Method, apparatus and system for transmitting HARQ-ACK codebook in wireless communication system

Abstract

To provide a method and apparatus for efficiently transmitting and receiving signals in a wireless communication system.SOLUTION: The present invention relates to a wireless communication system and, more specifically, to a method and an apparatus therefor, the method comprising the steps of: receiving a PDCCH for multi-slot scheduling; determining a PDSCH candidate for each slot on the basis of information in the PDCCH; and transmitting a semi-static HARQ-ACK codebook on the basis of the determined PDSCH candidate of each slot.SELECTED DRAWING: Figure 20

Description

[Technical field]

[0001] The present invention relates to a wireless communication system, and more particularly to a method, apparatus and system for transmitting a HARQ-ACK codebook in a wireless communication system. [Background technology]

[0002] 3GPP (registered trademark, the same applies below) LTE(-A) defines uplink / downlink physical channels to transmit physical layer signals. For example, the Physical Uplink Shared Channel (PUSCH), which is a physical channel for transmitting data in the uplink, the Physical Uplink Control Channel (PUCCH), which transmits control signals, and the Physical Random Access Channel (PRACH) are defined, and the Physical Downlink Shared Channel (PDSCH), which transmits data in the downlink, the Physical Control Format Indicator Channel (PCFICH), the Physical Downlink Control Channel (PDCCH), and the Physical Hybrid ARQ Indicator Channel (PHICH), which transmit L1 / L2 control signals, are also defined.

[0003] Among the channels, the downlink control channel (PDCCH / EPDCCH) is a channel for a base station to transmit uplink / downlink scheduling allocation control information, uplink transmission power control information, and other control information to one or more terminals. Since the base station has a limited number of resources that can be used for the PDCCH that can be transmitted at one time, it is not possible to assign different resources to each terminal, and the resources should be shared to transmit control information to any terminal. For example, in 3GPP LTE(-A), four resource elements (REs) are bundled to create a resource element group (REG), nine control channel elements (CCEs) are created, and resources that can be sent by combining one or more CCEs are notified to the terminal, and many terminals share and use the CCEs. Here, the number of CCEs to be combined is called the CCE combining level, and the resource to which the CCE is assigned according to the possible CCE combining level is called a search space. There are a common search space defined for each base station and a terminal-specific or UE-specific search space defined for each terminal. The terminal performs decoding for all possible CCE combinations in the search space and determines whether the PDCCH corresponds to its own PDCCH based on the user equipment (UE) identifier included in the PDCCH. Therefore, such a terminal operation takes a long time to decode the PDCCH and consumes a lot of energy.

[0004] After the commercialization of the 4G communication system, efforts are being made to develop an improved 5G or pre-5G communication system to meet the increasing demand for wireless data traffic. For this reason, the 5G or pre-5G communication system is called a communication system beyond the 4G network (Beyond 4G Network) or a system beyond the LTE system (Post LTE). To achieve a high data transmission rate, the 5G communication system is being considered for implementation in the ultra-high frequency (mmWave) band (e.g., 60 GHz band). To mitigate the path loss of propagation in the ultra-high frequency band and increase the propagation distance, beamforming, massive MIMO, full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, and large scale antenna technologies are being discussed in the 5G communication system. In addition, to improve the system network, technologies being developed for the 5G communication system include advanced small cells, improved small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device to device communication (D2D), wireless backhaul, moving networks, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation.In addition, advanced coding modulation (ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding) as well as advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (non orthogonal multiple access), and SCMA (sparse code multiple access) are being developed for 5G systems.

[0005] Meanwhile, the Internet is a human-centered network where humans generate and consume information, and is evolving into the Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. The Internet of Everything (IoE) technology is also emerging, which combines big data processing technology through connection with cloud servers with IoT technology. To realize IoT, technological elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, technologies such as sensor networks for connecting objects, machine to machine (M2M), and machine type communication (MTC) are being researched. In the IoT environment, intelligent IT (internet technology) services are provided that collect and analyze data generated from connected objects and create new value in human life. IoT is applied to fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart home appliances, and advanced medical services through the fusion and integration of conventional IT technology and various industries.

[0006] Therefore, various attempts are being made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine, and MTC are being embodied by 5G communication technologies such as beamforming, MIMO, and array antennas. The application of cloud radio access network (cloud RAN) as the big data processing technology mentioned above can also be said to be an example of the fusion of 5G technology and IoT technology.

