Apparatus and method for multi-carrier scheduling in a wireless communication system - Patents.com

Abstract

The present disclosure is for performing multi-carrier scheduling in a wireless communication system, and an operation method of a user equipment (UE) may include the steps of performing a connection procedure with a base station, performing a connection establishment procedure for a primary cell with the base station, performing a connection establishment procedure for at least one secondary cell with the base station, receiving downlink control information (DCI) from the base station, and receiving data using resources indicated by the DCI.

Description

[Technical field]

[0001] The following description relates to wireless communication systems, and to an apparatus and method for multi-carrier scheduling in a wireless communication system. [Background technology]

[0002] Wireless access systems have been widely deployed to provide various types of communication services such as voice and data. In general, wireless access systems are multiple access systems that can support communication with multiple users by sharing available system resources (such as bandwidth and transmission power). Examples of multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, etc.

[0003] In particular, as many communication devices require large communication capacity, enhanced mobile broadband (eMBB) communication technology has been proposed, which is more advanced than the existing radio access technology (RAT). In addition, not only massive machine type communications (mMTC) that provides various services anytime and anywhere by connecting multiple devices and things, but also communication systems that consider reliability and latency sensitive services / user equipment (UE) have been proposed. Various technical configurations have been proposed for this purpose. Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure can provide apparatus and methods for more effectively allocating resources in a wireless communication system.

[0005] The present disclosure can provide an apparatus and method for multi-carrier scheduling in a wireless communication system.

[0006] The present disclosure may provide an apparatus and method for allocating resources for multiple cells using a physical downlink control channel (PDCCH) of one cell in a wireless communication system.

[0007] The present disclosure can provide an apparatus and method for scheduling physical downlink shared channels (PDSCHs) or physical uplink shared channels (PUSCHs) of multiple cells using a PDCCH of one cell in a wireless communication system.

[0008] The present disclosure may provide an apparatus and method for transmitting and receiving downlink control information (DCI) including scheduling information for multiple cells via a PDCCH of one cell in a wireless communication system.

[0009] The present disclosure can provide an apparatus and method for configuring modulation and coding scheme (MCS) fields for multiple cells in a wireless communication system.

[0010] The present disclosure may provide an apparatus and method for including MCS values ​​for multiple cells in an MCS field in a wireless communication system.

[0011] The present disclosure may provide an apparatus and method for indicating MCS information using a portion of an MCS index defined in an MCS table in a wireless communication system.

[0012] The present disclosure may provide an apparatus and method for defining an MCS table based on a number of cells that are scheduled together in a wireless communication system.

[0013] The present disclosure may provide an apparatus and method for splitting an MCS field for multiple cells in a wireless communication system.

[0014] The present disclosure may provide an apparatus and method for indicating MCS information for multiple cells using a common MCS value in a wireless communication system.

[0015] The present disclosure can provide an apparatus and method for indicating MCS information for multiple cells using a reference MCS value and a delta value in a wireless communication system.

[0016] The present disclosure may provide an apparatus and method for indicating MCS information of multiple transport blocks (TBs) using a common MCS value in a wireless communication system.

[0017] The technical problems to be solved by the present disclosure are not limited to those described above, and other technical problems not described above can be considered by a person of ordinary skill in the art to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below. [Means for solving the problem]

[0018] As an example of the present disclosure, a method of operating a user equipment (UE) in a wireless communication system may include the steps of performing a connection procedure with a base station, performing a connection establishment procedure for a primary cell with the base station, performing a connection establishment procedure for at least one secondary cell with the base station, receiving downlink control information (DCI) from the base station, and receiving data using resources indicated by the DCI. The DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0019] As an example of the present disclosure, a method of operating a base station in a wireless communication system may include the steps of performing a connection procedure with a UE (user equipment), performing a connection establishment procedure for a primary cell of the UE, performing a connection establishment procedure for at least one secondary cell of the UE, transmitting downlink control information (DCI) to the UE, and transmitting data using resources indicated by the DCI.

[0020] The DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0021] As an example of the present disclosure, a UE (user equipment) in a wireless communication system includes a transceiver and a processor connected to the transceiver, wherein the processor performs a connection procedure with a base station, performs a connection establishment procedure for a primary cell with the base station, performs a connection establishment procedure for at least one secondary cell with the base station, receives downlink control information (DCI) from the base station, and controls to receive data using resources indicated by the DCI, and the DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0022] As an example of the present disclosure, a base station in a wireless communication system includes a transceiver and a processor connected to the transceiver, wherein the processor performs a connection procedure with a UE (user equipment), performs a connection establishment procedure for a primary cell of the UE, performs a connection establishment procedure for at least one secondary cell of the UE, transmits downlink control information (DCI) to the UE, and controls the UE to transmit data using resources indicated by the DCI, and the DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0023] As an example of the present disclosure, a communication device includes at least one processor and at least one computer memory connected to the at least one processor and storing instructions for instructing operations by being executed by the at least one processor, the operations may include a step of performing a connection procedure with a base station, a step of performing a connection establishment procedure for a primary cell with the base station, a step of performing a connection establishment procedure for at least one secondary cell with the base station, a step of receiving downlink control information (DCI) from the base station, and a step of receiving data using resources indicated by the DCI. The DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0024] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one instruction includes the at least one instruction executable by a processor, the at least one instruction instructing an apparatus to perform a connection procedure with a base station, perform a connection establishment procedure for a primary cell with the base station, perform a connection establishment procedure for at least one secondary cell with the base station, receive downlink control information (DCI) from the base station, and receive data using resources indicated by the DCI, and the DCI may include information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

[0025] The above-described aspects of the present disclosure are merely some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure set forth below. Effect of the Invention

[0026] The embodiments according to the present disclosure may have the following advantages.

[0027] According to the present disclosure, scheduling for multiple cells can be performed efficiently.

[0028] The effects obtained by the embodiments of the present disclosure are not limited to the effects described above, and other effects not described above can be clearly derived and understood by a person having ordinary skill in the art to which the technical configuration of the present disclosure is applied from the following description of the embodiments of the present disclosure. In other words, unintended effects by implementing the configuration described in the present disclosure can also be derived from the embodiments of the present disclosure by a person having ordinary skill in the art. [Brief description of the drawings]

[0029] The drawings attached below are for aiding understanding of the present disclosure, and together with the detailed description, can provide examples of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing can be combined with each other to form a new embodiment. The reference numerals in each drawing can refer to structural elements.

[0030] [Figure 1] FIG. 1 illustrates a structure of a wireless communication system to which the present disclosure can be applied. [Diagram 2] FIG. 1 illustrates an example of a wireless device to which the present disclosure can be applied. [Diagram 3] 1 is a diagram illustrating a frame structure in a wireless communication system to which the present disclosure can be applied. [Figure 4]FIG. 1 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied. [Diagram 5] FIG. 1 is a diagram illustrating a physical resource block in a wireless communication system to which the present disclosure can be applied. [Figure 6] FIG. 1 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied. [Figure 7] 1 is a diagram illustrating physical channels used in a wireless communication system to which the present disclosure can be applied, and a general signal transmission / reception method using these channels. [Figure 8] FIG. 1 is a diagram illustrating an example of an MCS table based on channel quality in a wireless communication system according to an embodiment of the present disclosure. [Figure 9] FIG. 1 is a diagram illustrating an example of MCS grouping for multi-carrier scheduling in a wireless communication system according to one embodiment of the present disclosure. [Figure 10] A figure showing an example of MCS index groups in multi-carrier scheduling in a wireless communication system according to one embodiment of the present disclosure. [Figure 11] FIG. 1 is a diagram showing an example of a cell group using the same MCS index in a wireless communication system according to one embodiment of the present disclosure. [Figure 12] A diagram showing an example of MCS-based delta operation of a reference CC in a wireless communication system according to one embodiment of the present disclosure. [Figure 13] FIG. 11 is a diagram showing an example of delta operation based on a reference MCS in a wireless communication system according to one embodiment of the present disclosure. [Figure 14] A figure showing an example of the structure of an MCS field of MC-DCI in a wireless communication system relating to one embodiment of the present disclosure. [Figure 15] A figure showing an example of the structure of an MCS field of MC-DCI in a wireless communication system relating to one embodiment of the present disclosure. [Figure 16]A diagram showing an example of a procedure in which a base station performs communication according to multi-carrier scheduling in a wireless communication system according to one embodiment of the present disclosure. [Figure 17] A diagram showing an example of a procedure in which a terminal performs communication according to multi-carrier scheduling in a wireless communication system according to one embodiment of the present disclosure. [Figure 18] A figure showing an example of a procedure for indicating a resource allocation status using an RNTI (radio network temporary identifier) ​​in a wireless communication system according to one embodiment of the present disclosure. [Figure 19] A diagram showing an example of a procedure for performing multi-carrier scheduling according to a separate-equal scheme in a wireless communication system according to one embodiment of the present disclosure. [Figure 20] A diagram showing an example of a procedure for performing multi-carrier scheduling according to a shared-common method in a wireless communication system according to one embodiment of the present disclosure. [Figure 21] A figure showing an example of a procedure for performing multi-carrier scheduling according to a shared-common method between cells and an individual delta method between TBs in a wireless communication system according to one embodiment of the present disclosure. [Figure 22] 1 is a diagram showing an example of a procedure for performing multi-carrier scheduling according to a separate-delta scheme in a wireless communication system according to one embodiment of the present disclosure. [Figure 23] A figure showing an example of a procedure for performing multi-carrier scheduling according to an individual-uniform scheme between cells and an individual-delta scheme between TBs in a wireless communication system according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] The following examples combine the components and features of the present disclosure in a specific form. Each component or feature can be considered optional unless otherwise explicitly stated. Each component or feature can be implemented in a form not combined with other components or features. Also, some components and / or features can be combined to configure the embodiments of the present disclosure. The order of operations described in the embodiments of the present disclosure can be changed. Some components or features of any of the embodiments can be included in other embodiments, or can be replaced with corresponding components or features of other embodiments.

[0032] In the description of the drawings, procedures or steps that may make the gist of the present disclosure unclear are not described, and procedures or steps that can be understood by a person skilled in the art are not described.

[0033] Throughout the specification, when a part "comprising" or "including" a certain element, this means that it can further include other elements, not excluding other elements, unless otherwise specified to the contrary. In addition, the terms "part," "unit," "module," and the like described in the specification mean a unit that processes at least one function or operation, which can be realized by hardware, software, or a combination of hardware and software. In addition, the words "a" or "an," "one," "the," and similar related words can be used in the context of describing this disclosure (particularly in the context of the claims below) to include both the singular and the plural, unless otherwise indicated in the specification or clearly contradicted by the context.

[0034] In the present specification, the embodiments of the present disclosure have been described with a focus on the data transmission / reception relationship between a base station and a mobile station. Here, the base station is meant as a terminal node of a network that directly communicates with a mobile station. Certain operations described as being performed by a base station in the present specification may also be performed by an upper node of the base station in some cases.

[0035] That is, in a network consisting of a plurality of network nodes including a base station, various operations performed for communication with a mobile station may be performed by the base station or other network nodes other than the base station. In this case, the term "base station" may be replaced with a term such as a fixed station, Node B, eNB (eNode B), gNB (gNode B), ng-eNB, advanced base station (ABS), or access point.

[0036] In addition, in the embodiments of the present disclosure, the term "terminal" may be replaced with terms such as user equipment (UE), mobile station (MS), subscriber station (SS), mobile subscriber station (MSS), mobile terminal, or advanced mobile station (AMS).

[0037] Also, the transmitting end refers to a fixed and / or mobile node that provides a data service or a voice service, and the receiving end refers to a fixed and / or mobile node that receives a data service or a voice service. Thus, in the case of an uplink, a mobile station can be the transmitting end and a base station can be the receiving end. Similarly, in the case of a downlink, a mobile station can be the receiving end and a base station can be the transmitting end.

[0038] An embodiment of the present disclosure may be supported by standard documents disclosed in at least one of wireless access systems, such as an IEEE 802.xx system, a 3GPP (registered trademark) (3rd Generation Partnership Project) system, a 3GPP LTE (Long Term Evolution) system, a 3GPP 5G (5th generation) NR (New Radio) system, and a 3GPP2 system, and in particular, an embodiment of the present disclosure may be supported by 3GPP TS (technical specification) 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.321, and 3GPP TS 38.331 documents.

[0039] In addition, the embodiments of the present disclosure can be applied to other wireless access systems and are not limited to the above-mentioned systems. For example, the embodiments of the present disclosure can be applied to systems that are applied after the 3GPP 5G NR system and are not limited to a specific system.

[0040] That is, any steps or parts of the embodiments of the present disclosure that are not described may be explained by referring to the above documents, and all terms disclosed herein may be explained by the above standard documents.

[0041] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present disclosure, and is not intended to show the only embodiments in which the technical configuration of the present disclosure can be implemented.

[0042] Furthermore, specific terms used in the embodiments of the present disclosure are provided to aid in understanding the present disclosure, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present disclosure.

[0043] The following techniques can be applied to various wireless access systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single carrier frequency division multiple access (SC-FDMA).

[0044] For clarity of the following description, the description will be based on a 3GPP communication system (e.g., LTE, NR, etc.), but the technical idea of ​​the present disclosure is not limited thereto. LTE may refer to technology after 3GPP TS 36.xxx Release 8. In particular, LTE technology after 3GPP TS 36.xxx Release 10 may be referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 may be referred to as LTE-A pro. 3GPP NR may refer to technology after TS 38.xxx Release 15. 3GPP 6G may refer to technology after TS Release 17 and / or Release 18. "xxx" refers to the detailed number of the standard document. LTE / NR / 6G may be referred to as a 3GPP system.

