Method and apparatus for transmitting data in a wireless cellular communication system

Abstract

The present invention relates to communication technologies and systems for communication technologies. The present invention can be applied to intelligent services (such as smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety-related services, etc.) based on 5G communication technology and IoT-related technologies. The present invention provides a method performed by a terminal in a wireless communication system, including: receiving information about the number of codeblock groups for each transport block TB from a base station, where each codeblock group includes at least one codeblock; receiving the TB and control information for scheduling the TB from the base station; identifying the codeblock group of the TB based on the number of codeblocks of the TB and the information, the number of codeblocks of the TB being determined based on the control information; decoding the TB based on the identified codeblock group; and sending hybrid automatic repeat request HARQ feedback information to the base station based on the decoding result.

Description

[0001] This case is a divisional application of a patent application for invention with the application date of October 30, 2017, application number 201780068025.7, and invention title "Method and apparatus for transmitting data in a wireless cellular communication system". Technical Field

[0002] The present disclosure relates to a wireless communication system, and more particularly to a transmission method and apparatus capable of decomposing a transport block into one or more sub-transport blocks and decomposing each sub-transport block into one or more code blocks, and encoding and transmitting one or more code blocks with one or more channel codes. Background Art

[0003] In order to meet the increasing demand for wireless data traffic since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "Beyond 4G Networks" or "Post-LTE (Long Term Evolution) systems". The implementation of 5G communication systems in higher frequency (mmWave) bands (e.g., 60 GHz band) is being considered to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technologies are being discussed for 5G communication systems. In addition, in 5G communication systems, developments for system network improvements are ongoing based on advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multi-points (CoMP), receiver interference cancellation, etc. In 5G systems, hybrid FSK (Frequency Shift Keying) and QAM (Quadrature Amplitude Modulation) modulation (Hybrid FSK and QAM Modulation, FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coding modulation (ACM), as well as filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies.

[0004] The Internet is a human - centric connectivity network where humans generate and consume information, and is now evolving into the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE), as a combination of IoT technology and big - data processing technology through connection with cloud servers, has emerged. Since technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology", and "security technology" are required for IoT implementation, research has recently been conducted on sensor networks, Machine - to - Machine (M2M) communication, Machine - Type Communication (MTC), etc. Such an IoT environment can provide intelligent Internet technology services, which create new value for human life by collecting and analyzing data generated among connected things. Through the integration and combination between existing Information Technology (IT) and various industrial applications, IoT can be applied to multiple fields including smart home, smart building, smart city, smart car or connected vehicle, smart grid, healthcare, smart appliances, and advanced medical services.

[0005] In line with these developments, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, Machine - Type Communication (MTC), and Machine - to - Machine (M2M) communication can be implemented by beamforming, MIMO, and array antennas. Cloud Radio Access Network (RAN), as an application of the above - mentioned big - data processing technology, can also be considered as an example of the integration between 5G technology and IoT technology.

[0006] Meanwhile, data is sent by transport blocks (TBs) in a wireless communication system (especially a traditional LTE system). A TB is decomposed into multiple code blocks (CBs), and channel coding is performed on the CBs. Retransmission following the initial transmission is performed on the TB, which leads to the problem that a decoding failure on one CB causes the retransmission of the entire TB. SUMMARY OF THE INVENTION

[0007] TECHNICAL PROBLEM

[0008] The present invention aims to define a sub - transport block (sub - TB) for the case of re - transmitting a part that requires a TB. The present invention also provides a method for allowing a receiver to determine whether a transmission is successful or not by adding a cyclic redundancy check (CRC) to a TB, a sub - TB, and a CB, and a method for a base station to configure the CRC length. The sub - TB defined in the present invention is a virtual concept, and it may be possible to only consider the actually added CRC for each virtual sub - TB.

[0009] Technical solution

[0010] According to an aspect of the present invention, a method for a terminal to transmit data in a wireless communication system includes: receiving information about a sub - transport block from a base station, determining a sub - transport block based on the information about the sub - transport block and the number of code blocks that constitute a scheduled transport block, and transmitting data to the base station via the sub - transport block, where the sub - transport block is a bundle of at least one code block.

[0011] Preferably, determining the sub - transport block includes: decomposing a scheduled transport block into at least one code block and grouping the at least one code block into sub - transport blocks based on the information about the sub - transport block and the number of code blocks that constitute the scheduled transport block.

[0012] Preferably, the information about the sub - transport block includes the number of sub - transport blocks that constitute a scheduled transport block, and determining the sub - transport block includes determining the sub - transport block based on the number of sub - transport blocks and the number of code blocks.

[0013] Preferably, if the number of code blocks is equal to or less than the number of sub - transport blocks, the sub - transport block is determined based on the number of code blocks.

[0014] Preferably, if the number of code blocks is greater than the number of sub - transport blocks, the sub - transport block is determined based on the number of sub - transport blocks.

[0015] Preferably, the sub - transport block is determined based on at least one of a transmission time interval (TTI) of the data, the size of a scheduled transport block, and control information received from the base station.

[0016] According to another aspect of the present invention, a method for a base station to receive data in a wireless communication system includes: sending information about a sub - transport block to a terminal, and receiving data from the terminal via at least one sub - transport block determined based on the information about the sub - transport block and the number of code blocks that constitute a scheduled transport block, where the sub - transport block is a bundle of at least one code block.

[0017] Preferably, the information about the sub - transport block is sent to the terminal via higher - layer signaling.

[0018] According to another aspect of the present invention, a terminal of a wireless communication system includes: a transceiver configured to transmit and receive signals; and a controller configured to control the transceiver to receive information about sub - transport blocks from a base station, determine sub - transport blocks based on the information about the sub - transport blocks and the number of code blocks constituting a scheduled transport block, and control the transceiver to transmit data to the base station via the sub - transport blocks, where the sub - transport blocks are bundles of at least one code block.

[0019] Preferably, the controller is configured to control to decompose a scheduled transport block into at least one code block and group the at least one code block into sub - transport blocks based on the information about the sub - transport blocks and the number of code blocks constituting the scheduled transport block.

[0020] Preferably, the information about the sub - transport blocks includes the number of sub - transport blocks constituting the scheduled transport block, and the controller is configured to determine the sub - transport blocks based on the number of sub - transport blocks and the number of code blocks.

[0021] Preferably, the controller is configured to, if the number of code blocks is equal to or less than the number of sub - transport blocks, determine the sub - transport blocks based on the number of code blocks.

[0022] Preferably, the controller is configured to, if the number of code blocks is greater than the number of sub - transport blocks, determine the sub - transport blocks based on the number of sub - transport blocks.

[0023] Preferably, the controller is configured to determine the sub - transport blocks based on at least one of a transmission time interval (TTI) of data, a size of a scheduled transport block, and control information received from the base station.

[0024] According to yet another aspect of the present invention, a base station of a wireless communication system includes: a transceiver configured to transmit and receive signals; and a controller configured to control the transceiver to send information about sub - transport blocks to a terminal and receive data from the terminal via at least one sub - transport block determined based on the information about the sub - transport blocks and the number of code blocks constituting a scheduled transport block, where the sub - transport blocks are bundles of at least one code block.

[0025] According to yet another aspect of the present invention, a method performed by a terminal in a wireless communication system is provided. The method includes: receiving, from a base station, information about the number of code - block groups of each transport block TB, where each code - block group includes at least one code block; receiving the TB and control information for scheduling the TB from the base station; identifying the code - block groups of the TB based on the number of code blocks of the TB and the information, the number of code blocks of the TB being determined based on the control information; decoding the TB based on the identified code - block groups; and sending hybrid automatic repeat request (HARQ) feedback information to the base station based on the decoding result.