[0007] Generally, mobile communication systems have been developed to provide voice services while ensuring the activity of users. Generally, mobile communication systems have been developed to provide voice services while ensuring the activity of users. However, mobile communication systems have gradually expanded their service areas to include not only voice but also data services, and have now evolved to the point where they can provide high-speed data services. However, due to resource shortages in currently-provided mobile communication systems and users' demands for higher-speed services, there is a demand for more advanced mobile communication systems.

[0008] As mentioned above, future 5G technology will require lower latency data transmission with the emergence of new applications such as real-time control and tactile internet, and the required latency of 5G data is expected to drop to 1ms. 5G aims to provide data latency that is approximately 10 times lower than conventional latency. To solve this problem, 5G is expected to propose a communication system that uses mini-slots with a shorter TTI period (e.g., 0.2ms) than conventional slots (or subframes). Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a method and an apparatus for efficiently transmitting and receiving signals in a wireless communication system. Another object of the present invention is to provide a method and an apparatus for efficiently transmitting a HARQ-ACK codebook in a wireless communication system. Here, the wireless communication system may include a 3GPP-based wireless communication system, for example a 3GPP NR-based wireless communication system.

[0010] The invention is not limited to what has been specifically described herein. [Means for solving the problem]

[0011] According to one aspect of the present invention, a terminal for use in a wireless communication system includes a communication module; and a processor for controlling the communication module, the processor receiving a physical downlink control channel (PDCCH) having the following information:

[0012] - Index information indicating an entry in a time-domain resource allocation (TDRA) table for physical downlink shared channel (PDSCH) allocation; and

[0013] - K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 i} (i=1, 2, ...), where the timing information indicates slot n, for all K1 values ​​in the K1 set, slot n-K1 iand transmitting a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot, wherein at least one entry in the TDRA table is associated with a plurality of PDCCH-to-PDSCH slot timing K0 values, and a terminal is provided in which, when determining the PDSCH candidates, the K1 set is replaced by a union of the following K sets #i:

[0014] - K set #i: {K1 i +d1,K1 i +d2,...,K1 i +d N},

[0015] where d k (k=1,2,...,N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

[0016] According to another aspect of the present invention, there is provided a method for use by a terminal in a wireless communication system, comprising the steps of receiving a physical downlink control channel (PDCCH) having the following information:

[0017] - Index information indicating an entry in a time-domain resource allocation (TDRA) table for physical downlink shared channel (PDSCH) allocation; and

[0018] - K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 i} (i=1, 2, ...), where the timing information indicates slot n, for all K1 values ​​in the K1 set, slot n-K1 i and transmitting a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot, wherein based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values, when determining the PDSCH candidates, the K1 set is replaced with a union of the following K sets #i:

[0019] - K set #i: {K1 i +d1,K1 i +d2,...,K1 i +d N},

[0020] where d k (k=1,2,...,N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

[0021] According to yet another aspect of the present invention, there is provided a base station for use in a wireless communication system, the base station comprising: a communication module; and a processor for controlling the communication module, the processor transmitting a physical downlink control channel (PDCCH) having the following information:

[0022] - Index information indicating an entry in a time-domain resource allocation (TDRA) table for physical downlink shared channel (PDSCH) allocation; and

[0023] - K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 i} (i=1, 2, ...), where the timing information indicates slot n, for all K1 values ​​in the K1 set, slot n-K1 i and receiving a semi-static HARQ-ACK codebook at the slot n based on the determined PDSCH candidates for each slot, wherein at least one entry in the TDRA table is associated with a plurality of PDCCH-to-PDSCH slot timing K0 values, and a base station is provided where, upon determining the PDSCH candidates, the K1 set is replaced by a union of the following K sets #i:

[0024] - K set #i: {K1 i +d1,K1 i +d2,...,K1 i +d N},

[0025] where d k (k=1,2,...,N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

[0026] In yet another aspect of the present invention, there is provided a method for use by a base station in a wireless communication system, comprising the steps of transmitting a physical downlink control channel (PDCCH) having the following information:

[0027] - Index information indicating an entry in a time-domain resource allocation (TDRA) table for physical downlink shared channel (PDSCH) allocation; and

[0028] - K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 i} (i=1, 2, ...), where the timing information indicates slot n, for all K1 values ​​in the K1 set, slot n-K1 i and receiving a semi-static HARQ-ACK codebook at the slot n based on the determined PDSCH candidates for each slot, wherein based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values, when determining the PDSCH candidates, the K1 set is replaced with a union of the following K sets #i:

[0029] - K set #i: {K1 i +d1,K1 i +d2,...,K1 i +d N},

[0030] where d k (k=1,2,...,N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

[0031] Preferably, a subcarrier spacing (SCS) applied to a slot for transmitting the PDCCH may be the same as a subcarrier spacing (SCS) applied to a slot for transmitting the semi-static HARQ-ACK codebook.

