the required DCI field length, a "0" can be added to the most significant bit (MSB) of the received DCI field to align it with the required DCI field length. In this case, the length of each block included in the received DCI field and the length of each block included in the required DCI field can be disregarded.

[0306] - Figure 12 B is a diagram illustrating an example. (Reference) Figure 12B. Assume the received DCI field consists of two blocks. Assume each block is 5 bits. That is, the received DCI field length is 10 bits. Assume it is [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9]. The first 5 bits correspond to the first block, and the last 5 bits correspond to the second block. Assume the required DCI field includes a first block length of 10 bits and a second block length of 10 bits. That is, the required DCI field may require a total of 20 bits. Therefore, the UE can add 10 bits "0, 0, 0, 0, 0, 0, 0, 0, 0, 0" to the MSB of the received DCI field to obtain 20 bits [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9]. Additionally, the first 10 bits [0, 0, 0, 0, 0, 0, 0, 0, 0] can be used for the first block interpretation, and the last 10 bits [b1, b2, b3, b4, b5, b6, b7, b8, b9] can be used for the second block interpretation.

[0307] The UE can be configured by the base station using one of the first or second methods. That is, the base station's higher-layer signals can be configured with MC-DCI, and the UE can also be configured by the base station using one of the first or second methods. The UE can use one of the first or second methods according to the configured method. The UE can align the length of each DCI field based on the configured method. Furthermore, the DCI fields can be interpreted. Based on the interpretation, the UE can receive PDSCH or send PUSCH in the BWP indicating multiple cells.

[0308] For reference, the UE can be configured with one of the first and second methods for all DCI fields. Alternatively, the UE can be configured with one of the first and second methods for each DCI field. That is, the first DCI field can be configured using the first method, and the second DCI field can be configured using the second method.

[0309] For reference, the UE can change the configuration of one of the first and second methods for all BWPs. Alternatively, the UE can configure one of the first and second methods based on the currently active BWP. That is, when the currently active BWP is BWP#1, the first method can be configured, and when the currently active BWP is BWP#2, the second method can be configured.

[0310] For reference, the UE can change the configuration of one of the first and second methods for all BWPs. Alternatively, the UE can configure one of the first and second methods according to the indicated BWP. That is, when the indicated BWP is BWP#1, the first method can be configured, and when the indicated BWP is BWP#2, the second method can be configured.

[0311] For reference, the UE can change the configuration of one of the first and second methods for all BWPs. Alternatively, the UE can configure one of the first and second methods based on the combination of the currently active BWP and the indicated BWP. That is, when the currently active BWP is BWP#1 and the indicated BWP is BWP#2, the first method can be configured, and when the currently active BWP is BWP#2 and the indicated BWP is BWP#1, the second method can be configured.

[0312] In the examples above, BWP#1 and BWP#2 are merely examples, and the same ideas of this disclosure can be applied to other BWPs.

[0313] This process is in Figure 13 The flowchart is shown.

[0314] In this disclosure, the UE can optionally use one of the first to second methods without separate configuration. (See reference) Figures 11 to 12 The following can be observed.

[0315] - refer to Figure 11 The received DCI field length is 20 bits, and the required DCI field length is 17 bits. However, in the first method, 15 bits out of the 20 bits can be used. Additionally, two "0,0" bits can be added to define the 17 bits. In the second method, 17 bits out of the 20 bits can also be used. Therefore, the first method is inefficient in terms of bit usage. That is, the second method may be more efficient when the received DCI field length is equal to or longer than the required DCI field length.

[0316] - refer to Figure 12 The received DCI field is 10 bits long, and the required DCI field length is 20 bits. In the second method, all bits in the first block may be "0". However, in the first method, the first and second blocks can each contain 5 bits. That is, the first method may be more efficient when the received DCI field length is shorter than the required DCI field length.

[0317] Based on the above observations, in the embodiments of this disclosure, the UE can determine the first method and the second method as follows.

[0318] The UE can configure the MC-DCI by the base station. When the UE receives an MC-DCI indicating a change in the BWP, for each DCI field, the UE can determine the received DCI field length and the required DCI field length. The received DCI field length is determined based on the configuration configured in the BWP (or BWP pair) that monitors the MC-DCI by including the DCI field lengths in the received MC-DCI. The required DCI field length is determined based on the configuration configured in the indicated BWP (or BWP pair). The UE can select one of a first method and a second method for each DCI field based on the received DCI field length and the required DCI field length.

[0319] For example, when the length of the received DCI field is equal to or longer than the required DCI field length, the UE can choose the second method. When the length of the received DCI field is shorter than the required DCI field length, the UE can choose the first method.

