Method and apparatus for transmitting and receiving radio signals in a wireless communication system

Abstract

The present invention relates to a method and apparatus for transmitting and receiving a radio signal in a wireless communication system. The present invention relates to a wireless communication system, and more specifically, to a method, comprising: performing decoding on a CBG configuring a TB; after the decoding, receiving the TB again; and sending a plurality of HARQ-ACK bits for receiving the TB again, each HARQ-ACK bit representing a HARQ-ACK response of each CBG for the TB, and among the plurality of HARQ-ACK bits, the HARQ-ACK bit of the first CBG successfully decoded before receiving the TB again is mapped to ACK, regardless of whether the first CBG is received when receiving the TB again.

Description

[0001] This application is a divisional application of a patent application with application number 201880016978.3 (PCT / KR2018 / 002743), which was submitted to the China Patent Office on September 9, 2019, with an international application date of March 8, 2018, and the invention name is “Method and device for sending and receiving radio signals in a wireless communication system”. Technical Field

[0002] The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for transmitting / receiving a wireless signal. The wireless communication system includes a wireless communication system based on carrier aggregation (CA). Background Art

[0003] Wireless communication systems have been widely used to provide various communication services, such as voice or data services. Generally, wireless communication systems are multiple access systems that can communicate with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of various multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, etc. Summary of the invention

[0004] Technical issues

[0005] An object of the present invention is to provide a method and apparatus for effectively performing a radio signal transceiving process.

[0006] It should be understood that the technical objectives to be achieved by the present invention are not limited to the above-mentioned technical objectives, and other technical objectives not mentioned herein will be obvious to ordinary technicians in the field to which the present invention belongs based on the following description.

[0007] Technical Solution

[0008] In one aspect of the present invention, a method for sending control information by a user equipment in a wireless communication system is provided, comprising: receiving information about the number M of code block groups defined for a transport block from a base station via an upper layer signal; receiving a first transport block including multiple code blocks from the base station via a physical layer channel; and sending a hybrid ARQ response (HARQ-ACK) payload including HARQ-ACK information about the first transport block to the base station, wherein a code block-based cyclic redundancy check (CRC) is attached to each code block, wherein the transport block-based CRC is attached to the first transport block, and wherein the HARQ-ACK payload includes multiple HARQ-ACK bits corresponding to the M code block groups of the first transport block.

[0009] In another aspect of the present invention, a user equipment for use in a wireless communication system is provided, comprising a radio frequency (RF) module and a processor, the processor being configured to receive information about the number M of code block groups defined for a transport block from a base station via an upper layer signal, receive a first transport block including multiple code blocks from the base station via a physical layer channel, and send a hybrid ARQ response (HARQ-ACK) payload including HARQ-ACK information about the first transport block to the base station, wherein a code block-based cyclic redundancy check (CRC) is attached to each code block, wherein the transport block-based CRC is attached to the first transport block, and wherein the HARQ-ACK payload includes multiple HARQ-ACK bits corresponding to the M code block groups of the first transport block.

[0010] Preferably, the upper layer signal may include a radio resource control (RRC) signal, and the physical layer channel may include a physical downlink shared channel (PDSCH).

[0011] Preferably, during the HARQ process for the first transport block, the size of the HARQ-ACK payload may be maintained the same based on M.

[0012] Preferably, in the case where the first transport block is configured by multiple code block groups, some of the multiple code block groups may include ceiling (K / M) code blocks, and the remaining code block groups in the multiple code block groups include flooring (K / M) code blocks, and wherein ceiling is an ascending function, flooring is a descending function, and K indicates the number of code blocks in the first transport block.

[0013] Preferably, in the case where a code block group is configured for the first transport block, each HARQ-ACK bit in the HARQ-ACK payload may indicate each HARQ-ACK information generated in units of a code block group for the first transport block.

[0014] Preferably, without configuring a code block group for the first transport block, multiple HARQ-ACK bits for the first transport block in the HARQ-ACK payload may have the same value, and each HARQ-ACK bit for the first transport block may indicate HARQ-ACK information generated for the first transport block in units of transport block groups.

[0015] Preferably, when all code block group-based CRC check results for the first transport block are "successful" but the transport block-based CRC check results are "failed", all multiple HARQ-ACK bits for the first transport block in the HARQ-ACK payload can indicate a negative acknowledgement (NACK).

[0016] In another aspect of the present invention, a method for receiving control information by a base station in a wireless communication system is provided, the method comprising: sending information about the number M of code block groups defined for a transport block to a user equipment through an upper layer signal; sending a first transport block including multiple code blocks to the user equipment through a physical layer channel; and receiving a hybrid ARQ response (HARQ-ACK) payload including HARQ-ACK information about the first transport block from the user equipment, wherein a code block-based cyclic redundancy check (CRC) is attached to each code block, wherein the transport block-based CRC is attached to the first transport block, and wherein the HARQ-ACK payload includes multiple HARQ-ACK bits for the M code block groups of the first transport block.

[0017] In another aspect of the present invention, a base station for use in a wireless communication system is provided, the base station comprising a radio frequency (RF) module and a processor, the processor being configured to send information about the number M of code block groups defined for a transport block to a user equipment via an upper layer signal; send a first transport block comprising multiple code blocks to the user equipment via a physical layer channel, and receive a hybrid ARQ response (HARQ-ACK) payload including HARQ-ACK information about the first transport block from the user equipment, wherein a code block-based cyclic redundancy check (CRC) is attached to each code block, wherein the transport block-based CRC is attached to the first transport block, and wherein the HARQ-ACK payload includes multiple HARQ-ACK bits corresponding to the M code block groups of the first transport block.

[0018] Beneficial Effects

[0019] According to the present invention, it is possible to efficiently transmit and receive radio signals in a wireless communication system.

[0020] Those skilled in the art will understand that the effects that can be achieved by the present invention are not limited to the effects that have been specifically described above, and other advantages of the present invention will be more clearly understood from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are included as a part of the detailed description to provide a further understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the technical principles of the invention.

[0022] Figure 1 is a conceptual diagram illustrating physical channels used in a 3GPP LTE(-A) system serving as an exemplary wireless communication system and a general method of transmitting a signal using the physical channels.

[0023] Figure 2 is a diagram illustrating the structure of a radio frame.

[0024] Figure 3 A resource grid of a downlink time slot is exemplarily shown.

[0025] Figure 4 The figure shows the downlink subframe structure.

[0026] Figure 5 EPDCCH (Enhanced Physical Downlink Control Channel) is exemplarily shown.

[0027] Figure 6 The structure of an uplink (UL) subframe used for LTE / LTE-A is exemplarily shown.

[0028] Figure 7 SC-FDMA (Single Carrier Frequency Division Multiple Access) and OFDMA (Orthogonal Frequency Division Multiple Access) are exemplarily shown.

[0029] Figure 8 A UL HARQ (Uplink Hybrid Automatic Repeat Request) operation is exemplarily shown.

[0030] Fig. 9 The transport block (TB) processing procedure is exemplarily shown.

[0031] Fig.10 and Fig.11 The random access procedure is exemplarily shown.

[0032] Fig.12 A carrier aggregation (CA) communication system is exemplarily shown.

[0033] Fig.13 The cross-carrier scheduling is exemplarily shown.

[0034] Fig.14 Analog beamforming is shown exemplarily.

[0035] Fig.15 The structure of a self-contained subframe is exemplarily shown.

[0036] Fig.16 and Fig.17 The signaling according to the invention is shown by way of example.

[0037] Fig.18 A base station (BS) and a user equipment (UE) applicable to the embodiments of the present invention are exemplarily shown. DETAILED DESCRIPTION

[0038] The following embodiments of the present invention can be applied to various wireless access technologies, such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, etc. CDMA can be implemented by wireless communication technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented by wireless communication technologies such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rate for GSM Evolution (EDGE), etc. OFDMA can be implemented by wireless communication technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, E-UTRA (Evolved UTRA), etc. UTRA is part of Universal Mobile Telecommunications System (UMTS). The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of Evolved UMTS (E-UMTS) using E-UTRA. LTE Advanced (LTE-A) is an evolved version of 3GPP LTE. Although the following embodiments of the present invention will describe technical features of the present invention based on 3GPP LTE / LTE-A system hereinafter, it should be noted that the following embodiments will be disclosed for illustrative purposes only and the scope and spirit of the present invention are not limited thereto.

[0039] In a wireless communication system, a UE (User Equipment) receives information from a BS (Base Station) through a downlink (DL), and the UE transmits information to the BS through an uplink (UL). Information transmitted and received between the BS and the UE includes data and various control information, and various physical channels exist according to the type / purpose of the information transmitted and received by them.

[0040] Figure 1 The figure shows physical channels used in the 3GPP LTE(-A) system and a general signal transmission method using the physical channels.

[0041] When the power is turned on in the power-off state or when the UE initially enters the cell, the UE performs an initial cell search operation such as synchronization with the BS in step S101. To this end, the UE synchronizes with the BS by receiving the primary synchronization channel (P-SCH) and the secondary synchronization channel (S-SCH) from the BS and obtains information such as a cell identifier (ID). The UE can then receive the physical broadcast channel (PBCH) from the BS to obtain intra-cell broadcast information. At the same time, the UE can confirm the downlink channel state by receiving a downlink reference signal (DL RS) during the initial cell search.

[0042] The UE that has completed the initial cell search may acquire more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on information of the PDCCH in step S102.

[0043] Afterwards, the UE may perform a random access procedure such as steps S103 to S106 to access the BS. To this end, the UE may transmit a preamble through a physical random access channel (PRACH) (S103), and receive a response message to the preamble through a PDCCH and a PDSCH corresponding to the PDCCH (S104). In the case of contention-based random access, the UE may perform a contention resolution procedure such as further PRACH transmission (S105) and reception of a PDCCH and a PDSCH corresponding to the PDCCH (S106).

[0044] After the aforementioned process, as a general downlink / uplink signal transmission process, the UE may receive PDCCH / PDSCH (S107) and transmit a physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) (S108). Here, the control information sent from the UE to the BS is collectively referred to as uplink control information (UCI). UCI may include a hybrid automatic repeat request (HARQ) acknowledgement (ACK) / negative-ACK (HARQ-ACK / NACK) signal, a scheduling request (SR), a channel state information (CSI), and the like. CSI includes a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and the like. Although UCI is usually transmitted through PUCCH, it may be transmitted through PUSCH when control information and service data need to be transmitted simultaneously. In addition, UCI may be transmitted aperiodically through PUSCH according to the request / instruction of the network.

[0045] Figure 2 Figure 1 shows a radio frame structure. Uplink / downlink data packet transmission is performed in units of subframes, and a subframe is defined as a time interval including a plurality of symbols. 3GPP LTE supports a type 1 radio frame structure applicable to FDD (frequency division duplex) and a type 2 radio frame structure applicable to TDD (time division duplex).

[0046] Figure 2 (a) illustrates a type 1 radio frame structure. A downlink subframe includes 10 subframes, each of which includes two time slots in the time domain. The time for sending one subframe is defined as a transmission time interval (TTI). For example, one subframe has a length of 1 ms and one time slot has a length of 0.5 ms. One time slot includes multiple OFDM symbols in the time domain and multiple resource blocks (RBs) in the frequency domain. Because OFDM is used in the downlink in 3GPP LTE, an OFDM symbol represents a symbol period. An OFDM symbol may be referred to as an SC-FDMA symbol or a symbol period. An RB, as a resource allocation unit, may include multiple consecutive subcarriers in one time slot.

[0047] The number of OFDM symbols included in a time slot may vary according to a cyclic prefix (CP) configuration. The CP includes an extended CP and a normal CP. For example, when an OFDM symbol is configured with a normal CP, the number of OFDM symbols included in one time slot may be 7. When an OFDM symbol is configured with an extended CP, the length of one OFDM symbol increases, and thus the number of OFDM symbols included in one time slot is less than in the case of a normal CP. For example, in the case of an extended CP, the number of OFDM symbols included in one time slot may be 6. When the channel state is unstable, such as when the UE moves at high speed, an extended CP can be used to reduce inter-symbol interference.

[0048] When a normal CP is used, a subframe includes 14 OFDM symbols because a slot includes 7 OFDM symbols. Up to the first three OFDM symbols in each subframe can be allocated to the PDCCH and the remaining OFDM symbols can be allocated to the PDSCH.

[0049] Figure 2 (b) illustrates a type 2 radio frame structure. A type 2 radio frame includes 2 half frames. Each half frame includes 4 (5) normal subframes and 1 (0) special subframe. Depending on the UL-DL configuration, a normal subframe is used for uplink or downlink. A subframe includes 2 time slots.

[0050] Table 1 shows a subframe structure in a radio frame according to UL-DL configuration.

[0051] [Table 1]

[0052]

[0053] In Table 1, D represents a downlink subframe, U represents an uplink subframe and S represents a special subframe. The special subframe includes a DwPTS (downlink pilot time slot), a GP (guard period), and an UpPTS (uplink pilot time slot). The DwPTS is used for initial cell search, synchronization or channel estimation in the UE. The UpPTS is used for channel estimation in the BS and UL transmission synchronization of the UE. The GP eliminates interference between the UL and DL caused in the UL due to multipath delay of the DL signal.

[0054] The radio frame structure is merely exemplary, and the number of subframes, the number of slots, and the number of symbols in a radio frame can vary.

[0055] Figure 3 A resource grid for a downlink time slot is shown.

[0056] refer to Figure 3, a downlink time slot includes multiple OFDM symbols in the time domain. An example is that a downlink time slot may include 7 OFDM symbols and a resource block (RB) may include 12 subcarriers in the frequency domain. However, the present invention is not limited to this. Each element on the resource grid is called a resource element (RE). An RB includes 12×7 REs. The number of RBs included in the downlink time slot N DL Depends on the downlink transmission bandwidth. The structure of the uplink time slot can be the same as that of the downlink time slot.

[0057] Figure 4 The figure shows the downlink subframe structure.

[0058] refer to Figure 4 , a maximum of three (four) OFDM symbols located in the front of the first time slot within a subframe correspond to the control region to which the control channel is allocated. The remaining OFDM symbols correspond to the data region to which the physical downlink shared channel (PDSCH) is allocated, and the basic resource unit of the data region is RB. Examples of downlink control channels used in LTE include physical control format indicator channel (PCFICH), physical downlink control channel (PDCCH), physical hybrid ARQ indicator channel (PHICH), etc. PCFICH is transmitted at the first OFDM symbol of a subframe and carries information about the number of OFDM symbols used for control channel transmission within the subframe. PHICH is a response to uplink transmission and carries HARQ acknowledgement (ACK) / negative acknowledgement (NACK) signals. The control information transmitted through PDCCH is called downlink control information (DCI). DCI includes uplink or downlink scheduling information or uplink transmission power control commands for any UE group.

[0059] The control information sent by PDCCH is called DCI. Formats 0, 3, 3A, 4 for uplink and formats 1, 1A, 1B, 1C, 1D, 2, 2A, 2B and 2C for downlink are defined as DCI formats. The type of information field, the number of information fields and the number of bits of each information field vary according to the DIC format. For example, the DCI format selectively includes information such as frequency hopping flag, RB allocation, MCS (modulation and coding scheme), RV (redundancy version), NDI (new data indicator), TPC (transmit power control), HARQ process number, PMI (precoding matrix indicator) confirmation, etc. according to its use. Therefore, the size of the control information integrated into the DCI format varies according to the DCI format. On the other hand, any DCI format can be used to send two or more types of control information. For example, DIC format 0 / 1A is used to carry DCI format 0 or DCI format 1, which are distinguished from each other by the flag field.