[0032] Preferably, for the determined PDSCH candidates for each slot, multiple HARQ-ACK occasions are sequentially assigned to non-overlapping PDSCH candidates whose last symbols are based on the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook may be configured based on the multiple HARQ-ACK occasions.

[0033] Preferably, when time domain bundling is applied to the semi-static HARQ-ACK codebook, the multiple HARQ-ACK opportunities may be allocated based on the PDSCH candidate of the last slot where PDSCH allocation is possible for each bundling group based on each entry of the TDRA table.

[0034] Preferably, the wireless communication system may include a 3GPP (3rd generation partnership project) NR (new radio) based wireless communication system. Effect of the Invention

[0035] According to an embodiment of the present invention, it is possible to provide a method and an apparatus for efficiently transmitting and receiving a signal in a wireless communication system. Also, according to an embodiment of the present invention, it is possible to provide a method and an apparatus for efficiently transmitting a HARQ-ACK codebook in a wireless communication system. Here, the wireless communication system may include a 3GPP-based wireless communication system, for example, a 3GPP NR-based wireless communication system.

[0036] The effects obtained from the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Brief description of the drawings]

[0037] [Figure 1] FIG. 1 is a diagram illustrating an example of a radio frame structure used in a wireless communication system. [Diagram 2] FIG. 1 is a diagram illustrating an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system. [Diagram 3] FIG. 1 is a diagram illustrating physical channels used in a 3GPP system (e.g., NR) and a general signal transmission method using the physical channels. [Figure 4] A diagram showing SS / PBCH blocks for initial cell access in a 3GPP NR system. [Diagram 5] FIG. 1 illustrates a procedure for control information and control channel transmission in a 3GPP NR system. [Figure 6] A diagram showing a CORESET in which a PDCCH is transmitted in a 3GPP NR system. [Figure 7] A diagram showing a method for setting a PDCCH search space in a 3GPP NR system. [Figure 8] FIG. 1 is a conceptual diagram illustrating carrier aggregation. [Figure 9] FIG. 2 is a diagram for explaining terminal carrier communication and multi-carrier communication. [Figure 10] A diagram showing an example in which a cross-carrier scheduling technique is applied. [Figure 11] FIG. 1 is a diagram showing scheduling of a physical downlink shared channel (PDSCH). [Figure 12] FIG. 1 is a diagram illustrating scheduling of a physical uplink shared channel (PUSCH). [Figure 13]FIG. 2 is a diagram showing scheduling of PUSCH and PUCCH (physical uplink control channel). [Figure 14] FIG. 13 is a diagram showing scheduling of PDSCH using multi-slot scheduling. [Figure 15] FIG. 13 illustrates PUCCH transmission in one slot with multi-slot scheduling. [Figure 16] FIG. 1 illustrates PUCCH transmission in two or more slots with multi-slot scheduling. [Figure 17] FIG. 1 illustrates an existing Type-1 HARQ-ACK (hybrid automatic repeat request acknowledgement) codebook generation method. [Figure 18] FIG. 13 is a diagram showing PDSCH candidates corresponding to HARQ-ACK when transmitting PUCCH in slot n.

[0038] [Figure 19] FIG. 1 is a diagram showing a HARQ-ACK occasion according to an example of the present invention. [Figure 20] FIG. 2 illustrates a process for generating a HARQ-ACK codebook according to an embodiment of the present invention. [Figure 21] FIG. 2 illustrates a time domain bundling window. [Figure 22] A diagram showing a representative PDSCH by a time domain bundling window. [Figure 23] A diagram showing HARQ-ACK opportunities due to time domain bundling windows. [Figure 24] A diagram illustrating a HARQ-ACK transmission process according to an embodiment of the present invention. [Diagram 25] 2 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] The terms used in this specification are selected as common terms currently widely used as much as possible in consideration of the functions in the present invention, but this may vary depending on the intentions, customs, or the emergence of new technologies of the engineers in this field. In addition, in certain cases, the applicant may arbitrarily select some terms, and in this case, the meaning will be described in the description of the relevant invention. Therefore, it is clear that the terms used in this specification should be analyzed based on the substantial meaning of the terms and the contents of this specification as a whole, rather than simply the names of the terms.