[0320] For example, when the length of the received DCI field is longer than the required DCI field length, the UE can choose the second method. When the length of the received DCI field is shorter than the required DCI field length, the UE can choose the first method. When the length of the received DCI field is equal to the required DCI field length, separate length alignment is not required.

[0321] For example, when the length of the received DCI field is equal to or longer than the required DCI field length, the UE can choose the second method. When the length of the received DCI field is shorter than the required DCI field length, the UE can be configured by the base station to use both the first and second methods. That is, the UE can be configured by the base station via higher-layer signals (RRC signals). When the length of the received DCI field is shorter than the required DCI field length, the configured method can be used.

[0322] The UE can perform DCI field length alignment for each DCI field based on a defined method. Additionally, the UE can interpret the DCI fields. The UE can then perform PDSCH reception or PUSCH transmission in the instruction BWP of multiple cells based on the interpretation.

[0323] This process is in Figure 14 The flowchart is shown.

[0324] and Figure 14 The corresponding UE operations are shown in the table below.

[0325]

[0326] Figure 15 Another example considered in this disclosure is shown.

[0327] Figure 15 The received DCI field can include two blocks. The first block of the received DCI field can be 5 bits long, and the second block can be 5 bits long. Therefore, the total length of the received DCI field can be 10 bits. The required DCI field can also include two blocks. The first block of the received DCI field can be 10 bits long, and the second block can be 3 bits long. Therefore, the total length of the required DCI field can be 13 bits.

[0328] Figure 15 A illustrates the DCI field length alignment according to the first method. The first block can add 5 bits "0,0,0,0,0" to the MSB, and the second block can exclude 2 bits from the MSB. Therefore, according to the first method, the UE can use only 8 bits of the 10 bits included in the received DCI field.

[0329] Figure 15 A illustrates DCI field length alignment according to the second method. Three "0,0,0" bits can be added to the MSB of the received DCI field, thus determining the required 13 bits of the DCI field. Of these 13 bits, the first 10 bits can correspond to the first block, and the last 3 bits can correspond to the second block. Therefore, the three "0,0,0" bits can be included in the 10 bits of the first block. According to the second method, the UE can use all 10 bits included in the received DCI field.

[0330] Therefore, from the perspective of bit usage efficiency of the received DCI field, the second method may be a better approach.

[0331] As an embodiment of this disclosure, the UE may select a method for maximizing bit usage efficiency.

[0332] The UE can be configured with MC-DCI by the base station. When the UE receives an MC-DCI indicating a change in the BWP, for each DCI field, the UE can determine the length of the received DCI field and the required DCI field length. The length of the received DCI field is determined based on the configuration configured in the BWP (or BWP pair) that monitors the MC-DCI by including the length of the DCI fields in the received MC-DCI. The required DCI field length is determined based on the configuration configured in the indicated BWP (or BWP pair).

[0333] The UE can determine the number of bits included in the desired DCI field from the received DCI field using a first method. That is, it can determine the number of bits used for interpretation from the received DCI field. The UE can also determine the number of bits included in the desired DCI field from the received DCI field using a second method. That is, it can determine the number of bits used for interpretation from the received DCI field.

[0334] The UE can determine one method based on the number of bits according to the first method and the number of bits according to the second method. Here, a method corresponding to the number of bits can be selected. For example, when the number of bits according to the first method is greater than the number of bits according to the second method, the first method can be selected. For reference, when both methods have the same number of bits, the UE can determine one of the first method to the second method as the other method. Here, the other method can be a determined method (e.g., the second method) or a method configured by higher-layer signals.

[0335] The UE can perform DCI field length alignment for each DCI field based on a defined method. Additionally, the UE can interpret the DCI fields. The UE can then perform PDSCH reception or PUSCH transmission in the instruction BWP of multiple cells based on the interpretation.

[0336] This process is in Figure 16 The flowchart is shown.

[0337] In the foregoing embodiments, the UE maximizes the bit utilization efficiency of the received DCI field. (See reference...) Figure 15 The UE can choose the second method. However, refer to Figure 15 B. The UE can recognize that "0" is only added to one block. That is, although the bit usage efficiency of the received DCI field is maximized, there may be differences between blocks.

[0338] Another embodiment of this disclosure is a method for distributing bits evenly to each block while maximizing bit utilization efficiency of the received DCI field.

[0339] The UE can determine the length of the received DCI field. This length can be referred to as L. For reference, the received DCI field may include multiple blocks. Assume it includes N blocks. Assume the lengths of each block are L_1, L_2, ..., L_N. Here, L_1 + L_2 + ... + L_N = L.

