CN118120170A

CN118120170A - Method, apparatus and system for allocating HARQ process numbers for downlink and uplink transmissions in a wireless communication system

Info

Publication number: CN118120170A
Application number: CN202280069010.3A
Authority: CN
Inventors: 卢珉锡; 石根永; 孙周亨; 郭真三
Original assignee: Wilus Institute of Standards and Technology Inc
Current assignee: Wilus Institute of Standards and Technology Inc
Priority date: 2021-10-13
Filing date: 2022-10-13
Publication date: 2024-05-31

Abstract

A method for a terminal to transmit a Physical Uplink Shared Channel (PUSCH) to a base station in a wireless communication system is disclosed. The terminal may: receiving Radio Resource Control (RRC) configuration information related to configuration of a slot from a base station; and receiving a Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) of a plurality of Physical Uplink Shared Channels (PUSCHs) scheduled for the terminal from the base station.

Description

Method, apparatus and system for allocating HARQ process numbers for downlink and uplink transmissions in a wireless communication system

Technical Field

The present invention relates to a wireless communication system. In particular, the present invention relates to methods, devices and systems for determining and transmitting resources of downlink and uplink shared channels.

Background

After commercialization of the fourth generation (4G) communication system, efforts are being made to develop a new fifth generation (5G) communication system in order to meet the increasing demand for wireless data services. The 5G communication system is called a super 4G network communication system, a LTE-after system, or a New Radio (NR) system. In order to achieve a high data transmission rate, 5G communication systems include systems that operate using a millimeter wave (mmWave) band of 6GHz or higher, and include communication systems that operate using a band of 6GHz or lower in terms of ensuring coverage, so that implementation in base stations and terminals is under consideration.

The third generation partnership project (3 GPP) NR system improves the spectral efficiency of the network and enables communication providers to provide more data and voice services over a given bandwidth. Thus, 3GPP NR systems are designed to meet the demand for high-speed data and media transmission in addition to supporting a large amount of voice. The advantages of NR systems are higher throughput and lower latency on the same platform, support for Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD), and low operating costs due to enhanced end user environments and simple architecture.

For more efficient data processing, dynamic TDD of NR systems may use a method for changing the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols that can be used in uplink and downlink according to the data traffic direction of cell users. For example, when the downlink traffic of a cell is greater than the uplink traffic, the base station may allocate a plurality of downlink OFDM symbols to a slot (or subframe). Information about the slot configuration should be transmitted to the terminal.

In order to mitigate path loss of radio waves and increase transmission distance of radio waves in mmWave frequency band, in 5G communication systems, beamforming, massive multiple input/output (massive MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, hybrid beamforming combining analog beamforming and digital beamforming, and massive antenna techniques are discussed. Further, for network improvement of the system, in the 5G communication system, technology development is being performed regarding an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra dense network, device-to-device communication (D2D), vehicle-to-everything communication (V2X), a wireless backhaul, a non-terrestrial network communication (NTN), a mobile network, cooperative communication, coordinated multipoint (CoMP), interference cancellation, and the like. Furthermore, in the 5G system, hybrid FSK with QAM modulation (FQAM) and Sliding Window Superposition Coding (SWSC) as Advanced Coding Modulation (ACM) schemes, and Filter Bank Multicarrier (FBMC), non-orthogonal multiple access (NOMA) and Sparse Code Multiple Access (SCMA) as advanced connection techniques are being developed.

Meanwhile, in human-centric connection networks where humans generate and consume information, the internet has evolved into an internet of things (IoT) network that exchanges information between distributed components such as objects. Internet of everything (IoE) technology combining IoT technology with big data processing technology through a connection with a cloud server is also emerging. In order to implement IoT, technical elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, so that technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) have been studied in recent years to connect between objects. In an IoT environment, intelligent Internet Technology (IT) services can be provided that collect and analyze data generated from networked objects to create new value in human life. Through the fusion and mixing of existing Information Technology (IT) and various industries, ioT can be applied in fields such as smart homes, smart buildings, smart cities, smart cars or networked cars, smart grids, healthcare, smart appliances and advanced medical services.

Accordingly, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M), and Machine Type Communications (MTC) are implemented through technologies such as beamforming, MIMO, and array antennas. The application of the cloud RAN as the big data processing technology described above is an example of a fusion of 5G technology and IoT technology. In general, a mobile communication system is developed to provide a voice service while ensuring activities of users.

However, the mobile communication system is gradually expanding not only a voice service but also a data service, and has now been developed to the extent of providing a high-speed data service. However, in the mobile communication system currently providing services, a more advanced mobile communication system is required due to a resource shortage phenomenon and high-speed service demands of users.

Disclosure of Invention

Technical problem

An aspect of the present invention is to provide a method of determining resources for a downlink shared channel and an uplink shared channel and allocating HARQ process numbers in a wireless communication system, particularly a cellular wireless communication system, and an apparatus therefor.

Solution to the problem

A terminal for transmitting a Physical Uplink Shared Channel (PUSCH) in a wireless communication system may include: a communication module; and a processor configured to control the communication module, wherein the processor is configured to: receiving Radio Resource Control (RRC) configuration information related to configuration of a slot from a base station; and receiving a Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) of a plurality of Physical Uplink Shared Channels (PUSCHs) scheduled for the terminal from the base station, the DCI indicating a hybrid automatic repeat request (HARQ) process number of a first PUSCH among the plurality of PUSCHs, and increasing HARQ process numbers of PUSCHs included in the plurality of PUSCHs as compared to HARQ process numbers of previous PUSCHs of the PUSCHs according to whether symbols of slots of the scheduled PUSCHs overlap with symbols indicated as downlink or flexible by RRC configuration information.

In addition, in the present invention, when a symbol of a slot in which PUSCH is scheduled is indicated as an uplink symbol through RRC configuration information, the HARQ process number of the PUSCH is obtained by increasing the HARQ process number of the previous PUSCH by "1".

In addition, in the present invention, when a symbol of a slot in which PUSCH is scheduled overlaps with a downlink symbol indicated by RRC configuration information, PUSCH is not transmitted on the slot.

In addition, in the present invention, the HARQ process number of PUSCH is not increased compared to that of the previous PUSCH.

In addition, in the present invention, when a symbol of a slot in which a next PUSCH of PUSCHs among a plurality of PUSCHs is scheduled is indicated as an uplink symbol through RRC configuration information, the HARQ process number of the next PUSCH is obtained by increasing the HARQ process number of the previous PUSCH by "1".

Further, in the present invention, when the symbol of the slot in which the PUSCH is scheduled overlaps with the flexible symbol indicated by the RRC configuration information, the HARQ process number of the PUSCH is obtained by increasing the HARQ process number of the previous PUSCH by "1" according to whether or not a specific signal is configured on the flexible symbol.

In addition, in the present invention, the specific signal is a synchronization signal/PBCH block (SSB) indicated by SSBpositioninburst which is a higher layer parameter of RRC configuration information.

In addition, in the present invention, when a specific signal is not configured on a flexible symbol, the HARQ process number of PUSCH is obtained by increasing the HARQ process number of the previous PUSCH by "1".

In addition, in the present invention, the HARQ process number of the PUSCH is obtained by increasing the HARQ process number of the previous PUSCH by "1", whether or not the symbol of the slot in which the PUSCH is scheduled is indicated as uplink, downlink, or flexible by a Slot Format Indicator (SFI).

Further, in the present invention, the symbol of the slot in which the first PUSCH is transmitted and the symbol indicated as downlink by the RRC configuration information do not overlap.

In addition, the present invention provides a terminal for receiving a Physical Downlink Shared Channel (PDSCH) in a wireless communication system, which may include: a communication module; and a processor, wherein the processor is configured to: receiving Radio Resource Control (RRC) configuration information related to configuration of a slot from a base station; and receiving a Physical Downlink Control Channel (PDCCH) from the base station, the Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) scheduling a plurality of physical downlink shared channels (PUSCHs) for the terminal, the DCI indicating a hybrid automatic repeat request (HARQ) process number of a first PDSCH among the plurality of PDSCHs, and HARQ process numbers of PDSCHs included in the plurality of PDSCHs are increased as compared to HARQ process numbers of previous PDSCHs of the PDSCHs according to whether symbols of slots of the scheduled PDSCH overlap with symbols indicated as uplink or flexible by RRC configuration information.

Further, in the present invention, when the symbol of the slot of the scheduling PDSCH is indicated as a downlink symbol by RRC configuration information, the HARQ process number of the PDSCH is obtained by increasing the HARQ of the previous PDSCH by "1".

In addition, in the present invention, when a symbol of a slot in which a PDSCH is scheduled overlaps with an uplink symbol indicated by RRC configuration information, the PDSCH is not received on the slot.

In addition, in the present invention, the HARQ process number of the PDSCH is not increased compared to that of the previous PDSCH.

In addition, in the present invention, when a symbol of a slot where a next PDSCH of a plurality of PDSCH is scheduled is indicated as a downlink symbol by RRC configuration information, the HARQ process number of the next PDSCH is obtained by increasing the HARQ process number of the previous PDSCH by "1".

In addition, in the present invention, when the symbol of the slot of the scheduled PDSCH overlaps with the flexible symbol indicated by the RRC configuration information, the HARQ process number of the PDSCH is obtained by increasing the HARQ process number of the previous PDSCH by "1".

In addition, in the present invention, the HARQ process number of the PDSCH is obtained by increasing the HARQ process number of the previous PDSCH by "1", whether or not the symbol of the slot in which the PDSCH is scheduled is indicated as uplink, downlink, or flexible by a Slot Format Indicator (SFI).

In the present invention, the symbol of the slot in which the first PDSCH is transmitted does not overlap with the symbol indicated as uplink by the RRC configuration information.

In addition, the present invention provides a method comprising: receiving Radio Resource Control (RRC) configuration information related to configuration of a slot from a base station; and receiving a Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) for scheduling a plurality of PUSCHs of the terminal from the base station, wherein the DCI indicates a hybrid automatic repeat request (HARQ) process number of a first PUSCH among the plurality of PUSCHs, and increasing the HARQ process number of a PUSCH included in the plurality of PUSCHs as compared to the HARQ process number of a previous PUSCH of the PUSCH according to whether a symbol of a slot for scheduling the PUSCH overlaps with a symbol indicated as downlink or flexible by RRC configuration information.

Advantageous effects of the invention

According to the embodiments of the present invention, a terminal can efficiently determine resources for data and control information to be transmitted through an uplink shared channel and efficiently transmit data and uplink control information to a base station through the uplink shared channel.

In addition, according to the embodiments of the present invention, a terminal can efficiently determine resources for data and control information to be received through a downlink shared channel and efficiently receive the downlink shared channel from a base station.

In addition, according to the present invention, in the case of scheduling a plurality of PUSCHs or a plurality of PDSCH, HARQ process numbers thereof can be efficiently configured.

In addition, according to the present invention, in the case of scheduling a plurality of PDSCHs, when a symbol of a slot of each of the plurality of PDSCHs is scheduled to overlap with a symbol indicated as flexible by RRC configuration information, HARQ process numbers are increased regardless of PDSCH reception, so that ambiguity between a terminal and a base station depending on whether the terminal detects SFI can be resolved.

In addition, according to the present invention, in the case of scheduling a plurality of PUSCHs, when a symbol of a slot of each of the plurality of PUSCHs is scheduled to overlap with a symbol indicated as flexible by RRC configuration information, HARQ process numbers are increased only in consideration of whether reception of a specific signal (e.g., synchronization signal/PBCH block (SSB)) is configured in the symbol, regardless of PUSCH transmission, so that ambiguity between a terminal and a base station depending on whether the terminal detects an SFI can be eliminated.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

Drawings

Fig. 1 illustrates an example of a radio frame structure used in a wireless communication system.

Fig. 2 illustrates an example of a Downlink (DL)/Uplink (UL) slot structure in a wireless communication system.

Fig. 3 is a diagram for explaining physical channels used in a 3GPP system and a typical signal transmission method using the same.

Fig. 4a and 4b illustrate SS/PBCH blocks for initial cell access in a 3GPP NR system.

Fig. 5a and 5b illustrate a procedure for transmitting control information and a control channel in a 3GPP NR system.

Fig. 6 illustrates a control resource set (CORESET) in which a physical downlink control channel (PUCCH) can be transmitted in a 3GPP NR system.

Fig. 7 illustrates a method for configuring a PDCCH search space in a 3GPP NR system.

Fig. 8 is a conceptual diagram illustrating carrier aggregation.

Fig. 9 is a diagram for explaining single carrier communication and multi-carrier communication.

Fig. 10 is a diagram showing an example in which a cross-carrier scheduling technique is applied.

Fig. 11 is a block diagram showing configurations of a UE and a base station according to an embodiment of the present invention.

Fig. 12 is a diagram illustrating scheduling of a Physical Downlink Shared Channel (PDSCH) according to an embodiment of the present invention.

Fig. 13 is a diagram illustrating scheduling of a Physical Uplink Control Channel (PUCCH) according to an embodiment of the present invention;

fig. 14 is a diagram illustrating scheduling of physical uplink shared channels and physical uplink control channels according to an embodiment of the present invention.

Fig. 15 is a diagram illustrating scheduling of a downlink shared channel according to a multi-slot scheduling according to an embodiment of the present invention;

Fig. 16 is a diagram illustrating uplink control channel transmission in one slot according to multi-slot scheduling according to an embodiment of the present invention;

Fig. 17 is a diagram illustrating uplink control channel transmission in two or more slots according to a multi-slot schedule according to an embodiment of the present invention;

Fig. 18 is a diagram illustrating downlink shared channel candidates corresponding to HARQ-ACKs when uplink control channels are transmitted on an nth slot according to an embodiment of the present invention.

Fig. 19 is a diagram illustrating HARQ-ACK occasions according to an embodiment of the present invention;

FIG. 20 is a diagram illustrating a time domain bundling window according to an embodiment of the present invention;

fig. 21 is a diagram illustrating a representative PDSCH according to a time domain bundling window according to an embodiment of the present invention;

fig. 22 is a diagram illustrating HARQ-ACK occasions according to a time domain bundling window according to an embodiment of the present invention; and

Fig. 23 is a flowchart illustrating an example of an operation of a terminal according to an embodiment of the present invention.

Detailed Description

The terms used in the specification adopt general terms currently widely used as much as possible by considering functions in the present invention, but may be changed according to the intention, habit, and appearance of new technology of those skilled in the art. In addition, in a specific case, there are terms arbitrarily selected by the applicant, and in this case, the meaning thereof will be described in the corresponding description section of the present invention. Therefore, it is intended that the terms used in the specification be construed not only based on the names of the terms but also based on the essential meanings of the terms and contents throughout the specification.

Throughout the specification and claims which follow, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element or "electrically connected" to the other element through a third element. In addition, unless explicitly described to the contrary, the word "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. Furthermore, in some exemplary embodiments, limitations such as "greater than or equal to" or "less than or equal to" based on a particular threshold, respectively, may be appropriately replaced with "greater than" or "less than," respectively.

The following techniques may be used in various wireless access systems: such as Code Division Multiple Access (CDMA), frequency Division Multiple Access (FDMA), time Division Multiple Access (TDMA), orthogonal Frequency Division Multiple Access (OFDMA), single carrier-FDMA (SC-FDMA), and the like. CDMA may be implemented by wireless technology such as Universal Terrestrial Radio Access (UTRA) or CDMA 2000. TDMA may be implemented by wireless technologies such as global system for mobile communications (GSM)/General Packet Radio Service (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA may be implemented by wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, evolved UTRA (E-UTRA), and the like. UTRA is part of Universal Mobile Telecommunications System (UMTS). The third generation partnership project (3 GPP) Long Term Evolution (LTE) is part of evolved UMTS (E-UMTS) using evolved UMTS terrestrial radio access (E-UTRA), and LTE-advanced (a) is an evolved version of 3GPP LTE. The 3GPP New Radio (NR) is a system designed separately from LTE/LTE-a and is a system for supporting enhanced mobile broadband (eMBB), ultra-reliable low-delay communication (URLLC), and large-scale machine type communication (mMTC) services as a requirement of IMT-2020. For clarity of description, the 3GPP NR is mainly described, but the technical ideas of the present invention are not limited thereto.

Unless otherwise specified herein, a base station may include a next generation node B (gNB) defined in a 3GPP NR. Further, unless specified otherwise, the terminal may include a User Equipment (UE). Hereinafter, to aid in understanding the description, each content is separately described by an embodiment, but each embodiment may be used in combination with each other. In this specification, the configuration of the UE may indicate the configuration by the base station. In more detail, the base station may configure values of parameters used in operation of the UE or the wireless communication system by transmitting channels or signals to the UE.

Referring to fig. 1, a radio frame (or radio frame) used in the 3gpp NR system may have a length of 10ms (Δf _maxN_f/100)*T_c). Further, the radio frame includes 10 Subframes (SFs) of equal size. Here ,Δf_max＝480*10³Hz,N_f＝4096,T_c＝1/(Δf_ref*N_f,ref),Δf_ref＝15*10³Hz, and N _f,ref =2048. Numbers from 0 to 9 may be allocated to 10 subframes within one radio frame, respectively. Each subframe is 1ms in length and may include one or more slots according to a subcarrier spacing. More specifically, in the 3GPP NR system, a subcarrier spacing that can be used is 15×2 ^μ kHz, and μ can have values of μ=0, 1, 2, 3, 4 as subcarrier spacing configurations. That is, 15kHz, 30kHz, 60kHz, 120kHz, and 240kHz may be used for subcarrier spacing. One subframe of length 1ms may include 2 ^μ slots. In this case, the length of each slot is 2 ^-μ ms. Numbers from 0 to 2 ^μ -1 may be allocated to 2 ^μ slots within one subframe, respectively. In addition, numbers from 0 to 10 x2 ^μ -1 may be allocated to slots within one radio frame, respectively. The time resources may be distinguished by at least one of a radio frame number (also referred to as a radio frame index), a subframe number (also referred to as a subframe index), and a slot number (or slot index).

Fig. 2 illustrates an example of a Downlink (DL)/Uplink (UL) slot structure in a wireless communication system. In particular, fig. 2 shows the structure of a resource grid of a 3GPP NR system.

There is one resource grid per antenna port. Referring to fig. 2, a slot includes a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain and a plurality of Resource Blocks (RBs) in a frequency domain. One OFDM symbol also refers to one symbol interval. OFDM symbols may be abbreviated as symbols unless otherwise specified. One RB includes 12 consecutive subcarriers in the frequency domain. Referring to fig. 2, a signal transmitted from each slot may be represented by a resource grid including N ^size,μ _grid,x*N^RB _sc subcarriers and N ^slot _symb OFDM symbols. Here, x=dl when the signal is a DL signal, and x=ul when the signal is an UL signal. N ^size,μ _grid,x denotes the number of Resource Blocks (RBs) according to the subcarrier spacing component μ (x is DL or UL), and N ^slot _symb denotes the number of OFDM symbols in a slot. N ^RB _sc is the number of subcarriers constituting one RB and N ^RB _sc =12. The OFDM symbol may be referred to as a cyclic shift OFDM (CP-OFDM) symbol or a discrete fourier transform spread OFDM (DFT-s-OFDM) symbol according to a multiple access scheme.

The number of OFDM symbols included in one slot may vary according to the length of a Cyclic Prefix (CP). For example, in the case of a normal CP, one slot includes 14 OFDM symbols, but in the case of an extended CP, one slot may include 12 OFDM symbols. In a particular embodiment, extended CP can only be used at 60kHz subcarrier spacing. In fig. 2, one slot is configured with 14 OFDM symbols as an example for convenience of description, but embodiments of the present invention can be applied to slots having different numbers of OFDM symbols in a similar manner. Referring to fig. 2, each OFDM symbol includes N ^size,μ _grid,x*N^RB _sc subcarriers in the frequency domain. The types of subcarriers may be divided into data subcarriers for data transmission, reference signal subcarriers for transmission of reference signals, and guard bands. The carrier frequency is also referred to as the center frequency (fc).

One RB may be defined by N ^RB _sc (e.g., 12) consecutive subcarriers in the frequency domain. For reference, a resource configured with one OFDM symbol and one subcarrier may be referred to as a Resource Element (RE) or tone. Thus, one RB can be configured with N ^slot _symb*N^RB _sc resource elements. Each resource element in the resource grid can be uniquely defined by a pair of indices (k, l) in one slot. k may be an index assigned from 0 to N ^size,μ _grid,x*N^RB _sc -1 in the frequency domain, and l may be an index assigned from 0 to N ^slot _symb -1 in the time domain.