[0060] PDCCH can carry the transmission format and resource allocation of the downlink shared channel (DL-SCH), resource allocation information of the uplink shared channel (UL-SCH), paging information about the paging channel (PCH), system information on the DL-SCH, resource allocation information of the upper layer control message such as the random access response sent on the PDSCH, the transmission power control command of a single UE in any UE group, activation information of IP voice (VoIP), etc. Multiple PDCCHs can be sent in the control region. The UE is able to monitor multiple PDCCHs. The PDCCH is sent on the aggregation of one or several consecutive control channel elements (CCEs). CCE is a logical allocation unit used to provide a PDCCH with a given coding rate based on the state of the radio channel. CCE corresponds to multiple resource element groups (REGs). The format of the PDCCH and the number of bits of the available PDCCH are determined by the correlation between the number of CCEs and the coding rate provided by the CCE. The BS determines the PDCCH format according to the DCI to be sent to the UE and attaches a cyclic redundancy check (CRC) to the control information. Depending on the owner or purpose of the PDCCH, the CRC is masked with a unique identifier (referred to as a radio network temporary identifier (RNTI)). If the PDCCH is for a specific UE, the unique identifier of the UE (e.g., cell-RNTI (C-RNTI)) may be masked to the CRC. Alternatively, if the PDCCH is used for a paging message, a paging indication identifier (e.g., paging-RNTI (P-RNTI)) may be masked to the CRC. If the PDCCH is used for system information (more specifically, the system information block (SIB) described below), a system information identifier (e.g., system information RNTI (SI-RNTI)) may be masked to the CRC. In order to indicate a random access response, which is a response to the transmission of a random access preamble to the UE, a random access-RNTI (RA-RNTI) may be masked to the CRC.

[0061] The PDCCH carries a message called DCI, which includes resource assignment information and other control information used for a UE or UE group. Typically, multiple PDCCHs can be sent in one subframe. Each PDCCH is sent using one or more CCEs, each CCE corresponding to 9 sets of 4 REs. 4 REs are called REGs. 4 QPSK symbols are mapped to one REG. REs allocated to reference signals are not included in the REG, and therefore the total number of REGs in a given OFDM symbol varies depending on the presence or absence of cell-specific reference signals. The REG concept (i.e., mapping in groups, each group including 4 REs) is also used for other downlink control channels (PCFICH and PHICH). That is, REG is used as the basic resource unit of the control area. Four PDCCH formats are supported, as shown in Table 2.

[0062] [Table 2]

[0063]

[0064]

[0065] The CCEs are numbered consecutively and used. In order to simplify the decoding process, a PDCCH having a format including n CCEs can be initiated only on a number of CCEs that is the same as a multiple of n. The number of CCEs used to send a specific PDCCH is determined by the BS according to the channel state. For example, in the case of a UE with a good downlink channel for PDCCH (e.g., adjacent to the BS), one CCE may be sufficient. However, in the case of a UE with a poor channel (e.g., located near the edge of a cell), eight CCEs may be required to obtain sufficient robustness. In addition, the power level of the PDCCH can be adjusted according to the channel state.

[0066] The solution introduced in LTE is to define the CCE positions in a restricted set where the PDCCH can be located for each UE. The CCE positions in the restricted set where the UE can find its own PDCCH can be called the search space (SS). In LTE, the SS has a size that depends on the PDCCH format. In addition, the UE-specific search space (USS) and the common search space (CSS) are defined separately. The USS is set separately for each UE, and the range of the CCS is signaled to all UEs. For a given UE, the USS and CSS may overlap. In the case of a relatively small SS, when part of the CCE positions are allocated in the search space for a specific UE, there are no remaining CCEs, so the BS may not find CCE resources to send PDCCH to all available UEs within a given subframe. In order to minimize the possibility of this blocking continuing to the next subframe, a UE-specific hopping sequence is applied to the starting point of the USS.

[0067] Table 3 shows the sizes of CSS and USS.

[0068] [Table 3]

[0069]

[0070] In order to control the computational load of blind decoding based on the number of blind decoding processes to an appropriate level, the UE is not required to search for all defined DCI formats at the same time. Typically, the UE always searches for formats 0 and 1A in the USS. Formats 0 and 1A have the same size and are distinguished from each other by flags in the message. In addition, the UE may need to receive additional formats (e.g., formats 1, 1B, or 2 according to the PDSCH transmission mode set by the BS). The UE searches for formats 1A and 1C in the CSS. In addition, the UE can be set to search for formats 3 or 3A. Formats 3 and 3A have the same size as formats 0 and 1A, and can be distinguished by scrambling the CRC with different (common) identifiers rather than UE-specific identifiers. The information content of the PDSCH transmission scheme and DCI format according to the transmission mode (TM) is listed below.

[0071] Transmit Mode (TM)

[0072] Transmission mode 1: Transmission from a single base station antenna port

[0073] Transmit mode 2: Transmit diversity

[0074] Transmission mode 3: Open loop spatial multiplexing

[0075] Transmission mode 4: Closed-loop spatial multiplexing

[0076] Transmission mode 5: Multi-user MIMO (Multiple Input Multiple Output)

[0077] Transmission mode 6: Closed-loop rank 1 precoding

[0078] Transmit mode 7: Single antenna port (port 5) transmission

[0079] Transmission mode 8: dual-layer transmission (ports 7 and 8) or single antenna port (port 7 or 8) transmission

[0080] Transmission mode 9: Transmission of up to 8 layers (ports 7 to 14) or transmission of a single antenna port (port 7 or 8)

[0081] DCI format

[0082] Format 0: Resource grant for PUSCH transmission (uplink)

[0083] Format 1: Resource assignment for single codeword PDSCH transmission (transmission modes 1, 2, and 7)

[0084] Format 1A: Compact signaling for resource assignment for single codeword PDSCH (all modes)

[0085] Format 1B: Compact resource assignment for rank 1 closed-loop precoded PDSCH (mode 6)

[0086] Format 1C: Very compact resource assignment for PDSCH (e.g., paging / broadcast system information)

[0087] Format 1D: Compact resource assignment for PDSCH (Mode 5) using multi-user MIMO

[0088] Format 2: Resource assignment for PDSCH (Mode 4) for closed-loop MIMO operation

[0089] Format 2A: Resource assignment for PDSCH (Mode 3) for open-loop MIMO operation

[0090] Format 3 / 3A: Power control command with 2-bit / 1-bit power adjustment value for PUCCH and PUSCH

[0091] Figure 5 The figure shows EPDCCH. EPDCCH is a channel additionally introduced in LTE-A.

[0092] refer to Figure 5 , according to the conventional LTE PDCCH (for convenience, conventional PDCCH or L-PDCCH) can be allocated to the control region of the subframe (see Figure 4). In the accompanying drawings, the L-PDCCH region means the region where the L-PDCCH can be allocated. At the same time, the PDCCH can be further allocated to the data region (e.g., the resource region for the PDSCH). The PDCCH allocated to the data region is called the E-PDCCH. As shown, the control channel resources can be further acquired through the E-PDCCH to alleviate the scheduling restrictions caused by the limited control channel resources of the L-PDCCH region. Similar to the L-PDCCH, the E-PDCCH carries the DCI. For example, the E-PDCCH can carry downlink scheduling information and uplink scheduling information. For example, the UE can receive the EPDCCH and receive data / control information via the PDSCH corresponding to the E-PDCCH. In addition, the UE can receive the E-PDCCH and send data / control information via the PUSCH corresponding to the E-PDCCH. Depending on the cell type, the E-PDCCH / PDSCH can be allocated starting from the first OFDM symbol of the subframe. In this specification, PDCCH includes both L-PDCCH and EPDCCH, unless otherwise specified.

[0093] Figure 6 The figure shows an uplink subframe structure used in LTE(-A).

[0094] refer to Figure 6 , subframe 500 includes two 0.5ms time slots 501. When using the normal CP length, each time slot includes 7 symbols 502, one symbol corresponding to one SC-FDMA symbol. Resource block 503 is a resource allocation unit corresponding to 12 subcarriers in the frequency domain and one time slot in the time domain. The uplink subframe structure of LTE (-A) is divided into a data region 504 and a control region 505. The data region refers to a communication resource used to send data such as audio, packets, etc. to the UE, and includes a PUSCH (physical uplink shared channel). The control region means a communication resource used to send UL control signals (e.g., DL channel quality reports from various UEs, ACK / NACK for reception of DL signals, UL scheduling requests, etc.), and includes a PUCCH (physical uplink control channel). The sounding reference signal (SRS) is sent by the SC-FDMA symbol at the last position on the time axis in a single subframe. The SRS of several UEs sent by the last SC-FDMA of the same subframe can be sorted according to the frequency position / sequence. The SRS is used to transmit a UL channel status to the BS, and may be periodically transmitted according to a subframe period / offset configured by an upper layer (eg, RRC layer), or aperiodically transmitted in response to a request of the BS.

[0095] Figure 7The SC-FDMA scheme and the OFDMA scheme are illustrated in the figure. The 3GPP system adopts OFDMA in downlink and uses SC-FDMA in uplink.

[0096] refer to Figure 7 , a UE for transmitting an uplink signal and a BS for transmitting a downlink signal both include a serial-to-parallel converter 401, a subcarrier mapper 403, an M-point IDFT module 404, and a cyclic prefix (CP) adding module 406. The UE for transmitting a signal according to SC-FDMA further includes an N-point DFT module 402. The N-point DFT module 402 enables the transmitted signal to have a single carrier characteristic by offsetting a partial IDFT processing effect of the M-point IDFT module 404.

[0097] Hereinafter, HARQ (Hybrid Automatic Repeat Request) is described. In a wireless communication system, when there are a plurality of UEs having data to be transmitted in UL / DL, a BS selects a UE to which data is to be transmitted in each TTI (Transmission Time Interval) (e.g., subframe). In a multi-carrier system or a system operating similarly thereto, a BS selects a UE to which data is to be transmitted in UL / DL, and also selects a frequency band for data transmission by the corresponding UE.

[0098] The following description is made with reference to UL. First, the UE sends a reference (or pilot) signal in the UL, and the BS obtains the channel state of the UE by using the reference signal sent by the UE, thereby selecting the UE that sends data in the UL on each unit frequency band in each TTI. The BS notifies the UE of such a result. That is, the BS sends a UL assignment message to the UE that is UL scheduled to a specific TTI, indicating that it uses a specific frequency band to send data. The UL assignment message may be referred to as a UL grant. The UE sends data in the UL according to the UL assignment message. The UL assignment message may include UE ID (UE identity), RB allocation information, MCS (modulation and coding scheme), RV (redundancy version), new data indicator (NDI), etc.

[0099] In the case of synchronous HARQ, the retransmission time (for example, after 4 subframes from the time of receiving NACK) is systematically agreed upon (synchronous HARQ). Therefore, the UL grant message sent by the BS to the UE can be sent only at the time of initial transmission, and the subsequent retransmission is performed through an ACK / NACK signal (for example, a PHICH signal). In the case of asynchronous HARQ, because the retransmission time is not mutually agreed upon, the BS should send a retransmission request message to the UE. In addition, in the case of non-adaptive HARQ, the frequency resources or MCS used for retransmission are the same as the frequency resources or MCS used for previous transmission. In the case of adaptive HARQ, the frequency resources or MCS used for retransmission may be different from the frequency resources or MCS used for previous transmission. For example, in the case of asynchronous adaptive HARQ, because the frequency resources or MCS used for retransmission changes at each transmission moment, the retransmission request message may include UEID, RB allocation information, HARQ process ID / number, RV, NDI information, etc.

[0100] Figure 8 The UL HARQ operation in the LTE / LTE-A system is exemplarily shown. In the LTE / LTE-A system, the UL HARQ uses synchronous non-adaptive HARQ. In the case of using 8-channel HARQ, the HARQ process numbers are given as 0 to 7. A single HARQ process operates in each TTI (eg, subframe). Figure 8 , BS 110 transmits a UL grant to UE 120 through PDCCH [S600]. After 4 subframes (e.g., subframe 4) from the time of receiving the UL grant (e.g., subframe 0), UE 120 transmits UL data to BS 110 using RB and MCS specified by the UL grant [S602]. BS 110 decodes the UL data received from UE 120 and then generates ACK / NACK. If the UL data fails to be decoded, BS 110 transmits NACK to UE 120 [S604]. UE 120 retransmits the UL data after 4 subframes from the time of receiving the NACK [S606]. The same HARQ processor is responsible for the initial transmission and retransmission of the UL data (e.g., HARQ process 4). ACK / NACK information may be transmitted through PHICH.

[0101] Meanwhile, the DL HARQ scheme in the LTE / LTE-A system uses asynchronous adaptive HARQ. Specifically, the base station 110 sends a DL grant to the UE 120 through the PDCCH. The UE 120 receives DL data from the BS 110 using the RB and MCS specified by the DL grant at the time of receiving the DL grant (e.g., subframe 0). The UE 120 decodes the DL data and then generates an ACK / NACK. If the DL data fails to be decoded, the UE 120 sends a NACK to the BS 110 after 4 subframes (e.g., subframe 4) from the time of receiving the DL data. Thereafter, the BS 110 sends a DL grant indicating the retransmission of the DL data to the UE 120 through the PDCCH at the desired time (e.g., subframe X). The UE 120 receives DL data from the BS 110 again using the RB and MCS specified by the DL grant at the time of receiving the DL grant (e.g., subframe X).

[0102] There are multiple parallel HARQ processes for DL / UL transmission in the BS / UE. Multiple parallel HARQ processes enable DL / UL transmission to be performed continuously while waiting for HARQ feedback of reception success or reception failure for the previous DL / UL transmission. Each HARQ process is associated with a HARQ buffer of the MAC (Media Access Control) layer. Each HARQ process manages state variables related to the transmission count of the MAC PDU (Physical Data Block) in the buffer, the HARQ feedback for the MAC PDU in the buffer, the current redundancy version, etc.

[0103] The HARQ process is responsible for reliable transmission of data, such as a transport block (TB). When channel coding is performed, the transport block can be divided into at least one code block (CB) by considering the size of the channel encoder. After channel coding, at least one or more code blocks are concatenated to configure a codeword (CW) corresponding to the transport block.

[0104] Fig. 9 The transport block (TB) processing procedure is exemplarily shown. Fig. 9 The process can be applied to the data of DL-SCH, PCH and MCH (multicast channel) transport channels. It is also possible to similarly process the UL TB (or the data of the UL transport channel).

[0105] refer to Fig. 9, the transmitter adds a CRC (e.g., 24 bits) (TB CRC) for error checking to the TB. Thereafter, the transmitter is able to segment (TB+CRC) into multiple code blocks by considering the size of the channel encoder. The maximum size of a code block in LTE / LTE-A is 6144 bits. Therefore, if the TB size is equal to or less than 6144 bits, no code block is configured. If the TB size is greater than 6144 bits, the TB is segmented in units of 6144 bits to configure multiple code blocks. A CRC (e.g., 24 bits) (CB CRC) is attached separately to each code block for error checking. The individual code blocks are channel coded and rate matched, and then concatenated into one to configure a codeword. In LTE / LTE-A, data scheduling and the corresponding HRAQ process are performed in units of TB, and the CB CRC is used to determine the early termination of TB decoding.

[0106] The HARQ process is associated with a soft buffer for transport blocks and a soft buffer for code blocks at the PHY (physical) layer. A soft buffer with a length (K) for the rth code block at the transmitting end is generated as follows w =3K Π )'s circular buffer.

[0107] [Formula 1]

[0108] - For k=0, ..., K Π -1

[0109] - For k=0, ..., K Π -1

[0110] - For k=0, ..., K Π -1

[0111] N IR The bit indicates the soft buffer size for the transport block, and N cb Indicates the soft buffer size for the rth code block. N cb See below, where C indicates the number of code blocks.

