A method and apparatus for multicasting and broadcasting in communication system

Abstract

The present disclosure relates to a 5G (5th generation) or pre-5G communication system for supporting higher data transmission rates than 4G (4th generation) communication systems such as LTE (Long Term Evolution). A method performed by a terminal in a communication system according to the present disclosure comprises: receiving configuration information for a group common resource from a base station; receiving downlink control information (DCI) from the base station based on the configuration information; checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling a CRC (cyclic redundancy check) attached to the DCI; and, if the group common RNTI is used, determining a code rate and a modulation order based on information related to a group common MCS (modulation and coding scheme).

Description

Technology Field

[0001] The present disclosure relates to a mobile communication system, and more specifically, to a method for transmitting data to a plurality of terminals. Background Technology

[0002] Efforts are being made to develop improved 5G or pre-5G communication systems to meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems. For this reason, 5G or pre-5G communication systems are referred to as systems beyond the 4G network or systems following the LTE (long term evolution) system. To achieve high data transmission rates, the implementation of 5G communication systems in the mmWave band (e.g., the 60 GHz band) is being considered. To mitigate path loss and increase transmission distance in the mmWave band, technologies such as beamforming, massive MIMO, full Dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large-scale antennas are being discussed for 5G communication systems. In addition, to improve the network of the system, the development of technologies such as advanced small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network, Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation is taking place in 5G communication systems.In addition, advanced coding modulation (ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), as well as advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (non-orthogonal multiple access), and SCMA (sparse code multiple access), are being developed in 5G systems.

[0003] Meanwhile, the Internet is evolving from a human-centric network where humans generate and consume information into an IoT (Internet of Things) network that processes information by exchanging it among distributed components, such as objects. IoE (Internet of Everything) technology, which combines IoT with Big Data processing technologies through connections with cloud servers, is also emerging. To implement IoT, technological elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required; consequently, technologies such as sensor networks, Machine-to-Machine (M2M) communication, and Machine-Type Communication (MTC) are currently being researched to facilitate the connection of objects. In an IoT environment, intelligent IT services that create new value for human life by collecting and analyzing data generated from connected objects can be provided. Through the convergence and integration of existing IT technologies with various industries, IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart home appliances, and advanced medical services.

[0004] Accordingly, various attempts are being made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, Machine to Machine (M2M), and Machine Type Communication (MTC) are being implemented using 5G communication techniques such as beamforming, MIMO, and array antennas. The application of cloud RAN as a big data processing technology, as previously described, can also be considered an example of the convergence of 5G and IoT technologies. The problem to be solved

[0005] The present disclosure provides a method and apparatus for configuring the transmission and reception of a group common PDSCH (physical downlink shared channel) and a unicast PDSCH in a communication system.

[0006] The present disclosure provides a method and apparatus for processing the transmission and reception of a group common PDSCH retransmission PDSCH in a communication system. means of solving the problem

[0007] According to various embodiments of the present disclosure, a method performed by a terminal in a communication system comprises: receiving configuration information for a group common resource from a base station; receiving downlink control information (DCI) from the base station based on the configuration information; checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling a CRC (cyclic redundancy check) attached to the DCI; and, if the group common RNTI is used, determining a code rate and a modulation order based on information related to a group common MCS (modulation and coding scheme).

[0008] Additionally, according to various embodiments of the present disclosure, a method performed by a base station in a communication system comprises: transmitting configuration information for a group common resource to a terminal; transmitting downlink control information (DCI) to the terminal based on the configuration information; and transmitting data based on the DCI, wherein when a group common RNTI (radio network temporary identifier) ​​is used for scrambling a CRC (cyclic redundancy check) attached to the DCI, the modulation and coding scheme (MCS) index included in the DCI is determined based on information related to the group common MCS (modulation and coding scheme).

[0009] In addition, according to various embodiments of the present disclosure, a terminal in a communication system comprises: a transceiver; and a control unit connected to the transceiver, receiving configuration information for a group common resource from a base station, receiving downlink control information (DCI) from the base station based on the configuration information, checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling of a CRC (cyclic redundancy check) attached to the DCI, and if the group common RNTI is used, determining a code rate and a modulation order based on information related to a group common MCS (modulation and coding scheme).

[0010] In addition, according to various embodiments of the present disclosure, a base station in a communication system comprises: a transceiver; and a control unit connected to the transceiver, which transmits configuration information for a group common resource to a terminal, transmits downlink control information (DCI) to the terminal based on the configuration information, and transmits data based on the DCI, wherein when a group common RNTI (radio network temporary identifier) ​​is used for scrambling of a CRC (cyclic redundancy check) attached to the DCI, the modulation and coding scheme (MCS) index included in the DCI is determined based on information related to the group common MCS (modulation and coding scheme). Effects of the invention

[0011] According to the present disclosure, when data is transmitted to a plurality of terminals in a communication system through a common PDSCH and a unicast PDSCH, more efficient data transmission and reception can be performed by providing a method for configuring the PDSCHs.

[0012] According to the present disclosure, by providing a method for processing the transmission and reception of a retransmission PDSCH of a group common PDSCH, a terminal and a base station can communicate smoothly. Brief explanation of the drawing

[0013] FIG. 1 is a drawing illustrating the structure of a next-generation mobile communication system according to one embodiment of the present disclosure. FIG. 2 is a diagram illustrating the wireless protocol structure of a next-generation mobile communication system according to one embodiment of the present disclosure. FIG. 3 is a diagram illustrating the basic structure of the time-frequency domain, which is a wireless resource domain in which data or a control channel is transmitted in a 5G communication system according to one embodiment of the present disclosure. FIG. 4 is a drawing illustrating an example of a slot structure considered in a 5G system according to one embodiment of the present disclosure. FIG. 5 is a diagram illustrating an example of a setting for a bandwidth portion in a 5G communication system according to one embodiment of the present disclosure. FIG. 6 is a drawing for explaining carrier aggregation (CA) according to one embodiment of the present disclosure. FIG. 7 is a diagram illustrating an example of a cross-carrier scheduling method according to one embodiment of the present disclosure. FIG. 8 is a diagram illustrating an example of setting a control resource set (CORESET) of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure. FIG. 9 is a diagram illustrating an example of processing a physical downlink shared channel in a wireless communication system according to one embodiment of the present disclosure. FIG. 10 is a diagram illustrating an example of a method for obtaining the size of a transport block in a wireless communication system according to one embodiment of the present disclosure. FIG. 11 is a diagram illustrating the mcs (modulation and coding scheme)-Table determination operation of a terminal according to one embodiment of the present disclosure. FIG. 12 is a diagram illustrating the DCI generation operation of a base station according to one embodiment of the present disclosure. FIG. 13 is a drawing illustrating an example of a downlink data channel of a terminal according to one embodiment of the present disclosure. FIG. 14 is a drawing illustrating an example of a method for obtaining the size of a transport block of a terminal according to one embodiment of the present disclosure. FIG. 15 is a drawing illustrating an example of a downlink data channel of a terminal according to one embodiment of the present disclosure. FIG. 16 is a drawing illustrating the structure of a terminal according to one embodiment of the present disclosure. FIG. 17 is a drawing illustrating the structure of a base station according to one embodiment of the present disclosure. Specific details for implementing the invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0015] In describing the embodiments, technical details that are well known in the technical field to which the present invention belongs and are not directly related to the present invention are omitted. This is intended to convey the essence of the present invention more clearly without obscuring it by omitting unnecessary explanations.

[0016] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the size of each component does not entirely reflect its actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference number.

[0017] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. The embodiments of the present disclosure are provided merely to make the disclosure complete and to fully inform those skilled in the art of the scope of the invention, and the present disclosure is defined only by the scope of the claims. Throughout the specification, like reference numerals refer to like components.

[0018] At this point, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory that can be directed toward the computer or other programmable data processing equipment to implement the function in a specific way, the instructions stored in computer-available or computer-readable memory can also produce a manufactured item containing means of instruction to perform the function described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that execute a computer or other programmable data processing equipment by performing a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer may also provide steps for executing the functions described in the flowchart block(s).

[0019] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specific logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For instance, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may be executed in reverse order depending on the corresponding function.

[0020] In this embodiment, the term "part" as used refers to a software or hardware component such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit), and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium or may be configured to run one or more processors. Accordingly, according to some embodiments, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." In addition, the components and 'parts' may be implemented to utilize one or more CPUs within the device or secure multimedia card. Also, according to some embodiments, the 'parts' may include one or more processors.

[0021] The operating principle of the present invention will be described in detail below with reference to the attached drawings. In describing the present invention below, if it is determined that a detailed description of related known functions or configurations may unnecessarily obscure the essence of the present invention, such detailed description will be omitted. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intentions or conventions of the user or operator. Therefore, such definitions should be based on the content throughout this specification. Hereinafter, a base station is an entity that performs resource allocation for terminals and may be at least one of a gNode B, eNode B, Node B, BS (Base Station), wireless access unit, base station controller, or a node on a network. A terminal may include a UE (User Equipment), MS (Mobile Station), cellular phone, smartphone, computer, or a multimedia system capable of performing communication functions. Of course, it is not limited to the above examples. Hereinafter, the present disclosure describes a technology for a terminal to receive broadcast information from a base station in a wireless communication system. The present disclosure is 4G (4 th 5G (5 generation) to support higher data transmission rates after the system th This disclosure relates to a communication technique and a system that fuses a communication system (generation) with IoT (Internet of Things) technology. The present disclosure can be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail, security and safety-related services, etc.) based on 5G communication technology and IoT-related technology.

[0022] Terms used in the following description to refer to broadcast information, control information, communication coverage, state changes (e.g., events), network entities, messages, and device components are examples provided for the convenience of explanation. Accordingly, the present invention is not limited to the terms described below, and other terms having equivalent technical meanings may be used.

[0023] For the convenience of the following description, some terms and names defined in the 3GPP LTE (3rd generation partnership project long term evolution) standard or 3GPP NR (new radio or new radio access technology) may be used. However, the present invention is not limited by the above terms and names and can be applied in the same way to systems conforming to other standards.

[0024] FIG. 1 is a drawing illustrating the structure of a next-generation mobile communication system according to one embodiment of the present disclosure.

[0025] Referring to FIG. 1, the wireless access network of a next-generation mobile communication system (hereinafter NR or 5G) may be composed of a next-generation base station (new radio node B, hereinafter NR gNB or NR base station) (110) and a next-generation wireless core network (new radio core network, NR CN) (105). A next-generation wireless user terminal (new radio user equipment, NR UE or terminal) (115) may connect to an external network through the NR gNB (110) and the NR CN (105).

[0026] In FIG. 1, the NR gNB (110) can correspond to the eNB (evolved node B) of the existing LTE system. The NR gNB is connected to the NR UE (115) via a wireless channel and can provide a service that is more advanced than that of the existing node B. In the next-generation mobile communication system, all user traffic can be serviced through a shared channel. Therefore, a device is required to collect state information such as the buffer status, available transmission power status, and channel status of the UEs and perform scheduling, and the NR gNB (110) can handle this. A single NR gNB can control multiple cells. In the next-generation mobile communication system, a bandwidth greater than the current maximum bandwidth can be applied to achieve ultra-high-speed data transmission compared to current LTE. Additionally, beamforming technology can be incorporated by using orthogonal frequency division multiplexing (OFDM) as the wireless access technology. In addition, an adaptive modulation & doding (hereinafter referred to as AMC) scheme that determines the modulation scheme and channel coding rate according to the channel conditions of the terminal may be applied.

[0027] The NR CN (105) can perform functions such as mobility support, bearer configuration, and QoS configuration. The NR CN is a device responsible for various control functions as well as mobility management functions for terminals, and can be connected to multiple base stations. In addition, the next-generation mobile communication system can be interoperable with existing LTE systems, and the NR CN can be connected to the MME (125) via a network interface. The MME can be connected to the existing base station eNB (130).

[0028] FIG. 2 is a diagram illustrating the wireless protocol structure of a next-generation mobile communication system according to one embodiment of the present disclosure.

[0029] Referring to FIG. 2, the wireless protocol of the next-generation mobile communication system consists of an NR service data adaptation protocol (SDAP) (201, 245), an NR PDCP (205, 240), an NR RLC (210, 235), an NR MAC (215, 230), and an NR PHY (220, 225) at the terminal and the NR base station, respectively.

[0030] The main functions of NR SDAP (201, 245) may include some of the following functions.

[0031] - User data transfer function (transfer of user plane data)

[0032] - Mapping function between a QoS flow and a DRB for both DL and UL for uplink and downlink

[0033] - Marking QoS flow ID in both DL and UL packets for uplink and downlink

[0034] - Function to map reflective QoS flow to data bearers for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0035] For SDAP layer devices, the terminal may receive a radio resource control (RRC) message indicating whether to use the SDAP layer device header or the SDAP layer device functions for each PDCP layer device, for each bearer, or for each logical channel. If the SDAP header is configured, the terminal may be instructed to update or reset the mapping information for the uplink and downlink QoS flows and data bearers using the 1-bit NAS reflective QoS indicator and the 1-bit AS reflective QoS indicator of the SDAP header. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used for data processing priorities, scheduling information, etc., to support seamless service.

[0036] The main functions of NR PDCP (205, 240) may include some of the following functions.

[0037] - Header compression and decompression features (ROHC only)

[0038] - User data transfer function (Transfer of user data)

[0039] - Sequential delivery function (In-sequence delivery of upper layer PDUs)

[0040] - Out-of-sequence delivery of upper layer PDUs

[0041] - Reordering function (PDCP PDU reordering for reception)

[0042] - Duplicate detection function (Duplicate detection of lower layer SDUs)

[0043] - Retransmission of PDCP SDUs

[0044] - Encryption and decryption functions (Ciphering and deciphering)

[0045] - Timer-based SDU discard in uplink.

[0046] In the above description, the reordering function of the NR PDCP device may refer to a function that reorders PDCP PDUs received from a lower layer in order based on the PDCP SN (sequence number). The reordering function of the NR PDCP device may include a function to transmit data to an upper layer in the reordered order, a function to transmit immediately without considering the order, a function to record lost PDCP PDUs by reordering, a function to report the status of lost PDCP PDUs to the transmitting side, and a function to request retransmission of lost PDCP PDUs.

[0047] The main functions of NR RLC (210, 235) may include some of the following functions.