[0045] 3GPP 6G may refer to technology after 3GPP NR based on the 3GPP system. 3GPP 6G is not limited to a release or a specific TS document, and the name may be in a form different from 3GPP 6G. That is, 3GPP 6G may refer to technology introduced after 3GPP NR, and is not limited to a specific form.

[0046] The following description will be centered on the 3GPP NR system, but is not limited thereto and can also be applied to 3GPP 6G. Furthermore, the following description may be partially modified in consideration of the 3GPP 6G system and is not limited to a specific form. However, the following description will be centered on the 3GPP NR system for convenience of explanation. For background techniques, terms, abbreviations, etc. used in this disclosure, reference may be made to the matters described in standard documents published prior to this disclosure. For example, reference may be made to the 36.xxx and 38.xxx standard documents.

[0047] System in general

[0048] As more communication devices require larger communication capacity, the need for improved mobile broadband communication compared to existing radio access technology (RAT) is emerging. Massive MTC (Machine Type Communications), which connects a large number of devices and objects to provide various services anytime and anywhere, is also one of the major issues considered in next-generation communication. In addition, communication system design considering reliability and latency-sensitive services / terminals is being discussed. Thus, the introduction of next-generation RATs considering eMBB (enhanced mobile broadband communication), mMTC (massive MTC), URLLC (Ultra-Reliable and Low Latency Communication), etc. is being discussed, and in this disclosure, for convenience, the technology is referred to as NR. NR is an expression indicating an example of 5G RAT.

[0049] New RAT systems including NR use an OFDM transmission scheme or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but support a larger system bandwidth (e.g., 100 MHz). Alternatively, one cell may support multiple numerologies. That is, terminals operating with different numerologies may coexist in one cell.

[0050] A numerology corresponds to one subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0051] Also, new RAT systems including 6G can be considered as next-generation RATs. New RAT systems including 6G can consider, but are not limited to, i) very high data rates per device, ii) a very large number of connected devices, iii) global connectivity, iv) very low latency, v) low energy consumption for battery-free IoT devices, vi) ultra-reliable connections, and vii) connected intelligence with machine learning capabilities. New RAT systems including 6G can consider the above-mentioned aspects and can consider the use of THz (Terahertz) frequency bands at higher frequencies than NR systems for wider bandwidth and higher transmission speeds. New RAT systems including 6G can apply AI / ML (artificial intelligence / machine learning) to overcome existing limitations, but are not limited to this.

[0052] FIG. 1 is a diagram illustrating a structure of a wireless communication system to which the present disclosure can be applied. Referring to FIG. 1, the NG-RAN is composed of a gNB that provides a NG-RA (NG-Radio Access) user plane (i.e., a new AS (access stratum) sub-layer / PDCP (Packet Data Convergence Protocol) / RLC (Radio Link Control) / MAC / PHY) and a control plane (RRC) protocol termination for a UE. The gNBs are interconnected via an Xn interface. The gNBs are also connected to an NGC (New Generation Core) via an NG interface. More specifically, the gNBs are connected to an AMF (Access and Mobility Management Function) via an N2 interface and to a UPF (User Plane Function) via an N3 interface. FIG. 1 is a structure based on an NR system, and in a 6G system, the structure of FIG. 1 may be used in the same manner or with some changes, and is not limited to a specific form.

[0053] FIG. 2 is a diagram illustrating an example of a wireless device to which the present disclosure can be applied.

[0054] 2, a wireless device 200 may transmit and receive wireless signals via various wireless access technologies (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G). The wireless device 200 may include at least one processor 202 and at least one memory 204, and may further include at least one transceiver 206 and / or at least one antenna 208.

[0055] The processor 202 may be configured to control the memory 204 and / or the transceiver 206 to implement the description, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. For example, the processor 202 may process information in the memory 204 to generate a first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver 206. The processor 202 may also receive a wireless signal including a second information / signal via the transceiver 206, and then store information obtained from signal processing of the second information / signal in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions for performing some or all of the processes controlled by the processor 202 or performing the description, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. Here, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement wireless communication technology. The transceiver 206 may be connected to the processor 202 and may transmit and / or receive wireless signals via at least one antenna 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be mixed with a radio frequency (RF) unit. In this disclosure, a wireless device may also refer to a communication modem / circuit / chip.

[0056] The hardware elements of the wireless device 200 are described in more detail below. At least one protocol layer may be implemented by the at least one processor 202, without being limited thereto. For example, the at least one processor 202 may implement at least one layer (e.g., functional layers such as physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC), service data adaptation protocol (SDAP), etc.). The at least one processor 202 may generate at least one protocol data unit (PDU) and / or at least one service data unit (SDU) according to the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. The at least one processor 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. The at least one processor 202 can generate and provide signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information to the at least one transceiver 206 according to the functions, procedures, suggestions, and / or methods disclosed herein. The at least one processor 202 can receive signals (e.g., baseband signals) from the at least one transceiver 206 and obtain the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein.

[0057] The at least one processor 202 may also be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The at least one processor 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, the at least one processor 202 may include at least one application specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate arrays (FPGA). The descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein may be included in the at least one processor 202 or may be stored in the at least one memory 204 and executed by the at least one processor 202. The descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed herein may be implemented using firmware or software in the form of code, instructions and / or collections of instructions.

[0058] At least one memory 204 may be connected to the at least one processor 202 and may store various types of data, signals, messages, information, programs, codes, instructions, and / or commands. The at least one memory 204 may be comprised of a read only memory (ROM), a random access memory (RAM), an erasable programmable read only memory (EPROM), a flash memory, a hard drive, a register, a cache memory, a computer readable storage medium, and / or a combination thereof. The at least one memory 204 may be located internal and / or external to the at least one processor 202. Also, the at least one memory 204 may be connected to the at least one processor 202 via various technologies, such as a wired or wireless connection.

[0059] The at least one transceiver 206 can transmit user data, control information, wireless signals / channels, etc., as described in the methods and / or operational flowcharts herein, etc., to at least one other device. The at least one transceiver 206 can receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts herein, etc., from at least one other device. For example, the at least one transceiver 206 can be coupled to at least one processor 202 and can transmit and receive wireless signals. For example, the at least one processor 202 can control the at least one transceiver 206 to transmit user data, control information, or wireless signals to at least one other device. Also, the at least one processor 202 can control the at least one transceiver 206 to receive user data, control information, or wireless signals from at least one other device. Also, the at least one transceiver 206 may be connected to at least one antenna 208, and the at least one transceiver 206 may be configured to transmit and receive user data, control information, radio signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein, via the at least one antenna 208. In this specification, the at least one antenna may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). The at least one transceiver 206 may convert the received radio signals / channels, etc., from an RF band signal to a baseband signal, for processing the received user data, control information, radio signals / channels, etc., using the at least one processor 202. The at least one transceiver 206 may convert the user data, control information, radio signals / channels, etc., processed using the at least one processor 202, from a baseband signal to an RF band signal. For this purpose, the at least one transceiver 206 may include an (analog) oscillator and / or a filter.

[0060] The components of the wireless device described with reference to Fig. 2 may be referred to by other terms from the viewpoint of functionality. For example, the processor 202 may be referred to as a control unit, the transceiver 206 as a communication unit, and the memory 204 as a storage unit. Depending on the case, the communication unit may be used to include at least a part of the processor 202 and the transceiver 206.

[0061] The structure of the wireless device described with reference to FIG. 2 can be understood as the structure of at least a part of various devices. As an example, it is at least a part of various devices (e.g., a robot, a vehicle, an XR device, a mobile device, a home appliance device, an IoT device, an AI device / server, etc.). Furthermore, in various embodiments, in addition to the components illustrated in FIG. 2, the device may further include other components.

[0062] For example, the device may be a mobile device such as a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), a portable computer (e.g., a laptop, etc.), etc. In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an interface unit that includes at least one port (e.g., an audio input / output port, a video input / output port) for connection to another device, and an input / output unit for inputting and outputting image information / signals, audio information / signals, data, and / or information input by a user.

[0063] For example, the device may be a mobile device such as a mobile robot, a vehicle, a train, an aerial vehicle (AV), a ship, etc. In this case, the device may further include at least one of a driving unit including at least one of an engine, a motor, a power train, a wheel, a brake, and a steering device of the device, a power supply unit including a wired / wireless charging circuit, a battery, etc. that supplies power, a sensor unit that detects status information, environmental information, and user information of the device or its surroundings, an autonomous driving unit that performs functions such as route maintenance, speed adjustment, and destination setting, and a position measurement unit that obtains position information of the mobile device through a global positioning system (GPS) and various sensors.

[0064] For example, the device may be an XR device such as an HMD, a head-up display (HUD) installed in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, a digital signage, a vehicle, a robot, etc. In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an input / output unit that obtains control information, data, etc. from the outside and outputs the generated XR object, and a sensor unit that detects status information, environmental information, and user information of the device or its surroundings.

[0065] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc., depending on the purpose or field of use. In this case, the device may further include at least one of a sensor unit that detects status information, environmental information, and user information of the device or its surroundings, and a driving unit that performs various physical operations such as moving a robot joint.

[0066] For example, the device may be an AI device such as a television, a projector, a smartphone, a PC, a notebook computer, a digital broadcasting terminal, a tablet PC, a wearable device, a set-top box (STB), a radio, a washing machine, a refrigerator, a digital signage, a robot, or a vehicle. In this case, the device may further include at least one of an input unit for acquiring various types of data from the outside, an output unit for generating an output related to vision, hearing, or touch, a sensor unit for detecting state information, environmental information, and user information of the device or its surroundings, and a training unit for learning a model configured of an artificial neural network using learning data. The structure of the wireless device illustrated in FIG. 2 may be understood as a part of a RAN node (e.g., a base station, a DU, a RU, an RRH, etc.). That is, the device illustrated in FIG. 2 may be a RAN node. In this case, the device may further include a wired transceiver for front haul and / or back haul communication. However, if the fronthaul and / or backhaul communication is based on wireless communication, at least one transceiver 206 illustrated in FIG. 2 may be used for the fronthaul and / or backhaul communication, and no wired transceiver may be included.

[0067] FIG. 3 is a diagram illustrating a frame structure in a wireless communication system to which the present disclosure can be applied.

[0068] The NR system can support multiple numerologies, where a numerology can be defined by a subcarrier spacing and a cyclic prefix (CP) overhead. In this case, multiple subcarrier spacings can be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). In addition, the numerology used can be selected independently of the frequency band, even if it is assumed that very low subcarrier spacings are not used at very high carrier frequencies. In addition, the NR system can support various frame structures with multiple numerologies.

[0069] The following describes OFDM numerologies and frame structures that can be considered in the NR system. A number of OFDM numerologies supported in the NR system can be defined as shown in Table 1 below.

[0070] [Table 1]

[0071] NR supports multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, a 15kHz SCS supports wide areas in traditional cellular bands, a 30kHz / 60kHz SCS supports dense urban areas, lower latency, and wider carrier bandwidth, and a 60kHz or higher SCS supports bandwidths wider than 24.25GHz to overcome phase noise.

[0072] The NR frequency band is defined as two types of frequency ranges (FR1 and FR2). FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 can mean millimeter wave (mmW).

[0073] [Table 2]

[0074] JPEG2025514959000004.jpg124157

[0075] JPEG2025514959000005.jpg27157

[0076] [Table 3]

[0077] [Table 4]

[0078] FIG. 3 is an example when μ=2 (SCS is 60 kHz). Referring to Table 3, one subframe can include four slots. One subframe={1, 2, 4} slots shown in FIG. 3 is an example, and the number of slots that can be included in one subframe is defined as in Table 3 or Table 4. Also, a mini-slot may include 2, 4, or 7 symbols, or may include more or less symbols than that.

[0079] In relation to physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. are considered. The physical resources that can be considered in an NR system are specifically described below.

[0080] First, with respect to antenna ports, an antenna port is defined such that the channel on which a symbol on an antenna port is carried can be inferred from the channel on which another symbol on the same antenna port is carried. If the large-scale properties of the channel on which a symbol on one antenna port is carried can be inferred from the channel on which a symbol on the other antenna port is carried, the two antenna ports are said to be in a quasi co-located (QC / QCL) relationship. Here, the large-scale properties include one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

[0081] In the 6G system, communication can be performed at the above-mentioned terahertz frequency, which is a higher frequency than millimeter wave (mmW), and a frame structure of the same form as that shown in FIG. 3 can be used, or a separate frame structure for the 6G system can be used, and is not limited to a specific form.

[0082] FIG. 4 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0083] JPEG2025514959000008.jpg135157

[0084] Point A serves as a common reference point for the resource block grid and is obtained as follows:

[0085] - offsetToPointA for the primary cell (PCell) downlink indicates the frequency offset between the lowest subcarrier of the lowest resource block overlapping with the SS / PBCH block used by the terminal for initial cell selection and point A. It is expressed in resource block units assuming a subcarrier spacing of 15 kHz for FR1 and a subcarrier spacing of 60 kHz for FR2.

[0086] -absoluteFrequencyPointA indicates the frequency-location of point A expressed as ARFCN (absolute radio-frequency channel number).

