KR20220099026A - A method and apparatus for scheduling multiple data channels in a communication system - Google Patents

Abstract

The present invention relates to a method and a device for scheduling a plurality of data channels in a communication system, in which a terminal and a base station can smoothly communicate with each other. The method of the present invention comprises the steps of: receiving higher layer signaling from a base station; receiving downlink control information (DCI) from the base station; receiving data from the base station; and determining a hybrid automatic repeat request (HARQ) codebook.

Description

A method and apparatus for scheduling multiple data channels in a communication system {A method and apparatus for scheduling multiple data channels in a communication system}

The present disclosure relates to a mobile communication system, and more particularly, to a method of scheduling a plurality of data channels. .

Efforts are being made to develop an improved 5G communication system or pre-5G communication system in order to meet the increasing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G Network) communication system or a long term evolution (LTE) system after (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in a very high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to alleviate the path loss of radio waves and increase the propagation distance of radio waves in the very high frequency band, in the 5G communication system, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, for network improvement of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud radio access network: cloud RAN), an ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Technology development is underway. In addition, in the 5G system, the advanced coding modulation (ACM) methods FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), and advanced access technologies FBMC (Filter Bank Multi Carrier), NOMA (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

On the other hand, the Internet is evolving from a human-centered connection network where humans create and consume information to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers, etc. with IoT technology, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required. , M2M), and MTC (Machine Type Communication) are being studied. In the IoT environment, an intelligent IT (Internet Technology) service that collects and analyzes data generated from connected objects and creates new values in human life can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, in technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication), 5G communication technology is implemented by techniques such as beam forming, MIMO, and array antenna. there will be The application of a cloud radio access network (cloud RAN) as the big data processing technology described above is an example of the convergence of 5G technology and IoT technology.

The present disclosure provides a method and apparatus in which one physical downlink control channel (PDCCH) schedules a physical downlink shared channel (PDSCH) for a plurality of cells in a communication system.

In addition, the present disclosure provides a method of determining a downlink assignment index (DAI) when scheduling a PDSCH for a plurality of cells using one PDCCH in a communication system.

Accordingly, according to various embodiments of the present disclosure, in a method performed by a terminal in a communication system, the method comprising: receiving configuration information including information on a control region of a serving cell from a base station through higher layer signaling; receiving downlink control information (DCI) including a downlink assignment index (DAI) field from the base station through a physical downlink control channel (PDCCH) based on the information on the control region; receiving data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and determining a hybrid automatic repeat request (HARQ) codebook based on the data reception result and the DAI field, wherein the HARQ codebook is included in the DAI field, the PDCCH monitoring time corresponding to the PDCCH and the serving It is characterized in that it is determined based on a counter DAI value determined based on the number of PDSCHs scheduled up to the cell and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a method performed by a base station in a communication system, the method includes: transmitting configuration information including information on a control region of a serving cell to a terminal through higher layer signaling; transmitting downlink control information (DCI) including a downlink assignment index (DAI) field to the terminal through a physical downlink control channel (PDCCH) based on the information on the control region; transmitting data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and receiving, from the terminal, a hybrid automatic repeat request (HARQ) codebook determined based on the data reception result and the DAI field, wherein the HARQ codebook is included in the DAI field. PDCCH monitoring corresponding to the PDCCH It is characterized in that it is determined based on a counter DAI value determined based on a time point and the number of PDSCHs scheduled up to the serving cell and a total DAI value determined based on the number of PDSCHs scheduled up to the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a terminal in a communication system, a transceiver; And it is connected to the transceiver and receives configuration information including information on the control region of the serving cell from the base station through higher layer signaling, and based on the information on the control region, DAI through a physical downlink control channel (PDCCH) Receives downlink control information (DCI) including a (downlink assignment index) field from the base station, and receives data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI, and the data reception result and a control unit for determining a hybrid automatic repeat request (HARQ) codebook based on the DAI field, wherein the HARQ codebook includes a PDCCH monitoring time corresponding to the PDCCH included in the DAI field and a PDSCH scheduled up to the serving cell It is characterized in that it is determined based on a counter DAI value determined based on the number of , and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a base station in a communication system, a transceiver; and connected to the transceiver, transmits configuration information including information on the control region of the serving cell to the terminal through higher layer signaling, and based on the information on the control region, DAI through a physical downlink control channel (PDCCH) Transmits downlink control information (DCI) including a (downlink assignment index) field to the terminal, and transmits data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI, and the data reception result and a controller for receiving, from the terminal, a hybrid automatic repeat request (HARQ) codebook determined based on the DAI field, wherein the HARQ codebook is included in the DAI field, the PDCCH monitoring time corresponding to the PDCCH and the serving cell It is characterized in that it is determined based on a counter DAI value determined based on the number of PDSCHs scheduled until , and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

According to the present disclosure, when PDSCHs for a plurality of cells are scheduled through one PDCCH in a communication system, by providing a method of determining scheduling information transmitted through the PDCCH, more efficient data transmission/reception can be performed.

In addition, according to the present disclosure, by providing a method for determining a DAI when scheduling a PDSCH for a plurality of cells using one PDCCH, an appropriate hybrid automatic request (HARQ) codebook (or HARQ-ACK codebook) can be called ) can be determined, and through this, the terminal and the base station can communicate smoothly.

1 is a diagram illustrating a structure of a next-generation mobile communication system according to an embodiment of the present disclosure.
2 is a diagram illustrating a radio protocol structure of a next-generation mobile communication system according to an embodiment of the present disclosure.
3 is a diagram for describing carrier aggregation (CA) according to an embodiment of the present disclosure.
4 is a diagram illustrating an example of a cross-carrier scheduling method according to an embodiment of the present disclosure.
5 is a diagram illustrating an example of setting a control resource set (CORESET) of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.
6 is a diagram illustrating a method of determining a DAI when scheduling a PDSCH for one cell through one PDCCH according to the present disclosure.
7 is a diagram illustrating a problem in the case of scheduling PDSCHs for a plurality of cells through one PDCCH according to the present disclosure.
8 is a diagram illustrating a method of determining a DAI value according to an embodiment of the present disclosure.
9 is a diagram illustrating an operation of a terminal according to an embodiment of the present disclosure.
10 is a diagram illustrating an operation of a base station according to an embodiment of the present disclosure.
11 is a diagram illustrating a structure of a terminal according to an embodiment of the present disclosure.
12 is a diagram illustrating a structure of a base station according to an embodiment of the present disclosure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention by omitting unnecessary description.

For the same reason, some components are exaggerated, omitted, or schematically illustrated in the accompanying drawings. In addition, the size of each component does not fully reflect the actual size. In each figure, the same or corresponding elements are assigned the same reference numerals.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the embodiments of the present disclosure make the present disclosure complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present disclosure is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. It may also be possible for the instructions stored in the flowchart block(s) to produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It may also be possible for instructions to perform the processing equipment to provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is also possible for the functions recited in the blocks to occur out of order. For example, two blocks shown one after another may in fact be performed substantially simultaneously, or it may be possible that the blocks are sometimes performed in a reverse order according to a corresponding function.