[0048] - Data transfer function (Transfer of upper layer PDUs)

[0049] - Sequential delivery function (In-sequence delivery of upper layer PDUs)

[0050] - Out-of-sequence delivery of upper layer PDUs

[0051] - ARQ function (Error Correction through ARQ)

[0052] - Concatenation, segmentation, and reassembly functions of RLC SDUs

[0053] - Re-segmentation function (Re-segmentation of RLC data PDUs)

[0054] - Reordering function (Reordering of RLC data PDUs)

[0055] - Duplicate detection

[0056] - Error detection function (Protocol error detection)

[0057] - RLC SDU discard function

[0058] RLC re-establishment function

[0059] In the above description, the in-sequence delivery function of the NR RLC device may refer to the function of delivering RLC SDUs received from a lower layer to an upper layer in sequence. In the case where a single RLC SDU is received divided into multiple RLC SDUs, the in-sequence delivery function of the NR RLC device may include the function of reassembling and delivering them.

[0060] The in-sequence delivery function of the NR RLC device may include a function to rearrange received RLC PDUs based on an RLC SN (sequence number) or PDCP SN (sequence number), a function to record lost RLC PDUs by rearranging the order, a function to report the status of lost RLC PDUs to the transmitting side, and a function to request retransmission of lost RLC PDUs.

[0061] The in-sequence delivery function of the NR RLC (210, 235) device may include a function to deliver only the RLC SDUs prior to the lost RLC SDU in order to the upper layer if there is a lost RLC SDU. Additionally, the in-sequence delivery function of the NR RLC device may include a function to deliver all RLC SDUs received before the timer started in order to the upper layer if a predetermined timer has expired even if there is a lost RLC SDU. Additionally, the in-sequence delivery function of the NR RLC device may include a function to deliver all RLC SDUs received up to the present in order to the upper layer if a predetermined timer has expired even if there is a lost RLC SDU.

[0062] The NR RLC (210, 235) device can process the RLC PDUs in the order they are received, regardless of the sequence number (Out of sequence delivery), and deliver them to the NR PDCP (205, 240) device.

[0063] When the NR RLC (210, 235) device receives a segment, it may receive segments that are stored in a buffer or will be received later, reconstruct them into a complete RLC PDU, and then transmit it to the NR PDCP device.

[0064] The NR RLC layer may not include a concatenation function, and the function may be performed by the NR MAC layer or replaced by the multiplexing function of the NR MAC layer.

[0065] In the above description, the out-of-sequence delivery function of the NR RLC device may refer to a function of delivering RLC SDUs received from a lower layer directly to an upper layer regardless of order. The out-of-sequence delivery function of the NR RLC device may include a function of reassembling and delivering RLC SDUs when a single RLC SDU is received divided into multiple RLC SDUs. The out-of-sequence delivery function of the NR RLC device may include a function of storing the RLC SN or PDCP SN of the received RLC PDUs, sorting the order, and recording the lost RLC PDUs.

[0066] The NR MAC (215, 230) can be connected to multiple NR RLC layer devices configured in a terminal, and the main functions of the NR MAC may include some of the following functions.

[0067] - Mapping function (Mapping between logical channels and transport channels)

[0068] - Multiplexing and demultiplexing functions (Multiplexing / demultiplexing of MAC SDUs)

[0069] - Scheduling information reporting function

[0070] - HARQ function (Error correction through HARQ (hybrid automatic repeat request))

[0071] - Priority handling between logical channels of one UE

[0072] - Priority handling between UEs by means of dynamic scheduling

[0073] - MBMS service identification function

[0074] - Transport format selection function

[0075] - Padding

[0076] The NR PHY layer (220, 225) can perform the operation of channel coding and modulating upper layer data, creating OFDM symbols and transmitting them to the wireless channel, or demodulating OFDM symbols received through the wireless channel and channel decoding them to transmit them to the upper layer.

[0077] The frame structure of the 5G system will be explained in more detail below with reference to the drawings.

[0078] Figure 3 is a diagram illustrating the basic structure of the time-frequency domain, which is a wireless resource domain where data or control channels are transmitted in a 5G system.

[0079] The horizontal axis of FIG. 3 represents the time domain, and the vertical axis represents the frequency domain. In the time and frequency domains, the basic unit of a resource is a resource element (RE) (301), which can be defined as one OFDM (orthogonal frequency division multiplexing) symbol (302) on the time axis and one subcarrier (303) on the frequency axis. In the frequency domain (For example, 12) consecutive REs can form a resource block (RB) (304).

[0080] Figure 4 is a diagram illustrating an example of a slot structure considered in a 5G system.

[0081] FIG. 4 illustrates an example of a frame (400), subframe (401), and slot (402) structure. One frame (400) can be defined as 10ms. One subframe (401) can be defined as 1ms, and thus one frame (400) can be composed of a total of 10 subframes (401). One slot (402, 403) can be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( )=14). One subframe (401) may be composed of one or more slots (402, 403), and the number of slots (402, 403) per one subframe (401) may vary depending on the setting value μ (404, 405) for the subcarrier spacing. In one example of FIG. 4, cases where μ=0 (404) and μ=1 (405) are set as the subcarrier spacing value are illustrated. When μ=0 (404), one subframe (401) may be composed of one slot (402), and when μ=1 (405), one subframe (401) may be composed of two slots (403). That is, the number of slots per one subframe ( ) may vary, and accordingly, the number of slots per frame ( ) may vary. Depending on each subcarrier spacing setting μ and It can be defined by Table 1 below.

[0082] [Table 1]

[0083]

[0084] Next, the Bandwidth Part (BWP) setting in a 5G communication system will be explained in detail with reference to Fig. 5.

[0085] Figure 5 is a diagram illustrating an example of a configuration for a bandwidth portion in a 5G communication system.

[0086] FIG. 5 illustrates an example in which the terminal bandwidth (UE bandwidth) (500) is configured into two bandwidth portions, namely Bandwidth portion #1 (BWP#1) (501) and Bandwidth portion #2 (BWP#2) (502). The base station may configure one or more bandwidth portions for the terminal, and for each bandwidth portion, it may configure information such as that shown in Table 2 below, for example. The BWP below may be referred to as BWP configuration information.

[0087] [Table 2]

[0088]

[0089] Of course, the above examples are not limited, and various parameters related to bandwidth portions may be configured for the terminal in addition to the above configuration information. The above information may be transmitted from the base station to the terminal via upper-layer signaling, for example, RRC signaling. At least one of the configured bandwidth portions may be activated. Whether a configured bandwidth portion is activated may be transmitted semi-statically from the base station to the terminal via RRC signaling or dynamically via DCI (downlink control information).

[0090] According to some embodiments, prior to the RRC connection, the terminal may receive an initial bandwidth portion (initial BWP) for initial connection from the base station via a master information block (MIB). More specifically, during the initial connection phase, the terminal may receive configuration information for a core set and a search space via the MIB, through which a PDCCH can be transmitted for receiving system information required for initial connection (remaining system information; which may correspond to RMSI or system Information block 1; SIB1). The core set and search space configured via the MIB may each be considered as identity (ID) 0. The base station may notify the terminal via the MIB of configuration information, such as frequency allocation information, time allocation information, and numerology, for core set #0. Additionally, the base station may notify the terminal via the MIB of configuration information regarding the monitoring period and occasion for core set #0, i.e., configuration information for search space #0. The terminal may consider the frequency range set by the control resource set #0 obtained from the MIB as the initial bandwidth portion for initial access. In this case, the identifier (ID) of the initial bandwidth portion may be considered as 0.

[0091] The settings for the bandwidth portion supported by the above 5G can be used for various purposes.

[0092] According to some embodiments, if the bandwidth supported by the terminal is smaller than the system bandwidth, this can be supported through the bandwidth portion setting. For example, by the base station setting the frequency position of the bandwidth portion (setting information 2) to the terminal, the terminal can transmit and receive data at a specific frequency position within the system bandwidth.

[0093] In addition, according to some embodiments, a base station may set multiple bandwidth portions for a terminal for the purpose of supporting different numerologies. For example, to support data transmission and reception using both a 15 kHz subcarrier interval and a 30 kHz subcarrier interval for a terminal, two bandwidth portions may be set to subcarrier intervals of 15 kHz and 30 kHz, respectively. Different bandwidth portions may be frequency division multiplexed, and when data transmission and reception is to be performed with a specific subcarrier interval, the bandwidth portion set to that subcarrier interval may be activated.

[0094] In addition, according to some embodiments, a base station may set a bandwidth portion having different bandwidth sizes for the purpose of reducing the power consumption of the terminal. For example, if the terminal supports a very large bandwidth, such as 100 MHz, and always transmits and receives data using that bandwidth, very large power consumption may occur. In particular, in a situation where there is no traffic, performing monitoring of an unnecessary downlink control channel using a large bandwidth of 100 MHz may be very inefficient in terms of power consumption. To reduce the power consumption of the terminal, the base station may set a bandwidth portion of a relatively small bandwidth, such as 20 MHz, for the terminal. In a situation where there is no traffic, the terminal can perform monitoring operations in the 20 MHz bandwidth portion, and when data is generated, it can transmit and receive data using the 100 MHz bandwidth portion according to the instructions of the base station.

[0095] Regarding the method of configuring the bandwidth part, terminals prior to RRC connection can receive configuration information for the initial bandwidth part via the MIB during the initial connection phase. More specifically, the terminal can receive a CORESET for a downlink control channel through which a DCI scheduling SIBs can be transmitted from the MIB of the PBCH (physical broadcast channel). The bandwidth of the CORESET configured by the MIB can be considered as the initial bandwidth part, and through the configured initial bandwidth part, the terminal can receive the PDSCH through which SIBs are transmitted. In addition to receiving SIBs, the initial bandwidth part may also be utilized for other system information (OSI), paging, and random access.

[0096] FIG. 6 is a drawing for explaining a carrier aggregation (CA) according to one embodiment of the present disclosure.

[0097] Referring to Fig. 6, when CA is configured (600), PCell (primary cell) and SCell (secondary cell) can be configured in the terminal.

[0098] PCell is included in the PCC (primary component carrier) and can provide RRC connection establishment / re-establishment, measurement, mobility procedures, random access procedures and selection, system information acquisition, initial random access, security key change and non-access stratum (NAS) functions.

[0099] Since the terminal performs system information monitoring through the PCell, the PCell is not deactivated, and in the UL, the PCC is carried via the PUCCH (physical uplink control channel) for the transmission of control information. Additionally, only one RRC can be connected between the terminal and the PCell, and PDCCH / PDSCH / PUSCH (physical uplink shared channel) / PUCCH transmission is possible. Furthermore, in a secondary cell group, the PSCell (spcell of a secondary cell group) can be configured and operated as the PCell. The operations for the PCell described below can also be performed by the PSCell.

[0100] Up to a total of 31 SCells can be added, and SCells can be configured via RRC messages (e.g., dedicated signaling) when additional radio resources are required. RRC messages may include the physical cell ID for each cell and the DL carrier frequency (absolute radio frequency channel number: ARFCN). PDCCH / PDSCH / PUSCH transmission is possible through SCells. Dynamic activation and deactivation procedures for SCells are supported via the MAC layer to conserve the UE's battery.

[0101] Cross-carrier scheduling may mean assigning at least one of all L1 control channels or L2 control channels (e.g., PDCCH) for at least one other component carrier (CC) to a single CC. A carrier indicator field (CIF) may be used to transmit data information from another CC through the PDCCH of one CC.

[0102] Resources for data transmission of said CC (PDSCH, PUSCH) or resources for data transmission of another CC (PDSCH, PUSCH) can be allocated through control information transmitted through the PDCCH of one CC.

[0103] With the application of cross-carrier scheduling, n-bit CIF is added to the DCI format, and the bit size may vary depending on the upper layer settings or the DCI format, and the position of the CIF within the DCI format may be fixed.

[0104] FIG. 7 is a diagram illustrating an example of a cross-carrier scheduling method according to one embodiment of the present disclosure.

[0105] Referring to 710 in Fig. 7, PDSCH or PUSCH for two CCs can be scheduled through PDCCH (701) of one CC.

[0106] In addition, referring to 720 in Fig. 7, when a total of 4 CCs are set, the PDSCH or PUSCH of each CC can be scheduled using the PDCCH (721, 723) of two CCs.

[0107] Each CC can be mapped to a CI (carrier indicator) value for CIF application, and this can be transmitted from the base station to the terminal via a dedicated RRC signal with UE-specific settings.

[0108] Each PDSCH / PUSCH CC can be scheduled from a single DL CC. Therefore, for each PDSCH / PUSCH CC, the UE only needs to monitor the PDCCH from the said DL CC. The terminal can obtain PUSCH scheduling information from the linked UL carrier by monitoring the PDCCH from the said DL CC. The terminal can obtain PDSCH scheduling information from the linked DL carrier by monitoring the PDCCH from the said DL CC.

[0109] FIG. 8 is a diagram illustrating an example of setting a control area (CORESET) of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0110] Referring to FIG. 8, FIG. 8 illustrates an example in which two control areas (control area #1 (CORESET #1) (801), control area #2 (CORESET #2) (802)) are set within a single slot (820) in the frequency axis and within a terminal bandwidth portion (810) in the time axis. The control areas (801, 802) can be set in a specific frequency resource (803) within the entire terminal bandwidth portion (810) in the frequency axis. The control areas (801, 802) can be set with one or more OFDM symbols in the time axis, which can be defined as the control resource set duration (804). In the example of FIG. 8, control area #1 (801) is set with a control resource set duration of two symbols, and control area #2 (802) is set with a control resource set duration of one symbol.

[0111] The control domain in 5G described above can be configured by a base station to a terminal through upper-layer signaling (e.g., system information, MIB, RRC signaling). Configuring a control domain to a terminal means providing the terminal with information such as a control domain identifier, the frequency location of the control domain, and the symbol length of the control domain. For example, the information in Table 3 may be included.

[0112] [Table 3]

[0113]

[0114]

[0115] The number of CCEs required to transmit a PDCCH can be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and different numbers of CCEs can be used to implement link adaptation for the downlink control channel. For example, when AL=L, one downlink control channel can be transmitted through L CCEs. The terminal must detect the signal (blind decoding) without knowing information about the downlink control channel, and a search space representing a set of CCEs is defined for blind decoding. The search space is a set of downlink control channel candidates consisting of CCEs that the terminal must attempt to decode at a given aggregation level; since there are various aggregation levels that form a group of 1, 2, 4, 8, or 16 CCEs, the terminal may have multiple search spaces. A search space set can be defined as a set of search spaces at all configured aggregation levels.

[0116] Search spaces can be classified into common search spaces and UE-specific search spaces. A certain group of terminals or all terminals may examine the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling or paging messages regarding system information. For example, PDSCH scheduling allocation information for the transmission of SIBs containing cell operator information can be received by examining the common search space of the PDCCH. In the case of the common search space, since a certain group of terminals or all terminals must receive the PDCCH, it can be defined as a pre-arranged set of CCEs. Scheduling allocation information for a UE-specific PDSCH or PUSCH can be received by examining the UE-specific search space of the PDCCH. The UE-specific search space can be defined specifically as a function of the terminal's identity and various system parameters.