[0087] Common resource blocks are numbered from 0 upwards in the frequency domain for a subcarrier spacing setting μ. The center of subcarrier 0 of common resource block 0 for a subcarrier spacing setting μ coincides with "point A". Common resource block number in the frequency domain The relationship between JPEG2025514959000009.jpg811 and the resource element (k, l) for the subcarrier spacing setting μ is given by the following Equation 1.

[0088] [Formula 1]

number

[0089] JPEG2025514959000011.jpg35157

[0090] [Formula 2]

number

[0091] JPEG2025514959000013.jpg619 is the common resource block where the BWP starts relative to common resource block 0.

[0092] Fig. 5 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied, and Fig. 6 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0093] 5 and 6, a slot includes multiple symbols in the time domain. For example, in the case of normal CP, one slot includes seven symbols, while in the case of extended CP, one slot includes six symbols.

[0094] A carrier includes multiple subcarriers in the frequency domain. A resource block (RB) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A bandwidth part (BWP) is defined as multiple consecutive (physical) resource blocks in the frequency domain and can correspond to one numerology (e.g., SCS, CP length, etc.). A carrier can include up to N (e.g., 5) BWPs. Data communication is performed via the activated BWPs, and only one BWP can be activated for one terminal. In the resource grid, each element is called a resource element (RE), and one complex symbol can be mapped to it.

[0095] The NR system can support up to 400 MHz per component carrier (CC). If a terminal operating in such a wideband CC always operates with the radio frequency (RF) chip for the entire CC turned on, the terminal battery may consume a lot of power. Alternatively, when considering various use cases (e.g., eMBB, URLLC, Mmtc, V2X, etc.) operating in one wideband CC, different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band in the CC. Alternatively, the capability for maximum bandwidth may differ for each terminal. In consideration of this, the base station may instruct the terminal to operate only in a part of the bandwidth rather than the entire bandwidth of the wideband CC, and the part of the bandwidth is defined as a bandwidth part (BWP) for convenience. The BWP may be composed of continuous RBs on the frequency axis and may correspond to one numerology (e.g., subcarrier spacing, CP length, slot / minislot interval).

[0096] Meanwhile, the base station can set multiple BWPs even within one CC set in the terminal. For example, in the PDCCH monitoring slot, a BWP occupying a relatively small frequency region can be set, and the PDSCH indicated in the PDCCH can be scheduled on a larger BWP. Alternatively, when UEs gather in a specific BWP, some terminals can be set to other BWPs for load balancing. Alternatively, in consideration of frequency domain inter-cell interference cancellation between adjacent cells, a central part of the spectrum of the entire bandwidth can be excluded, and both side BWPs can be set in the same slot. That is, the base station can set at least one DL / UL BWP to a terminal associated with a wideband CC. The base station can activate at least one DL / UL BWP among the DL / UL BWPs set at a specific time (by L1 signaling, MAC CE (control element), RRC signaling, etc.). Also, the base station may instruct switching to another configured DL / UL BWP (by L1 signaling, MAC CE, RRC signaling, etc.). Or, when a timer value expires on a timer basis, switching to the configured DL / UL BWP may be performed. In this case, the activated DL / UL BWP is defined as an active DL / UL BWP. However, in a situation where the UE is performing an initial access process or before an RRC connection is set up, it may not be possible to receive a configuration for the DL / UL BWP, so the DL / UL BWP assumed by the UE in such a situation is defined as the initially active DL / UL BWP.

[0097] FIG. 7 illustrates examples of physical channels used in a wireless communication system to which the present disclosure can be applied, and a general signal transmission / reception method using these channels.

[0098] In a wireless communication system, a terminal receives information from a base station through a downlink, and transmits information to the base station through an uplink. Information transmitted and received between the base station and the terminal includes data and various control information, and various physical channels exist according to the type / application of the information transmitted and received.

[0099] When the terminal is powered on or newly enters a cell, the terminal performs an initial cell search such as synchronizing with a base station (S701). To this end, the terminal can receive a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell identifier (ID). Then, the terminal can receive a physical broadcast channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a downlink reference signal (DL RS) in the initial cell search stage to check the downlink channel state.

[0100] After completing the initial cell search, the terminal can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on the information carried on the PDCCH (S702).

[0101] On the other hand, when the terminal first connects to the base station or does not have radio resources for signal transmission, the terminal can perform a random access procedure (RACH) to the base station (steps S703 to S706). To this end, the terminal can transmit a specific sequence to a preamble via a physical random access channel (PRACH) (S703 and S705) and receive a response message to the preamble via a PDCCH and a corresponding PDSCH (S704 and S706). In the case of a contention-based RACH, a contention resolution procedure can also be performed.

[0102] After performing the above-mentioned procedure, the terminal can then perform PDCCH / PDSCH reception (S707) and Physical Uplink Shared Channel (PUSCH) / Physical Uplink Control Channel (PUCCH) transmission (S708) as a general uplink / downlink signal transmission procedure. In particular, the terminal receives Downlink Control Information (DCI) via the PDCCH. Here, the DCI includes control information such as resource allocation information for the terminal, and has different formats depending on its purpose.

[0103] Meanwhile, control information that a terminal transmits to a base station via an uplink or that the terminal receives from a base station includes downlink / uplink ACK / NACK (Acknowledgement / Non-Acknowledgement) signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator), etc. In the case of a 3GPP LTE system, a terminal can transmit the above-mentioned control information such as CQI / PMI / RI via a PUSCH and / or a PUCCH.

[0104] Specific Examples of the Disclosure

[0105] Hereinafter, the present disclosure describes a technique for simultaneously controlling multiple cells using one physical downlink control channel (PDCCH) in a base station supporting carrier aggregation. Specifically, the present disclosure describes various embodiments in which a base station controls scheduling for transmission of physical downlink shared channels (PDSCHs) of multiple cells via one PDCCH. The multiple cells may include at least one of a primary cell (Pcell), a secondary cell (Scell), a secondary-secondary cell (sScell), or a primary-secondary cell (pScell).

[0106] 5G NR (new radio) is a technology that provides services mainly through the main technologies of eMBB (enhanced mobile broadband), URLLC (ultra-reliable low-latency communications), and mIoT (massive IoT). eMBB is a technology that focuses mainly on improving speed and transmits more information by expanding the spectrum from LTE (long term evolution). eMBB is an important frequency merging technology that is widely used in 5G NR.

[0107] Currently, 5G NR is based on the principle that the PDCCH of each cell schedules the PDSCH responsible for data transmission to the cell. That is, the base station must generally perform one scheduling via the PDCCH to trigger one PDSCH transmission. In addition, in a carrier aggregation situation, that is, in a situation in which PDSCH is transmitted via multiple cells to improve data throughput from the perspective of eMBB, the base station must inform the terminal of scheduling information via the PDCCH for each cell in order to simultaneously transmit PDSCH via multiple cells. This is a basic operation that has been performed since 4G LTE.

[0108] However, as the number of frequency bands that can be supported by 5G NR increases, the number of cells used for carrier aggregation in 5G NR may be greater than the number of cells used for carrier aggregation in LTE. Therefore, if the conventional method of performing scheduling via PDCCH for each cell is applied to 5G NR, the terminal consumes a lot of resources to decode the scheduling information.

[0109] Therefore, the present disclosure proposes a method for scheduling PDSCHs of multiple cells using one PDCCH in one cell. In particular, the present disclosure proposes a technique for indicating MCS (modulation and coding scheme) information for PDSCHs of multiple cells in one PDCCH information for a specific cell in order to transmit PDSCH scheduling information of multiple cells to a terminal.

[0110] Currently, MCS information for one cell in a PDCCH is composed of 5 bits or 10 bits. Therefore, when a base station uses one PDCCH to simultaneously schedule PDSCHs of multiple cells, it is required to configure MCS information for multiple cells with bits corresponding to a multiple of existing bits (e.g., 5 bits or 10 bits). However, in this case, a problem may occur in that the number of bits occupied by MCS information in one PDCCH increases excessively. In particular, in 5G NR, in which the minimum transmission payload of a PDCCH is 140 bits or more, it is theoretically impossible to simultaneously transmit MCS information for multiple cells. Moreover, compared with multiple input multiple output (MIMO), frequency domain resource allocation (FDRA), or time domain resource allocation (TDRA) information, MCS information may not have common characteristics that can be shared between cells. Therefore, it can be said that MCS information for each of multiple cells is basically indicated individually as a rule. Nevertheless, when MCS information for multiple cells is allocated to a small number of bits, such as less than 5 or 10 bits, it is expected that the performance degradation problem that may occur due to PDCCH decoding in mobile broadband (MBB) can be partially solved.

[0111] The present disclosure proposes a scheme for minimizing the number of bits of MCS information that does not have common features that can be shared between cells or carriers among various PDSCH transmission-related fields included in one PDCCH in order to perform simultaneous scheduling for PDSCH transmissions of multiple cells using one PDCCH for one cell in a carrier aggregation situation. That is, the present disclosure proposes a scheme for minimizing the number of bits of MCS information for multiple cells and allocating MCS information to multiple cells or multiple carriers via one PDCCH.

[0112] Generally, MCS for each cell or carrier can be expressed by one of 32 indexes. An index indicating MCS for each cell or carrier, i.e., MCS index, can be expressed by 5 bits. When data is spatially divided and transmitted by applying MIMO multiplexing in a base station, two transport blocks (TBs) are simultaneously transmitted from the L2 MAC layer to the L1 layer. In this case, MCS indexes for each of the two TBs must be notified to a terminal. Therefore, the number of bits of the MCS field can be a minimum of 5 bits to a maximum of 10 bits for each cell or carrier. In the worst case, if 10 bits are used for each cell, when scheduling is performed for up to four scheduled component carriers (CCs) in one PDCCH, the MCS information in one PDCCH can be a maximum of 40 bits (10 bits x 4 (= number of CCs)). This corresponds to about 30% of the maximum payload bit number of 140 bits available for one PDCCH. Generally, one PDCCH may include various fields such as MIMO, FDRA, or TDRA in addition to the MCS index. Therefore, it is not desirable to use a large number of bits for MCS information allocation for multiple cells in one PDCCH. The present disclosure proposes several methods that enable PDSCH scheduling for multiple cells (e.g., four CCs) using a number of bits much smaller than the number of bits mentioned above. In the present disclosure, a CC may be understood as an active bandwidth part (active BWP), a cell, etc., configured and / or indicated for the CC.

[0113] In various proposed methods, how the DCI (downlink control information) field information of the PDCCH is applied to the scheduled CC can be classified as shown in Table 5. Table 5 illustrates the characteristics of fields in one PDCCH for multi-CC scheduling.

[0114] [Table 5]

[0115] Table 5 shows the applicable feature classifications for various fields. For MCS information, various options can be proposed depending on which method is applied.

[0116] 1) Option 1: separate-equal

[0117] -Change the number of MCS indices that indicate MCS according to the number of CCs to be scheduled

[0118] -Method for changing the size of the MCS table

[0119] 2) Option 2: shared-common

[0120] - A method of pre-configuring carrier or cell information that shares the same MCS information

[0121] 3) Option-3: A method in which separate-equal is applied between cells and shared-common is applied between TBs.

[0122] 4) Option 4: separate-delta

[0123] -Indicate the difference from the MCS index specified in the standard CC

[0124] -Indicating a common MCS index within a group (or subset) of cells

[0125] 5) Option-5: A method in which separate-equal is applied between cells and separate-delta is applied between TBs

[0126] In the present disclosure, in order to reduce the DCI overhead for scheduling PDSCH and / or PUSCH (physical downlink shared channel) in a carrier aggregation situation where multiple cells are configured, a multi-cell scheduling scheme that jointly schedules multiple serving cells and / or CCs and the corresponding PDSCH / PUSCH transmissions with a single DCI based on the justification as shown in Table 6 below of Rel-18 may be considered.

[0127] [Table 6]

[0128] Hereinafter, the present disclosure will describe various embodiments for the configuration and interpretation of the FDRA field in a DCI for the structure design of a DCI performing multi-cell scheduling as described above, i.e., a multi-cell DCI (MC-DCI). The multi-cell scheduling operation for PDSCH transmission or PUSCH transmission described in the present disclosure can be applied in the same or similar manner to the case of multi-cell scheduling for PUSCH transmission or PDSCH transmission, respectively. In addition, in the present disclosure, a component carrier (CC) can be understood as an active bandwidth part (active BWP), a cell, etc. configured and / or indicated for the CC. Hereinafter, a CC scheduled in the present disclosure is also referred to as a co-scheduled CC. In addition, in the present disclosure, when cell grouping is performed for a plurality of cells included in a scheduled CC, one group can be referred to as a cell subgroup.

[0129] Hereinafter, the present disclosure proposes various options that enable PDSCH scheduling for multiple CCs by defining a structure and procedure so that the DCI field of the PDCCH for multi-carrier scheduling uses a minimum number of bits, not a multiple of the CC, in the current PDCCH DCI structure in which the MCS field occupies a minimum of 5 bits to a maximum of 10 bits depending on the number of TBs per CC. In this case, the following basic operations may be assumed. The basic operations according to various embodiments of the present disclosure are as follows.

[0130] A. A group of CCs sharing MCS information, i.e., a subset, can be predetermined in a higher layer (e.g., RRC layer or MAC layer). For example, a group of CCs can be predetermined for intra-band CCs, inter-band CCs, same sub-carrier spacing (SCS), or resource allocation (RA) type. Here, only one group can be formed, which means there is no subgrouping.