[0112] [Formula 2]

[0113] - DL-SCH and PCH transport channel situations

[0114] -N cb =K w UL-SCH and MCH transport channel situations

[0115] N IR It is expressed as follows.

[0116] [Formula 3]

[0117]

[0118] Here, N soft Indicates the total number of soft channel bits according to UE capabilities.

[0119] If N soft =35982720, then K C =5,

[0120] Otherwise, if N soft =3654144 and the UE can support a maximum of 2 spatial layers of the DL cell, then K C =2

[0121] Otherwise K C =1

[0122] Finish.

[0123] If the UE is configured to receive PDSCH transmissions based on transmission mode 3, 4, 8 or 9, K MIMO is 2, otherwise, K MIMO Yes 1.

[0124] M DL_HARQ is the maximum number of DL HARQ processes.

[0125] M limit Serves 8.

[0126] In FDD and TDD, the UE is configured to have two or more serving cells. For each serving cell, for at least K MIMO ·min(M DL_HARQ ,M limit ) transport blocks, if the decoding of the code block of the transport block fails, the UE at least stores the code block corresponding to The received soft channel bits in the range of n SB It is given by the following formula.

[0127] [Formula 4]

[0128]

[0129] w k , C, N cb , K MIMO , and M limit Same as those defined above.

[0130] M DL_HARQ is the maximum number of DL HARQ processes.

[0131] is the number of configured serving cells.

[0132] N′ soft is the total number of soft channel bits according to UE capabilities.

[0133] When determining k, the UE preferentially stores the soft channel bits corresponding to low k values. k Corresponds to the received soft channel bits. Range A subset that is not included in the received soft channel bits may be included.

[0134] Scheduling for UL transmission in LTE is enabled only when the UL transmission timing of the user equipment is synchronized. The random access procedure is used for various purposes. For example, the random access procedure is performed in the case of initial network access, handover, data generation, etc. In addition, the user equipment can obtain UL synchronization through the random access procedure. Once UL synchronization is obtained, the base station can allocate resources for UL transmission to the corresponding user equipment. The random access procedure can be classified into a contention-based procedure and a non-contention-based procedure.

[0135] Fig.10 is a diagram of an example of a contention-based random access procedure.

[0136] refer to Fig.10, the user equipment receives information about random access from the base station through system information. Thereafter, if random access is required, the user equipment sends a random access preamble (or message 1) to the base station (S710). Once the base station receives the random access preamble from the user equipment, the base station sends a random access response message (or message 2) to the user equipment (S720). Specifically, the DL scheduling information about the random access response message can be sent on the L1 / L2 control channel (PDCCH) by CRC masking with RA-RNTI (Random Access-RNTI). After receiving the DL scheduling signal masked by RA-RNTI, the user equipment receives a random access response message from the PDSCH, and is then able to decode the received random access response message. Subsequently, the user equipment confirms whether there is random access response information indicated to itself in the received random access response message. The existence of the random access response information indicated to itself can be confirmed by confirming whether there is a RAID (Random Access Preamble ID) for the preamble that the user equipment has sent. The random access response information may include a timing advance (TA) indicating timing offset information for synchronization, radio resource allocation information used in UL, a temporary identifier (e.g., T-RNTI) for user equipment (UE) identification, etc. Upon receiving the random access response information, the user equipment transmits a UL message (or message 3) on a UL SCH (uplink shared channel) according to the radio resource allocation information included in the received random access response information (S730). After receiving the UL message from the user equipment in step S730, the base station transmits a contention resolution message (or message 4) to the user equipment (S740).

[0137] Fig.11 1 is a diagram of an example of a non-contention based random access procedure. The non-contention based random access procedure can be used in a handover procedure, or exists when requested by a command given by a base station. The basic procedure is the same as the contention based random access procedure.

[0138] refer to Fig.11 , the user equipment receives an assignment of a random access preamble used only for itself (i.e., a dedicated random access preamble) from the base station (S810). Dedicated random access preamble indication information (e.g., preamble index) may be included in a handover command message or may be received through a PDCCH. The user equipment sends the dedicated random access preamble to the base station (S820). Thereafter, the user equipment receives a random access response from the base station (S830), and the random access procedure ends.

[0139] In order to initiate a non-contention-based random access procedure with a PDCCH command, DCI format 1A is used. In addition, DCI format 1A can also be used for compact scheduling of one PDSCH codeword. The following information is sent using DCI format 1A.

[0140] - Flag for distinguishing DCI format 0 or DCI format 1A: 1 bit. A flag value of "0" indicates DCI format 0, and a flag value of "1" indicates DCI format 1A.

[0141] In a case where all remaining fields after scrambling the CRC of DCI format 1A with C-RNTI are set as follows, DCI format 1A may be used for a random access procedure according to a PDCCH command.

[0142] - Centralized / distributed VRB (virtual resource block) assignment flag: 1 bit. This flag is set to 0.

[0143] - Resource block assignment information: bits. Each bit is set to 1.

[0144] - Preamble index: 6 bits

[0145] -PRACH masking index: 4 bits

[0146] - All remaining bits for compact scheduling of PDSCH in DCI format 1A are set to 0.

[0147] Fig.12 The diagram shows a carrier aggregation (CA) communication system.

[0148] refer to Fig.12 , multiple UL / DL component carriers (CCs) can be aggregated to support a wider UL / DL bandwidth. CCs can be adjacent or non-adjacent in the frequency domain. The bandwidth of a CC can be determined independently. Asymmetric CA in which the number of UL CCs is different from the number of DL CCs can also be implemented. On the other hand, it can be set to send / receive control information only through a specific CC. The specific CC can be called a primary CC and the other CCs can be called secondary CCs. For example, when cross-carrier scheduling (or cross-CC scheduling) is applied, the PDCCH for downlink allocation can be sent on DL CC#0 and the corresponding PDSCH can be sent on DL CC#2. The term "component carrier" can be replaced by other equivalent terms (for example, "carrier", "cell", etc.).

[0149] For cross-CC scheduling, a carrier indicator field (CIF) is used. The presence or absence of CIF in PDCCH can be determined semi-statically and UE-specifically (or UE group-specifically) through higher layer signaling (eg, RRC signaling). The basic matters of PDCCH transmission are summarized as follows.

[0150] ■ CIF disabled: PDCCH on a DL CC is used to allocate PDSCH resources on the same DL CC or PUSCH resources on a single linked UL CC.

[0151] No CIF

[0152] ■ CIF enabled: A PDCCH on a DL CC can be used to allocate PDSCH or PUSCH resources on one DL / UL CC among multiple aggregated DL / UL CCs using CIF.

[0153] ● Extended to have LTE DCI format with CIF

[0154] - CIF corresponds to a fixed x-bit field (e.g., x=3) (when CIF is set)

[0155] -CIF position is fixed regardless of DCI format size (when CIF is set)

[0156] When CIF exists, the BS can allocate monitoring DL CC (set) to reduce the BD complexity of the UE. For PDSCH / PUSCH scheduling, the UE can detect / decode PDCCH only on the corresponding DL CC. In addition, the BS can send PDCCH only through the monitoring DL CC (set). The monitoring DL CC set can be set UE-specifically, UE group-specifically, or cell-specifically.

[0157] Fig.13 The diagram shows scheduling when multiple carriers are aggregated. Assume that 3 DL CCs are aggregated. Assume that DL CC A is set as a PDCCH CC. DL CC A, DL CC B, and DL CC C can be referred to as serving CCs, serving carriers, serving cells, etc. When CIF is disabled, each DL CC can only send a PDCCH that schedules its own PDSCH without CIF according to the LTE PDCCH rules (non-cross-CC scheduling). Conversely, when CIF is enabled according to UE-specific (or UE group-specific or cell-specific) high-layer signaling, a specific CC (e.g., DL CC A) can use CIF to send not only a PDCCH that schedules the PDSCH corresponding to DL CC A, but also a PDCCH that can schedule the PDSCH of other CCs (cross-CC scheduling). On the other hand, DL CC B and DL CC C do not send PDCCH.

[0158] At the same time, because millimeter waves (mmW) have short-wavelength signals, multiple antennas can be installed in the same area. For example, because the wavelength on the 30GHz band is 1cm, a total of 100 antenna elements can be installed in a two-dimensional array with an interval of 0.5λ (wavelength) on a 5*5cm panel. Therefore, in mmW systems, multiple antenna elements are used to increase coverage or increase throughput by improving beamforming (BF) gain.

[0159] In this regard, if a TXRU (transceiver unit) is provided for each antenna element to achieve transmission power and phase adjustment of each antenna element, independent beamforming can be performed for each frequency resource. However, in terms of price, installing a TXRU at each of the 100 antenna elements reduces efficiency. Therefore, a method of mapping multiple antenna elements to a single TXRU and adjusting the beam direction with an analog phase shifter is considered. Because this analog beamforming scheme is only capable of forming a single beam direction over the entire frequency band, it is disadvantageous that a frequency selective beam cannot be provided. A hybrid BF in an intermediate form between digital BF and analog BF can be considered, which has B TXRUs that are less than Q antenna elements. In this case, although there are differences depending on the connection scheme between the B TXRUs and the Q antenna elements, the number of directions of beams that can be transmitted simultaneously is limited to be equal to or less than B.

[0160] Fig.14 The analog beamforming is shown as an example. Fig.14 , a transmitter can transmit a signal by changing the direction of a beam according to time [transmit (Tx) beamforming], and a receiver can also receive a signal by changing the direction of a beam according to time [receive (Rx) beamforming]. In a predetermined time interval, (i) the Tx beam and the Rx beam simultaneously change the beam directions according to time, (ii) the direction of the Rx beam is changed according to time while the Tx beam is fixed, or (iii) the direction of the Tx beam is changed according to time while the Rx beam is fixed.

[0161] Meanwhile, in the next generation RAT (Radio Access Technology), a self-contained subframe is considered to minimize a data transmission delay. Fig.15 The structure of a self-contained subframe is shown as an example. Fig.15 In the figure, the shaded area indicates the DL control area, and the black part indicates the UL control area. The unmarked area can be used for DL ​​or UL data transmission. Because DL transmission and UL transmission are performed sequentially in a single subframe, DL data can be sent and UL ACK / NACK can be received in the subframe. Because the time spent on data retransmission is reduced in the event of a data transmission error, the delivery delay of the final data can be minimized.

[0162] As examples of configurable / settable self-contained subframe types, at least the following four subframe types can be considered: The intervals are listed in chronological order.

[0163] -DL control interval + DL data interval + GP (guard period) + UL control interval

[0164] -DL control interval + DL data interval

[0165] -DL control interval + GP + UL data interval + UL control interval

[0166] -DL control interval + GP + UL data interval

[0167] In the DL control interval, PDFICH, PHICH and PDCCH can be transmitted, and in the DL data interval, PDSCH can be transmitted. In the UL control interval, PUCCH can be transmitted, and in the UL data interval, PUSCH can be transmitted. GP provides a time interval in the process of BS and UE switching from Tx mode to Rx mode or from Rx mode to Tx mode. Some OFDM symbols at the moment of switching from DL to UL in a subframe can be set to GP.

[0168] Example

[0169] In the case of the existing LTE system, if the size of DL data (ie, TBS) becomes equal to or greater than a predetermined level, a bit stream (ie, TB) to be transmitted through a PDSCH is segmented into a plurality of CBs, and channel coding and CRC are applied per CB [see Fig. 9 ]. If the UE fails to receive (i.e., decode) any one of the multiple CBs included in a single TB, the UE reports the HARQ-ACK feedback corresponding to the TB to the BS as NACK. By doing so, the BS retransmits all CBs corresponding to the TB. That is, based on the scheduling / transmission in TB units from the BS and the HARQ-ACK feedback configuration in TB units from the UE corresponding thereto, the HARQ operation of the DL data in the existing LTE / LTE-A is performed.

[0170] Meanwhile, the next generation RAT (hereinafter referred to as the new RAT) system is basically capable of having a wider system (carrier) BW (bandwidth) than LTE, so that the TBS (or maximum TBS) is highly likely to become larger than that of LTE. Therefore, the number of CBs configuring a single TB may become larger than that in LTE. Therefore, if HARQ-ACK feedback in units of TB is performed in the new RAT system as in the existing system, even in the case where a decoding error (ie, NACK) is generated only for a few CBs, it is accompanied by retransmission scheduling in units of TB, and therefore, resource utilization efficiency may be reduced. Moreover, in the new RAT system, by allocating some (symbols) of the resources for sending a delay-insensitive data type 1 (eg, enhanced mobile broadband (eMBB)) with a large time interval (TTI), a delay-sensitive data type 2 (eg, ultra-reliable low latency communication (URLLC)) with a small TTI can be transmitted in a punctured data type 1 manner. By including such an operation, a decoding error (ie, NACK) concentrated on a specific portion of multiple CBs configuring a single TB may occur for data type 1 due to the influence of an interference signal having a time-selective characteristic.

[0171] In view of the properties of the new RAT system, the present invention proposes a method for performing (retransmission) scheduling in units of CB or CBG (CB group) and configuring / sending HARQ-ACK feedback in units of CB / CBG. In detail, the present invention proposes a method for configuring CBG, a method for configuring HARQ-ACK (hereinafter referred to as A / N) feedback, a method for operating a receiving soft buffer of a UE, a method for handling a specific mismatch situation, etc.

[0172] For the sake of clarity, the methods proposed in the present invention are categorized into various embodiments, but for the convenience of description, these embodiments may be used in combination.

[0173] First, abbreviations / terms used in the present invention are described as follows.

[0174] -TBS: TB size. Configure the total number of bits in a TB

[0175] -CB: Code Block

[0176] -CB size: the total number of bits in the configuration CB

[0177] -CBG: Code Block Group. All CBs (configuring a single TB) may be configured as a single CBG, or some of a plurality of CBs may be configured as a single CBG, or each CB may be configured as a single CBG.

[0178] -A / N: HARQ-ACK response. That is, this can mean ACK, NACK, or DTX. DTX indicates the case of missing PDCCH. In the case of ACK, the A / N bit can be set to 1, and in the case of NACK, the A / N bit can be set to 0. This can be used equivalent to HARQ-ACK or ACK / NACK.

[0179] -A / N based on CBG: CRC is not attached to CBG, so A / N for CBG can be generated based on the error check result of CB in CBG. For example, if all CBs in CBG are successfully detected, the UE sets the A / N response (or A / N bit) for CBG to ACK, and if any CB in CBG is not successfully detected, the UE can set the A / N response (or A / N bit) of CBG to NACK [logical AND]. The A / N payload of CBG of TB includes multiple A / N (response) bits, and each A / N (response) bit corresponds 1:1 to CBG of TB.

[0180] -CBG-based retransmission: In response to the CBG-based A / N, TB retransmission can be performed in units of CBGs. For example, in the case of retransmitting a TB to a UE, the BS can perform retransmission only for CBGs for which NACK is received from the UE. In so doing, in the case where the retransmission of a TB corresponds to the same HARQ process as the previous transmission of the TB, the CBs in the CBG remain the same as in the case of the initial transmission of the TB.

[0181] -CBG size: the number of CBs to configure CBG

[0182] -CBG index: An index used to identify a CBG. Depending on the context, a CBG index can be equivalently used as a CBG with a corresponding index.

[0183] - Symbol: This may mean an OFDMA symbol or an SC-FDMA symbol unless distinguished separately.

[0184] -floor(X): descending function. This means the largest integer equal to or less than X.

[0185] -ceiling(X): Climbing function. This means the smallest integer equal to or greater than X.

[0186] -mod(A,B): This means the remainder when A is divided by B.

[0187] (X) Methods for configuring CB

[0188] 1) Method X-1: The number of bits "Cn" for configuring a single CB is given, and Cm CBs are configured based on the number of bits "Cn".