At this time, the term '~ unit' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and '~ unit' performs certain roles do. However, '-part' is not limited to software or hardware. '~unit' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Accordingly, according to some embodiments, '~ part' refers to components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and programs. Includes procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, components and '~ units' may be implemented to play one or more CPUs in a device or secure multimedia card. Also, according to some embodiments, '~ unit' may include one or more processors.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of functions in the present invention, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification. Hereinafter, the base station is a subject performing resource allocation of the terminal, and may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a radio access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. Of course, it is not limited to the above example. Hereinafter, the present disclosure describes a technique for a terminal to receive broadcast information from a base station in a wireless communication system. The present disclosure relates to a communication technique that converges a 5 ^th generation (5G) communication system for supporting a higher data rate after the 4 ^th generation (4G) system with Internet of Things (IoT) technology, and a system thereof. The present disclosure provides intelligent services (eg, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety related services, etc.) based on 5G communication technology and IoT-related technology. ) can be applied to

A term referring to broadcast information, a term referring to control information, a term related to communication coverage, a term referring to a state change (eg, an event), and network entities used in the following description Terms referring to, terms referring to messages, terms referring to components of an apparatus, and the like are exemplified for convenience of description. Accordingly, the present invention is not limited to the terms described below, and other terms having equivalent technical meanings may be used.

For convenience of description below, some terms and names defined in the 3rd generation partnership project long term evolution (3GPP LTE) standard may be used. However, the present invention is not limited by the above terms and names, and may be equally applied to systems conforming to other standards.

1 is a diagram illustrating a structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

1, the radio access network of the next-generation mobile communication system (hereinafter NR or 5g) is a next-generation base station (new radio node B, hereinafter, NR gNB or NR base station) 110 and a next-generation radio core network (new radio core network, NR CN) 105 . A new radio user equipment (NR UE or terminal) 115 may access an external network through the NR gNB 110 and the NR CN 105 .

In FIG. 1 , the NR gNB 110 may correspond to an evolved node B (eNB) of the existing LTE system. The NR gNB is connected to the NR UE 115 through a radio channel, and can provide a more improved service than the existing Node B. In the next-generation mobile communication system, all user traffic may be serviced through a shared channel. Accordingly, an apparatus for scheduling by collecting status information such as buffer status, available transmission power status, and channel status of UEs is required, and the NR gNB 110 may be responsible for this. One NR gNB can control multiple cells. In a next-generation mobile communication system, a bandwidth greater than or equal to the current maximum bandwidth may be applied to implement ultra-high-speed data transmission compared to current LTE. In addition, beamforming technology may be additionally grafted by using orthogonal frequency division multiplexing (OFDM) as a radio access technology. In addition, an adaptive modulation & doding (AMC) scheme for determining a modulation scheme and a channel coding rate according to the channel state of the terminal may be applied.

The NR CN 105 may perform functions such as mobility support, bearer establishment, and QoS establishment. The NR CN is a device in charge of various control functions as well as a mobility management function for the terminal, and can be connected to a plurality of base stations. In addition, the next-generation mobile communication system may be interlocked with the existing LTE system, and the NR CN may be connected to the MME 125 through a network interface. The MME may be connected to the existing base station, the eNB 130 .

2 is a diagram illustrating a radio protocol structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

2, the radio protocol of the next-generation mobile communication system is NR service data adaptation protocol (SDAP) (201, 245), NR PDCP (205, 240), NR RLC ( 210, 235), NR MAC (215, 230), and NR PHY (220, 225).

The main functions of the NR SDAPs 201 and 245 may include some of the following functions.

- Transfer of user plane data

- Mapping between a QoS flow and a DRB for both DL and UL for uplink and downlink

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

- A function of mapping a reflective QoS flow to a data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

For the SDAP layer device, the UE uses the header of the SDAP layer device for each PDCP layer device or for each bearer or for each logical channel as a radio resource control (RRC) message or whether to use the function of the SDAP layer device can be set. When the SDAP header is set, the terminal reflects the non-access stratum (NAS) quality of service (QoS) reflection setting 1-bit indicator (NAS reflective QoS) of the SDAP header and the access layer (access stratum, AS) QoS reflection As a set 1-bit indicator (AS reflective QoS), it can be instructed so that the UE can update or reconfigure mapping information for uplink and downlink QoS flows and data bearers. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used as data processing priority, scheduling information, etc. to support a smooth service.

The main functions of the NR PDCPs 205 and 240 may include some of the following functions.

- Header compression and decompression (ROHC only)

- Transfer of user data

- In-sequence delivery of upper layer PDUs

- Out-of-sequence delivery of upper layer PDUs

- Order reordering function (PDCP PDU reordering for reception)

- Duplicate detection of lower layer SDUs

- Retransmission of PDCP SDUs

- Encryption and decryption function (Ciphering and deciphering)

- Timer-based SDU discard in uplink.

In the above description, the reordering function of the NR PDCP device may refer to a function of reordering PDCP PDUs received from a lower layer in order based on a PDCP sequence number (SN). The reordering function of the NR PDCP device may include a function of delivering data to a higher layer in the rearranged order, and may include a function of directly delivering data without considering the order, It may include a function of recording PDCP PDUs, a function of reporting a status on the lost PDCP PDUs to the transmitting side, and a function of requesting retransmission of the lost PDCP PDUs. .

The main functions of the NR RLCs 210 and 235 may include some of the following functions.

- Data transfer function (Transfer of upper layer PDUs)

- In-sequence delivery of upper layer PDUs

- Out-of-sequence delivery of upper layer PDUs

- ARQ function (Error Correction through ARQ)

- Concatenation, segmentation and reassembly of RLC SDUs

- Re-segmentation of RLC data PDUs

- Reordering of RLC data PDUs

- Duplicate detection

- Protocol error detection

- RLC SDU discard function (RLC SDU discard)

- RLC re-establishment function (RLC re-establishment)

In the above description, in-sequence delivery of the NR RLC device may refer to a function of sequentially delivering RLC SDUs received from a lower layer to a higher layer. When one RLC SDU is originally divided into several RLC SDUs and received, the in-sequence delivery function of the NR RLC device may include a function of reassembling it and delivering it.

In-sequence delivery of the NR RLC device may include a function of rearranging the received RLC PDUs based on an RLC sequence number (SN) or a PDCP sequence number (SN), and may be lost by rearranging the order It may include a function of recording the lost RLC PDUs, a function of reporting a status on the lost RLC PDUs to the transmitting side, and a function of requesting retransmission of the lost RLC PDUs. have.

The in-sequence delivery function of the NR RLC (210, 235) device may include a function of sequentially delivering only RLC SDUs before the lost RLC SDU to a higher layer when there is a lost RLC SDU. can In addition, the in-sequence delivery function of the NR RLC device includes a function of sequentially delivering all RLC SDUs received before the timer starts to a higher layer if a predetermined timer expires even if there are lost RLC SDUs. can do. In addition, the in-sequence delivery function of the NR RLC device may include a function of sequentially delivering all RLC SDUs received so far to a higher layer if a predetermined timer expires even if there are lost RLC SDUs. .

The NR RLC (210, 235) device may process the RLC PDUs in the order in which they are received, regardless of the sequence number (Out of sequence delivery), and deliver it to the NR PDCP (205, 240) device.

When the NR RLC (210, 235) device receives a segment, it receives the segments stored in the buffer or to be received later, reconstructs it into one complete RLC PDU, and then delivers it to the NR PDCP device. have.

The NR RLC layer may not include a concatenation function, and may perform a function in the NR MAC layer or may be replaced with a multiplexing function of the NR MAC layer.

In the above description, the out-of-sequence delivery function of the NR RLC device may refer to a function of directly delivering RLC SDUs received from a lower layer to a higher layer regardless of order. The out-of-sequence delivery function of the NR RLC device may include a function of reassembling and delivering when one RLC SDU is originally divided into several RLC SDUs and received. The out of sequence delivery function of the NR RLC device may include a function of storing the RLC SN or PDCP SN of the received RLC PDUs and arranging the order to record the lost RLC PDUs.