[0117] In 5G, parameters for the search space for a PDCCH can be configured from the base station to the terminal via upper layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station may configure the terminal the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the occasion for monitoring in slot-symbol units for the search space, the search space type (common search space or terminal-specific search space), the combination of the DCI format and RNTI (radio network temporary identifier) ​​to be monitored in the search space, and the control resource set index to be monitored in the search space. For example, parameters for the search space for a PDCCH may include at least some of the information such as that shown in Table 4 below.

[0118] [Table 4]

[0119]

[0120]

[0121]

[0122] A base station may set one or more sets of search spaces for a terminal. According to some embodiments, a base station may set search space set 1 and search space set 2 for a terminal. In search space set 1, the terminal may be configured to monitor DCI format A scrambled with X-RNTI in a common search space, and in search space set 2, the terminal may be configured to monitor DCI format B scrambled with Y-RNTI in a terminal-specific search space.

[0123] According to the configuration information, one or more sets of search spaces may exist in a common search space or a terminal-specific search space. For example, Search Space Set #1 and Search Space Set #2 may be configured as a common search space, and Search Space Set #3 and Search Space Set #4 may be configured as a terminal-specific search space.

[0124] In the common search space, the following combinations of DCI formats and RNTI can be monitored. Of course, they are not limited to the examples below.

[0125] DCI format 0_0 / 1_0 with CRC (cyclic redundancy check) scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

[0126] DCI format 2_0 with CRC scrambled by SFI-RNTI

[0127] DCI format 2_1 with CRC scrambled by INT-RNTI

[0128] DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0129] DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0131] In terminal-specific search spaces, the following combinations of DCI formats and RNTI can be monitored. Of course, they are not limited to the examples below.

[0132] DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0133] DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0135] The specified RNTIs may follow the definitions and uses below.

[0136] C-RNTI (Cell RNTI): Used for terminal-specific PDSCH scheduling

[0137] TC-RNTI (Temporary Cell RNTI): Used for terminal-specific PDSCH scheduling

[0138] CS-RNTI (Configured Scheduling RNTI): Used for semi-statically configured terminal-specific PDSCH scheduling.

[0139] RA-RNTI (Random Access RNTI): Used for PDSCH scheduling during the random access phase

[0140] P-RNTI (Paging RNTI): Used for PDSCH scheduling where paging is transmitted.

[0141] SI-RNTI (System Information RNTI): Used for PDSCH scheduling where system information is transmitted.

[0142] INT-RNTI (Interruption RNTI): Used to indicate whether PDSCH is pucturing.

[0143] TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to instruct power control commands to the PUSCH

[0144] TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to instruct power control commands to the PUCCH

[0145] TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used to instruct power regulation commands to the SRS

[0146] Control resource set in 5G p , search space set s at the lamination level L The search space of can be expressed as shown in Equation 1 below.

[0147] [Mathematical Formula 1]

[0148]

[0149]

[0150] The value may be 0 for the common search space.

[0151] In the case of a terminal-specific search space, the value may correspond to a value that changes according to the terminal's identity (C-RNTI or ID set by the base station for the terminal) and the time index.

[0152] Therefore, the terminal can monitor the PDCCH in a control area set from the base station and transmit and receive data based on the received control information.

[0153] In a 5G system, scheduling information for uplink data (or physical uplink data channel (PUSCH)) or downlink data (or physical downlink data channel (PDSCH)) can be transmitted from a base station to a terminal via DCI. The terminal can monitor the fallback DCI format and the non-fallback DCI format for PUSCH or PDSCH. The fallback DCI format may consist of fixed fields selected between the base station and the terminal, and the non-fallback DCI format may include configurable fields.

[0154] DCI can be transmitted via the PDCCH, a physical downlink control channel, after undergoing channel coding and modulation processes. A CRC is attached to the DCI message payload, and the CRC can be scrambled based on the RNTI corresponding to the terminal's identity. Different RNTIs may be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control commands, or random access responses. In other words, the RNTI is not explicitly transmitted but is included in the CRC calculation process. Upon receiving a DCI message transmitted over the PDCCH, the terminal checks the CRC using its assigned RNTI; if the CRC check result is correct, the terminal knows that the message has been transmitted to it.

[0155] For example, a DCI scheduling a PDSCH for system information (SI) can be scrambled to SI-RNTI. A DCI scheduling a PDSCH for a random access response (RAR) message can be scrambled to RA-RNTI. A DCI scheduling a PDSCH for a paging message can be scrambled to P-RNTI. A DCI notifying a slot format indicator (SFI) can be scrambled to SFI-RNTI. A DCI notifying a transmit power control (TPC) can be scrambled to TPC-RNTI. A DCI scheduling a terminal-specific PDSCH or PUSCH can be scrambled to C-RNTI (cell RNTI).

[0156] Meanwhile, NR can provide various forms of DCI formats as shown in Table 5 below to efficiently receive control information from the terminal.

[0157] DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1 Scheduling of PUSCH in one cell 0_2 Scheduling of PUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1 Scheduling of PDSCH in one cell 1_2 Scheduling of PDSCH in one cell 2_0 Notifying a group of UEs of the slot format 2_1 Notifying a group of UEs of the PRB(s) and OFDM symbol(s) where UE may assume no transmission is intended for the UE 2_2 Transmission of TPC commands for PUCCH and PUSCH 2_3 Transmission of a group of TPC commands for SRS transmissions by one or more UEs

[0158] For example, a base station may use DCI format 1_0, DCI format 1_1, or DCI format 1_2 to schedule PDSCH for a cell to a terminal. As another example, a base station may use DCI format 0_0, DCI format 0_1, or DCI format 0_2 to schedule PUSCH for a cell to a terminal.

[0159] When DCI format 1_0 is transmitted with a CRC scrambled by C-RNTI, CS-RNTI, MCS-C-RNTI, or new-RNTI, it may include, for example, at least information such as that in Table 6:

[0160] - Identifier for DCI formats(1 bit): Always set to 1 as the DCI format identifier - frequency domain resource assignment(N RBG bits or bits): Indicates frequency axis resource allocation, and when DCI format 1_0 is monitored in the UE-specific search space is the size of the active DL BWP, and in other cases is the size of the initial DL BWP. N RBG is the number of resource block groups. For detailed methods, refer to the frequency axis resource allocation above. - Time domain resource assignment (0~4 bits): Indicates the time axis resource allocation for PDSCH. - VRB-to-PRB mapping (1 bit): Indicates non-interleaved VRP-to-PRB mapping if 0, and interleaved VRP-to-PRB mapping if 1. - Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate used for PDSCH transmission. - New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission depending on whether it is toggled. - Redundancy version (2 bits): Indicates the redundancy version used for PDSCH transmission. - HARQ process number (4 bits): Indicates the HARQ process number used for PDSCH transmission. - Downlink assignment index (2 bits): DAI indicator. - TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator. - PUCCH resource indicator (3 bits): PUCCH resource indicator, representing the 8 resources configured in the upper layer. Indicates one of the following: - PDSCH-to-HARQ_feedback timing indicator(3 bits): HARQ feedback timing indicator, which indicates one of the 8 feedback timing offsets set to the upper layer.

[0161] When DCI format 1_1 is transmitted with a CRC scrambled by C-RNTI (cell radio network temporary identifier), CS-RNTI (configured scheduling RNTI), MCS-C-RNTI, or new-RNTI, it may include, for example, at least information such as that in Table 7.

[0162] - Identifier for DCI formats (1 bit): DCI format indicator, always set to 1 - Carrier indicator (0 or 3 bits): Indicates the CC (or cell) to which the PDSCH assigned by the corresponding DCI is transmitted. - Bandwidth part indicator (0, 1, or 2 bits): Indicates the BWP to which the PDSCH assigned by the corresponding DCI is transmitted. - Frequency domain resource assignment (payload determined according to the above frequency domain resource assignment): Indicates the frequency domain resource assignment, and is the size of the active DL BWP. For detailed methods, refer to the frequency axis resource allocation above. - Time domain resource assignment (0 ~ 4 bits): Indicates time axis resource allocation according to the above description. - VRB-to-PRB mapping (0 or 1 bit): If 0, indicates non-interleaved; if 1, indicates interleaved VRP-to-PRB mapping. It is a 0 bit if frequency axis resource allocation is set to resource allocation type 0 or if interleaved VRB-to-PRB mapping is not set by the upper layer. - PRB bundling size indicator (0 or 1 bit): It is a 0 bit if the upper layer parameter prb-BundlingType is not set or is set to 'static', and a 1 bit if set to 'dynamic'. - Rate matching indicator (0 or 1 or 2 bits): Indicates the rate matching pattern. - ZP CSI-RS trigger (0 or 1 or 2 bits): An indicator that triggers aperiodic ZP CSI-RS. - For transport block 1: - Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate used for PDSCH transmission. - New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission depending on whether it is toggled. - Redundancy version (2 bits): Indicates the redundancy version used for PDSCH transmission. - For transport block 2:- Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate used for PDSCH transmission.- New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission depending on whether it is toggled. - Redundancy version (2 bits): Indicates the redundancy version used for the PDSCH transmission. - HARQ process number (4 bits): Indicates the HARQ process number used for the PDSCH transmission. - Downlink assignment index (0 or 2 or 4 bits): DAI indicator. - TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator. - PUCCH resource indicator (3 bits): PUCCH resource indicator, indicating one of the 8 resources configured at the upper layer. - PDSCH-to-HARQ_feedback timing indicator (3 bits): HARQ feedback timing indicator, indicating one of the 8 feedback timing offsets configured at the upper layer. - Antenna port (4 or 5 or 6 bits): Indicates the DMRS port and CDM group without data. - Transmission configuration indication (0 or 3 bits): TCI indicator. - SRS request(2 or 3 bits): SRS transmission request indicator - CBG transmission information(0 or 2 or 4 or 6 or 8 bits): Indicator indicating whether code block groups within the assigned PDSCH are transmitted. 0 means that the corresponding CBG is not transmitted, and 1 means that it is transmitted.- CBG flushing out information (0 or 1 bit): An indicator showing whether previous CBGs are corrupted; 0 means they may be corrupted, and 1 means they are combinable for retransmission reception. - DMRS sequence initialization (0 or 1 bit): Indicator for selecting the DMRS scrambling ID.

[0163] When DCI format 1_2 is transmitted with a CRC scrambled by C-RNTI (cell radio network temporary identifier), CS-RNTI (configured scheduling RNTI), MCS-C-RNTI, or new-RNTI, it may include, for example, at least information such as that in Table 8.

[0164] - Identifier for DCI formats (1 bit): DCI format indicator, always set to 1 - Carrier indicator (0 or 1 or 2 or 3 bits): Indicates the CC (or cell) where the PDSCH assigned by the corresponding DCI is transmitted. - Bandwidth part indicator (0 or 1 or 2 bits): Indicates the BWP where the PDSCH assigned by the corresponding DCI is transmitted. - Frequency domain resource assignment (payload determined according to the above frequency domain resource assignment): Indicates the frequency domain resource assignment, and is the size of the active DL BWP. For detailed methods, refer to the frequency axis resource allocation above. - Time domain resource assignment (0 ~ 4 bits): Indicates time axis resource allocation according to the above description. - VRB-to-PRB mapping (0 or 1 bit): If 0, indicates non-interleaved; if 1, indicates interleaved VRP-to-PRB mapping. - 0 bit if the upper layer's vrb-ToPRB-InterleaverForDCI-Format1-2 configuration parameter is not set. - PRB bundling size indicator (0 or 1 bit): 0 bit if the upper layer parameter prb-BundlingTypeForDCI-Format1-2 is not set or is set to 'static', and 1 bit if set to 'dynamic'. - Rate matching indicator (0 or 1 or 2 bits): Indicates the rate matching pattern. - ZP CSI-RS trigger (0 or 1 or 2 bits): An indicator that triggers aperiodic ZP CSI-RS. - Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate used for PDSCH transmission. - New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission depending on whether it is toggled. - Redundancy version (0 or 1 or 2 bits): Indicates the redundancy version used for PDSCH transmission. HARQ process number(0 or 1 or 2 or 3 or 4 bits): Indicates the HARQ process number used for PDSCH transmission.- Downlink assignment index (0 or 1 or 2 or 4 bits): DAI indicator - TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator - PUCCH resource indicator (0 or 1 or 2 or 3 bits): PUCCH resource indicator, indicating one of the resources configured at the upper layer - PDSCH-to-HARQ_feedback timing indicator (0 or 1 or 2 or 3 bits): HARQ feedback timing indicator, indicating one of the feedback timing offsets configured at the upper layer - Antenna port (4 or 5 or 6 bits): Indicates DMRS port and CDM group without data - Transmission configuration indication (0 or 1 or 2 or 3 bits): TCI indicator - SRS request (0 or 1 or 2 or 3 bits): SRS transmission request indicator - DMRS sequence initialization (0 or 1 bit): DMRS scrambling ID selection indicator - Priority indicator (0 or 1 bit): Upper layer 0 bit if priorityIndicatorForDCI-Format1-2 parameter is not set, 1 bit if set.

[0165] The maximum number of different sizes of DCIs that a terminal can receive per slot in the cell is 4. The maximum number of different sizes of DCIs scrambled with C-RNTI that a terminal can receive per slot in the cell is 3.

[0166] The base station can set time-domain resource allocation information for the downlink data channel (PDSCH) and uplink data channel (PUSCH) for the terminal (e.g., information configured in the form of a table) through upper-layer signaling (e.g., RRC signaling). For PDSCH, the base station can set resource allocation information consisting of a maximum of maxNrofDL-Allocations = 16 entries (e.g., information configured in the form of a table), and for PUSCH, resource allocation information consisting of a maximum of maxNrofUL-Allocations = 16 entries (e.g., information configured in the form of a table). Time domain resource allocation information may include, for example, PDCCH-to-PDSCH slot timing (corresponding to a slot-unit time interval between the time when the PDCCH is received and the time when the PDSCH scheduled by the received PDCCH is transmitted, denoted as K0) or PDCCH-to-PUSCH slot timing (corresponding to a slot-unit time interval between the time when the PDCCH is received and the time when the PUSCH scheduled by the received PDCCH is transmitted, denoted as K2), information regarding the position and length of the starting symbol for which the PDSCH or PUSCH is scheduled within the slot, and the mapping type of the PDSCH or PUSCH. For example, information such as that shown in Table 9 or Table 10 below may be notified from the base station to the terminal.

[0167] [Table 9]

[0168]

[0169] [Table 10]

[0170]

[0171] The base station may notify the terminal of one of the entries in the table for the time domain resource allocation information via L1 signaling (e.g., DCI) (e.g., may indicate the time domain resource allocation field within the DCI). The terminal may obtain time domain resource allocation information for PDSCH or PUSCH based on the DCI received from the base station.