[0189] The number of bits Cn for configuring a single CB may be predefined as a single identical value independent of the TBS, or as a different value per TBS (e.g., a value proportional to the TBS), or the number of bits may be indicated to the UE via semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI). Thus, when the total number of bits for configuring a TB is Ck, it is possible to configure CBs whose number is Cm=floor(Ck / Cn) or Cm=ceiling(Ck / Cn). In the former case, only one CB may be configured with (Cn+mod(Ck,Cn)) bits, and each of the remaining (Cm-1) CBs may be configured with Cn bits. In the latter case, only one CB may be configured with mod(Ck,Cn) bits, and each of the remaining (Cm-1) CBs may be configured with Cn bits. In the former case, Cn may mean the minimum number of bits for configuring a CB, and in the latter case, Cn may mean the maximum number of bits for configuring a CB.

[0190] As another method, a method of uniformly distributing the number of bits per CB to all CBs can be applied. Taking the aforementioned case as an example, when Cm=floor(Ck / Cn) CBs are configured, mod(Ck,Cn) CBs can be configured with (Cn+1) bits, and the remaining CBs can be configured with Cn bits. Moreover, when Cm=ceiling(Ck / Cn) CBs are configured, (Cn-mod(Ck,Cn)) CBs can be configured with (Cn-1) bits, and the remaining CBs can be configured with Cn bits. In the former case, Cn may mean the minimum number of bits to configure a CB, and in the latter case, Cn may mean the maximum number of bits to configure a CB.

[0191] At the same time, if the above method is applied, at least one specific CB (hereinafter referred to as a small CB) among the total number of Cm CBs can be configured with a small number of bits less than the remaining other CBs (hereinafter referred to as regular CBs). Therefore, it may be necessary to group Cm CBs of unequal sizes into a scheme of multiple CBGs of M. Specifically, there may be a situation where the total number of CBs "Cm" becomes a multiple of the number of CBGs "M" and a situation where the total number of CBs "Cm" does not become a multiple of the number of CBGs "M". For each situation, the following CB grouping scheme can be considered. In the following, the CBG size may mean the number of CBs per CBG. At the same time, if Cm is not a multiple of M, the size of each CBG may be different, and the size difference between CBGs may be limited to a maximum of 1 CB.

[0192] A. When Cm is a multiple of M (all CBGs are of equal size)

[0193] - Option 1-1: Small CBs are configured to maximize distribution to all CBGs

[0194] -Option 1-2: Small CB is configured to be the largest part of the minority CBG

[0195] B. Case where Cm is not a multiple of M (the size of each CBG can be different)

[0196] - Option 2-1: Small CBs are configured to belong to large CBGs as much as possible

[0197] - Option 2-2: Small CBs are configured to belong to the smallest CBG possible

[0198] - Option 2-3: Apply Option 1-1 or Option 1-2

[0199] For example, when Cm=7 and CB indexes 1 / 2 / 3 / 4 / 5 / 6 / 7 are respectively configured with 5 / 5 / 5 / 5 / 5 / 5 / 2 bits, M=3 CBG configurations can be considered. Here, if option 2-1 is applied, CB indexes {1,2}, {3,4} and {5,6,7} can be configured as CBG indexes 1 / 2 / 3, respectively. If option 2-2 is applied, CB indexes {1,2,3}, {4,5} and {6,7} can be configured as CBG indexes 1 / 2 / 3, respectively. For another example, when Cm=7 and CB indexes 1 / 2 / 3 / 4 / 5 / 6 / 7 are respectively configured with 5 / 5 / 5 / 5 / 4 / 4 / 4 bits, M=3 CBG configurations can be considered. Here, if option 2-1 is applied, CB indexes {1,2}, {3,4} and {5,6,7} can be configured as CBG indexes 1 / 2 / 3, respectively. If option 2-2 is applied, CB indexes {1,2,3}, {4,5} and {6,7} can be configured as CBG indexes 1 / 2 / 3, respectively. On the other hand, if option 1-1 is applied, CB indexes {1,2,5}, {3,6} and {4,7} can be configured as CBG indexes 1 / 2 / 3, respectively, and if option 1-2 is applied, CB indexes {1,2}, {3,4} and {5,6,7} can be configured as CBG indexes 1 / 2 / 3, respectively.

[0200] Additionally, by configuring the CBGs corresponding to the parts with potentially low decoding reliability to include as small CBs as possible, the size of the CBGs with a high retransmission probability can be minimized. For example, the cases with potentially low decoding reliability may include the cases where the CB size of the radio signal is relatively small, the radio signal is far from the DMRS on the time axis, the radio signal is far from the CSI feedback timing, or the radio signal is mapped to the (OFDMA / SC-FDMA) symbols adjacent to the SRS (or PUCCH, PRACH). For this purpose, the CBGs can be configured as follows.

[0201] a) Configure the regular CBs in units of X bits starting from the low CB index, and then configure the small CBs in units of Y bits (Y < X) starting from a specific CB index.

[0202] b) Bundle and configure the regular CBs in units of M CBs starting from the low CBG index (sequentially starting from the CBs with the low CB index), and then configure the small CBs in units of K CBs (K < M) starting from a specific CBG index. Here, as proposed in the previous description, the size difference between CBGs can be limited to a maximum of 1 CB (e.g., M = K + 1). According to a) and b), compared with the CBGs with higher indices, the CBGs with lower indices can have a relatively smaller CBG size, and even if the CBG sizes are the same, they can include more small CBs.

[0203] c) Map the signals sequentially in a frequency-first (or time-first) scheme starting from the CBGs with the low CBG index. Here, compared with the CBGs with higher indices, the CBGs with lower indices can be mapped to the resources with relatively higher decoding reliability.

[0204] Meanwhile, in the case of "Cn > Ck", all the bits of the TB are configured as a single CB, and one CB including Ck bits can be configured.

[0205] 2) Method X-2: Given the total number of CBs "Cm", each CB is configured in units of Cn bits based on this Cm.

[0206] The total number of CBs "Cm" can be predefined as the same single value regardless of the TBS, or as a different value per TBS (e.g., a value proportional to the TBS), or the total number of CBs can be indicated to the UE via semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI). For example, if the total number of bits for configuring TBs is Ck, each CB can be configured in units of Cn=floor(Ck / Cm) bits or Cn=ceiling(Ck / Cm) bits. In the former case, only one CB can be configured with (Cn+mod(Ck,Cn)) bits, and each of the remaining (Cm-1) CBs can be configured with Cn bits. In the latter case, only one CB can be configured with mod(Ck,Cn) bits, and each of the remaining (Cm-1) CBs can be configured with Cn bits. In the former case, Cn may mean the minimum number of bits to configure a CB, and in the latter case, Cn may mean the maximum number of bits to configure a CB.

[0207] As another method, a scheme of uniformly distributing the number of bits per CB to all CBs can be applied. Taking the aforementioned case as an example, if the CB is configured in units of Cn=floor(Ck / Cm) bits, then mod(Ck,Cm) CBs are configured with (Cn+1) (or, ceiling(Ck / Cm)) bits, and the remaining (Cm-mod(Ck,Cm)) CBs can be configured with Cn bits. If the CB is configured in units of Cn=ceiling(Ck / Cm) bits, then (Cm-mod(Ck,Cm)) CBs are configured with (Cn-1) (or, floor(Ck / Cm)) bits, and the remaining mod(Ck,Cm) CBs can be configured with Cn bits. In the former case, Cn may mean the minimum number of bits to configure a CB, and in the latter case, Cn may mean the maximum number of bits to configure a CB.

[0208] 3) Method X-3: The minimum number of bits "Tm" for configuring a CB is given, and the CB is configured based on the Tm.

[0209] Each CB configuring one TB may be set to be configured with at least Tm bits. For example, if the TBS is assumed to be Ck, the maximum Cm value "Cm.max" satisfying the relationship "Ck / Cm≥Tm" is calculated, and the operation of segmenting the corresponding TB into Cm.max CBs can be considered.

[0210] 4) Method X-4: If the number of CBs is equal to or greater than a certain level, CB unit scheduling and grouping among a plurality of CBs are performed.

[0211] The scheduling of CB units or CBG units (retransmission) can only be set / defined to apply to the corresponding TB when the total number of CBs “K” configured for a TB is equal to or greater than Ts. Moreover, if the total number of CBs “K” is equal to or greater than Tg, multiple CBs can be set / defined to be grouped to configure a CBG (e.g., Ts < Tg). Here, the number of bits Cn for configuring a CB can be predefined or given by specific signaling (e.g., RRC signaling, DCI).

[0212] (A) Method for configuring CBG

[0213] 1) Method A-1: Give the number of CBs “N” for configuring a single CBG, and M CBGs are configured based on this number of CBs “N”.

[0214] The number of CBs “N” for configuring a single CBG can be predefined as a single same value independent of TBS, or a different value for each TBS (e.g., a value proportional to TBS), or this number of CBs can be indicated to the UE by semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI). For example, when the total number of CBs for configuring a TB is K, M = floor(K / N) or M = ceiling(K / N) CBGs can be configured. In the former case, only one CBG can be configured with (N + mod(K,N)) CBs, and each of the remaining (M - 1) CBGs can be configured with N CBs. In the latter case, only one CBG can be configured with mod(K,N) CBs, and each of the remaining (M - 1) CBGs can be configured with N CBs. In the former case, N can mean the minimum number of CBs for configuring a CBG, and in the latter case, N can mean the maximum number of CBs for configuring a CBG. Meanwhile, the UE can configure and send A / N bits per CBG.

[0215] As another method, a method of evenly distributing the number of CBs per CBG to all CBGs can be applied. Taking the aforementioned case as an example, in the case of configuring M = floor(K / N) CBGs, mod(K,N) CBGs can be configured with (N + 1) CBs, and the remaining CBGs can be configured with N CBs. Moreover, in the case of configuring M = ceiling(K / N) CBGs, (N - mod(K,N)) CBGs can be configured with (N - 1) CBs, and the remaining CBGs can be configured with N CBs. In the former case, N can mean the minimum number of CBs for configuring a CBG, and in the latter case, N can mean the maximum number of CBs for configuring a CBG.

[0216] Meanwhile, if N > K, all CBs for configuring the TB belong to a single CBG, and one CBG including K CBs can be configured.

[0217] 2) Method A-2: Given a total number of CBGs “M”, each CBG is configured in units of N CBs based on M.

[0218] The total number of CBGs "M" may be predefined as the same single value regardless of the TBS, or as a different value per TBS (e.g., a value proportional to the TBS), or the total number of CBGs may be indicated to the UE via semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI). The UE is able to identify / configure CBGs from the CBs of the TB based on the total number of CBGs "M". For example, if the total number of CBs configuring the TB is K, each CBG may be configured in units of N = floor (K / M) or N = ceiling (K / M) CBs. In the former case, only one CBG may be configured with (N + mod (K, N)) CBs, and each of the remaining (M-1) CBGs may be configured with N CBs. In the latter case, only one CBG may be configured with mod (K, N) CBs, and the remaining (M-1) CBGs may be configured with N CBs, respectively. In the former case, N may mean the minimum number of CBs to configure one CBG, and in the latter case, N may mean the maximum number of CBs to configure one CBG. Meanwhile, the UE can configure and send A / N bits per CBG. For example, the UE can configure M A / N bits for a TB, and each of these A / N bits can indicate the A / N result of the corresponding CBG.

[0219] As another method, a scheme of uniformly distributing the number of CBs per CBG to all CBGs can be applied. Taking the aforementioned case as an example, in the case where CBGs are configured in units of N=floor(K / M) CBs, mod(K,M) CBGs are configured with (N+1) (or, ceiling(K / M)) CBs, and the remaining (M-mod(K,M)) CBGs can be configured with N (or floor(K / M)) CBs. In addition, in the case where CBGs are configured in units of N=ceiling(K / M) CBs, (M-mod(K,M)) CBGs can be configured with (N-1) (or, floor(K / M)) CBs, and the remaining mod(K,M) CBGs can be configured with N (or, ceiling(K / M)) CBs. In the former case, N may mean the minimum number of CBs for configuring a CBG, and in the latter case, N may mean the maximum number of CBs for configuring a CBG.

[0220] Meanwhile, if M>K, each CB becomes a CBG, and a total number of K CBGs can be configured. In this case, it is possible to consider solution 1): when all A / N feedbacks are configured with M bits, (MK) bits that do not correspond to the actual CBG are processed as NACK or DTX, or solution 2): the A / N feedback itself is only configured with K bits corresponding to the actual CBG.

[0221] Fig.16 The signal transmission process according to the present invention is shown.

[0222] Reference Fig.16 , the UE can receive information about the number M of code block groups per transport block from the BS through upper layer signaling (e.g., RRC signaling) [S1602]. Thereafter, the UE can receive initial data transmission from the BS (through PDSCH) [S1604]. Here, the data includes a transport block, the transport block includes a plurality of code blocks, and the plurality of code blocks can be grouped into one or more code block groups. Here, some of the code block groups can include ceiling (K / M) code blocks, and the remaining code block groups can include flooring (K / M) code blocks. K indicates the number of code blocks in the data. Thereafter, the UE can feed back CBG-based A / N information about the data to the BS [S1606], and the BS can perform data retransmission based on the code block group [S1608]. The A / N information can be sent through the PUCCH or PUSCH. Here, the A / N information includes a plurality of A / N bits of the data, and each A / N bit can indicate each A / N response generated in units of code block groups of the data. The payload size of the A / N information can be kept the same based on M regardless of the number of code block groups configuring the data.

[0223] 3) Method A-3: CBG configuration based on a tree structure (or nested structure) for CBG number "M" and CBG size "N"

[0224] CBG can be configured to have a tree structure for the total number of CBGs “M” (e.g., M1, M2...) and the CBG size “N” (e.g., N1, N2...). In this case, multiple different CBG configurations based on multiple different (M, N) combinations can be set for one TB (size). For different (M, N) combinations, considering the CBG configurations in the cases of (M1, N1) and (M2, N2), if M1 < M2, then it can be set that N1 > N2. Moreover, one CBG in the case of (M1, N1) can be configured to include at least one CBG in the case of (M2, N2). Conversely, one CBG in the case of (M2, N2) can be configured to belong only to a specific CBG in the case of (M1, N1). Also, M2 can be set as a multiple of M1, or / and N1 can be set as a multiple of N2. M can be set to 2 m (m = 0, 1...). Meanwhile, an index regarding M, N, or the (M, N) combination, or one (or more) of the available CBG indices with reference to all (M, N) combinations can be indicated to the UE through semi-static signaling (e.g., RRC) or dynamic signaling (e.g., DCI). The UE can configure and transmit A / N bits for each CBG configured to correspond to the respective index. M and N can be predefined as the same single value independent of the TBS, or different values for each TBS (e.g., values proportional to the TBS).

[0225] For example, assuming that the total number of CBs configuring the TB is K = 16 and each CB is indexed as k = 0, 1...15, a scheme [Nested CBG Example 1] can be considered where the number of CBGs is set to M = {1, 2, 4, 8, 16} and the size of each corresponding CBG is set to N = K / M = {16, 8, 4, 2, 1}.

[0226] a) If (M, N) = (1, 16), then only 1 CBG is configured, and the corresponding CBG includes all 16 CBs.

[0227] b) If (M, N) = (2, 8), then 2 CBGs are configured, and each CBG includes 8 different CBs. In this case, one CBG includes 2 CBGs in the case of (M, N) = (4, 4).

[0228] c) If (M, N) = (4, 4), then 4 CBGs are configured, and each CBG includes 4 different CBs. In this case, one CBG includes 2 CBGs in the case of (M, N) = (8, 2).

[0229] d) If (M, N) = (8, 2), then configure 8 CBGs, and each CBG includes 2 distinct CBs from each other.