The NR MACs 215 and 230 may be connected to several NR RLC layer devices configured in one terminal, and the main function of the NR MAC may include some of the following functions.

- Mapping function (Mapping between logical channels and transport channels)

- Multiplexing/demultiplexing of MAC SDUs

- Scheduling information reporting function

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

- Priority handling between logical channels of one UE

- Priority handling between UEs by means of dynamic scheduling

- MBMS service identification

- Transport format selection

- Padding function

The NR PHY layers 220 and 225 channel-code and modulate the upper layer data, make an OFDM symbol and transmit it to the radio channel, or demodulate the OFDM symbol received through the radio channel, decode the channel, and deliver the operation to the upper layer. can be done

3 is a diagram for explaining carrier aggregation (CA) according to an embodiment of the present disclosure.

Referring to FIG. 3 , when CA is configured ( 300 ), a primary cell (PCell) and a secondary cell (SCell) may be configured in the terminal.

PCell is included in PCC (primary component carrier), RRC connection establishment/re-establishment, measurement, mobility procedure, random access procedure and selection, system information acquisition, initial random access, security key change and non-access stratum (NAS) function etc. can be provided.

Since the UE performs system information monitoring through the PCell, the PCell is not deactivated, and the PCC in the UL is carried through a physical uplink control channel (PUCCH) for transmitting control information. In addition, only one RRC connection is possible between the UE and the PCell, and PDCCH/PDSCH/PUSCH (physical uplink shared channel)/PUCCH transmission is possible. Also, in the secondary cell group, a spcell of a secondary cell group (PSCell) may be configured and operated as the PCell. The operation for the PCell described below may also be performed by the PSCell.

A maximum of 31 SCells can be added, and when additional radio resource provision is required, the SCell can be configured through an RRC message message (eg, dedicated signaling). The RRC message may include a physical cell ID for each cell, and may include a DL carrier frequency (absolute radio frequency channel number: ARFCN). PDCCH/PDSCH/PUSCH transmission is possible through the SCell. Supports dynamic activation and deactivation procedures of SCell for battery conservation of UE through MAC layer.

Meanwhile, as the number of NR terminals in the network increases, the issue of insufficient scheduling capacity for NR terminals has been raised. To solve this, cross-carrier scheduling (hereinafter, cross-carrier scheduling) may be used to 'schedule the PDSCH or PUSCH for the PCell or PScell through the PDCCH of the SCell.

Cross-carrier scheduling may mean allocating at least one (eg, PDCCH) of all L1 control channels or L2 control channels for at least one other CC (component carrier) to one CC. A carrier indicator field (CIF) may be used to transmit data information of another CC through the PDCCH of one CC.

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

A 3-bit CIF is added to the downlink control information (DCI) format by applying the cross-carrier scheduling, and the size of the bit is always fixed, and the size of the DCI format can also be fixed regardless of the location.

4 is a diagram illustrating an example of a cross-carrier scheduling method according to an embodiment of the present disclosure.

Referring to 410 of FIG. 4 , PDSCH or PUSCH for two CCs may be scheduled through the PDCCH 401 of one CC.

Also, referring to 420 of FIG. 4 , when a total of four CCs are configured, the PDSCH or PUSCH of each CC may be scheduled using the PDCCHs 421 and 423 of the two CCs.

Each CC may be mapped to a CI (carrier indicator) value for CIF application, which may be transmitted from the base station to the terminal through a dedicated RRC signal as a UE-specific configuration.

Each PDSCH/PUSCH CC may be scheduled from one DL CC. Accordingly, the UE only needs to monitor the PDCCH for the DL CC for each PDSCH/PUSCH CC. The UE may monitor the PDCCH in the DL CC to obtain PUSCH scheduling information in the linked UL carrier. The UE may monitor the PDCCH in the DL CC to obtain PDSCH scheduling information in the linked DL carrier.

Meanwhile, a method for improving cross-carrier scheduling is required in order to improve the scheduling capacity shortage problem, and for this, a method of scheduling PDSCHs for a plurality of cells through one PDCCH may be considered. In this case, the number of cells that can be configured through the PDCCH may be set to a maximum of two, but this is only an example of the present disclosure and the number of cells that can be configured through the PDCCH may be changed.

On the other hand, the present disclosure can be applied to dynamic spectrum sharing (DSS) that enables a carrier to switch to an NR communication system while maintaining an existing LTE communication system by allowing LTE and NR to coexist on the same carrier. In addition, the present disclosure can be applied even when using the NR communication system alone (standalone).

5 is a diagram illustrating an example of setting a control resource set (CORESET) of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 5, in FIG. 5, there are two control regions (control region #1 (CORESET #1) 501) within a bandwidth part 510 of the terminal on the frequency axis and one slot 520 on the time axis. An example in which #2 (CORESET #2) 502) is set is shown. The control regions 501 and 502 may be set in a specific frequency resource 503 within the entire terminal bandwidth portion 510 on the frequency axis. The control regions 501 and 502 may be set with one or more OFDM symbols on the time axis, which may be defined as a control resource set duration (504). In the example of FIG. 5 , the control region #1 501 is set to a control region length of two symbols, and the control region #2 502 is set to a control region length of one symbol.

The control region in 5G described above can be set by the base station to the terminal through higher layer signaling (eg, system information, master information block (MIB), radio resource control (RRC) signaling). Setting the control region to the terminal means to provide the terminal with information such as a control region identity, a frequency position of the control region, and a symbol length of the control region. For example, the information in Table 1 may be included.

[Table 1]

Accordingly, the terminal may monitor the PDCCH in the control region configured by the base station, and may transmit/receive data based on the received control information. Meanwhile, in NR, various types of DCI formats may be provided as shown in Table 2 below for efficient reception of control information of the UE.

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

For example, the base station may use DCI format 1_0, DCI format 1_1, or DCI format 1_2 to allocate (scheduling) the PDSCH for one cell to the terminal. In addition, the base station may use DCI format 1_0, DCI format 1_1, or DCI format 1_2 to allocate PDSCHs for a plurality of cells to the terminal. Alternatively, the base station may use DCI of a different format to allocate PDSCHs for a plurality of cells to the terminal. Although DCI format 1_1 is described as an example in the present disclosure, it is obvious that other DCI formats may be used, and accordingly, some of the following information may be omitted and other information necessary for scheduling a plurality of cells may be included. .

For example, the base station may use DCI format 0_0, DCI format 0_1, or DCI format 0_2 to allocate (scheduling) the PUSCH for one cell to the terminal. In addition, the base station may use DCI format 0_0, DCI format 0_1, or DCI format 0_2 to allocate PUSCHs for a plurality of cells to the terminal. Alternatively, the base station may use a DCI of a different format to allocate PUSCHs for a plurality of cells to the terminal. Although DCI format 0_1 is described as an example in the present disclosure, it is obvious that other DCI formats may be used, and accordingly, some of the following information may be omitted and other information necessary for scheduling a plurality of cells may be included. .

When DCI format 1_0 is transmitted together with CRC scrambled by cell radio network temporary identifier (C-RNTI), configured scheduling RNTI (CS-RNTI), or new-RNTI, it may include at least the following information:

- Identifier for DCI formats(1 bits): Always set to 1 as a DCI format indicator

bits): 주파수 축 자원 할당을 지시하며, DCI format 1_0이 UE specific search space에서 모니터 되는 경우

는 active DL BWP의 크기이며, 이외의 경우

는 initial DL BWP의 크기이다. N_RBG 는 resource block group의 숫자이다. 상세 방법은 상기 주파수 축 자원 할당을 참조한다.- frequency domain resource assignment (N _RBG bits or

bits): indicates frequency axis resource allocation, and when DCI format 1_0 is monitored in the UE specific search space

is the size of the active DL BWP, otherwise

is the size of the initial DL BWP. N _RBG is the number of resource block groups. For a detailed method, refer to the frequency axis resource allocation.