[0040] Throughout the specification, when a certain component is "connected" to another component, this includes not only "direct connection" but also "electrical connection" through other components in between. Furthermore, when a certain component is "included" in a certain component, this does not mean excluding other components, but further includes other components, unless otherwise specified to the contrary. In addition, limitations such as "more than" or "less than" based on a specific threshold may be appropriately replaced with "more than" or "less than", respectively, depending on the embodiment.

[0041] The following technologies are 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 frequency division multiple access (SC-FDMA), etc. CDMA is implemented in radio technologies such as Universal Terrestrial Radio Access (UTRA) and CDMA2000. TDMA is implemented in radio technologies such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rates for GSM Evolution (EDGE). OFDMA is implemented in radio technologies such as IEEE802.11 (Wi-Fi), IEEE802.16 (WiMAX), IEEE802-20, Evolved UTRA (E-UTRA), etc. UTRA is part of the Universal Mobile Telecommunication System (UMTS). 3GPP LTE (Long term evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) is an evolved version of 3GPP LTE. 3GPP NR is a system designed separately from LTE / LTE-A, and is a system for supporting eMBB (enhanced Mobile BroadBand), URLLC (Ultra-Reliable and Low Latency Communication), and mMTC (massive Machine Type Communication) services, which are requirements of IMT-2020. For clarity of explanation, the following description will focus on 3GPP NR, but the technical idea of ​​the present invention is not limited thereto.

[0042] Unless otherwise specified in this specification, the base station may include a gNB (next generation node B) defined in 3GPP NR. Furthermore, unless otherwise specified, the terminal may include a UE (user equipment). Hereinafter, in order to facilitate understanding of the description, each content will be described as an individual embodiment, but each embodiment may be used in combination with each other. In this disclosure, the configuration of the terminal may mean the configuration by the base station. Specifically, the base station may transmit a channel or a signal to the terminal to configure the operation of the terminal or the value of a parameter used in the wireless communication system.

[0043] FIG. 1 is a diagram illustrating an example of a radio frame structure used in a wireless communication system.

[0044] Referring to FIG. 1, a radio frame used in a 3GPP NR system has a length of 10 ms (ΔfmaxNf / 100)*Tc). The radio frame also consists of 10 equally sized subframes (SF), where Δfmax=480*103 Hz, Nf=4096, Tc=1 / (Δfref*Nf,ref), Δfref=15*103 Hz, and Nf,ref=2048. The 10 subframes in one frame are numbered from 0 to 9. Each subframe has a length of 1 ms and consists of one or more slots depending on the subcarrier spacing. More specifically, the subcarrier spacing that can be used in a 3GPP NR system is 15*2μkHz. μ is a subcarrier spacing configuration factor, and has a value of μ=0 to 4. That is, 15 kHz, 30 kHz, 60 kHz, 120 kHz, or 240 kHz is used as the subcarrier spacing. A 1 ms long subframe consists of 2μ slots. In this case, the length of each slot is 2-μms. The 2μ slots in one subframe are numbered from 0 to 2μ-1. Also, the slots in one radio frame are numbered from 0 to 10*2μ-1. Time resources are divided by at least one of the radio frame number (also called radio frame index), subframe number (also called subframe index), and slot number (or slot index).

[0045] FIG2 illustrates an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system, and in particular, illustrates a resource grid structure in a 3GPP NR system.

[0046] There is one resource grid per antenna port. Referring to FIG. 2, a slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. An OFDM symbol also means one symbol period. Unless otherwise specified, an OFDM symbol is simply referred to as a symbol. In the following description, a symbol includes an OFDM symbol, an SC-FDMA symbol, a DFTs-OFDM symbol, and the like. Referring to FIG. 2, a signal transmitted from each slot is represented by a resource grid consisting of Nsize, μgrid, x*NRBSC subcarriers, and Nslotsymb OFDM symbols. Here, x=DL for a downlink resource grid, and x=UL for an uplink resource grid. Nsize, μgrid, and x indicate the number of resource blocks (RBs) according to a subcarrier spacing factor μ (x is DL or UL), and Nslotsymb indicates the number of OFDM symbols in a slot. NRBSC is the number of subcarriers constituting one RB, and NRBSC=12. Depending on the multiple access scheme, the OFDM symbol is called a cyclic prefix OFDM symbol (CP-OFDM) symbol or a discrete Fourier transform spread OFDM symbol (DFT-S-OFDM).