[0131] B. Basic information of the shared MCS can be provided semi-statically in the MAC layer or pre-configured in the RRC layer, and delta information or additional information for the MCS can be indicated via DCI.

[0132] C. The maximum number of CCs that can be scheduled together is not limited in principle. However, for convenience of explanation, the present disclosure assumes that the maximum number of CCs is 4. However, the present disclosure can be similarly applied to cases where the number of CCs is 4 or more. In addition, various embodiments can be applied to both downlink MCS and uplink MCS.

[0133] D. The base station can inform the terminal of which option to use depending on the situation via RRC signaling. That is, if the number of schedulable CCs is several tens, the base station can consider grouping CCs by each option.

[0134] E. When various MCS tables for ultra-reliable low-latency communications (URLLC) are applied to all CCs scheduled using multi-cell DCI (MC-DCI), the MC-DCI can be CRC (cyclic redundancy check) scrambled using MCS-cell-radio network temporary identifier (MCS-C-RNTI) and cell-radio network temporary identifier (C-RNTI). For a cell scheduled using MC-DCI, multiple MCS tables can be configured to operate with MCS-C-RNTI. If signaling is performed via MC-DCI scrambled with MCS-C-RNTI without multiple MCS tables being configured, the cell is treated as not actually scheduled. Furthermore, the MC-DCI can be restricted to be scrambled using only C-RNTI.

[0135] For multi-carrier scheduling, MCS-MC (multi cell)-RNTI corresponding to MCS-C-RNTI can be defined. That is, in the case of multi-cell carrier aggregation, the MCS of the entire aggregated carriers can be set to the general purpose MCS for URLCC, and MCS-MC-RNTI can be used to indicate this situation. Similarly, MC-RNTI corresponding to C-NRIT can be used. That is, RNTI for multi-carrier scheduling can be defined to indicate that multi-carrier is scheduled in MC-DCI. When defining RNTI for MC-DCI, DCI for scheduling one cell and DCI for scheduling multi-carrier can be distinguished.

[0136] F. At least one MCS table may be configured for each cell. In this case, a cell configured with two tables and a cell configured with one MCS table may be included in one CC group. When the MC-DCI for the CC group is scrambled using the MCS-C-RNTI, a cell that does not have an MCS table configured for URLCC among cells that belong to the CC group may be treated as not being scheduled. According to an embodiment, when multiple CCs are grouped, a rule may be defined that restricts cells configured with multiple MCS tables to be included in one CC group.

[0137] When a cell having G.URLLC features and a cell having no URLLC features are included in a CC group scheduled together, a rule can be defined to restrict MC-DCI to be scheduled only with C-RNTI and restrict MCS-C-RNTI to be used only for single cell scheduling. That is, a rule can be defined to restrict MCS-C-RNTI to be used when scheduling a single cell with MC-DCI and C-RNTI to be used when scheduling two or more cells with MC-DCI. Alternatively, a rule can be defined to restrict MCS-MC-RNTI to be used when scheduling a single cell with MC-DCI and MC-RNTI to be used when scheduling two or more cells with MC-DCI. Furthermore, a cell group can be grouped into cells that share DCI fields among scheduled CCs. For example, scheduled CCs can be grouped based on DCI fields that can be shared.

[0138] H. The base station can notify and / or configure in advance, via RRC signaling, the terminal as to which of the various options described below it will use.

[0139] I. In this disclosure, the CIF can be used to indicate the availability or number of cells of a cell group. In another embodiment, a new DCI field can be defined to indicate the availability or number of cells. The new DCI field can be defined with a size of 3 bits or more.

[0140] Option-1: separate-equal (changing the number of MCS indices to indicate the MCS according to the number of CCs to be scheduled)

[0141] The following Table 7 shows the existing 5G NR MCS table. The following Table 7 shows the modulation order Qm, TBS index, and redundancy version rv corresponding to the existing 32 MCS index information. idx Shows.

[0142] [Table 7]

[0143] Referring to Table 7, 32 MCS indexes are available, and one of the indexes defined in the table can be indicated by the DCI field. When one TB is transmitted, one MCS index can be transmitted in the DCI field of the PDCCH, and when two TBs are transmitted, two MCS indexes can be transmitted. Thus, as the number of CCs increases, the number of MCS indexes transmitted also increases. For example, two per CC for MCS information, and a maximum of CC x 2 x 5 bits can be required in the MC-DCI. Therefore, the present disclosure proposes a method of modifying the MCS table of Table 7, or operating a new MCS table of a small size defined by extracting a part from the MCS table of Table 7, or grouping indexes and using them together with a group ID, when controlling multiple cells using a DCI field of one PDCCH.

[0144] Hereinafter, various methods for jointly scheduling PDSCHs of multiple CCs with a small number of bits in MC-DCI in a PDCCH by reducing the number of MCS indexes compared to the existing MCS table will be described. Here, the number of bits of the MCS index can be changed according to the number of CCs.

[0145] 1-1. A new MCS table with a reduced number of indexes compared to the MCS table used in the existing single cell scheduling can be defined. The new MCS table can be a small-sized table in which the modulation order, TBS index, and redundancy version of the index are reconfigured based on the existing MCS table. The new MCS table can include only the lowest N indexes or the highest M indexes among the total N MCS indexes in the existing MCS table. Which table is used can be dynamically or statically notified via MC-DCI, media access control (MAC) control element (CE), or radio resource control (RRC) signaling depending on the SNR of the current cell or carrier.

[0146] FIG. 8 illustrates an example of an MCS table according to channel quality in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 8, when the channel quality (e.g., SNR (signal to noise ratio)) is greater than a first threshold, i.e., SNR high (810), the new MCS table can be configured with only the lowest M indexes among the total N MCS indexes in the existing MCS table. When the SNR is equal to or less than the first threshold and greater than a second threshold, i.e., SNR middle (820), the new MCS table can be configured with only the middle M indexes among the total N MCS indexes in the existing MCS table. Also, when the SNR is equal to or less than a second threshold, i.e., SNR low (830), the new MCS table can be configured with only the highest M indexes among the total N MCS indexes in the existing MCS table.

[0147] 1-2. Some indexes can be reused in the existing MCS table without defining a new MCS table. In this case, the number of bits of the MCS index can be changed according to the number of CCs scheduled by MC-DCI.

[0148] According to one embodiment, only even or odd indexes can be used in the existing MCS table. In this case, if MCS index 10 is indicated for a specific CC, index 10 can be mapped to MCS index 20, 21, or 19 in the existing MCS table.

[0149] According to one embodiment, an index that is a multiple of a certain number (e.g., 3 or 4) can be used depending on the number of scheduled CCs. That is, as the number of scheduled CCs increases, more bits per CC must be reduced, so only a smaller number of indexes can be mapped to the new index. This allows the number of MCS bits used per CC to be flexibly changed depending on the number of scheduled CCs.

[0150] 1-3. CCs that can be scheduled using MC-DCI are grouped into multiple groups, and the same MCS table and new mapping method can be applied to each group.

[0151] Among CCs to be scheduled, CCs within a band or CCs having RF frequency bands with similar characteristics can be grouped into the same group. The above-mentioned method of defining a new MCS table for CCs belonging to the same group or a method of selectively using an existing MCS index according to the number of CCs to be scheduled can be applied.

[0152] 1-3-2. If multiple groups exist, the MCS field of the MC-DCI may include a group ID.

[0153] 1-3-3. Cells using the same MCS table and the same index mapping scheme can be preset as one MCS group and notified to the terminal. For example, the MCS group as shown in Fig. 9 can be preset by RRC or semi-statically set by MAC and notified to the terminal.

[0154] FIG. 9 is a diagram illustrating an example of MCS grouping for multi-carrier scheduling in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 9, Pcell, Scell5, and Scell1 are included in MCS group 1 (910), Scell2, Scell3, and Scell4 are included in MCS group 2 (920), and Scell6, Scell7, and Scell8 are included in MCS group 3 (930). The same MCS table and index mapping method can be applied to cells belonging to the same MCS group. For example, Pcell, Scell5, and Scell1 in MCS group 1 (910) follow the same MCS table. Here, an MCS group can be understood as a cell group that uses the same MCS table.

[0155] 1-4. Some indexes of the MCS table are grouped into a new MCS index group, and an index for each MCS index group can be mapped to each CC.

[0156] FIG. 10 is a diagram illustrating an example of an MCS index group in multi-carrier scheduling in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 10, some index numbers in an existing MCS table can be set as a new MCS index group. For example, indexes 0, 2, 5, 7, 10, 12, 16, 20, and 05 in the existing MCS table can be set as MCS index group 1 (1010), and indexes 1, 3, 6, 8, 9, 14, 17, 18, 23, and 27 in the existing MCS table can be set as MCS index group 2 (1020). The new MCS index group can be preset by RRC. In this case, which index in the existing MCS table is included in one MCS index group can be determined according to the characteristics of CCs and the number of CCs. Furthermore, when multiple MCS index groups are set, the MCS field of the MC-DCI can further include a group ID.

[0157] Specifically, if the number of MCS indexes included in a full MCS table used in DCI for single-cell scheduling is N, the MCS information of a cell scheduled via MC-DCI may be indicated based on a reduced MCS table including M MCS indexes. Here, the MCS information of a cell scheduled via MC-DCI may include an MCS value for each of a plurality of cells and / or an MCS value for each TB transmitted via a PDSCH of a plurality of cells. The number M of MCS indexes of the reduced MCS table may have a value smaller than the number N of MCS indexes included in the full MCS table.

[0158] According to an embodiment, the M MCS indexes may be the lowest M indexes or the highest M indexes among the N MCS indexes in the existing complete MCS table. According to an embodiment, the M MCS indexes may be indexes corresponding to multiples of K among the N MCS indexes in the existing complete MCS table. Here, K may be 0 or a positive integer. For example, if K is 2, the M MCS indexes may be 2, 4, 6, 8, 10, ..., 30, which correspond to multiples of 2. According to an embodiment, the M MCS indexes may include indexes corresponding to multiples of K plus a specific offset among the N MCS indexes in the existing complete MCS table. For example, if K is 3 and the offset is 1, the M MCS indexes may be 4, 7, 10, 13, ..., 31. According to an embodiment, the M MCS indexes can be directly determined by the base station. The above-mentioned reduced MCS table can be applied to a case where multiple cells are scheduled using MC-DCI. The conventional complete MCS table can be applied when scheduling for one cell via MC-DCI or for each TB transmitted via PDSCH on one cell.

[0159] As described above, when an individual value is set for each cell and / or each TB in the MCS field in the MC-DCI for multi-cell scheduling, the size of the MCS field can be determined as follows.

[0160] First, the size of the MCS field in the DCI for the existing single cell scheduling can be set to L=ceil{log2(N)} bits. Here, the size of the MCS field may be a size set so that N (e.g., about 32) MCS states and / or MCS indices can be indicated via the MCS field. L may be set to the same value or different values ​​for cells. For example, L may be 5.

[0161] Meanwhile, when the MCS field in the MC-DCI for multi-cell scheduling includes an individual value for each cell and each TB, the maximum value of the multiple L_sums for each of the multiple co-scheduled cell sets can be determined as the size of the MCS field in the MC-DCI for multi-cell scheduling. Here, the co-scheduled cell set means a combination of cells scheduled together via the same MC-DCI. The co-scheduled cell set can be set based on a schedulable cell set via the MC-DCI. The schedulable cell set means a set including all cells that can be scheduled via the MC-DCI. Also, L_sum means the sum of the L values ​​for each TB according to the maximum transmittable TB number set for each cell belonging to the co-scheduled cell set.

[0162] For example, for a schedulable cell set {cell1, cell2, cell3}, two co-scheduled cell sets #1 and #2 can be set to {cell1, cell2} and {cell2, cell3}, respectively. In this case, if the number of maximum transmittable TBs for PDSCH and / or PUSCH set to cell1, cell2, and cell3 is 1, 1, and 2, respectively, and L is 5 bits, the L_sum of the co-scheduled cell set #1 is 10 bits, and the L_sum of the co-scheduled cell set #2 is 15 bits. Therefore, the size of the MCS field in the MC-DCI can be determined to be 15 bits.

[0163] Option 2: shared-common

[0164] The shared-common method is a method of applying the same MCS index to all of a plurality of CCs, or applying the same MCS index to CCs or cells belonging to a specific group. Here, CCs or cells belonging to a specific group may have the same group ID. In other words, the shared-common method is a method of providing one MCS index to a plurality of CCs, rather than providing an MCS index for each CC as in Option-1.

[0165] FIG. 11 is a diagram illustrating an example of cell groups using the same MCS index in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 11, a base station may group cells that can share the same MCS index among a plurality of cells into cell groups or cell subgroups using the same MCS, and transmit group IDs and MCS indexes via MC-DCI for scheduling of a plurality of cells. For example, MCS group 1 (1110) may include Pcell and Scell ​​2, and MCS group 2 (1120) may include Scell ​​1 and Scell ​​3. In this case, the base station may indicate MCS indexes for a plurality of CCs using a smaller number of bits than when transmitting MCS indexes for each CC. In this case, each cell group may be pre-configured in the RRC layer of the base station, or may be semi-statically configured in the MAC CE.