[0340] The UE can determine the length of the required DCI field. This length can be referred to as R. For reference, the received DCI field can include multiple blocks. Assume there are N blocks. Assume the lengths of each block are R_1, R_2, ..., R_N. Here, R_1 + R_2 + ... + R_N = R.

[0341] The UE can change the length of the blocks in the received DCI field to be proportional to the length of the blocks in the desired DCI field. Assume the lengths of the blocks in the received DCI field are S_1, S_2, ..., S_N. S_1 + S_2 + ... + S_N = L. To make it proportional to the length of the blocks in the desired DCI field, S_i can be obtained as follows.

[0342] S_i = f(L (R_i / R)), i=1、……、N-1

[0343] S_N = L-(S_1+S_2+……S_{N-1})

[0344] Here, f(x) can be one of ceil(x), floor(x), and round(x). ceil(x) is the floor function, floor(x) is the floor function, and round(x) is the rounding function.

[0345] refer to Figure 17 This is an example where L=10, R_1=10, and R_2=3. The UE can calculate S_1 = ceil(L... R_1 / R) = ceil(10 10 / 13) = 8, S_2 = L - S_1 = 2. That is, although the 10 bits of the received DCI field consist of 5 bits from the first block and 5 bits from the second block, the UE can assume that the 10 bits of the received DCI field consist of 8 bits from the first block and 2 bits from the second block for DCI field length alignment. Furthermore, since the first block of the required DCI field is 10 bits, 2 bits of "0,0" can be added to the first block (8 bits) of the received DCI field. Since the second block of the required DCI field is 3 bits, 1 bit of "0" can be added to the second block (2 bits) of the second block (2 bits) of the received DCI field. Therefore, according to embodiments of this disclosure, the UE can use all 10 bits of the received DCI field and can similarly add "0" to the blocks.

[0346] As another method disclosed herein, the UE can minimize the number of blocks with added "0". If "0" is added to a block via DCI field length alignment, a fixed bit value is added to that block. Therefore, the base station may be unable to perform free indication. This method is used to correctly indicate information for as many blocks as possible.

[0347] The UE can determine the length of the received DCI field. This length can be referred to as L. For reference, the received DCI field may include multiple blocks. Assume it includes N blocks. Assume the lengths of each block are L_1, L_2, ..., L_N. Here, L_1 + L_2 + ... + L_N = L.

[0348] The UE can determine the required length of the DCI field. This length can be referred to as R. For reference, the received DCI field can include multiple blocks. Assume there are N blocks. Assume the lengths of each block are R_1, R_2, ..., R_N. Here, R_1 + R_2 + ... + R_N = R.

[0349] The UE can change the length of the blocks in the received DCI field to be proportional to the length of the blocks in the desired DCI field. Assume the lengths of the blocks in the received DCI field are S_1, S_2, ..., S_N. S_1 + S_2 + ... + S_N = L. To make it proportional to the length of the blocks in the desired DCI field, S_i can be obtained as follows.

[0350] If R_1 If L, then S_1 = R_1. If S_1 + R_2 If L, then S_2 = R_2. Additionally, if S_1 + S_2 + ... + S_{k-1} + R_k If L, then S_k = R_k. If S_1 + S_2 + ... + S_{k-1} + R_k If L is a given block index, then S_k = L - (S_1 + S_2 + ... + S_{k-1}) and S_{k+1} = S_{k+2} = ... + S_N = 0. In other words, the required number of bits can be allocated in ascending order of the block index.

[0351] In this disclosure, ascending order of the block index is used. The block index can be determined according to the order in which they are included in the DCI field. Alternatively, the block index can be determined based on the length of the blocks included in the DCI field. For example, blocks with shorter lengths can have lower indices, and blocks with longer lengths can have higher indices. When using this method, bits can be preferentially allocated to shorter-length blocks, and the number of blocks without added "0"s can be maximized.

[0352] In another embodiment of this disclosure, the UE may preferentially allocate bits to the block corresponding to a cell (or a predetermined number of cells), thereby preventing "0"s from being added to the block corresponding to that cell. This can be possible when one cell (or a predetermined number of cells) plays a more important role than other cells. For example, a cell may be a cell used for monitoring PDCCH, a Pcell, or a cell used for transmitting PUCCH. Alternatively, it may be the cell with the lowest cell index.

[0353] Another embodiment of this disclosure relates to the case where a block in the FDRA field corresponds to all the "0"s added via DCI field length alignment. Reference Figure 12B, the first block can be [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], and all the "0"s here can be "0"s added by aligning the DCI field length. In this case, the UE can perform the following operations.