[0026] According to another aspect of the present invention, there is provided a method performed by a base station in a wireless communication system, the method comprising: sending information about the number of code block groups for each transport block TB to a terminal, where each code block group includes at least one code block; identifying the code block groups of the TB based on the number of code blocks of the TB and the information; sending the identified code block groups of the TB and control information for scheduling the TB to the terminal; and receiving hybrid automatic repeat request HARQ feedback information for the identified code block groups from the terminal. According to another aspect of the present invention, there is provided a terminal in a wireless communication system, the terminal comprising: a transceiver; and a controller configured to: control the transceiver to receive information about the number of code block groups for each transport block TB from a base station, where each code block group includes at least one code block, control the transceiver to receive the TB and control information for scheduling the TB from the base station, identify the code block groups of the TB according to the number of code blocks of the TB and the information, the number of code blocks of the TB being determined according to the control information, decode the TB according to the identified code block groups, and control the transceiver to send hybrid automatic repeat request HARQ feedback information to the base station based on the decoding result.

[0028] According to another aspect of the present invention, there is provided a base station in a wireless communication system, the base station comprising: a transceiver; and a controller configured to: control the transceiver to send information about the number of code block groups for each transport block TB to a terminal, where each code block group includes at least one code block, identify the code block groups of the TB according to the number of code blocks of the TB and the information, control the transceiver to send the identified code block groups of the TB and control information for scheduling the TB to the terminal, and control the transceiver to receive hybrid automatic repeat request HARQ feedback information for the identified code block groups from the terminal.

[0029] Advantages of the Invention

[0030] The present invention is advantageous in promoting the transmission operations of the base station and the terminal and reducing unnecessary data transmissions by introducing the concept of sub-TB to allow retransmission of parts of the TB. Brief Description of the Drawings

[0031] Figure 1a is a diagram showing the basic time-frequency resource structure for transmitting downlink data or a control channel in an LTE system;

[0032] Figure 1b is a diagram showing the basic time-frequency resource structure for transmitting uplink data or a control channel in an LTE-A (LTE-Advanced) system;

[0033] Figure 1c It is a diagram showing frequency - time resources allocated for eMBB (enhanced mobile broadband), URLLC (ultra - reliable and low - latency communication), and mMTC (massive machine type communication) data transmission in a communication system;

[0034] Figure 1d It is a diagram showing frequency - time resources allocated for eMBB, URLLC, and mMTC data transmission in a communication system;

[0035] Figure 1e It is a diagram showing the process of decomposing a transport block into multiple code blocks and adding CRC to the code blocks according to an embodiment of the present invention;

[0036] Figure 1f It is a diagram showing an outer - code - based coding structure according to an embodiment of the present invention;

[0037] Figure 1g It is a diagram showing a channel coding process of applying or not applying an outer code according to another embodiment of the present invention;

[0038] Figure 1h It is a diagram showing a method for configuring sub - TB and CB and adding CRC to sub - TB and CB according to an embodiment of the present invention; [[ID=SS]]

[0039] Figure 1i It is a diagram showing a method for configuring sub - TB and CB and adding CRC to sub - TB and CB according to another embodiment of the present invention;

[0040] Figure 1j It is a diagram showing a method for configuring sub - TB and CB and adding CRC to sub - TB and CB according to another embodiment of the present invention;

[0041] Figure 1k It is a diagram showing a method for configuring sub - TB and CB and adding CRC to sub - TB and CB according to another embodiment of the present invention;

[0042] Figure 1l It is a flowchart showing the process of a transmitter according to Embodiments 1 - 2 of the present invention;

[0043] Figure 1m It is a flowchart showing the process of a receiver according to Embodiments 1 - 2 of the present invention;

[0044] Figure 1n is a flowchart of a transmitter according to Embodiment 2 of the present invention;

[0045] Figure 1o is a flowchart of a receiver according to Embodiment 2 of the present invention;

[0046] Figure 1p is a flowchart showing a process of a receiver according to Embodiment 4 of the present invention;

[0047] Figure 1q is a flowchart showing a process of a transmitter according to Embodiment 4 of the present invention;

[0048] Figure 1r is a block diagram showing a configuration of a UE according to an embodiment of the present invention; and

[0049] Figure 1s is a block diagram showing a configuration of a base station according to an embodiment of the present invention. Detailed Description of the Invention

[0050] Exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings. Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present invention. In addition, the following terms are defined in consideration of the functionality in the present invention, and they may vary according to the intention, use, etc. of the user or operator. Therefore, the definitions should be made based on the overall content of this specification.

[0051] Advantages and features of the present invention and methods for implementing the present invention can be more easily understood by referring to the following detailed description of the exemplary embodiments and the accompanying drawings. However, the present invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. On the contrary, these exemplary embodiments are provided so that the present invention will be thorough and complete, and the concept of the present invention will be fully conveyed to those skilled in the art, and the present invention will be defined only by the appended claims. Throughout the specification, the same reference numerals refer to the same elements.

[0052] In order to meet the growing demand for wireless data traffic since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-LTE systems". To achieve higher data rates, the implementation of 5G communication systems in higher frequency (mmWave) bands (such as the 60 GHz band) is being considered. To reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technologies are being discussed for 5G communication systems. In addition, in 5G communication systems, developments for system network improvements are being carried out based on advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multi-point (CoMP), receiver interference cancellation, etc. In 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superimposed coding (SWSC) as advanced coding modulation (ACM), as well as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies, have been developed.

[0053] The Internet is a human-centric connectivity network where humans generate and consume information, and is now evolving into the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE) has emerged as a combination of IoT technologies and big data processing technologies through connections to cloud servers. Since technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology", and "security technology" have been required for IoT implementation, recent research has been conducted on sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. Such an IoT environment can provide intelligent Internet technology services that create new value for human life by collecting and analyzing data generated among connected things. Through the integration and combination of existing information technology (IT) and various industrial applications, IoT can be applied to multiple fields including smart homes, smart buildings, smart cities, smart cars or connected vehicles, smart grids, healthcare, smart appliances, and advanced medical services.

[0054] In line with these developments, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communication (MTC), and machine-to-machine (M2M) communication can be implemented through beamforming, MIMO, and array antennas. Cloud radio access network (RAN) as an application of the above big data processing technology can also be considered as an example of the convergence between 5G technology and IoT technology.

[0055] Meanwhile, 5G new radio access technology (NR) is designed to allow various types of services to be freely multiplexed onto time and frequency resources and to dynamically or freely allocate waveforms / digitals and reference signals to meet service-specific requirements. For wireless communication where channel quality and interference measurement are crucial for providing the best service to terminals, accurate channel state measurement is inevitable. Different from 4G communication where channel and interference characteristics rarely vary with frequency resources, 5G communication is characterized by the fact that channel and interference characteristics vary significantly with services, which makes it necessary to support a subset of frequency resource groups (FRGs) for their individual measurements. Meanwhile, the services supported in the NR system are classified into three categories: enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable and low-latency communication (URLLC). The eMBB service is characterized by high-capacity and high-mobility communication, the mMTC service is characterized by low power consumption and large-scale connection, and URLLC is characterized by ultra-high reliability and low latency. Requirements may vary depending on the type of service provided to the terminal.

[0056] To enable a communication system to provide various types of services to users, methods and apparatuses for multiplexing different services onto the same time period to meet service-specific requirements are needed.

[0057] Exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings.

[0058] Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present invention. This is intended to omit unnecessary descriptions to clarify the subject matter of the present invention.

[0059] For the same reason, some elements are exaggerated, omitted, or simplified in the drawings, and in practice, the elements may have different sizes and / or shapes from those shown in the drawings. The same reference numerals are used throughout the drawings to refer to the same or similar parts.

[0060] Advantages and features of the present invention and a method of realizing the present invention can be more easily understood by referring to the following detailed description of exemplary embodiments and the accompanying drawings. However, the present invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the present invention to those skilled in the art. The present invention will only be defined by the appended claims. Throughout the specification, the same reference numerals refer to the same elements.

[0061] It will be understood that each block of the flowchart(s) and / or block diagram(s), and combinations of blocks in the flowchart(s) and / or block diagram(s), can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart(s) and / or block diagram(s). These computer program instructions may also be stored in a non-transitory computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the non-transitory computer readable memory produce an article of manufacture including instruction means embodying the functions / acts specified in the flowchart(s) and / or block diagram(s). The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions / acts specified in the flowchart(s) and / or block diagram(s).