[0047] The number of OFDM symbols included in one slot may vary depending on the length of a cyclic prefix (CP). For example, a normal CP includes 14 OFDM symbols in one slot, whereas an extended CP includes 12 OFDM symbols in one slot. In a specific embodiment, the extended CP is used only at a subcarrier interval of 60 kHz. For convenience of explanation, FIG. 2 illustrates a case where one slot includes 14 OFDM symbols, but the embodiment of the present invention is also applied to slots having other numbers of OFDM symbols in the same manner. Referring to FIG. 2, each OFDM symbol includes Nsize, μgrid, and x*NRBSC subcarriers in the frequency domain. The types of subcarriers are classified into data subcarriers for transmitting data, reference signal subcarriers for transmitting a reference signal, and guard bands. The carrier frequency is also called a center frequency (fc).

[0048] One RB is defined by NRBSC (e.g., 12) consecutive subcarriers in the frequency domain. Incidentally, a resource consisting of one OFDM symbol and one subcarrier is called a resource element (RE) or tone. Thus, one RB consists of Nslotsymb*NRBSC resource elements. Each resource element in the resource grid is uniquely defined by an index pair (k, l) in one slot. k is an index ranging from 0 to Nsize,μgrid,x*NRBSC-1 in the frequency domain, and l is an index ranging from 0 to Nslotsymb-1 in the time domain.

[0049] In order for a terminal to receive a signal from a base station or transmit a base station signal, the time / frequency synchronization of the terminal should be aligned with the time / frequency synchronization of the base station, because if the base station and the terminal are not synchronized, the terminal cannot determine the time and frequency parameters required to demodulate DL signals and transmit UL signals at the correct time.

[0050] Each symbol of a radio frame operating in time division duplex (TDD) or unpaired spectrum consists of at least one of downlink symbol (DL symbol), uplink symbol (UL symbol) or flexible symbol. A radio frame operating in frequency division duplex (FDD) or paired spectrum with a downlink carrier consists of downlink symbols or flexible symbols, and a radio frame operating with an uplink carrier consists of uplink symbols or flexible symbols. A downlink symbol allows downlink transmission but not uplink transmission, and an uplink symbol allows uplink transmission but not downlink transmission. Whether a flexible symbol is used in the downlink or uplink is determined depending on the signal.

[0051] Information on the type of each symbol, i.e., information indicating any one of the downlink symbol, the uplink symbol, and the flexible symbol, is composed of a cell-specific (cell-specific or common) RRC signal. In addition, the information on the type of each symbol is additionally composed of a specific terminal (UE-specific or dedicated) RRC signal. The base station uses the cell-specific RRC signal to inform i) the period of the cell-specific slot configuration, ii) the number of slots having only downlink symbols from the beginning of the period of the cell-specific slot configuration, iii) the number of downlink symbols from the first symbol in the slot immediately after the slot having only downlink symbols, iv) the number of slots having only uplink symbols from the end of the period of the cell-specific slot configuration, and v) the number of uplink symbols from the last symbol in the slot immediately before the slot having only uplink symbols. Here, a symbol that is not configured as either an uplink symbol or a downlink symbol is a flexible symbol.

[0052] If the information regarding the symbol type consists of the UE-specific RRC signal, the base station signals, via the cell-specific RRC signal, whether the flexible symbol is a downlink symbol or an uplink symbol. At this time, the UE-specific RRC signal cannot change a downlink symbol or an uplink symbol that consists of the cell-specific RRC signal to another symbol type. The UE-specific RRC signal signals, for each slot, the number of downlink symbols among the Nslotsymb symbols of the slot and the number of uplink symbols among the Nslotsymb symbols of the slot. At this time, the downlink symbols of the slot are continuously configured from the first symbol to the i-th symbol of the slot. Also, the uplink symbols of the slot are continuously configured from the j-th symbol to the last symbol of the slot (where i < j). In a slot, a symbol that is not configured as either an uplink symbol or a downlink symbol is a flexible symbol.

[0053] The type of symbol configured by the RRC signal as described above can be called a semi-static DL / UL configuration. In the semi-static DL / UL configuration configured by the RRC signal previously, the flexible symbol may be indicated as a downlink symbol, an uplink symbol, or a flexible symbol by the dynamic SFI (slot format information) transmitted on the physical downlink control channel (PDCCH). At this time, a downlink symbol or an uplink symbol configured by the RRC signal is not changed to another symbol type. Table 1 exemplifies the dynamic SFI that the base station can indicate to the UE.

[0054]

Table 1

[0055] In Table 1, D represents a downlink symbol, U represents an uplink symbol, and X represents a flexible symbol. As shown in Table 1, up to two DL / UL switchings may be allowed in one slot.

[0056] FIG. 3 is a diagram illustrating physical channels used in a 3GPP system (eg, NR) and a general signal transmission method using the physical channels.