[0354] The UE may assume that there is no PDSCH (or PUSCH) scheduled based on the FDRA field. In other words, the UE may choose not to receive the PDSCH (or PUSCH) in the cell corresponding to the first block. This is independent of the FDRA type configured for the UE.

[0355] In another approach, the UE can treat the above situation as an error. That is, the base station may not configure the UE with all bits set to "0". Upon receiving a DCI indicating the above operation, the UE may discard the DCI. The UE may not execute the operation indicated by the discarded DCI.

[0356] The UE can configure or determine the number of blocks corresponding to the cell's BWP index from the base station. More specifically, for each cell, the UE can be configured with one or more BWPs, and each BWP can have a unique index. The unique index can be one of 1, 2, 3, and 4. For example, cell A (or cell #A) can be configured with two BWPs, and these two BWPs can have indices 1 and 2; cell B (or cell #B) can be configured with two BWPs, and these three BWPs can have indices 1, 2, and 3; cell C (or cell #C) can be configured with two BWPs, and these two BWPs can have indices 1 and 2; and cell D (or cell #D) can be configured with four BWPs, and these four BWPs can have indices 1, 2, 3, and 4.

[0357] Each BWP in each cell can include different higher-layer configurations. The UE can determine the DCI format length or the length of fields included in the DCI format based on the higher-layer configuration. For example, maxNrofCodeWordsScheduledByDCI can be configured as higher-layer configuration information used to configure the number of transport blocks in a BWP of a cell. When maxNrofCodeWordsScheduledByDCI is configured to 2, the UE can determine that the PDSCH scheduled by the DCI format in the cell's BWP can include up to two transport blocks. Therefore, the DCI fields in the DCI format corresponding to the cell's BWP can include the modulation and coding scheme (MCS) value, new data indicator (NDI) value, and redundancy value (RV) of the first transport block, and the MCS value, NDI value, and RV value of the second transport block. If maxNrofCodeWordsScheduledByDCI is not configured to 2 in a BWP of a cell, the UE can determine that the DCI format can schedule up to one transport block in the cell's BWP. Therefore, the DCI field corresponding to the BWP of the cell in the DCI format may include the modulation and coding scheme (MCS) value, new data indicator (NDI) value, and redundancy value (RV) of the first transport block, but may not include the MCS value, NDI value, and RV value of the second transport block.

[0358] When a UE monitors the DCI format of PDSCH scheduling in multiple cells, it can determine the length of the DCI format or the length of the DCI fields included in the DCI format based on the BWPs that have been activated in each cell. That is, the BWPs that have been activated in cells A (cell #A) to D (cell #D) can be BWPs with index 1.

[0359] The DCI format for scheduling PDSCH across multiple cells can include a single BWP index. For example, the DCI format could indicate 1 as the BWP index value. In this case, the DCI format can schedule PDSCH in BWPs with a BWP index of 1 in multiple cells, thus scheduling PDSCH across multiple cells. If there is no BWP corresponding to the index in a cell, the UE can schedule PDSCH in an already activated BWP in that cell that does not correspond to the index.

[0360] When the DCI format of the PDSCH is scheduled across multiple cells, indicating a BWP other than the already activated BWP, the UE may have different required DCI field lengths. More specifically, the length of the DCI field determined by the higher-layer configuration of the activated BWP can be a first length, and the length of the DCI field determined by the higher-layer configuration of the indicated BWP can be a second length. The UE can obtain a DCI field of the first length from the DCI format, but since the BWP scheduling the PDSCH is the indicated BWP, a DCI field of the second length may be required. For this purpose, UE operations are defined as shown in Table 19.

[0361] [Table 19]

[0362] Referring to Table 19, when the first length is longer than the second length, the UE can interpret the DCI field by using only the first length of the DCI field with the first length. When the first length is shorter than the second length, the UE can interpret the DCI field by padding the most significant bit (MSB) of the DCI field with the first length with "0"s to obtain the first length.

[0363] Referring to Table 19, when the DCI field comprises multiple blocks, the above operations can be performed on each block. In the following description, performing the above operations on each block can be referred to as block-based DCI field length alignment. Specific methods for performing the above operations on each block are proposed in this disclosure.

[0364] In the following description, the DCI field may be included in the DCI format of the PDSCH in scheduling multiple cells, and may include at least one block.

[0365] The DCI field corresponding to an active BWP in the cell may include a first number of blocks, and the DCI field corresponding to an indicated BWP in the cell may include a second number of blocks. The first number and the second number may be the same as or different from each other.