- time domain resource assignment (0~4 bits): indicates time domain resource assignment of PDSCH.

- VRB-to-PRB mapping (1 bit): 0 indicates Non-interleaved, 1 indicates interleaved VRP-to-PRB mapping.

- Modulation and coding scheme (5 bits): indicates the modulation order and coding rate used for PDSCH transmission.

- New data indicator (1 bit): indicates whether the PDSCH is initial transmission or retransmission depending on whether toggle.

- Redundancy version (2 bits): indicates the redundancy version used for PDSCH transmission.

- HARQ process number (4 bits): indicates the HARQ process number used for PDSCH transmission.

- Downlink assignment index (2 bits): DAI indicator

- TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator

- PUCCH resource indicator (3 bits): As a PUCCH resource indicator, it indicates one of eight resources configured as a higher layer.

- PDSCH-to-HARQ_feedback timing indicator (3 bits): As a HARQ feedback timing indicator, it indicates one of eight feedback timing offsets set as a higher layer.

When DCI format 1_1 is transmitted together with CRC scrambled by cell radio network temporary identifier (C-RNTI), configured scheduling RNTI (CS-RNTI), or new-RNTI, it includes at least the following information:

- Identifier for DCI formats (1 bit): Always set to 1 as a DCI format indicator

- Carrier indicator (0 or 3 bits): indicates the CC (or cell) to which the PDSCH allocated by the corresponding DCI is transmitted.

- Bandwidth part indicator (0 or 1 or 2 bits): indicates the BWP through which the PDSCH allocated by the corresponding DCI is transmitted.

는 active DL BWP의 크기이다. 상세 방법은 상기 주파수 축 자원 할당을 참조한다.- Frequency domain resource assignment (determining payload according to the frequency axis resource allocation): indicates frequency axis resource allocation,

is the size of the active DL BWP. For a detailed method, refer to the frequency axis resource allocation.

- Time domain resource assignment (0 ~ 4 bits): indicates time domain resource assignment according to the above description.

- VRB-to-PRB mapping (0 or 1 bit): 0 indicates Non-interleaved, 1 indicates interleaved VRP-to-PRB mapping. It is 0 bit when frequency axis resource allocation is set to resource type 0.

- PRB bundling size indicator (0 or 1 bit): When the upper layer parameter prb-BundlingType is not set or is set to 'static', it is 0 bit, and when it is set to 'dynamic', it is 1 bit.

- Rate matching indicator (0 or 1 or 2 bits): indicates the rate matching pattern.

- ZP CSI-RS trigger (0 or 1 or 2 bits): an indicator for triggering aperiodic ZP CSI-RS.

- For transport block 1:

- Modulation and coding scheme (5 bits): indicates the modulation order and coding rate used for PDSCH transmission.

- New data indicator (1 bit): indicates whether the PDSCH is initial transmission or retransmission depending on whether toggle.

- Redundancy version (2 bits): indicates the redundancy version used for PDSCH transmission.

- For transport block 2:

- Modulation and coding scheme (5 bits): indicates the modulation order and coding rate used for PDSCH transmission.

- New data indicator (1 bit): indicates whether the PDSCH is initial transmission or retransmission depending on whether toggle.

- Redundancy version (2 bits): indicates the redundancy version used for PDSCH transmission.

- HARQ process number (4 bits): indicates the HARQ process number used for PDSCH transmission.

- Downlink assignment index (0 or 2 or 4 bits): DAI indicator

- TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator

- PUCCH resource indicator (3 bits): As a PUCCH resource indicator, it indicates one of eight resources configured as a higher layer.

- PDSCH-to-HARQ_feedback timing indicator (3 bits): As a HARQ feedback timing indicator, it indicates one of eight feedback timing offsets set as a higher layer.

- Antenna port (4 or 5 or 6 bits): indicates DMRS port and CDM group without data.

- Transmission configuration indication (0 or 3 bits): TCI indicator.

- SRS request (2 or 3 bits): SRS transmission request indicator

- CBG transmission information (0 or 2 or 4 or 6 or 8 bits): an indicator indicating whether to transmit code block groups in the allocated PDSCH. 0 means that the CBG is not transmitted, and 1 means that it is transmitted.

- CBG flushing out information (0 or 1 bit): An indicator indicating whether previous CBGs are contaminated. If 0, it means that it may have been contaminated, and if 1, it means that it can be used when receiving retransmission (combinable).

- DMRS sequence initialization (0 or 1 bit): DMRS scrambling ID selection indicator

The maximum number of DCIs of different sizes that the UE can receive per slot in the corresponding cell is 4. The maximum number of DCIs of different sizes scrambled with C-RNTIs that the UE can receive per slot in the corresponding cell is 3.

Meanwhile, information included in the DCI format 1_0 or 1_1 is only an embodiment of the present disclosure, and some information may be omitted or other information may be added. In addition, at least some of the information may be included in a DCI format other than the DCI format 1_0 or 1_1.

Meanwhile, as described above, when scheduling PDCSCHs for a plurality of cells through one PDCCH, a method for determining a DAI value included in control information needs to be newly defined. Meanwhile, in the present disclosure, DAI may be used in combination with a downlink allocation index.

6 is a diagram illustrating a method of determining a DAI when scheduling a PDSCH for one cell through one PDCCH according to the present disclosure.

As described above, the DCI or DCI format transmitted through the PDCCH for scheduling the PDSCH may include DAI. There may be two types of DAI counter DAI (610) and total DAI (620), and the value of each DAI means the following.

).The value of the counter DAI (610) field is {serving cell, PDCCH monitoring time (occasion)} in which DCI formats associated with the current serving cell and PDSCH(s) or SPS PDSCH release up to the current PDCCH monitoring time (occasion) exist. - Means the cumulative number of pair(s). At this time, it is possible to count first in the order of the serving cell index, and then count in the order of the PDCCH monitoring time (occasion) index (A value of the counter downlink assignment indicator (DAI) field in DCI formats denotes the accumulative number of { serving cell, PDCCH monitoring occasion}-pair(s) in which PDSCH reception(s) or SPS PDSCH release associated with the DCI formats is present up to the current serving cell and current PDCCH monitoring occasion, first in ascending order of serving cell index and then in ascending order of PDCCH monitoring occasion index m , where

).

The value of the total DAI (620) field is {serving cell, PDCCH monitoring time (occasion)}-pair(s) in which DCI formats associated with PDSCH(s) or SPS PDSCH release up to the current PDCCH monitoring time (occasion) exist. means the total number of And, the value of the total DAI field may be updated at every PDCCH monitoring occasion (occasion) (The value of the total DAI, when present, in a DCI format denotes the total number of {serving cell, PDCCH monitoring occasion}-pair (s) in which PDSCH reception(s) or SPS PDSCH release associated with DCI formats is present, up to the current PDCCH monitoring occasion m and is updated from PDCCH monitoring occasion to PDCCH monitoring occasion).