For the UE to receive signals from or transmit signals to the base station, the time/frequency of the UE may be synchronized with the time/frequency of the base station. This is because when the base station and the UE are synchronized, the UE can determine time and frequency parameters necessary to demodulate the DL signal at the correct time and transmit the UL signal.

Each symbol of a radio frame used in Time Division Duplex (TDD) or unpaired spectrum may be configured with at least one of a DL symbol, an UL symbol, and a flexible symbol. A radio frame used as a DL carrier in Frequency Division Duplex (FDD) or paired spectrum may be configured with DL symbols or flexible symbols, and a radio frame used as an UL carrier may be configured with UL symbols or flexible symbols. In DL symbols, DL transmission is possible, but UL transmission is not possible. In UL symbols, UL transmission is possible, but DL transmission is not possible. The flexible symbols may be determined to be used as DL or UL according to the signal.

Information about the type of each symbol, i.e., information representing any one of DL symbols, UL symbols, and flexible symbols, may be configured with a cell-specific or common Radio Resource Control (RRC) signal. Furthermore, information about the type of each symbol may be additionally configured with UE-specific or dedicated RRC signals. The base station informs i) a period of a cell-specific slot configuration, ii) a number of slots having only DL symbols from a beginning of the period of the cell-specific slot configuration, iii) a number of DL symbols from a first symbol of a slot immediately after the slot having only DL symbols, iv) a number of slots having only UL symbols from an end of the period of the cell-specific slot configuration, and v) a number of UL symbols from a last symbol of the slot immediately before the slot having only UL symbols, by using a cell-specific RRC signal. Here, the symbol not configured with any one of the UL symbol and the DL symbol is a flexible symbol.

When the information on the symbol type is configured with a UE-specific RRC signal, the base station can signal whether the flexible symbol is a DL symbol or an UL symbol with a cell-specific RRC signal. In this case, the UE-specific RRC signal cannot change the DL symbol or UL symbol configured with the cell-specific RRC signal to another symbol type. The UE-specific RRC signal may signal the number of DL symbols among N ^slot _symb symbols of the corresponding slot and the number of UL symbols among N ^slot _symb symbols of the corresponding slot for each slot. In this case, DL symbols of the slot may be sequentially configured with first to i-th symbols of the slot. Further, the UL symbol of the slot may be successively configured with the j-th symbol through the last symbol of the slot (where i < j). In a slot, a symbol that is not configured with any one of UL symbols and DL symbols is a flexible symbol.

The type of symbol configured with the above RRC signal may be referred to as a semi-static DL/UL configuration. In a semi-static DL/UL configuration previously configured with RRC signals, flexible symbols may be indicated as DL symbols, UL symbol indications, or flexible symbols by dynamic Slot Format Information (SFI) transmitted on a Physical DL Control Channel (PDCCH). In this case, the DL symbol or UL symbol configured with the RRC signal is not changed to another symbol type. Table 1 illustrates the dynamic SFI that the base station can indicate to the UE.

TABLE 1

In table 1, D represents a DL symbol, U represents an UL symbol, and X represents a flexible symbol. As shown in table 1, a maximum of two DL/UL switches in one slot may be allowed.

Fig. 3 is a diagram for explaining physical channels used in a 3GPP system (e.g., NR) and a typical signal transmission method using the physical channels.

If the power of the UE is turned on or the UE camps on a new cell, the UE performs an initial cell search (S101). Specifically, the UE may synchronize with the BS in the initial cell search. To this end, the UE may receive a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell index. Thereafter, the UE can receive a physical broadcast channel from the base station and obtain broadcast information in the cell.

After the initial cell search is completed, the UE receives a Physical Downlink Shared Channel (PDSCH) according to a Physical Downlink Control Channel (PDCCH) and information in the PDCCH, so that the UE can obtain more specific system information than the system information obtained through the initial cell search (S102). Herein, the system information received by the UE is cell common system information for the UE to normally operate in a physical layer in Radio Resource Control (RRC) and is referred to as remaining system information, or as System Information Block (SIB) 1.

In case that the UE initially accesses the base station or there is no radio resource for signal transmission (the UE is in rrc_idle mode), the terminal may perform a random access procedure for the base station (operations S103 to S106). First, the UE may transmit a preamble through a Physical Random Access Channel (PRACH) (operation S103), and receive a Random Access Response (RAR) message for the preamble from the base station through a PDCCH and a PDSCH corresponding thereto (operation S104). The preamble in operations S103 and S104 may be described as message 1 (Msg 1), and the random access response may be described as a response message or message 2 (Msg 2). When a valid random access response is received by the UE, the UE may transmit data including an identifier of the UE to the base station through a Physical Uplink Shared Channel (PUSCH) indicated in an uplink grant transmitted from the base station through the PDCCH or PDSCH (operation S105). The data including the identifier of the UE and the PUSCH including the data in operation S105 may be described as message 3 (Msg 3). In addition, PUSCH including data may be described as message 3PUSCH (Msg 3 PUSCH). Next, the UE waits to receive the PDCCH as an indication of the base station to resolve the collision. When the UE successfully receives the PDCCH through the identifier of the UE and receives the PDSCH corresponding thereto (operation S106), the random access procedure is terminated. The PDCCH and PDSCH in operation S106 may be described as message 4 (Msg 4). The UE may obtain UE-specific system information on the RRC layer required for the UE to operate correctly on the physical layer during the random access procedure. When the UE acquires UE-specific system information from the RRC layer, the UE enters an rrc_connected mode.

The RRC layer is used to generate or manage messages for controlling the connection between the UE and the Radio Access Network (RAN). In more detail, the base station and the UE may perform cell system information required to broadcast each UE in a cell, manage mobility and handover, measurement reports of the UE, and storage management including UE capability management and device management in the RRC layer. In general, the RRC signal is not changed and maintains a considerably long interval because the period of update of a signal delivered in the RRC layer is longer than a Transmission Time Interval (TTI) in the physical layer.

After the above procedure, the UE receives a PDCCH/PDSCH (S107) and transmits a Physical Uplink Shared Channel (PUSCH)/Physical Uplink Control Channel (PUCCH) (S108) as a general UL/DL signal transmission procedure. In particular, the UE may receive Downlink Control Information (DCI) through the PDCCH. The DCI may include control information such as resource allocation information for the UE. In addition, the format of DCI may vary according to the intended use. Uplink Control Information (UCI) transmitted by a UE to a base station through UL includes DL/UL ACK/NACK signals, channel Quality Indicators (CQIs), precoding Matrix Indexes (PMIs), rank Indicators (RI), and the like. Here, CQI, PMI, and RI may be included in Channel State Information (CSI). In the 3GPP NR system, the UE can transmit control information such as the HARQ-ACK and CSI described above through the PUSCH and/or the PUCCH.

When power is turned on or a new cell is desired to be accessed, the UE may acquire time and frequency synchronization with the cell and perform an initial cell search procedure. The UE may detect the physical cell identity N ^cell _ID of the cell during the cell search procedure. To this end, the UE may receive synchronization signals, e.g., a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS), from the base station and synchronize with the base station. In this case, the UE can obtain information such as a cell Identification (ID).

Referring to fig. 4 (a), the Synchronization Signal (SS) will be described in more detail. The synchronization signals can be classified into PSS and SSS. The PSS may be used to obtain time domain synchronization and/or frequency domain synchronization, such as OFDM symbol synchronization and slot synchronization. SSS can be used to obtain frame synchronization and cell group ID. Referring to fig. 4 (a) and table 2, the ss/PBCH block can be configured with 20 RBs (=240 subcarriers) in succession on the frequency axis, and can be configured with 4 OFDM symbols in succession on the time axis. In this case, in the SS/PBCH block, PSS is transmitted in the first OFDM symbol and SSs is transmitted in the third OFDM symbol through 56 th to 182 th subcarriers. Here, the lowest subcarrier index of the SS/PBCH block is numbered from 0. In the first OFDM symbol in which the PSS is transmitted, the base station transmits no signal through the remaining subcarriers, i.e., the 0 th to 55 th subcarriers and the 183 th to 239 th subcarriers. Further, in the third OFDM symbol in which SSS is transmitted, the base station does not transmit signals through 48 th to 55 th subcarriers and 183 th to 191 th subcarriers. The base station transmits a Physical Broadcast Channel (PBCH) through the remaining REs in the SS/PBCH block except for the above signals.

TABLE 2

The SS allows a total of 1008 unique physical layer cell IDs to be grouped into 336 physical layer cell identifier groups by a combination of three PSS and SSs, each group comprising three unique identifiers, in particular such that each physical layer cell ID will be only part of one physical layer cell identifier group. Thus, the physical layer cell ID N ^cell _ID＝3N⁽¹⁾ _ID+N⁽²⁾ _ID can be uniquely defined by an index N ⁽¹⁾ _ID indicating a physical layer cell identifier group ranging from 0 to 335 and an index N indicating a physical layer identifier in the physical layer cell identifier group ranging from 0 to 2 (²)_ID. The UE can detect PSS and identify one of three unique physical layer identifiers.

d_PSS(n)＝1-2x(m)

0≤n<127

Here, x (i+7) = (x (i+4) +x (i)) mod2 and is given as

[x(6) x(5) x(4) x(3) x(2) x(1) x(0)]＝[1 1 1 0 1 1 0]

In addition, the sequence d _SSS (n) of SSS is as follows.

d_SSS(n)＝[1-2x₀((n+m₀)mod127)][1-2x₁((n+m₁)mod127)]

0≤n<127

Here the number of the elements is the number,And is given as

[x₀(6) x₀(5) x₀(4) x₀(3) x₀(2) x₀(1) x₀(0)]＝[0 0 0 0 0 0 1]

[x₁(6) x₁(5) x₁(4) x(3) x₁(2) x₁(1) x₁(0)]＝[0 0 0 0 0 0 1]

A radio frame having a length of 10ms may be divided into two half frames having a length of 5 ms. Referring to fig. 4 (b), a slot in which an SS/PBCH block is transmitted in each field will be described. The time slot in which the SS/PBCH block is transmitted may be any of cases A, B, C, D and E. In case a, the subcarrier spacing is 15kHz and the starting point in time of the SS/PBCH block is the (2, 8 +14 x n) th symbol. In this case, n=0 or 1 at a carrier frequency of 3GHz or less. Further, at carrier frequencies above 3GHz and below 6GHz, n=0, 1,2, 3 may be possible. In case B, the subcarrier spacing is 30kHz and the starting point in time of the SS/PBCH block is {4,8,16,20} +28 x n. In this case, n=0 at a carrier frequency of 3GHz or less. Further, n=0, 1 may be possible at carrier frequencies above 3GHz and below 6 GHz. In case C, the subcarrier spacing is 30kHz and the starting point in time of the SS/PBCH block is the (2, 8 +14 x n) th symbol. In this case, n=0 or 1 at a carrier frequency of 3GHz or less. Further, at carrier frequencies above 3GHz and below 6GHz, n=0, 1,2, 3 may be possible. In case D, the subcarrier spacing is 120kHz and the starting point in time of the SS/PBCH block is the ({ 4,8,16,20} +28 x n) th symbol. In this case, n=0, 1,2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18 at a carrier frequency of 6GHz or higher. In case E, the subcarrier spacing is 240kHz and the starting point in time of the SS/PBCH block is the ({ 8,12,16,20,32,36,40,44} +56 x n) th symbol. In this case, n=0, 1,2, 3, 5, 6, 7, 8 at a carrier frequency of 6GHz or higher.

Fig. 5 illustrates a procedure of transmitting control information and a control channel in a 3GPP NR system. Referring to fig. 5 (a), the base station may add a Cyclic Redundancy Check (CRC) masked (e.g., exclusive or operation) with a Radio Network Temporary Identifier (RNTI) to control information (e.g., downlink Control Information (DCI)) (S202). The base station may scramble the CRC with an RNTI value determined according to the purpose/destination of each control information. The common RNTI used by the one or more UEs can include at least one of a system information RNTI (SI-RNTI), a paging RNTI (P-RNTI), a random access RNTI (RA-RNTI), and a transmit power control RNTI (TPC-RNTI). Further, the UE-specific RNTI may include at least one of a cell temporary RNTI (C-RNTI) and a CS-RNTI. Thereafter, the base station may perform rate matching according to the amount of resources for PDCCH transmission (S206) after performing channel coding (e.g., polarity coding) (S204). Thereafter, the base station may multiplex DCI based on a PDCCH structure based on Control Channel Elements (CCEs) (S208). Further, the base station may apply additional procedures such as scrambling, modulation (e.g., QPSK), interleaving, etc. to the multiplexed DCI (S210), and then map the DCI to the resources to be transmitted. A CCE is a basic resource element for PDCCH, and one CCE may include a plurality of (e.g., six) Resource Element Groups (REGs). One REG may be configured with multiple (e.g., 12) REs. The number of CCEs for one PDCCH may be defined as an aggregation level. In a 3GPP NR system, an aggregation level of 1, 2,4, 8, or 16 can be used. Fig. 5B is a diagram related to multiplexing of CCE aggregation levels and PDCCHs, and illustrates types of CCE aggregation levels for one PDCCH and CCEs transmitted in a control region according thereto.

CORESET are time-frequency resources in which a PDCCH (i.e., control signals for the UE) is transmitted. In addition, a search space to be described later may be mapped to one CORESET. Thus, the UE may monitor the time-frequency domain designated CORESET instead of monitoring all frequency bands for PDCCH reception and decode the PDCCH mapped to CORESET. The base station may configure the UE with one or more CORESET for each cell. CORESET may be configured with up to three consecutive symbols on the time axis. Further, CORESET may be arranged in units of six consecutive PRBs on the frequency axis. In the embodiment of fig. 6, CORESET #1 is configured with contiguous PRBs, while CORESET #2 and CORESET #3 are configured with non-contiguous PRBs. CORESET can be located in any symbol in the slot. For example, in the embodiment of fig. 6, CORESET #1 starts with the first symbol of the slot, CORESET #2 starts with the fifth symbol of the slot, and CORESET #9 starts with the ninth symbol of the slot.

Fig. 7 illustrates a method for setting a PDCCH search space in a 3GPP NR system.

For transmitting the PDCCH to the UE, each CORESET may have at least one search space. In an embodiment of the present invention, the search space is a set of all time-frequency resources (hereinafter PDCCH candidates) that can be used to transmit the PDCCH of the UE. The search space may include a common search space that requires UEs of the 3GPP NR to search together and a UE-specific search space or UE-specific search space that requires a specific UE to search. In the common search space, UEs may monitor PDCCHs set such that all UEs in a cell belonging to the same base station search in common. Furthermore, a UE-specific search space may be set for each UE such that the UE monitors PDCCHs allocated to each UE at search space positions different according to the UE. In the case of UE-specific search spaces, the search spaces between UEs may be partially overlapped and allocated due to a limited control region in which PDCCHs may be allocated. Monitoring the PDCCH includes blind decoding the PDCCH candidates in the search space. When blind decoding is successful, it may be expressed as (successfully) detecting/receiving a PDCCH, and when blind decoding is failed, it may be expressed as not detecting/not receiving or not successfully detecting/receiving a PDCCH.

For convenience of explanation, a PDCCH scrambled with a Group Common (GC) RNTI previously known to one or more UEs in order to transmit DL control information to the one or more UEs is referred to as a Group Common (GC) PDCCH or a common PDCCH. In addition, a PDCCH scrambled with an RNTI of a specific terminal that the specific UE already knows in order to transmit UL scheduling information or DL scheduling information to the specific UE is referred to as a PDCCH of the specific UE. The common PDCCH may be included in the common search space, and the UE-specific PDCCH may be included in the common search space or the UE-specific PDCCH.

The base station may signal information about resource allocation of a Paging Channel (PCH) and a downlink shared channel (DL-SCH) as transport channels (i.e., DL grant) or information about resource allocation of an uplink shared channel (UL-SCH) and a hybrid automatic repeat request (HARQ) (i.e., UL grant) to each UE or UE group through the PDCCH. The base station may transmit the PCH transport block and the DL-SCH transport block through the PDSCH. The base station may transmit data excluding specific control information or specific service data through the PDSCH. In addition, the UE may receive data excluding specific control information or specific service data through the PDSCH.

The base station may include information on to which UE(s) PDSCH data is transmitted and how the PDSCH data is to be received and decoded by the corresponding UE in the PDCCH, and transmit the PDCCH. For example, assume that DCI transmitted on a specific PDCCH is CRC-masked with RNTI "a" and the DCI indicates that PDSCH is allocated to radio resource "B" (e.g., frequency location) and indicates transport format information "C" (e.g., transport block size, modulation scheme, coding information, etc.). The UE monitors the PDCCH using RNTI information possessed by the UE. In this case, if there is a UE performing blind decoding of the PDCCH using the "a" RNTI, the UE receives the PDCCH and receives PDSCH indicated by "B" and "C" through information of the received PDCCH.

Table 3 shows an embodiment of a Physical Uplink Control Channel (PUCCH) used in a wireless communication system.

TABLE 3

PUCCH format	Length of OFDM symbol	Number of bits
			0	1-2	≤2
1	4-14	≤2
			2	1-2	>2
3	4-14	>2
			4	4-14	>2

The PUCCH may be used to transmit the following UL Control Information (UCI).

Scheduling Request (SR): information for requesting UL-SCH resources.

HARQ-ACK: a response to PDCCH (indicating DL SPS release) and/or a response to DL Transport Block (TB) on PDSCH. The HARQ-ACK indicates whether information transmitted on the PDCCH or PDSCH is received. The HARQ-ACK response includes a positive ACK (abbreviated ACK), a negative ACK (hereinafter NACK), discontinuous Transmission (DTX), or NACK/DTX. Here, the term HARQ-ACK is used in combination with HARQ-ACK/NACK and ACK/NACK. Generally, an ACK may be represented by a bit value of 1, while a NACK may be represented by a bit value of 0.

Channel State Information (CSI): feedback information about DL channels. The UE generates it based on CSI-Reference Signals (RSs) transmitted by the base station. Multiple Input Multiple Output (MIMO) -related feedback information includes a Rank Indicator (RI) and a Precoding Matrix Indicator (PMI). The CSI can be divided into CSI part 1 and CSI part 2 according to information indicated by the CSI.

In the 3GPP NR system, five PUCCH formats may be used to support various service scenarios, various channel environments, and frame structures.

PUCCH format 0 is a format capable of delivering 1-bit or 2-bit HARQ-ACK information or SR. PUCCH format 0 can be transmitted through one or two OFDM symbols on the time axis and one PRB on the frequency axis. When PUCCH format 0 is transmitted in two OFDM symbols, the same sequence on the two symbols may be transmitted through different RBs. In this case, the sequence may be a sequence cyclic-shifted (CS) from a base sequence used in PUCCH format 0. Through this, the UE can obtain a frequency diversity gain. In more detail, the UE may determine a Cyclic Shift (CS) value M _cs according to M _bit -bit UCI (M _bit =1 or 2). In addition, the base sequence of length 12 may be transmitted by mapping a cyclic shift sequence based on a predetermined CS value m _cs to 12 REs of one OFDM symbol and one RB. When the number of cyclic shifts available to the UE is 12 and M _bit =1, 1-bit UCI 0 and 1 may be mapped to two cyclic shift sequences with a difference of 6 in cyclic shift value, respectively. In addition, when M _bit =2, 2 bits UCI 00, 01, 11, and 10 may be mapped to four cyclic shift sequences with a difference of 3 in cyclic shift value, respectively.

PUCCH format 1 may deliver 1-bit or 2-bit HARQ-ACK information or SRs. PUCCH format 1 may be transmitted through consecutive OFDM symbols on the time axis and one PRB on the frequency axis. Here, the number of OFDM symbols occupied by PUCCH format 1 may be one of 4 to 14. More specifically, UCI with M _bit =1 may be BPSK modulated. The UE may modulate UCI with M _bit =2 using Quadrature Phase Shift Keying (QPSK). The signal is obtained by multiplying the modulated complex-valued symbol d (0) by a sequence of length 12. In this case, the sequence may be a base sequence for PUCCH format 0. The UE expands the even-numbered OFDM symbols to which PUCCH format 1 is allocated by a time axis Orthogonal Cover Code (OCC) to transmit the obtained signal. PUCCH format 1 determines the maximum number of different UEs multiplexed in one RB according to the length of OCC to be used. Demodulation reference signals (DMRS) may be extended with OCC and mapped to odd-numbered OFDM symbols of PUCCH format 1.