[0057] When a terminal is powered on or enters a new cell, the terminal performs an initial cell search operation S101. More specifically, the terminal synchronizes with a base station in the initial cell search. To this end, the terminal receives 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. Next, the terminal receives a physical broadcast channel from the base station to obtain broadcast information within the cell.

[0058] After completing the initial cell search, the terminal receives a physical downlink shared channel (PDSCH) via a physical downlink control channel (PDCCH) and information carried on the PDCCH, thereby acquiring more detailed system information than the system information acquired through the initial cell search (S102).

[0059] When a terminal first connects to a base station or when there are no radio resources for signal transmission (when the terminal is in RRC_IDLE mode), the terminal can perform a random access procedure with respect to the base station (steps S103 to S106). First, the terminal transmits a preamble on a physical random access channel (PRACH) (S103) and can receive a response message for the preamble from the base station on a PDCCH and a corresponding PDSCH (S104). If the terminal receives a valid random access response message, the terminal transmits data including its own identifier, etc. to the base station on a physical uplink shared channel (PUSCH) indicated by an uplink grant transmitted from the base station on the PDCCH (S105). Next, the terminal waits to receive a PDCCH as an instruction from the base station to resolve collisions. If the terminal successfully receives a PDCCH with its own identifier (S106), the random access procedure ends.

[0060] After the above-mentioned procedure, the terminal receives PDCCH / PDSCH S107 and transmits physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) S108 as a general uplink / downlink signal transmission procedure. In particular, the terminal receives downlink control information (DCI) through the PDCCH. The DCI includes control information such as resource allocation information for the terminal. The format of the DCI may differ depending on the purpose of use. The uplink control information (UCI) transmitted by the terminal to the base station through the uplink includes downlink / uplink ACK / NACK signals, a channel quality indicator (CQI), a precoding matrix index (PMI), a rank indicator (RI), etc. Here, the CQI, PMI, and RI are included in channel state information (CSI). In the case of a 3GPP NR system, the terminal transmits control information such as the above-mentioned HARQ-ACK and CSI using the PUSCH and / or PUCCH.

[0061] FIG. 4 is a diagram illustrating SS / PBCH blocks for initial cell access in a 3GPP NR system.

[0062] When a terminal is powered on or attempts to access a new cell, it acquires time and frequency synchronization with the cell and performs an initial cell search process. The terminal detects the physical cell identity (NcellID) of the cell during the cell search process. To this end, the terminal receives synchronization signals, such as a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), from the base station to synchronize with the base station. At this time, the terminal obtains information such as a cell identity (ID).

[0063] With reference to FIG. 4(a), the synchronization signal (SS) will be described in more detail. The synchronization signal is divided into PSS and SSS. The PSS is used to obtain time domain synchronization and / or frequency domain synchronization such as OFDM symbol synchronization and slot synchronization. The SSS is used to obtain frame synchronization and cell group ID. With reference to FIG. 4(a) and Table 1, the SS / PBCH block consists of 20 RBs (=240 subcarriers) consecutive on the frequency axis and 4 OFDM symbols consecutive on the time axis. In this case, in the SS / PBCH block, the PSS is transmitted in the first OFDM symbol and the SSS is transmitted in the third OFDM symbol via the 56th to 18th 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 does not transmit signals via the remaining subcarriers, i.e., the 0th to 55th and 183rd to 239th subcarriers. In addition, in the third OFDM symbol in which the SSS is transmitted, the base station does not transmit signals via subcarriers 48 to 55 and 183 to 19. The base station transmits a physical broadcast channel (PBCH) via the remaining REs in the SS / PBCH block excluding the above-mentioned signals.

[0064] [Table 2]

[0065] The SS is grouped into 336 physical layer cell ID groups, each of which includes three unique identifiers, so that a total of 1008 unique physical layer cell IDs are obtained through a combination of three PSSs and SSSs, more specifically, each physical layer cell ID is part of only one physical layer cell ID group. Thus, a physical layer cell ID NcellID=3N(1)ID+N(2)ID is uniquely defined by an index N(1)ID ranging from 0 to 335 indicating a physical layer cell ID group and an index N(2)ID ranging from 0 to 2 indicating a physical layer identifier in the physical layer cell ID group. The UE detects the PSS and identifies one of the three unique physical layer identifiers. The UE also detects the SSS and identifies one of the 336 physical layer cell IDs associated with the physical layer identifier. In this case, the sequence dPSS(n) of the PSS is expressed as the following Equation 1.