[0366] For ease of description, assume that the first number (N1) of blocks corresponding to the active BWP are {active block #1, active block #2, ..., active block #N1}, and assume that the second number (N2) of blocks corresponding to the indicated BWP are {indicator block #1, indicator block #2, ..., indicator block #N2}. Here, active block #X represents the block with index X. X can have one of the block number (N1) values ​​starting from 1. Indicator block #Y represents the block with index Y. Y can have one of the block number (N2) values ​​starting from 1. The block indices in the DCI field can be determined in ascending order.

[0367] The first and second numbers can be the same, but the cells corresponding to the first number of blocks can be different from those corresponding to the second number of blocks. More specifically, assume the first and second numbers are 3. The three blocks included in the DCI field corresponding to an already activated BWP in a cell can be blocks corresponding to cells A, C, and D (active block #1 corresponds to cell A, active block #2 corresponds to cell C, and active block #3 corresponds to cell D). However, the three blocks included in the DCI field corresponding to an indicated BWP in a cell can be blocks corresponding to cells A, B, and C (indication block #1 corresponds to cell A, indication block #2 corresponds to cell B, and indication block #3 corresponds to cell C).

[0368] The UE can perform DCI field length alignment for each block, as follows.

[0369] As a first method, the UE can perform DCI field length alignment for each block based on blocks with the same block index (active block #X and indicator block #Y, X=Y).

[0370] - The length of active block #1 can be considered as a first length, and the length of indicator block #1 can be considered as a second length, so that the first length can be aligned with the second length.

[0371] - The length of active block #2 can be considered as the first length, and the length of indicator block #2 can be considered as the second length, so that the first length can be aligned with the second length.

[0372] - The length of active block #3 can be considered as the first length, and the length of indicator block #3 can be considered as the second length, so that the first length can be aligned with the second length.

[0373] As a second method, the UE can perform DCI field length alignment for each block based on blocks with the same cell index corresponding to the cell (active block #X and indication block #Y, where the cell index corresponding to active block #X and the cell index corresponding to indication block #Y are the same). For reference, the DCI field may not include blocks corresponding to a specific cell. For example, the DCI field corresponding to an activated BWP in a cell may include blocks corresponding to cells A, C, and D (active block #1 corresponds to cell A, active block #2 corresponds to cell C, and active block #3 corresponds to cell D), but may not include the block corresponding to cell B. The DCI field corresponding to an indicated BWP in a cell may include blocks corresponding to cells A, B, and C (indication block #1 corresponds to cell A, indication block #2 corresponds to cell B, and indication block #3 corresponds to cell C), but may not include the block corresponding to cell D. According to this disclosure, the length of an excluded block may be considered as 0 bits.

[0374] - The length of the active block #1 corresponding to cell A can be regarded as the first length, and the length of the indicator block #1 can be regarded as the second length, so that the first length can be aligned with the second length.

[0375] Since there is no block corresponding to cell B in the blocks {active block #1, active block #2 and active block #3} corresponding to the already activated BWP, the first length can be regarded as 0 bits, and the indicator block #2 can be regarded as the second length, so that the first length can be aligned with the second length.

[0376] - The length of the active block #2 corresponding to cell C can be regarded as the first length, and the length of the indicator block #3 can be regarded as the second length, so that the first length can be aligned with the second length.

[0377] - The length of the active block #1 corresponding to cell D can be regarded as the first length, and since there is no block corresponding to cell D in the blocks {indicator block #1, indicator block #2 and indicator block #3} corresponding to the indicated BWP, the second length can be regarded as 0 bits, so that the first length can be aligned with the second length.

[0378] When the first quantity differs from the second quantity, the cell corresponding to the first quantity of blocks can be different from the cell corresponding to the second quantity of blocks. Let the first quantity be 3 and the second quantity be 4. The three blocks included in the DCI field corresponding to an already activated BWP in a cell can be blocks corresponding to cells A, C, and D (active block #1 corresponds to cell A, active block #2 corresponds to cell C, and active block #3 corresponds to cell D). However, the four blocks included in the DCI field corresponding to an indicated BWP in a cell can be blocks corresponding to cells A, B, C, and D (indicator block #1 corresponds to cell A, indicator block #2 corresponds to cell B, indicator block #3 corresponds to cell C, and indicator block #4 corresponds to cell D).

[0379] The UE can perform DCI field length alignment for each block, as follows.

[0380] As a first method, the UE can perform DCI field length alignment for each block based on blocks with the same block index (active block #X and indicator block #Y, X=Y). If a block with a specific index is not included in the DCI field, the UE can treat the length of that block as 0 bits.

[0381] - The length of active block #1 can be considered as a first length, and the length of indicator block #1 can be considered as a second length, so that the first length can be aligned with the second length.

[0382] - The length of active block #2 can be considered as the first length, and the length of indicator block #2 can be considered as the second length, so that the first length can be aligned with the second length.