[0230] e) If (M, N) = (16, 1), then configure 16 CBGs, and each CBG includes only 1 distinct CB from each other.

[0231] In the state where multiple distinct (M, N) combinations and the number / size of CBGs according to them are pre-configured / specified as above, it is possible to indicate to the UE an index of a specific M, a specific N, or an (M, N) combination, or one (or more) of the available CBG indices with reference to all (M, N) combinations. In the above example, corresponding to the following cases, a total of 5 types of available M, N, or (M, N) combinations are set, and a total of 31 types of available CBG indices for all (M, N) combinations (corresponding to the sum of the available M values {1, 2, 4, 8, 16}) are set. The UE can perform decoding and corresponding A / N feedback configuration / transmission assuming the state of the CBG configuration corresponding to the M index and / or N index for the scheduled DL data (e.g., TB or CBG).

[0232] By generalizing this method, for the CBS configuration in the cases of (M1, N1) and (M2, N2) corresponding to different (M, N) combinations, it is possible to set multiple CBG configurations for one TB (size) only under the condition that if M1 < M2, then N1 ≥ N2. For example, assuming that the total number of CBs configuring the TB is K = 6, in the state where each CB is indexed with k = 0, 1... 5, it is possible to consider a scheme of setting the number of CBGs as M = {1, 2, 3, 6} and setting the size of each CBG corresponding to the number of CBGs as N = K / M = {6, 3, 2, 1} [Nested CBG Example 2].

[0233] a) If (M, N) = (1, 6), then configure only 1 CBG, and the corresponding CBG includes all 6 CBs.

[0234] b) If (M, N) = (2, 3), then configure 2 CBGs, and each CGB includes 3 distinct CBs from each other. For example, the CB index sets {0, 1, 2} and {3, 4, 5} are each configured with 1 CGB.

[0235] c) If (M, N) = (3, 2), then configure 3 CBGs, and each CGB includes 2 distinct CBs from each other. For example, the CB index sets {0, 1}, {2, 3}, and {4, 5} are each configured with 1 CBG.

[0236] d) If (M, N) = (6, 1), then configure 6 CBGs, and each CBG includes only 1 distinct CB from each other.

[0237] For another example, assuming that the total number of CBs configuring a TB is K=9, when each CB is indexed with k=0, 1...8, it is possible to consider setting the number of CBGs to M={1, 2, 3, 6} and setting the CBG size corresponding to each number of CBGs to N={9, (5 or 4), 3, (2 or 1)} [Nested CBG Example 3].

[0238] a) If (M, N) = (1, 16), only 1 CBG is configured, and the corresponding CBG includes all 9 CBs.

[0239] b) If (M, N) = (2, 5 or 4), a total of 2 CBGs are configured, one CBG includes 5 CBs, and the other CBG includes 4 CBs. For example, CB index sets {0, 1, 2, 3, 4} and {5, 6, 7, 8} configure one CBG respectively.

[0240] c) If (M, N) = (3, 3), 3 CBGs are configured, and each CBG includes 3 different CBs. For example, CB index sets {0, 1, 2}, {3, 4, 5}, and {6, 7, 8} are configured with one CBG respectively.

[0241] d) If (M, N) = (6, 2 or 1), a total of 6 CBGs are configured. Each of 3 CBGs among the 6 CBGs includes 2 CBs, and each of the other 3 CBGs includes 1 CB. For example, CB index sets {0, 1}, {2, 3}, {4, 5}, {6}, {7}, and {8} configure one CGB respectively.

[0242] In the case of nested CBG Example 2 / Example 3, a total of 12 (=1+2+3+6) CBGs configured can be indexed (based on 4 different (M, N) combinations). Based on this, the BS indicates the CBG scheduled for retransmission (via DCI), and / or the UE can configure and send A / N feedback for the indicated CBG.

[0243] At the same time, by considering the DCI overhead used for scheduling target CBG indication and / or the UCI overhead used for corresponding A / N feedback configuration, the total number L of CBG indexes configured in a nested form can be set equally per TBS, or the L value per TBS can be set so that the bit overhead used for CBG indication per TBS is equal (for example, so that the value of ceiling(log2(L)) is equal).

[0244] 4) Method A-4: CBs belonging to a specific number of symbol sets (and a specific number of RB sets) are configured as one CBG

[0245] In a state where the time interval (and / or frequency interval) for transmitting the TB is partitioned into multiple symbol sets (hereinafter referred to as symbol groups (SGs)) (and / or multiple RB sets (hereinafter referred to as RB groups (RBGs)), the CB transmitted through each SG (and / or each RBG) may be configured as one CBG. In this case, information about the number of symbols in each SG or the number of symbols configuring a single SG (and / or the number of RBs in each RBG or the number of RBs configuring a single RBG) may be indicated to the UE through semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI). In the case of receiving DL data, the UE is able to configure and transmit the A / N bits per CBG.

[0246] Moreover, for the number of symbols configuring an SG or the total number of SGs configured within a TB transmission time interval (and / or the number of RBs configuring an RBG or the total number of RBGs configured within a TB transmission frequency interval), it is also feasible to configure the CBG to have a tree structure as in method A-3. On the basis of the nested CBG examples 1 / 2 / 3, for example, assuming that the total number of symbols (or the number of RBs) configuring the TB is K=16, 6, or 9, each symbol (or RB) can be indexed as k=0~15, k=0~5, or k=0~8. In this state, multiple SGs (or RBGs) having a nested structural relationship with each other can be configured in a form similar to the nested CBG examples 1 / 2 / 3. Moreover, the size / number of SGs (and / or RBGs) can be predefined as the same single value independent of the TBS, or predefined as a different value per TB (e.g., a value proportional to the TBS).

[0247] Meanwhile, if a CB is mapped / sent across multiple SGs (and / or RBGs), the corresponding CB may be defined as: Option 1) being included in the CBG corresponding to the SG with the lowest or highest symbol index (and / or the RBG with the lowest or highest RB index); or Option 2) being included in the CBG corresponding to the SG (and / or RBG) that includes the most coded bits of the corresponding CB.

[0248] As another method, in terms of CBG configuration / indication for (retransmission) scheduling in the BS, if one CB is mapped / sent across multiple SGs (and / or RBGs), the corresponding CB can be set to be included in all multiple CBGs corresponding to the corresponding multiple SGs (or RGBs). On the other hand, in terms of A / N feedback configuration per CBG in the UE, in a state where the corresponding CB is included only in the CBG corresponding to a specific one of the corresponding multiple SGs (or RBGs), the UE can operate to configure and send A / N bits per CBG. In this case, the UE (in the case of A / N feedback configuration) can select a specific one CBG including the corresponding CB as follows.

[0249] 1) When the decoding result of the corresponding CB is NACK (in terms of scheduling, among all multiple CBGs including the corresponding CB), if there is a CBG including a CB with NACK even if the corresponding CB is excluded, one of such CBGs is selected (based on option 1 / 2 application). If there is no such CBG, one of all multiple CBGs (including the corresponding CB in terms of scheduling) can be selected (based on option 1 / 2 application).

[0250] 2) When the decoding result of the corresponding CB is ACK, it is also possible to select one of all multiple CBGs (including the corresponding CB in terms of scheduling) (based on option 1 / 2 application).

[0251] Meanwhile, if multiple CBGs including the same CB are scheduled at the same time, the corresponding CB can be operated to be transmitted only once. For example, the corresponding CB can be transmitted in a manner of being included in only a specific one of the corresponding multiple CBGs (based on option 1 / 2 application).

[0252] By generalizing the above scheme, the proposed scheme can be applied to the following situations, in terms of CBG configuration / indication for BS scheduling, one CB is set to be commonly included in multiple CBGs, and in terms of UE configuring A / N feedback per CBG, operation is performed so that the corresponding CB can be included only in a specific one of the multiple CBGs. For example, when a total number of K CBs are configured as M CBGs, all CBGs can be set to equally include N (=ceiling(K / M)) CBs, which are counted as the number of CBs per CBG. In this case, some of the M CBGs can be set to include a common specific CB. For example, two random CBGs in a CBG set with a number less than M can include a common CB, and the number of CBs included in the two random CBGs can be a total of (M-mod(K,M)).

[0253] As another solution, in order to prevent a CB from being mapped / sent across multiple SGs (and / or RBGs) or to make the number of data bits belonging to each CBG match each other as equally as possible, the following method can be considered. Assuming that the scheduled TBS is A bits, and assuming that the number of SGs or RBGs (generalized as CBGs) allocated to the corresponding TBS is M, then each CBG can be first allocated (A / M) data bits, ceiling (A / M) data bits, or floor (A / M) data bits. Next, by replacing the number of data bits allocated to each CBG with the number of bits Ck corresponding to the TBS in method X-1 / 2 / 3, multiple CBs belonging to each CBG can be configured by applying method X-1 / 2 / 3. At the same time, the coded bits for a single CBG can be mapped / sent only on a single SG or RBG.

[0254] At the same time, a scheme for changing the number of symbols configured for one SG according to the number of symbols allocated for data transmission and / or the number of RBs (or TBSs) allocated for data transmission is also feasible. For example, (in order to make the number of CBGs the same as much as possible) the number of symbols per SG can be configured to increase as the number of symbols allocated for data transmission increases. Moreover, (in order to make the CBG size the same as much as possible) the number of symbols per SG can be configured to decrease as the number of RBs (or TBSs) allocated for data transmission increases. Similarly, a scheme for changing the number of RBs configured for one RBG according to the number of RBs allocated for data transmission and / or the number of symbols (or TBSs) allocated for data transmission is also feasible. For example, (in order to make the number of CBGs the same as much as possible) the number of RBs per RBG can be configured to increase as the number of RBs allocated for data transmission increases. Moreover, (in order to make the CBG size the same as much as possible) the number of RBs per RBG can be configured to decrease as the number of RBs (or TBSs) allocated for data transmission increases.

[0255] 5) Method A-5: Configure the total number of CBGs "M" and the size of CBGs "N" per TBS

[0256] The (M, N) combination for CBG configuration can be set (differently) for each TBS. Based on the maximum value M.max among the M values ​​set per TBS, the number of DCI bits indicated by the CBG for performing data scheduling and / or the UCI payload size for the corresponding A / N feedback configuration can be determined. For example, the CBG indication information and / or the A / N payload size can be set to M.max, ceiling(M.max / K)(M.max / K) or ceiling(log2(M.max)) bits. Here, K can be a positive integer, for example, K=2.

[0257] As an additional method, first, if the set of (M, N) combinations applied per TBS is named as a TBS-CBG table, it is possible to consider a scheme in which one of multiple TBS-CBG tables is indicated to the UE through semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI) in a state where multiple TBS-CBG tables are predefined / preset. In this case, the (M, N) combination corresponding to the same TBS can be configured differently between multiple TBS-CBG tables. Therefore, the UE determines the (M, N) combination corresponding to the TBS indicated by the DL / UL scheduling DCI by referring to the indicated TBS-CBG table, and is then able to operate to perform DL / UL data transmission / reception and A / N feedback transmission based on the determined (M, N) combination.

[0258] As another method, in a state where the total TBS set is divided into multiple TBS ranges, different CBG configuration methods per TBS range can be applied. For example, for TBS range 1, in contrast to configuring the number of CBGs "M" differently by method A-1 or per TBS (or, the CBS size "N" is configured equally), for TBS range 2, the number of CBGs "M" can be configured identically by method A-2 or per TBS. In this case, considering DCI overhead and / or UCI payload, TBS range 2 can be configured with a TBS larger than the TBS belonging to TBS range 1. As another method, the same CBG configuration (e.g., CBG number / size) is applied to each TBS range, but the number of CBGs / sizes, etc. are configured differently between TBS ranges. For example, for each of TBS ranges 1 and 2, the number of CBGs "M" is configured identically by method A-2 or per TBS, but different M values ​​can be set between TBS range 1 and TBS range 2. In this case, M of TBS range 2 can be set to a value greater than M of TBS range 1. For another example, for each of TBS ranges 1 and 2, the CBG size "N" is configured identically by method A-1 or per TBS, but different N values ​​can be set between TBS range 1 and TBS range 2. In this case, N of TBS range 2 can be set to a value greater than N of TBS range 1.

[0259] 6) Method A-6: Apply interleaving between CBs belonging to the same CBG before mapping data to resources

[0260] By considering the impact of interference with a specific (time selective) pattern (e.g., URLLC puncturing operation), inter-CB interleaving can be applied between multiple CBs (coded bits) belonging to the same CBG before mapping data to resources (e.g., RE). For example, for multiple CBs (coded bits) belonging to one CBG, 1) in a state where intra-CB interleaving is first applied within each CB, inter-CB interleaving is additionally applied, or 2) (if CBG-based HARQ operation is set), in a state where intra-CB interleaving is omitted, only inter-CB interleaving can be applied. Here, the mapping of data to resources includes RE mapping based on a frequency priority manner.

[0261] In all the methods proposed above, M, N and K may be set / indicated to the same value for different TBSs, or may be set / indicated to different values ​​for different TBSs, or may be set / indicated to the same value for part (e.g., N) and different values ​​for the remaining parts (e.g., M and K) according to the TBS. In addition, when considering a scheme in which DL data scheduling / transmission is performed across multiple time slots, in the methods proposed above, a symbol group (SG) can be configured / set on a time slot basis (in this case, the symbol index is applied by being replaced by the time slot index).

[0262] (B) HARQ-ACK Feedback Method

[0263] 1) Method B-1: Configure / send a (minimum) range including all NACKs on CBG index as feedback

[0264] In a state where a CBS configuration scheme (e.g., CBG number / size) is given, considering decoding errors (i.e., NACKs) across consecutive CBG indexes due to time selective interference, the UE is able to: 1) feed back the CBG index corresponding to the first NACK (on the CBG index) and the CBG index corresponding to the last NACK to the BS, or 2) feed back the CBG index corresponding to the first NACK and the distance between the first NACK and the last NACK. Here, 1) and 2) can be signaled by using an RIV (resource indication value) indication scheme applied to UL resource allocation type 0 or a combined indexing scheme applied to UL resource allocation type 1. In this case, the CBG configuration scheme may include methods A-1 / 2 / 3 / 4.

[0265] As an additional method, the UE directly selects one of the multiple CBG configuration schemes (e.g., CBG number / size), and based on the selected CBG configuration, 1) the UE determines the (minimum) CBG range including NACK, and then feeds back the corresponding NACK CBG range and the selected CBG configuration information to the BS, or 2) the UE configures a separate A / N bit per CBG, and then feeds back the configured A / N bit (together with the selected CBG configuration information) to the BS. In this case, the CBG configuration scheme may also include method A-1 / 2 / 3 / 4.

[0266] Additionally, the above method can also be applied to CBG scheduling from the BS. Specifically, 1) the first CBG index and the last CBG index to be sent (or retransmitted), or 2) the first CBS index and the total number of CBGs to be sent (or retransmitted) "L" can be indicated by the DL data scheduling DCI. In this case, the UE can operate (receive) in a state assuming / recognizing that 1) a CBG set corresponding to an index between the index including the first CBG index and the last CBG index, or 2) a CBG set corresponding to the subsequent L consecutive indexes including the first CBG index is scheduled.

[0267] 2) Method B-2: Feedback of a CBG (of the minimum size) including all NACKs in a CBG configuration of a tree structure

[0268] In a state where multiple CBG configurations (e.g., (M, N) combinations) are given based on a tree structure as in method A-3, the UE is able to operate in a manner of selecting a specific CBG configuration, and determining a CBG index including all NACKs based on the selected CBG configuration, and then feeding back the NACK CBG index and the selected CBG configuration information to the BS. Here, preferably, while including all NACKs, the NACK CBG is selected as a CBG with a minimum size. That is, the UE is able to operate in such a manner that a specific CBG configuration is selected from multiple CBG configurations with a tree structure so that a single CBG of the minimum size can include all NACKs, a CBG index including all NACKs is determined based on the selected CBG configuration, and the determined CBG index (together with the selected CBG configuration information) is fed back to the BS.