[0166] Specifically, the base station may configure an MCS field including one MCS index in the MC-DCI for scheduling for a plurality of cells. In this case, the MCS index indicated through the MCS field may be commonly applied to all of the plurality of cells or to all of the plurality of TBs transmitted through the PDSCH on the plurality of cells. As described above, in a state where a plurality of cell groups sharing one MCS field are set, the base station may configure and / or indicate a common MCS field and / or common MCS information for each cell group. The cell group sharing one MCS field may include cells to which the MCS index indicated through one MCS field in the MC-DCI is commonly applied. According to an embodiment, the MCS table corresponding to the common MCS field for each cell group may be configured in the form of a reduced MCS table as described above. In this case, whether or not to use MCS for URLCC is determined according to the RNTI, and a rule may be defined to restrict the cell group to be configured to be composed of cells capable of changing MCS in real time.

[0167] As described above, the base station can configure the MCS field in the MC-DCI by applying a shared-common scheme for each cell group or cell subgroup belonging to a co-scheduled cell set. That is, one MCS field is configured for each cell group / subgroup or for each TB index, and the MCS index indicated through one MCS field can be commonly applied to cells belonging to the cell group / subgroup or the TB.

[0168] A co-scheduled cell set may include at least one 1-TB cell and at least one 2-TB cell, where a 1-TB cell is a cell that transmits one TB via the PDSCH and a 2-TB cell is a cell that transmits two TBs via the PDSCH.

[0169] According to an embodiment, a rule may be defined to restrict a cell group to be composed of only 1-TB cells or only 2-TB cells. That is, when determining cells that belong to a cell set to be scheduled together, the base station may restrict 1-TB cells and 2-TB cells not to belong to the same cell group. If only 2-TB cells are included in a cell group, the base station may configure and / or indicate MCS fields and / or MCS information commonly applied to a plurality of cells for each TB index of the 2-TB cells. Alternatively, if only 2-TB cells are included in a cell group, the base station may configure and / or indicate MCS fields and / or MCS information commonly applied to all TB indexes of the 2-TB cells.

[0170] According to an embodiment, one cell group may be allowed to include a 1-TB cell and a 2-TB cell. That is, when determining cells that belong to a cell set to be scheduled together, the base station may include the 1-TB cell and the 2-TB cell in the same cell group. When the cell group includes the 1-TB cell and the 2-TB cell, the base station may configure and / or indicate a first MCS field and / or first MCS information commonly applied to the TB1 index on the 2-TB cell and the single TB on the 1-TB. Also, the base station may configure and / or indicate a second MCS field and / or second MCS information commonly applied to the TB2 index on the 2-TB cell. Alternatively, when the cell group includes the 1-TB cell and the 2-TB cell, the base station may configure or indicate an MCS field and / or MCS information commonly applied to all TB indexes of the 1-TB cell and the 2-TB cell.

[0171] A 1-table cell in which one MCS table is set and a 2-table cell in which two MCS tables are set can be included in a cell set to be scheduled together. A 1-table cell is a cell in which an MCS table indicated via a C-RNTI-based PDCCH is set, and a 2-table cell is a cell in which a first MCS table indicated via a C-RNTI-based PDCCH and a second MCS table indicated via an MCS-C-RNTI-based PDCCH are set.

[0172] According to one embodiment, a rule can be defined that restricts a cell group to be composed of only 1-table cells or only 2-table cells, i.e., when determining a set of cells to be scheduled together, the base station can restrict 1-table cells and 2-table cells not to belong to the same cell group.

[0173] According to one embodiment, it may be allowed for one cell group to include 1-table cells and 2-table cells, i.e., when determining a set of cells to be scheduled together, the base station may include 1-table cells and 2-table cells in the same cell group.

[0174] According to an embodiment, when a co-scheduled cell set includes both 1-table cells and 2-table cells, the base station may indicate an MCS index using MC-DCI in a C-RNTI-based PDCCH. That is, a rule may be defined that restricts scheduling by MC-DCI in an MCS-C-RNTI-based PDCCH not to be permitted for a co-scheduled cell set including both 1-table cells and 2-table cells.

[0175] According to an embodiment, for a jointly scheduled cell set including all 1-table cells and 2-table cells, scheduling via MC-DCI in MCS-C-RNTI-based PDCCH may be allowed. In this case, for the 1-table cells, the terminal may interpret and apply a value indicated in the MCS field in the MC-DCI as an MCS index of an MCS table corresponding to a C-RNTI-based PDCCH, or may consider or assume that there is no scheduling, and perform PDSCH and / or PUSCH transmission / reception.

[0176] According to an embodiment, one cell group may include 1-table cells and 2-table cells. That is, when determining a set of cells to be scheduled together, the base station may include 1-table cells and 2-table cells in the same cell group. If one cell group includes all 1-table cells and 2-table cells, the base station may indicate the MCS index using the MC-DCI in the C-RNTI-based PDCCH. That is, a rule may be defined that restricts scheduling via the MC-DCI in the MCS-C-RNTI-based PDCCH to be not permitted for a cell group including all 1-table cells and 2-table cells. According to an embodiment, if scheduling via the MC-DCI in the MCS-C-RNTI-based PDCCH is permitted for a cell group including all 1-table cells and 2-table cells, the base station and / or the terminal may consider or assume that there is no scheduling for the 1-table cells and perform PDSCH and / or PUSCH transmission / reception.

[0177] Option-3: Separate-equal between cells and shared-common between TBs

[0178] Two TBs, i.e., 2-TB, can be transmitted in one cell. When 2-TBs are transmitted in one cell, more data can be transmitted than when 1-TB is transmitted. This is a MIMO-related issue, and when 2-TBs are transmitted in one cell, an MCS index for each TB is required. Therefore, the present disclosure proposes a scheme to reduce the number of MCS bits for TBs of multiple cells while reducing the number of MCS bits for multiple cells.

[0179] 3-1. According to one embodiment, when the inter-cell option-1 scheme is applied and each cell uses 2-TB, the same MCS index can be applied to the two TBs.

[0180] If the difference in MCS index between 3-2.2-TB is not large, it can be handled by the internal implementation of the base station.

[0181] According to an embodiment, the maximum TB number for each cell may be preset by the base station, and the maximum TB number for each cell may be restricted by a higher layer. In this case, a rule for restricting cell grouping based on the TB number for each cell may be defined.

[0182] Specifically, the base station may apply the above-mentioned Option-2 scheme to two TBs transmitted via the same PDSCH of the same cell. That is, the base station may configure and / or indicate one shared MCS field and / or shared MCS information for the two TBs. Also, the base station may configure and / or indicate an individual shared MCS field and / or individual shared MCS information for each cell according to the Option-1 scheme. In this case, the MCS table corresponding to the individual shared MCS field may be a reduced MCS table.

[0183] According to an embodiment, the above-mentioned method can be applied when multiple cells are scheduled via MC-DCI, and when only one cell is scheduled via MC-DCI, an individual MCS value can be configured for each TB, and the individual MCS value for each TB can be indicated to the terminal. In this case, the MCS table corresponding to the individual MCS value for each TB can be a complete MCS table. Here, when the number of TBs of CCs in a group is different from each other, that is, when a 2-TB cell and a 1-TB cell belong to one group, only one of TB1 and TB2 of the 2-TB cell can be set to share an MCS field with the 1-TB cell. When the number of TBs of CCs in a group is the same, TBs having the same index can share the same MCS value.

[0184] According to one embodiment, the number of TBs of cells in a group may be limited to 1 or 2. This is to prevent an increase in complexity when scheduling many cells and many TBs together in a base station. That is, in order to reduce the scheduling complexity for multiple cells, the maximum number of TBs for each cell may be limited. In this case, cell grouping for multiple cells may be performed based on the maximum number of TBs.

[0185] Option 4: separate-delta

[0186] The above-mentioned Option-1 method does not use all the complete MCS table indexes, but only uses a part of them, and the Option-2 method does not reflect the difference between CCs and processes them averagely. However, when 5-bit MCS values ​​are connected in parallel and used, there is a possibility that a problem occurs in which the bit occupancy rate of the MCS field in MC-DCI increases excessively. Therefore, the present disclosure proposes a method of using the existing complete MCS index table as it is while reducing the amount of MCS information.

[0187] 4-1. A reference CC may be set in a higher layer, and delta information for the remaining CCs may be indicated via MC-DCI. In this case, the MCS information bits of the reference CC may be 5 bits, and the MCS information bits of the remaining CCs may be 3 bits.

[0188] 12 is a diagram showing an example of MCS-based delta operation of a reference CC in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 12, the reference CC of reference CC group 1 (1210) is Pcell (1211), and the reference CC of reference CC group 2 is Scell ​​3 (1221). Therefore, for the reference CCs Pcell (1211) and Scell ​​3 (1221), MCS indexes are indicated using 5 bits, and for the other CCs, i.e., Scell ​​2 and Scell ​​4 of reference CC group 1 (1210) and Scell ​​1 and Scell ​​5 of reference CC group 2 (1220), delta values ​​can be indicated using 2 bits or 3 bits, which is less than 5 bits.

[0189] 4-2. The base station may indicate the reference MCS index to the terminal via MAC CE or RRC, and may indicate delta information of all CCs using MC-DCI. Here, the delta information may represent the difference between the reference MCS index of the reference CC and each MCS index of the remaining CCs. According to one embodiment, the reference MCS index may be included in the MC-DCI. In this case, the MC-DCI may include 5-bit reference MCS index information and 3-bit delta information per CC.

[0190] FIG. 13 illustrates an example of delta operation based on a reference MCS in a wireless communication system according to an embodiment of the present disclosure. Referring to FIG. 13, unlike FIG. 12, there is no reference CC. That is, FIG. 13 illustrates a situation in which delta information is applied to all cells in a group. The delta information indicates the difference between the reference MCS index and the MCS index of each cell. The method of FIG. 13 can provide an effect of leveling the delta information value by setting the average MCS index of the cells in the group as the reference MCS index when the delta information value of the cells in the group becomes large.

[0191] 4-3. Information on CCs included in each group can be pre-configured by RRC or semi-statically notified to the terminal by MAC CE.

[0192] 4-4. In the above-mentioned embodiments 4-1 and 4-2, the delta information for the reference MCS index, i.e., the interval of the delta value, may be 1, but is not necessarily required to be 1. For example, the base station can notify the terminal in advance of a delta value range having a specific interval such as {-4, -2, 0, 2, 4} at a higher layer, and can instruct the terminal of the delta value, which is the difference from the reference MCS index, based on this. As another example, the delta value range can be {-5, -4, -1, 0, 1, 2, 3}. That is, the delta value range can be changed, and the delta values ​​can not have equal intervals.

[0193] According to an embodiment, the base station may configure and / or indicate an MCS field and / or MCS field information based on a complete MCS table for a specific reference cell among cells scheduled via MC-DCI. In this case, the specific reference cell may be set based on a cell index, an SCS, a CIF field, and an MC-DCI field. For example, a cell with the lowest cell index, a cell with the highest cell index, a cell set to have the lowest SCS, a cell set to have the highest SCS, a cell indicated by the CIF field, or a cell transmitting MC-DCI may be set as the reference cell.

[0194] When configuring and / or indicating an MCS field and / or MCS field information for a specific reference cell based on the complete MCS table, the base station may indicate, for the remaining cells, a relative offset value for the reference MCS index indicated in the MCS field of the reference cell. Thus, the terminal may apply, for the remaining cells, an MCS index corresponding to a value obtained by adding the relative offset value to the reference MCS index (hereinafter, "delta MCS"). In this case, the relative offset value for the remaining cells may be indicated in the range of 0 and a positive integer, in the range of 0 and a negative integer, or in the range of a negative integer and 0 and a positive integer. When multiple cell groups to which the delta MCS scheme is applied are configured, the base station may configure and / or indicate an MCS field and / or offset field for each cell group via the MC-DCI based on the delta MCS scheme.

[0195] Option-5: Separate-equal between cells and separate-delta between TBs

[0196] Option-5 applies the individual-equal method of Option-1 between cells and the individual-delta method of Option-4 between TBs. That is, this disclosure proposes a method to reduce the number of bits by setting one TB of the 2-TB as a reference TB and applying delta to the remaining TB.

[0197] 5-1. According to an embodiment, the MCS information of TB1 can be operated as 5 bits, and the MCS information of TB2 can be operated as 3 bits or 2 bits.

[0198] 5-2. According to one embodiment, the delta information for the reference MCS index between TBs, i.e., the interval of the delta value, may be 1, but is not necessarily required to be 1. For example, a delta value range having a specific interval such as {-4, -2, 0, 2, 4} may be notified to the terminal from a higher layer in advance, and a delta value, which is the difference from the reference MCS index, may be indicated based on this. As another example, the delta value range may be {-5, -4, -1, 0, 1, 2, 3}. That is, the delta value range may be changed, and the delta values ​​may not have equal intervals.

[0199] According to an embodiment, the base station may configure and / or indicate MCS field and / or MCS field information based on the delta MCS scheme for two TBs transmitted through the same PDSCH in the same cell among cells scheduled through MC-DCI by applying the individual-delta scheme of Option-4. In this case, the base station may configure and / or indicate individual MCS field and / or offset field for each cell by applying the individual-uniform scheme of Option-1 for each cell. According to an embodiment, the MCS field and / or MCS information based on the complete MCS table may be configured and / or indicated for a specific TB index (e.g., the lowest TB index) among two TBs transmitted through the same PDSCH in the same cell, and a relative offset value for the MCS index indicated through the MCS field of the specific TB index may be indicated for the remaining TB indexes. The above-mentioned Option-5 may be applied when multiple cells are scheduled through MC-DCI. When only one cell is scheduled through MC-DCI, individual MCS field and / or MCS field information may be configured and / or indicated for each TB. That is, when only one cell is scheduled via MC-DCI, the delta MCS scheme is not applied, and individual MCS fields and / or MCS field information based on the complete MCS table can be configured and / or indicated.