[0062] In addition, each block diagram may show a module, segment, or portion of code that includes at least one or more executable instructions for performing a (multiple) particular logical function. In addition, it should be noted that the functions of the blocks may be executed in a different order in several modifications. For example, two consecutive blocks may be executed substantially simultaneously, or may be executed in the reverse order according to their functions.

[0063] According to various embodiments of the present invention, the term "module" means, but is not limited to, a software or hardware component that performs certain tasks, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). A module can be advantageously configured to reside on an addressable storage medium and configured to run on one or more processors. Thus, by way of example, a module can include components (such as software components, object-oriented software components, class components, and task components), processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality of components and modules can be combined into fewer components and modules, or further separated into more components and modules. Additionally, components and modules can be implemented such that they run on one or more CPUs in a device or a security multimedia card. A module can include one or more processors.

[0064] Mobile communication systems have evolved into high-speed, high-quality packet data communication systems capable of providing data and multimedia services beyond early voice-oriented services, such as High Speed Packet Access (HSPA), LTE (or evolved universal terrestrial radio access (E-UTRA)), and advanced LTE (LTE-A) defined in the 3rd Generation Partnership Project (3GPP), High Rate Packet Data (HRPD) defined in the 3rd Generation Partnership Project-2 (3GPP2), Ultra Mobile Broadband (UMB), and 802.16e defined in the IEEE. At the same time, 5G or NR standardization is in progress for the 5G wireless communication system. rd Generation Partnership Project, 3GPP), High Rate Packet Data (HRPD) defined in the 3rd Generation Partnership Project-2 (3GPP2), Ultra Mobile Broadband (UMB), and 802.16e defined in the IEEE. At the same time, 5G or NR standardization is in progress for the 5G wireless communication system.

[0065] As one of the representative broadband wireless communication systems, the LTE system uses orthogonal frequency division multiplexing (OFDM) in the downlink (DL) and single carrier frequency division multiple access (SC-FDMA) in the uplink (UL). The term "uplink" refers to the radio link for sending data or control signals from a terminal, interchangeably called user equipment (UE) and mobile station (MS), to a base station (BS), interchangeably called evolved node B (eNB). The term "downlink" refers to the radio link for sending data or control signals from the base station to the terminal. The characteristic of this multiple access scheme is to allocate time-frequency resources for sending user-specific data and control information without overlapping with each other, that is, to maintain orthogonality, so as to distinguish among user-specific data and control information.

[0066] When a decoding failure occurs in the initial data transmission, the LTE system applies the Hybrid Automatic Repeat Request (HARQ) scheme for physical layer retransmission. The HARQ scheme is designed to operate in such a way that when the receiver fails to decode the data, it sends a negative acknowledgement (NACK) indicating the decoding failure to the transmitter, so that the transmitter can retransmit the corresponding data at the physical layer. The receiver combines the retransmitted data with the data that failed to be decoded to improve the data reception performance. The HARQ scheme can also be designed to operate in such a way that when the receiver successfully decodes the data, it transmits an acknowledgement (ACK) indicating successful decoding to the transmitter, so that the transmitter can send new data.

[0067] Figure 1a is a diagram showing the basic time-frequency resource structure for transmitting downlink data or control channels in the LTE system.

[0068] In Figure 1a it, the horizontal axis represents time, and the vertical axis represents frequency. The smallest transmission unit in the time domain is the OFDM symbol, and N symbOne OFDM symbol 1a - 02 forms a time slot 1a - 06, and 2 time slots form a sub - frame 1a - 05. Each time slot spans 0.5 milliseconds, and each sub - frame spans 1.0 millisecond. A radio frame 1a - 14 is a time unit composed of 10 sub - frames. In the frequency domain, the smallest transmission unit is a sub - carrier, and the total system transmission bandwidth is composed of N BW sub - carriers 1a - 04.

[0069] In the time - frequency resource structure, the basic resource unit is a resource element (RE) 1a - 12 indicated by the OFDM symbol index and the sub - carrier index. A resource block (RB) (or physical resource block (PRB)) 1a - 08 is defined by N symb consecutive OFDM symbols 1a - 02 in the time domain and N RB consecutive sub - carriers 1a - 10 in the frequency domain.

[0070] That is to say, one RB 1a - 08 is composed of N symb x N RB REs 1a - 12. Typically, an RB is the smallest data transmission unit. In the LTE system, N symb = 7, N RB = 12, and N BW and N RB are proportional to the system transmission bandwidth; non - LTE systems can use different values.

[0071] The data rate increases proportionally with the number of RBs scheduled to the terminal. For the LTE system, 6 transmission bandwidths are defined. In the case of an FDD (frequency division duplex) system where the downlink and uplink are separated in frequency, the downlink transmission bandwidth and the uplink transmission bandwidth can be different from each other.

[0072] Compared with the system transmission bandwidth, the channel bandwidth represents the RF (radio frequency) bandwidth. Table 1a shows the relationship between the system transmission bandwidth and the channel bandwidth defined in the LTE standard. For example, an LTE system with a 10 MHz channel bandwidth uses a transmission bandwidth of 50 RBs.

[0073]

Table 1

[0074]

[0075] Downlink control information is sent in N OFDM symbols at the start of a subframe. Typically, N = {1, 2, 3}. Thus, the value of N varies at each subframe according to the amount of control information to be sent. The control information includes a control channel transmission period indicator for indicating the number of OFDM symbols used to convey the control information, scheduling information for downlink or uplink data transmission, and a HARQ ACK / NACK signal.

[0076] In an LTE system, downlink or uplink data scheduling information is sent from a base station to a terminal using Downlink Control Information (DCI). DCI is classified into different DCI formats depending on the purpose, such as indicating a UL grant for UL data scheduling or a DL grant for DL data scheduling, indicating the use of small-sized control information, indicating whether spatial multiplexing based on multiple antennas is applied, and indicating the use of power control. For example, DCI format 1 for DL grant is configured to include at least the following information.

[0077] - Resource allocation type 0 / 1 flag: The resource allocation type 0 / 1 flag indicates whether the resource allocation scheme is type 0 or type 1. Type 0 is used to allocate resources in units of Resource Block Groups (RBGs) by applying a bitmap scheme. In an LTE system, the basic unit of scheduling can be a resource block (RB) expressed by time-frequency domain resources, and an RBG can include multiple RBs and can be the basic unit of scheduling in a type 0 scheme. Type 1 is used to allocate specific RBs within an RBG.

[0078] - Resource block assignment: The resource block assignment indicates the RBs allocated for data transmission. The resources can be determined depending on the system bandwidth and the resource allocation scheme.

[0079] - Modulation and coding scheme (MCS): The MCS indicates the modulation scheme for data transmission and the size of the transport block to be transmitted.

[0080] - HARQ process number: The HARQ process number indicates the process number of HARQ.

[0081] - New data indicator: The new data indicator indicates whether the HARQ transmission is an initial transmission or a retransmission.

[0082] - Redundancy version: The redundancy version indicates the redundancy version of HARQ.

[0083] - TPC (Transmit Power Control) commands for PUCCH: TPC commands for the Physical Uplink Control Channel (PUCCH) indicate power control commands for the PUCCH as an uplink control channel.

[0084] DCI can be transmitted on the Physical Downlink Control Channel (PDCCH) or Enhanced PDCCH (EPDCCH) after undergoing channel coding and modulation processes. In the following descriptions, PDCCH transmission / reception can be understood as DCI transmission / reception on the PDCCH. Other channels can be understood in a similar manner.

[0085] Typically, DCI is configured and transmitted by each individual PDCCH after being channel-coded after adding CRC (Cyclic Redundancy Check), and the CRC is separately scrambled with a specific RNTI (Radio Network Temporary Identifier) (or terminal identifier) of each terminal. In the time domain, the PDCCH can be mapped and transmitted during the control channel transmission period. The frequency-domain mapping position of the PDCCH can be determined by the ID of each terminal, and it can be extended across the entire system transmission band.