PUCCH format 2 may deliver UCI of more than 2 bits. PUCCH format 2 may be transmitted through one or two OFDM symbols on the time axis and one or more RBs on the frequency axis. When PUCCH format 2 is transmitted in two OFDM symbols, sequences transmitted in different RBs through the two OFDM symbols may be identical to each other. Here, the sequence may be a plurality of modulated complex-valued symbols d (0), -d (M _symbol -1). Here, M _symbol may be M _bit/2. Through this, the UE can obtain a frequency diversity gain. More specifically, M _bit bits UCI (M _bit > 2) are bit-level scrambled, QPSK modulated, and mapped to RBs of one or two OFDM symbols. Here, the number of RBs may be one of 1 to 16.

PUCCH format 3 or PUCCH format 4 may deliver UCI of more than 2 bits. PUCCH format 3 or PUCCH format 4 may be transmitted through consecutive OFDM symbols on the time axis and one PRB on the frequency axis. The number of OFDM symbols occupied by PUCCH format 3 or PUCCH format 4 may be one of 4 to 14. Specifically, the UE modulates M _bit bits UCI (M _bit > 2) with pi/2-Binary Phase Shift Keying (BPSK) or QPSK to generate complex-valued symbols d (0) to d (M _symb -1). Here, when pi/2-BPSK is used, M _symb＝M_bit, and when QPSK is used, M _symb＝M_bit/2. The UE may not apply block unit extension to PUCCH format 3. However, the UE may apply block unit spreading to one RB (i.e., 12 subcarriers) using PreDFT-OCC of length 12, so that PUCCH format 4 may have two or four multiplexing capabilities. The UE performs transmit precoding (or DFT precoding) on the spread signal and maps it to each RE to transmit the spread signal.

In this case, the number of RBs occupied by PUCCH format 2, PUCCH format 3 or PUCCH format 4 may be determined according to the length of UCI transmitted by the UE and the maximum coding rate. When the UE uses PUCCH format 2, the UE may transmit HARQ-ACK information and CSI information together through the PUCCH. When the number of RBs that the UE can transmit is greater than the maximum number of RBs that the PUCCH format 2, PUCCH format 3, or PUCCH format 4 can use, the UE can transmit only the remaining UCI information without transmitting some UCI information according to the priority of the UCI information.

PUCCH format 1, PUCCH format 3, or PUCCH format 4 may be configured by an RRC signal to indicate frequency hopping in a slot. When frequency hopping is configured, an index of RBs to be frequency hopped can be configured with an RRC signal. When PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted through N OFDM symbols of the time axis, the first hop may have floor (N/2) OFDM symbols and the second hop may have ceiling (N/2) OFDM symbols.

PUCCH format 1, PUCCH format 3, or PUCCH format 4 may be configured to be repeatedly transmitted in a plurality of slots. In this case, the number K of slots in which the PUCCH is repeatedly transmitted may be configured by an RRC signal. The repeatedly transmitted PUCCH must start with an OFDM symbol at a constant position in each slot and have a constant length. When one OFDM symbol among OFDM symbols of a slot in which the UE should transmit the PUCCH is indicated as a DL symbol through an RRC signal, the UE may not transmit the PUCCH in the corresponding slot and delay transmission of the PUCCH to the next slot to transmit the PUCCH.

Meanwhile, in the 3GPP NR system, the UE may perform transmission/reception using a bandwidth equal to or less than that of a carrier (or cell). To this end, the UE may receive a bandwidth portion (BWP) of a continuous bandwidth configured with some carrier bandwidths. A UE operating according to TDD or operating in unpaired spectrum may receive up to four DL/UL BWP pairs in one carrier (or cell). In addition, the UE may activate one DL/UL BWP pair. A UE operating according to FDD or operating in the paired spectrum is able to receive up to four DL BWP on DL carriers (or cells) and up to four UL BWP on UL carriers (or cells). The UE may activate one DL BWP and one UL BWP for each carrier (or cell). The UE may not perform reception or transmission in time-frequency resources other than the activated BWP. The activated BWP may be referred to as an active BWP.

The base station may indicate an activated BWP among BWP configured by the UE through Downlink Control Information (DCI). BWP indicated by DCI is activated and BWP of other configuration is deactivated. In a carrier (or cell) operating in TDD, a base station may include a Bandwidth Part Indicator (BPI) indicating BWP to be activated in DCI for scheduling PDSCH or PUSCH to change DL/UL BWP pairs of a UE. The UE may receive DCI for scheduling PDSCH or PUSCH and may identify DL/UL BWP pairs activated based on BPI. For DL carriers (or cells) operating in FDD, the base station may include BPI indicating BWP to be activated in DCI for scheduling PDSCH to change DL BWP of the UE. For UL carriers (or cells) operating in FDD, the base station may include BPI indicating BWP to be activated in DCI for scheduling PUSCH in order to change UL BWP of the UE.

Fig. 8 is a conceptual diagram illustrating carrier aggregation.

Carrier aggregation is a method in which a UE uses a plurality of frequency blocks or (in a logical sense) cells configured with UL resources (or component carriers) and/or DL resources (or component carriers) as one large logical band in order for a wireless communication system to use a wider frequency band. One component carrier may also be referred to as a term called primary cell (PCell) or secondary cell (SCell) or primary SCell (PScell). Hereinafter, however, for convenience of description, the term "component carrier" is used.

Referring to fig. 8, as an example of the 3GPP NR system, the entire system band may include at most 16 component carriers, and each component carrier may have a bandwidth of at most 400 MHz. The component carriers may include one or more physically contiguous subcarriers. Although each component carrier is shown in fig. 8 as having the same bandwidth, this is merely an example, and each component carrier may have a different bandwidth. In addition, although each component carrier is shown as being adjacent to each other on the frequency axis, the drawing is logically shown, and each component carrier may be physically adjacent to each other or may be spaced apart.

A different center frequency may be used for each component carrier. In addition, one common center frequency may be used in physically adjacent component carriers. Assuming that all component carriers are physically adjacent in the embodiment of fig. 8, the center frequency a may be used in all component carriers. In addition, the center frequency a and the center frequency B can be used in each component carrier, assuming that the respective component carriers are not physically adjacent to each other.

When the total system band is extended by carrier aggregation, a band for communication with each UE can be defined in units of component carriers. UE a may use 100MHz as a total system band and perform communication using all five component carriers. UE B ₁～B₅ can perform communication using only a 20MHz bandwidth and using one component carrier. UE C ₁ and C ₂ may perform communication using a 40MHz bandwidth and using two component carriers, respectively. The two component carriers may or may not be logically/physically contiguous. UE C ₁ represents a case where two non-adjacent component carriers are used, and UE C ₂ represents a case where two adjacent component carriers are used.

Fig. 9 is a diagram for explaining single carrier communication and multi-carrier communication. In particular, fig. 9 (a) shows a single carrier subframe structure and fig. 9 (b) shows a multi-carrier subframe structure.

Referring to fig. 9 (a), in the FDD mode, a general wireless communication system may perform data transmission or reception through one DL frequency band and one UL frequency band corresponding thereto. In another particular embodiment, in TDD mode, the wireless communication system may divide a radio frame into UL time units and DL time units in the time domain and perform data transmission or reception through the UL/DL time units. Referring to fig. 9 (b), three 20MHz Component Carriers (CCs) can be aggregated into each of UL and DL so that a bandwidth of 60MHz can be supported. Each CC may or may not be adjacent to each other in the frequency domain. Fig. 9 (b) shows a case where the bandwidth of the UL CC and the bandwidth of the DL CC are the same and symmetrical, but the bandwidth of each CC can be independently determined. Furthermore, asymmetric carrier aggregation with different numbers of UL CCs and DL CCs is possible. DL/UL CCs allocated/configured to a specific UE through RRC may be referred to as serving DL/UL CCs of the specific UE.

The base station may perform communication with the UE by activating some or all of the serving CCs of the UE or disabling some CCs. The base station can change CCs to be activated/deactivated and change the number of CCs to be activated/deactivated. If the base station allocates CCs available to the UE as cell-specific or UE-specific, at least one of the allocated CCs will not be deactivated unless the CC allocation for the UE is completely reconfigured or the UE is switched. One CC that is not deactivated by the UE is referred to as a primary CC (PCC) or primary cell (PCell), and a CC that the base station can freely activate/deactivate is referred to as a secondary CC (SCC) or secondary cell (SCell).

Meanwhile, 3GPP NR manages radio resources using the concept of a cell. A cell is defined as a combination of DL resources and UL resources, i.e., a combination of DL CCs and UL CCs. A cell may be configured with DL resources alone or may be configured with a combination of DL and UL resources. When carrier aggregation is supported, a link between a carrier frequency of a DL resource (or DL CC) and a carrier frequency of a UL resource (or UL CC) may be indicated by system information. The carrier frequency refers to the center frequency of each cell or CC. The cell corresponding to the PCC is referred to as PCell, and the cell corresponding to the SCC is referred to as SCell. The carrier corresponding to the PCell in DL is DL PCC and the carrier corresponding to the PCell in UL is UL PCC. Similarly, the carrier in DL corresponding to SCell is DL SCC, and the carrier in UL corresponding to SCell is UL SCC. Depending on the UE capabilities, the serving cell may be configured with one PCell and zero or more scells. In the case of a UE in the rrc_connected state but not configured for carrier aggregation or not supporting carrier aggregation, only one serving cell is configured with only PCell.

As described above, the term "cell" used in carrier aggregation is distinguished from the term "cell" which refers to a certain geographical area where communication services are provided through one base station or one antenna group. That is, one component carrier may also be referred to as a scheduling cell, a scheduled cell, a primary cell (PCell), a secondary cell (SCell), or a primary SCell (PScell). However, in order to distinguish between a cell representing a certain geographical area and a carrier aggregated cell, in the present invention, the carrier aggregated cell is referred to as a CC, and the cell of the geographical area is referred to as a cell.

Fig. 10 is a diagram showing an example in which a cross-carrier scheduling technique is applied. When the cross-carrier scheduling is set, a control channel transmitted through the first CC may schedule a data channel transmitted through the first CC or the second CC using a Carrier Indicator Field (CIF). CIF is included in DCI. In other words, a scheduling cell is set, and DL grant/UL grant transmitted in the PDCCH region of the scheduling cell schedules PDSCH/PUSCH of the cell to be scheduled. That is, there is a search region for a plurality of component carriers in the PDCCH region of the scheduling cell. The PCell may basically be a scheduling cell, and a specific SCell may be designated as a scheduling cell by an upper layer.

In the embodiment of fig. 10, it is assumed that three DL CCs are combined. Here, it is assumed that DL component carrier #0 is DL PCC (or PCell), and DL component carrier #1 and DL component carrier #2 are DL SCCs (or scells). Further, it is assumed that DL PCC is set as PDCCH monitoring CC. When cross-carrier scheduling is not configured by UE-specific (or UE group-specific or cell-specific) higher layer signaling, CIF is disabled and each DL CC can transmit only PDCCH for scheduling its PDSCH without CIF according to NR PDCCH rules (non-cross-carrier scheduling, self-carrier scheduling). Meanwhile, if cross-carrier scheduling is configured through UE-specific (or UE group-specific or cell-specific) higher layer signaling, CIF is enabled, and a specific CC (e.g., DL PCC) may use CIF to transmit not only PDCCH for scheduling PDSCH of DL CC a but also PDCCH for scheduling PDSCH of another CC (cross-carrier scheduling). On the other hand, the PDCCH is not transmitted in another DL CC. Accordingly, the UE monitors a PDCCH including no CIF to receive a PDSCH from the carrier scheduling according to whether the UE is configured with the cross-carrier scheduling, or monitors a PDCCH including CIF to receive a PDSCH of the cross-carrier scheduling.

On the other hand, fig. 9 and 10 illustrate subframe structures of the 3GPP LTE-a system, and the same or similar configuration may be applied to the 3GPP NR system. However, in the 3GPP NR system, the subframes of fig. 9 and 10 may be replaced with slots.

Fig. 11 is a block diagram illustrating a configuration of a UE and a base station according to an embodiment of the present disclosure.

In embodiments of the present invention, a terminal may be implemented as various types of wireless communication devices or computing devices that ensure portability and mobility. A terminal may be referred to as a User Equipment (UE), a Station (STA), a Mobile Subscriber (MS), etc. In addition, in the embodiment of the present invention, the base station may control and manage a cell (e.g., a macro cell, a femto cell, or a pico cell) corresponding to a service area and perform functions such as signal broadcasting, channel assignment, channel monitoring, self diagnosis, and relay. A base station may be referred to as a next generation node B (gNB) or an Access Point (AP).

As shown, the terminal 100 according to an embodiment of the present invention may include a processor 110, a communication module 120, a memory 130, a user interface unit 140, and a display unit 150.

First, the processor 110 may execute various commands or programs and process data in the terminal 100. Further, the processor 110 may control the entire operation of each unit including the terminal 100, and control data transmission or reception between the units. The processor 110 may be configured to perform operations according to embodiments described in the present invention. For example, the processor 110 may receive slot configuration information, determine a configuration of slots based on the information, and perform communication according to the determined slot configuration.

Next, the communication module 120 may be an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. To this end, the communication module 120 may include a plurality of Network Interface Cards (NICs) of an internal or external type, such as cellular communication interface cards 121 and 122 and an unauthorized communication interface card 123. In the figures, the communication module 120 is illustrated as an integrated module. However, each of the network interface cards may be independently set according to a circuit configuration or use, unlike in the figures.

The cellular communication interface card 121 may transmit or receive a wireless signal to or from at least one of the base station 200, an external device, and a server by using a mobile communication network, and provide a cellular communication service using a first frequency band based on a command of the processor 110. According to an embodiment, the cellular communication interface card 121 may include at least one NIC module using a frequency band below 6 GHz. At least one NIC module of the cellular communication interface card 121 may independently perform cellular communication with at least one of the base station 200, the external device, and the server according to a cellular communication specification or protocol for a frequency band lower than 6GHz supported by the NIC module.

The cellular communication interface card 122 may transmit or receive a wireless signal to or from at least one of the base station 200, the external device, and the server by using the mobile communication network, and provide a cellular communication service using the second frequency band based on a command of the processor 110. According to an embodiment, the cellular communication interface card 122 may include at least one NIC module using a 6GHz or higher frequency band. At least one NIC module of the cellular communication interface card 122 may independently perform cellular communication with at least one of the base station 200, the external device, and the server according to cellular communication specifications or protocols for a 6GHz or higher band supported by the NIC module.

The unlicensed-band communication interface card 123 may transmit or receive wireless signals to or from at least one of the base station 200, the external device, and the server by using a third frequency band that is an unlicensed band, and provide communication services of the unlicensed band based on a command of the processor 110. The unlicensed communication interface card 123 may include at least one NIC module using an unlicensed band. For example, the unlicensed band may be a band equal to or higher than 2.4GHz, 5GHz, 6GHz, 7GHz, or 52.6 GHz. At least one NIC module of the unlicensed communication interface card 123 may perform wireless communication with at least one of the base station 200, the external device, and the server independently or in association according to unlicensed band communication specifications or protocols of frequency bands supported by the NIC module.

Next, the memory 130 stores a control program and various related data used in the terminal 100. The control program may include a predetermined program required for the terminal 100 to perform wireless communication with at least one of the base station 200, an external device, and a server.

Next, the user interface 140 includes various types of input/output devices provided in the terminal 100. That is, the user interface 140 may receive user input by using various input devices, and the processor 110 may control the terminal 100 based on the received user input. Further, the user interface 140 may perform output based on a command of the processor 110 by using various output devices.

Next, the display unit 150 outputs various images on the display screen. The display unit 150 may output various display objects such as contents executed by the processor 110 or a user interface based on control commands of the processor 110.

In addition, the base station 200 according to an embodiment of the present invention may include a processor 210, a communication module 220, and a memory 230.

First, the processor 210 may execute various commands or programs and process data in the base station 200. Further, the processor 210 may control the entire operation of each unit including the base station 200, and control data transmission or reception between the units. The processor 210 may be configured to perform operations according to embodiments described in the present invention. For example, the processor 210 may perform signaling of slot configuration information and perform communication according to the signaled slot configuration.

Next, the communication module 220 may be an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. To this end, the communication module 220 may include a plurality of network interface cards of an internal or external type, such as cellular communication interface cards 221 and 222 and an unauthorized communication interface card 223. In the figures, the communication module 220 is illustrated as an integrated module. However, each of the network interface cards may be independently set according to a circuit configuration or use, unlike in the figures.

The cellular communication interface card 221 may transmit or receive a wireless signal to or from at least one of the terminal 100, the external device, and the server by using the mobile communication network, and provide a cellular communication service using the first frequency band based on a command of the processor 210. According to an embodiment, the cellular communication interface card 221 may include at least one NIC module using a frequency band below 6 GHz. At least one NIC module of the cellular communication interface card 221 may independently perform cellular communication with at least one of the terminal 100, the external device, and the server according to a cellular communication specification or protocol of a frequency band lower than 6GHz supported by the NIC module.

The cellular communication interface card 222 may transmit or receive a wireless signal to or from at least one of the terminal 100, the external device, and the server by using the mobile communication network, and provide a cellular communication service using the second frequency band based on a command of the processor 210. According to an embodiment, the cellular communication interface card 222 may include at least one NIC module using a 6GHz or higher frequency band. At least one NIC module of the cellular communication interface card 222 may independently perform cellular communication with at least one of the terminal 100, the external device, and the server according to a cellular communication specification or protocol of a frequency band of 6GHz or higher supported by the NIC module.

The unlicensed band communication interface card 223 may transmit or receive wireless signals to or from at least one of the terminal 100, the external device, and the server by using a third frequency band that is an unlicensed band, and provide communication services of the unlicensed band based on a command of the processor 210. The unauthorized communications interface card 223 may include at least one NIC module that uses unauthorized bands. For example, the unlicensed band may be a frequency band equal to or higher than 2.4GHz, 5GHz, 6GHz, 7GHz, or 52.6 GHz. At least one NIC module of the unlicensed communication interface card 223 may perform wireless communication independently or in association with at least one of the terminal 100, the external device, and the server according to an unlicensed band communication specification or protocol of a frequency band supported by the NIC module.

The terminal 100 and the base station 200 shown in fig. 11 are expressed in a block diagram according to an embodiment of the present invention, and separate blocks are illustrated to logically distinguish between elements of the device. Thus, depending on the design of the device, the elements of the device may be mounted as a single chip or as multiple chips. In addition, part of the configuration of the terminal 100, for example, the user interface 140 and the display unit 150, may be optionally included in the terminal 100. In addition, the user interface 140 and the display unit 150 may be additionally included in the base station 200 as needed.

Hereinafter, a method of receiving a physical downlink control channel and a physical downlink shared channel by a terminal and a method of transmitting a physical uplink control channel and a physical uplink shared channel are described with reference to fig. 12 and 13.

The terminal may receive a physical downlink control channel transmitted from the base station and may configure information such as a control resource set (CORESET) or a search space for the terminal to receive the downlink control channel.

The control resource set includes information of a frequency region in which the physical downlink control channel needs to be received. More specifically, the information of the control resource set may include an index of PRBs or PRB sets that the terminal is required to receive the physical downlink control channel and the number of consecutive symbols. The number of consecutive symbols is one of 1,2 and 3.

The search space includes time information about a time required to receive the PRB set indicated by the control resource set. More specifically, the information of the search space may include information of at least one of a period (periodicity) and an offset. The period (periodicity) or offset may be indicated by a unit of time slot, sub-slot, symbol set, or time slot set. In addition, the information of the search space may include a CCE aggregation level received by the terminal, the number of PDCCHs monitored per CCE aggregation level, a search space type, or DCI format or RNTI information monitored.

The CCE aggregation level has at least one value of 1,2, 4, 8 and 16. The terminal may monitor the PDCCH on Control Channel Elements (CCEs) whose number is equal to the value of the CCE aggregation level.