[0383] - The length of active block #3 can be considered as the first length, and the length of indicator block #3 can be considered as the second length, so that the first length can be aligned with the second length.

[0384] - The length of active block #4 can be considered as the first length, and the length of indicator block #4 can be considered as the second length, so that the first length can be aligned with the second length. Here, since the DCI field does not include indicator block #4, indicator block #4 can be considered as bit 0.

[0385] As a second method, the UE can perform DCI field length alignment for each block based on blocks with the same cell index corresponding to the cell (active block #X and indicator block #Y, where the cell index corresponding to active block #X and the cell index corresponding to indicator block #Y are the same). For reference, the DCI field may not include blocks corresponding to a specific cell. For example, the DCI field corresponding to a BWP that is already active in a cell may include blocks corresponding to cells A, C, and D (active block #1 corresponds to cell A, active block #2 corresponds to cell C, and active block #3 corresponds to cell D), but may not include the block corresponding to cell B.

[0386] - The length of the active block #1 corresponding to cell A can be regarded as the first length, and the length of the indicator block #1 can be regarded as the second length, so that the first length can be aligned with the second length.

[0387] Since there is no block corresponding to cell B in the blocks {active block #1, active block #2 and active block #3} corresponding to the already activated BWP, the first length can be regarded as 0 bits, and the indicator block #2 can be regarded as the second length, so that the first length can be aligned with the second length.

[0388] - The length of the active block #2 corresponding to cell C can be regarded as the first length, and the length of the indicator block #3 can be regarded as the second length, so that the first length can be aligned with the second length.

[0389] - The length of the active block #3 corresponding to cell D can be regarded as the first length, and the length of the indicator block #3 can be regarded as the second length, so that the first length can be aligned with the second length.

[0390] Table 20 illustrates the operation of the UE according to Method 1. Compared to Table 19, Table 20 shows that when performing DCI field length alignment for each block, the UE can perform length alignment for blocks with the same index based on the block index.

[0391] [Table 20]

[0392] Table 21 illustrates the UE's operation according to Method 2. Compared to Table 19, Table 21 shows that when performing DCI field length alignment for each block, the UE can perform length alignment for blocks with the same index based on the cell index corresponding to the block.

[0393] [Table 21]

[0394] Figure 18 The structure of a UE in a wireless communication system according to an embodiment of the present disclosure is shown.

[0395] refer to Figure 18 The UE may include transceivers (which collectively refer to UE receiver 1800 and UE transmitter 1810), memory (not shown), and UE processor 1805 (or UE controller or processor). UE transceivers 1800 and 1810, memory, and UE processor 1805 can operate according to the communication methods described above for the UE. However, the components of the UE are not limited to the examples described above. For example, the UE may include more or fewer components than those described above. Furthermore, the transceiver, memory, and processor may be implemented as a single chip.

[0396] A transceiver can transmit / receive signals with a base station. These signals may include control information and data. For this purpose, a transceiver may include an RF transmitter configured to up-convert and amplify the frequency of the transmitted signal, an RF receiver configured to perform low-noise amplification and down-convert the frequency of the received signal, and so on. However, this is only one embodiment of a transceiver, and the components of a transceiver are not limited to RF transmitters and RF receivers.

[0397] In addition, the transceiver can receive signals, output signals to the processor, and transmit signals output from the processor via the wireless channel.

[0398] The memory can store programs and data required for the operation of the UE. Additionally, the memory can store control information or data included in signals sent / received by the UE. The memory can include storage media (such as ROM, RAM, hard disk, CD-ROM, and DVD) or a combination of storage media. Furthermore, the memory can include multiple memories.

[0399] Furthermore, the processor can control a series of processes that enable the UE to operate according to the above embodiments. For example, the processor can control the UE's components to receive DCIs configured in two layers to receive multiple PDSCHs simultaneously. The processor may include multiple processors, and the processor can perform operations controlling the UE's components by executing programs stored in memory.

[0400] Figure 19 The structure of a base station in a wireless communication system according to an embodiment of the present disclosure is shown.

[0401] refer to Figure 19 A base station may include transceivers (which collectively refer to base station receiver 1900 and base station transmitter 1910), memory (not shown), and base station processor 1905 (or base station controller or processor). The base station transceivers 1900 and 1910, the memory, and the base station processor 1905 may operate according to the communication methods described above for the base station. However, the components of a base station are not limited to the examples described above. For example, a base station may include more or fewer components than those described above. Furthermore, the transceiver, memory, and processor may be implemented as a single chip.