[0269] Similarly, in a state where multiple CBG configurations (based on different SG( / RBG) sizes / numbers from each other) with an SG-based (and / or RBG-based) tree structure as in Method A-4 are given, the UE may operate in such a manner as to select a CBG configuration based on a specific SG( / RBG), determine a CBG index including all NACKs based on the selected CBG configuration, and feed back the NACK CBG index and the selected CBG configuration (or corresponding SB( / RBG) configuration) information to the BS.

[0270] Additionally, the above method can be applied to CBG scheduling from the BS. Specifically, in a state where multiple CBG configurations with a tree structure (e.g., M and / or N (combination) or SG ( / RBG) size / number) are given as in method A-3 or method A-4, a CBG index based on a specific CBG configuration can be indicated by DL data scheduling DCI. In this case, the UE can operate (receive) in a state assuming / recognizing that a CBG set belonging to a corresponding CBG index is scheduled by the corresponding DCI.

[0271] 3) Method B-3: Keeping the CBG configuration and the corresponding A / N configuration the same during one HARQ process

[0272] In order to prevent unnecessary RLC-level DL data retransmission due to A / N errors of a specific CBG, the CBG configuration (used for retransmission (CBG) scheduling (indication) in the BS) and the A / N feedback configuration corresponding to the corresponding CBG configuration can remain the same when performing one HARQ process (i.e., until the end of the process). Specifically, the CBG configuration and the corresponding A / N feedback configuration initially applied / indicated to DL data scheduling / transmission with a specific HARQ process ID can operate to be kept the same until the end of the corresponding HARQ process (e.g., until the decoding of all CBs for the TB configured with DL data is successful, or before a new DL data scheduling (NDI switching) with the same HARQ process ID begins). Here, the initially applied / indicated CBG and A / N configuration information can be indicated to the UE via semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., DCI, (initial) DL data scheduling DCI). If the initially applied / indicated CBG and A / N configuration information is indicated by semi-static signaling (eg, RRC signaling), the CBG and A / N configuration information is semi-statically fixed and can remain the same throughout all HARQ processes until there is new RRC signaling.

[0273] At the same time, the UE can configure and feedback the A / N bit per CBG, and operate to feedback the NACK for the corresponding CBG until each CBG is successfully decoded (regardless of whether there is scheduling for the corresponding CBG). In addition, the UE can operate to feedback the ACK for the corresponding CBG from the moment of successful decoding (regardless of whether there is scheduling for the corresponding CBG, and until the corresponding HARQ process is terminated).

[0274] Fig.17 The signal sending process of the present invention is exemplified. Fig.17 Assume a situation where the number of CBGs per TB is set to 3 and a TB is sent (retransmitted) for the same HARQ process (ie, assuming that the previous operation of the HARQ process corresponding to the TB is terminated).

[0275] Reference Fig.17 , the UE is able to receive CBG#0 and CBG#2 of a TB (e.g., HARQ process #a) from the BS [S1702]. Here, the TB of step S1702 may be an initial transmission or a retransmission corresponding to the HARQ process #a. Moreover, it is assumed that CBG#1 has never been successfully decoded before. In this case, according to the decoding result, the UE sends A / N information corresponding to the three CBGs to the BS [S1704], sets the A / N information about CBG#1 to NACK, and sets the A / N information about CBG#0 and CBG#2 to ACK or NACK according to the decoding result. Thereafter, the BS retransmits the TB (e.g., HARQ process #a) in units of CBGs, and the UE is able to receive CBG#1 and CBG#2 for the corresponding TB [S1706]. In this case, the UE sends A / N information corresponding to the 3 CBGs to the BS [S1708], but sets the A / N information about CBG#0 to ACK due to the previous successful decoding of CBG#0, and sets the A / N information about CBG#1 and CBG#2 to ACK or NACK according to the decoding results.

[0276] 4) Method B-4: Differently set the corresponding A / N transmission time delay according to the number of scheduled CB / CBG

[0277] According to the number of CBs or CBGs scheduled simultaneously for the same TB (size), the corresponding A / N transmission time delay (i.e., the time interval between DL data reception and the transmission of the corresponding A / N feedback) can be set differently. Specifically, the smaller the number of scheduled CBs or CBGs, the corresponding A / N delay can be set to be very small. For example, compared with the case of scheduling all TBs, i.e., all CBs, the corresponding A / N delay in the case of scheduling partial CBs or CBGs can be set to be smaller. Moreover, assuming the same CBG size, the corresponding A / N delay in the case of scheduling a smaller number of CBGs can be set to be smaller. Also, in the case where the number of scheduled CBGs is the same, the corresponding A / N delay in the case of configuring a smaller CBG size can be set to be smaller.

[0278] 5) Method B-5: Differently set the CBG configuration (CBG number / size) between DL data scheduling and A / N feedback

[0279] The CBG configuration (e.g., CBG number / size) applied to DL data scheduling / transmission and the CBG configuration applied to A / N feedback corresponding to the reception of the corresponding DL data can be set differently. Here, the CBG configuration can be indicated by the DL data scheduling DCI. Specifically, the (M, N) combinations for DL data scheduling and the (M, N) combinations for A / N feedback configuration can be set to different values respectively. For example, the (M1, N1) combination and the (M2, N2) combination can be set respectively for DL data scheduling and A / N feedback. Therefore, when comparing Case 1 where M1>M2 (and N1<N2) with Case 2 where M1<M2 (and N1>N2), in Case 1, the number of bits of the DCI increases but the number of bits of the retransmitted DL data resources and A / N feedback may decrease. In Case 2, the number of bits of the DCI decreases but the number of bits of the retransmitted DL data resources and A / N feedback may increase.

[0280] 6) Method B-6: Differently set the A / N transmission time delay for each of the multiple scheduled CBGs

[0281] For multiple simultaneously scheduled CBGs, the A / N transmission time delay for each CBG can be set differently (i.e., perform TDM on the A / N for each CBG for transmission). Specifically, the A / N delay corresponding to the CBG transmitted through a lower symbol (or time slot) index can be set to be smaller. Thus, the A / N corresponding to the CBG transmitted through a lower symbol (or time slot) index can be fed back at a relatively faster symbol (or time slot) timing.

[0282] 7) Method B-7: A / N feedback configuration corresponding to the transmission (retransmission) scheduling of the TB unit (configured with M CBGs)

[0283] It is possible to indicate to the UE by semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., (initial) DL data scheduling DCI) which method to perform A / N feedback through A / N bit configuration of TB unit or A / N bit configuration of CBG unit. In the case of A / N bit configuration of CBG unit, the A / N payload size (and the PUCCH format for corresponding A / N transmission) can be set by semi-static signaling (e.g., RRC signaling). In this case, the total number of CBGs configuring the TB can be determined according to a given (fixed) A / N payload size (e.g., M bits). For example, the number of CBGs can be determined to be equal to M, which is the number of A / N bits. Therefore, the number of CBGs configuring the TB can be set the same even for different TBSs from each other, and the number of CBs configuring one CBG can be set differently according to the TBS (e.g., set to a value proportional to the TBS). Meanwhile, if the total number of CBs for which the TB is configured is equal to or less than a given A / N payload size, all A / N feedback can be configured in a manner that A / N bits are allocated per CB without grouping the CBs. On the other hand, if the total number of CBs "N" is less than a given A / N payload size "M" (bits), A / N bits are allocated per CB, and 1) the remaining (MN) bits not allocated to A / N per CB are processed as NACK, or 2) the A / N payload size itself can be changed to N (bits) equal to the total number of CBs.

[0284] At the same time, for each TBS, the number of CBs configured for the TB and the CBS configuration based on the number of CBs can be determined according to a predetermined rule (for example, the total number of CBGs configured for the TB is "M", the number of CBs configured for a single CBG is "N"). Moreover, based on the number of CBGs set for the TB, the A / N payload size and the corresponding PUCCH format can be set. For example, the PUCCH format and candidate PUCCH resource set for CBG unit A / N transmission for each TBS (according to the total number of CBGs "M" of the TBS) can be set independently (differently). Moreover, the M value and / or the corresponding PUCCH format can be indicated to the UE through semi-static signaling (for example, RRC signaling) or dynamic signaling (for example, (DL data scheduling) DCI). For example, in a state where multiple (M value, PUCCH format (and candidate PUCCH resource set)) combinations are pre-specified, a specific combination can be indicated through DCI, or the M value and PUCCH format can be independently indicated by RRC and / or DCI, respectively. Meanwhile, if the M value is indicated, a PUCCH format (and a candidate PUCCH resource set) previously assigned to the corresponding M value can be automatically determined. Alternatively, if the PUCCH format is indicated, an M value previously assigned to the corresponding PUCCH format can be automatically determined.

[0285] As another method, the N value and / or the corresponding PUCCH format can be indicated to the UE through semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., (DL data scheduling) DCI). For example, in a state where multiple N values and multiple combinations (M, PUCCH format (and candidate PUCCH resource sets)) according to the N value are pre-specified, a specific combination can be indicated through DCI, or the N value and the PUCCH format can be independently indicated through RRC signaling and / or DCI respectively. At the same time, if the N value is indicated, the PUCCH format (and candidate PUCCH resource sets) previously specified according to the N value for the M value can be automatically determined. Or, if the PUCCH format is indicated, the total number of CBGs and the number of CBs per CBG can be automatically determined with reference to the A / N payload size (e.g., M bits) according to the PUCCH format.

[0286] 8) Method B-8: A / N feedback configuration corresponding to transmitting (retransmitting) some CBGs among the M CBGs configuring the TB

[0287] In the case of scheduling the transmission (retransmission) of L or fewer CBGs among the total M CBGs configuring the TB (where L < M), the following methods can be considered.

[0288] Option 1) The same A / N payload size (e.g., M bits) as in the case of A / N feedback corresponding to TB unit transmission (retransmission) can be applied (as in Method B-7). Therefore, in practice, A / N is only mapped to L bits (corresponding to the CBGs scheduled for retransmission), and the remaining (M - L) bits (corresponding to the unscheduled CBGs) are mapped to ACK or NACK according to the decoding success / failure of the corresponding CBGs (as in Method B-3) or are processed as NACK. Option 2) An A / N payload size (and PUCCH format) different from (e.g., smaller than) the case of A / N feedback corresponding to TB unit transmission (retransmission) can be applied. In the case of Option 2, the A / N payload size (and PUCCH format) can be changed according to the number of scheduled CBGs "L". For example, the A / N payload can be configured with only L bits.

[0289] Here, L can be semi-fixed to a single value via semi-static signaling (e.g., RRC signaling) or dynamically changed via dynamic signaling (e.g., DL data scheduling DCI). In the former case, the CBG indication signaling can be configured such that, via the scheduling DCI of the CBG unit, the CBG scheduling can be up to L CBGs among a total of M CBGs. Moreover, additionally, among the total M CBGs for configuring the TB, retransmission scheduling (from the BS) is performed only for L or fewer CBGs (L < M). In this case, if the number of scheduled target CBGs exceeds L, the BS / UE can perform scheduling (DCI transmission) / A / N feedback of the TB unit.

[0290] Meanwhile, Option 1 and Option 2 can basically be applied assuming that the CBG configuration initially applied to / indicated for TB scheduling / transmission (e.g., the total number of CBGs “M” for configuring the TB, the number of CBs “N” for configuring a single CBG) remains unified during the HARQ process.

[0291] Additionally, in the case of Option 1, the A / N payload size is set with reference to the TB unit transmission (retransmission) (e.g., M bits), but for A / N feedback configured only for the actually scheduled CBGs, the CBs belonging to the L CBGs (each of which is configured with N CBs) among all the scheduled CBGs are reconfigured to M CBGs (each of which is configured with fewer than N CBs). Referring to this, all A / N feedbacks with A / N bit allocation according to the CBG unit can be configured. In this case, the BS can also perform retransmission scheduling by assuming that the M CBGs corresponding to the A / N feedback correspond to the entire CBG set. Meanwhile, in the case where the UE corresponding to the DL data receiver or the A / N transmitter is accompanied by a CB recombination process, if a NACK-to-ACK error occurs, it may lead to a mismatch between the UE and the BS in the CBG configuration (or performance degradation due to the mismatch). Considering this problem, in addition to the A / N information per CBG of M, an indicator (e.g., 1 bit) for indicating the use of NACK feedback for the TB unit (whether it exists) or the retransmission request for all TBs (whether it exists) can also be included to configure all A / N feedbacks (payloads). Based on this, if a CBS configuration mismatch occurs, the UE can map / send the corresponding indicator to the state corresponding to “TB unit NACK” or “TB retransmission request”. After receiving the indicator, the BS can perform TB scheduling again based on the initial CBG configuration before recombination.

[0292] Meanwhile, in the case of the CBG retransmission scheduling DCI corresponding to the A / N feedback in Option 2, the corresponding signaling can be configured in the following forms: 1) Refer to the retransmission CBG indication of the total number of CBGs "M", regardless of the change in the A / N payload size; or 2) Assume the CBG indication form in the state where the set of CBGs (equal to or less than M) that the UE feeds back as NACK is all CBG configurations.

[0293] Moreover, additionally, it can be indicated to the UE through semi-static signaling (e.g., RRC signaling) or dynamic signaling (e.g., (DL data scheduling) DCI) whether to apply the always same (fixed) A / N payload size (and PUCCH format) as in Option 1 for CBG (retransmission) scheduling regardless of the number of scheduled CBGs, or to apply the A / N payload size (and PUCCH format) that varies (dynamically) according to the number of scheduled CBGs as in Option 2.

[0294] 9) Method B-9: A / N feedback of CBG units only when some of (the M CBGs of the configured TB) are NACK

[0295] The A / N feedback of CBG units (e.g., allocate a separate A / N bit for each CBG) can be configured / sent only when the number of CBGs corresponding to NACK among the total M CBGs of the configured TB is equal to or less than L (L < M). Meanwhile, if the number of CBGs that are NACK exceeds L, the A / N feedback of TB units can be configured / sent. In this case, since the A / N feedback of CBG units is configured only for NACK equal to or less than L, the retransmission CBG (index) indication of the CBG unit (retransmission) scheduling DCI can configure the corresponding signaling in the following forms: 1) The form of indication for L or fewer CBGs among the total M CBGs; or 2) The CBG indication form in the state where the set of CBGs (equal to or less than L) that the UE feeds back as NACK is assumed to be all CBG configurations. For example, when i = {1...L}, for all i values, all sets of selecting i CBGs from the total M CBGs are indexed, and the UE can feedback one of the corresponding indexes to the BS to indicate the set of CBGs corresponding to NACK.

[0296] 10) Method B-10: CBG retransmission scheduling and A / N feedback in the form of limiting the maximum number of CBGs to M

[0297] In terms of BS scheduling, the BS can operate so that all CBG configurations are configured with Mr CBGs (Mr≤M) and instruct the UE to retransmit L CBGs (L≤Mr) out of the Mr CBGs. Here, Mr (and L) may change at each (retransmission) scheduling moment, as opposed to M having a fixed value during at least one TB transmission or one HARQ process.

[0298] In this case, the UE can operate as follows in terms of A / N feedback.

[0299] Option 1) If possible, A / N feedback can be configured based on the maximum CBS number "M". For example, the total A / N payload size is configured with M bits, and the (ML) bits corresponding to the CBGs that failed to be actually scheduled can be processed as NACK or DTX.

[0300] Option 2) A / N feedback can be configured based on the total number of CBGs "Mr" under the scheduled timing. For example, the total A / N payload size is configured with Mr bits, and the (Mr-L) bits corresponding to the CBGs that failed to be actually scheduled can be processed as NACK or DTX.