The search space types may be a Common Search Space (CSS) and a terminal-specific search space (UE-specific search space). The common search space refers to a search space in which all terminals of a cell or a part of terminals of a cell commonly monitor a PDCCH. The terminal may monitor and receive PDCCH candidates broadcast to all terminals of the cell or some terminals of the cell in the search space (e.g., PDCCH is a PDCCH transmitting DCI with CRC scrambled by at least one RNTI of SI-RNTI、RA-RNTI、MsgB-RNTI、P-RNTI、TC-RNTI、INT-RNTI、SFI-RNTI、TPC-PUSCH-RNTI、TPC-PUCCH-RNTI、TPC-SRS-RNTI、CI-RNTI、C-RNTI、MCS-C-RNTI、CS-RNTI or PS-RNTI). The terminal may monitor and receive PDCCH candidates transmitted to the respective terminals in a terminal-specific search space (e.g., PDCCH is a PDCCH transmitting DCI with CRC scrambled by at least one RNTI of C-RNTI, MCS-C-RNTI, SP-CSI-RNTI, CS-RNTI, SL-CS-RNTI, or SL-L-CS-RNTI). In addition, the terminal may receive a PDCCH transmitting DCI indicating reception of a physical downlink shared channel, transmission of a physical uplink control channel, or transmission of a physical uplink shared channel in a common search space and a terminal-specific search space.

The DCI format monitored by a terminal scheduled by a base station to transmit a physical uplink shared channel and receive a physical downlink shared channel may be DCI format 0_0, 0_1, 0_2, 1_0, 1_1 or 1_2. In case of DCI formats 0_0, 0_1, 0_2, 1_0, 1_1, or 1_2, the RNTI information may include at least one RNTI among CS-RNTI, MCS-C-RNTI, and C-RNTI. The CS-RNTI may be used by the base station to schedule activation/release or retransmission of a semi-persistent (SPS) PDSCH or a Configured Grant (CG) PUSCH and may also be used by the terminal to receive it. The MCS-C-RNTI may be used by the base station to schedule PDSCH or PUSCH using a Modulation and Coding Scheme (MCS) with high reliability and may be used by the terminal to receive it. The C-RNTI may be used by the base station to schedule PDSCH or PUSCH and may be used by the terminal to receive it.

In addition, the DCI format that may be included in the PDCCH monitored by the terminal may additionally include at least the following.

DCI format 2_0 includes dynamic Slot Format Indicator (SFI) information indicating that the direction of a symbol of a slot is uplink, downlink or flexible symbols. The RNTI for DCI format 2_0 is an SFI-RNTI.

DCI format 2_1 includes a DL preemption indication (or an interrupt transmission indication) indicating that there is no downlink transmission from a base station to a terminal on PRBs and symbols. The RNTI for DCI format 2_1 is an INT-RNTI.

DCI format 2_4 represents an UL cancellation indication that instructs a terminal to cancel uplink transmission on PRBs and symbols. The RNTI for DCI format 2_4 is CI-RNTI.

The terminal may determine PDCCH candidates on which the PDCCH needs to be received through information of the configured control resource set and search space. The terminal may monitor the PDCCH candidates, check the CRC with the RNTI value, and then determine whether the correct PDCCH has been received. The RNTI values may include SFI-RNTI, INT-RNTI, and CI-RNTI values in addition to at least the C-RNTI, MCS-C-RNTI, and CS-RNTI.

If the terminal receives the correct PDCCH, the terminal may interpret Downlink Control Information (DCI) transmitted by the PDCCH based on the information of the control resource set and the search space and perform an operation indicated in the DCI. The DCI may include one of DCI formats 0_0, 0_1, and 0_2 that schedule a Physical Uplink Shared Channel (PUSCH). The DCI may include one of DCI formats 1_0, 1_1, and 1_2 that schedule a Physical Downlink Shared Channel (PDSCH). The DCI may include one of DCI formats 1_0, 1_1, and 1_2 that schedule a Physical Uplink Control Channel (PUCCH). For reference, the PUCCH may include a PUCCH transmitting HARQ-ACK. In addition, the DCI may include DCI formats 2_0, 2_1, or 2_4.

In the case where the terminal receives DCI format 1_0, 1_1 or 1_2 of scheduling Physical Downlink Shared Channel (PDSCH), the terminal is required to receive the downlink shared channel scheduled by the DCI format. For this, the terminal is required to interpret (determine) the slot of the scheduled physical downlink shared channel and the start index and length of the symbol in the slot through the DCI format. The Time Domain Resource Allocation (TDRA) field of DCI format 1_0, 1_1, or 1_2 may indicate a K0 value as timing information of a scheduling slot and a Start Length Indicator Value (SLIV) as an index and length of a start symbol in the slot. Here, the value of K0 may be a non-negative integer value. Here, SLIV may be a value obtained by jointly encoding a value of an index of a start symbol in a slot and a value of a length (L). In addition, SLIV may separately transmit the value of the index and the value of the length (L) of the start symbol in the slot. In case of the normal CP, S may have one value among 0, 1, …, 13, and L may have one value among natural numbers satisfying the condition that s+l is less than or equal to 14. S may have one value among 0, 1, …, 11 in the case of the extended CP, and L may have one value among natural numbers satisfying the condition that s+l is less than or equal to 12.

The terminal may determine a time slot on which to receive a Physical Downlink Shared Channel (PDSCH) based on the K0 value. More specifically, the terminal may determine a slot on which a physical downlink shared channel needs to be received based on a K0 value, an index of a slot in which the DCI is received, a subcarrier spacing (SCS) of a downlink BWP in which the DCI is received, or a subcarrier spacing of a downlink BWP in which a scheduled downlink shared channel is received.

For example, it is assumed that a downlink BWP in which DCI is received and a downlink BWP in which a scheduled Physical Downlink Shared Channel (PDSCH) is received have the same subcarrier spacing. Suppose that DCI has been received on downlink slot n. At this time, a downlink shared channel (PDSCH) needs to be received on the downlink slot n+k0.

For example, assume that a subcarrier spacing of downlink BWP receiving DCI is 15kHz x 2 mu_PDCCH, and a subcarrier spacing of downlink BWP receiving a scheduled Physical Downlink Shared Channel (PDSCH) is 15kHz x 2 mu_PDSCH. Suppose that DCI has been received on downlink slot n. The index of the downlink slot n is an index based on a subcarrier spacing of downlink BWP receiving DCI. In this case, it is necessary to receive the physical downlink shared channel on the slot floor (n 2 mu_pdsch/2 mu_pdcch) +k0. The index floor (n×2 μm_pdsch/2 μm_pdcch) +k0 of the downlink slot is an index based on the subcarrier spacing of the downlink BWP of the receiving physical downlink shared channel. In the above description, mu_pdcch or mu_pdsch may have a value of 0, 1, 2, or 3.

Referring to fig. 12, a PDSCH may be scheduled for a terminal through a specific format of DCI of a PDCCH.

Specifically, as shown in fig. 12, a terminal may receive a PDCCH scheduling a Physical Downlink Shared Channel (PDSCH) on a downlink slot n. Let K0 of DCI transmitted through PDCCH indicate 3. In addition, it is assumed that a subcarrier interval of DL BWP receiving PDCCH and a subcarrier interval of DL BWP scheduling PDSCH are the same. At this time, the terminal may determine to schedule PDSCH on downlink slot n+k0, i.e., slot n+3.

The terminal may determine a symbol required to receive a Physical Downlink Shared Channel (PDSCH) in a slot required to receive the downlink shared channel (PDSCH) based on a K0 value by using a length (L) and an index (S) of a start symbol in the slot. The symbols required to receive the Physical Downlink Shared Channel (PDSCH) correspond to symbols S through s+l-1 in the slot obtained based on the K0 value. For reference, the symbols S through S+L-1 are L consecutive symbols.

The base station may additionally configure downlink slot aggregation for the terminal. The downlink slot aggregation values may be 2, 4, 8. When downlink slot aggregation is configured, a terminal is required to receive a Physical Downlink Shared Channel (PDSCH) from consecutive slots corresponding to a slot aggregation value from a slot obtained based on a K0 value.

In case that the terminal has received DCI format 1_0, 1_1 or 1_2 of the scheduled physical uplink control channel, the terminal is required to transmit the scheduled uplink control channel. The physical uplink control channel may include HARQ-ACK information. The PDSCH-to-HARQ-feedback timing indicator field included in DCI format 1_0, 1_1, or 1_2 may indicate a K1 value, which is a value for information of a slot on which a scheduled uplink control channel needs to be transmitted. Here, the value of K1 may be a non-negative integer value. The K1 value of DCI format 1_0 may indicate one value among 0, 1, 2, 3, 4, 5, 6 and 7. The K1 value indicated in the DCI format 1_1 or 1_2 may be configured or set from a higher layer.

The HARQ-ACK information may be HARQ-ACK information regarding whether or not both types of channels have been successfully received. As a first type, if a Physical Downlink Shared Channel (PDSCH) is scheduled through DCI format 1_0, 1_1, or 1_2, HARQ-ACK information may be HARQ-ACK related to whether the Physical Downlink Shared Channel (PDSCH) has been successfully received. As a second type, if DCI format 1_0, 1_1, or 1_2 is DCI indicating release of a semi-persistent physical downlink shared channel (SPS PDSCH), HARQ-ACK information may be HARQ-ACK related to whether DCI format 1_0, 1_1, or 1_2 has been successfully received.

The terminal may determine a slot on which to transmit an uplink control channel including first type HARQ-ACK information as follows. The terminal may determine an uplink slot overlapping with a last symbol of a Physical Downlink Shared Channel (PDSCH) corresponding to the HARQ-ACK information. When the index of the uplink slot is m, the uplink slot in which the terminal transmits the physical uplink control channel including HARQ-ACK information may be m+k1. The index of the uplink slot is based on the value of the subcarrier spacing of the uplink BWP transmitting the uplink control channel.

For reference, when downlink slot aggregation is configured for a terminal, an end symbol indicates a last symbol of a Physical Downlink Shared Channel (PDSCH) scheduled in a last slot among slots receiving the PDSCH.

Fig. 13 is a diagram illustrating scheduling of a Physical Uplink Control Channel (PUCCH) according to an embodiment of the present invention.

Referring to fig. 13, a terminal may receive scheduling information for a PDSCH and transmission of a PUCCH through DCI of a PDCCH, and receive the PDSCH and transmit the PUCCH based on the received DCI.

Specifically, as shown in fig. 13, the terminal may receive a PDCCH scheduling a downlink shared channel (PDSCH) on a downlink slot n. The DCI transmitted from the PDCCH may include scheduling information for reception of the PDSCH and transmission of the PUCCH. For example, if the value of K0 included in DCI is "3", the value of K1 is "2", and the subcarrier spacing of DL BWP in which the PDCCH is received, the subcarrier spacing of DL BW in which the PDSCH is scheduled, and the subcarrier spacing of UL BWP in which the PUCCH is transmitted are the same, the terminal may determine that the PDSCH is scheduled on downlink slot n+k0, i.e., slot n+3. In addition, the terminal may determine an uplink slot overlapping with the last symbol of the PDSCH scheduled on downlink slot n+3. The last symbol of PDSCH of downlink slot n+3 overlaps with uplink slot n+3. Thus, the terminal transmits PUCCH on uplink slot n+3+k1, i.e., instant slot n+5.

The terminal may determine a slot of a physical uplink control channel on which to transmit the HARQ-ACK information including the two types as follows. The terminal may determine an uplink slot overlapping with an end symbol of a Physical Downlink Control Channel (PDCCH) corresponding to HARQ-ACK information. When the index of the uplink slot is m, the slot in which the terminal transmits the uplink control channel including HARQ-ACK information may be m+k1. The index of a slot is a value based on a subcarrier spacing of an uplink BWP transmitting a Physical Uplink Control Channel (PUCCH).

Referring to fig. 14, a terminal may receive scheduling information for transmission of PUSCH and PUCCH through DCI of PDCCH, and transmit PUSCH and transmit PUCCH based on the received DCI.

As shown in fig. 14, the terminal may receive a PDCCH transmitting SPS PDSCH release DCI on downlink slot n. If K1 of DCI transmitted from the PDCCH indicates "3" and a subcarrier interval of DL BWP receiving the PDCCH and a subcarrier interval of UL BWP transmitting the PUCCH are the same, the terminal may determine an uplink slot overlapping with the last symbol of the PDCCH on the downlink slot n. In this case, the terminal may determine a PUCCH on which HARQ-ACK for transmitting SPS PDSCH release DCI is scheduled on uplink slot n+k1 (i.e., n+3).

If the terminal receives DCI format 0_0, 0_1 or 0_2 of the scheduled physical uplink shared channel, the terminal is required to transmit the scheduled uplink shared channel. For this, the terminal is required to interpret (determine) a slot of the scheduled physical uplink shared channel through DCI, and a start index and a length of a symbol in the slot. The Time Domain Resource Allocation (TDRA) field of DCI format 0_0, 0_1, or 0_2 may indicate a K2 value that is a value of information of a scheduling slot and a Start Length Indicator Value (SLIV) that is a value of information of an index and a length of a start symbol in the slot. Here, the value of K2 may be a non-negative integer value. Here, SLIV may be a value obtained by jointly encoding a value of an index of a start symbol in a slot and a value of a length (L). In addition, SLIV may separately transmit the value of the index and the value of the length (L) of the start symbol in the slot. In case of the normal CP, S may have one value among 0,1, …, 13, and L may have one value among natural numbers satisfying the condition that s+l is less than or equal to 14. S may have one value among 0,1, …, 11 in the case of the extended CP, and L may have one value among natural numbers satisfying the condition that s+l is less than or equal to 12.

The terminal may determine a time slot on which a Physical Uplink Shared Channel (PUSCH) needs to be transmitted based on the K2 value. More specifically, the terminal may determine a time slot on which a Physical Uplink Shared Channel (PUSCH) needs to be transmitted based on a K2 value, an index of a time slot in which DCI is received, a subcarrier interval of downlink BWP in which DCI is received, or a subcarrier interval of uplink BWP in which an uplink shared channel is transmitted.

For example, it is assumed that a downlink BWP receiving DCI and an uplink BWP transmitting a scheduled Physical Uplink Shared Channel (PUSCH) have the same subcarrier spacing. Suppose that DCI has been received on downlink slot n. In this case, an uplink shared channel (PUSCH) needs to be transmitted on the uplink slot n+k2.

For example, it is assumed that a subcarrier spacing of downlink BWP receiving DCI is 15khz x 2 mu_pdcch and a subcarrier spacing of uplink BWP receiving scheduled Physical Uplink Shared Channel (PUSCH) is 15khz x 2 mu_pusch. Suppose that DCI has been received on downlink slot n. The index of the downlink slot n is an index based on a subcarrier spacing of downlink BWP receiving DCI. In this case, it is necessary to transmit a Physical Uplink Shared Channel (PUSCH) on a slot floor (n 2 mu_pusch/2 mu_pdcch) +k2. The index of uplink slot floor (n x 2 mu_pusch/2 mu_pdcch) +k2 is an index based on the subcarrier spacing of the uplink BWP transmitting the uplink shared channel. In the above description, mu_pdcch or mu_pusch may have a value of 0, 1,2, or 3.

As shown in fig. 14, a terminal may receive a PDCCH scheduling a Physical Uplink Shared Channel (PUSCH) on a downlink slot n. If the value of K2 is "3" according to DCI transmitted from the PDCCH and the subcarrier spacing of DL BWP receiving the PDCCH and the subcarrier spacing of UL BWP transmitting the PUCCH are the same, the terminal may determine to schedule PUSCH on uplink slot n+k2=n+3.

The terminal may determine a symbol on which an uplink shared channel (PUSCH) needs to be transmitted in a slot on which the Physical Uplink Shared Channel (PUSCH) needs to be transmitted based on the K2 value by using a length (L) of a start symbol in the slot and an index (S). The symbols required to transmit the Physical Uplink Shared Channel (PUSCH) correspond to the symbols S to the symbols s+l-1 in the slot obtained based on the K2 value. For reference, the symbols S through S+L-1 are L consecutive symbols.

The base station may additionally configure uplink slot aggregation for the terminal. The uplink slot aggregation value may be 2,4, 8. When uplink slot aggregation is configured, a terminal is required to transmit a Physical Uplink Shared Channel (PUSCH) on consecutive slots corresponding to a slot aggregation value of slots obtained based on a K2 value.

In fig. 12 to 14, the terminal uses the K0 value, the K1 value, and the K2 value to determine a slot on which to receive a scheduled Physical Downlink Shared Channel (PDSCH) and a slot on which to transmit a Physical Uplink Control Channel (PUCCH) and a Physical Downlink Shared Channel (PDSCH). For convenience of the present invention, a slot obtained by assuming that K0 value, K1 value, and K2 value are 0 is referred to as a reference point or a reference slot.

The reference slot to which the K0 value in fig. 12 is applied is a downlink slot n, which is a slot on which the PDCCH is received.

The reference slot to which the K1 value in fig. 13 is applied is an uplink slot n+3, which is an uplink slot overlapped with the last symbol of the PDSCH.

The reference slot to which the K1 value in fig. 14 is applied is an uplink slot n, which is an uplink slot overlapping with the last symbol of the PDCCH. In addition, the reference slot to which the K2 value is applied is the uplink slot n.

In the present invention, for convenience, the following description provides an assumption that: the subcarrier spacing of downlink BWP of the terminal receiving PDSCH and PDCCH and the subcarrier spacing of uplink BWP of the terminal transmitting PUSCH and PUCCH are the same. In this case, the uplink and downlink slots are expressed by slots, not separately distinguished.

In the above description, the terminal receives one piece of DCI from the base station, and receives the PDSCH or transmits the PUSCH on one slot based on the piece of DCI. However, in the case where the base station provides the terminal with scheduling information for one slot through one DCI as described above, the base station is required to transmit a plurality of pieces of DCI the same in number as the plurality of slots, thereby scheduling the slots. This may cause waste of downlink resources.

To solve the waste, a method of receiving one piece of DCI from a base station by a terminal and receiving PDSCH on a plurality of slots based on the piece of DCI may be used. PDSCH received on each slot may include different downlink data. More specifically, PDSCH received on each slot may include different Transport Blocks (TBs). In addition, PDSCH received on each slot may have a different HARQ process number. In addition, PDSCH received on each slot may occupy different symbols in each slot.

In addition, a method of receiving one piece of DCI from a base station by a terminal and transmitting PUSCH on a plurality of slots based on the piece of DCI may be used. The PUSCH transmitted on each slot may include different uplink data. More specifically, the PUSCH transmitted on each slot may include different Transport Blocks (TBs). In addition, the PUSCH transmitted on each slot may have a different HARQ process number. In addition, the PUSCH transmitted on each slot may occupy different symbols in each slot.

As described above, for convenience, receiving PDSCH or transmitting PUSCH on a plurality of slots based on one DCI is referred to as multi-slot scheduling.

For reference, the multi-slot scheduling is different from the conventional slot aggregation (scheme of repeatedly receiving PDSCH on a plurality of slots or repeatedly transmitting PUSCH on a plurality of slots) in the following points.

The conventional slot aggregation (scheme of repeatedly receiving PDSCH on a plurality of slots or repeatedly transmitting PUSCH on a plurality of slots) is a scheme of repeatedly receiving or transmitting PDSCH or PUSCH with the same TB on a plurality of slots to amplify coverage and improve reliability. However, multi-slot scheduling is a scheme of receiving or transmitting PDSCH or PUSCH with different TBs on a plurality of slots to reduce overhead of a downlink control channel.

In the conventional downlink slot aggregation (scheme of repeatedly receiving PDSCH over a plurality of slots), PDSCH including the same TB is received over a plurality of slots, and thus whether the same TB has been successfully received is determined by PDSCH received over a plurality of slots. Therefore, the terminal is required to transmit HARQ-ACK indicating whether the one TB is successfully received to the base station. However, in multi-slot scheduling, PDSCH received on multiple slots includes different TBs, and thus a terminal is required to determine whether reception is successful for each TB. In addition, the terminal is required to transmit HARQ-ACK indicating whether or not reception is successful to the base station for each TB.

Hereinafter, scheduling of a plurality of slots will be described with reference to fig. 15 to 17.

Fig. 15 is a diagram illustrating scheduling of a downlink shared channel according to a multi-slot scheduling according to an embodiment of the present invention.

Referring to fig. 15, PDSCH reception on a plurality of slots may be scheduled for a terminal through one DCI of a PDCCH. That is, a plurality of PDSCH may be scheduled for a terminal through one DCI.

Specifically, one piece of DCI may schedule PDSCH reception on a plurality of slots. As shown in fig. 15, a PDCCH including one DCI may be received on a slot n. The Time Domain Resource Allocation (TDRA) field included in one piece of DCI may indicate a K0 value as timing information of a scheduled slot and a Start Length Indicator Value (SLIV), each of which is an index and a length of a start symbol in the slot. More specifically, PDSCH reception may be scheduled on M consecutive slots from the first slot determined by the K0 value. For example, as shown in fig. 15, if K0 is "3" and M is "3", PDSCH reception may be scheduled on slots n+3, n+4, and n+5. The index (S) of the starting symbol and the number (L) of consecutive symbols on the slot for PDSCH reception may be indicated to the terminal. The index and number of each slot may be different or the same. If the index and number of each slot are different, the index (S) of the starting symbol and the number (L) of consecutive symbols for PDSCH reception on each slot may be independently indicated.