[0200] Option 6: Various other additional indications and scheduling configuration methods

[0201] 6-1. The base station can semi-statically notify and / or set cell-specific MCS information to the terminal via the MAC CE. In this case, the terminal can decode the PDSCH for the cell triggered by the MC-DCI based on the cell-specific MCS information previously acquired via the MAC CE.

[0202] 6-2.Since MCS information is included in TB information, the amount of information required for MCS transmission varies depending on the number of TBs to be transmitted. In particular, the total number of bits required for full MCS transmission may be determined depending on whether there is one or two TBs per CC. In this case, the total number of TBs as well as the number of CCs scheduled in the PDCCH may be signaled in advance in a higher layer. That is, the number of MCSs to be indicated may be reduced by limiting the total number of CCs and the total number of TBs. As the number of MCSs is reduced, the number of bits used for MCS indication may also be reduced.

[0203] In MC-DCI, the MCS field and / or at least one of the fields is set for each cell or cell group. In this case, the remaining fields except the field set for the reference CC can be mapped based on the CIF bit. The reference CC can be indicated via a higher layer or DCI. The CIF bit order can be determined based on the cell or cell group. The MCS information of the reference CC can be placed at the front of the field.

[0204] 6-4. The base station can indicate the number of CCs to be scheduled via the CIF. If information of a particular cell is not included in the MC-DCI, the base station can indicate that the cell is not actually scheduled in the cell group or scheduled CC by indicating any of the three CIF bits as 0. If the CIF bit is 1, the MCS information of the reference CC is reused for the cell as is. In this case, the cell group, rather than the cell, can be mapped to the CIF three bits.

[0205] According to one embodiment, since the CIF is composed of 3 bits, it is possible to indicate the validity of three cell groups or three cells using the CIF, so that whether to indicate the MCS in a shared manner or in a separate manner can follow the above-mentioned options.

[0206] According to one embodiment, at least one field that can be shared among cells in a cell group is used in principle by the cells in question.

[0207] 6-5. Cells scheduled via MC-DCI can be classified into 1-TB cells with a maximum TB number of 1 and 2-TB cells with a maximum TB number of 2 via MC-RNTI. Classification of RNTI according to the maximum TB number can also be applied to MCS-MC-RNTI and MC-CS-RNTI.

[0208] 6-5-1. Multiple MC-CS-RNTIs can be configured in a higher layer based on the maximum number of TBs available in each cell. The MC-CS-RNTIs can be grouped according to the maximum number of TBs in a scheduled CC.

[0209] 6-5-2. Multiple MC-CS-RNTIs can be configured for the MC-DCI field, scheduled cells, cell groups, etc., and MC-RNTIs and C-RNTIs, etc. can be mixed for a single cell, multiple cells, DG (dynamic grant) and / or CG (configured grant).

[0210] 6-6. The base station can set the maximum number of bits of the MCS that can be transmitted in one MC-DCI, and determine the number of independent MCSs that can be transmitted based on the maximum number of bits.

[0211] 6-6-1. For example, if the maximum number of MCS bits that can be transmitted in one MC-DCI is 10 bits, the number of MCS values ​​that can be transmitted can be determined within a range not exceeding 10 bits. Thus, the base station can set an MCS value in the MCS field within a range not exceeding the maximum number of bits in the MC-DCI, and discard a portion exceeding the maximum number of bits. According to an embodiment, regardless of which of the above-mentioned options is used, a rule can be defined that restricts the MCS bits set in the MCS field not to exceed a preset maximum number of MCS bits. According to an embodiment, the base station can control a specific field in the DCI not to occupy too many bits from a scheduling perspective.

[0212] According to one embodiment, for a field in DCI other than MCS that must be individually signaled for each cell or cell group, a higher layer (e.g., RRC layer or MAC layer) may preset the maximum number of bits to be used for the field. By presetting the maximum number of bits to be used for the field, information of a cell that belongs to a portion that exceeds the maximum number of bits to be used can be discarded. That is, by controlling a specific field in DCI so that it does not exceed the maximum number of bits to be used, it is possible to prevent an excessive number of bits from being used by a specific field.

[0213] 6-6-3. According to one embodiment, if a particular field is discarded, the schedule for that cell may be considered as not valid.

[0214] 6-7. The CIF can indicate the scheduled CC starting cell ID (CellID) index in the context of multi-carrier aggregation. In the MC-DCI, the number of cells to be scheduled consecutively after the starting cell ID index can be preset by a higher layer. For example, if the number of scheduled CCs is 4 and the starting cell ID index is 3, then cells with cell ID indexes 4, 5, and 6 can be scheduled together. In this case, the availability of an additional RA or other one-bit information (e.g., VRB-PRB-mapping, etc.) can indicate that a particular cell is not actually scheduled.

[0215] 6-8. The method of dividing the TB of the CBG (code block group) for URLLC may not be used because the complexity is too high in multi-cell scheduling and there are problems with HARQ processing between each cell.

[0216] 6-9. In a state where grouping of multiple cells is not performed, scheduling can be performed based on the number of CCs. In this case, if two MCS tables are set for some cells among multiple CCs and one MCS table is set for other cells, various methods can be applied to process MCS-MC-RNTI.

[0217] 6-9-1: For a cell with one MCS configured, the cell can be treated as not scheduled.

[0218] 6-9-2: A cell with one MCS configured can be processed to be scheduled with only one MCS table.

[0219] 6-10. In the case where there is one cell group or cell subgroup, four cells are scheduled at the same time, and the maximum number of transmission TBs of each cell is two, the MCS occupies five bits per TB, occupying a total of 40 bits (=4×2×5) in the MC-DCI. That is, since the MCS occupies too many bits in the MC-DCI, a method of using one MCS value for a cell with two TBs can be applied. That is, the two TBs in a cell can be set to share an MCS value. In this case, for a cell with two TBs, the MCS information for the 2-TB of the cell can be indicated by only five bits in the MCS field of the MC-DCI.

[0220] 6-10-1: In general, the number of bits for the entire cell of the MCS field in the MC-DCI can be calculated by the product of the sum of the number of TBs of each cell in a combination having the maximum number of simultaneously scheduled CCs and the specified number of bits (e.g., 5 bits). However, if the TBs in a cell share an MCS, the bit size for the entire cell of the MCS field in the MC-DCI can be calculated by the product of the number of the maximum simultaneously scheduled CCs and the specified number of bits.

[0221] 6-10-2: When MCS sharing is preset, only 5-bit MCS information can be set for the corresponding cell in MC-DCI. In this case, in the case of 1-TB, 5-bit MCS information is applied to 1-TB, and in the case of 2-TB, 5-bit MCS information can be commonly applied to each of the two TBs.

[0222] 6-11. The base station determines the MCS field size in the MC-DCI, i.e., the total number of MCS bits, as N (= 5 bits x the sum of the number of TBs of the cell), and can notify and / or set the determined MCS field size in advance to the terminal via RRC signaling.

[0223] 6-11-1. The MCS field size may be predefined to 20 bits. In this case, if MCS sharing is not configured and at least one cell uses 2-TB, the MCS of some cells may not be indicated.

[0224] 6-11-2. When MCS sharing is set, the MCS field can be configured based on the TB order or cell order as shown in Figures 14 and 15. Figures 14 and 15 show an example of the structure of the MCS field of the MC-DCI in a wireless communication system according to an embodiment of the present disclosure. Specifically, Figures 14 and 15 illustrate the structure of the MCS field of the MC-DCI in a situation where the size of the MCS field is set to a maximum of 5x5 bits or 7x5 bits, and the TBs of the cells scheduled together in the MC-DCI are cell A: 2-TB, cell B: 2-TB, cell C: 1-TB, and cell D: 2-TB. In Figures 14 and 15, the 2-TBs of cell A are referred to as aTB1 and aTB2, the 2-TBs of cell B are referred to as bTB1 and bTB2, the 1-TB of cell C is referred to as cTB1, and the 2-TBs of cell D are represented by dTB1 and dTB2. FIG. 14 shows an example in which TB-specific MCS information is added to the MCS field based on the cell order, and FIG. 15 shows an example in which TB-specific MCS information is added to the MCS field based on the TB order.

[0225] 14, when the maximum MCS field size is set to 7×5 bits, the MCS field can include MCS for aTB1 1411, MCS for aTB2 1412, MCS for bTB1 1421, MCS for bTB2 1422, MCS for cTB1 1431, MCS for dTB1 1441, and MCS for dTB2 1442. That is, when the maximum MCS field size is set to 7×5 bits, MCS scheduling for all cells that must be scheduled simultaneously is possible.

[0226] According to one embodiment, when the maximum MCS field size is 6×5 bits, the MCS field can include MCS 1411 of aTB1, MCS 1412 of aTB2, MCS 1421 of bTB1, MCS 1422 of bTB2, MCS 1431 of cTB1, and MCS 1441 of dTB1. In this case, the MCS field does not include MCS 1442 of dTB2, which is the second TB of cell D, but if MCS sharing is configured, MCS 1441 of dTB1 can also be used as MCS 1442 of dTB2.

[0227] According to one embodiment, when the maximum MCS field size is set to 5×5 bits, the MCS field can include MCS 1411 for aTB1, MCS 1412 for aTB2, MCS 1421 for bTB1, MCS 1422 for bTB2, and MCS 1431 for cTB1. In this case, the MCS field does not include MCSs 1441 and 1442 for the two TBs of cell D. That is, due to the limitation of the maximum MCS field size, no scheduling is performed for cell D.

[0228] 15, when the maximum MCS field size is set to 7×5 bits, the MCS field can include MCS 1511 of aTB1, MCS 1521 of bTB1, MCS 1531 of cTB1, MCS 1541 of dTB1, MCS 1512 of aTB2, MCS 1522 of bTB2, and MCS 1542 of dTB2. That is, when the maximum MCS field size is set to 7×5 bits, MCS scheduling for all cells that must be scheduled simultaneously is possible.

[0229] According to one embodiment, when the maximum MCS field size is 6×5 bits, the MCS field can include MCS 1511 of aTB1, MCS 1521 of bTB1, MCS 1531 of cTB1, MCS 1541 of dTB1, MCS 1512 of aTB2, and MCS 1522 of bTB2. In this case, since the MCS field does not include MCS 1542 of dTB2, which is the second TB of cell D, but includes MCS 1541 of dTB1, which is the first TB of cell D, when MCS sharing is configured, MCS 1541 of dTB1 can also be used as MCS 1542 of dTB2.

[0230] According to an embodiment, when the maximum MCS field size is set to 5×5 bits, the MCS field may include MCS 1511 of aTB1, MCS 1521 of bTB1, MCS 1531 of cTB1, MCS 1541 of dTB1, and MCS 1512 of aTB2. In this case, the MCS field does not include MCS 1522 of bTB2, which is the second TB of cell B, and MCS 1542 of dTB2, which is the second TB of cell D, but includes MCS 1521 of bTB1, which is the first TB of cell B, and MCS 1541 of dTB1, which is the first TB of cell D. Therefore, when MCS sharing is set, MCS 1521 of bTB1 and MCS 1541 of dTB1 can be used as MCS 1522 of bTB2 and MCS 1542 of dTB2, respectively.

[0231] Among the situations described with reference to Figure 15, there are no cells that cannot be scheduled via the MCS field in the MC-DCI. Therefore, depending on the situation, the scheme of Figure 15 may be more advantageous than the scheme of Figure 14. That is, when MCS sharing is configured, the MCS value in the MCS field is shared between different TBs, so that it may be effective to configure the MCS field as in Figure 15 in a situation where the number of TBs can be dynamically changed in the MIMO layer.

[0232] As described above, multi-carrier scheduling can be performed according to various embodiments. For multi-carrier scheduling, MC-DCI can be used, and MC-DCI includes at least one field including coding rate and modulation order information, i.e., MCS information, for multiple CCs. Hereinafter, the operation of a base station and a terminal performing multi-carrier scheduling according to the above-mentioned embodiments will be described with reference to the drawings.

[0233] 16 is a diagram illustrating an example of a frequency domain resource information acquisition procedure in a wireless communication system according to an embodiment of the present disclosure. FIG. 16 illustrates an operation method of a base station.

[0234] Referring to FIG. 16, in step S1601, the base station performs a connection establishment procedure for a primary cell. After the terminal connects to the base station, the base station performs a connection establishment procedure with the terminal. To this end, the base station may receive a setup request message for connection from the terminal and transmit a setup complete message. Although not shown in FIG. 16, prior to step S1601, the base station may perform an initial access procedure by receiving a random access preamble from the terminal and transmitting a random access response (RAR) message.

[0235] In step S1603, the base station performs a connection establishment procedure for at least one secondary cell. After the connection for the primary cell of the terminal is established, the base station performs an additional connection establishment procedure with the terminal. To this end, the base station may receive a reconfiguration message for the connection from the terminal and transmit a reconfiguration complete message. As a result, one primary cell and at least one secondary cell between the base station and the terminal may be established. Also, although not shown in FIG. 16, the base station may transmit a MAC CE for activating at least one secondary cell.