[0172] The following describes the frequency domain resource allocation method for data channels in a 5G communication system.

[0173] In 5G, two types, resource allocation type 0 and resource allocation type 1, are supported as methods for indicating frequency domain resource allocation information for downlink data channels (PDSCH) and uplink data channels (PUSCH).

[0174] In resource allocation type 0, RB allocation information may be notified from the base station to the terminal in the form of a bitmap for a resource block group (RBG). In this case, the RBG may be composed of a set of consecutive VRBs, and the size P of the RBG may be determined based on a value set as an upper layer parameter (rbg-Size) and the size value of the bandwidth part defined as in Table 11 below.

[0175] [Table 11] Nominal RGB size P

[0176]

[0177] The size Total number of RGBs in bandwidth part i ( ) can be defined as follows.

[0178] , where

[0179] the size of the first RBG is ,

[0180] the size of last RBG is if and P otherwise,

[0181] the size of all other RBGs is P.

[0182] Each bit of a bitmap of bit size can correspond to a respective RGB. The RGBs can be indexed in increasing order of frequency, starting from the lowest frequency position in the bandwidth part. Within the bandwidth part For the RBGs, from RBG#0 to RBG#( ) can be mapped from the MSB to the LSB of the RGB bitmap. If a specific bit value in the bitmap is 1, the terminal can determine that the RGB corresponding to that bit value has been assigned, and if a specific bit value in the bitmap is 0, the terminal can determine that the RGB corresponding to that bit value has not been assigned.

[0183] In Resource Allocation Type 1, RB allocation information may be notified from the base station to the terminal as information regarding the starting position and length of consecutively allocated VRBs. In this case, interleaving or non-interleaving may be additionally applied to the consecutively allocated VRBs. The resource allocation field of Resource Allocation Type 1 may consist of a resource indication value (RIV), and the RIV is the starting point of the VRB ( ) and the length of consecutively allocated RB ( It can be composed of. More specifically, The RIV within the bandwidth part of the size can be defined as follows.

[0184]

[0185] FIG. 9 is a diagram illustrating an example of downlink data channel processing in a wireless communication system according to one embodiment of the present disclosure.

[0186] A scrambling process can be performed for one codeword or for each of two codewords (901). Length A sequence of codewords q containing scrambling sequence obtained through initialization as in mathematical equation 3 A scrambled sequence using the process as in Equation 2 You can obtain. Its value is set through the upper layer parameter, or otherwise, as the cell ID value. It can be determined, may refer to an RNTI associated with PDSCH transmission.

[0187]

[0188] A sequence of scrambled beats and using one of the various modulation schemes supported by the wireless communication system A modulation symbol sequence having a length (902) can be generated.

[0189] v layers, for each layer Each modulation symbol can be mapped (903), and if this is expressed It is the same as. The relationship between the number of layers, the number of codewords, and the codeword-layer mapping is as shown in Table 12.

[0190] [Table 12]

[0191]

[0192] The modulation symbols mapped to the layer can be mapped to the antenna port as shown in Equation 4. This can be determined by the information included in the DCI format (904).

[0193] [Mathematical Formula 4]

[0194]

[0195] After completing the above process Symbols can be mapped to REs within VRBs allocated for transmission that satisfy conditions for use in PDSCH transmission (e.g., cannot be mapped to DM-RS resources, etc.) (905).

[0196] VRBs that have completed the above process can be mapped to PRBs via an interleaving or non-interleaving mapping method (906). The mapping method can be indicated through the VRB-to-PRB mapping field in the DCI, and if there is no indication of the mapping method, it may mean a non-interleaving mapping method.

[0197] When a non-interleaving mapping method is used, VRB n can be mapped to PRB n, except in specific cases. For example, the aforementioned specific case is when VRB n of a PDSCH scheduled using DCI format 1_0 through the common seek space is PRB ( This may include cases where the above DCI is mapped to the first PRB of the transmitted CORESET.

[0198] When the interleaving mapping method is used, the RBs within the BWP It can be divided into RB bundles, and the RB bundles can be mapped using the method shown in Table 13.

[0199] RBs within BWP One example of dividing into RB bundles could be as follows. Starting point Inside a BWP having The set of RBs is It is divided into RB bundles, and the said RB bundles can be indexed in increasing order. Here, L i represents the bundle size in BWP i, which can be transmitted to the terminal via the upper layer parameter vrb-ToPRB-Interleaver. And, RB Bundle 0 is Consists of RBs, and RB bundle Is If satisfied It consists of RBs and otherwise L i It can consist of RBs. And the remaining RB bundles are L i It can be composed of several RBs.

[0200] [Table 13]

[0201]

[0202] According to one embodiment of the present disclosure, in a 5G NR system, an MCS index for PDSCH, i.e., a modulation order (or method) Qm and a target code rate R, can be determined through the following process.

[0203] [MCS Index Table Determination Method]

[0204] For a PDSCH scheduled via a PDCCH (PDCCH with DCI format 1_0, format 1_1, or format 1_2 with CRC scrambled by C-RNTI, MCS-C-RNTI, TC-RNTI, CS-RNTI, SI-RNTI, RA-RNTI, MSGB-RNTI, or P-RNTI) containing a DCI (e.g., DCI format 1_0, DCI format 1_1, or DCI format 1_2) with a CRC scrambled by C-RNTI, MCS-C-RNTI, TC-RNTI, CS-RNTI, SI-RNTI, RA-RNTI, MSGB-RNTI, or P-RNTI, or for a PDSCH scheduled using a PDSCH configuration SPS-Config (or SPS configuration) provided by an upper layer without a corresponding PDCCH transmission,

[0205] (a) If the higher layer parameter mcs-Table given by PDSCH-Config is set to 'qam256', and the PDSCH is scheduled by a PDCCH with DCI format 1_1 with CRC scrambled by C-RNTI, the terminal uses the MCS index I of [Table 15] to determine the modulation order Qm and the target code rate R. MCS The value can be used.

[0206] (b) If the condition of (a) is not satisfied, and the UE is not configured with MCS-C-RNTI, and the higher layer parameter mcs-Table given by PDSCH-Config is set to 'qam64LowSE', and the PDSCH is scheduled by a PDCCH in a UE-specific search space with a CRC scrambled by C-RNTI, then the UE uses the MCS index I of [Table 16] to determine the modulation order Qm and the target code rate R. MCS The value can be used.

[0207] (c) If the conditions of (a) and (b) are not satisfied, and the UE is configured with MCS-C-RNTI and the PDSCH is scheduled by a PDCCH with CRC scrambled by MCS-C-RNTI, the UE uses the MCS index I of [Table 16] to determine the modulation order Qm and the target code rate R. MCS The value can be used.

[0208] (d) if the conditions of (a), (b), and (c) are not satisfied, and also the UE is not configured with the higher layer parameter mcs-Table given by SPS-Config, and the higher layer parameter mcs-Table given by PDSCH-Config is set to 'qam256',

[0209] (d-1) If the PDSCH is scheduled by a PDCCH with DCI format 1_1 with CRC scrambled by CS-RNTI, or,

[0210] (d-2) When PDSCH is scheduled without a corresponding PDCCH transmission using SPS-Config,

[0211] The terminal uses the MCS index I of [Table 15] to determine the modulation order Qm and target code rate R. MCS The value can be used.

[0212] (e) If the conditions of (a), (b), (c), and (d) are not satisfied, and the UE is configured with the higher layer parameter mcs-Table given by SPS-Config set to 'qam64LowSE',

[0213] (e-1) If the PDSCH is scheduled by a PDCCH with CRC scrambled by CS-RNTI or,

[0214] (e-2) If the PDSCH is scheduled without corresponding PDCCH transmission using SPS-Config,

[0215] The UE uses the MCS index I in [Table 16] to determine the modulation order Qm and target code rate R. MCS The value can be used.

[0216] (f) If the conditions of (a), (b), (c), (d), and (e) are not satisfied, the UE uses the MCS index I of [Table 14] to determine the modulation order Qm and target code rate R. MCS The value can be used.

[0217] MCS Index I MCS Modulation OrderQm Target code Rate [R x 1024] Spectralefficiency 0 2 120 0.2344 1 2 157 0.3066 2 2 193 0.3770 3 2 251 0.4902 4 2 308 0.6016 5 2 379 0.7402 6 2 449 0.8770 7 2 526 1.0273 8 2 602 1.1758 9 2 679 1.3262 10 4 340 1.3281 11 4 378 1.4766 12 4 434 1.6953 13 4 490 1.9141 14 4 553 2.1602 15 4 616 2.4063 16 4 658 2.5703 17 6 438 2.5664 18 6 466 2.7305 19 6 517 3.0293 20 6 567 3.3223 21 6 616 3.6094 22 6 666 3.9023 23 6 719 4.2129 24 6 772 4.5234 25 6 822 4.8164 26 6 873 5.1152 27 6 910 5.3320 28 6 948 5.5547 29 2 reserved 30 4 reserved 31 6 reserved

[0218] MCS Index I MCS Modulation Order Qm Target code Rate [R x 1024] Spectral efficiency 0 2 120 0.2344 1 2 193 0.3770 2 2 308 0.6016 3 2 449 0.8770 4 2 602 1.1758 5 4 378 1.4766 6 4 434 1.6953 7 4 490 1.9141 8 4 553 2.1602 9 4 616 2.4063 10 4 658 2.5703 11 6 466 2.7305 12 6 517 3.0293 13 6 567 3.3223 14 6 616 3.6094 15 6 666 3.9023 16 6 719 4.2129 17 6 772 4.5234 18 6 822 4.8164 19 6 873 5.1152 20 8 682.5 5.3320 21 8 711 5.5547 22 8 754 5.8906 23 8 797 6.2266 24 8 841 6.5703 25 8 885 6.9141 26 8 916.5 7.1602 27 8 948 7.4063 28 2 reserved 29 4 reserved 30 6 reserved 31 8 reserved

[0219] MCS Index I MCS Modulation Order Qm Target code Rate [R x 1024] Spectral efficiency 0 2 30 0.0586 1 2 40 0.0781 2 2 50 0.0977 3 2 64 0.1250 4 2 78 0.1523 5 2 99 0.1934 6 2 120 　0.2344 7 2 157 　0.3066 8 2 193 　0.3770 9 2 251 　0.4902 10 2 308 　0.6016 11 2 379 　0.7402 12 2 449 　0.8770 13 2 526 　1.0273 14 2 602 　1.1758 15 4 340 　1.3281 16 4 378 1.4766 17 4 434 　1.6953 18 4 490 　1.9141 19 4 553 　2.1602 20 4 616 　2.4063 21 6 438 　2.5664 22 6 466 　2.7305 23 6 517 　3.0293 24 6 567 　3.3223 25 6 616 　3.6094 26 6 666 　3.9023 27 6 719 　4.2129 28 6 772 　4.5234 29 2 reserved 30 4 reserved 31 6 reserved

[0220] FIG. 10 is a diagram illustrating an example of a method for obtaining the transport block size (TBS) in a wireless communication system according to one embodiment of the present disclosure.

[0221] The terminal first determines the number of REs (N) within the slot. RE ) can be obtained (determined, or calculated) (1001). The terminal is the number of REs allocated to the PDSCH mapping in one PRB within the allocated resources. Can obtain (calculate). Is It can be calculated as. Here, is 12, and can represent the number of OFDM symbols assigned to PDSCH. is the number of REs of DMRS of the same CDM group within a PRB. is the number of REs occupied by the overhead within the PRB as long as it is set to the upper signaling, and can be set to one of 0, 6, 12, or 18 (it can be set to 0 if it is not set to the upper signaling).

[0222] And, the total number of REs allocated to PDSCH can be calculated. Is It is calculated based on, represents the number of PRBs allocated to the terminal. The value can be calculated as above. Or, N RE Information including all possible cases that can be set to the value of (e.g., may be organized in the form of at least one table) is stored, and , , , , Through at least one parameter value, from the above-mentioned stored information (e.g., a table) The value can be obtained.

[0223] And, the terminal is the number of temporary information bits It can obtain (calculate) (1002). For example, the number of temporary information bits N above. info Is It can be calculated as follows. Here, R represents the coding rate and Qm represents the modulation order, and the information can be determined based on the modulation and coding scheme (MCS) information included in the control information (e.g., DCI, RRC setting information, etc.). Specifically, pre-agreed information regarding the coding rate and modulation order (e.g., MCS index tables such as Tables 12, 13, 14) may be used, and the coding rate and modulation order may be determined based on the MCS information and the pre-agreed information. v may represent the number of allocated layers. The value is calculated as above, or information including all possible cases (e.g., in the form of at least one table) is stored, and from the stored information through at least one parameter value among R, Qm, and v The value can be obtained.

[0224] The terminal acquired (calculated) The value of can be compared with the value of 3824 (1003). Depending on whether the value is 3824 or less or greater, in different ways and TBS can be obtained (calculated) (1004).

[0225] In the case of, and Through the formula can be calculated. The value is calculated as above, or information on all possible cases (e.g., at least one table) is stored, and , n From the stored information through at least one parameter value The value can be obtained. TBS is from Table 17 Among values ​​not smaller than It can be determined as the value closest to .

[0226] [Table 17]

[0227]

[0228] In the case of, and Through the formula can be calculated. The value is calculated as above, or information on all possible cases (e.g., at least one table) is stored, and , n In the above-mentioned stored table through at least one parameter value The value can be obtained. TBS is It can be determined through the value and the pseudo code included in Table 18, or other forms of pseudo code that produce the same result. Alternatively, the above TBS stores information on all possible cases (e.g., at least one table), and R, The TBS value can be obtained from the stored information through at least one parameter value among C.

[0229] [Table 18]

[0230]

[0231] The maximum data rate supported by the terminal in the NR system can be determined through mathematical formula 6.

[0232] [Mathematical Formula 6]

[0233]

[0234] In mathematical equation 6, J is the number of carriers grouped by frequency aggregation, and Rmax = 948 / 1024, is the maximum number of layers, is the maximum modulation order, is the scaling index, can mean the subcarrier spacing. The terminal You can report by setting it to one of the values ​​1, 0.8, 0.75, or 0.4, and It can be given as shown in Table 19.

[0235] [Table 19]

[0236]

[0237] is the average OFDM symbol length, and Is It can be calculated as, is the maximum number of RBs in BW(j). is an overhead value, which can be given as 0.14 for the downlink and 0.18 for the uplink of FR1 (band below 6 GHz), and as 0.08 for the downlink and 0.10 for the uplink of FR2 (band above 6 GHz). For example, through Equation 6, the maximum data rate in the downlink of a cell with a frequency bandwidth of 100 MHz at a subcarrier spacing of 30 kHz can be as shown in Table 20 below.