As an example, table 4 below shows TDRA tables used in multi-slot scheduling. TDRA tables may be configured of 12 entries, and each entry may be assigned an index of 0 to 11. Each entry may schedule PDSCH on a maximum of 4 slots. To represent scheduling, each entry may be given up to 4 start and length values (SLIV) and 4K 0 values. The K0 value indicates a difference between a slot in which the PDCCH is received and a slot in which the PDCCH is received. SLIV denotes a start index (S) of a symbol of a PDSCH received in a slot and the number (L) of consecutive symbols. In [ table 4], PDSCH scheduled on one slot can be expressed by (K0, S, L).

TABLE 4

Indexing of	(K0，S，L)	(K0，S，L)	(K0，S，L)	(K0，S，L)
					0	(0，0，14)	(1，0，14)
1	(0，0，7)	(1，0，7)
					2	(0，7，7)	(1，7，7)
3	(0，0，14)	(1，0，14)	(2，0，14)	(3，0，14)
					4	(0，0，7)	(1，0，7)	(2，0，7)	(3，0，7)
5	(0，7，7)	(1，7，7)	(2，7，7)	(3，7，7)
					6	(0，0，14)	(1，0，7)
7	(0，0，14)	(1，7，7)
					8	(0，0，7)	(1，0，14)
9	(0，0，7)	(1，7，7)
					10	(0，7，7)	(1，0，14)
11	(0，7，7)	(1，0，7)

If PDSCH is schedulable on consecutive slots by multi-slot scheduling, the K0 value indicating the scheduled slot may be omitted. This is shown in Table 5 below. More specifically, each entry of the TDRA table may include only one K0 value. Furthermore, each entry may include two or more SLIV values (i.e., ((S, L)). In this case, reception of the PDSCH may be scheduled on a symbol corresponding to a first SLIV value (first (S, L)) over a slot determined from the K0 value, and reception of the PDSCH may be scheduled on a symbol corresponding to a second SLIV value (second (S, L)) over the next slot.

TABLE 5

Indexing of	K0	(S，L)	(S，L)	(S，L)	(S，L)
						0	0	(0，14)	(0，14)
1	0	(0，7)	(0，7)
						2	0	(7，7)	(7，7)
3	0	(0，14)	(0，14)	(0，14)	(0，14)
						4	0	(0，7)	(0，7)	(0，7)	(0，7)
5	0	(7，7)	(7，7)	(7，7)	(7，7)
						6	0	(0，14)	(0，7)
7	0	(0，14)	(7，7)
						8	0	(0，7)	(0，14)
9	0	(0，7)	(7，7)
						10	0	(7，7)	(0，14)
11	0	(7，7)	(0，7)

If PDSCH is schedulable on non-consecutive slots by multi-slot scheduling, a K0 value indicating a scheduled slot and an offset value for a slot of the K0 value may be included. The offset value indicates the difference between the time slot indicated by the K0 value and the time slot indicated for reception. This is shown in [ Table 6 ]. More specifically, each entry of the TDRA table may include only one K0 value. Each SLIV may additionally have an offset value ([ table 6] of O). For reference, in SLIV of the time slot of the K0 value, the offset value may be omitted.

TABLE 6

Indexing of	K0	(O，S，L)	(O，S，L)	(O，S，L)	(O，S，L)
						0	0	(0，0，14)	(1，0,14)
1	0	(0，0，7)	(1，0，7)
						2	0	(0，7，7)	(1，7，7)
3	0	(0，0，14)	(1，0，14)	(2，0，14)	(3，0，14)
						4	0	(0，0，7)	(1,0,7)	(2,0，7)	(3,0,7)
5	0	(0,7,7)	(1,7,7)	(2，7,7)	(3,7,7)
						6	0	(0，0,14)	(1,0,7)
7	0	(0,0,14)	(1,7,7)
						8	0	(0,0,7)	(1,0,14)
9	0	(0,0,7)	(1,7,7)
						10	0	(0，7，7)	(1，0，14)
11	0	(0，7，7)	(1，0，7)

In the present invention, for convenience of explanation, a case of scheduling PDSCH on a plurality of consecutive slots is described. Thus, unless otherwise indicated, the value of K0 is omitted. However, the present invention also includes the case of scheduling PDSCH on multiple non-contiguous slots.

Fig. 16 is a diagram illustrating uplink control channel transmission in one slot according to multi-slot scheduling according to an embodiment of the present invention.

Referring to fig. 16, PDSCH reception on a plurality of slots may be scheduled for a terminal through one DCI of a PDCCH, and HARQ-ACKs of the scheduled plurality of PDSCH may be transmitted on one slot through a PUCCH.

Specifically, HARQ-ACKs scheduled by one DCI to PDSCH received on a plurality of slots may be transmitted on one slot through the PUCCH. An uplink slot overlapping with an end time point of a last PDSCH among PDSCH received on the plurality of slots may be determined as an uplink slot having a K1 value of 0. In fig. 16, the uplink slot n+5 is an uplink slot with a K1 value of 0 and may be referred to as a reference slot. A K1 value may be indicated from a piece of DCI to the terminal. In this case, the terminal may transmit HARQ-ACKs scheduled by one DCI for PDSCH received on a plurality of slots on uplink slots corresponding to one K1 value.

That is, the terminal may be scheduled with one DCI for reception of multiple PDSCH on multiple slots and transmission of HARQ-ACK on one slot. The terminal may determine a first slot for transmitting a plurality of PDSCHs through a K0 value of DCI and determine one slot for transmitting HARQ-ACKs for the plurality of PDSCHs through a K1 value by using a slot on which a last PDSCH of the plurality PDSSCH has been transmitted as a reference slot.

Fig. 17 is a diagram illustrating uplink control channel transmission in two or more slots according to a multi-slot schedule according to an embodiment of the present invention.

Referring to fig. 17, PDSCH reception on a plurality of slots may be scheduled for a terminal through one DCI of a PDCCH, and HARQ-ACKs of the scheduled plurality of PDSCH may be transmitted on two or more slots through a PUCCH.

Specifically, HARQ-ACKs scheduled by one DCI for multiple PDSCH received on multiple slots may be transmitted on two or more slots through PUCCH. In this case, first, PDSCH scheduled to be received on a plurality of slots by one DCI may be grouped into two or more groups. For example, a plurality of PDSCH may be grouped into two or more groups according to time sequence, and PDSCH that is consecutive in time sequence (i.e., time sequence) may be grouped into one group. As shown in fig. 17, one piece of DCI may schedule reception of PDSCH on 3 slots, group the first 2 PDSCH among PDSCH of 3 slots into one group (group 0), and group the last 1 PDSCH into one group (group 1). The detailed grouping method is as follows.

As a first method, a terminal may group PDSCH based on the number of PDSCH scheduled by one DCI. The number of PDSCH of a packet may be limited to a predetermined number. Thus, PDSCH may be grouped by a predetermined number and one or more groups may be generated. For example, if the predetermined number is 2 and the number of PDSCH is 4, the 4 PDSCH may be grouped into groups including 2 PDSCH per group. The predetermined number may be configured by the base station.

As a second method, the terminal may perform grouping based on the number of groups predetermined by one piece of DCI. That is, the base station may configure a predetermined number of groups for the terminal. For example, if the predetermined number of groups is 2 and the number of PDSCH scheduled by one DCI is 6, 6 PDSCH may be divided into 2 groups. PDSCH may be sequentially divided into groups over time, PDSCH included in each group may be equal in number as much as possible, and the maximum number difference between them may reach 1.

As a third method, a grouping of each entry in TDRA can be configured for the terminal. More specifically, each entry in TDRA includes information for PDSCH reception over multiple slots. Here, information about a slot whose PDSCH is grouped into a group may be included. That is, SLIV indicating PDSCH reception per slot and an index of a group including SLIV may be included together. Referring to [ Table 7], an index (G) of the group including SLIV may be included in each entry of the TDRA table. SLIV belonging to g=0 corresponds to group 0, and SLIV belonging to g=1 corresponds to group 1.

TABLE 7

Indexing of	(K0，S，L，G)	(K0，S，L,G)	(K0,S,L,G)	(K0,S,L,G)
					0	(0,0,14,0)	(1,0,14,0)
1	(0,0,7,0)	(1,0,7,0)
					2	(0，7，7,0)	(1,7,7,0)
3	(0,0,14,0)	(1,0,14,0)	(2，0，14，1)	(3，0，14，1)
					4	(0，0，7，0)	(1，0，7，0)	(2，0，7，1)	(3，0，7，1)
5	(0，7，7，0)	(1，7，7，0)	(2，7，7，1)	(3，7，7，1)
					6	(0,0,14，0)	(1，0，7，0)
7	(0，0，14，0)	(1,7,7,0)
					8	(0,0,7,0)	(1,0,14,0)
9	(0,0,7,0)	(1，7，7，0)
					10	(0，7，7，0)	(1,0,14,0)
11	(0，7，7，0)	(1，0，7，0)

The terminal may transmit HARQ-ACKs of PDSCH included in one group through PUCCH of the uplink slot. As a method of determining the uplink slot, an uplink slot overlapping with the end time point of the last PDSCH included in the group and having a K1 value of 0 may be determined as the reference slot. That is, in fig. 17, the reference slot of group 0 is slot n+4, and the reference slot of group 1 is slot n+5.

A K1 value may be indicated from a piece of DCI to the terminal. In this case, the terminal may transmit HARQ-ACKs scheduled by one DCI for PDSCH received on a plurality of slots on uplink slots corresponding to one K1 value for each group. For example, in fig. 17, K1 is equal to 2 (k1=2). HARQ-ACKs for two PDSCH included in group 0 are transmitted on PUCCH of slot n+4+2 (=reference slot index+k1 of group 0), and HARQ-ACKs for one PDSCH included in group 1 are transmitted on PUCCH of slot n+7 (=reference slot index+k1 of group 1).

One K1 value per group may be indicated from one piece of DCI to the terminal. In this case, for each group, the terminal may transmit HARQ-ACKs scheduled by one piece of DCI for PDSCH received on a plurality of slots on uplink slots corresponding to K1 of the corresponding group. For example, 1 may be given as a K1 value for group 0 and 2 may be given as a K1 value for group 1. In this case, HARQ-ACKs of two PDSCH included in group 0 are transmitted on PUCCH of slot n+4+k1 (=reference slot index of group 0+k 1 of group 0), and HARQ-ACKs of one PDSCH included in group 1 are transmitted on PUCCH of slot n+7 (=reference slot index of group 1+k 1 of group 1).

In the present invention, a method of transmitting HARQ-ACK of PDSCH when PDSCH is scheduled by multi-slot scheduling is described.

A terminal in an NR wireless communication system may transmit a codebook including hybrid automatic repeat request (HARQ-ACK) information to transmit signaling regarding whether reception of a downlink signal or channel is successful. The HARQ-ACK codebook includes one or more bits indicating whether the reception of a downlink channel or signal is successful. Here, the downlink channel may include at least one of a Physical Downlink Shared Channel (PDSCH), a semi-persistent scheduling (SPS) PDSCH, and a PDSCH releasing the SPS PDSCH. The HARQ-ACK codebook may be classified into a semi-static HARQ-ACK codebook and a dynamic HARQ-ACK codebook. The base station may configure one of two HARQ-ACK codebooks for the terminal. The terminal may use a HARQ-ACK codebook configured for the terminal.

Type-1 HARQ-ACK codebook

Let us assume that terminals are configured with 1 and 2 as K1 values. In the case of configuring the TDRA table as shown in [ table 4], when PUCCH is transmitted on slot n, PDSCH candidates corresponding to HARQ-ACKs required to be transmitted through the PUCCH are illustrated in fig. 18.

In case of using a type-1 HARQ-ACK codebook (semi-static HARQ-ACK codebook), the base station may configure the number of bits of the HARQ-ACK codebook and information related to a channel or signal, whether or not reception thereof is successful, by each bit of the HARQ-ACK codebook using an RRC signal. Thus, the base station does not need to transmit signaling related to information required for HARQ-ACK codebook transmission to the terminal every time the HARQ-ACK codebook transmission is required.

More specifically, the method of generating the type-1 HARQ-ACK codebook is as follows. The type-1 HARQ-ACK codebook is transmitted on slot n.

1) A set of indicated K1 values is named k1_set. The largest K1 value is retrieved from k1_set. This value is denoted k1_max. The K1 value is excluded from k_set.

2) The set of PDSCH candidates that may be received on slot n-k1_max is referred to as R. The PDSCH candidates included in set R have a starting symbol and length received on a slot according to TDRA table. When the symbols of the PDSCH candidates included in the set R overlap with the symbols configured as uplink in the semi-static UL/DL configuration, the PDSCH candidates are excluded from the set R.

3) The terminal performs the following steps a and B on PDSCH candidates included in R.

A) A new HARQ-ACK opportunity is allocated to a PDSCH candidate having the most front last symbol among PDSCH candidates of the set R. Then, if the set R includes PDSCH candidates (at least one symbol of which overlaps with the PDSCH candidate having the foremost last symbol), the same HARQ-ACK occasion is allocated to the PDSCH candidate. PDSCH candidates to which HARQ-ACK opportunities are allocated (PDSCH candidates having the foremost last symbol and PDSCH candidates whose at least one symbol overlaps with the PDSCH candidates) are excluded from the set R.

B) Step 3-a is repeated until set R becomes an empty set.

4) Processes 1), 2) and 3) are repeated until k1_set becomes an empty set.

The terminal may generate a type-1 HARQ-ACK codebook based on the HARQ-ACK occasions. If the terminal has received DCI of a scheduling PDSCH or a semi-persistent scheduling (SPS) PDSCH, the terminal may transmit HARQ-ACK information of the PDSCH in HARQ-ACK occasions of the PDSCH. The HARQ-ACK occasion may be configured as NACK if the terminal fails to receive any one of the PDSCH corresponding to one HARQ-ACK occasion.

For reference, the HARQ-ACK occasion may include 1 bit ACK/NACK or a plurality of bits ACK/NACK. For example, if the PDSCH of the terminal includes 1 TB, 1-bit ACK/NACK may be included in the HARQ-ACK occasion, and if the PDSCH includes 2 TBs, 2-bit ACK/NACK may be included in the HARQ-ACK occasion. Further, if reception of a Code Block Group (CBG) -based PDSCH is configured for a terminal, ACK/NACK corresponding to the maximum number of CBGs that one PDSCH may include may be included in the HARQ-ACK occasion.

Hereinafter, in the present invention, for convenience of explanation, 1 bit per HARQ-ACK occasion is assumed.

The problem to be solved by the present invention relates to a method of generating a type-1 HARQ-ACK codebook (semi-static HARQ-ACK codebook) when PDSCH is scheduled by multi-slot scheduling.

First embodiment: PDSCH candidates in time slots

The first embodiment of the present invention is a method of converting PDSCH scheduled by multi-slot scheduling into PDSCH candidates of each slot and generating a type-1 HARQ-ACK codebook by using the PDSCH candidates in each slot. More specifically, the type-1 HARQ-ACK codebook generating method according to the first embodiment is as follows.

1) Step 1: a set of indicated K1 values is named k1_set. The terminal may determine an index of a slot receiving a PDSCH candidate that needs to be included in the type-1 HARQ-ACK codebook based on the k1_set and TDRA table. A set of indices is called K slot.

More specifically, the method of determining the index set K slot is as follows. A K1 value may be selected from k1_set. The selected value of K1 is K1_a. The terminal may determine a slot on which the PDSCH needs to be received based on the k1_a value and TDRA table. For example, if TDRA table includes PDSCH allocation information of up to N consecutive slots, the PDSCH allocation information may be determined as PDSCH allocation information of slot N-k1_a- (N-1), slot N-k1_a- (N-2), … …, and slot N-k1_a. Thus, the K_slot set may include K1_a+ (N-1), K1_a+ (N-2), …, K1_a. (for reference, TDRA table may include PDSCH allocation information of non-consecutive slots.) in this case, N is the number of slots from the earliest scheduled slot to the latest scheduled slot among the slots scheduled in TDRA table, and unscheduled slots in TDRA table between slots N-k1_a- (N-1) to N-k1_a may be excluded.

As described above, indexes of slots on which PDSCH candidates can be received may be obtained for all K1 values of k1_set, and collected and included in the k_slot set.

2) Step 2: the largest K1 value is retrieved from k_slot. This value is denoted k1_max. The K1 value is excluded from k_slot.

3) Step 3: the set of PDSCH candidates that may be received on slot n-k1_max is referred to as R. When the symbols of the PDSCH candidates included in the set R overlap with the symbols configured as uplink in the semi-static UL/DL configuration, the PDSCH candidates are excluded from the set R.

PDSCH candidates included in set R may be obtained as follows. A K1 value may be selected from k1_set. The selected value of K1 is K1_a. The terminal may determine PDSCH candidates on slot n-k1_max based on the k1_a value and TDRA table. For example, if one entry of the TDRA table includes PDSCH allocation information of at most M consecutive slots, the PDSCH allocation information may be determined as PDSCH allocation information of slot n-k1_a- (M-1), slot n-k1_a- (M-2),. And slot n-k1_a. If one slot among the slots n-k1_a- (M-1), n-k1_a- (M-2), …, and n-k1_a is the slot n-k1_max, the PDSCH candidate included in the slot may be included in the R set. The above procedure is performed for all entries of the TDRA table, or for all K1 values of k1_set.

4) Step 4: the terminal performs the following steps a and B on PDSCH candidates included in R.

A) A new HARQ-ACK opportunity is allocated to a PDSCH candidate having the most front last symbol among PDSCH candidates of the set R. Then, if the set R includes PDSCH candidates (at least one symbol of which overlaps with the PDSCH candidate having the foremost last symbol), the same HARQ-ACK occasion is allocated to the PDSCH candidates. PDSCH candidates to which HARQ-ACK opportunities are allocated (PDSCH candidates having the foremost last symbol and PDSCH candidates whose at least one symbol overlaps with the PDSCH candidates) are excluded from the set R.

B) Step 4-a is repeated until set R becomes an empty set.

5) Step 5: the steps 2/3/4 are repeated until the K1_slot becomes an empty set.

Fig. 19 is a diagram illustrating HARQ-ACK occasions according to an embodiment of the present invention.

Referring to fig. 19, PDSCH scheduled by multi-slot scheduling is converted into PDSCH candidates of each slot, and a type-1 HARQ-ACK codebook may be generated by using the PDSCH candidates in each slot.

Specifically, the type-1 HARQ-ACK codebook may be generated through the following 5 steps as shown in fig. 19.

1) Step 1: terminals are assigned 1 and 2 as the value of K1 and thus k1_set is equal to 1 and 2 (k1_set=1, 2). The terminal may determine k1_slot through the following procedure.

A value may be selected in k1_set. For example, if k1_a, which is a value selected in k1_set, is "2", each entry of the TDRA table includes PDSCH allocation information for a maximum of N consecutive slots (n=4), the terminal may determine the PDSCH allocation information as PDSCH allocation information of slot N-k1_a- (N-1) =n-2- (4-1) =n-5, slot N-k1_a- (N-2) =n-2- (4-2) =n-4, slot N-k1_a- (N-3) =n-2- (4-3) =n-3, and slot N-k1_a=n-2. Thus, k1_slot includes 5, 4, 3, 2.

Thereafter, if the remaining one value is selected in k1_set and the selected value k1_a is "1", each entry of the TDRA table includes PDSCH allocation information for a maximum of N consecutive slots (n=4), the terminal may determine PDSCH allocation information as PDSCH allocation information of slots N-k1_a- (N-1) =n-1- (4-1) =n-4, slots N-k1_a- (N-2) =n-1- (4-2) =n-3, slots N-k1_a- (N-3) =n-1- (4-3) =n-2, and slots N-k1_a=n-1. Thus, k1_slot includes 4, 3, 2, 1.

Thus, k1_slot includes 5, 4, 3, 2, and 1.

2) Step 2: k1_max=5, and the maximum value is selected among k1_slots. The K1 value is excluded from k1_slot.