Referring to FIG. 6 , four serving cells 601 , 602 , 603 , and 604 may be configured and activated in the UE, and the UE may monitor a PDCCH in each serving cell and receive a PDSCH scheduled through the PDCCH. Values of counter DAI and total DAI included in DCI delivered through PDCCH may be the same as in FIG. 6 . However, the numbers shown in FIG. 6 are numbers to aid understanding, and the actual size of each DAI field may be determined by setting an upper layer, etc., and the actual transmitted DAI value may be determined through a modulo operation. Specifically, the size of the DAI field may be determined according to whether specific information is included or activated (or enabled) in the configuration information transmitted through the higher layer. The specific information may be, for example, information indicating whether total DAI is included. Alternatively, information directly indicating the size of the DAI field may be included in the configuration information. Also, the counter DAI value and the total DAI value may be included in the DAI field. Accordingly, when the total DAI value is not included, the DAI field may be the same as the counter DAI value. When the total DAI value is included, the MSB of a specific bit and the LSB of the specific bit of the DAI field are the counter DAI and the total You can direct DAI. Specifically, the number of bits of DAI is N _DAI , T _D is 2 ^NDAI , the value of Y is PDSCH(s) or PDCCH(s) associated with 'SPS PDSCH release' exists {serving cell, PDCCH monitoring occasion}- When referring to the number of pair(s), the value of the actually transmitted DAI field may be determined as a value of (Y-1) mod T _D + 1.

The UE may perform PDCCH monitoring, and may miss some of the PDCCHs (or PDCCH detection failure or PDCCH lost). 6 shows an example in which the PDCCH 630 is missed in the serving cell #2 603.

Although the UE misses the PDCCH for the serving cell #2, the size of the HARQ-ACK codebook can be determined as 6 according to the total DAI value confirmed through another PDCCH, and the PDCCH including the counter DAI value of 5 was not received. A fifth value of the HARQ-ACK codebook may be set to NACK. Accordingly, the correct HARQ codebook can be determined even when some PDCCHs are not received through the above method.

7 is a diagram illustrating a problem in the case of scheduling PDSCHs for a plurality of cells through one PDCCH according to the present disclosure.

7 illustrates an example of a DAI value in which one PDCCH schedules a PDSCH for a plurality of cells. Referring to FIG. 7 , PDSCHs 712 and 722 for the serving cell 1 and the serving cell 2 may be scheduled through the PDCCH 711 transmitted from the serving cell 1 710 .

The value of the counter DAI field is {serving cell, PDCCH monitoring time (occasion)}-pair ( ), the value of the counter DAI field of the PDCCH transmitted from the serving cell 1 becomes 2.

The value of the total DAI field is {serving cell, PDCCH monitoring time (occasion)} - the total number of pairs (s) in which DCI formats associated with PDSCH (s) or SPS PDSCH release up to the current PDCCH monitoring time (occasion) exist. , so the value of the total DAI field becomes 3.

If the terminal misses the PDCCH 711 transmitted from the serving cell 1 710, the terminal may determine the length of the HARQ-ACK codebook as 3, and the second value of the HARQ-ACK codebook may be set to NACK. . On the other hand, since the base station schedules 4 PDSCHs, the length of the HARQ-ACK codebook can be expected to be 4, and thus a problem may occur.

That is, when one PDCCH schedules a plurality of PDSCHs, if the DAI value is determined based on the PDCCH monitoring time, the correct HARQ-ACK codebook cannot be determined when some PDCCHs are lost (miss or PDCCH detection failure or PDCCH lost). can occur. Accordingly, the present disclosure provides a method for appropriately determining the value of DAI in order to solve the above problems. However, the present disclosure is not limited to a case in which one PDCCH schedules a plurality of PDSCHs. That is, even when one PDCCH schedules one PDSCH, the following method may be equally applied, and in all cases, the DAI value may be determined through the same reference.

To this end, in the present disclosure, the number of PDSCHs may be considered to determine the count DAI value and the total DAI value, and the following method may be specifically considered.

[How to determine the counter DAI field value]

- According to an embodiment of the present disclosure, the value of the counter DAI field may be determined based on the accumulated number of scheduled PDSCHs.

- According to an embodiment of the present disclosure, the value of the counter DAI field is the current serving cell, and the PDCCH up to the current PDCCH monitoring time (occasion) (or {serving cell, PDCCH monitoring time (occasion)} - pair(s)) ) may be determined based on the accumulated number of scheduled PDSCHs.

- According to an embodiment of the present disclosure, if there is a {serving cell, PDCCH monitoring time (occasion)}-pair(s) in which the DCI format associated with the SPS PDSCH release exists, it is additionally accumulated to the accumulated number. The value of the counter DAI field can be determined.

- According to an embodiment of the present disclosure, the value of the counter DAI may be determined based on the number of PDSCHs scheduled by the DCI including the counter DAI field.

- According to an embodiment of the present disclosure, the increment value of the counter DAI value may be determined based on the number of PDSCHs scheduled by the DCI including the counter DAI field. For example, when the DCI schedules one PDSCH, the increment is determined to be 1, when the DCI schedules two PDSCHs, the increment is determined to be 2, and the DCI schedules n PDSCHs. In this case, the increase value may be determined as n.

- According to an embodiment of the present disclosure, the increment value of the counter DAI value may be determined based on the number of serving cells in which the PDSCH scheduled by the DCI including the counter DAI field is transmitted. For example, when the DCI schedules one PDSCH to one serving cell, the increment is determined to be 1, and when the DCI schedules two PDSCHs to two serving cells, the increment is determined to be 2. and, when the DCI schedules n PDSCHs to n serving cells, the increase may be determined to be n.

- According to an embodiment of the present disclosure, the increment value of the counter DAI value may be determined based on a transmission method of data corresponding to the PDSCH scheduled by the DCI including the counter DAI field. Alternatively, the method may be expressed that the increment value of the counter DAI value is determined based on whether data transmitted through a plurality of PDSCHs scheduled by one DCI are the same. For example, when data transmitted through PDSCHs scheduled by the DCI are different data, an increment value of the counter DAI value is determined based on the number of PDSCHs, and data transmitted through PDSCHs scheduled by the DCI is In the case of the same data, the increment value may be determined to be 1. According to an embodiment of the present disclosure, the 'total DAI' value may be determined based on the 'data transmission method' corresponding to the PDSCH or the 'identity of data transmitted through a plurality of PDSCHs'. That is, when the same data is transmitted through a plurality of PDSCHs transmitted from a plurality of serving cells, the value of the 'total DAI' field may be determined so that the HARQ-ACK feedback information in the corresponding HARQ-ACK codebook is 1 bit. For example, 4 serving cells (serving cell 0, serving cell 1, serving cell 2, serving cell 3) are configured and activated, and 4 PDSCHs are transmitted from each of the 4 serving cells, which are scheduled through one PDCCH. When data transmitted through the PDSCH of the serving cell 1 and the PDSCH of the serving cell 2 are the same (repeated transmission, etc.), according to the above embodiment, the counter DAI value is increased by 1, and the total DAI value may be determined to be 3.

- According to an embodiment of the present disclosure, the size of the HARQ-ACK feedback associated with the DCI may be determined. For example, when the increment of the counter DAI value is 1 and the number of TBs associated with the PDSCH is 1, the corresponding HARQ-ACK feedback is 1 bit, and when the number of TBs associated with the PDSCH is 2, corresponding The HARQ-ACK feedback may be 2 bits. When the increment of the counter DAI value is 2, each of the TBs associated with the PDSCHs is 1, the corresponding HARQ-ACK feedback is each 1 bit, and when there are two TBs associated with the PDSCHs, the corresponding HARQ-ACK feedback is corresponding Each HARQ-ACK feedback may be 2 bits.

- According to an embodiment of the present disclosure, the position in the HARQ-ACK codebook of each HARQ-ACK feedback information for a plurality of PDSCHs indicated to a plurality of serving cells by one PDCCH is in the index of the serving cells. can be determined by The index of the HARQ-ACK feedback information for the PDSCH transmitted to the serving cell having the low serving cell index is smaller than the index of the HARQ-ACK feedback information for the PDSCH transmitted to the serving cell having the high serving cell index. .