[0402] A transceiver can transmit / receive signals with a UE. These signals may include control information and data. For this purpose, a transceiver may include an RF transmitter configured to up-convert and amplify the frequency of the transmitted signal, an RF receiver configured to perform low-noise amplification and down-convert the frequency of the received signal, and so on. However, this is only one embodiment of a transceiver, and the components of the transceiver are not limited to RF transmitters and RF receivers.

[0403] In addition, the transceiver can receive signals, output signals to the processor, and transmit signals output from the processor via the wireless channel.

[0404] The memory can store programs and data required for the operation of the base station. Additionally, the memory can store control information or data included in signals transmitted / received by the base station. The memory can include storage media (such as ROM, RAM, hard disk, CD-ROM, and DVD) or a combination of storage media. Furthermore, the memory can include multiple memories.

[0405] The processor can control a series of processes that enable the base station to operate according to the embodiments of the present disclosure described above. For example, the processor can control components of the base station to configure DCIs in two layers, including allocation information regarding multiple PDSCHs, and transmit the configured DCIs. The processor may include multiple processors, and the processor can perform operations controlling the components of the base station by executing programs stored in memory.

[0406] The methods disclosed in the claims or the methods of the embodiments described in this disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0407] When the method is implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors within an electronic device. At least one program includes instructions that cause the electronic device to perform the method as defined by the appended claims and / or as disclosed herein, according to various embodiments of this disclosure.

[0408] These programs (software modules or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), disk storage devices, optical disc ROM (CD-ROM), digital versatile optical disc (DVD) or other types of optical storage devices, or magnetic tape cassettes. Alternatively, any combination of some or all of them can form the memory in which the programs are stored. Furthermore, an electronic device may include multiple such memories.

[0409] Furthermore, the program can be stored on an attachable storage device that can be accessed by the electronic device via a communication network such as the Internet, intranet, local area network (LAN), wide area network (WLAN), and storage area network (SAN), or a combination thereof. Such storage devices can access the electronic device via an external port. Additionally, a separate storage device on a communication network can access portable electronic devices.

[0410] In the detailed embodiments described above, elements included in this disclosure are represented in a singular or plural form according to the presented embodiments. However, for ease of description, the singular or plural form is suitably chosen for the presented situation, and this disclosure is not limited to elements represented in a singular or plural form. Thus, an element represented in a plural form may also include a single element, or an element represented in a singular form may include multiple elements.

[0411] The embodiments described and illustrated in the specification and drawings are merely specific embodiments presented to facilitate the explanation of the technical content of this disclosure and to aid in understanding it, and are not intended to limit the scope of this disclosure. That is, it will be apparent to those skilled in the art that other variations based on the technical concepts of this disclosure can be implemented. Furthermore, the corresponding embodiments described above can be combined if desired. For example, a portion of an embodiment of this disclosure can be combined with a portion of another embodiment to operate a base station and a terminal. As an example, a portion of a first embodiment of this disclosure can be combined with a portion of a second embodiment to operate a base station and a terminal. Moreover, although the above embodiments have been described based on an FDD LTE system, other variations based on the technical concepts of the embodiments can be implemented in other communication systems such as TDD LTE and 5G or NR systems.

[0412] In the accompanying drawings describing the methods of this disclosure, the order of description does not always correspond to the order of execution steps, and the order of steps can be changed or steps can be executed in parallel.

[0413] Alternatively, in the accompanying drawings describing the methods of this disclosure, some elements may be omitted without departing from the essential spirit and scope of this disclosure, and only some elements may be included.

[0414] Furthermore, in the methods of this disclosure, some or all of the contents of each embodiment may be combined and implemented without departing from the essential spirit and scope of this disclosure.

[0415] Various embodiments of this disclosure have been described above. The above description is for illustrative purposes and is not intended to limit the embodiments of this disclosure to those set forth herein. Those skilled in the art will understand that other specific modifications and changes can be readily made to the form of this disclosure without altering its technical concept or essential characteristics. The scope of this disclosure is defined by the appended claims rather than the detailed description above, and the scope of this disclosure should be interpreted to include all variations or modifications derived from the meaning and scope of the claims and their equivalents.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receive downlink control information from the base station, including the bandwidth portion BWP indicator field and the first field; as well as DCI size alignment is performed on the first field and the corresponding second field included in the DCI, where the second field is the field required for DCI format interpretation of the BWP as indicated by the BWP indicator field. The DCI is associated with multi-cell scheduling, and when the first field includes multiple first blocks corresponding to each cell configured for the multi-cell scheduling, the DCI size alignment is applied on a per-block basis.

2. The method according to claim 1, wherein, The DCI size alignment applied on a per-block basis is applied separately to each of the plurality of first blocks.