3) Step 3: the set of PDSCH candidates that can be received on slot n-k1_max=n-5 is referred to as R. When the symbols of the PDSCH candidates included in the set R overlap with the symbols configured as uplink in the semi-static UL/DL configuration, the PDSCH candidates are excluded from the set R. Here, it is assumed that all symbols are downlink symbols.

The PDSCH candidates included in set R on slot n-5 may be obtained as follows.

A value is selected in k1_set. This value is denoted k1_a=2. Entries 3, 4 and 5 of the TDRA table include PDSCH allocation information of 4 consecutive slots, 4 consecutive slots including slot n-k1_a- (M-1) =n-5, slot n-k1_a- (M-2) =n-4, … and slot n-k1_a=n-2, and the remaining entries (0,1,2,6,7,8,9,10 and 11) include PDSCH allocation information of 2 consecutive slots including slot n-3 and slot n-2. Thus, entries 3, 4 and 5 of the TDRA table include PDSCH candidates for time slot n-k1_max=n-5, and thus PDSCH candidates included in that time slot may be included in set R. That is, the set R of PDSCH candidates that may be received on the slot n-k1_max=n-5 may include the following portions. The set R may include (s=0, l=14), (s=0, l=7) and (s=7, l=7). For reference, (s=0, l=14) is the PDSCH candidate on slot n-5 in entry 3 of TDRA table, (s=0, l=7) is the PDSCH candidate on slot n-5 in entry 4 of TDRA table, and (s=7, l=7) is the PDSCH candidate on slot n-5 in entry 5 of TDRA table.

The remaining one value is selected in k1_set. This value is denoted k1_a=1. Entries 3, 4 and 5 of the TDRA table include PDSCH allocation information of 4 consecutive slots including slot n-k1_a- (M-1) =n-4, slot n-k1_a- (M-2) =n-3, … and slot n-k1_a=n-1, and the remaining entries (0,1,2,6,7,8,9,10 and 11) include PDSCH allocation information of 2 consecutive slots including slot n-2 and slot n-1. Therefore, the slot corresponding to k1_a=1 does not overlap with the slot n-k1_max=n-5, and thus PDSCH candidates are not included in the set R.

Thus, R equals (s=0, l=14), (s=0, l=7) and (s=7, l=7).

A) HARQ-ACK occasion 0 is allocated (s=0, l=7), which is a PDSCH candidate having the most front last symbol among PDSCH candidates of the set R. Then, the same HARQ-ACK opportunity is allocated to PDSCH candidates (s=0, l=14), at least one symbol of which overlaps with PDSCH candidates (s=0, l=7) having the foremost last symbol in the set R. Excluding (s=0, l=7) and (s=0, l=14) from the set R, which are PDSCH candidates to which HARQ-ACK occasions are allocated. Thus, the set R is equal to (s=7, l=7).

B) Step 4-a is repeated until set R becomes an empty set.

Set R is not an empty set and therefore step 4-A is repeated again. According to step 4-a, HARQ-ACK occasion 1 is allocated to PDSCH candidates (s=7, l=7) and set R becomes an empty set. Thus, step 4 ends.

5) Step 5: the steps 2/3/4 are repeated until the K1_slot becomes an empty set.

K1_slot=4, 3,2,1, and is therefore not an empty set. K1_slot is not an empty set, so step 2/3/4 is repeated again.

According to these steps, PDSCH candidates and HARQ-ACK opportunities are determined as follows.

HARQ-ACK occasion 0: PDSCH candidates of slot n-5 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 1: PDSCH candidate of slot n-5 (s=7, l=7)

HARQ-ACK occasion 2: PDSCH candidates of slot n-4 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 3: PDSCH candidate of slot n-4 (s=7, l=7)

HARQ-ACK occasion 4: PDSCH candidates of slot n-3 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 5: PDSCH candidate of slot n-3 (s=7, l=7)

HARQ-ACK occasion 6: PDSCH candidates of slot n-2 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 7: PDSCH candidate of slot n-2 (s=7, l=7)

HARQ-ACK occasion 8: PDSCH candidates of slot n-1 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 9: PDSCH candidate of slot n-1 (s=7, l=7)

Thus, a type-1 HARQ-ACK codebook may be configured by 10 HARQ-ACK occasions.

For example, assume that DCI received by a terminal has indicated entry 4 of TDRA table and k1=2. In this case, the terminal receives the first PDSCH (s=0, l=7) on the slot n-5, the second PDSCH (s=0, l=7) on the slot n-4, the third PDSCH (s=0, l=7) on the slot n-3, and the fourth PDSCH (s=0, l=7) on the slot n-2. The terminal includes HARQ-ACK (o ₁) of the first PDSCH in HARQ-ACK occasion 0, HARQ-ACK (o ₂) of the second PDSCH in HARQ-ACK occasion 2, HARQ-ACK (o ₃) of the third PDSCH in HARQ-ACK occasion 4, and HARQ-ACK (o ₄) of the fourth PDSCH in HARQ-ACK occasion 6. Thus, the type-1 HARQ-ACK codebook is [ o 1N o 2N o 3N o N4N ]. Here, N represents NACK.

In addition, assume that DCI received by a terminal has indicated entry 5 of TDRA table and k1=1. In this case, the terminal receives the fifth PDSCH (s=7, l=7) on the slot n-4, the sixth PDSCH (s=7, l=7) on the slot n-3, the seventh PDSCH (s=7, l=7) on the slot n-2, and the eighth PDSCH (s=7, l=7) on the slot n-1. The terminal includes HARQ-ACK (o ₅) of the fifth PDSCH in HARQ-ACK occasion 3, HARQ-ACK (o ₆) of the sixth PDSCH in HARQ-ACK occasion 5, HARQ-ACK (o ₇) of the seventh PDSCH in HARQ-ACK occasion 7, and HARQ-ACK (o ₈) of the eighth PDSCH in HARQ-ACK occasion 9. Thus, the type-1 HARQ-ACK codebook is [ o 1N o o2 o5 o3 o6 o4 o 7N o ]. Here, N represents NACK.

In a first embodiment of the present invention, the PDSCH candidates in each slot are used to generate HARQ-ACK opportunities. However, one DCI can schedule PDSCH on multiple slots, so generating HARQ-ACK opportunities by using PDSCH candidates for each slot may be inefficient. For example, referring to fig. 19, a maximum of 8 PDSCH may be scheduled for a terminal in any case. This case corresponds to the following section.

(TDRA table entry 4 and k1=2, tdra table entry 5 and k1=2)

(TDRA table entry 4 and k1=2, tdra table entry 5 and k1=1)

(TDRA table entry 4 and k1=1, tdra table entry 5 and k1=2)

(TDRA table entries 4 and k1=1, tdra table entries 5 and k1=1)

Therefore, the type-1 HARQ-ACK codebook transmitted by the terminal needs to include 8 HARQ-ACK occasions. However, as described above, in this case, 10 HARQ-ACK opportunities are included. The 2 HARQ-ACK occasions are not always used for transmitting HARQ-ACK information.

Second embodiment: PDSCH candidates in all slots

A second embodiment of the present invention is a method of generating a type-1 HARQ-ACK codebook by using PDSCH candidates in all slots. More specifically, the type-1 HARQ-ACK codebook generating method according to the second embodiment is as follows.

1) Step 1: the terminal may include schedulable PDSCH candidate pairs in the set R. The PDSCH candidate pair is obtained by grouping PDSCH candidates schedulable according to entries of the TDRA table. Thus, a PDSCH candidate pair indicates that it receives PDSCH candidates that are schedulable over multiple slots. In addition, when a symbol of a PDSCH candidate included in the PDSCH candidate pair included in the set R overlaps with a symbol configured as an uplink in the semi-static UL/DL configuration, the PDSCH candidate is excluded from the PDSCH candidate pair. If all PDSCH candidates are excluded from one PDSCH candidate pair, then that PDSCH candidate pair is excluded from set R.

2) Step 2: the terminal performs the following steps a and B on PDSCH candidate pairs included in the set R.

A) One PDSCH candidate pair is retrieved from the PDSCH candidate pairs of set R. A new HARQ-ACK opportunity is allocated to the PDSCH candidate pair. Then, if the set R includes PDSCH candidate pairs whose at least one symbol overlaps with PDSCH candidates, the same HARQ-ACK opportunity is allocated to the PDSCH candidate pairs. PDSCH candidate pairs to which HARQ-ACK opportunities are allocated are excluded from set R.

B) Step 2-a is repeated until set R becomes an empty set.

Unlike the first embodiment, in the second embodiment, PDSCH candidates correspond to HARQ-ACK occasions. Each PDSCH candidate pair may include a different number of PDSCH candidates. Thus, the number of PDSCH candidates that need to be indicated for one HARQ-ACK occasion may be different. For this, the number of PDSCH candidates to be indicated by one HARQ-ACK occasion is determined based on the maximum number of PDSCH candidates with respect to the PDSCH candidate pair corresponding to the HARQ-ACK occasion.

In step 2-a, the terminal is required to select one PDSCH candidate pair in the set R. For this purpose, at least the following methods or combinations of the same methods can be considered.

As a first method, the terminal may select a PDSCH candidate pair including the earliest starting PDSCH candidate. Therefore, HARQ-ACK opportunities are preferentially allocated to PDSCH candidates at the earliest time point in time order.

As a second method, the terminal may select the PDSCH candidate pair whose end time point is earliest. Therefore, the HARQ-ACK opportunity is preferentially allocated to the PDSCH candidate that ends chronologically earliest.

As a third method, the terminal may select a PDSCH candidate pair having the least symbol. Therefore, the PDSCH candidate pair is least likely to overlap with another PDSCH candidate pair.

As a fourth method, the terminal may select a PDSCH candidate pair having the most symbol. Accordingly, the PDSCH candidate pair overlaps with the most PDSCH candidate pair, and thus a large number of PDSCH candidates can be excluded from the set R.

As a fifth method, the terminal may select a PDSCH candidate pair having the most slots. As described above, the HARQ-ACK opportunity is determined according to the number of PDSCH candidates included in the PDSCH candidate pair, and thus a PDSCH candidate pair with fewer slots overlapping with a PDSCH candidate pair with more slots can be searched.

As a sixth method, the terminal may select a PDSCH candidate pair having the lowest index of TDRA tables. This may be configured by the base station when configuring TDRA tables.

Fig. 20 is a diagram illustrating a time domain bundling window according to an embodiment of the present invention.

Time domain bundling

When the terminal generates the type-1 HARQ-ACK codebook, it may be configured with time domain bundling. Time domain bundling is a method of bundling HARQ-ACKs of respective PDSCH into one HARQ-ACK bit (one HARQ-ACK bit is generated using HARQ ACK through binary and operation, i.e., if HARQ ACKs are all ACKs, the one HARQ ACK bit is ACK, and otherwise, the one HARQ-ACK bit is NACK) and transmitting the same. PDSCH may be PDSCH on the same slot or PDSCH on a different slot. PDSCH is a PDSCH scheduled by one DCI and a PDSCH adjacent when PDSCH is chronologically arranged. For example, when one DCI scheduled PDSCH is pdsch#0 on slot n, pdsch#1 on slot n+1, pdsch#2 on slot n+2, pdsch#3 on slot n+3, the terminal may bundle HARQ-ACKs of pdsch#0 on slot n and pdsch#1 on slot n+1 in 4 PDSCHs into one HARQ-ACK bit, and bundle HARQ-ACKs of pdsch#2 on slot n+2 and pdsch#3 on slot n+3 into one HARQ-ACK bit. Thus, 4 HARQ-ACK bits are generated for 4 PDSCH, but only 2 HARQ-ACK bits may be transmitted through time domain bundling.

The base station may configure the terminal with at least one of the following information for time domain bundling.

As the first information, the base station may configure the number of HARQ-ACKs (or the number of PDSCH) of the PDSCH to be bundled for time domain bundling. This is named N _bundle.N_bundle, which may be one of 2,4, 8. If the terminal is configured with N _bundle, the terminal bundles HARQ-ACKs of N _bundle PDSCHs into 1 HARQ-ACK bit and transmits it. Assume that a terminal schedules M PDSCH through one DCI. If M is a multiple of N _bundle (M mod N _bundle =0), the terminal may bundle N _bundle PDSCHs to generate one bundled HARQ-ACK, thereby generating a total of M/N _bundle bundled HARQ-ACKs. However, if M is not a multiple of N _bundle (M mod N _bundle > 0), the terminal may bundle PDSCH as follows. For reference, pdsch#0, pdsch#1, …, and pdsch# (M-1) are arranged in time series.

As a first method, N _bundle PDSCHs are chronologically bundled to generate one bundled HARQ-ACK. If the number of remaining PDSCHs is less than N _bundle, the remaining PDSCHs are bundled to generate 1 bundled HARQ-ACKs. More specifically, pdsch#0, pdsch#1, …, and pdsch# (N _bundle -1) are bundled to generate one bundled HARQ-ACK. Pdsch# (N _bundle)、PDSCH#(N_bundle + 1), …, and pdsch# (2*N _bundle -1) are bundled to generate one bundled HARQ-ACK. Continuing with bundling as described above, pdsch# (floor (M/N _bundle)*N_bundle)、PDSCH#(floor(M/N_bundle)*N_bundle +1), … and pdsch# (M-1) are bundled to generate one bundled HARQ-ACK. As a result, a total of ceil (M/N _bundle) bundled HARQ-ACK bits are generated.

As a second method, PDSCH is time-sequentially bundled to form k=ceil (M/N _bundle) groups. The number of PDSCHs included in each group may be ceil (M/K) or floor (M/K). The Ceil (M/K) PDSCHs are time-sequentially bundled to form M mod K groups, and then the floor (M/K) PDSCHs are time-sequentially bundled to form K- (M mod K) groups. The HARQ-ACKs in each group are bundled to generate one bundled HARQ-ACK. As a result, a total of ceil (M/N _bundle) bundled HARQ-ACK bits are generated.

As the second information, the base station may configure the number of bundled HARQ-ACKs (or the number of PDSCH groups) for the time domain bundling. This is named N _group.N_group, which may be one of 2,4 and 8. If N _group is configured for the terminal, the terminal may bundle M PDSCH to form N _group PDSCH groups. For reference, if M is less than N _group, the terminal bundles one PDSCH to form M PDSCH groups, and the next N _group -M groups do not include PDSCH. The HARQ-ACK of the group excluding the PDSCH may be configured as NACK. The HARQ-ACK of the group excluding the PDSCH may not be transmitted to the base station.

As a first method, k=ceil (M/N _group) PDSCH are bundled in time order to generate one bundled HARQ-ACK. If the number of remaining PDSCHs is less than K, the remaining PDSCHs are bundled to generate one bundled HARQ-ACK. More specifically, pdsch#0, pdsch#1, …, and pdsch# (K-1) are bundled to generate one bundled HARQ-ACK. Pdsch# (K), pdsch# (k+1), …, and pdsch# (2*K-1) are bundled to generate one bundled HARQ-ACK. Continuing with bundling as described above, pdsch# (floor (M/K) ×k), pdsch# (floor (M/K) ×k+1), …, and pdsch# (M-1) are bundled to generate one bundled HARQ-ACK. As a result, a total of N _group bundled HARQ-ACK bits are generated.

As a second method, PDSCH is time-sequentially bundled to form N _group groups. The number of PDSCHs included in each group may be ceil (M/N _group) or Floor (M/N _group).Ceil(M/N_group) PDSCHs chronologically bundled to form M mod N _group groups, and then Floor (M/N _group) PDSCHs chronologically bundled to form N _group-(M mod N_group groups. The HARQ-ACKs in each group are bundled to generate one bundled HARQ-ACK. As a result, a total of N _group bundled HARQ-ACK bits are generated.

As the third information, the base station may configure a time interval for time domain bundling. The time interval can be configured in units of time slots. This time interval may be referred to as a bundling window. The time interval (bundling window) configured in units of slots is called N _slot. The terminal may bundle PDSCH included in N _slot slots to form a group. If one or more PDSCHs are included in the group, the terminal may bundle the HARQ-ACKs of the PDSCHs into one HARQ-ACK. The HARQ-ACK of the group excluding the PDSCH may be configured as NACK. The HARQ-ACK of the group excluding the PDSCH may not be transmitted to the base station. The terminal may determine N _slot slots as follows.

As a first method, a terminal may bundle PDSCH included in every N _slot consecutive slots starting at slot 0 of a frame together to form a group. That is, PDSCH included in time slots i×n _slot, time slots i×n _slot +1, …, and time slot (i+1) ×n _slot -1 may be bundled to form a group. Here, i is an integer.

As a second method, the terminal may bundle PDSCH included in every N _slot consecutive slots starting from slot k of the frame to form a group. That is, PDSCH included in time slots i×n _slot +k, time slots i×n _slot +k+1, …, and time slot (i+1) ×n _slot -1+k may be bundled to form a group. For reference, PDSCH included in slot 0, slot 1, …, and slot k-1 may be bundled to form a group. Here, i is an integer. Here, k may be a value configured by the base station for the terminal, k may be a value determined based on an index of a slot in which the first PDSCH is scheduled, k may be a value determined based on an index of a slot in which the PDCCH of the PDSCH is scheduled to be transmitted, or k may be a value determined based on an index of a slot in which the PUCCH including the HARQ-ACK of the PDSCH is transmitted.

For example, if the value determined based on the index of the slot scheduling the first PDSCH is X, k may be equal to X. The first PDSCH is scheduled on the slot 3, and thus PDSCH included in the slots 3,4,5, and 6, which are N _slot =4 slots starting from the slot 3, are bundled to form one group, and the next N _slot =4 slots including the slots 7, 8, 9, and 10 may be bundled to form one group.

For example, if the value determined based on the index of the slot of the PDCCH on which the scheduled PDSCH is transmitted is X, k may be equal to X. PDCCH is scheduled on slot 1, so PDSCH included in slot 1, slot 2, slot 3, slot 4, which are N _slot =4 slots from slot 1, is bundled to form one group, and next N _slot =4 slots including slot 5, slot 6, slot 7, slot 8 may be bundled to form one group.

For example, if an index of a slot of a PUCCH on which HARQ-ACK including PDSCH is transmitted is X, k may be equal to X mod N _slot. PUCCH is scheduled on slot 10 and k=10mod 4 is equal to 2, so PDSCH included in slot 2, slot 3, slot 4, and slot 5, which are N _slot =4 slots starting from slot 2, is bundled to form one group, and the next N _slot =4 slots including slot 6, slot 7, slot 8, and slot 9 may be bundled to form one group.

For example, as shown in FIG. 20, if N _slot is configured as "3" and k is equal to N-5, then the slots from slot N-5 may be bundled to configure a bundling window that includes 3 slots each. That is, the slot n-5, the slot n-4, and the slot n-3 are included in one bundling window (bundling window #a), and the slot n-2, the slot n-1, and the slot n are included in another bundling window (bundling window #b). Accordingly, the PDSCH included in the bundling window #a may be bundled to generate one bundled HARQ-ACK bit, and the PDSCH included in the bundling window #b may be bundled to generate one bundled HARQ-ACK bit.

The problem to be solved by the present invention relates to a method of generating a type-1 HARQ-ACK codebook by a terminal when configuring time domain bundling as described above for the terminal.

For explanation, in the present invention, it is assumed that a terminal has generated a group including PDSCH bundled based on first information, second information, or third information. For convenience, the PDSCH included in the group are PDSCH#n, PDSCH# (n+1), …, and PDSCH# (n+k-1). The number of PDSCH included in the group is k.

As a preferred first embodiment of the present invention, the terminal may select one from PDSCH included in the group as a representative. The terminal may generate a type-1 HARQ-ACK codebook based on SLIV corresponding to the PDSCH.

The method of selecting one from PDSCH included in the group as a representative may include at least one of the following.

As the first method, a chronologically forefront PDSCH among PDSCH included in the group may be selected. For example, if PDSCH included in the group is pdsch#n, pdsch# (n+1), …, and pdsch# (n+k-1), pdsch#n may be selected.

As the second method, a PDSCH chronologically last among PDSCH included in the group may be selected. For example, if PDSCH included in the group is pdsch#n, pdsch# (n+1), …, and pdsch# (n+k-1), pdsch# (n+k-1) may be selected.

As a third method, a PDSCH occupying the most symbols among PDSCH included in the group may be selected. If multiple PDSCH occupy the same number of symbols, the temporally front-most or rear-most PDSCH may be selected therefrom.

As a fourth method, a PDSCH occupying the least symbol among the PDSCHs included in the group may be selected. If multiple PDSCH occupy the same number of symbols, the temporally front-most or rear-most PDSCH may be selected therefrom.