[0238] [Table 20]

[0239]

[0240] Meanwhile, the actual data rate, which represents the actual data transmission efficiency, can be the value obtained by dividing the amount of transmitted data by the data transmission time. That is, in the case of 1 TB transmission, it can be the value obtained by dividing the sum of 2 TBS or 2 TBS in the case of 2 transmissions by the length of the transmission time interval (TTI). The maximum actual downlink data rate in a cell with a 30 kHz subcarrier spacing and a 100 MHz frequency bandwidth can be determined according to the number of allocated PDSCH symbols as shown in Table 21 below.

[0241] [Table 21]

[0242]

[0243] By referring to the maximum data rate supported by the terminal as shown in Table 20 and the actual data rate according to the allocated TBS as shown in Table 21, it can be seen that there are cases where the actual data rate is greater than the maximum data rate supported by the terminal depending on the scheduling information.

[0244] In wireless communication systems and NR systems, the maximum frequency band, maximum modulation order, and maximum number of layers supported by the terminal can be used to determine (calculate, obtain) the terminal's supported data rate between the base station and the terminal. However, the terminal's supported data rate may differ from the actual data rate calculated based on TBS and TTI, and in some cases, the base station may transmit data to the terminal that has a TBS greater than the terminal's supported data rate.

[0245] According to one embodiment of the present disclosure, a base station may transmit data to a terminal in a 1:1 relationship (uni-cast) or transmit data in a 1:N relationship (multi-cast, group-cast, broadcast-cast, etc.).

[0246] According to one embodiment of the present disclosure, a DCI with a scrambled CRC (a CRC generated using DCI information) based on a group-common RNTI attached can be transmitted through a group-common PDCCH. The DCI can schedule a group-common PDSCH. In this case, the RNTI used in Equation 3 of process 901 may be the group-common RNTI, and the same value may be set for the terminals of the group. Meanwhile, the group-common RNTI of the present disclosure may be a newly defined RNTI for group communication, or it may be an RNTI among the RNTIs set on the terminals that is configured to be used for group communication.

[0247] According to one embodiment of the present disclosure, a DCI terminal-specific PDCCH (UE-specific PDCCH) with a scrambled CRC (CRC generated using DCI information) attached based on a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI) may be transmitted. The DCI may schedule a group-common PDSCH. In this case, the RNTI used in Equation 3 of process 901 may be the group-common RNTI, and the same value may be set for the terminals of the group. Meanwhile, according to one embodiment of the present disclosure, a base station may set an mcs-Table (e.g., Table 14, Table 15, or Table 16) for transmitting a group-common PDSCH to a terminal. In the present disclosure, information regarding at least one modulation order and target code rate that can be determined according to at least one MCS index value may be referred to as mcs-Table information, but it is obvious that it may be referred to by other terms (e.g., MCS-related information). The mcs-Table for group-common PDSCH transmission (mcs-Table for group communication or group common mcs-Table) set on the terminal may be set separately from the mcs-Table (or UE-specific mcs-Table) set for unicast PDSCH. For example, the mcs-Table for group-common PDSCH transmission may be defined (or designed) or set with consideration for lower performance than the mcs-Table for unicast PDSCH.However, one embodiment of the present disclosure is not limited thereto, and the mcs-Table for group common PDSCH transmission may include at least one or at least some of the mcs-Table entries set for unicast PDSCH.

[0248] According to one embodiment of the present disclosure, an mcs-Table setting for group-common PDSCH transmission can be configured per BWP by including it in a PDSCH setting parameter within a BWP setting parameter.

[0249] Specifically, configuration information for a downlink BWP (BWP-Downlink) and configuration information for an uplink BWP (BWP-Uplink) may be configured on a terminal. The downlink BWP may include configuration information for a downlink common BWP (BWP-DownlinkCommon) and a downlink dedicated BWP (BWP-DownlinkDedicated). The downlink common BWP is a cell-specific BWP, and the downlink common BWP configuration information may include parameters that are commonly applied to terminals located within the cell. The downlink specific BWP is a terminal-specific BWP, and the downlink dedicated BWP configuration information may include terminal-dedicated parameters. Meanwhile, in this disclosure, a BWP that includes a group common PDSCH may be referred to as a group common BWP. That is, a group common BWP may refer to a BWP used for one-to-many communication, such as multicast or broadcast. The above group common BWP may be configured on the terminal as a BWP separate from the existing BWP (legacy BWP), or some of the frequency resources of the BWP configured on the terminal may be configured on the terminal as the group common BWP.

[0250] When configured on a terminal as a BWP separate from the legacy BWP, configuration information for the group common BWP may be included within the downlink common BWP, or configuration information for the group common BWP may be defined separately. The configuration information for the group common BWP may include information regarding the group common PDCCH area and information regarding the group common PDSCH area.

[0251] If a specific frequency resource among the BWPs configured in the terminal is configured as a group common BWP in the terminal, for example, the terminal may use all or part of the downlink common BWP as a group common BWP. Alternatively, some of the BWPs or frequency resources among the multiple BWPs configured in the terminal may be used as a group common BWP.

[0252] Accordingly, according to one embodiment of the present disclosure, when a group common BWP is set as a BWP separate from the BWP of a terminal, or when a specific frequency resource among the BWPs set in the terminal is set as a group common BWP, a setting for an mcs-Table may be included within the PDSCH setting information included in the group common BWP setting information.

[0253] According to one embodiment of the present disclosure, an mcs-Table setting for group-common PDSCH transmission can be included in a group-common frequency resource setting parameter for group-common PDSCH transmission within a PDSCH setting parameter and configured for each group-common frequency resource.

[0254] The above group common frequency resource may be composed of a part or all of the resources of the BWP, and in the present disclosure, the above group common frequency resource may be composed of the entire or at least a part of the frequency resources of the above group common BWP. Accordingly, the above group common frequency resource may also be configured as a part of the frequency resources configured in the terminal or as a frequency resource separate from the frequency resources configured in the terminal, and the mcs-Table configuration may be included in the information for configuring the above group common frequency resource.

[0255] According to one embodiment of the present disclosure, a DCI with a scrambled CRC (a CRC generated using DCI information) based on a group-common RNTI attached can be received through a group-common PDCCH. The terminal [receives] a Modulation and coding scheme field (I) included in the DCI. MCS To determine the modulation order (Qm) and target code rate R corresponding to ), an mcs-Table configured for group-common PDSCH transmission may be used. If the mcs-Table configured for group-common PDSCH transmission does not exist, the terminal uses an mcs-Table configured for unicast PDSCH to [use] the Modulation and coding scheme field (I included in the DCI). MCS The modulation order (Qm) and target code rate R corresponding to ) can be determined. At this time, the DCI with a scrambled CRC attached based on the group common RNTI may use a DCI format separately defined for group communication or a DCI format predefined for unicast communication.

[0256] According to one embodiment of the present disclosure, when a terminal receives a PDCCH scheduled through a group-specific search space, the terminal has a Modulation and coding scheme field (I) included in the DCI. MCS To determine the modulation order (Qm) and target code rate R corresponding to ), an mcs-Table configured for group-common PDSCH transmission may be used. If the mcs-Table configured for group-common PDSCH transmission does not exist, the terminal uses an mcs-Table configured for unicast PDSCH to [use] the Modulation and coding scheme field (I included in the DCI). MCS The modulation order (Qm) and target code rate R corresponding to ) can be determined. Meanwhile, for DCI transmitted through a group-specific search space, a DCI format separately defined for group communication or a DCI format predefined for unicast communication may be used.

[0257] According to one embodiment of the present disclosure, a DCI with a scrambled CRC (a CRC generated using DCI information) based on a group-common RNTI attached can be received through a group-specific search space of a group-common PDCCH. The terminal [receives] a Modulation and coding scheme field (I) included in the DCI. MCSTo determine the modulation order (Qm) and target code rate R corresponding to ), an mcs-Table configured for group-common PDSCH transmission may be used. If the mcs-Table configured for group-common PDSCH transmission does not exist, the terminal uses an mcs-Table configured for unicast PDSCH to [use] the Modulation and coding scheme field (I included in the DCI). MCS The modulation order (Qm) and target code rate R corresponding to ) can be determined.

[0258] FIG. 11 is a drawing illustrating the operation of a terminal according to one embodiment of the present disclosure.

[0259] Referring to FIG. 11, the terminal can receive configuration information from a base station. The configuration information can be received via RRC signaling, MIB, or SIB.

[0260] The above-mentioned configuration information may include information regarding BWPs, and in the present disclosure, the above-mentioned configuration information may include information regarding mcs-Tables, etc. As described above, the mcs-Table may include at least one of an mcs-Table configured for unicast PDSCH or an mcs-Table configured for group common PDSCH. As described above, the mcs-Table configured for group common PDSCH may be configured per BWP or per group common frequency resource. In this case, specific details regarding configuration information for BWPs or configuration information for group common frequency resources are the same as described above and are omitted below.

[0261] According to the above embodiments, the terminal can monitor PDCCH in at least one search space (1101). The search space may include a common search space. The common search space may include a group search space that is commonly set up only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space that is commonly set up only for a specific group i for group communication.

[0262] More specifically, the group search space that is commonly set only for the above group i can be obtained by setting the Yp,-1 value of Equation 1 as the group common RNTI and substituting it into Equation 1. A terminal included in the group can monitor the PDCCH in the above group search space, and the information included in the DCI received in the above group search space can be used for the terminal's group communication.

[0263] Alternatively, the base station may transmit information regarding the group search space to the terminal. The base station may set information regarding the PDCCH where the group search space is located (or to be used for group communication) to the terminal via RRC signaling or SIB. In this case, the time resource information and frequency resource information for the CORESET may be directly indicated via RRC signaling, MIB, or SIB. Alternatively, the time resource information and frequency resource information for the PDCCH may be indicated by any one of the predetermined information (e.g., information configured in the form of a table) through the information included in the RRC signaling, MIB, or SIB. Furthermore, the CCE index of the common search space included in the PDCCH may be determined based on the above-described Equation 1.

[0264] As a result of monitoring the terminal, DCI can be detected (1102). That is, as a result of monitoring the PDCCH, the terminal can receive DCI through the PDCCH.

[0265] When a DCI is received, the terminal can check whether the RNTI used for scrambling the CRC of the DCI transmitted through the PDCCH is the first RNTI or the second RNTI (1103). As described above, a terminal included in group i may be assigned a group common RNTI (which may be received via upper layer signaling, MIB, or SIB), and if a group common RNTI is assigned, step 1103 may be performed. In the present disclosure, the second RNTI may refer to the group common RNTI, and the first RNTI may refer to an RNTI other than the group common RNTI set in the terminal. Meanwhile, in the present disclosure, step 1103 may be a step of checking whether the RNTI used for scrambling the CRC of the DCI is the second RNTI. That is, the terminal can check whether a scrambling CRC based on the group common RNTI has been attached, and based on this, check whether scheduling information for group communication has been received.

[0266] However, if the group search space is a search space that is commonly set only for group i based on the group common RNTI, the DCI received in the group search space is a group common DCI, so step 1103 can be omitted.

[0267] Additionally, step 1103 may be changed to a step of determining whether the DCI is for group communication (or whether the DCI is group common or UE-specific).

[0268] If the above RNTI is the first RNTI, the terminal can use the first mcs-Table (or, mcs-Table #1) (1104). That is, the terminal can use the MCS index (I included in the received DCI). MCS At least one of the modulation order (Qm) and target code rate R corresponding to the value of the bit field can be verified.

[0269] If the above RNTI is the second RNTI, the terminal may use the second mcs-Table (or, mcs-Table #2) (1105). That is, the terminal may use the MCS index (I included in the received DCI). MCS At least one of the modulation order (Qm) corresponding to the value and the target code rate R can be verified.

[0270] The terminal determines the modulation order (Qm) and target code rate R of the PDSCH scheduled by the DCI based on the at least one modulation order (Qm) and target code rate R identified above, and can subsequently perform operations such as determining the TBS.

[0271] The first mcs-Table above may correspond to an mcs-Table set for unicast PDSCH, and the second mcs-Table above may correspond to an mcs-Table set for group common PDSCH.

[0272] FIG. 12 is a diagram illustrating the DCI generation operation of a base station according to one embodiment of the present disclosure.

[0273] Referring to FIG. 12, the base station can transmit configuration information to the terminal (1201). The configuration information may refer to information transmitted via RRC signaling, MIB, or SIB.

[0274] The above-mentioned configuration information may include information regarding BWPs, and in this disclosure, the above-mentioned configuration information may include information regarding mcs-Tables, etc. As described above, the mcs-Table may be at least one of an mcs-Table configured for unicast PDSCH or an mcs-Table configured for group common PDSCH. As described above, the mcs-Table configured for group common PDSCH may be configured per BWP or per group common frequency resource. In this case, specific details regarding configuration information for BWPs or configuration information for group common frequency resources are the same as described above and are omitted below.

[0275] And, the base station can determine the type of DCI to transmit (1202). However, step 1202 may be omitted. Specific details will be described later.

[0276] Specifically, the base station may determine the type of DCI based on the data to be transmitted via PDSCH (or based on whether the data is for group communication, or whether the data is group common data or UE-specific data). For example, the type of DCI may be determined based on whether the data is transmitted to a single terminal or to terminals belonging to a specific group (i.e., multiple terminals). The base station determines the modulation order (Qm) and target code rate R of the data to be transmitted via PDSCH, and an MCS index (I) for indicating the modulation order (Qm) and / or target code rate R. MCSThe value of ) can be determined. At this time, the MCS index may be determined using different mcs-Tables depending on the data (i.e., whether the data is transmitted for group communication or for unicast transmission) or the type of the determined DCI, and specific details will be described later. However, as described above, the type (or format) of the DCI for group communication and the type (or format) of the DCI for unicast communication may be the same, and in such a case, step 1202 may be omitted.

[0277] Alternatively, the base station may determine the type of DCI based on whether the DCI to be transmitted via PDCCH is for group communication (or whether the DCI is group common or UE-specific) (1202). For example, the DCI may be for a single terminal (UE-specific) or a specific group (group-common). Accordingly, the base station determines the modulation order (Qm) and target code rate R of the data to be transmitted via the PDSCH scheduled by the DCI, and an MCS index (I) for indicating the modulation order (Qm) and / or target code rate R. MCS The value of ) can be determined. At this time, the MCS index may be determined using different mcs-Tables depending on the type of DCI determined above, and specific details will be described later. However, as described above, the type (or format) of DCI for group communication and the type (or format) of DCI for unicast communication may be the same, and in such cases, step 1202 may be omitted.