[0086] Downlink data can be transmitted on the Physical Downlink Shared Channel (PDSCH) which is a physical channel for downlink data transmission. The PDSCH can be transmitted after the control channel transmission period, and scheduling information such as the detailed mapping position in the frequency domain and modulation scheme can be indicated by DCI transmitted on the PDCCH.

[0087] Using MCS as part of the control information constituting DCI, the base station notifies the terminal of the modulation scheme applied to the PDSCH to be transmitted and the size of the data to be transmitted (e.g., Transport Block Size (TBS)). In one embodiment, MCS has a bit width of 5 or less than or greater than 5. The TBS corresponds to the size given before applying channel coding for error correction to the data (e.g., Transport Block (TB)) to be transmitted by the base station.

[0088] Modulation schemes supported by the LTE system can include Quadrature Phase Shift Keying (QPSK), 16-Quadrature Amplitude Modulation (QAM), and 64QAM, and they have modulation orders (Qm) of 2, 4, and 6 respectively. That is, QPSK modulates and transmits 2 bits per symbol, 16QAM transmits 4 bits per symbol, and 64QAM transmits 6 bits per symbol. Depending on the system, 256QAM or higher-order modulation may also be used.

[0089] Figure 1b FIG. is a diagram showing the basic time-frequency resource structure for transmitting uplink data or a control channel in the LTE-A system.

[0090] In Figure 1b , the horizontal axis represents time, and the vertical axis represents frequency. The smallest transmission unit in the time domain is the SC-FDMA symbol, and N symb UL SC-FDMA symbols 1b-02 form a time slot 1b-06. Two time slots form a subframe 1b-05. The smallest transmission unit in the frequency domain is the subcarrier, and the overall system transmission bandwidth is composed of N BW subcarriers 1b-04. N BW can be proportional to the system transmission bandwidth.

[0091] In the time-frequency domain, the basic resource unit is RE 1b-12, and each RE is defined by an SC-FDMA symbol index and a subcarrier index. A resource block (RB) pair 1b-08 is defined by N symb UL consecutive SC-FDMA symbols in the time domain and N sc RB consecutive subcarriers in the frequency domain. Therefore, one RB is composed of N symb UL x N sc RB REs. Typically, the smallest data or control information transmission unit is the RB. The Physical Uplink Control Channel (PUCCH) is mapped to the frequency region corresponding to one RB and is transmitted during the time period of one subframe.

[0092] The LTE standard defines the relationship between a PDSCH or PDCCH / EPDCCH carrying a semi-persistent scheduling (SPS) release and a PUCCH or physical uplink shared channel (PUSCH) carrying HARQ ACK / NACK corresponding to the PDSCH, PDCCH, or EPDCCH. For example, in an LTE system operating in FDD mode, the HARQ ACK / NACK corresponding to a PDSCH or PDCCH or EPDCCH carrying an SPS release and transmitted in the (n - 4)th subframe is carried in the PUCCH or PUSCH transmitted in the nth subframe.

[0093] The LTE system employs an asynchronous HARQ scheme for DL HARQ. That is, if the eNB receives a HARQ NACK from the UE for the initially transmitted data, it can freely determine the retransmission timing through a scheduling operation. If the UE fails to decode the received data, it stores the incorrect initial data and combines the buffered data with the retransmitted data.

[0094] If the UE receives a PDSCH carrying DL data transmitted by the eNB in the nth subframe, it sends UL control information including the HARQ ACK / NACK corresponding to the DL data to the eNB in the (n + k)th subframe through the PUCCH or PUSCH. Here, k is determined differently depending on the duplex mode (i.e., FDD or time division duplex (TDD)) and the subframe configuration used by the LTE system. For example, in an FDD LTE system, k is fixed at 4. Meanwhile, k can vary according to the subframe configuration and subframe index in a TDD LTE system.

[0095] The LTE system uses a synchronous HARQ scheme with a fixed data transmission timing for UL transmission different from DL HARQ. That is, the UL-DL timing relationship between a PUSCH and a PDCCH followed by a PUSCH and a physical hybrid indicator channel (PHICH) carrying the DL HARQ ACK / NACK corresponding to the PUSCH is fixed according to the following rules.

[0096] If the UE receives a PDCCH carrying UL scheduling control information or a PHICH carrying DL HARQ ACK / NACK from the eNB at the n-th subframe, it transmits UL data via the PUSCH at the (n + k)-th subframe based on the control information. Here, k is determined differently depending on the duplex mode used, i.e., FDD or TDD and its configuration. For example, in an FDD LTE system, k is fixed at 4. Meanwhile, k can vary according to the subframe configuration and subframe index in a TDD LTE system.

[0097] In an FDD LTE system, the eNB transmits UL grants or DL control signals and data to the UE at the n-th subframe, and the UE receives UL grants or DL control signals and data at the n-th subframe. If the UE receives a UL grant at the n-th subframe, it transmits uplink data at the (n + 4)-th subframe.

[0098] If the UE receives DL control signals and data at the n-th subframe, it transmits the HARQ ACK / NACK corresponding to the DL data at the (n + 4)-th subframe. In this case, the period given for the UE to prepare for UL data transmission scheduled via a UL grant or for the transmission of HARQ ACK / NACK corresponding to DL data becomes 3 ms, and 3 ms is equal to the duration of three subframes.

[0099] The UE receives a PHICH carrying DL HARQ ACK / NACK from the eNB at the i-th subframe and receives the DL HARQ ACK / NACK corresponding to the PUSCH transmitted by the UE at the (i + k)-th subframe. Here, k is determined differently depending on the duplex mode (i.e., FDD or TDD) and its configuration in the use of the LTE system. For example, in an FDD LTE system, k is fixed at 4. Meanwhile, k can vary according to the subframe configuration and subframe index in a TDD LTE system.

[0100] Figure 1c and Figure 1d are diagrams showing the frequency-time resources allocated for transmitting data for eMBB, URLLC, and mMTC services considered in a 5G or NR system.

[0101] Figure 1c and Figure 1d show how to allocate frequency and time resources for information transmission in the system.

[0102] In Figure 1cIn it, eMBB, URLLC, and mMTC data are mapped across the entire system frequency band 1c-00. If URLLC data 1c-03, 1c-05, and 1c-07 are generated to be transmitted in a specific frequency band during the transmission of eMBB data 1c-01 and mMTC data 1c-09, then parts of the eMBB data 1c-01 and mMTC data 1c-09 can be punctured so that the URLLC data 1c-03, 1c-05, and 1c-07 are inserted.

[0103] Since the URLLC service is latency-sensitive among the foregoing services, the URLLC data 1c-03, 1c-05, and 1c-07 can occupy parts of the resources allocated for the eMBB data 1c-01. In the case of transmitting URLLC data on the resources allocated for eMBB data, the eMBB data may not be transmitted on the overlapping frequency-time resources, which can reduce the eMBB data transmission throughput. That is to say, in the above case, the resource allocation for URLLC data transmission can cause the eMBB data transmission to fail.

[0104] In Figure 1d it, the system frequency band 1d-00 is divided into sub-bands 1d-02, 1d-04, and 1d-06 for data transmission of different services. The sub-band configuration information can be pre-configured and sent from the base station to the terminal.

[0105] It may also be possible to share the sub-band configuration information for the base station or network node to provide the corresponding service without separately sending the sub-band configuration information to the terminal. In Figure 1d it, the sub-bands 1d-02, 1d-04, and 1d-06 are respectively allocated for eMBB 1d-08 data transmission, URLLC 1d-10, 1d-12, 1d-14 data transmission, and mMTC 1d-16 data transmission.

[0106] Throughout the entire embodiment, the transmission time interval (TTI) for URLLC transmission can be shorter than the TTI for eMBB or mMTC transmission. The acknowledgment corresponding to the URLLC data can be sent faster than the acknowledgment corresponding to the eMBB or mMTC data, resulting in low-latency information transmission / reception.

[0107] Figure 1e is a diagram showing the process of decomposing a transport block into multiple code blocks and adding a CRC to the code blocks.