[0066] d PSS (n)=1-2x(m) m = (n + 43N (2) ID ) mod 127 0≦n<127

[0067] where x(i+7)=(x(i+4)+x(i)) mod 2,

[0068] Given: [x(6)x(5)x(4)x(3)x(2)x(1)x(0)]=[1110110].

[0069] Also, the SSS sequence dSSS(n) is as follows:

[0070] d SSS (n)=[1-2x0((n+m0) mod 127][1-2x1((n+m1) mod 127] m0=15 floor(N (1) ID / 112)+5N (2) ID m1=N (1) ID mod 112 0≦n<127

[0071] Here, x0(i+7)=(x0(i+4)+x0(i))mod 2 x1(i+7)=(x1(i+1)+x1(i))mod 2,

[0072] Given that [x0(6)x0(5)x0(4)x0(3)x0(2)x0(1) 0(0)]=[0000001], [x1(6)x1(5)x1(4)x1(3)x1(2)x1(1)x1(0)]=[0000001].

[0073] A radio frame with a length of 10 ms is divided into two half-frames with a length of 5 ms. The slots in each half-frame in which the SS / PBCH block is transmitted will be described with reference to FIG. 4(b). The slots in which the SS / PBCH block is transmitted are any one of cases A, B, C, D, and E. In case A, the subcarrier spacing is 15 kHz, and the start point of the SS / PBCH block is the {2, 8}+14*nth symbol. In this case, n=0, 1 for carrier frequencies below 3 GHz. Also, n=0, 1, 2, 3 for carrier frequencies above 3 GHz and below 6 GHz. In case B, the subcarrier spacing is 30 kHz, and the start point of the SS / PBCH block is the {4, 8, 16, 20}+28*nth symbol. In this case, n=0 for carrier frequencies below 3 GHz. Also, n=0, 1 for carrier frequencies above 3 GHz and below 6 GHz. In case C, the subcarrier spacing is 30 kHz and the start of the SS / PBCH block is {2, 8}+14*n symbols, where n=0, 1 for carrier frequencies below 3 GHz. Also, n=0, 1, 2, 3 for carrier frequencies above 3 GHz and below 6 GHz. In case D, the subcarrier spacing is 120 kHz and the start of the SS / PBCH block is {4, 8, 16, 20}+28*n symbols, where n=0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18 for carrier frequencies above 6 GHz. In case E, the subcarrier spacing is 240 kHz and the start of the SS / PBCH block is {8, 12, 16, 20, 32, 36, 40, 44}+56*n symbols. In this case, n=0, 1, 2, 3, 5, 6, 7, 8 for carrier frequencies of 6 GHz or higher.

[0074] Figure 5 is a diagram showing a procedure for transmitting control information and a control channel in a 3GPP NR system. Referring to Figure 5(a), a base station adds a cyclic redundancy check (CRC) masked (e.g., XORed) with a radio network temporary identifier (RNTI) to control information (e.g., DCI) S202. The base station scrambles the CRC with an RNTI value determined according to the purpose / target of each control information. The common RNTI used by one or more terminals includes 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). Also, the UE-specific RNTI includes at least one of C-RNTI (cell temporary RNTI), CS-RNTI, or MCS-C-RNTI. Next, the base station performs channel encoding (e.g., polar coding) S204, and then performs rate-matching according to the amount of resource(s) used for PDCCH transmission S206. Next, the base station multiplexes DCI(s) based on a PDCCH structure based on a control channel element (CCE) S208. In addition, the base station applies additional processes such as scrambling, modulation (e.g., QPSK), and interleaving to the multiplexed DCI(s) S210, and maps them to resources to be transmitted. A CCE is a basic resource unit for a PDCCH, and one CCE consists of a plurality of (e.g., 6) resource element groups (REGs). One REG consists of a plurality of (e.g., 12) REs. The number of CCEs used for one PDCCH is defined as an aggregation level. 3GPP NR systems use aggregation levels of 1, 2, 4, 8, or 16.FIG. 5(b) is a diagram relating to CCE aggregation levels and PDCCH multiplexing, showing the types of CCE aggregation levels used for one PDCCH and the CCE(s) transmitted in the control region accordingly.

[0075] FIG. 6 is a diagram showing a CORESET in which a PDCCH is transmitted in a 3GPP NR system.