3. The method of claim 2, further comprising receiving information from the base station indicating a scheme for the DCI size alignment, in, The information indicates either a scheme based on blocks or a scheme based on fields.

4. The method according to claim 3, wherein, Performing the DCI size alignment further includes: If the size of a first block in the plurality of first blocks is less than the size of a second block in the second field corresponding to the first block, at least one bit with a value of 0 is added to the first block until the size of the first block is equal to the size of the second block; and If the size of the first block in the plurality of first blocks is greater than the size of the second block in the second field corresponding to the first block, the least significant bit of the first block corresponding to the size of the second block is used.

5. The method according to claim 3, wherein, The DCI is associated with multi-cell scheduling, and in the absence of multiple first blocks corresponding to the various cells configured for the multi-cell scheduling in the first field, the DCI size alignment is applied on a per-field basis, and The DCI size alignment further includes: If the size of the first field is less than the size of the second field, add at least one bit with a value of 0 to the first field until the size of the first field equals the size of the second field; and If the size of the first field is greater than the size of the second field, the least significant bit of the first field corresponding to the size of the second field is used.

6. The method according to claim 1, wherein, The DCI size alignment is further applied on a per-field basis.

7. The method according to claim 6, wherein, Performing the DCI size alignment further includes: Determine the field with the larger field size between the first field and the second field; and Based on the determined results, the DCI size alignment is performed on a per-block or per-field basis. Where the size of the first field is greater than the size of the second field, the DCI size alignment is applied on a per-field basis, and Where the size of the first field is smaller than the size of the second field, the DCI size alignment is applied on a per-block basis.

8. The method according to claim 6, wherein, Performing the DCI size alignment further includes: determining the number of bits in the first field to be included in the second field when applying the DCI size alignment per block, and the number of bits in the first field to be included in the second field when applying the DCI size alignment per field. Where, when applying DCI size alignment per block, the number of bits to be included in the second field from the bits included in the first field is greater than the number of bits to be included in the second field from the bits included in the first field when applying DCI size alignment per field, then DCI size alignment is applied per block. Where, when applying DCI size alignment per block, the number of bits to be included in the second field from the bits included in the first field is less than the number of bits to be included in the second field from the bits included in the first field when applying DCI size alignment per field, the DCI size alignment is applied per field.

9. A terminal in a wireless communication system, the terminal comprising: transceiver; as well as Controller, the controller being connected to the transceiver, The controller is configured as follows: Receive downlink control information from the base station, including the bandwidth portion BWP indicator field and the first field; and DCI size alignment is performed on the first field and the corresponding second field included in the DCI, where the second field is the field required for DCI format interpretation of the BWP as indicated by the BWP indicator field. The DCI is associated with multi-cell scheduling, and when the first field includes multiple first blocks corresponding to each cell configured for the multi-cell scheduling, the DCI size alignment is applied on a per-block basis.

10. The terminal according to claim 9, wherein, The DCI size alignment applied on a per-block basis is applied separately to each of the plurality of first blocks.

11. The terminal of claim 10, wherein the controller is further configured to receive information from the base station indicating a scheme for the DCI size alignment, and in, The information indicates either a scheme based on each block or a scheme based on each field.

12. The terminal of claim 11, wherein, in order to perform the DCI size alignment, the controller is further configured to: If the size of a first block in the plurality of first blocks is less than the size of a second block in the second field corresponding to the first block, at least one bit with a value of 0 is added to the first block until the size of the first block is equal to the size of the second block; and If the size of the first block in the plurality of first blocks is greater than the size of the second block in the second field corresponding to the first block, the least significant bit of the first block corresponding to the size of the second block is used.

13. The terminal according to claim 11, wherein, The DCI is associated with multi-cell scheduling, and in the absence of multiple first blocks corresponding to the various cells configured for the multi-cell scheduling in the first field, the DCI size alignment is applied on a per-field basis, and In order to perform the DCI size alignment, the controller is further configured to: If the size of the first field is less than the size of the second field, add at least one bit with a value of 0 to the first field until the size of the first field equals the size of the second field; and If the size of the first field is greater than the size of the second field, the least significant bit of the first field corresponding to the size of the second field is used.

14. The terminal according to claim 9, wherein, The DCI size alignment is further applied on a per-field basis.

15. The terminal according to claim 14, wherein, In order to perform the DCI size alignment, the controller is further configured to: Identify the field with the larger field size between the first field and the second field; as well as Based on the determined results, the DCI size alignment is performed on a per-block or per-field basis. Where the size of the first field is greater than the size of the second field, the DCI size alignment is applied on a per-field basis, and Where the size of the first field is smaller than the size of the second field, the DCI size alignment is applied on a per-block basis.

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