[0301] Option 3) A / N feedback can be configured based on the number of scheduled CBGs "L". For example, by configuring the total A / N payload size with L bits, the A / N bits can be mapped / sent per scheduled CBG.

[0302] In the case of option 2 / 3, the A / N payload size can vary according to the Mr value or the L value, so that the PUCCH format (and candidate PUCCH resource set) used for A / N feedback transmission can be changed.

[0303] Moreover, in this case, all Mr CBG configurations used for retransmission scheduling in the BS can be configured for all CB sets that configure TBs (i.e., all CB sets are equal to all TBs) or limited to a specific part of all CBs (i.e., all CBG sets correspond to a part of TBs). In the former case, the Mr value of a specific scheduling timing for one TB transmission or one HARQ process can be limited to always be less than or equal to the Mr value of the previous scheduling timing. In the latter case, the specific part of the CB may mean: 1) a CB set belonging to the L CBGs scheduled with the previous scheduling timing; or 2) a CB set belonging to the CBGs among the L scheduled CBGs that are fed back as NACK from the UE.

[0304] 11) Method B-11: Processing of (subsequent) CBG scheduled for retransmission before A / N feedback is sent

[0305] It may happen that at a certain moment before sending the A / N feedback (hereinafter referred to as the first A / N) corresponding to the reception of a specific TB (hereinafter referred to as the original TB), a CBG retransmission (hereinafter referred to as the subsequent CBG) is scheduled for the same TB. In this case, it may happen that as the decoding end moment of the subsequent CBG becomes too late, the operation of sending the A / N feedback reflecting the reception combination of the subsequent CBG through the first A / N timing may not be performed. Here, reception combination may mean such an operation: clearing (i.e., refreshing) the received signal stored in the buffer and then storing the subsequent CBG. In this case, the UE may: 1) send the A / N feedback based on the decoding result of the original TB only at the first A / N moment, and perform reception combination (for A / N feedback at subsequent moments) on the subsequent CBG; or 2) send the A / N feedback based on the decoding result reflecting the reception combination of the subsequent CBG at a certain moment later than the first A / N moment. In the case of 2), the A / N transmission at the first A / N moment may be discarded, or only the A / N of the original TB may be sent.

[0306] At the same time, in the case of UL data scheduling, (subsequent) CBG retransmissions for the same TB can also be scheduled at a certain moment before sending a specific (or initial) TB in a manner similar to the above description. Here, the original TB sending moment (hereinafter referred to as TX timing 1) and the subsequent CBG sending moment (hereinafter referred to as TX timing 2) are different from each other, and Tx timing 2 can be indicated as a moment after TX timing 1. In this case, the UE is able to send only the signal retained after excluding the CBG corresponding to the subsequent CBG from the scheduled original TB signal through TX timing 1 (for example, the RE / RB / symbol of the punctured mapping corresponding CBG), and can also send the subsequent CBG scheduled for retransmission in its entirety through TX timing 2.

[0307] Moreover, in the case of cross-slot scheduling for DL ​​data, (subsequent) CBG retransmissions for the same TB can also be scheduled at a certain moment before a specific (or initial) TB reception in a manner similar to the above description. Here, the original TB reception moment (hereinafter referred to as TX Timing 1) and the subsequent CBG reception moment (hereinafter referred to as TX Timing 2) are different from each other, and Tx Timing 2 can be indicated as a moment after TX Timing 1. In this case, the UE is able to receive only the signal (e.g., RE / RB / symbol of the punctured mapped CBG) retained after excluding the CBG corresponding to the subsequent CBG from the scheduled original TB signal through TX Timing 1, and can also receive the subsequent CBG scheduled for retransmission in its entirety through TX Timing 2.

[0308] (C) Soft Buffer Operation Method

[0309] 1) Method C-1: Determine the minimum buffer size per CB by referring to the sum of the number of CBs belonging to the CBG corresponding to the NACK

[0310] It is possible to consider a solution in which the buffer size Bc obtained by dividing the (minimum) buffer size Bt per TB assigned to one HARQ process or one TB by the sum of the number of CBs Cn belonging to the CBGs fed back by the UE as NACK (to the BS) as the minimum buffer size per CB in terms of UE reception (e.g., Bc=Bt / Cn). Specifically, it is possible to consider replacing C with Cn in the following formula 4. Here, for example, the minimum buffer size per CB may mean the minimum number of (soft channel) bits that the UE should save to the buffer per CB for TB transmission.

[0311] [Formula 5]

[0312]

[0313] In this case, compared with the existing scheme based on A / N feedback in TB units, (for example, because C>Cn) there is an advantage of being able to increase the minimum buffer size per CB. Moreover, Cn applied to one HARQ process or one TB transmission can be determined by: 1) only referring to the initial A / N feedback (CBG with NACK) configured by CBG units (i.e., applying the same Cn until the HARQ process is terminated); or 2) referring to the A / N feedback (CBG with NACK) at each moment in the A / N transmission moment (i.e., determining Cn according to the NACK CBG at each scheduling / feedback moment).

[0314] At the same time, it is possible to consider a scheme of applying Cn of method C-2 (i.e., the sum of the number of CBs belonging to CBGs whose feedback is NACK or requires retransmission (or fails to receive ACK feedback) on the BS side) to Formula 5.

[0315] 2) Method C-2: (Limited / Circular Buffer) Rate Matching Operation in BS for Retransmitting CBG Signals

[0316] When performing (limited / circular buffer) rate matching on the BS side with reference to all CBGs that are fed back as NACK or need to be retransmitted (from the UE), a mismatch between the NACK CBG on the BS side and the NACK CBG fed back by the UE may be generated due to A / N errors. In order to eliminate such a mismatch, the following operations can be considered.

[0317] 1) The BS may operate to always perform retransmission scheduling for all CBGs that are fed back as NACK (or fail to receive ACK feedback) (from the UE) together / simultaneously (i.e., the operation of retransmission scheduling for only some NACK CBGs is not allowed) (the UE operates in a state assuming / asserting this), or

[0318] 2) (Although the BS allows the operation of performing retransmission scheduling for some of all NACK CBGs), it is possible to consider indicating to the UE through DL data scheduling DCI the operation of all CBG information (e.g., the number / index of NACK CBGs) that are fed back as NACK or need to be retransmitted (or, failed to receive ACK feedback) on the BS side.

[0319] In this case, the minimum buffer size per CB as the BS transmission side can be determined by dividing the (minimum) buffer size per TB Bt assigned to one HARQ process or one TB by the buffer size Bc obtained by the sum of the number of CBGs fed back as NACK on the BS side or the number of CBs that need to be retransmitted (or failed to receive ACK feedback) Cn (for example, Bc = Bt / Cn). In particular, it can be considered to replace C with Cn in the following formula 2.

[0320] [Formula 6]

[0321]

[0322] In this case, compared with the existing scheme that only applies TB unit retransmission, (for example, because C>Cn) there is an advantage of being able to increase the minimum buffer size per CB. Cn applied to one TB transmission can be determined by: 1) referring to the CBG unit retransmission timing initially performed (i.e., applying the same Cn until the HARQ process is terminated); or 2) determining at each CBG unit retransmission moment (i.e., Cn is determined at each moment according to the number of CBSs that are fed back as NACK or need to be retransmitted (or, ACK feedback is not received).

[0323] Meanwhile, through the data scheduling DCI, if the indication information about the CBS index to be sent (retransmitted) and the buffer refresh indication information for each CBG are notified by signaling, the signaling of the buffer refresh indication information may not be required for the CBS index for which the indication is not sent (retransmitted). Here, the buffer refresh information may include indication information indicating whether the corresponding buffer is cleared by refreshing before the received CBG signal is saved in the buffer or the received CBG signal is combined with the previously saved CBG signal without clearing the buffer. If the indication is to clear the buffer by refreshing the CBG index for which the indication is not sent (retransmitted) (or conversely, the indication is combined without clearing the buffer), the UE is able to operate in a state where the corresponding CBG index is identified / assumed to be a CBG for which ACK feedback is received or retransmission is not required on the BS side. On the contrary, if the indication is combined without clearing the buffer (or conversely, the indication is cleared by refreshing the buffer), the UE may not perform any operation on the corresponding CBG index (the receive (Rx) buffer corresponding thereto).

[0324] 3) Method C-3: Applying power offset to A / N feedback PUCCH transmission according to CBG unit scheduling

[0325] The power offset added / applied to the PUCCH transmission carrying A / N feedback configured by the CBG unit can be determined as a value proportional to the value of option 1 / 2 / 3 / 4 / 5 / 6 / 7. Therefore, as the number of CBGs increases in option 1 / 2 / 3 / 4 / 5 / 6 / 7, the corresponding power offset can be added / applied with a larger value.

[0326] Option 1) (without distinguishing A / N) Total number of CBGs that are assigned A / N bits or become the target of A / N feedback

[0327] Option 2) Number of CBGs scheduled from BS

[0328] Option 3) Number of NACK CBGs (at the BS) indicated from the BS in method C-2

[0329] Option 4) Number of NACK CBGs at the UE

[0330] Option 5) Considering the A / N feedback configuration scheme as in Method B-3, the sum of the number of CBGs in Option 2 and the number of CBGs that were fed back as ACK despite not being scheduled

[0331] Option 6) The sum of the number of CBGs in Option 3 and the number of CBGs that were fed back as ACKs despite not being scheduled

[0332] Option 7) Number of remaining CBGs except for the CBG to which the power offset transmitted by A / N PUCCH has been added / applied at a specific timing as ACK feedback at a certain timing before a specific timing

[0333] (D) Mismatch handling method

[0334] 1) Method D-1: Mismatch between the A / N information per CBG fed back by the UE and the CBG retransmission schedule from the BS

[0335] A mismatch between the A / N information per CBG fed back by the UE and the corresponding CBG index scheduled for retransmission from the BS may occur (due to A / N error). For example, some CBGs fed back as NACK by the UE may not be included in the CBG index scheduled from the BS or / and CBGs that have been fed back as ACK may be included therein. In this case, the UE may be configured to perform the following operations.

[0336] Option 1) Map the combined decoded A / N results for the CBGs previously fed back as NACK in the scheduled CBGs, or

[0337] Option 2) Re-map ACK (without combining / decoding) for the CBG previously fed back as ACK among the scheduled CBGs [see Method B-3], or

[0338] Option 3) Map NACK to all CBGs, or

[0339] Option 4) Perform NACK feedback per TB or retransmission request for the entire TB, or

[0340] Option 5) Discard the corresponding CBG scheduling DCI.

[0341] Meanwhile, if all CBGs previously fed back as NACK are included in the scheduled CBG, one of Option 1 and Option 2 is applied. Otherwise, one of Option 3 to Option 5 may also be applied.

[0342] 2) Method D-2: Mismatch between the CRC applied to the entire TB and the CRC applied per CB and / or CBG

[0343] The Rx CRC check result (e.g., pass / fail) at the UE may be different among the CRC applied to the entire TB, the CRC applied in units of CBs, and the CRC applied in units of CBGs. Here, if the CRC check result is "pass", it means that the corresponding data block is successfully / correctly detected. If the CRC check result is "fail", it means that the corresponding data block is not successfully / correctly detected.

[0344] For example, the CRC check results in units of CB and / or CBG may all be "passed" (i.e., the CRC check based on the CB CRC passes), but on the contrary, the CRC check result of the entire TB may be "failed" (i.e., the CRC check based on the TB CRC fails). On the contrary, at least one of the CRC check results in units of CB and / or CBG fails (i.e., the CRC check based on the CB CRC fails), but on the contrary, the CRC check result of the entire TB may pass (i.e., the CRC check based on the TB CRC passes). In this case, the UE can apply one of options 3 to 5 of method D-1. Options 3 to 5 of method D-1 are listed as follows.

[0345] Option 3) Map NACK for all CBGs.

[0346] Option 4) Perform NACK feedback in TB units or retransmission request for the entire TB.

[0347] Option 5) Ability to discard the corresponding CBG scheduling DCI.

[0348] For another example, all CRC check results in units of CB belonging to a specific CBG pass, but on the contrary, the CRC check result of the entire corresponding CBG may fail. On the contrary, although at least one CRC check result in units of CB belonging to a specific CBG fails, the CRC check result of the entire corresponding CBG may pass. In this case, the UE can send feedback by mapping the corresponding CBG to NACK, or apply one of options 3 to 5 of method D-1.

[0349] (E) CBG scheduling DCI configuration

[0350] 1) Method E-1: RV configuration and settings in the scheduling (DCI) of the CBG unit

[0351] Regarding the RV field in the (retransmission) scheduling DCI in CBG units, 1) only one RV field of the same size as the RV field of the scheduling DCI in TB units is configured, and the indicated RV value is uniformly applied to the entire CBG of the scheduling (here, the number of branches of the RV value can be configured to be equal to the case of scheduling in TB units), or 2) a separate RV field is configured for each CBG, but can be configured to have a size smaller than the size of the RV field of the scheduling DCI in TB units (however, the number of branches of the RV value can be configured to be smaller than the case of scheduling in TB units).

[0352] 2) Method E-2: Perform retransmission scheduling on some CBGs (among the M CBGs configured with TB)

[0353] It can operate to achieve retransmission scheduling for at most L CBGs out of a total of M CBGs of a configured TB (L < M). Here, a single value of L can be indicated to the UE via semi-static signaling (e.g., RRC signaling). Thus, up to L CBGs out of a total of M CBGs can be indicated by CBG-unit scheduling DCI from the BS, and the scheduling DCI in terms of TB (or a flag indicating the transmission (retransmission) scheduling in terms of TB in the indication DCI) can be applied to the CBG retransmission scheduling for more than L CBGs. Specifically, when i = {1...L}, a scheme can be considered where all combinations of selecting i CBGs from a total of M CBGs are considered, and a set / combination of CBGs corresponding to one of the corresponding indices is indicated to the UE via the CBG retransmission scheduling DCI.

[0354] 3) Method E-3: Use the NDI field in the scheduling (DCI) in terms of CBG unit

[0355] The NDI field can be interpreted differently depending on whether it is for the transmission (retransmission) of the entire TB or for the retransmission of some CBGs (among all CBGs of the configured TB). For example, once it is indicated via DCI that all CBGs of the configured TB are transmitted, the combination in which the NDI bit is toggled is recognized as the scheduling for new data transmission. Thus, the case where some of all CBGs are indicated to be transmitted via DCI can be recognized as retransmission (rather than new data), and the NDI field can be used for another specific purpose. Another example is that an indicator indicating whether it is the transmission of the entire TB or the transmission of some CBGs can be directly signaled via DCI. In this case, once the transmission of the entire TB is indicated, the combination in which the NDI bit is toggled can be recognized as the scheduling for new data transmission. Thus, the latter case (i.e., the indication of some CBG transmission) can be recognized as retransmission, and the NDI field can be used for another specific purpose. Meanwhile, if the NDI field is used for another specific purpose, the NDI field can indicate: 1) whether to save the received CBG signal to the Rx buffer corresponding to the corresponding CBG index by combining it with the previously saved signal or to empty the buffer by only refreshing the previously saved signal and then re-save the received CBG signal (i.e., CBG buffer flush indicator, CBGFI), or 2) the CBG (index) of the transmission (retransmission) (i.e., CBG transmission indicator, CBGTI).