[0108] Refer to Figure 1e, a cyclic redundancy check (CRC) 1e-03 can be added at the start or end of a transport block (TB) 1e-01 to be transmitted on the uplink or downlink. The CRC can have a fixed length of 16 bits or 24 bits or a variable length that varies with channel conditions, and can be used to determine whether channel coding is successful.

[0109] The block including the TB 1e-01 and the CRC 1e-03 can be decomposed into multiple code blocks (CBs) 1e-07, 1e-09, 1e-11, and 1e-13, as indicated by reference numeral 1e-05. Each CB preferably has a predetermined maximum size, and in this case, the last CB 1e-13 can be smaller in size than the other code blocks. It is possible to add 0, a random value, or 1 to the last CB to make the last CB equal in length to the other CBs.

[0110] It is possible to add CRCs 1e-17, 11e-19, 1e-21, and 1e-23 to the respective CBs. The CRC can have a fixed length such as 16 bits, 24 bits, etc., and can be used to determine whether channel coding is successful.

[0111] However, depending on the type of channel code to be applied to the CBs, adding the CRC 1e-03 to the TB and adding the CRCs 1e-17, 11e-19, 1e-21, and 1e-23 to the respective CBs can be omitted. For example, in the case of applying a low-density parity-check (LDPC) code instead of a turbo code, adding the CRCs 1e-17, 1e-19, 1e-21, and 1e-23 to the respective CBs can be omitted. However, even when applying an LDPC code, the CRCs 1e-17, 11e-19, 1e-21, and 1e-23 can be added to the CBs. Even in the case of using a polar code, it is possible to omit adding any CRCs.

[0112] Figure 1f is a diagram showing a transmission method based on an outer code, and Figure 1g is a diagram showing the structure of a communication system based on an outer code.

[0113] Refer to Figure 1f and Figure 1g for a description of a method of transmitting a signal using an outer code.

[0114] In Figure 1fIn it, the TB is decomposed into multiple CBs, and the bits or symbols 1f-04 at the equal bit positions in the multiple CBs are encoded with a second channel code to generate parity bits or symbols 1f-06, as indicated by reference numeral 1f-02. Next, CRCs 1f-08 and 1f-10 can be added to the CB and the parity-check CB generated by encoding with the second channel code, respectively. Depending on the type of the channel code, it may or may not be possible to add CRCs. For example, if a turbo code is used as the first channel code, CRCs 1f-08 and 1f-10 are added and then the CB and the parity-check CB can be encoded with the first channel code.

[0115] In the case of using an outer code, the data to be transmitted passes through a second channel encoding encoder 1g-09. Examples of channels encoded by the second channel encoding can include Reed-Solomon codes, BCH codes, Raptor codes, and parity-bit generation codes. The bits or symbols passing through the second channel encoding encoder 1g-09 pass through a first channel encoding encoder 1g-11. Examples of channel codes for the first channel encoding can include convolutional codes, LDPC codes, turbo codes, and polar codes.

[0116] If the receiver receives the channel-encoded symbols over the channel 1g-13, the receiver can process the received signals in sequential order by means of a first channel decoding decoder 1g-15 and a second channel decoding decoder 1g-17. The first and second channel decoding decoders 1g-15 and 1g-17 can perform the opposite operations of the first and second encoding encoders 1g-11 and 1g-09, respectively.

[0117] In the case of not using an outer code, only the first channel encoding encoder 1g-01, the first channel decoding decoder 1g-05, and the channel 1g-03 are used in the channel encoding block diagram without using the second channel encoding encoder and decoder. Even in the case of not using an outer code, the first channel decoding decoder 1g-05 can have the same configuration as the first channel encoder 1g-11 for the case of using an external encoder.

[0118] In the following description, the eMBB service is referred to as the first type of service, and the eMBB service data is referred to as the first type of data. The terms "first type of service" and "first type of data" are not limited to eMBB, and they can include other service types that require high-speed data transmission or broadband transmission.

[0119] Meanwhile, the URLLC service is referred to as the second type of service, and the URLLC service data is referred to as the second type of data. The terms "second type of service" and "second type of data" are not limited to URLLC, and they can include other service types that require low latency, high-reliability transmission, or low latency and high-reliability transmission.

[0120] Meanwhile, mMTC services are referred to as the third type of service, and mMTC service data is referred to as the third type of data. The terms "third type of service" and "third type of data" are not limited to mMTC, and they may include other service types that require low speed, wide coverage, or low-power transmission. In one embodiment, the first type of service may be understood to include or not include the third type of service.

[0121] The physical layer channel structures for transmitting the three types of services or data may be different from each other. For example, they may be different in at least one of the TTI length, frequency resource allocation unit, control channel structure, and data mapping scheme.

[0122] Although three types of services and three types of data are listed above, the principles of the present invention can be applied to cases where there are a large number of service and data types.

[0123] In an embodiment, the terms "physical channel" and "signal" for LTE and LTE-A systems are used to explain the proposed methods and devices. However, the principles of the present invention are applicable to other wireless communication systems as well as LTE and LTE-A systems.

[0124] As described above, the present invention defines the communication operations between a terminal and a base station for transmitting the first, second, and third types of services or data and proposes a method for serving terminals in such a way as to schedule different types of services or data for each terminal in the same system. In the present invention, the terms "first type of terminal", "second type of terminal", and "third type of terminal" are intended to indicate terminals for which the first, second, and third types of services or data are scheduled, respectively. In an embodiment, the first type of terminal, the second type of terminal, and the third type of terminal may be equal to or different from each other.

[0125] Exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings. A detailed description of well-known functions and structures incorporated herein may be omitted so as not to obscure the subject matter of the present invention. In addition, the following terms are defined in consideration of the functionality in the present invention, and they may vary according to the intention, use, etc. of the user or operator. Therefore, the definitions should be made based on the overall content of this specification. In the following description, the term "base station (BS)" represents an entity for allocating resources to a terminal, and is intended to include at least one of a Node B, an evolved Node B (eNB), a radio access unit, a base station controller, and a network node. The term "terminal" is intended to include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, and a multimedia system having a communication function. The term "downlink (DL)" represents a radio transmission path from the base station to the terminal, and the term "uplink (UL)" represents a radio transmission path from the terminal to the base station. Although the description is directed to an LTE or LTE-A system by way of example, the present invention can be applied to other communication systems having a similar technical background and channel format. For example, the present invention can be applied to 5G mobile communication technology (5G New Radio (NR)) being developed for after LTE-A. Those skilled in the art will understand that the present invention can even be applied to other communication systems with slight modifications without departing from the spirit and scope of the present invention.

[0126] In the present invention, TTI represents a time unit for transmitting control and data signals or only data signals. In a conventional LTE system, by way of example, in the downlink, the TTI is equal to one subframe in length as a time unit, i.e., 1 ms. In the present invention, the TTI can represent a time unit for transmitting control and data signals or only data signals in the uplink. In a conventional LTE system, the TTI is a time unit of 1 ms that is equal to one subframe in both the downlink and the uplink.

[0127] Meanwhile, one of the important criteria for determining the throughput of a wireless cellular communication system is packet data delay. LTE adopts a TTI of 1 ms, which is equal to the length of one subframe. The LTE system adopting a TTI of 1 ms can support UEs operating with a TTI shorter than 1 ms (short-TTI UEs).

[0128] Meanwhile, 5G NR can adopt a TTI shorter than 1 ms. Short-TTI UEs are suitable for delay-sensitive services such as voice over LTE (VoLTE) and remote control services, and are expected to be a means for implementing mission-critical IoT. It is also expected that short-TTI UEs can be a means for implementing cellular-based mission-critical IoT.

[0129] In the present invention, the terms "physical channel" and "signal" for an LTE or LTE-A system may be used interchangeably with the terms "data" or "control signal". For example, although the PDSCH is a physical channel that carries normal-TTI data, in the present invention, it may be referred to as normal-TTI data.