[0278] If the determined DCI is UE-specific, the base station can generate a DCI using a first mcs-Table (mcs-Table #1) (1203), generate a CRC using the generated DCI, and scramble the CRC using a first RNTI (1205). The first mcs-Table may be an mcs-Table set for a terminal for unicast PDSCH through the process of 1201, and the RNTI may be a terminal-specific RNTI (UE-specific RNTI), for example, including a C-RNTI. The base station can transmit the DCI and CRC generated as above through PDCCH.

[0279] If the type of the determined DCI is group-common, the base station can generate a DCI using a second mcs-Table (1204), generate a CRC using the generated DCI, and scramble the CRC using a second RNTI (1206). The second mcs-Table may be an mcs-Table set in the terminal for a group-common PDSCH through the process of 1201, and the RNTI may include a group-common RNTI. The base station can transmit the DCI and CRC generated as above through the PDCCH. The PDCCH may be transmitted by mapping to a common search space or a group search space.

[0280] According to one embodiment of the present disclosure, a group-common PDSCH may be used for retransmission of data transmitted through a group-common PDSCH.

[0281] According to one embodiment of the present disclosure, a terminal-specific PDSCH (UE-specific PDSCH) scheduled via a terminal-specific PDCCH (UE-specific PDSCH) may be used for retransmission of data transmitted via a group-common PDSCH (group-common PDSCH).

[0282] According to one embodiment of the present disclosure, a group-common PDSCH scheduled via a UE-specific PDCCH may be used for retransmission of data transmitted via a group-common PDSCH.

[0283] According to one embodiment of the present disclosure, whether to retransmit a TB transmitted through a group common PDSCH can be determined by a first HARQ process number and a first NDI (New Data Indicator) value included in a first DCI using a first RNTI (used for scrambling a CRC generated using a first DCI) transmitted through a first PDCCH that schedules a first PDSCH, and a second HARQ process number and a second NDI value included in a second DCI using a second RNTI (used for scrambling a CRC generated using a second DCI) transmitted through a second PDCCH that schedules a second PDSCH.

[0284] More specifically, regardless of whether the first RNTI and the second RNTI are the same, if the first HARQ process number and the second HARQ process number are the same and the second NDI value is the same as the first NDI value, the data (TB) transmitted through the second PDSCH is determined to be a retransmission of the data (TB) transmitted through the first PDSCH, and a subsequent operation (e.g., combining) can be performed accordingly. That is, even if the first RNTI and the second RNTI are different RNTIs (e.g., terminal-specific RNTI and terminal-common RNTI), if the number of the HARQ process included in the DCI is the same and the NDI value is not toggled, an operation for TB retransmission can be performed. Alternatively, if the first RNTI and the second RNTI are the same RNTI (e.g., terminal common RNTI), and the number of the HARQ process included in the DCI is the same and the NDI value is not toggled, the data transmitted through the second PDSCH may be understood as retransmitted data. On the other hand, if the second NDI value is different from the first NDI value (i.e., toggled), the data (TB) transmitted through the second PDSCH may be understood as new data. The first RNTI may be, for example, a group common RNTI, and the second RNTI may be a terminal specific RNTI (UE-specific RNTI, C-RNTI). As another example, the first RNTI may be a group common RNTI, and the second RNTI may also be a group common RNTI. According to one embodiment of the present disclosure, the determination of whether to retransmit, as in the above embodiment, may be performed per MAC entity.

[0285] FIG. 13 is a drawing illustrating an example of a downlink data channel of a terminal according to one embodiment of the present disclosure.

[0286] Referring to FIG. 13, the terminal can monitor PDCCH in at least one search space according to the embodiments above (not shown). The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0287] As a result of the above monitoring, the terminal can receive a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1) (1301). The first RNTI (RNTI #1) is a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH.

[0288] Additionally, the terminal may receive a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2), in which the CRC is scrambled by a second RNTI (RNTI #2) (1302). The second RNTI (RNTI #2) is a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH.

[0289] Meanwhile, steps 1301 and 1302 above may be changed according to embodiments of the present disclosure. That is, the order of steps 1301 and 1302 may be changed, or the terminal may receive a first DCI scrambled with a first RNTI in steps 1301 and 1302, or the terminal may receive a second DCI scrambled with a second RNTI in steps 1301 and 1302. Alternatively, steps 1301 and 1302 may be changed to steps of receiving the first DCI and the second DCI, respectively, and the first DCI and the second DCI may not be limited to a specific RNTI. Furthermore, the terminal may determine whether to retransmit based on whether the NDI value is toggled for the same HARQ process number as described below. At this time, if the NDI value is not toggled for the same HARQ process number, the terminal can perform retransmission regardless of the RNTI associated with the DCI.

[0290] Specifically, the terminal can compare the HARQ process number of the second DCI (DCI #2) with the HARQ process number of the first DCI (DCI #1). If the HARQ process number values ​​of the two DCIs are the same, the terminal can compare the first NDI value included in the second DCI (DCI #2) with the second NDI value included in the first DCI (DCI #1) to determine whether the second NDI value has been toggled (e.g., changed from 0 to 1, or from 1 to 0) (1303).

[0291] Depending on whether the second NDI value is toggled, the terminal may understand the data included in the second PDSCH scheduled by DCI #2 as a new transmission if it is toggled, and proceed with subsequent processing (1304). The processing may include, for example, the calculation of TBS, the flush operation of a buffer corresponding to the HARQ process number, etc.

[0292] Depending on whether the second NDI value is toggled, if it is not toggled, i.e., if the values ​​are the same, the terminal can understand the data included in the second PDSCH scheduled by DCI #2 as a retransmission of the first PDSCH #1 and proceed with subsequent processing (1305). The processing may include, for example, the calculation of the TBS, combining the LLR values ​​of the first PDSCH #1 and the second PDSCH #2. That is, even if the value of the first RNTI scrambled with the CRC of the first DCI scheduled by the first PDSCH #1 and the value of the second RNTI scrambled with the CRC of the second DCI scheduled by the second PDSCH #2 are different, the terminal can determine whether to retransmit based on the HARQ process number included in each DCI and whether the NDI value is toggled, and then perform processing of the PDSCH.

[0293] According to one embodiment of the present disclosure, the same operation as in FIG. 13 can be performed even when the first RNTI (RNTI #1) and the second RNTI (RNTI #2) of FIG. 13 are the same, and if the terminal succeeds in receiving and decoding the first PDSCH #1, the terminal may not perform the processing operation (1305) of the second PDSCH.

[0294] The operation of the base station accordingly may be as follows. According to the embodiments, the base station may transmit DCI through at least one search space. The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0295] At this time, the base station may transmit a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1). The first RNTI (RNTI #1) may be a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH. Additionally, the base station may transmit a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2), in which the CRC is scrambled by a second RNTI (RNTI #2). The second RNTI (RNTI #2) may be a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH. Meanwhile, the above-mentioned first DCI and second DCI may not be limited to a specific RNTI.

[0296] In addition, if the base station intends to retransmit data transmitted from the first PDSCH to the second PDSCH, it may transmit to the terminal by setting the NDI value to be the same for the same HARQ process number, regardless of the values ​​of the RNTI used in the first DCI and the second DCI. Meanwhile, if the base station intends to transmit new data from the second PDSCH, it may transmit to the terminal by changing (toggling) the NDI value included in the second DCI.

[0297] According to one embodiment of the present disclosure, a Modulation and coding scheme field (I) included in a DCI transmitted via a terminal-specific PDCCH (UE-specific PDCCH, scrambling CRC via UE-specific RNTI) that directs retransmission to a group-common PDSCH (group-common PDSCH) MCS The mcs-Table used to determine the modulation order (Qm) and target code rate R corresponding to ) can be determined through the method for determining the MCS index table of the above embodiment.

[0298] According to one embodiment of the present disclosure, a Modulation and coding scheme field (I) included in a DCI transmitted via a group-common PDCCH (group-common PDCCH, scrambling CRC through a group-common RNTI) that directs retransmission to a group-common PDSCH (group-common PDSCH) MCS The mcs-Table used to determine the modulation order (Qm) and target code rate R corresponding to ) may be the mcs-Table set for group common PDSCH transmission of the above embodiment.

[0299] Meanwhile, according to one embodiment of the present disclosure, the mcs-Table and I determined through the above embodiments MCS TBS can be determined using at least some of the values, etc.

[0300] Specifically, if the code rate indicated by the MCS index included in the DCI is reserved (or if the MCS index indicates reserved), the terminal may set the value of the TBS scheduled by the DCI to be the same as the value of the most recently transmitted TBS. In this case, the TB scheduled by the DCI may be a retransmission of the most recently transmitted TB or a TB for a new transmission.

[0301] Specifically, according to one embodiment of the present disclosure, Table 15 is a Modulation and coding scheme field (I) within the first DCI. MCS Used as an mcs-Table for the value of ), and I included in the first DCI received by the terminal MCS If the value of is 28 or greater and 31 or less (i.e., if the MCS index included in the above DCI indicates reserved), the size of the TB (TBS) scheduled through the above first DCI is the MCS index (I) corresponding to the value of 0 or greater and 27 or less in Table 15, the value of 0 or greater and 28 or less in Table 14, or the value of 0 or greater and 28 or less in Table 16. MCS It may be equal to the TBS determined by the second DCI transmitted through the latest PDCCH transmitted for the same TB, which includes )(i.e., an MCS index that does not indicate the code rate reserved).

[0302] According to one embodiment of the present disclosure, Table 14 or Table 16 is a Modulation and coding scheme field (I) in the first DCI. MCS Used as an mcs-Table for the value of ), and I included in the first DCI received by the terminal MCSIf the value of is 29 or greater and 31 or less (or if the MCS index indicates reserved), the size of the TB (TBS) scheduled through the first DCI is the MCS index (I) corresponding to the value of 0 or greater and 28 or less in Table 14, or the value of 0 or greater and 28 or less in Table 16, or the value of 0 or greater and 27 or less in Table 15. MCS It may be the same as the TBS determined by the second DCI transmitted through the most recent PDCCH (the latest PDCCH) transmitted for the same TB, including ).

[0303] FIG. 14 is a drawing illustrating an example of a method for obtaining the size of a transport block of a terminal according to one embodiment of the present disclosure.

[0304] Referring to FIG. 14, the terminal can monitor PDCCH in at least one search space according to the embodiments above (not shown). The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0305] As a result of the above monitoring, the terminal can receive a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1) (1401). The first RNTI (RNTI #1) is a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH.

[0306] Additionally, the terminal may receive a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2), in which the CRC is scrambled by a second RNTI (RNTI #2) (1402). The second RNTI (RNTI #2) is a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH.

[0307] The terminal, for example, through a process such as that shown in FIG. 11, has an MCS index (I) included in the second DCI (DCI #2). MCS A mcs-table can be determined to determine the modulation order (Qm) and target code rate R corresponding to the value of ) (1403). For example, the mcs-table can be determined based on used for scrambling the received DCI. For example, if scrambling is based on the second RNTI, the mcs-table may correspond to the mcs-table set for unicast PDSCH.

[0308] Meanwhile, steps 1401 and 1402 may be changed according to embodiments of the present disclosure. That is, the order of steps 1401 and 1402 may be changed, or the terminal may receive a first DCI scrambled with a first RNTI in steps 1401 and 1402, or the terminal may receive a second DCI scrambled with a second RNTI in steps 1401 and 1402. Alternatively, steps 1401 and 1402 may be changed to steps of receiving the first DCI and the second DCI, respectively, and the first DCI and the second DCI may not be limited to a specific RNTI. As described below, if the value of the MCS index included in the second DCI is greater than or equal to a predetermined value or a specific value, the terminal can determine that the TBS transmitted through the second PDSCH scheduled by the second DCI is the same as the TBS transmitted through the first PDSCH scheduled by the first DCI.

[0309] Specifically, the terminal is I included in the second DCI MCS It can be determined whether the value of is greater than or equal to a specific value 1 (threshold value 1 or value 1) (1404). The specific value may be determined by the mcs-Table determined in the process of 1403. For example, if the mcs-Table corresponds to Table 15, the specific value may be 28, and if it corresponds to Table 14 or Table 16, the specific value may be 29. Additionally, if a group common mcs-Table is set separately, the specific value may be a value where the target code rate and spectral efficiency of the mcs-Table are reserved.

[0310] The terminal, according to process 1404, I included in the second DCI MCSIf the value of is greater than or equal to a specific value 1, the TBS of the second PDSCH scheduled through the second DCI is the mcs-Table corresponding to the first DCI and I included in the first DCI MCS It can be determined as the same as the TBS determined by the value of (1405). The mcs-Table corresponding to the first DCI may be the mcs-Table set by the base station for group common PDSCH transmission.

[0311] If the mcs-Table corresponding to the first DCI is Table 15, the I included in the first DCI MCS The value of can have a value between 0 and 27, and if the mcs-Table corresponding to the first DCI is Table 14, the I included in the first DCI MCS The value of can have a value between 0 and 28, and if the mcs-Table corresponding to the first DCI is Table 16, the I included in the first DCI MCS The value of the bit field can have a value between 0 and 28. In addition, if a group-common mcs-Table is separately configured, the I included in the first DCI MCS The value of can be a non-reserved value for the target code rate and spectral efficiency of the mcs-Table.

[0312] The terminal, according to process 1404, I included in the second DCI MCS If the value of is less than a specific value 1, the mcs-Table corresponding to the second DCI and I included in the second DCI MCS TBS can be determined (calculated) based on the value of (1406).

[0313] The operation of the base station accordingly may be as follows. The base station may transmit DCI in at least one search space according to the embodiments. The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0314] At this time, the base station may transmit a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1). The first RNTI (RNTI #1) may be a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH. Additionally, the terminal may transmit a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2), in which the CRC is scrambled by a second RNTI (RNTI #2). The second RNTI (RNTI #2) may be a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH.

[0315] And, the base station has an MCS index (I) corresponding to the modulation order (Qm) to be included in the second DCI and the target code rate R. MCSAn mcs-table can be determined to determine the value of ). For example, the base station can check whether the second DCI is a group common DCI or a unicast DCI. Alternatively, the base station can check whether the second PDSCH scheduled by the second DCI is a group common PDSCH or a unicast PDSCH. For example, if it is a group common DCI or a group common PDSCH, the base station can determine the MCS index using an mcs-table set for the group common PDSCH. Meanwhile, the first DCI and the second DCI may not be limited to a specific RNTI.

[0316] In addition, the base station is I included in the first DCI MCS When transmitting data having a TBS equal to the TBS determined by the value of , the base station may set the value of the MCS index included in the second DCI to a specific value 1 (threshold value 1 or value 1) or higher. The specific value may be determined by the determined mcs-Table. For example, if the mcs-Table corresponds to Table 15, the specific value may be 28, and if it corresponds to Table 14 or Table 16, the specific value may be 29. Additionally, if a group common mcs-Table is set separately, the specific value may be a value where the target code rate and spectral efficiency of the mcs-Table are reserved.