[0236] In step S1605, the base station transmits DCI. Here, the DCI may include information for multi-carrier scheduling. That is, the base station allocates resources of a plurality of cells to the terminal, generates DCI indicating the allocated resources, and transmits the DCI to the terminal via one of the plurality of cells. For example, the DCI may include information indicating resources allocated in a plurality of cells including one primary cell and at least one secondary cell. In this case, MCS information for each cell and / or each TB may be indicated according to the various embodiments described above. Depending on the case, resources may not be allocated in some of the plurality of cells. In this case, the DCI may include information indicating at least one cell to which resources are not allocated, i.e., which is not actually scheduled.

[0237] In step S1607, the base station transmits or receives data through multiple cells. The base station can transmit or receive data through resources of multiple cells indicated by the DCI. If downlink resources are allocated by the DCI, the base station transmits data. To this end, the base station can perform channel coding, scrambling, rate matching, quality mapping, resource mapping, layer mapping, waveform modulation, etc. If uplink resources are allocated by the DCI, the base station receives data. To this end, the base station can perform waveform demodulation, quality demapping, channel decoding, etc.

[0238] 17 is a diagram illustrating an example of a frequency domain resource information transmission procedure in a wireless communication system according to an embodiment of the present disclosure. FIG. 17 illustrates an operation method of a terminal.

[0239] Referring to FIG. 17, in step S1701, the terminal performs a connection establishment procedure for a primary cell. After the terminal connects to the base station, the terminal performs a connection establishment procedure with the base station. To this end, the terminal can transmit a setting request message for connection to the base station and receive a setting completion message. Although not shown in FIG. 17, prior to step S1701, the terminal can transmit a random access preamble to the base station and receive a random access response message to perform an initial access procedure.

[0240] In step S1703, the terminal performs a connection establishment procedure for at least one secondary cell. After the connection for the primary cell of the terminal is established, the terminal performs an additional connection establishment procedure with the base station. To this end, the terminal can transmit a reconfiguration message for connection to the base station and receive a reconfiguration completion message. As a result, one primary cell and at least one secondary cell between the base station and the terminal can be established. Also, although not shown in FIG. 17, the terminal can receive a MAC CE for activating at least one secondary cell.

[0241] In step S1705, the terminal receives DCI. Here, the DCI may include information for multi-carrier scheduling. That is, the terminal may check the result of multi-carrier scheduling through the DCI. For example, the DCI may include information indicating resources allocated in a plurality of cells including one primary cell and at least one secondary cell. In this case, MCS information for each cell and / or each TB may be indicated according to the various embodiments described above. In some cases, resources may not be allocated in some of the plurality of cells. In this case, the DCI may include information indicating at least one cell to which resources are not allocated, i.e., which is not actually scheduled.

[0242] In step S1707, the terminal receives or transmits data through multiple cells. The terminal can receive or transmit data through resources of multiple cells indicated by the DCI. If downlink resources are allocated by the DCI, the terminal receives data. To this end, the terminal can perform waveform demodulation, quality demapping, channel decoding, etc. If uplink resources are allocated by the DCI, the terminal transmits data. To this end, the terminal can perform channel coding, scrambling, rate matching, quality mapping, resource mapping, layer mapping, waveform modulation, etc.

[0243] Fig. 18 illustrates an example of a procedure for indicating a resource allocation status using a radio network temporary identifier (RNTI) in a wireless communication system according to an embodiment of the present disclosure. Fig. 18 illustrates a signal exchange between a terminal 1810 and a base station 1820. In Fig. 18, the base station 1820 is described as providing two cells 1822-1 and 1822-2, but the procedure described below can also be applied to a situation in which three or more cells are provided.

[0244] Referring to FIG. 18, in step S1801, a base station 1820 transmits configuration information regarding an RNTI for an alternative MCS table to a terminal 1810. Here, the alternative MCS table is an additional MCS table different from a default MCS table, and can be allowed to be used by the terminal 1810 according to a configuration of the base station 1820. The configuration information includes information (e.g., an RNTI value) related to an RNTI (e.g., MCS-C-RNTI) for indicating the use of an alternative MCS table, and may include an IE (e.g., PhysicalCellGroupConfig) of an RRC layer. In this embodiment, the RNTI for the alternative MCS table is configured for a first cell 1822-1 and is not configured for a second cell 1822-2.

[0245] In step S1803, the base station 1820 allocates resources of the first cell 1822-1 to the terminal 1810, and does not allocate resources of the second cell 1822-2. Here, the first cell 1822-1 and the second cell 1822-2 are CCs configured in the terminal 1810 by carrier aggregation, and one of the first cell 1822-1 and the second cell 1822-2 is a primary cell, and the other is a secondary cell. At this time, the first cell 1822-1 and the second cell 1822-2 are in a state where they are configured to be scheduled using one DCI (e.g., MC-DCI) through multi-carrier scheduling. In addition, an RNTI for an alternative MCS table is configured for the first cell 1822-1, and an RNTI for an alternative MCS table is not configured for the second cell 1822-2.

[0246] In step S1805, the base station 1820 generates DCI for the first cell 1822-1 and the second cell 1822-2. Then, the base station 1820 scrambles the generated DCI using the RNTI for the alternative MCS table. Scrambling using the RNTI for the alternative MCS table indicates application of the alternative MCS table. That is, the DCI includes information indicating application of the alternative MCS table. Here, the alternative MCS table may be predefined or may be set via signaling for RNTI setting or separate signaling.

[0247] In step S1807, the base station 1820 transmits DCI to the terminal 1810. That is, the base station 1820 transmits information related to the resources allocated in step S1801. At this time, the DCI is in a state where it is scrambled using the RNTI for the alternative MCS table set for the first cell 1822-1. As a result, the transmitted DCI can be interpreted as indicating that resources are not allocated, i.e., that scheduling is not actually performed, for a cell in which the RNTI for the alternative MCS table is not set. In other words, the DCI transmitted in this step includes information indicating that resources of the second cell 1822-2 are not allocated, i.e., that scheduling is not actually performed in the second cell 1822-2.

[0248] In step S1809, the terminal 1810 confirms that resources of the second cell 1822-2 are not allocated. The terminal 1810 receives the DCI and attempts to decode the DCI using at least one RNTI. As a result, the terminal 1810 can confirm that decoding is successful using the RNTI for the alternative MCS table and determine that the alternative MCS table is applied. As a result, it can be confirmed that the terminal 1810 is not actually scheduled for a cell in which the RNTI for the alternative MCS table is not set, i.e., the second cell 1822-2. Then, the terminal 1810 confirms the resources allocated in the first cell 1822-1 via the DCI.

[0249] In step S1807, the base station 1820 transmits data via resources of the first cell 1822-1 to the terminal 1810. In other words, the base station 1820 transmits a signal including data via the PDSCH of the first cell 1822-1 to the terminal 1810. At this time, the PDSCH is mapped to resources indicated by the DCI transmitted in step S1805.

[0250] 19 illustrates an example of a procedure for performing multi-carrier scheduling according to a separate-equal scheme in a wireless communication system according to an embodiment of the present disclosure. FIG. 19 illustrates a signal exchange between a terminal 1910 and a base station 1920.

[0251] 19, in step S1901, the base station 1920 performs scheduling. The base station 1920 provides the terminal 1910 with the first cell 1922-1 to the Nth cell 1922-N using carrier aggregation, and performs scheduling for communication using the resources of the first cell 1922-1 to the Nth cell 1922-N. As a result, the resources of each of the first cell 1922-1 to the Nth cell 1922-N can be assigned to the terminal 1910.

[0252] In step S1903, the base station 1920 sets an MCS table and determines an MCS field size. The MCS table is set based on the complete MCS table. Here, the complete MCS table can be understood as an MCS table used for single carrier scheduling. For example, the base station 1920 can set a new MCS table including a part of the MCS index included in the complete MCS table. Then, the base station 1920 determines the MCS field size. For example, the base station 1920 can determine the size of the MCS field based on at least one of the set MCS table, the number of cells to be scheduled, and the number of TBs of each cell. In another embodiment, the MCS table can be set prior to the scheduling in step S1901.

[0253] In step S1905, the base station 1920 transmits DCI via resources of the first cell 1922-1. Here, the DCI includes a cell-specific MCS value. That is, the base station 1920 generates an MCS value for each of the multiple cells 1922-1 to 1922-N. The MCS value for each cell indicates one of the indexes in the MCS table set in step S1903. According to an embodiment, if at least one cell among the cells 1922-1 to 1922-N included in the group is not actually scheduled, the DCI may further include information indicating at least one cell that is not actually scheduled, i.e., invalid. For example, a value indicating an index not included in the MCS table can be used as information indicating an invalid cell.

[0254] In step S1907, the base station 1920 transmits data using resources of the first cell 1922-1 to the Nth cell 1922-N. The terminal 1910 can confirm the coding rate and modulation order applied to the data transmitted from each of the first cell 1922-1 to the Nth cell 1922-N based on the MCS value included in the DCI. As a result, the terminal 1910 can perform quality demapping and channel decoding on the signals received from each of the first cell 1922-1 to the Nth cell 1922-N.

[0255] 20 is a diagram illustrating an example of a procedure for performing multi-carrier scheduling according to a shared-common scheme in a wireless communication system according to an embodiment of the present disclosure. FIG. 20 illustrates signal exchange between a terminal 2010 and a base station 2020.

[0256] 20, in step S2001, the base station 2020 performs scheduling. The base station 2020 provides the first cell 2022-1 to the Nth cell 2022-N to the terminal 2010 using carrier aggregation, and performs scheduling for communication using the resources of the first cell 2022-1 to the Nth cell 2022-N. As a result, the resources of each of the first cell 2022-1 to the Nth cell 2022-N can be assigned to the terminal 2010.

[0257] In step S2003, the base station 2020 determines an MCS value shared among the cells 2022-1 to 2022-N. In other words, the base station 2020 determines a common MCS value for all the cells 2022-1 to 2022-N. To determine the common MCS value, the base station 2020 can jointly consider channel information collected from each of the cells 2022-1 to 2022-N. Here, the shared MCS value is shared among the cells scheduled together, and the cells scheduled together can be set before or after the execution of step S2001. If necessary, although not shown in FIG. 20, the base station 2020 can transmit information indicating the cells sharing the common MCS value to the terminal 2010.

[0258] In step S2005, the base station 2020 transmits DCI via the resources of the first cell 2022-1. In other words, the base station 2020 transmits DCI via the PDCCH of the first cell 2022-1. Here, the DCI includes the shared MCS value generated in step S2003. That is, the DCI may include resource allocation results for each of the cells 2022-1 to 2022-N and commonly applied MCS information. Or, if a plurality of groups are formed, the DCI may further include identification information for the group. If at least one cell among the cells 2022-1 to 2022-N included in the group is not actually scheduled, the DCI may further include information indicating at least one cell that is not actually scheduled, i.e., invalid.

[0259] In step S2007, the base station 2020 transmits data using resources of the first cell 2022-1 to the Nth cell 2022-N. The terminal 2010 can check the coding rate and modulation order applied to the data transmitted from each of the first cell 2022-1 to the Nth cell 2022-N based on the MCS value included in the DCI. As a result, the terminal 2010 can perform quality demapping and channel decoding on the signals received from each of the first cell 2022-1 to the Nth cell 2022-N.

[0260] 21 illustrates an example of a procedure for performing multi-carrier scheduling according to the shared-common method between cells and the individual delta method between TBs in a wireless communication system according to an embodiment of the present disclosure. FIG. 21 illustrates signal exchange between a terminal 2110 and a base station 2120.

[0261] 21, in step S2101, the base station 2121 performs scheduling. The base station 2121 provides the first cell 2122-1 to the Nth cell 2122-N to the terminal 2110 using carrier aggregation, and performs scheduling for communication using the resources of the first cell 2122-1 to the Nth cell 2122-N. As a result, the resources of each of the first cell 2122-1 to the Nth cell 2122-N can be allocated to the terminal 2110.

[0262] In step S2103, the base station 2121 determines an MCS value shared between TBs of each cell. In other words, the base station 2121 determines an MCS value for each of the cells 2122-1 to 2122-N, and each MCS value is commonly applied between the TBs in the cell. That is, the base station 2121 determines one MCS value per cell, which is shared between the TBs for each of the cells 2122-1 to 2122-N. For this reason, the base station 2121 can set an MCS table including a part of the MCS index included in the complete MCS table for the individual-uniform method between the cells 2122-1 to 2122-N, and determine the MCS field size. At this time, since the MCS value is shared between the TBs, the number of TBs may not be taken into consideration when determining the MCS field size.

[0263] In step S2105, the base station 2121 transmits DCI via the resources of the first cell 2122-1. In other words, the base station 2121 transmits DCI via the PDCCH of the first cell 2122-1. Here, the DCI includes an MCS value shared between the TBs of each cell generated in step S2103. That is, the DCI may include resource allocation results for each of the cells 2122-1 to 2122-N and MCS information commonly applied between the TBs in each cell. Or, if a plurality of groups are formed, the DCI may further include identification information for the group. If at least one cell among the cells 2122-1 to 2122-N included in the group is not actually scheduled, the DCI may further include information indicating at least one cell that is not actually scheduled, i.e., invalid.

[0264] In step S2107, the base station 2121 transmits data using resources of the first cell 2122-1 to the Nth cell 2122-N. The terminal 2110 can confirm the coding rate and modulation order applied to the data transmitted from each of the first cell 2122-1 to the Nth cell 2122-N based on the MCS value included in the DCI. As a result, the terminal 2110 can perform quality demapping and channel decoding on the signals received from each of the first cell 2122-1 to the Nth cell 2122-N.