- According to an embodiment of the present disclosure, the value (Y) of the counter DAI determined in one of the above-described embodiments or a combination of the above-described embodiments is as follows according to the bitwidth (N ^DL _C-DAI ) allocated to the counter DAI The same operation is performed, and the result of the operation may be included in the counter DAI field in the actual DCI.

When the N ^DL _C-DAI value is 2, it may be determined as shown in the table below.

[Table 3]

When the N ^DL _C-DAI value is 1, it may be determined as shown in the table below.

[Table 4]

- According to an embodiment of the present disclosure, the above embodiments may be applied when the UE monitors a PDCCH for scheduling a plurality of (e.g. two) PDSCHs.

- According to an embodiment of the present disclosure, the above embodiments may be applied to other channels (e.g. PSSCH) in the same manner.

- According to an embodiment of the present disclosure, the increase value of the counter DAI or the counter DAI value may be determined by a combination of the above embodiments.

[How to determine total DAI field value]

- According to an embodiment of the present disclosure, the value of the total DAI field may be determined based on the total number of scheduled PDSCHs.

- According to an embodiment of the present disclosure, the value of the total DAI field is the PDSCH scheduled through the PDCCH (or {serving cell, PDCCH monitoring time (occasion)}-pair(s)) up to the current PDCCH monitoring time (occasion). may be determined based on the total number of . And the value of the total DAI field may be updated at every PDCCH monitoring occasion.

- According to an embodiment of the present disclosure, if there is a {serving cell, PDCCH monitoring time (occasion)}-pair(s) in which the DCI format associated with the SPS PDSCH release exists, it is added to the total number to total The value of the DAI field can be determined.

- According to an embodiment of the present disclosure, the calculation as shown in the table below is performed for the total DAI value (Y) determined in one of the above-described embodiments or a combination of the above-described embodiments, and the result of the operation It can be included in the total DAI field in this actual DCI.

[Table 5]

- According to an embodiment of the present disclosure, the above embodiments may be applied when the UE monitors a PDCCH for scheduling a plurality of (e.g. two) PDSCHs.

- According to an embodiment of the present disclosure, the above embodiments may be applied to other channels (e.g. PSSCH) in the same manner.

- According to an embodiment of the present disclosure, the value of total DAI may be determined by a combination of the above embodiments.

According to an embodiment of the present disclosure, the UE may determine the size of the HARQ-ACK feedback message by using at least “the value of total DAI based on the total number of scheduled PDSCHs”.

Specifically, the UE utilizes the value of the counter DAI based on the accumulated number of scheduled PDSCHs and the value of the total DAI based on the total number of scheduled PDSCHs, so that the UE selects a specific {serving cell, PDCCH monitoring time (occasion)}-pair ( ), it is possible to recognize (recognize, identify) that the PDCCH is missed. Accordingly, the UE may determine the HARQ-ACK feedback information corresponding to the PDCCH miss as NACK according to the result of the PDCCH miss recognition.

8 is a diagram illustrating a method of determining a DAI value according to an embodiment of the present disclosure.

Referring to FIG. 8 , the value of the counter DAI field may be determined based on the accumulated number of scheduled PDSCHs, and the value of the total DAI field may be determined based on the total number of scheduled PDSCHs. In detail, the method of determining the counter DAI field value and the total DAI field value is the same as described above, and will be omitted below.

Since four PDSCHs (801, 811, 821, 831) are scheduled in four serving cells, the value of the total DACI field of DCI included in PDCCHs transmitted from serving cell #0, serving cell #1, and serving cell #3 is can be 4. In the serving cell #1, since the DCI transmitted through the PDCCH 810 schedules two PDSCHs, the total number of PDSCHs accumulated until the PDCCH monitoring time of the serving cell #1 is three, and the The counter DAI value of the DCI included in the PDCCH 810 may be 3.

The UE may determine the length of the HARQ-ACK codebook as 4 according to the value of the total DACI field, and may determine the second and third values of the HARQ-ACK codebook as NACK.

In this drawing, the case of scheduling a plurality of PDSCHs through one PDCCH has been described as an example, but as described above, the present disclosure is not limited thereto. That is, even when one PDCCH schedules one PDSCH, the following method may be equally applied, and in all cases, the DAI value may be determined through the same reference.

9 is a diagram illustrating an operation of a terminal according to an embodiment of the present disclosure.

Referring to FIG. 9 , the terminal may receive configuration information including information on the control region in step S910 . Specific details of the information on the control area are the same as those described with reference to FIG. 5 . In addition, the configuration information may be received by being included in higher layer signaling (eg, RRC message).

The terminal may receive DCI through the PDCCH based on the information on the control region in step S920. The DCI may include the above-described DAI field. The DAI field may include a total DAI value and a counter DAI value. However, the DAI field may include at least one of a total DAI value and a counter DAI value. For example, when the configuration information received through higher layer signaling does not include information indicating whether total DAI is included or is not activated (disabled), the DAI field may include only the counter DAI value. Accordingly, the bit length of the DAI field may be determined based on configuration information received through higher layer signaling.

In addition, the total DAI value and the counter DAI value may be determined based on the PDSCH scheduled as described above. For example, the counter DAI value is based on the number of PDSCHs scheduled up to the PDCCH monitoring time (or current PDCCH monitoring time, current monitoring occasion) and the serving cell (or current serving cell, current serving cell) corresponding to the PDCCH. may be determined, and the total DAI may be determined based on the number of PDSCHs scheduled up to the PDCCH monitoring time (or current PDCCH monitoring time, current monitoring occsasion). However, this is an embodiment of the present disclosure, and may be determined based on the above-described method of determining the counter DAI value and the method of determining the total DAI value.

The counter DAI value may be first counted in the ascending order of the serving cell index, and then counted in the ascending order of the PDCCH monitoring time index. Also, the total DAI value may be updated at every PDCCH monitoring time point.

Meanwhile, the DCI may schedule a PDSCH for one serving cell or a PDSCH for a plurality of serving cells. In this case, when the base station schedules PDSCHs for a plurality of serving cells through the DCI, an increase value of the counter DAI value may be determined according to whether data transmitted through the PDSCHs are the same. For example, when the data transmitted through the PDSCH are the same, the increment value may be 1, and when the data are different, the increment value may be determined based on the number of PDSCHs scheduled through the DCI.

In addition, the UE may receive data through the PDSCH scheduled based on the DCI in step S930. In addition, the terminal may determine the HARQ-ACK codebook based on the data reception result and the DAI field in step S940 and transmit it to the base station.

Specifically, when data is not received through the scheduled PDSCH (when reception or decoding fails), the UE may determine the value of the HARQ-ACK codebook as NACK.

Also, the UE may determine the HARQ-ACK codebook based on the total DAI and counter DAI values included in the DAI field. Specifically, the UE may determine the length of the HARQ-ACK codebook based on the total DAI value. In addition, when there is a DCI that has not been received until the current PDCCH monitoring time, the UE may determine a value corresponding to the counter DAI value of the not received DCI in the HARQ-ACK codebook as a negative acknowledgment (NACK). By determining the DAI through the above-described method and determining the HARQ-ACK codebook, smooth communication can be performed in the case of scheduling one PDSCH through one DCI and scheduling a plurality of PDSCHs through one DCI. have.

10 is a diagram illustrating an operation of a base station according to an embodiment of the present disclosure.