[0130] In the present invention, the uplink grant signal and the downlink data signal are referred to as the first signal. In the present invention, the uplink data signal scheduled by the uplink grant and the HARQ ACK / NACK corresponding to the downlink data signal are referred to as the second signal. In the present invention, if one of the signals sent from the base station to the UE requires a response thereto, it may be the first signal, and the response of the UE to the first signal may be the second signal. In the present invention, the service type of the first signal may fall into three categories: eMBB, mMTC, and URLLC.

[0131] In the present invention, the TTI length of the first signal represents the time length for transmitting the first signal. In the present invention, the TTI length of the second signal represents the time length for transmitting the second signal. In the present invention, the second signal transmission timing represents the information indicating the timing for the UE to transmit the second signal and for the base station to receive the second signal, and it may be referred to as the second signal transmission / reception timing.

[0132] Unless specified for a TDD system, the description is made under the assumption of an FDD system. However, the methods and apparatuses proposed in the present invention for use in an FDD system are applicable to a TTD system with slight modifications.

[0133] In the present invention, the term "higher layer signaling" represents a signaling method for the base station to send a signal to the UE on the downlink data channel of the physical layer or for the UE to send a signal to the base station on the uplink data channel of the physical layer, and may be referred to as RRC signaling or MAC (medium access control) control element (CE) signaling.

[0134] In the following description, the term "transmitter" may be used to indicate the base station in the downlink and the terminal in the uplink. The term "receiver" may be used to indicate the terminal in the downlink and the base station in the uplink.

[0135] In the following description, the term "sub-TB" may be understood to indicate a virtual concept of a bundle of one or more CBs.

[0136] <Example 1>

[0137] Embodiment 1 refers to a method for decomposing a TB into multiple CBs in such a way that the TB is decomposed into multiple sub-TBs and then each sub-TB is decomposed into multiple CBs.

[0138] Figure 1h FIG. is a diagram showing a method for decomposing a TB into M sub-TBs as denoted by reference numeral 1h-01 and decomposing each sub-TB into one or more CBs as denoted by reference numeral 1h-05. Reference numeral 1h-11 represents the TB passed from the higher layer to the physical layer. The physical layer regards the TB 1h-11 as data.

[0139] A CRC 1h-13 can be added to the TB. The CRC 1h-13 can be generated using the TB 1h-11 and a cyclic generator polynomial, which can be defined in various ways. For example, assuming that if L = 24, for a 24-bit CRC cyclic generator polynomial is g CRC24A (D)=D24 + D23 + D18 + D17 + D14 + D11 + D10 + D7 + D6 + D5 + D4 + D3 + D + 1, then it is possible to determine a0D A+23 +a1D A+22 +...+a A-1 D 24 +p0D 23 +p1D 22 +...+p 22 D 1 +p 23 can be divisible by g CRC24A (D) with a remainder of 0 as the CRC CRC p0,p1,p2,p3,...,p L-1 .

[0140] While the description has been made for a case where the CRC length L is 24, L can be set to 12, 16, 24, 32, 40, 48, 64, and so on. After the CRC is added to the TB, the TB is decomposed into M sub-TBs, as indicated by reference numeral 1h-01. That is, the transmission unit resulting from the addition of the CRC to the TB is decomposed into M sub-TBs 1h-21 and 1h-23. For sub-TBs 1h-31 and 1h-35, CRCs 1h-33 and 1h-37 are added, as indicated by reference numeral 1h-03. The CRC added to the sub-TB may differ from the CRC added to the TB in length or in the cyclic generator polynomial used to generate the CRC. The transmission unit resulting from the addition of the CRC to the sub-TB is decomposed into multiple CBs 1h-41, 1h-42, 1h-45, and 1h-47, as indicated by reference numeral 1h-05. For CBs 1h-51, 1h-53, 1h-55, and 1h-57, CRCs 1h-52, 1h-54, 1h-56, and 1h-58 were added, respectively, as indicated by reference numeral 1h-07.

[0141] Figure 1i 、 Figure 1j ,and Figure 1k It shows that Figure 1h An alternative to the method depicted in FIG, Figure 1i 、 Figure 1j ,and Figure 1k Similar markings are referenced in Figure 1h To describe. Unlike Figure 1h A method in which CRC 1h-13 is added to TB, CRCs 1h-33 and 1h-37 are added to sub-TB, and CRCs 1h-52, 1h-54, 1h-56, and 1h-58 are added to CB, Figure 1i In the method of , no CRC is added to the TB, and the difference is that: at 1i-01, the TB is decomposed into M sub-TBs without adding CRC to the TB; for each sub-TB, CRC 1h-33 to 1h-37 are added. This is to reduce the CRC overhead. Figure 1j In the method of , no CRC is added to the sub-TB; Figure 1k In this method no CRC is added to the CB.

[0142] <Example 1-1>

[0143] Embodiment 1-1 is directed to a method for determining the number of sub-TBs in Embodiment 1 and transmitting information of M to a terminal.

[0144] Considering M sub-TBs that make up a TB, the number M of sub-TBs can be determined and notified to the base station or the UE in various ways. For example, it is possible to 1) decompose the TB by the length of the TTI in which data is scheduled, 2) as indicated by specific bits of the downlink control information (DCI), 3) as indicated via RRC signaling, 4) based on the size of the TB, 5) based on the total number of CBs, and use a combination of two or more of 1) to 5) to determine M.

[0145] Method 1) for determining the value of M based on the length of the TTS in which data is scheduled determines the value of M based on how many partial retransmission-available TTIs can be included in the TTI length for the initial transmission. For example, if the initial transmission is scheduled in a time slot including 7 OFDM symbols and the mini-slot consists of 2 or 3 symbols such that three 2-symbol or 3-symbol mini-slots can be included in one time slot, then M is set to 3.

[0146] This is a case where a TB can be composed of 3 sub-TBs. It is also possible to set it to the multiple of 2 closest to 3, the largest multiple of 2 less than 3, or the largest multiple of 2 greater than 3. That is to say, M can be set to 2 or 4 in the above cases. That is, the method for determining M based on the TTI length for scheduling the initial transmission can be changed in various ways.

[0147] Method 2) is for the base station to use specific bits of the DCI as a downlink control signal to notify the terminal of the value of M. The control signal can be a downlink dispatch or an uplink grant. Method 3) is for the base station to notify the terminal of the value of M via RRC signaling. The base station can send the M value information to the terminal via RRC signaling. By combining Method 2) and 3), it is possible to notify the terminal of the value of M via RRC signaling and use 1-bit DCI to indicate that the terminal sends HARQ-ACK bits for each partial retransmission or sub-TB.

[0148] Method 4) for determining the value of M based on the TB size (TBS) is to determine the value of M by comparing the TBS for the initial transmission with a predetermined value. Assume that the maximum allowed size of the CB is Z and the TBS is B. Also assume that the length of the CRC added to the sub-TB is L_sub_TB (L_ sub-TB ), the length of the CRC added to the CB is L_CB (L CB ), and the length of the CRC added to the TB is L_TB (L TB ). Also assume that the number of CBs is C and the number of sub-TBs is M.

[0149] For example, if B is equal to or less than Z, then M = 1, L_sub_TB = 0, C = 1, and L_CB = 0. If B is greater than Z, the value of M is determined as and the value of X can vary with the size of a sub-TB.

[0150] Method 5) for determining the value of M based on the total number of CBs is to determine the value of M by dividing the number of CBs for the initial transmission by a predetermined value. This can aim to fill a sub-TB with as similar a number of CBs as possible.

[0151] <Example 1-2>

[0152] Example 1-2 refers to the method of decomposing a TB into sub-TBs and then into CBs as in Example 1. Example 1-2 is an example of Example 1 and can be varied in various ways. In this example, the value of M is determined based on the TTI length or indicated by specific bits of DCI or via RRC signaling, rather than based on the TBS or the number of CBs. In the following description, N_1 and N_2 can be values greater than 0 and pre-agreed between the transmitter and the receiver, and they can represent the CRC lengths for CBs and sub-TBs, respectively.