As a fifth method, PDSCH whose at least one symbol overlaps with a UL symbol according to a semi-static UL/DL configuration may be excluded from PDSCH of the first, second, third, and fourth methods.

Fig. 21 is a diagram illustrating a representative PDSCH according to a time domain bundling window according to an embodiment of the present invention.

As shown in fig. 21, if "3" is configured as the value of N _slot of the terminal and the value of k is equal to "N-5" according to the above-described second information, slots starting from slot N-5 may be bundled to configure bundling windows, each of which includes 3 slots. For example, slot n-5, slot n-4, and slot n-3 are included in one bundling window (bundling window #A), and slot n-2, slot n-1, and slot n are included in another bundling window (bundling window #B). The terminal may select a PDSCH candidate latest in time sequence from among PDSCH candidates of the bundling window as a representative PDSCH (representative SLIV). For example, 4 PDSCH candidates indexed 3 according to the K1 value 2 and TDRA may be scheduled on slot n-5, slot n-4, slot n-3, and slot n-2. Of which the first 3 PDSCH candidates (PDSCH candidates scheduled on slots n-5, n-4, and n-3) belong to bundling window #a. Accordingly, the terminal may select a PDSCH candidate of slot n-3, which is the latest PDSCH candidate in time series, from among the PDSCH candidates as the representative PDSCH (representative SLIV). Then, 1 PDSCH candidate (PDSCH candidate scheduled on slot n-2) belongs to the bundling window #b. Accordingly, the terminal may select a PDSCH candidate of slot n-2, which is the latest PDSCH candidate in time series, from among the PDSCH candidates as the representative PDSCH (representative SLIV). A representative PDSCH (representative SLIV) selected in the above manner is shown in fig. 20.

In the following description, the selected PDSCH (SLIV corresponding thereto) is referred to as a representative PDSCH (or representative SLIV). A representative PDSCH (or representative SLIV) is determined for each group. The terminal may generate a type-1 HARQ-ACK CB based on the representative SLIV as follows.

1) Step 1: a set of indicated K1 values is named k1_set. The terminal may determine an index of a slot on which the representative PDSCH candidate (representative SLIV candidate) is received based on the k1_set and TDRA table. A set of indices is called K slot.

3) Step 3: the set of representative PDSCH candidates (representative SLIV candidates) that may be received on slot n-k1_max is referred to as R. When the symbols of the representative PDSCH candidates (representative SLIV candidates) included in the set R overlap with the symbols configured as uplink in the semi-static UL/DL configuration, the representative PDSCH candidates (representative SLIV candidates) are excluded from the set R.

Representative PDSCH candidates (representative SLIV candidates) included in the set R may be obtained as follows. A K1 value may be selected from k1_set. The selected value of K1 is K1_a. The terminal may determine a representative PDSCH candidate (representative SLIV candidate) on slot n-k1_max based on the k1_a value and TDRA table.

4) Step 4: the terminal performs the following steps a and B on the representative PDSCH candidates (representative SLIV candidates) included in R.

A) The new HARQ-ACK opportunity is assigned to the representative PDSCH candidate (representative SLIV candidate) with the top most last symbol among the representative PDSCH candidates (representative SLIV candidates) of set R. Then, if the set R includes a representative PDSCH candidate (representative SLIV candidate) with at least one symbol overlapping with the representative PDSCH candidate (representative SLIV candidate) with the foremost last symbol, the same HARQ-ACK opportunity is allocated to the representative PDSCH candidate (SLIV candidate representative). The representative PDSCH candidates (representative SLIV candidates) to which HARQ-ACK opportunities are allocated (representative PDSCH candidates (representative SLIV candidates) and representative PDSCH candidates (representative SLIV candidates) having the first and last symbols) are excluded from the set R, and at least one symbol thereof overlaps with the representative PDSCH candidates (representative SLIV candidates).

B) Step 4-a is repeated until set R becomes an empty set.

5) Step 5: the steps 2/3/4 are repeated until the K1_slot becomes an empty set.

6) Step 6: the terminal may assign B HARQ-ACK bits to the representative PDSCH candidates (representative SLIV candidates) assigned the same HARQ-ACK occasion). B is the maximum value of the number of PDSCH included in the group including each representative PDSCH candidate (representative SLIV candidate) to which the same HARQ-ACK occasion is allocated.

Fig. 22 is a diagram illustrating HARQ-ACK occasions according to a time domain bundling window according to an embodiment of the present invention.

Referring to fig. 22, in the above-described embodiment, a representative PDSCH candidate (representative SLIV candidate) may be determined according to fig. 21.

1) Step 1: terminals are assigned 1 and 2 as the value of K1 and thus k1_set is equal to 1 and 2 (k1_set=1, 2). If the terminal is configured with a K1 value of 2, then the representative PDSCH candidate (representative SLIV candidate) is located in slot n-3 and slot n-2. Thus, the K1 values of the slots are 3 and 2. These two values may be included in k1_slot. If the K1 value configured for the terminal is 1, then the representative PDSCH candidate (representative SLIV candidate) is located in slot n-3 and slot n-1. Thus, the K1 values of the slots are 3 and 1. These two values may be included in k1_slot. Thus, k1_slot includes 1,2, 3.

2) Step 2: k1_max=3, and the maximum value is selected among k1_slots. The K1 value is excluded from k_slot.

3) Step 3: a set of representative PDSCH candidates (representative SLIV candidates) that may be received on slot n-k1_max=n-3 is referred to as R. When the symbols of the representative PDSCH candidates (representative SLIV candidates) included in the set R overlap with the symbols configured as uplink in the semi-static UL/DL configuration, the representative PDSCH candidates (representative SLIV candidates) are excluded from the set R. Here, it is assumed that all symbols are downlink symbols.

Representative PDSCH candidates (representative SLIV candidates) included in the set R on the slot n-3 are (s=0, l=14), (s=0, l=7) and (s=7, l=7).

A) HARQ-ACK occasion 0 is allocated (s=0, l=7), which is a representative PDSCH candidate (representative SLIV candidate) having the most front last symbol among representative PDSCH candidates of the set R. Then, the same HARQ-ACK opportunity is allocated to the representative PDSCH candidate (representative SLIV candidate) (s=0, l=14), at least one symbol of which overlaps with the representative PDSCH candidate (representative SLIV candidate) having the foremost last symbol in the set R (s=0, l=7). (s=0, l=7) and (s=0, l=14) as representative PDSCH candidates (representative SLIV candidates) to which HARQ-ACK opportunities are allocated are excluded from the set R. Thus, the set R is equal to (s=7, l=7).

B) Step 4-a is repeated until set R becomes an empty set.

5) Set R is not an empty set, so step 4-A is repeated again. According to step 4-a, HARQ-ACK occasion 1 is allocated to a representative PDSCH candidate (representative SLIV candidate) (s=7, l=7) and set R becomes an empty set. Thus, step 4 ends.

5) Step 5: the steps 2/3/4 are repeated until the K1_slot becomes an empty set.

K1_slot=2, 1 and is therefore not an empty set. K1_slot is not an empty set, so step 2/3/4 is repeated again.

HARQ-ACK occasion 0: representative PDSCH candidates for slot n-3 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 1: representative PDSCH candidate of slot n-3 (s=7, l=7)

HARQ-ACK occasion 2: representative PDSCH candidates for slot n-2 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 3: representative PDSCH candidate of slot n-2 (s=7, l=7)

HARQ-ACK occasion 4: representative PDSCH candidates for slot n-1 (s=0, l=7) and (s=0, l=14)

HARQ-ACK occasion 5: representative PDSCH candidate of slot n-1 (s=7, l=7)

Thus, a type-1 HARQ-ACK codebook may be configured by 6 HARQ-ACK occasions.

6) Step 6: the number of HARQ-ACK bits that the terminal can obtain per HARQ-ACK occasion is as follows.

The representative PDSCH candidates included in HARQ-ACK occasion 0 are (s=0, l=7) and (s=0, l=14), and the TDRA indexes to which the representative PDSCH candidates belong in the bundling window are 0, 1, 3, 4, 6,7,8, and 9 when K1 is equal to 2, and are 3 and 4 when K1 is equal to 1. When K1 is equal to 2 and TDRA index is 3, there are up to 3 PDSCH candidates in the bundling window, and thus HARQ-ACK occasion 0 includes 3 HARQ-ACK bits. Similarly, HARQ-ACK occasion 1 may include 3 HARQ-ACK bits, HARQ-ACK occasion 2 may include 1 HARQ-ACK bit, HARQ-ACK occasion 3 may include 1 HARQ-ACK bit, HARQ-ACK occasion 4 may include 2 HARQ-ACK bits, and HARQ-ACK occasion 5 may include 2 HARQ-ACK bits.

Thus, the type-1 HARQ-ACK codebook may include a total of 12 HARQ-ACK bits.

Type 2 HARQ-ACK codebook

The terminal may be configured with a type 2HARQ-ACK codebook.

The type 2HARQ-ACK codebook may be configured by 2 sub-codebooks.

The first sub-codebook includes HARQ-ACK bits of a PDSCH corresponding to a Transport Block (TB) based transmission. If each PDSCH corresponding to the TB-based transmission is configured to include 1TB, each PDSCH generates 1 HARQ-ACK bit, and each PDSCH is configured to include 2 TBs in at least one cell, each PDSCH generates 2 HARQ-ACK bits. Thus, each DCI scheduling a TB-based transmission generates P HARQ-ACK bits. P is the number of maximum TBs included in PDSCH. For reference, if the number of TBs scheduled by DCI is less than P, as many HARQ-ACK bits as the insufficient number are configured as NACKs.

The second sub-codebook includes HARQ-ACK bits of PDSCH corresponding to Code Block Group (CBG) based transmissions. PDSCH corresponding to CBG-based transmission in cell c may be configured for a terminal to include N _CBG,c CBGs per TB. For all cells configured with CBG based transmissions, the maximum value of # (TB of cell c) NCBG, c is denoted N _CBG,max. The terminal generates N _CBG,max HARQ-ACK bits for each DCI scheduling a CBG-based transmission. For reference, if the number of CBGs scheduled by DCI is less than N _CBG,max, as many HARQ-ACK bits as the insufficient number are configured as NACKs.

The problem to be solved by the present invention is to determine one of a first sub-codebook and a second sub-codebook through which transmission is performed when one piece of DCI schedules a plurality of PDSCH.

As a first method of the present invention, when a plurality of PDSCHs are scheduled by one DCI (multi-PDSCH scheduling), a terminal always transmits HARQ-ACKs of the PDSCH by a second sub-codebook. The second sub-codebook may be modified as follows.

The second sub-codebook includes HARQ-ACK bits of PDSCH corresponding to Code Block Group (CBG) based transmission and HARQ-ACK bits of multiple PDSCH when multiple PDSCH are scheduled by DCI. PDSCH corresponding to CBG-based transmission in cell c may be configured for a terminal to include N _CBG,c CBGs per TB. For all cells configured with CBG based transmissions, the maximum value of # (TB of cell c) NCBG, c is denoted N _CBG,max. When a plurality of PDSCHs are scheduled for a terminal through DCI, the maximum value of the number of PDSCHs scheduled by one TDRA index is N _{multi-PDSCH,max}.

The terminal generates max (N _CBG,max,N_{multi-PDSCH,max}) HARQ-ACK bits for each DCI indicating CBG-based transmission. The terminal generates max (N _CBG,max,N_{multi-PDSCH,max}) HARQ-ACK bits for each DCI indicating the multiple PDSCH scheduling. If the number of CBGs scheduled by the DCI is less than max (N _CBG,max,N_{multi-PDSCH,max}), as many HARQ-ACK bits as the insufficient number are configured as NACKs. If the number of PDSCHs scheduled by DCI indicating multi-PDSCH scheduling is less than max (N _CBG,max,N_{multi-PDSCH,max}), as many HARQ-ACK bits as the insufficient number are configured as NACK.

As a second method of the present invention, when one DCI schedules a plurality of PDSCH, a terminal selects a first sub-codebook or a second sub-codebook according to the number of PDSCH to transmit HARQ-ACK of PDSCH. The first sub-codebook and the second sub-codebook may be modified as follows.

The first sub-codebook includes HARQ-ACK bits of PDSCH corresponding to transmission based on a Transport Block (TB), and if the number of PDSCH is equal to or less than X when PDSCH is scheduled by one DCI, the first sub-codebook includes HARQ-ACK bits of multiple PDSCH. It is assumed that each PDSCH corresponding to a TB-based transmission is configured to include P TBs. P is the number of maximum TBs included in PDSCH. Thus, max { P, X } HARQ-ACK bits are generated per DCI in scheduling a TB-based transmission. For reference, if the number of TBs scheduled by DCI is less than max { P, X }, as many HARQ-ACK bits as the insufficient number are configured as NACK. Max { P, X } HARQ-ACK bits are generated at each DCI scheduling a TB-based transmission. For reference, DCI indicating multi-PDSCH scheduling includes X or less PDSCHs. If the number of PDSCHs scheduled by DCI indicating multi-PDSCH scheduling is less than max { P, X }, as many HARQ-ACK bits as the insufficient number are configured as NACKs.

The second sub-codebook includes: HARQ-ACK bits of PDSCH corresponding to Code Block Group (CBG) based transmissions; and HARQ-ACK bits of the plurality of PDSCHs if the number of the plurality of PDSCHs exceeds X when the PDSCHs are scheduled through the DCI. PDSCH corresponding to CBG-based transmission in cell c may be configured for a terminal to include N _CBG,c CBGs per TB. For all cells configured with CBG based transmissions, the maximum value of # (TB of cell c) NCBG, c is denoted N _CBG,max. When DCI schedules multiple PDSCH for a terminal, the maximum value of the number of multiple PDSCH scheduled by one TDRA index is N _{multi-PDSCH,ma} x. For reference, N _{multi-PDSCH,max} is a value greater than X.

The terminal generates max (N _CBG,max,N_{multi-PDSCH,max}) HARQ-ACK bits for each DCI indicating CBG-based transmission. The terminal generates max (N _CBGmax,N_{multi-PDSCHmax}) HARQ-ACK bits for each DCI indicating the multiple PDSCH scheduling. If the number of CBGs for DCI scheduling is less than max (N _CBG,max,N_{multi-PDSCH,max}), as many HARQ-ACK bits as there are insufficient numbers are configured as NACK. If the number of PDSCH scheduled by DCI indicating multi-PDSCH scheduling is less than max (N _CBG,max,N_{multi-PDSCH,max}), as many HARQ-ACK bits as the insufficient number are configured as NACK.

In the above embodiment, x=p may be determined as needed. That is, if multiple PDSCH scheduling of DCI schedules P or less PDSCHs, HARQ-ACKs of the PDSCH are included in the first sub-codebook, and if multiple PDSCH scheduling of DCI schedules more than X PDSCHs, HARQ-ACKs of the PDSCH are included in the second sub-codebook.

When the type 2HARQ-ACK codebook and the time domain bundling are simultaneously configured, both methods may be modified as follows.

As a modified second method of the present invention, when a plurality of PDSCHs are scheduled by one piece of DCI, a terminal selects and transmits a first sub-codebook or a second sub-codebook according to the number of bundled HARQ-ACK bits corresponding to the DCI. The first sub-codebook and the second sub-codebook may be modified as follows.

The first sub-codebook includes: HARQ-ACK bits of PDSCH corresponding to Transport Block (TB) based transmissions; and bundling HARQ-ACK bits if bundling HARQ-ACKs corresponding to the DCI have X bits or less when a plurality of PDSCHs are scheduled by one piece of DCI. It is assumed that each PDSCH corresponding to a TB-based transmission is configured to include P TBs. P is the number of maximum TBs included in PDSCH. Thus, max { P, X } HARQ-ACK bits are generated for each DCI scheduling a TB-based transmission. For reference, if the number of TBs scheduled by DCI is less than max { P, X }, as many HARQ-ACK bits as the insufficient number are configured as NACKs. Max { P, X } bundled HARQ-ACK bits are generated for each DCI scheduling a TB-based transmission. For reference, DCI indicating multi-PDSCH scheduling corresponds to X or less bundled HARQ-ACK bits. If the number of bundled HARQ-ACK bits corresponding to DCI indicating multi-PDSCH scheduling is less than max { P, X }, as many bundled HARQ-ACK bits as the insufficient number are configured as NACK.

The second sub-codebook includes: HARQ-ACK bits of PDSCH corresponding to Code Block Group (CBG) based transmissions; and bundling HARQ-ACK bits if bundling HARQ-ACKs corresponding to the DCI exceeds X bits when the plurality of PDSCHs are scheduled by the DCI. PDSCH corresponding to CBG-based transmission in cell c may be configured for a terminal to include N _CBG,c CBGs per TB. For all cells configured with CBG based transmissions, the maximum value of # (TB of cell c) NCBG, c is denoted N _CBG,max. When the DCI schedules multiple PDSCH for the terminal, the maximum value of the number of bundled HARQ-ACK bits corresponding to one TDRA index is N _bundled,max. For reference, N _bundled,max is a value greater than X.

The terminal generates max (N _CBG,max,N_bundled,max) HARQ-ACK bits for each DCI indicating CBG-based transmission. The terminal generates max (N _CBG,max,N_bundled,max) HARQ-ACK bits for each DCI indicating the multiple PDSCH scheduling. If the number of CBGs scheduled by the DCI is less than max (N _CBG,max,N_bundled,max), as many HARQ-ACK bits as the insufficient number are configured as NACKs. If the number of bundled HARQ-ACK bits corresponding to DCI indicating multi-PDSCH scheduling is less than max (N _CBG,max,N_bundled,max), as many bundled HARQ-ACK bits as the insufficient number are configured as NACK.

For example, assume that a terminal always generates 1 bundled HARQ-ACK bit for DCI indicating multi-PDSCH scheduling. In this case, the terminal always includes bundled HARQ-ACK bits as a first sub-codebook.

Method for allocating HARQ process numbers when multiple PDSCHs or multiple PUSCHs are scheduled

As described above, in NR, a plurality of PDSCH or a plurality of PUSCH may be scheduled on a plurality of slots. Multiple PDSCH or multiple PUSCH may be scheduled by one DCI, and HARQ-ACKs for the scheduled multiple PDSCH may be transmitted on one or more slots through the PUCCH.

In this case, it becomes a problem to assign HARQ process numbers (or HARQ process IDs) to the scheduled plurality of PDSCH or plurality of PUSCH. In particular, in the case where symbols of a plurality of slots in which a plurality of PDSCH or a plurality of PUSCH are scheduled overlap with symbols configured for different purposes through higher layer signaling (e.g., TDD-UL-DL-ConfigurationCommon or TDD-UL-DL-ConfigurationDedicated as RRC configuration information), configuration of HARQ process numbers corresponding to each PDSCH or each PUSCH in which a plurality of PDSCH or a plurality of PUSCH are configured may be problematic.

Hereinafter, the problem to be solved in the present invention relates to a method of allocating a HARQ Process Number (HPN) for a PDSCH or PUSCH scheduled on a plurality of slots and thus individually scheduled on each slot when the PDSCH or PUSCH is scheduled as a multi-slot schedule by one piece of DCI.

When PDSCH or PUSCH is scheduled as multislot scheduling by one DCI, PDSCH or PUSCH scheduled on symbols, in particular, flexible symbols may collide with different DL or UL slots and symbols, and in addition, ambiguity for HPN between terminal and base station may occur when terminal configured to monitor DCI2_0 (i.e., SFI) has received it or has failed to receive it. Accordingly, a method of solving this problem is provided.

Specifically, in the case where a plurality of PDSCH or a plurality of PUSCH is scheduled on a plurality of slots by one piece of DCI, the DCI may indicate the HARQ process number of the first PDSCH among the plurality of PDSCH or the first PUSCH among the PUSCH. Thereafter, the HARQ process number may be increased by 1 according to the scheduling order of the PDSCH or PUSCH.

That is, the HARQ process number of the PDSCH after the first PDSCH or the PUSCH after the first PUSCH is increased by "1". The symbol of the slot in which the first PDSCH or the first PUSCH is transmitted does not overlap with the UL symbol indicated by the RRC configuration information.

However, in the case where a symbol included in each slot in which a plurality of PDSCH or a plurality of PUSCH is scheduled overlaps with a UL symbol or a DL symbol indicated by RRC configuration information, the PDSCH or PUSCH is not transmitted on the corresponding slot, and the HARQ process number of the PDSCH or PUSCH of the slot is not increased. Thereafter, if the PDSCH scheduled on the next slot is valid (valid PDSCH) or the PUSCH scheduled on the next slot is valid (valid PUSCH), the HARQ process number is increased.