Referring to FIG. 10 , the base station may transmit configuration information including information on the control region in step S1010. Specific details of the information on the control area are the same as those described with reference to FIG. 5 . In addition, the configuration information may be transmitted while being included in higher layer signaling (eg, RRC message).

The base station may transmit DCI through the PDCCH based on the information on the control region in step S1020. The DCI may include the above-described DAI field. The DAI field may include a total DAI value and a counter DAI value. However, the DAI field may include at least one of a total DAI value and a counter DAI value. For example, when the configuration information received through higher layer signaling does not include information indicating whether total DAI is included or is not activated (disabled), the DAI field may include only the counter DAI value. Accordingly, the bit length of the DAI field may be determined based on configuration information received through higher layer signaling.

In addition, the total DAI value and the counter DAI value may be determined based on the PDSCH scheduled as described above. For example, the counter DAI value is based on the number of PDSCHs scheduled up to the PDCCH monitoring time (or current PDCCH monitoring time, current monitoring occasion) and the serving cell (or current serving cell, current serving cell) corresponding to the PDCCH. may be determined, and the total DAI may be determined based on the number of PDSCHs scheduled up to the PDCCH monitoring time (or current PDCCH monitoring time, current monitoring occsasion). However, this is an embodiment of the present disclosure, and may be determined based on the above-described method of determining the counter DAI value and the method of determining the total DAI value.

The counter DAI value may be first counted in the ascending order of the serving cell index, and then counted in the ascending order of the PDCCH monitoring time index. Also, the total DAI value may be updated at every PDCCH monitoring time point.

Meanwhile, the DCI may schedule a PDSCH for one serving cell or a PDSCH for a plurality of serving cells. In this case, when the base station schedules PDSCHs for a plurality of serving cells through the DCI, an increase value of the counter DAI value may be determined according to whether data transmitted through the PDSCHs are the same. For example, when the data transmitted through the PDSCH are the same, the increment value may be 1, and when the data are different, the increment value may be determined based on the number of PDSCHs scheduled through the DCI.

In addition, the base station may transmit data through the PDSCH scheduled based on the DCI in step S1030. In addition, the base station may receive the HARQ-ACK codebook determined based on the data reception result and the DAI field in step S1040.

Specifically, when data is not received by the terminal through the scheduled PDSCH (when the terminal fails to receive or decode), the value of the HARQ-ACK codebook may be determined as NACK.

Also, the HARQ-ACK codebook may be determined based on the total DAI and counter DAI values included in the DAI field. Specifically, the length of the HARQ-ACK codebook may be determined based on the total DAI value. In addition, when there is a DCI that has not been received until the current PDCCH monitoring time, a value corresponding to the counter DAI value of the not received DCI in the HARQ-ACK codebook may be determined as a negative acknowledgment (NACK).

11 is a diagram illustrating a structure of a terminal according to an embodiment of the present disclosure.

Referring to FIG. 11 , the terminal may include a transceiver 1110 , a control unit 1120 , and a storage unit 1130 . In the present invention, the controller may be defined as a circuit or an application specific integrated circuit or at least one processor.

The transceiver 1110 may transmit/receive a signal to/from another network entity. The transceiver 1110 may receive, for example, configuration information including information on the control region from the base station. Also, the transceiver 1110 may receive control information from the base station and receive data based thereon. In addition, the transceiver 1110 may transmit the determined HARQ codebook information to the base station.

The controller 1120 may control the overall operation of the terminal according to the embodiment proposed in the present invention. For example, the controller 1120 may control a signal flow between blocks to perform an operation according to the above-described flowchart. For example, the controller 1120 receives the DCI through the PDCCH, and determines the HARQ codebook based on whether data is received through the DAI field included in the DCI and the PDSCH scheduled by the DCI. You can control the behavior suggested by . The above-described operation of the terminal may be controlled by the controller 1120 , and detailed description thereof will be omitted.

The storage unit 1130 may store at least one of information transmitted/received through the transceiver 1110 and information generated through the control unit 1120 .

12 is a diagram illustrating a structure of a base station according to an embodiment of the present disclosure.

Referring to FIG. 12 , the base station may include a transceiver 1210 , a controller 1220 , and a storage 1230 . In the present invention, the controller may be defined as a circuit or an application specific integrated circuit or at least one processor.

The transceiver 1210 may transmit/receive signals to and from other network entities. The transceiver 1210 may transmit, for example, configuration information including information on the control region to the terminal. Also, the transceiver 1210 may transmit control information to the terminal and transmit data based thereon. In addition, the transceiver 1210 may receive the determined HARQ codebook information from the terminal.

The controller 1220 may control the overall operation of the base station according to the embodiment proposed in the present invention. For example, the controller 1220 may control a signal flow between blocks to perform an operation according to the above-described flowchart. For example, the controller 1220 transmits a DCI through the PDCCH according to an embodiment of the present disclosure, and the HARQ determined based on whether data is received through the DAI field included in the DCI and the PDSCH scheduled by the DCI. It is possible to control the operation proposed in the present invention for receiving the codebook. The above-described operation of the terminal may be controlled by the controller 1220 , and detailed description thereof will be omitted.

The storage unit 1230 may store at least one of information transmitted and received through the transceiver 1210 and information generated through the control unit 1220 .

Accordingly, according to various embodiments of the present disclosure, in a method performed by a terminal in a communication system, the method comprising: receiving configuration information including information on a control region of a serving cell from a base station through higher layer signaling; receiving downlink control information (DCI) including a downlink assignment index (DAI) field from the base station through a physical downlink control channel (PDCCH) based on the information on the control region; receiving data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and determining a hybrid automatic repeat request (HARQ) codebook based on the data reception result and the DAI field, wherein the HARQ codebook is included in the DAI field, the PDCCH monitoring time corresponding to the PDCCH and the serving It is characterized in that it is determined based on a counter DAI value determined based on the number of PDSCHs scheduled up to the cell and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a method performed by a base station in a communication system, the method includes: transmitting configuration information including information on a control region of a serving cell to a terminal through higher layer signaling; transmitting downlink control information (DCI) including a downlink assignment index (DAI) field to the terminal through a physical downlink control channel (PDCCH) based on the information on the control region; transmitting data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and receiving, from the terminal, a hybrid automatic repeat request (HARQ) codebook determined based on the data reception result and the DAI field, wherein the HARQ codebook is included in the DAI field. PDCCH monitoring corresponding to the PDCCH It is characterized in that it is determined based on a counter DAI value determined based on a time point and the number of PDSCHs scheduled up to the serving cell and a total DAI value determined based on the number of PDSCHs scheduled up to the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a terminal in a communication system, a transceiver; And it is connected to the transceiver and receives configuration information including information on the control region of the serving cell from the base station through higher layer signaling, and based on the information on the control region, DAI through a physical downlink control channel (PDCCH) Receives downlink control information (DCI) including a (downlink assignment index) field from the base station, and receives data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI, and the data reception result and a control unit for determining a hybrid automatic repeat request (HARQ) codebook based on the DAI field, wherein the HARQ codebook includes a PDCCH monitoring time corresponding to the PDCCH included in the DAI field and a PDSCH scheduled up to the serving cell It is characterized in that it is determined based on a counter DAI value determined based on the number of , and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

In addition, according to various embodiments of the present disclosure, in a base station in a communication system, a transceiver; and connected to the transceiver, transmits configuration information including information on the control region of the serving cell to the terminal through higher layer signaling, and based on the information on the control region, DAI through a physical downlink control channel (PDCCH) Transmits downlink control information (DCI) including a (downlink assignment index) field to the terminal, and transmits data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI, and the data reception result and a controller for receiving, from the terminal, a hybrid automatic repeat request (HARQ) codebook determined based on the DAI field, wherein the HARQ codebook is included in the DAI field, the PDCCH monitoring time corresponding to the PDCCH and the serving cell It is characterized in that it is determined based on a counter DAI value determined based on the number of PDSCHs scheduled until , and a total DAI value determined based on the number of PDSCHs scheduled until the PDCCH monitoring time point.