[0153] In the following description, represents an integer greater than X and represents the largest integer less than X. In the present invention, a sub-TB can be understood as a virtual concept and a unit of a bundle of one or more CBs.

[0154] The total number "C" of CBs can be determined as follows.

[0155]

[0156]

[0157] In the above method, it is possible that a sub-TB consists of one CB, and the method can be modified so that a sub-TB consists of at least X CBs as follows.

[0158]

[0159]

[0160] Throughout the above method, the CRC lengths of sub-TBs and CBs, the numbers of sub-TBs and CBs, and the total number of bits B' of the data to be transmitted are determined. The method of decomposing a TB into sub-TBs and CBs is described below. In the following description, c rk represents the k-th bit of the r-th CB.

[0161] Calculate the number of bits per CB:

[0162] First segment size: K + is a minimum value included in a specific set among K values that satisfy B'≤C·K (the specific set may be a set including values agreed in advance between the transmitter and the receiver).

[0163] if C=1

[0164] With size K + The number of CBs: C + =1,K - =0,C - =0

[0165] else if C>1

[0166] Second segment size: K - Is to meet K <K + The maximum value included in a specific set among the K values of (the specific set may be a set including values agreed in advance between the transmitter and the receiver).

[0167] Δ K =K + -K -

[0168] With size K - Number of CBs:

[0169] With size K + The number of CBs: C+ = CC-

[0170] end if

[0171] The number of large CBs included in a sub-TB is N + : The smallest integer among the values of N that satisfies C≤M·N

[0172] The number of small CBs included in a sub-TB is N - : The largest integer among the values of N that satisfy M·N≤C

[0173] Number of sub-TBs each with N CBs: M - =M·N + -C

[0174] Number of sub-TBs each with N+ CBs: M + =M-(M·N + -C)

[0175] Number of 0 or NULL padding bits: F = C + ·K+ +C - ·K - -B'

[0176]

[0177]

[0178]

[0179] In addition, in the above embodiments, zero or null padding bits are inserted at the beginning by way of example, and it is possible to insert padding bits in the middle or at the end.

[0180] In the above embodiments, by way of example, sub-TBs with a small number of CBs are arranged at the beginning of the TB. Assuming 10 CBs and M = 3, that is, the number of sub-TBs is 3, then sub-TBs with 3, 3, and 4 CBs respectively are arranged in sequence. This means that sub-TBs including more CBs are arranged at the beginning.

[0181] Figure 1l is a flowchart showing a method for a transmitter to decompose a TB into one or more sub-TBs and then into one or more CBs and add CRCs to the sub-TBs and CBs. At 1l-02, the base station sends information about the number M of sub-TBs to the terminal or assumes a pre-agreed value of M; at 1l-04, the total number of CBs, the number of CBs included in the sub-TB, the length of the CB, etc. are calculated; at 1l-06, CRCs are added to the CBs and sub-TBs of the data to be sent.

[0182] Figure 1m is a flowchart showing a method for a receiver to identify one or more sub-TBs and one or more CBs to decode the TB and use the CRCs added to the sub-TBs and CBs to determine whether the TB is successfully decoded. At 1m-02, the base station sends information about the number of sub-TBs to the terminal or assumes a pre-agreed value of M; at 1m-04, the total number of CBs, the number of CBs included in the sub-TB, the length of the CB, etc. are calculated; at 1m-06, after decoding the CBs, the CRCs attached to the CBs and sub-TBs are checked to determine whether the decoding of the CBs and sub-TBs is successful.

[0183] <Embodiment 2>

[0184] Embodiment 2 refers to a method for a terminal to determine the CRC length based on the CRC length information sent by the base station and configure the CRC per CB based on the determined CRC length, which will be described with reference to Figure 1n and Figure 1o description.

[0185] When performing downlink or uplink data transmission, the base station sends the length information of the CRC to be attached to each CB to the terminal. The CRC length information is 1) sent to the terminal via RRC signaling, 2) configured in the transmission applying the partial retransmission technique, or 3) sent via specific bits of DCI.

[0186] In the method 1) based on RRC signaling, for example, if an RRC variable such as long_CRC_PDSCH is set to 1, it is possible to apply a 32-bit or 48-bit CRC instead of a 23-bit CRC. In the method 2) based on the application of the partial retransmission technique, it is possible to set an RRC variable such as partial_retransmission to "active" or send DCI indicating partial retransmission. In the method 3) based on specific bits of DCI, it is possible to set specific bits to indicate whether to use a short CRC or a long-length CRC. The short-length CRC can have a length of 16 bits or 24 bits, and the long-length CRC can have a length of 32 bits, 40 bits, or 48 bits.

[0187] Figure 1n is a flowchart showing a process in which a transmitter provides CRC length information and performs transmission using a CRC having a predetermined CRC length. At step 1n-02, the CRC length information can be pre-agreed between the base station and the terminal, or sent from the base station to the terminal. At step 1n-04, the base station calculates a CRC having a predetermined length based on the data bits and adds the CRC to the CB. It is possible to use a predetermined cyclic generator polynomial for calculating the CRC. At step 1n-06, the CB with the added CRC can be encoded with a channel code.

[0188] Figure 1o is a flowchart showing a process in which a receiver uses a CRC having a predetermined length obtained from the CRC length information to determine whether signal reception is successful. At step 1o-02, the CRC length information can be pre-agreed between the base station and the terminal, or sent from the base station to the terminal. At step 1o-04, the receiver decodes the channel code through the CB. After the channel code decoding, at step 10o-06, the receiver checks the CRC having a predetermined length to determine whether the decoding is successful. The CRC test can be performed using the cyclic generator polynomial used by the transmitter for generating the CRC.

[0189] <Example 3>

[0190] Example 3 refers to a method for determining the CRC length based on the service type of the data being transmitted.

[0191] It is possible that for the base station and the terminal, it is assumed that the CRC length varies depending on whether the provided service is an eMBB service, a URLLC service, or an mMTC service. It can be pre-agreed that the length of the CRC added to the CB is 24 bits for the eMBB service, 32 bits or 40 bits for the URLLC service, and 16 bits, 24 bits, or 32 bits for the mMTC service. This may be because the required HARQ-ACK reliability varies with the service.

[0192] <Example 4>

[0193] Example 4 refers to a method for a transmitter to perform retransmission via a sub-TB based on HARQ-ACK information generated by a receiver via a sub-TB and sent to the transmitter, which will be described with reference to Figure 1p and Figure 1q description.

[0194] Figure 1p is a flowchart showing the process for a receiver to send HARQ-ACK information via a sub-TB. At step 1p-02, the base station and the terminal can share information about the number M of sub-TBs and the CRC length. The shared information can be sent from the base station to the UE via RRC signaling or DCI, or shared according to a pre-agreed method. At step 1p-04, the receiver performs channel code decoding and checks the CRC attached to the CB and the sub-TB to determine whether a specific sub-TB has been successfully transmitted. At step 1p-06, the receiver sends HARQ-ACK feedback information indicating whether the sub-TB has been successfully received to the transmitter. The HARQ-ACK feedback information can include the number of bits corresponding to each sub-TB or a bundle of sub-TBs. After sending the HARQ-ACK feedback information, the receiver can perform decoding on the sub-TB that failed in the initial transmission under the assumption of retransmission by the sub-TB.

[0195] Figure 1q is a flowchart showing the process for a transmitter to perform retransmission via a sub-TB based on the HARQ-ACK information sent by the sub-TB. At step 1q-02, the base station and the terminal share information about the number M of sub-TBs and the CRC length. The shared information can be sent from the base station to the UE via RRC signaling or DCI, or shared according to a pre-agreed method. At step 1q-04, the transmitter checks the HARQ-ACK feedback information for the sub-TB that failed to be transmitted sent by the receiver. The HARQ-ACK feedback information can include the number of bits corresponding to each sub-TB or a bundle of sub-TBs. At step 1q-06, the transmitter retransmits the negative acknowledged (NACKed) sub-TB.