[0356] 4) Method E-4: Use the buffer flush indicator field in the scheduling (DCI) in terms of CBG unit

[0357] The buffer refresh indicator field can be interpreted differently in the case of data retransmission (without NDI switching) or in the case of new data transmission (with NDI switching). For example, in the case of data retransmission, it can be used according to the original usage of the buffer refresh indicator to indicate whether the buffer is refreshed and cleared before the received CBG signal (CBG by CBG) is saved in the buffer or the received CBG signal is combined without clearing the buffer. At the same time, in the case of new data transmission, since the buffer refresh operation before the storage of the receiving signal is basically taken as a prerequisite, the buffer refresh indicator can be used for another specific purpose. In the case where the buffer refresh indicator field is used for another specific purpose, the buffer refresh indicator field may include bits indicating TBS and / or MCS information of the scheduled data. In contrast, the TBS / MCS field in the DCI for scheduling new data transmission includes TBS / MCS information, but in contrast, a bit for configuring the buffer refresh indicator may be included in the DCI for scheduling data retransmission.

[0358] 5) Method E-5: Use CBGTI (and CBGFI) fields in the scheduling (DCI) of the CBG unit

[0359] Based on the value indicated by the CBGTI field in the DCI (or a combination of this value and another value indicated by the CBGFI field), a buffer refresh for a specific CBG (set) can be indicated. First, each bit of the configuration CBGTI field can be used to individually indicate whether there is a transmission (retransmission) for each CBG index. For example, bit "1" indicates the transmission (retransmission) of the CBG (corresponding to the corresponding bit), and bit "0" indicates that the corresponding CBG is not sent (retransmitted). In addition, the CBGFI field / bit can be used to indicate whether to perform a buffer refresh on the CBG that is indicated to be sent (retransmitted) through the CBGTI field. For example, bit "1" can indicate a refresh buffer (for the CBG that is indicated to be sent (retransmitted)), and bit "0" can indicate that the corresponding buffer is not refreshed.

[0360] First, in a state where only the CBGTI field in the DCI is configured / set (without a separate CBGFI field configuration) [hereinafter referred to as CBG mode 1], all bits of the corresponding CBGTI field (without NDI switching) can be indicated as "0". In this case, it is specified / recognized (by the UE) that the transmission (retransmission) of all CBGs configuring a given TB is indicated while the buffer refresh operation for all CBGs is indicated. Therefore, the UE can operate to save the newly received CBG signal to the buffer after refreshing the signal previously saved to the buffer. At the same time, in CBG mode 1, all bits of the CBGTI field can be indicated as "1" (in a state where NDI is not switched). In this case, in a state where the buffer refresh operation is not indicated, it is specified / recognized (by the UE) that the transmission (retransmission) of all CBGs configuring a given TB is indicated.

[0361] Secondly, in a state where both the CBGTI field and the CBGFI field in the DCI are configured / set [hereinafter referred to as CBG mode 2], all bits of the configured CBGTI field (without NDI switching) can be indicated as "0". In this case, it is specified / recognized (by the UE) that the transmission (retransmission) of all CBGs for configuring a given TB is indicated. In this state, additionally, if the CBGFI bit is indicated as "0", it can be specified / recognized (by the UE) that the buffer refresh operation for some specific CBGs (hereinafter referred to as CBG subgroup 1) is indicated [case 1]. If the CBGFI bit is indicated as "1", it can be specified / recognized that the buffer refresh operation for some other specific CBGs (hereinafter referred to as CBG subgroup 2) is indicated [case 2]. The CBGs belonging to CBG subgroup 1 and CBG subgroup 2 can be configured completely exclusive of each other or partially identical to each other (and the union of the corresponding CBGs is the entire CBG set). At the same time, in CBG mode 2, (when NDI is not switched) if all bits of the configuration CBGTI field are indicated as "1" and the CBGFI bit is indicated as "1" (or "0"), it is stipulated / recognized (by the UE) that the buffer refresh operation for all CBGs is indicated while (or not indicated) the transmission (retransmission) of all CBGs configuring a given TB is indicated.

[0362] Meanwhile, considering the early termination of the TB decoding operation in the UE, 1) decoding is performed one by one in a CBG-by-CBG alternating manner for multiple CBGs (for example, decoding is performed in the order of CB1 in CBG-1=>CB1 in CBG-2=>...CB1 in CBG-M=>CB2 in CBG-1=>...), or 2) decoding is performed sequentially per CBG (index) by CBG unit (for example, decoding is performed in the order of CB in CBG-1=>CB in CBG-2=>...). If a NACK CBG is generated, NACK can be fed back for all CBGs (indexes) thereafter (by skipping the decoding operation).

[0363] At the same time, for DL / UL data sent based on the SPS scheme, retransmission scheduling in CBG units and A / N feedback configuration operations per CGB may not be applied / configured. Therefore, only for DL / UL data sent based on general scheduling rather than the SPS scheme, retransmission scheduling in CBG units and A / N feedback configuration operations per CBG can be applied / configured. In addition, for DL / UL data sent based on SPS, scheduling in TB units and A / N feedback per TB (i.e., TB level) (for example, configuring / sending 1 bit of A / N for one TB) operations can be applied / configured. Moreover, for DL / UL data (and / or Msg 3 scheduled from RAR accompanying the random access procedure and Msg 4 sent for contention resolution purposes) scheduled by sending DCI based on UE (group) CSS (or a specific DCI format, for example, a TM common DCI format in the form of DCI format 0 / 1A in LTE (for example, commonly set / used for different TMs)), retransmission scheduling in units of CBG and A / N feedback configuration operations on a per-CBG basis may not be applied / configured. Therefore, retransmission scheduling in units of CBG and A / N feedback configuration operations on a per-CBG basis may be applied / configured only for DL / UL data sending scheduled by sending DCI based on USS rather than CSS (or a TM-specific DCI format set / used only for a specific TM). On the other hand, for DL / UL data (and / or Msg3 / 4) scheduled to be sent via CSS-based DCI (or TM common DCI format), scheduling in TB units and A / N feedback operations per TB (TB level) can be applied / configured (i.e., A / N feedback at the TB level is configured).

[0364] Meanwhile, in the case of configuring retransmission scheduling in CBG units and A / N feedback configuration operation per CBG, if A / N feedback at the TB level is configured according to the above reasons (or other reasons, such as UE bundling A / N per CBG in order to reduce the A / N payload, or A / N bundling operation is indicated by the BS), the A / N scheme can vary depending on whether A / N only for a single TB is sent without multiplexing [case 1] or multiple A / Ns for multiple TBs are sent by multiplexing [case 2]. For example, in case 1, after configuring a 1-bit A / N payload, AN can be sent by using a PUCCH format / resource that supports a small payload (e.g., a maximum of 2 bits). On the other hand, in case 2, if the number of CBGs per TB is set to N, option 1) A / N for TBs is mapped identically and repeatedly to N bits, or option 2) A / N for TBs can be mapped to 1 bit corresponding to a specific (e.g., lowest) CBG index. Meanwhile, in the case of configuring retransmission scheduling in CBG units and A / N feedback configuration operations on a CBG-by-CBG basis, Option 1) and Option 2) may be applied regardless of Case 2.

[0365] In case 2, by configuring a multi-bit A / N payload including N bits of A / N corresponding to the corresponding TBs, the UE can send A / N using a PUCCH format / resource that supports a large payload (e.g., more than 3 bits). The multi-bit A / N payload may include A / N information corresponding to multiple TBs. For example, the multi-bit A / N payload may include multiple N-bit A / Ns corresponding to multiple TBs.

[0366] At the same time, considering the case where the intentional URLLC perforation operation as described above is applied in a co-channel inter-cell environment, it may be preferred to minimize the interference effect caused by the URLLC signal sent in a specific cell on the DMRS signal for DL / UL data reception in another cell. To this end, it is possible to consider the operation of delivering / exchanging symbol position information for DMRS transmission in each cell and / or symbol position information for URLLC (perforation) transmission in each cell between cells.

[0367] The method proposed in the present invention may not be limited to DL data scheduling and transmission situations, and may also be applied in the same / similar manner to UL data scheduling and transmission situations (for example, according to the CB / CBG configuration of the TB, UL data transmission timing setting, CBG scheduling DCI configuration, etc.). In this regard, in the method proposed in the present invention, DL data (scheduling DCI) can be replaced by UL data (scheduling DCI).

[0368] Fig.18 The diagram shows a BS and a UE applicable to the present invention.

[0369] refer to Fig.18 , the wireless communication system includes a BS 110 and a UE 120. When the wireless communication system includes a relay, the BS or the UE can be replaced by the relay.

[0370] BS 110 includes a processor 112, a memory 114, and a radio frequency (RF) unit 116. Processor 112 may be configured to implement the process and / or method proposed by the present invention. Memory 114 is connected to processor 112 and stores various information related to the operation of processor 112. RF unit 116 is connected to processor 112 and sends and / or receives RF signals. UE 120 includes a processor 122, a memory 124, and an RF unit 126. Processor 122 may be configured to implement the process and / or method proposed by the present invention. Memory 124 is connected to processor 122 and stores information related to the operation of processor 122. RF unit 126 is connected to processor 122 and sends and / or receives RF signals.

[0371] The aforementioned embodiments are realized by the combination of the structural elements and features of the present invention in a predetermined manner. Unless otherwise mentioned, each structural element or feature can be considered to be selective. Each structural element or feature can be put into practice without being combined with other structural elements or features. In addition, embodiments of the present invention can be constructed by combining some structural elements and / or features. The order of operations described in the embodiments of the present invention can be changed. Some structural elements or features of an embodiment can be included in another embodiment, and can be replaced with the corresponding structural elements or features of another embodiment. Moreover, it is obvious that claims without obvious reference relationships in a specific claim can be combined to constitute an embodiment or new claims can be added by amendments after the application is submitted.

[0372] The embodiments of the present invention have been described based on the data transmission and reception between the BS (or eNB) and the UE. Such a transmission and reception relationship can also be extended to the transmission and reception of signals between the UE and the relay or the BS and the relay in the same / similar manner. The specific operations that have been described as being performed by the BS can be performed by the upper nodes of the BS as appropriate. In other words, it is obvious that various operations performed in a network including a BS and a plurality of network nodes for communicating with the UE can be performed by the BS or network nodes other than the BS. The BS can be replaced with terms such as a fixed station, a node B, an eNode B (eNB), and an access point. In addition, the term UE can be replaced with terms such as UE (MS) and a mobile subscriber station (MSS).

[0373] According to the embodiments of the present invention, various means such as hardware, firmware, software or a combination thereof may be implemented. If implemented by hardware according to the embodiments of the present invention, the embodiments of the present invention may be implemented by one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, etc.

[0374] If implemented by firmware or software according to an embodiment of the present invention, the embodiment of the present invention may be implemented by a module, process or function that performs the functions or operations described above. The software code may be stored in a storage unit and then driven by a processor. The storage unit may be arranged inside or outside the processor to send data to the processor and receive data from the processor via various well-known devices.

[0375] It will be apparent to those skilled in the art that the present invention may be implemented in other specific forms without departing from the spirit and essential features of the present invention. Therefore, the above embodiments are considered to be illustrative rather than restrictive in all respects. The scope of the present invention should be determined by the reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

[0376] Industrial Applicability

[0377] The present invention can be applied to UE, BS or other equipment in a wireless mobile communication system.

Claims

1. A method for sending hybrid automatic repeat request-acknowledgement HARQ-ACK information based on a code block group CBG by a wireless communication device, the method comprising: Receiving information about the number of CBGs "M" through radio resource control RRC signaling; Performing data reception on a transport block TB including a plurality of code blocks CB, the data reception being related to a specific HARQ process; In response to the data reception, sending a first HARQ-ACK response including corresponding HARQ-ACK information for each CBG according to the TB; performing data re-reception for the TB, the TB being re-transmitted to the wireless communication device in association with the same specific HARQ process; and In response to the data re-reception, sending a second HARQ-ACK response including corresponding HARQ-ACK information for each CBG according to the TB, Wherein, based on the information of the number of CBGs configured in the wireless communication device being "M", each of the first HARQ-ACK response and the second HARQ-ACK response includes a total of "M" bits of HARQ-ACK information, and Wherein, based on the total number of the multiple CBs in the TB being "K" and "M">"K", i) each of the K CBGs of the TB includes 1 CB, and ii) the "MK" bits of the total "M" bits of HARQ-ACK information that are not associated with the K CBGs are configured as negative ACK, NACK.

2. A device for processing a signal for wireless communication, the device comprising: at least one memory configured to store one or more instructions; and at least one processor configured to execute the one or more instructions, wherein, when executing the one or more instructions, the at least one processor obtains information about the number of CBGs "M" through radio resource control RRC signaling, performs data reception for a transport block TB including a plurality of code blocks CB, the data reception being related to a specific HARQ process, performs transmission of a first HARQ-ACK response including corresponding HARQ-ACK information for each CBG of the TB in response to the data reception, performs data re-reception for the TB, the TB being re-sent to the device in association with the same specific HARQ process, and transmits a second HARQ-ACK response including corresponding HARQ-ACK information for each CBG of the TB in response to the data re-reception, Wherein, based on the information of the number of CBGs configured in the device being "M", each of the first HARQ-ACK response and the second HARQ-ACK response includes a total of "M" bits of HARQ-ACK information, and Wherein, based on the total number of the multiple CBs in the TB being "K" and "M">"K", i) each of the K CBGs of the TB includes 1 CB, and ii) the "MK" bits of the total "M" bits of HARQ-ACK information that are not associated with the K CBGs are configured as negative ACK, NACK.

3. The apparatus according to claim 2, further comprising: Transceiver, The device is a user equipment in a wireless communication system.

4. The device according to claim 2, wherein: The apparatus is a processing device configured to control user equipment to operate in a wireless communication system.

5. A method for receiving hybrid automatic repeat request-acknowledgement HARQ-ACK information based on a code block group CBG by a wireless communication device, the method comprising: Sending information about the number of CBGs "M" to the user equipment UE through radio resource control RRC signaling; performing data transmission on a transport block TB including a plurality of code blocks CB, the data transmission being associated with a specific HARQ process; receiving, from the UE in response to the data transmission, a first HARQ-ACK response including corresponding HARQ-ACK information for each CBG according to the TB; performing data retransmission for the TB, the TB being retransmitted to the wireless communication device in association with the same specific HARQ process; as well as In response to the data retransmission, receiving a second HARQ-ACK response including corresponding HARQ-ACK information for each CBG according to the TB, wherein the information based on the number of CBGs configured in the UE is "M", and each of the first HARQ-ACK response and the second HARQ-ACK response includes a total of "M" bits of HARQ-ACK information, and Wherein, based on the total number of the multiple CBs in the TB being "K" and "M">"K", i) each of the K CBGs of the TB includes 1 CB, and ii) the "MK" bits of the total "M" bits of HARQ-ACK information that are not associated with the K CBGs are configured as negative ACK, NACK.

6. A wireless communication device, comprising: Transceiver; and at least one processor configured to, via radio resource control RRC signaling, send information about the number of CBGs "M" to a user equipment UE, perform data transmission for a transport block TB including a plurality of code blocks CB via the transceiver, the data transmission being related to a specific HARQ process, receive, via the transceiver, from the UE a first HARQ-ACK response including corresponding HARQ-ACK information for each CBG of the TB in response to the data transmission, perform data retransmission for the TB, the TB being retransmitted to the wireless communication device in association with the same specific HARQ process, and receive, in response to the data retransmission, a second HARQ-ACK response including corresponding HARQ-ACK information for each CBG of the TB, Wherein, based on the information of the number of CBGs configured in the UE being "M", each of the first HARQ-ACK response and the second HARQ-ACK response includes a total of "M" bits of HARQ-ACK information, and Wherein, based on the total number of the multiple CBs in the TB being "K" and "M">"K", i) each of the K CBGs of the TB includes 1 CB, and ii) the "MK" bits of the total "M" bits of HARQ-ACK information that are not associated with the K CBGs are configured as negative ACK, NACK.

7. The device according to claim 6, wherein: The device is a base station in a wireless communication system.

Images