Specifically, in case of scheduling a plurality of PDSCHs by one DCI, if a symbol of a slot transmitting a first PDSCH is not overlapped with a symbol configured as a UL symbol by RRC configuration information, a HARQ process number indicated by the DCI is applied to the first PDSCH. After the first PDSCH, if the symbol of the slot in which the next PDSCH is transmitted does not overlap with the UL symbol indicated by the RRC configuration information or overlaps with the DL symbol indicated by the RRC configuration information, a valid PDSCH may be received and the HARQ process number is incremented by "1". However, if the symbol of the slot in which the next PDSCH is scheduled overlaps with the UL symbol indicated by the RRC configuration information, the next PDSCH is not received and the HARQ process number is not increased.

If the symbols of the slots on which the plurality of PDSCH are scheduled overlap with the flexible symbols indicated by the RRC configuration information, the HARQ process number may be increased regardless of whether the PDSCH is received. That is, even if the flexible symbol is indicated as UL or flexible by the SFI of the DCI format 2_0 and thus the PDSCH is not received, the HARQ process number may be increased. That is, the format of the symbol indicated by the SFI may be independent of whether the HARQ process number is increased. This can solve the problem of whether to increase the HARQ process number when ambiguity occurs between the terminal and the base station because no SFI is detected.

If the UL symbols indicated by the RRC configuration information and the symbols of the slots overlap each other and thus reception of the PDSCH is not performed and the HARQ process number is not increased, the HARQ process number is increased by "1" when the PDSCH scheduled on the slot subsequent to the slot in which the PDSCH was not received is valid.

In the case of scheduling a plurality of PUSCHs by one piece of DCI, if a symbol of a slot in which a first PUSCH is transmitted does not overlap with a symbol configured as a DL symbol by RRC configuration information, a HARQ process number indicated by the DCI is applied to the first PUSCH. After the first PUSCH, if the symbol of the slot in which the next PUSCH is transmitted does not overlap with the DL symbol indicated by the RRC configuration information or overlaps with the UL symbol indicated by the RRC configuration information, a valid PUSCH may be transmitted and the HARQ process number is increased by "1". However, if the symbol of the slot in which the next PUSCH is scheduled overlaps with the DL symbol indicated by the RRC configuration information, the next PUSCH is not transmitted and the HARQ process number is not increased.

If the symbols of the slots on which the plurality of PUSCHs are scheduled overlap with the flexible symbols indicated by the RRC configuration information, the HARQ process number may be increased according to whether the reception of a specific signal (e.g., synchronization signal/PBCH block (SSB)) on the symbols is configured. If the reception of a specific signal is not configured on the symbol, the HARQ process number may be increased even if the symbol is indicated as DL or flexible by the SFI of DCI format 2_0 and thus PUSCH is not transmitted. That is, the format of the symbol indicated by the SFI may be independent of whether the HARQ process number is increased. Whether to configure the reception of a specific signal may be determined based on the SSB index provided as RRC configuration information by SSBPositioninburst. The SSB may be indicated (or configured) as whether or not the SSB is received through SSBPositioninburst as a higher layer parameter of RRC configuration information. That is, if the terminal receives the RRC configuration information, the terminal may determine whether to configure the SSB through SSBPositioninburst as a parameter included in the RRC configuration information. In the case where the transmission of the plurality of PUSCHs is scheduled and the symbol of the slot on which the PUSCH of the plurality of PUSCHs is scheduled overlaps with the flexible symbol indicated by the RRC configuration information, if a specific signal is configured to be received on the symbol, the transmission of the PUSCH is not performed and the HARQ process number is not increased.

However, in the case where the transmission of the plurality of PUSCHs is scheduled and the symbol of the slot scheduling the PUSCH of the plurality of PUSCHs overlaps with the flexible symbol indicated by the RRC configuration information, if the reception of the specific signal on the symbol is not configured, the HARQ process number increases regardless of whether the PUSCH is transmitted. If the reception of a specific signal is not configured on the symbol, the HARQ process number may be increased even if the symbol is indicated as DL or flexible by the SFI of DCI format 2_0 and thus PUSCH is not transmitted. This can solve the problem as to whether or not to increase the HARQ process number when ambiguity occurs between the terminal and the base station because the SFI is not detected.

If DL symbols indicated by RRC configuration information and symbols of slots overlap each other and thus transmission of PUSCH is not performed and HARQ process number is not increased, HARQ process number is increased by "1" when PUSCH scheduled on a subsequent slot is valid.

As the flexible symbol configured by the RRC configuration information, a symbol that is not indicated as a DL symbol or UL symbol by the RRC configuration information may be indicated. That is, if the RRC configuration information does not indicate a symbol as a DL symbol or a UL symbol, the symbol may be identified as being implicitly indicated as a flexible symbol.

In other words, in case of scheduling a plurality of PDSCHs (or a plurality of PUSCHs) for a terminal, the terminal may expect the base station to indicate an effective PDSCH (or PUSCH) resource for a first scheduled PDSCH (or a first scheduled PUSCH), apply an HPN indicated by DCI to the effective PDSCH (or PUSCH), and increase an HPN for a subsequent PDSCH among the plurality of PDSCHs by 1.

DL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not UL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PDSCH in the above description, however, if PDSCH scheduled on flexible symbols collides with UL, the corresponding HPN is not skipped (i.e., HPN plus 1) and the HPN of the subsequent PDSCH is increased by 1.

UL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not DL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PUSCH in the above description, however, if the PUSCH scheduled on the flexible symbol collides with DL, the corresponding HPN is not skipped (i.e., HPN increases by 1) and the HPN of the subsequent PUSCH increases by 1.

As another embodiment of the present invention, in case of scheduling a plurality of PDSCH (or a plurality of PUSCH) for a terminal, resources of a pre-configured channel (e.g., SPS-PDSCH or CG-PUSCH) may be regarded as effective PDSCH resources for allocating HPNs to a first scheduled PDSCH (or a first scheduled PUCH). However, the terminal may skip HPNs of pre-configured channels (e.g., pre-configured SPS-PDSCH or CG-PUSCH) and assign the HPNs to multiple PDSCH (or PUSCH) while sequentially increasing the HPNs by 1.

In case of scheduling multiple PDSCH (or multiple PUSCH) for the terminal, the resources of the pre-configured channel (e.g. SPS-PDSCH or CG-PUSCH) may be regarded as valid PDSCH (or PUSCH) resources for allocating HPNs to the first scheduled PDSCH (or first scheduled PUSCH). If the resources scheduled by the base station to be dynamic overlap with a pre-configured channel (e.g., a pre-configured SPS-PDSCH or CG-PUSCH), the terminal may expect the base station to disregard the HPN of the pre-configured SPS-PDSCH or CG-PUSCH, may not skip the HPN of the pre-configured SPS-PDSCH or CG-PUSCH, and assign the HPN to multiple PDSCH (or multiple PUSCH) while sequentially increasing the HPN by 1.

As another embodiment of the present invention, in case of scheduling a plurality of PDSCH (or a plurality of PUSCH) for a terminal, the terminal may expect the base station to indicate valid PDSCH (or PUSCH) resources for a first scheduled PDSCH (or a first scheduled PUSCH), apply the HPN indicated by DCI to the valid PDSCH (or PUSCH), and add 1 to the HPN for a subsequent PDSCH among the plurality of PDSCH.

DL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not UL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PDSCH in the above description, however, if PDSCH scheduled on flexible symbols collides with SSB transmitted by the base station, HPN is skipped plus 1 (i.e., HPN is not plus 1), and HPN of subsequent PDSCH is increased by 1. The terminal may not desire to schedule multiple PDSCH on flexible symbols configured to receive SSB transmissions and for SSB reception corresponding to SSB transmissions from the base station, the terminal may assume that one or more SSBs with candidate SSB indices corresponding to SSB indices provided by SSB PositionsInBurst configured by the base station may be transmitted and may not desire to schedule multiple PDSCH on flexible symbols configured to receive SSB transmissions.

UL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not DL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PUSCH in the above description, and however, if the PUSCH scheduled on a flexible symbol collides with SSB, the HPN increase of 1 is skipped (i.e., the HPN is not increased by 1) and the HPN of the subsequent PUSCH increases by 1. The terminal may not desire to schedule multiple PUSCHs on flexible symbols configured to receive SSBs, and for SSB reception corresponding to SSB transmissions from the base station, the terminal may assume that one or more SSBs with candidate SSB indices corresponding to SSB indices provided by SSB-PositionsInBurst configured by the base station may be transmitted, and may not desire to schedule multiple PUSCHs on flexible symbols configured to receive SSB transmissions. In the case where a plurality of PUSCHs are scheduled for a terminal on flexible symbols that can be assumed to be received by an SSB, if a first scheduled PUSCH among the plurality of PUSCHs or a scheduled PUSCH subsequent to the first scheduled PUSCH among the plurality of PUSCHs is scheduled, when the PUSCH scheduled for the terminal collides with the SSB, the HPN is skipped by 1 (i.e., the HPN is not increased by 1), and the HPN of the subsequent PUSCHs is increased by 1.

DL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not UL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PDSCH in the above description, and however, if PDSCH scheduled on flexible symbols collides with group common signaling (e.g., UL cancel indication, slot Format Indication (SFI), or rate matching pattern indication) transmitted by the base station, HPN increase of 1 (i.e., HPN increase of 1) is not skipped and HPN of subsequent PDSCH increases by 1. As described above, in the case of dynamic indication, ambiguity may occur between the terminal and the base station when the terminal receives it or fails to receive it. Thus, the terminal may operate based on the schedule indicated by the base station to resolve the ambiguity. However, with respect to a resource configuration that enables the terminal and the base station to be understood in conformity with RRC signaling, there is no ambiguous space between the terminal and the base station, thus allowing the terminal to perform an operation corresponding to the RRC configuration without modification.

UL/flexible symbols configured by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated and not DL slots/symbols are all considered as valid PDSCH (or PUSCH) resources in the case of PUSCH in the above description, and however, if the PUSCH scheduled on a flexible symbol collides with group common signaling (e.g., UL cancel indication, slot Format Indication (SFI) or rate matching mode indication) sent by the base station, the HPN increase of 1 is not skipped (i.e., the HPN increases by 1), and the HPN of the subsequent PUSCH increases by 1. As described above, in the case of dynamic indication, ambiguity may occur between the terminal and the base station when the terminal receives it or fails to receive it. Thus, the terminal may operate based on the schedule indicated by the base station to resolve the ambiguity. However, with respect to a resource configuration that enables the terminal and the base station to be understood in conformity with RRC signaling, there is no ambiguous space between the terminal and the base station and thus the terminal is allowed to perform operations corresponding to the RRC configuration without modification.

Referring to fig. 23, in case of scheduling transmission of a plurality of PUSCHs through one DCI, a terminal may configure HARQ process numbers for the plurality of PUSCHs.

Specifically, the terminal receives Radio Resource Control (RRC) configuration information related to the configuration of the slot from the base station (operation S23010). The RRC configuration information may include at least one of TDD-UL-DL-ConfigurationDedicated or TDD-UL-DLConfigurationCommon.

Thereafter, the terminal receives a Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) scheduled for a plurality of Physical Uplink Shared Channels (PUSCHs) of the terminal from the base station (operation S23030).

The DCI may indicate a hybrid automatic repeat request (HARQ) process number of a first PUSCH among the plurality of PUSCHs, and may increase the HARQ process number of the PUSCH included in the plurality of PUSCHs as compared to the HARQ process number of a previous PUSCH of the PUSCH according to whether a symbol of a slot of a scheduled PUSCH overlaps with a symbol indicated as downlink or flexible by RRC configuration information.

Specifically, as described above, in the case where a plurality of PUSCHs are scheduled by one piece of DCI, if a symbol of a slot on which a first PUSCH is transmitted does not overlap with a symbol configured as a DL symbol by RRC configuration information, the HARQ process number indicated by the DCI is applied to the first PUSCH. After the first PUSCH, if the symbol of the slot in which the next PUSCH is scheduled does not overlap with the DL symbol indicated by the RRC configuration information or overlaps with the UL symbol indicated by the RRC configuration information, a valid PUSCH may be transmitted and the HARQ process number is increased by "1". However, if the symbol of the slot in which the next PUSCH is scheduled overlaps with the DL symbol indicated by the RRC configuration information, the next PUSCH is not transmitted and the HARQ process number is not increased.

If the symbols of the slots on which the plurality of PUSCHs are scheduled overlap with the flexible symbols indicated by the RRC configuration information, the HARQ process number may be increased according to whether the reception of a specific signal (e.g., synchronization signal/PBCH block (SSB)) on the symbols is configured. If the reception of a specific signal is not configured on the symbol, the HARQ process number may be increased even if the symbol is indicated as DL or flexible by the SFI of DCI format 2_0 and thus PUSCH is not transmitted. That is, the format of the symbol indicated by the SFI may be independent of whether the HARQ process number is increased. Whether to configure the reception of a specific signal may be determined based on the SSB index provided as RRC configuration information by SSBPositioninburst. The SSB may be indicated (or configured) as whether or not the SSB is received through SSBPositioninburst as a higher layer parameter of RRC configuration information. That is, if the terminal receives the RRC configuration information, the terminal may determine whether the SSB is configured through SSBPositioninburst as a parameter included in the RRC configuration information.

That is, in the case where the transmission of the plurality of PUSCHs is scheduled and the symbol of the slot of the PUSCH among the plurality of PUSCHs overlaps with the flexible symbol indicated by the RRC configuration information, if the reception of the characteristic signal on the symbol is configured, the transmission of the PUSCH is not performed, and the HARQ process number is not increased.

However, in the case where the transmission of the plurality of PUSCHs is scheduled and the symbol of the slot of the PUSCH among the plurality of PUSCHs overlaps with the flexible symbol indicated by the RRC configuration information, if the reception of the characteristic signal not configured on the symbol, the HARQ process number increases regardless of whether the PUSCH is transmitted. If the reception of a specific signal is not configured on the symbol, the HARQ process number may be increased even if the symbol is indicated as DL or flexible by the SFI of DCI format 2_0 and thus PUSCH is not transmitted. This can solve the problem as to whether or not to increase the HARQ process number when ambiguity occurs between the terminal and the base station because the SFI is not detected.

The above description of the present invention is for illustration and it will be understood by those skilled in the art that the present invention may be easily modified into other detailed forms without changing the technical idea or essential features thereof. Accordingly, it should be understood that the above-described embodiments are intended to be illustrative in all respects, rather than restrictive. For example, each element described as a single type may be implemented as distributed, and similarly, elements described as distributed may also be implemented in an associated form.

The scope of the invention is indicated by the appended claims rather than by the foregoing detailed description, and all changes and modifications that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Claims

1. A terminal of a wireless communication system, the terminal comprising:

A communication module; and

The processor may be configured to perform the steps of,

Wherein the processor is configured to:

receiving Radio Resource Control (RRC) configuration information related to configuration of a slot from a base station; and

Receiving a Physical Downlink Control Channel (PDCCH) from the base station, the Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) of a plurality of Physical Uplink Shared Channels (PUSCHs) scheduled for the terminal,

Wherein the DCI indicates a hybrid automatic repeat request (HARQ) process number of a first PUSCH among the plurality of PUSCHs, and

Wherein HARQ process numbers of PUSCHs included in the plurality of PUSCHs are increased compared to HARQ process numbers of previous PUSCHs of the PUSCH according to whether symbols of a slot in which the PUSCH is scheduled overlap with symbols indicated as downlink or flexible by the RRC configuration information.

2. The terminal according to claim 1,

Wherein when the symbol of the slot in which the PUSCH is scheduled is indicated as an uplink symbol by the RRC configuration information, the HARQ process number of the PUSCH is increased by "1" compared to the HARQ process number of the previous PUSCH.

3. The terminal according to claim 1,

Wherein the PUSCH is not transmitted on the slot when the symbol of the slot in which the PUSCH is scheduled overlaps with a downlink symbol indicated by the RRC configuration information.

4. A terminal according to claim 3,

Wherein the HARQ process number of the PUSCH is not increased compared to the HARQ process number of the previous PUSCH.

5. A terminal according to claim 3,

Wherein when the symbol of a slot where a next PUSCH of the PUSCHs is scheduled is indicated as an uplink symbol by the RRC configuration information, the HARQ process number of the next PUSCH is increased by "1" compared to the HARQ process number of a previous PUSCH.

6. The terminal according to claim 1,

Wherein when the symbol of the slot in which the PUSCH is scheduled overlaps with a flexible symbol indicated by the RRC configuration information, the HARQ process number of the PUSCH is increased by "1" compared to the HARQ process number of the previous PUSCH according to whether a specific signal is configured on the flexible symbol.

7. The terminal according to claim 6,

Wherein the specific signal is a synchronization signal/PBCH block (SSB) indicated by SSBpositioninburst, and the SSBpositioninburst is a higher layer parameter of RRC configuration information.

8. The terminal according to claim 6,

Wherein when the specific signal is not configured on the flexible symbol, the HARQ process number of the PUSCH is increased by "1" compared to the HARQ process number of the previous PUSCH.

9. The terminal according to claim 8,

Wherein the HARQ process number of the PUSCH is increased by "1" compared to the HARQ process number of the previous PUSCH, whether the symbol of the slot in which the PUSCH is scheduled is indicated as uplink, downlink, or flexible by a Slot Format Indicator (SFI).

10. The terminal according to claim 1,

Wherein the symbol of the slot in which the first PUSCH is transmitted is not overlapped with the symbol indicated as downlink by the RRC configuration information.

11. A terminal of a wireless communication system, the terminal comprising:

A communication module; and

The processor may be configured to perform the steps of,

Wherein the processor is configured to:

Receiving a Physical Downlink Control Channel (PDCCH) from the base station, the Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) of a plurality of physical downlink shared channels (PUSCHs) scheduled for the terminal,

The DCI indicates a hybrid automatic repeat request (HARQ) process number of a first PDSCH among the plurality of PDSCHs, an

According to whether or not a symbol of a slot in which the PDSCH is scheduled overlaps with a symbol indicated as uplink or flexible by the RRC configuration information, HARQ process numbers of PDSCH included in the plurality of PDSCH are increased compared to HARQ process numbers of previous PDSCH of the PDSCH.

12. The terminal according to claim 11,

Wherein when the symbol of the slot in which the PDSCH is scheduled is indicated as a downlink symbol by the RRC configuration information, the HARQ process number of the PDSCH is increased by "1" compared to the HARQ process number of the previous PDSCH.

13. The terminal according to claim 11,

Wherein the PDSCH is not received on the slot when the symbol of the slot in which the PDSCH is scheduled overlaps with an uplink symbol indicated by the RRC configuration information.

14. The terminal according to claim 13,

Wherein the HARQ process number of the PDSCH is not increased compared to the HARQ process number of the previous PDSCH.

15. The terminal according to claim 13,

Wherein when the symbol of a slot in which a next PDSCH of the PDSCH among the plurality of PDSCH is scheduled is indicated as a downlink symbol by RRC configuration information, the HARQ process number of the next PDSCH is increased by "1" compared to the HARQ process number of the previous PDSCH.

16. The terminal according to claim 11,

Wherein when the symbol of the slot in which the PDSCH is scheduled overlaps with a flexible symbol indicated by the RRC configuration information, the HARQ process number of the PDSCH is increased by "1" compared to the HARQ process number of the previous PDSCH.

17. The terminal according to claim 16,

Wherein the HARQ process number of the PDSCH is increased by "1" compared to the HARQ process number of the previous PDSCH, whether or not the symbol of the slot in which the PDSCH is scheduled is indicated as uplink, downlink, or flexible by a Slot Format Indicator (SFI).

18. The terminal according to claim 11,

Wherein a symbol of a slot in which the first PDSCH is transmitted does not overlap with a symbol indicated as an uplink by the RRC configuration information.

19. A method of transmitting a Physical Uplink Shared Channel (PUSCH) by a terminal in a wireless communication system, the method comprising:

A Physical Downlink Control Channel (PDCCH) including Downlink Control Information (DCI) scheduled for a plurality of PUSCHs of the terminal is received from the base station,

According to whether the symbol of the slot in which the PUSCH is scheduled overlaps with the symbol indicated as downlink or flexible by the RRC configuration information, the HARQ process number of the PUSCH included in the plurality of PUSCHs is increased compared to the HARQ process number of the previous PUSCH of the PUSCH.