On the other hand, in the drawings for explaining the method of the present invention, the order of description does not necessarily correspond to the order of execution, and the precedence relationship may be changed or may be executed in parallel.

Alternatively, the drawings for explaining the method of the present invention may omit some components and include only some components within a range that does not impair the essence of the present invention.

In addition, the method of the present invention may be implemented in a combination of some or all of the contents contained in each embodiment within a range that does not impair the essence of the invention.

Claims (20)

A method performed by a terminal in a communication system, comprising:
Receiving configuration information including information on the control region of the serving cell through higher layer signaling from the base station;
receiving downlink control information (DCI) including a downlink assignment index (DAI) field from the base station through a physical downlink control channel (PDCCH) based on the information on the control region;
receiving data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and
determining a hybrid automatic repeat request (HARQ) codebook based on the data reception result and the DAI field,
The HARQ codebook includes a counter DAI value determined based on the number of PDSCHs scheduled up to the serving cell and the PDCCH monitoring time corresponding to the PDCCH included in the DAI field, and the number of PDSCHs scheduled until the PDCCH monitoring time. A method, characterized in that determined based on the determined total DAI value. According to claim 1,
Determining the HARQ codebook comprises:
determining the length of the HARQ codebook based on the total DAI value; and
The method further comprising the step of determining, as a negative acknowledgment (NACK), a value corresponding to a counter DAI value of the not received DCI in the HARQ codebook when there is a DCI that has not been received until the PDCCH monitoring time point. According to claim 1,
The count DAI value is counted in the ascending order of the serving cell index and then counted in the ascending order of the PDCCH monitoring time index,
The total DAI value is updated at every PDCCH monitoring time. According to claim 1,
The bit length of the DAI field is determined based on the configuration information,
The DCI method, characterized in that it includes resource allocation information for scheduling the PDSCH for at least one serving cell. According to claim 1,
When the DCI schedules PDSCHs for a plurality of serving cells,
The increase value of the counter DAI value is determined according to whether data transmitted through the PDSCH are the same,
When the data transmitted through the PDSCH are the same, the increment value is 1. A method performed by a base station in a communication system, comprising:
transmitting configuration information including information on the control region of the serving cell to the terminal through higher layer signaling;
transmitting downlink control information (DCI) including a downlink assignment index (DAI) field to the terminal through a physical downlink control channel (PDCCH) based on the information on the control region;
transmitting data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI; and
Receiving a hybrid automatic repeat request (HARQ) codebook determined based on the data reception result and the DAI field from the terminal,
The HARQ codebook includes a counter DAI value determined based on the number of PDSCHs scheduled up to the serving cell and the PDCCH monitoring time corresponding to the PDCCH included in the DAI field, and the number of PDSCHs scheduled until the PDCCH monitoring time. A method, characterized in that determined based on the determined total DAI value. 7. The method of claim 6,
The length of the HARQ codebook is determined based on the total DAI value,
If there is a DCI that has not been received until the PDCCH monitoring time point, a value corresponding to a counter DAI value of the not received DCI in the HARQ codebook is determined as a negative acknowledgment (NACK). 7. The method of claim 6,
The count DAI value is first counted in ascending order of the serving cell index and then counted in ascending order of the PDCCH monitoring time index,
The total DAI value is updated at every PDCCH monitoring time. 7. The method of claim 6,
The bit length of the DAI field is determined based on the configuration information,
The DCI method, characterized in that it includes resource allocation information for scheduling the PDSCH for at least one serving cell. 7. The method of claim 6,
When the DCI schedules PDSCHs for a plurality of serving cells,
The increase value of the counter DAI value is determined according to whether data transmitted through the PDSCH are the same,
When the data transmitted through the PDSCH are the same, the increment value is 1. In a terminal in a communication system,
transceiver; and
connected to the transceiver,
Receive configuration information including information on the control region of the serving cell through higher layer signaling from the base station,
Receiving downlink control information (DCI) including a downlink assignment index (DAI) field from the base station through a physical downlink control channel (PDCCH) based on the information on the control region,
Receive data from the base station through a physical downlink shared channel (PDSCH) scheduled based on the DCI,
A control unit for determining a hybrid automatic repeat request (HARQ) codebook based on the data reception result and the DAI field,
The HARQ codebook includes a counter DAI value determined based on the number of PDSCHs scheduled up to the serving cell and the PDCCH monitoring time corresponding to the PDCCH included in the DAI field, and the number of PDSCHs scheduled until the PDCCH monitoring time. Terminal, characterized in that determined based on the determined total DAI value. 12. The method of claim 11,
The control unit is
Determine the length of the HARQ codebook based on the total DAI value,
When there is a DCI that has not been received until the PDCCH monitoring time, a value corresponding to a counter DAI value of the not received DCI in the HARQ codebook is determined as a negative acknowledgment (NACK). 12. The method of claim 11,
The count DAI value is first counted in ascending order of the serving cell index and then counted in ascending order of the PDCCH monitoring time index,
The total DAI value is updated at every PDCCH monitoring time point. 12. The method of claim 11,
The bit length of the DAI field is determined based on the configuration information,
The DCI terminal, characterized in that it includes resource allocation information for scheduling the PDSCH for at least one serving cell. 12. The method of claim 11,
When the DCI schedules PDSCHs for a plurality of serving cells,
The increase value of the counter DAI value is determined according to whether data transmitted through the PDSCH are the same,
When the data transmitted through the PDSCH are the same, the increment is 1. In a base station in a communication system,
transceiver; and
connected to the transceiver,
Transmitting configuration information including information on the control region of the serving cell to the terminal through higher layer signaling,
Transmitting downlink control information (DCI) including a downlink assignment index (DAI) field to the terminal through a physical downlink control channel (PDCCH) based on the information on the control region,
Transmitting data to the terminal through a physical downlink shared channel (PDSCH) scheduled based on the DCI,
a control unit configured to receive, from the terminal, a hybrid automatic repeat request (HARQ) codebook determined based on the data reception result and the DAI field,
The HARQ codebook includes a counter DAI value determined based on the number of PDSCHs scheduled up to the serving cell and the PDCCH monitoring time corresponding to the PDCCH included in the DAI field, and the number of PDSCHs scheduled until the PDCCH monitoring time. Base station, characterized in that determined based on the determined total DAI value. 17. The method of claim 16,
The length of the HARQ codebook is determined based on the total DAI value,
When there is a DCI that has not been received until the PDCCH monitoring time point, a value corresponding to a counter DAI value of the not received DCI in the HARQ codebook is determined as a negative acknowledgment (NACK). 17. The method of claim 16,
The count DAI value is first counted in ascending order of the serving cell index and then counted in ascending order of the PDCCH monitoring time index,
The total DAI value is updated at every PDCCH monitoring time point. 17. The method of claim 16,
The bit length of the DAI field is determined based on the configuration information,
The DCI is a base station, characterized in that it includes resource allocation information for scheduling the PDSCH for at least one serving cell. 17. The method of claim 16,
When the DCI schedules PDSCHs for a plurality of serving cells,
The increase value of the counter DAI value is determined according to whether data transmitted through the PDSCH are the same,
When the data transmitted through the PDSCH are the same, the increment is 1.

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