[0196] Each terminal and base station consisting of a transmitter, a receiver, and a processor for implementing the methods of the above embodiments are respectively in Figure 1r and Figure 1s are depicted. To implement the methods of Embodiments 1 to 4 for determining the schemes for attaching CRC by sub-TB, CB, and TB and communicating and transmitting signals between the base station and the terminal based on the CRC attachment schemes, the transmitter, receiver, and processor of each of the base station and the UE should operate as described in the respective embodiments.

[0197] Figure 1r is a block diagram showing the configuration of a UE according to an embodiment of the present invention. As Figure 1r shown, the UE may include a processor 1r-02, a receiver 1r-00, and a transmitter 1r-04. According to an embodiment of the present invention, the receiver 1r-00 and the transmitter 1r-04 may be collectively referred to as a transceiver. The transceiver may send signals to the base station and receive signals from the base station. The signals may include control information and data. The transceiver may include: an RF transmitter for frequency-up-converting and amplifying the signals to be sent; and an RF receiver for low-noise amplifying and frequency-down-converting the received signals. The transceiver may output the signals received over the radio channel to the processor 1r-02, and send the signals output from the processor 1r-02 over the radio channel. According to an embodiment of the present invention, the processor 1r-02 may control the overall operation of the UE. For example, the processor 1r-02 may control the receiver 1r-02 to receive a downlink data signal from the base station, and determine whether the decoding is successful through the CRC tests performed by the CB and the sub-TB. Thereafter, the transmitter 1r-04 may send HARQ-ACK feedback information through the sub-TB.

[0198] Figure 1s is a block diagram showing the configuration of a base station according to an embodiment of the present invention. As Figure 1sAs shown in [Figure 0], the base station may include a processor 1s-03, a receiver 1s-01, and a transmitter 1s-05. According to an embodiment of the present invention, the receiver 1s-01 and the transmitter 1s-05 may be collectively referred to as a transceiver. The transceiver may send signals to the terminal and receive signals from the terminal. The signals may include control information and data. The transceiver may include: an RF transmitter for frequency up-converting and amplifying the signal to be sent; and an RF receiver for low-noise amplifying and frequency down-converting the received signal. The transceiver may output the signal received over the radio channel to the processor 1s-03, and send the signal output from the processor 1s-03 over the radio channel. According to an embodiment of the present invention, the processor 1s-03 may control the overall operation of the base station. For example, the processor 1s-03 may determine the number M of sub-TBs and control to generate and send the corresponding information to the terminal. Thereafter, the transmitter 1s-05 adds CRC to the CB and sub-TBs and sends the corresponding data, and the receiver 1s-01 receives HARQ-ACK information from the terminal through the sub-TBs.

[0199] According to an embodiment of the present invention, the processor 1s-03 may control to generate downlink control information (DCI) or higher layer signaling signals including the number of sub-TBs and the CRC length. In this case, the DCI or higher layer signaling signals may include information indicating whether the number of sub-TBs and the CRC length are included therein.

[0200] The embodiments disclosed in the specification and the drawings are presented to assist in the explanation and understanding of the present invention, rather than to limit the scope of the present invention. It will be apparent to those skilled in the art that modifications and changes can be made thereto without departing from the spirit and scope of the present invention. If necessary, the embodiments can be implemented in whole or in part in combination. For example, the base station and the UE may operate according to a combination of parts of Embodiments 1 to 4 of the present invention. Although the embodiments are directed to the FDD LTE system, the present invention can include alternative embodiments directed to other systems such as the TDD LTE and 5G NR systems without departing from the technical spirit of the present invention.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receiving, from a base station, information on the number of code block groups for each transport block TB, where each code block group includes at least one code block; Receiving, from the base station, the TB and control information for scheduling the TB; Determining the number of code block groups for the TB based on the number of code blocks of the TB and the information; Decoding the TB based on the code block groups; Generating hybrid automatic repeat request HARQ feedback information bits for the code block groups based on the decoding, where one bit in the HARQ feedback information bits corresponds to one code block group; and Sending the HARQ feedback information bits to the base station on an uplink channel, where the number of code blocks of the TB is determined based on the transport block size TBS, and the TBS is determined based on the control information, and where the number of code blocks for each code block group is determined based on the number of code blocks of the TB.

2. The method according to claim 1, wherein The information on the number of code block groups for each TB is received by radio resource control RRC signaling.

3. The method according to claim 1, wherein, The size of the HARQ feedback information bits is determined based on the information on the number of code block groups for each TB.

4. The method according to claim 3, wherein One bit in the HARQ feedback information bits corresponds to an acknowledgement ACK or negative acknowledgement NACK for one of the code block groups.

5. A method performed by a base station in a wireless communication system, the method comprising: Sending, to a terminal, information on the number of code block groups for each transport block TB, where each code block group includes at least one code block; Determining the number of code block groups for the TB based on the number of code blocks of the TB and the information; Sending the code block groups of the TB and the control information for scheduling the TB to the terminal; and Receiving, on an uplink channel from the terminal, hybrid automatic repeat request HARQ feedback information bits for the code block groups, where one bit in the HARQ feedback information bits corresponds to one code block group, where the number of code blocks of the TB is determined based on the transport block size TBS, and the TBS is determined based on the control information, and where the number of code blocks for each code block group is determined based on the number of code blocks of the TB.

6. The method according to claim 5, wherein, The information on the number of code block groups for each TB is sent by radio resource control RRC signaling.

7. The method according to claim 5, wherein The size of the HARQ feedback information bits is the same as the number of code block groups for each TB.

8. The method according to claim 7, wherein One bit in the HARQ feedback information bits corresponds to an acknowledgement ACK or negative acknowledgement NACK for one of the code block groups.

9. A terminal in a wireless communication system, the terminal comprising: A transceiver; And A controller configured to: Control the transceiver to receive, from a base station, information on the number of code block groups for each transport block TB, where each code block group includes at least one code block, Control the transceiver to receive the TB and the control information for scheduling the TB from the base station, Determine the number of code block groups for the TB according to the number of code blocks of the TB and the information, Decode the TB according to the code block groups, Generate hybrid automatic repeat request HARQ feedback information bits for the code block groups based on the decoding, where one bit in the HARQ feedback information bits corresponds to one code block group, and Control the transceiver to send HARQ feedback information bits to the base station on an uplink channel, wherein the number of code blocks of a transport block (TB) is determined based on the transport block size (TBS), the TBS is determined based on control information, and wherein the number of code blocks of each code block group is determined based on the number of code blocks of the TB.

10. The terminal according to claim 9, wherein, Information about the number of code block groups for each TB is received by radio resource control (RRC) signaling.

11. The terminal according to claim 9, wherein, The size of the HARQ feedback information bits is the same as the number of code block groups for each TB.

12. The terminal according to claim 11, wherein, One bit in the HARQ feedback information bits corresponds to an acknowledgement (ACK) or negative acknowledgement (NACK) for one of the code block groups.

13. A base station in a wireless communication system, the base station comprising: A transceiver; And A controller configured to: Control the transceiver to send information about the number of code block groups for each transport block (TB) to a terminal, wherein each code block group includes at least one code block, Determine the number of code block groups of the TB according to the number of code blocks of the TB and the information, Control the transceiver to send the code block groups of the TB and the control information scheduling the TB to the terminal, and Control the transceiver to receive, on an uplink channel, hybrid automatic repeat request (HARQ) feedback information bits of the identified code block groups from the terminal, one bit in the HARQ feedback information bits corresponding to one code block group, wherein the number of code blocks of a TB is determined based on the transport block size (TBS), and the TBS is determined based on control information, wherein the number of code blocks of each code block group is determined based on the number of code blocks of the TB.

14. The base station according to claim 13, wherein, Information about the number of code block groups for each TB is sent by radio resource control (RRC) signaling.

15. The base station according to claim 13, wherein, The size of the HARQ feedback information bits is the same as the number of code block groups for each TB.

16. The base station according to claim 15, wherein, One bit in the HARQ feedback information bits corresponds to an acknowledgement (ACK) or negative acknowledgement (NACK) for one of the code block groups.

Images