[0265] 22 is a diagram illustrating an example of a procedure for performing multi-carrier scheduling according to a separate-delta scheme in a wireless communication system according to an embodiment of the present disclosure. FIG. 22 illustrates a signal exchange between a terminal 2210 and a base station 2220.

[0266] 22, in step S2221, the base station 2222 performs scheduling. The base station 2222 provides the terminal 2210 with the first cell 2222-1 to the Nth cell 2222-N using carrier aggregation, and performs scheduling for communication using the resources of the first cell 2222-1 to the Nth cell 2222-N. As a result, the resources of each of the first cell 2222-1 to the Nth cell 2222-N can be assigned to the terminal 2210.

[0267] In step S2223, the base station 2222 generates an MCS value for a reference cell. To this end, the base station 2222 can determine a group of cells to be scheduled together using one PDCCH, and select a reference cell from among the cells belonging to the group. In this embodiment, the first cell 2222-1 to the N-th cell 2222-N are grouped into one group. For example, the reference cell can be selected based on at least one of a cell index, a bandwidth, a channel quality, an SCS, and other DCI fields. Then, the base station 2222 can generate an MCS value for the reference cell.

[0268] In step S2225, the base station 2222 generates a delta value for at least one remaining cell. That is, the base station 2222 generates information capable of indicating an MCS index to be applied to other cells by being combined with the MCS value for the reference cell generated in step S2223. The delta value is generated for each remaining cell excluding the reference cell, and can indicate an index difference with respect to the MCS value of the reference cell. In this case, index difference candidates that can be indicated by the delta value can be preset, and the index difference candidates can be set to have equal intervals or unequal intervals.

[0269] In step S2227, the base station 2222 transmits the DCI via the resource of the first cell 2222-1. In other words, the base station 2222 transmits the DCI via the PDCCH of the first cell 2222-1. Here, the DCI includes the MCS value generated in step S2223 and at least one delta value generated in step S2225. Or, if a plurality of groups are formed, the DCI may further include identification information for the group. If at least one cell among the cells 2222-1 to 2222-N included in the group is not actually scheduled, the DCI may further include information indicating at least one cell that is not actually scheduled, i.e., invalid. Also, the DCI may further include information indicating a reference cell.

[0270] In step S2209, the base station 2121 transmits data using resources of the first cell 2122-1 to the Nth cell 2122-N. The terminal 2110 can confirm the coding rate and modulation order applied to the data transmitted from each of the first cell 2122-1 to the Nth cell 2122-N based on the MCS value and at least one delta value included in the DCI. Thus, the terminal 2110 can perform quality demapping and channel decoding on the signals received from each of the first cell 2122-1 to the Nth cell 2122-N.

[0271] According to the embodiment described with reference to FIG. 22, an MCS value for a reference cell and at least one delta value for at least one other cell are transmitted. Here, the MCS value for the reference cell is used as a reference for determining an MCS value of the at least one other cell based on the at least one delta value. According to another embodiment, the MCS value used for determining the MCS value of the at least one other cell may be determined without a reference cell. For example, the reference MCS value may be a predefined value or may be determined based on the MCS values ​​of the cells 2122-1 to 2122-N. In this case, the MCS value for the reference cell is not transmitted, and a delta value for each of the cells 2122-1 to 2122-N may be transmitted.

[0272] 23 illustrates an example of a procedure for performing multi-carrier scheduling according to the individual-equal scheme between cells and the individual-delta scheme between TBs in a wireless communication system according to an embodiment of the present disclosure. FIG. 23 illustrates signal exchange between a terminal 2310 and a base station 2320.

[0273] 23, in step S2301, the base station 2323 performs scheduling. The base station 2323 provides the first cell 2322-1 to the Nth cell 2322-N to the terminal 2310 using carrier aggregation, and performs scheduling for communication using the resources of the first cell 2322-1 to the Nth cell 2322-N. As a result, the resources of each of the first cell 2322-1 to the Nth cell 2322-N can be assigned to the terminal 2310.

[0274] In step S2303, the base station 2323 determines an MCS value shared between TBs of each cell. That is, the base station 2323 determines MCS information for each of the cells 2322-1 to 2322-N, where the MCS information includes a reference MCS value and at least one delta value for the TB of the cell. That is, the base station 2323 determines an MCS value for one of the TBs for each of the cells 2322-1 to 2322-N, and determines at least one delta value for at least one remaining TB. To this end, the base station 2323 may set an MCS table including a part of the MCS index included in the complete MCS table and determine an MCS field size for the individual-uniform scheme between the cells 2322-1 to 2322-N.

[0275] In step S2305, the base station 2323 transmits DCI via the resources of the first cell 2322-1. In other words, the base station 2323 transmits DCI via the PDCCH of the first cell 2322-1. Here, the DCI is cell-specific MCS information generated in step S2303, and includes a reference MCS value for the TB and at least one delta value. That is, the DCI may include MCS information including a resource allocation result for each of the cells 2322-1 to 2322-N and a reference MCS value and at least one delta value applied to the TB of each cell. Or, if a plurality of groups are formed, the DCI may further include identification information for the group. If at least one cell among the cells 2322-1 to 2322-N included in the group is not actually scheduled, the DCI may further include information indicating at least one cell that is not actually scheduled, i.e., invalid.

[0276] In step S2307, the base station 2323 transmits data using resources of the first cell 2322-1 to the Nth cell 2322-N. The terminal 2310 can confirm the coding rate and modulation order applied to the data transmitted from each of the first cell 2322-1 to the Nth cell 2322-N based on the cell-specific reference MCS value and at least one delta value included in the DCI. Thus, the terminal 2310 can perform quality demapping and channel decoding on the signals received from each of the first cell 2322-1 to the Nth cell 2322-N.

[0277] Multi-carrier scheduling may be performed according to the various procedures described above. The procedures described with reference to Figs. 19 to 23 are examples of procedures using a shared-common scheme, an individual-delta scheme, an individual-equal scheme, or a combination of two or more of these. However, the procedures described above may be jointly applied to each other. Furthermore, various embodiments described in the various options (e.g., option-1 to option-5) above may be combined with the procedures described above. Thus, multi-carrier scheduling according to various embodiments of the present disclosure may be modified in more diverse ways.

[0278] As the technology evolves and develops to 5G NR, the frequency bands that can be simultaneously transmitted using carrier aggregation have diversified to 6 GHz or more, or mmWave 20 GHz, 30 GHz, 60 GHz, and 100 GHz, and the number of cells that are operated simultaneously has increased significantly. In the previous 4G system, the principle was that one PDCCH, i.e., DCI, was generally transmitted at least once for one PDSCH transmission from one cell, regardless of whether the method was a self-scheduling method or a cross-carrier scheduling method. If the number of PDSCHs transmitted simultaneously was small, the burden of multiple decodes of the PDCCHs would not be large. However, if many PDCCHs must be decoded above a certain level, this may not only affect the performance of the terminal, but also consume a lot of frequency and time resources. Therefore, resources for traffic transmission may be reduced.

[0279] Therefore, a method of scheduling PDSCHs of multiple cells using one PDCCH is preferable. However, due to the limit of the maximum amount of information available in the 5G NR system, it is difficult to allocate many bits for specific information. In particular, when the number of TBs is two or the number of CCs is large, it is known that the MCS information has the poorest correlation or commonality between TBs or CCs compared to other PDCCH DCI fields. Therefore, it is necessary to transmit MCS information for many CCs with a relatively small amount of information by reducing or optimizing the number of bits representing the MCS information according to the situation. For this reason, the MCS information can be effectively transmitted through various options according to various embodiments of the present disclosure as described above. In addition, the above-described embodiments are useful for increasing the usability of scheduling using MC-DCI.

[0280] The above-mentioned proposed methods may be implemented independently, or may be implemented in a form of a combination (or merging) of some of the proposed methods. Rules can be defined so that the base station notifies the terminal of the application information (or the information on the rules of the proposed methods) via a predefined signal (e.g., a physical layer signal or a higher layer signal) of the proposed methods.

[0281] The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential features described in the present disclosure. Therefore, the above detailed description should not be interpreted as limiting in all respects, but should be considered as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalence of the present disclosure are included in the scope of the present disclosure. In addition, the claims that are not explicitly cited in the claims may be combined to form an embodiment, or may be included as a new claim by amendment after filing. [Industrial Applicability]

[0282] The embodiments of the present disclosure may be applied to various wireless access systems, such as 3GPP (3rd Generation Partnership Project) and 3GPP2 systems.

[0283] The embodiments of the present disclosure can be applied not only to the various wireless access systems but also to any technical field to which the various wireless access systems are applied. Furthermore, the proposed method can be applied to mmWave and THz communication systems using ultra-high frequency bands.

[0284] Additionally, embodiments of the present disclosure may be applied to a variety of applications, such as free-running vehicles and drones.

Claims

1. A method for operating a user equipment (UE) in a wireless communication system, comprising: performing a connection procedure with a base station; performing a connection establishment procedure for a primary cell with the base station; performing a connection establishment procedure for at least one secondary cell with the base station; receiving downlink control information (DCI) from the base station; receiving data using resources indicated by the DCI; The method, wherein the DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

2. The method of claim 1 , wherein the DCI includes information indicating at least one cell among the plurality of cells that is not actually scheduled.

3. 3. The method of claim 2, wherein the information indicating at least one cell that is not actually scheduled includes scrambling the DCI using a radio network temporary identifier (RNTI) for an alternative MCS table in a situation where a cell to which an RNTI for the alternative MCS table is not assigned is included.

4. The method of claim 1 , wherein the DCI includes an MCS value that is commonly applied to the multiple cells.

5. The method of claim 4, wherein the commonly applied MCS value is determined based on an MCS table that includes a portion of an index included in a full MCS table used for single carrier scheduling.

6. 2. The method of claim 1, further comprising transmitting information related to an MCS table used to determine the commonly applied MCS value via DCI, media access control (MAC) control element (CE) or radio resource control (RRC) signaling.

7. The method of claim 1 , wherein the DCI includes an MCS value for a reference cell among the plurality of cells and at least one delta value for at least one remaining cell.

8. the DCI includes a delta value for each of the plurality of cells; The method of claim 1 , wherein each of the delta values ​​indicates a difference between a reference MCS value and an MCS value for each of the plurality of cells.

9. The method of claim 8 , wherein the reference MCS value comprises an average of MCS values ​​of the multiple cells.

10. the MCS information includes an MCS value for each of the plurality of cells; The method according to claim 1 , wherein each of the MCS values ​​is commonly applied to a transport block (TB) included in the cell.

11. the MCS information includes a reference MCS value and at least one delta value for each of the plurality of cells; The reference MCS value is applied to any one of TBs included in the cell; The method of claim 1 , wherein the at least one delta value indicates an index difference between an MCS value to be applied to at least one remaining TB included in the cell and the reference MCS value.

12. 1. A method of operating a base station in a wireless communication system, comprising: A step of performing a connection procedure with a UE (user equipment); performing a connection establishment procedure for a primary cell of the UE; performing a connection establishment procedure for at least one secondary cell of the UE; sending downlink control information (DCI) to the UE; transmitting data using resources indicated by the DCI; The method, wherein the DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

13. The method of claim 12 , wherein the DCI includes information indicating at least one cell that is not actually scheduled among the primary cell and the at least one secondary cell.

14. 14. The method of claim 13, wherein the information indicating at least one cell that is not actually scheduled includes scrambling the DCI using a radio network temporary identifier (RNTI) for an alternative MCS table in a situation where a cell to which an RNTI for the alternative MCS table is not assigned is included.

15. The method of claim 12 , wherein the DCI includes an MCS value that is commonly applied to the multiple cells.

16. The method of claim 12, wherein the DCI includes an MCS value for a reference cell among the plurality of cells and at least one delta value for at least one remaining cell.

17. In a UE (user equipment) in a wireless communication system, A transceiver; a processor connected to the transceiver, The processor, Perform the connection procedure with the base station, performing a connection establishment procedure for a primary cell with the base station; performing a connection establishment procedure for at least one secondary cell with the base station; Receive downlink control information (DCI) from the base station; Controlling to receive data using resources indicated by the DCI; The DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

18. In a base station in a wireless communication system, A transceiver; a processor connected to the transceiver, The processor, Perform a connection procedure with UE (user equipment), performing a connection establishment procedure for a primary cell of the UE; performing a connection establishment procedure for at least one secondary cell of the UE; Sending downlink control information (DCI) to the UE; Controlling data transmission using resources indicated by the DCI; The DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

19. In a communication device, At least one processor; at least one computer memory coupled to the at least one processor and storing instructions that direct operations to be executed by the at least one processor; The operation includes: performing a connection procedure with a base station; performing a connection establishment procedure for a primary cell with the base station; performing a connection establishment procedure for at least one secondary cell with the base station; receiving downlink control information (DCI) from the base station; receiving data using resources indicated by the DCI; The DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

20. A non-transitory computer-readable medium storing at least one instruction, The at least one instruction executable by a processor, The at least one command may be provided to the device: Perform the connection procedure with the base station, performing a connection establishment procedure for a primary cell with the base station; performing a connection establishment procedure for at least one secondary cell with the base station; Receive downlink control information (DCI) from the base station; Instructing the receiving device to receive data using resources indicated by the DCI; The DCI includes information indicating modulation and coding scheme (MCS) information to be applied to a plurality of cells including the primary cell and the at least one secondary cell.

Images