[0317] Meanwhile, if the base station intends to transmit data having a TBS different from the TBS determined by the value of the MCS index included in the first DCI, or if it intends to transmit new data, the base station may set the value of the MCS index included in the second DCI to less than a specific value 1.

[0318] According to one embodiment of the present disclosure, the scheduled instantaneous data rate is given by Equation 7. L represents the number of OFDM symbols allocated to the PDSCH, and M represents the number of TBs transmitted in the PDSCH. Is It can be calculated as, represents the subcarrier spacing used for PDSCH transmission. For the m-th TB, Is It can be calculated as follows, where A is the size of the TB (TBS), C is the number of code blocks (CB) included in the TB, and C' is the number of scheduled code blocks in the TB. In the case of CBG (code block group) retransmission, C and C' may be different. represents the largest integer not greater than x.

[0319] [Mathematical Formula 7]

[0320]

[0321] According to one embodiment of the present disclosure, the maximum data rate DataRateCC supported by a terminal in a carrier or serving cell may be determined based on Equation 6 or calculated as in Equation 8. Equation 8 represents an example of calculating the DataRateCC of the j-th serving cell. The parameters included in Equation 8 are omitted here as they have been described in Equation 6.

[0322] [Mathematical Formula 8]

[0323]

[0324] According to one embodiment of the present disclosure, the instantaneous data rate transmitted from J serving cells is as shown in Equation 9.

[0325] [Mathematical Formula 9]

[0326]

[0327] According to one embodiment of the present disclosure, by comparing the value of Equation 9 with the value of Equation 6, it can be determined whether the actual instantaneous data rate in the carriers or serving cells set in the terminal satisfies the capability of the terminal in said carriers or said serving cells. The comparison may be a condition applicable in all cases, including initial transmission and retransmission. That is, if the value of Equation 9 (instant data rate for the serving cell(s)) is less than or equal to the value of Equation 6 (maximum data rate supported by the terminal in the serving cell(s)), the terminal may receive and decode the PDSCH and feed back HARQ-ACK information. Otherwise (i.e., when the instantaneous data rate for the serving cell(s) is greater than the maximum data rate supported by the terminal in the serving cell(s)), the terminal may ignore the information scheduling the PDSCH, not receive the PDSCH, not perform decoding of the PDSCH, set the HARQ-ACK information to NACK, or not feed back the HARQ-ACK information.

[0328] According to one embodiment of the present disclosure, a base station can check the maximum data rate (value of Equation 6) supported by the terminal in the serving cell(s) for each of the terminals belonging to a group, check the minimum value of the maximum data rate (minimum value among the values ​​of Equation 6), and schedule a group common PDSCH to the group of terminals through a group common PDCCH so that the value of the instantaneous data rate (Equation 9) for the serving cell(s) is less than or equal to the minimum value of the maximum data rate (minimum value of Equation 6) for each of the terminals belonging to the group.

[0329] According to one embodiment of the present disclosure, if the instantaneous data rate (value of Equation 9) for the serving cell(s) is less than or equal to the value of the maximum data rate supported by the terminal in the serving cell(s) (or the value of the maximum data rate for a plurality of terminals (value of Equation 6)), the terminal may receive and decode the group common PDSCH and feed back HARQ-ACK information. Otherwise, the terminal may ignore the information that scheduled the group common PDSCH, not receive the group common PDSCH, not perform decoding of the group common PDSCH, set the HARQ-ACK information to NACK, or not feed back HARQ-ACK information.

[0330] According to one embodiment of the present disclosure, by comparing the value of Equation 7 and the value of Equation 8, it can be determined whether the actual instantaneous data rate in one carrier or serving cell satisfies the capability of the terminal in said carrier or serving cell. The comparison may be a condition applied to retransmission. That is, if the value of the instantaneous data rate in one carrier or serving cell (the value of Equation 7) is less than or equal to the maximum data rate supported by the terminal in one carrier or serving cell (the value of Equation 8), the terminal may receive and decode the PDSCH and feed back HARQ-ACK information. Otherwise, the terminal may ignore the information that scheduled the PDSCH, not receive the PDSCH, not perform decoding of the PDSCH, set the HARQ-ACK information to NACK, or not feed back the HARQ-ACK information.

[0331] According to one embodiment of the present disclosure, a base station can check the value of the maximum data rate supported by the terminal in one carrier or serving cell for each of the terminals belonging to one group (value of Equation 8), check the minimum value of the maximum data rate for the terminals (minimum value among the values ​​of Equation 8 for each of the terminals), and schedule a group common retransmission PDSCH to the group of terminals through a group common PDCCH or a terminal-specific PDCCH so that the value of the instantaneous data rate in one carrier or serving cell (value of Equation 7) is less than or equal to the minimum value of the maximum data rate for the terminals belonging to the group in one carrier or serving cell (minimum value of Equation 6).

[0332] According to one embodiment of the present disclosure, if the value of the instantaneous data rate in one carrier or serving cell is less than or equal to the minimum value of the maximum data rate for the terminals, the terminal may receive and decode a group common retransmission PDSCH and feed back HARQ-ACK information. Otherwise, the terminal may ignore the information scheduling the group common retransmission PDSCH, not receive the group common retransmission PDSCH, not perform decoding of the group common retransmission PDSCH, set the HARQ-ACK information to NACK, or not feed back HARQ-ACK information.

[0333] According to one embodiment of the present disclosure, a base station identifies terminals within a group that have fed back a NACK for a group common PDSCH transmission, checks the values ​​of the maximum data rate supported by the terminal in one carrier or serving cell for each of the terminals (values ​​of Equation 8 for each of the terminals), and can schedule terminal-specific retransmission PDSCHs for each of the terminals through terminal-specific PDSCHs so that the instantaneous data rates in one carrier or serving cell for each of the terminals (values ​​of Equation 7) are less than or equal to the values ​​of the maximum data rate for each of the terminals (values ​​of Equation 8).

[0334] According to one embodiment of the present disclosure, if the instantaneous data rate (value of Equation 7) in one carrier or serving cell is less than or equal to the maximum data rate (value of Equation 8) in one carrier or serving cell, the terminal may receive and decode a terminal-specific retransmission PDSCH transmitted as a retransmission for a group common PDSCH transmission and feed back HARQ-ACK information. Otherwise, the terminal may ignore the information scheduling the terminal-specific retransmission PDSCH transmitted as a retransmission for the group common PDSCH transmission, or not receive or decode the terminal-specific retransmission PDSCH transmitted as a retransmission for the group common PDSCH transmission, or set the HARQ-ACK information to NACK, or not feed back HARQ-ACK information.

[0335] There may be many cases where retransmission cannot be scheduled due to scheduling constraints of the base station or the operation of the terminal, such as in the above embodiments of the present disclosure.

[0336] According to one embodiment of the present disclosure, if the mcs-Table set in the DCI scheduling the retransmission is Table 14 or Table 16, I MCS When the value is between 29 and 31, case I in Table 15 MCSWhen the value is between 28 and 31, or when a newly added mcs-Table (or an mcs-Table defined for group communication) is used and the I included in the received DCI MCS If the value corresponds to the Target code rate and spectral efficiency of the newly added mcs-Table being reserved, the terminal may understand the DCI as a DCI instructing retransmission. Also, other I MCS Even if a value is used, retransmission may be performed if the conditions according to the above embodiments are satisfied.

[0337] According to one embodiment of the present disclosure, when a base station performs retransmission of a group-common PDSCH transmitted to a terminal or a group of terminals, the consideration of the scheduling constraints disclosed in the embodiments (e.g., comparison of the instantaneous data rate and the maximum data rate supported by the terminal, or comparison of the value of Equation 7 and the value of Equation 8) may be limited to specific cases.

[0338] For example, it may be limited to cases where the number of symbols L assigned to a PDSCH common to the retransmission group or a specific PDSCH of the retransmission terminal is smaller than a specific number of symbols (e.g., 7). That is, if the above condition is not satisfied, a method may be included that does not consider constraints on the scheduling (e.g., comparison of the instantaneous data rate and the maximum data rate supported by the terminal, or comparison of the value of Equation 7 and the value of Equation 8).

[0339] As another example, the method may be limited to cases where the number of symbols L assigned to a PDSCH common to the retransmission group or a specific PDSCH of the retransmission terminal is smaller than the number of symbols L used for the initial transmission of the PDSCH common to the group. That is, if the above condition is not satisfied, the method may include not considering constraints on the scheduling (comparison of the instantaneous data rate and the maximum data rate supported by the terminal, or comparison of the value of Equation 7 and the value of Equation 8).

[0340] As another example, the method may be limited to cases where the number of symbols L assigned to a PDSCH common to the retransmission group or a specific PDSCH of the retransmission terminal is smaller than the number of symbols L used for the initial transmission of the group common PDSCH and smaller than a specific number of symbols (e.g., 7). That is, if the above conditions are not satisfied, the method may include not considering constraints on the scheduling (e.g., comparison of the instantaneous data rate and the maximum data rate supported by the terminal, or comparison of the value of Equation 7 and the value of Equation 8).

[0341] As another example, the method may be limited to cases where the number of symbols L assigned to a PDSCH common to the retransmission group or a specific PDSCH of the retransmission terminal is smaller than the number of symbols Lx used for the initial transmission of the group common PDSCH (the value of x may be a fixed value such as, for example, 2 or 3, or can be set by the base station through upper signaling). That is, if the above condition is not satisfied, the method may not consider constraints on the scheduling (comparison of the instantaneous data rate and the maximum data rate supported by the terminal, or comparison of the value of Equation 7 and the value of Equation 8).

[0342] According to one embodiment of the present disclosure, when calculating the number of symbols used for PDSCH mapping, or the number of symbols allocated for PDSCH transmission, or the number of symbols used for PDSCH transmission in the examples above, demodulation reference signal (DMRS) symbols for PDSCH may also be included. That is, all symbols for PDSCH transmission transmitted to a DCI or upper signaling indicating PDSCH mapping information may be counted.

[0343] FIG. 15 is a drawing illustrating an example of a downlink data channel of a terminal according to one embodiment of the present disclosure.

[0344] Referring to FIG. 15, the terminal can monitor PDCCH in at least one search space according to the embodiments above (not shown). The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0345] As a result of the above monitoring, the terminal can receive a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1) (1501). The first RNTI (RNTI #1) is a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH.

[0346] Additionally, the terminal may receive a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2) corresponding to a retransmission of the first PDSCH (PDSCH #1), the CRC of which is scrambled by the second RNTI (RNTI #2) (1502). The second RNTI (RNTI #2) is a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH.

[0347] Meanwhile, steps 1501 and 1502 above may be changed according to embodiments of the present disclosure. That is, the order of steps 1501 and 1502 may be changed, or the terminal may receive a first DCI scrambled with a first RNTI in steps 1501 and 1502, or the terminal may receive a second DCI scrambled with a second RNTI in steps 1501 and 1502. Alternatively, steps 1501 and 1502 may be changed to steps of receiving the first DCI and the second DCI, respectively, and the first DCI and the second DCI may not be limited to a specific RNTI. Furthermore, the terminal may determine whether to process the second PDSCH based on information regarding time domain resource assignment as described below.

[0348] The terminal can determine whether a specific condition is satisfied by using at least one of the time resource allocation information included in the first DCI (hereinafter, information of time domain resource assignment) and the information of time domain resource assignment included in the second DCI (1503). The above specific condition may correspond to one of the following conditions, for example: "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than a specific number of symbols"; "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols L assigned to the first PDSCH through the time domain resource assignment included in the first DCI"; "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols L assigned to the first PDSCH through the time domain resource assignment bit field included in the first DCI and a specific number of symbols"; or "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols Lx assigned to the first PDSCH through the time domain resource assignment included in the first DCI (the value of x may be a fixed value such as 2 or 3, for example, or may be set by the base station through upper signaling).

[0349] If certain conditions are not satisfied during the process of 1503, the terminal can perform the processing of the second PDSCH regardless of the constraints on the scheduling (e.g., the result of comparing the instantaneous data rate and the maximum data rate supported by the terminal with the result of comparing the result of Equation 7 and the result of Equation 8) (1505).

[0350] If it is determined that a specific condition is satisfied during the process of 1503, the terminal can check whether the constraints on the above scheduling are satisfied. That is, the terminal can check whether the instantaneous data rate (e.g., the result of Equation 7) is less than or equal to the maximum data rate supported by the terminal (e.g., the result of Equation 8) (1504). If the instantaneous data rate (e.g., the result of Equation 7) is less than or equal to the maximum data rate supported by the terminal (e.g., the result of Equation 8), the terminal can perform the processing of the second PDSCH (1505).

[0351] If the instantaneous data rate (e.g., the result of Equation 7) is greater than the maximum data rate supported by the terminal (e.g., the result of Equation 8), the terminal may ignore the second DCI (1506). That is, the processing of the second PDSCH scheduled by the second DCI may not be performed.

[0352] The operation of the base station accordingly may be as follows. The base station may transmit DCI in at least one search space according to the above embodiments. The search space may include a common search space. The common search space may include a group search space commonly configured only for a specific group i for group communication. Additionally, the search space may include a UE-specific search space. The UE-specific search space may include a group search space commonly configured only for a specific group i for group communication.

[0353] At this time, the base station may transmit a first DCI (DCI #1) that schedules a first PDSCH (PDSCH #1), in which the CRC is scrambled by a first RNTI (RNTI #1). The first RNTI (RNTI #1) may be a group common RNTI, and the first PDSCH (PDSCH #1) may correspond to a group common PDSCH. Additionally, the base station may transmit a second DCI (DCI #2) that schedules a second PDSCH (PDSCH #2), which corresponds to a retransmission of the first PDSCH (PDSCH #1), in which the CRC is scrambled by a second RNTI (RNTI #2). The second RNTI (RNTI #2) may be a terminal-specific RNTI (UE-specific RNTI, e.g., C-RNTI), and the second PDSCH (PDSCH #2) may correspond to a terminal-specific PDSCH. Meanwhile, the above-mentioned first DCI and second DCI may not be limited to a specific RNTI.

[0354] And, the base station can transmit data to the above terminal.

[0355] At this time, if a specific condition is not satisfied based on at least one of the information on the time domain resource assignment included in the first DCI and the information on the time domain resource assignment included in the second DCI, the data may be processed regardless of scheduling constraints. Accordingly, the base station may set the information on the time domain resource assignment included in the DCI to ensure that the data is processed regardless of scheduling constraints. Meanwhile, if the specific condition is satisfied, the terminal may process the data based on the scheduling constraints. The above specific conditions are, for example, "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than a specific number of symbols" or "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols L assigned to the first PDSCH through the time domain resource assignment included in the first DCI" or "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols L assigned to the first PDSCH through the time domain resource assignment bit field included in the first DCI and a specific number of symbols" or "when the number of symbols L assigned to the second PDSCH through the time domain resource assignment included in the second DCI is smaller than the number of symbols Lx assigned to the first PDSCH through the time domain resource assignment included in the first DCI (the value of x may be a fixed value such as, for example, 2 or 3, or may be set by the base station through upper signaling."It may meet one of the conditions when it is smaller than the number.

[0356] According to one embodiment of the present disclosure, a terminal checks whether a scrambled CRC is attached based on a group common RNTI, and if it is confirmed based on this whether scheduling information for group communication is received, it can (re)start a bwp-InactivityTimer associated with a BWP to which the group common PDSCH scheduled by the scheduling information for group communication belongs. When the bwp-InactivityTimer expires, if defaultDownlinkBWP is set, the BWP is changed to defaultDownlinkBWP, and if it is not set, the BWP can be changed to initialDownlinkBWP.

[0357] FIG. 16 is a drawing illustrating the structure of a terminal according to one embodiment of the present disclosure.

[0358] Referring to FIG. 16, the terminal may include a transceiver (1610), a control unit (1620), and a storage unit (1^30). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

[0359] The transceiver (1610) can transmit and receive signals with other network entities. The transceiver (1610) can receive configuration information from a base station, for example, and said configuration information can be received via RRC signaling, MIB, or SIB. said configuration information may include information about BWP and information about mcs-Table. The transceiver (1610) can receive DCI via a group common PDCCH or a group specific PDCCH. Additionally, the transceiver (1610) can receive data from a base station. The transceiver (1610) can receive new transmission data or retransmission data from a base station.

[0360] The control unit (1620) can control the overall operation of the terminal according to the embodiment proposed in the present invention. For example, the control unit (1620) can control the signal flow between each block to perform operations according to the flowchart described above. For example, the control unit (1620) can check whether the received DCI is for group communication. The control unit (1620) can check whether the DCI is for group communication based on whether the CRC included in the DCI was scrambled based on the first RNTI or the second RNTI. At this time, the first RNTI and the second RNTI may each include either a terminal-specific RNTI (e.g., C-RNTI) or a group-common RNTI. And, the control unit (1620) can use different mcs-Tables depending on whether the DCI is for group communication or unicast communication (or whether the DCI is group common or UE-specific). That is, if the DCI is UE-specific, the terminal can use the first mcs-Table to determine at least one of the modulation order and the target code rate. Additionally, if the DCI is group common, the terminal can use the second mcs-Table to determine at least one of the modulation order and the target code rate.

[0361] Additionally, even when the control unit (1620) receives a DCI containing a CRC scrambled with different RNTIs, if the number of the HARQ process included in the DCI is the same and the NDI value is not toggled, the control unit (1620) can understand the received data as retransmitted data and perform subsequent operations. On the other hand, if the NDI value is toggled, the control unit (1620) can understand the received data as new data.

[0362] Additionally, if the code rate indicated by the MCS index included in the DCI indicates the target code rate and spectral efficiency value of the mcs-Table defined for unicast communication or the mcs-Table defined for group communication as reserved, the control unit (1620) can set the value of the TBS scheduled by the DCI to be the same as the value of the most recently transmitted TBS.

[0363] Additionally, when the instantaneous data rate is less than or equal to the maximum data rate, the control unit (1620) may receive and decode the group common retransmission PDSCH or the terminal specific retransmission PDSCH as a retransmission for the group common PDSCH or the terminal specific PDSCH, and feed back HARQ-ACK information. Meanwhile, when the instantaneous data rate is greater than the maximum data rate, the control unit may ignore the information for scheduling the retransmission PDSCH, not receive the retransmission PDSCH, not perform decoding of the retransmission PDSCH, set the HARQ-ACK information to NACK, or not feed back HARQ-ACK information.

[0364] Additionally, the control unit (1620) may not consider the above scheduling constraint (comparison of instantaneous data rate and maximum data rate) if certain conditions are satisfied. The operation of the terminal described above may be controlled by the control unit (1620), and specific details are omitted.

[0365] The storage unit (1630) can store at least one of the information transmitted and received through the transmission and reception unit (1610) and the information generated through the control unit (1620).

[0366] FIG. 17 is a drawing illustrating the structure of a base station according to one embodiment of the present disclosure.

[0367] Referring to FIG. 17, the base station may include a transceiver (1710), a control unit (1720), and a storage unit (1730). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

[0368] The transceiver (1710) can transmit and receive signals with other network entities. The transceiver (1710) can, for example, transmit configuration information from a base station to a terminal, and said configuration information may be transmitted via RRC signaling, MIB, or SIB. said configuration information may include information about BWP and information about mcs-Table. The transceiver (1710) can transmit DCI via a group common PDCCH or a group specific PDCCH. In addition, the transceiver (1710) can transmit data to the terminal. The transceiver (1710) can transmit new transmission data or retransmission data to the terminal.

[0369] The control unit (1720) can control the overall operation of the base station according to the embodiment proposed in the present invention. For example, the control unit (1720) can control the signal flow between each block to perform operations according to the flowchart described above. For example, the control unit (1720) can generate a DCI according to the embodiment of the present disclosure. The control unit (1720) can determine the DCI based on whether the data to be transmitted is for group communication (or whether the data is group common data or UE-specific data). Alternatively, the control unit (1720) can determine the type of the DCI based on whether the DCI to be transmitted is for group communication (or whether the DCI is a group common DCI or a UE-specific DCI). The control unit (1720) can determine the modulation order and target code rate of the data to be transmitted through the PDSCH scheduled by the DCI, and can determine an MCS index indicating the modulation order and target code rate. The above MCS index can be determined using different mcs-Tables depending on the type of DCI. And the control unit (1720) can transmit the DCI including the above MCS index to the terminal.

[0370] Additionally, the control unit (1720) can transmit the first DCI and the second DCI. If data transmitted from the first PDSCH is to be retransmitted from the second PDSCH, the NDI value for the same HARQ process number can be set identically and transmitted to the terminal regardless of the RNTI value used in the first DCI and the second DCI. Additionally, if the control unit (1720) intends to transmit data having the same TBS as the data transmitted from the first PDSCH, the value of the MCS index included in the second DCI can be set to be greater than or equal to a specific value. Additionally, if the control unit (1720) intends to allow data to be processed regardless of scheduling constraints, the time domain resource assignment information included in the DCI can be set so that it does not satisfy (or satisfies) a specific condition. The operation of the base station described above can be controlled by the control unit (1720), and specific details are omitted.

[0371] The storage unit (1730) can store at least one of the information transmitted and received through the transmission and reception unit (1710) and the information generated through the control unit (1720).

[0372] Accordingly, according to various embodiments of the present disclosure, a method performed by a terminal in a communication system comprises: receiving configuration information for a group common resource from a base station; receiving downlink control information (DCI) from the base station based on the configuration information; checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling a CRC (cyclic redundancy check) attached to the DCI; and, if the group common RNTI is used, determining a code rate and a modulation order based on information related to a group common MCS (modulation and coding scheme).

[0373] Additionally, according to various embodiments of the present disclosure, a method performed by a base station in a communication system comprises: transmitting configuration information for a group common resource to a terminal; transmitting downlink control information (DCI) to the terminal based on the configuration information; and transmitting data based on the DCI, wherein when a group common RNTI (radio network temporary identifier) ​​is used for scrambling a CRC (cyclic redundancy check) attached to the DCI, the modulation and coding scheme (MCS) index included in the DCI is determined based on information related to the group common MCS (modulation and coding scheme).

[0374] In addition, according to various embodiments of the present disclosure, a terminal in a communication system comprises: a transceiver; and a control unit connected to the transceiver, receiving configuration information for a group common resource from a base station, receiving downlink control information (DCI) from the base station based on the configuration information, checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling of a CRC (cyclic redundancy check) attached to the DCI, and if the group common RNTI is used, determining a code rate and a modulation order based on information related to a group common MCS (modulation and coding scheme).

[0375] In addition, according to various embodiments of the present disclosure, a base station in a communication system comprises: a transceiver; and a control unit connected to the transceiver, which transmits configuration information for a group common resource to a terminal, transmits downlink control information (DCI) to the terminal based on the configuration information, and transmits data based on the DCI, wherein when a group common RNTI (radio network temporary identifier) ​​is used for scrambling of a CRC (cyclic redundancy check) attached to the DCI, the modulation and coding scheme (MCS) index included in the DCI is determined based on information related to the group common MCS (modulation and coding scheme).

[0376] Meanwhile, the order of description in the drawings illustrating the method of the present invention does not necessarily correspond to the order of execution, and the order of execution may be changed or executed in parallel.

[0377] Alternatively, drawings describing the method of the present invention may omit some components and include only some components to the extent that the essence of the present invention is not compromised.

[0378] In addition, the method of the present invention may be implemented by combining some or all of the contents included in each embodiment within a scope that does not impair the essence of the invention.

Claims

Claim 1 A method performed by a terminal in a communication system, comprising: receiving configuration information for a group common resource from a base station; receiving downlink control information (DCI) from the base station based on the configuration information; checking whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling of a CRC (cyclic redundancy check) attached to the DCI; determining a code rate and modulation order based on a group common MCS (modulation and coding scheme) table if the group common RNTI is used; and determining a code rate and modulation order based on a terminal-specific MCS table if the group common RNTI is not used, wherein the configuration information comprises at least one of the group common MCS table or the terminal-specific MCS table, and the group common MCS table and the terminal-specific MCS table comprise information regarding a code rate and modulation order corresponding to an MCS index. Claim 2 A method according to claim 1, wherein the DCI is a first DCI, and when a second DCI is received, even if the RNTI associated with the first DCI and the second DCI is different, the NDI included in the second DCI is not toggled, the data received from the resource scheduled by the second DCI is retransmitted data, and when the MCS index included in the second DCI is greater than or equal to a specific value, the size of the data received from the resource scheduled by the second DCI is the same as the size of the data received from the resource scheduled by the first DCI, and when the number of symbols determined based on the time resource allocation information included in the second DCI does not satisfy a predetermined condition, and even when the instantaneous data rate is greater than the maximum data rate supported by the terminal, the data received from the resource scheduled by the second DCI is processed. Claim 3 A method performed by a base station in a communication system, comprising: transmitting configuration information for a group common resource to a terminal; transmitting downlink control information (DCI) to the terminal based on the configuration information; and transmitting data based on the DCI, wherein when a group common RNTI (radio network temporary identifier) ​​is used for scrambling of a CRC (cyclic redundancy check) attached to the DCI, an MCS (modulation and coding scheme) index included in the DCI is determined based on a group common MCS (modulation and coding scheme) table, and when the group common RNTI is not used, an MCS index included in the DCI is determined based on a terminal-specific MCS table, wherein the configuration information includes at least one of the group common MCS table or the terminal-specific MCS table, and the group common MCS table and the terminal-specific MCS table include information on a code rate and a modulation order corresponding to the MCS index. Claim 4 A method characterized in that, in paragraph 3, the DCI is a first DCI, and when a second DCI is transmitted, even if the RNTI associated with the first DCI and the second DCI is different, the NDI included in the second DCI is not toggled, the data transmitted from the resource scheduled by the second DCI is retransmitted data, and when the MCS index included in the second DCI is greater than or equal to a specific value, the size of the data transmitted from the resource scheduled by the second DCI is the same as the size of the data transmitted from the resource scheduled by the first DCI, and when the number of symbols determined based on the time resource allocation information included in the second DCI does not satisfy a predetermined condition, and even when the instantaneous data rate is greater than the maximum data rate supported by the terminal, the data transmitted from the resource scheduled by the second DCI is processed. Claim 5 A terminal in a communication system comprises: a transceiver; and a control unit connected to the transceiver; wherein the control unit receives configuration information for a group common resource from a base station, receives downlink control information (DCI) from the base station based on the configuration information, determines whether a group common RNTI (radio network temporary identifier) ​​is used in scrambling of a CRC (cyclic redundancy check) attached to the DCI, determines a code rate and modulation order based on a group common MCS (modulation and coding scheme) table if the group common RNTI is used, and determines a code rate and modulation order based on a terminal-specific MCS table if the group common RNTI is not used, wherein the configuration information includes at least one of the group common MCS table or the terminal-specific MCS table, and the group common MCS table and the terminal-specific MCS table include information regarding a code rate and modulation order corresponding to an MCS index. Claim 6 A terminal characterized in that, in claim 5, the DCI is a first DCI, and when a second DCI is received, even if the RNTI associated with the first DCI and the second DCI is different, the NDI included in the second DCI is not toggled, the data received from the resource scheduled by the second DCI is retransmitted data, and when the MCS index included in the second DCI is greater than or equal to a specific value, the size of the data received from the resource scheduled by the second DCI is the same as the size of the data received from the resource scheduled by the first DCI, and when the number of symbols determined based on the time resource allocation information included in the second DCI does not satisfy a predetermined condition, and even when the instantaneous data rate is greater than the maximum data rate supported by the terminal, the data received from the resource scheduled by the second DCI is processed. Claim 7 A base station in a communication system comprises: a transceiver; and a control unit connected to the transceiver; wherein the control unit transmits configuration information for a group common resource to a terminal, transmits downlink control information (DCI) to the terminal based on the configuration information, and transmits data based on the DCI; wherein, when a group common RNTI (radio network temporary identifier) ​​is used for scrambling of a CRC (cyclic redundancy check) attached to the DCI, an MCS (modulation and coding scheme) index included in the DCI is determined based on a group common MCS (modulation and coding scheme) table, and when the group common RNTI is not used, an MCS index included in the DCI is determined based on a terminal-specific MCS table; wherein the configuration information includes at least one of the group common MCS table or the terminal-specific MCS table, and the group common MCS table and the terminal-specific MCS table include information regarding a code rate and a modulation order corresponding to the MCS index. Claim 8 A base station according to claim 7, wherein the DCI is a first DCI, and when a second DCI is transmitted, even if the RNTI associated with the first DCI and the second DCI is different, the NDI included in the second DCI is not toggled, the data transmitted from the resource scheduled by the second DCI is retransmitted data, and when the MCS index included in the second DCI is greater than or equal to a specific value, the size of the data transmitted from the resource scheduled by the second DCI is the same as the size of the data transmitted from the resource scheduled by the first DCI, and when the number of symbols determined based on the time resource allocation information included in the second DCI does not satisfy a predetermined condition, and even when the instantaneous data rate is greater than the maximum data rate supported by the terminal, the data transmitted from the resource scheduled by the second DCI is processed. Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 delete Claim 16 delete Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete

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