[0076] A CORESET is a time-frequency resource in which a PDCCH, which is a control signal for a terminal, is transmitted. A search space, which will be described later, is mapped to one CORESET. Thus, a terminal does not monitor all frequency bands to receive a PDCCH, but monitors a time-frequency region designated as a CORESET and decodes a PDCCH mapped to the CORESET. A base station configures one or more CORESETs for each cell in a terminal. A CORESET is made up of up to three consecutive symbols on the time axis. Also, a CORESET is made up of six units of PRBs that are consecutive on the frequency axis. In the embodiment of FIG. 5, CORESET#1 is made up of consecutive PRBs, and CORESET#2 and CORESET#3 are made up of discontinuous PRBs. A CORESET may be located at any symbol in a slot. For example, in the embodiment of FIG. 5, CORESET#1 starts from the first symbol of a slot, CORESET#2 starts from the fifth symbol of a slot, and CORESET#9 starts from the ninth symbol of a slot.

[0077] FIG. 7 is a diagram illustrating a method for setting a PDCCH search space in a 3GPP NR system.

[0078] In order to transmit a PDCCH to a terminal, at least one or more search spaces exist in each CORESET. In an embodiment of the present invention, the search space is a set of all time-frequency resources (hereinafter, PDCCH candidates) in which the PDCCH of the terminal is transmitted. The search space includes a common search space that 3GPP NR terminals should commonly search, and a terminal-specific or UE-specific search space that a specific terminal should search. In the common search space, all terminals in a cell belonging to the same base station monitor a PDCCH that is set to be commonly searched. In addition, the terminal-specific search space is set for each terminal so that the PDCCH allocated to each terminal is monitored at a position of the search space that differs from one another according to the terminal. In the case of the terminal-specific search space, the search spaces between terminals may be partially overlapped due to the limited control region to which the PDCCH is allocated. Monitoring the PDCCH includes blind decoding the PDCCH candidates in the search space. If blind decoding is successful, it is expressed as the PDCCH being (successfully) detected / received, and if blind decoding is unsuccessful, it is expressed as the PDCCH being undetected / not received or not successfully detected / received.

[0079] For convenience of explanation, a PDCCH scrambled with a group common (GC) RNTI already known by one or more terminals to transmit downlink control information to one or more terminals is referred to as a group common (GC) PDCCH or a common PDCCH. Also, a PDCCH scrambled with a terminal-specific RNTI already known by a specific terminal to transmit uplink scheduling information or downlink scheduling information to one specific terminal is referred to as a terminal-specific PDCCH. The common PDCCH is included in a common search space, and the terminal-specific PDCCH is included in a common search space or a terminal-specific PDCCH.

[0080] The base station uses the PDCCH to notify each terminal or terminal group of information regarding resource allocation of the transmission channels PCH (paging channel) and DL-SCH (downlink-shared channel) (i.e., DL Grant), or information regarding UL-SCH resource allocation and hybrid automatic repeat request (HARQ) (i.e., UL Grant). The base station transmits PCH transport blocks and DL-SCH transport blocks on the PDSCH. The base station transmits data excluding specific control information or specific service data on the PDSCH. In addition, the terminal receives data excluding specific control information or specific service data on the PDSCH.

[0081] The base station transmits information on which terminal (one or more terminals) the PDSCH data is transmitted to and how the terminal should receive and decode the PDSCH data by including it in the PDCCH. For example, assume that the DCI transmitted on a specific PDCCH is CRC masked with RNTI "A", the DCI indicates that the PDSCH is allocated to radio resource "B" (e.g., frequency position) and indicates transmission format information "C" (e.g., transmission block size, modulation method, coding information, etc.). The terminal monitors the PDCCH using its own RNTI information. In this case, if there is a terminal that blind decodes the PDCCH using RNTI "A", the terminal receives the PDCCH and receives the PDSCH indicated by "B" and "C" through the received PDCCH information.

[0082] Table 3 shows one embodiment of a PUCCH used in a wireless communication system.

[0083] [Table 3]

[0084] The PUCCH is used to transmit the following uplink control information (UCI):

[0085] - SR (Scheduling Request): Information used to request uplink UL-SCH resources.

[0086] - HARQ-ACK: a response to a PDCCH (indicating DL semi-persistent scheduling (SPS) release) and / or a response to an uplink transport block (TB) on a PDSCH. HARQ-ACK indicates whether information transmitted on a PDCCH or PDSCH has been received. HARQ-ACK responses include positive ACK (simply, ACK), negative ACK (hereinafter, NACK), Discontinuous Transmission (DTX), or NACK / DTX. Here, the term HARQ-ACK is used interchangeably with HARQ-ACK / NACK and ACK / NACK. In general, ACK is represented by a bit value of 1 and NACK is represented by a bit value of 0.

[0087] - CSI: Feedback information for a downlink channel. It is generated by a terminal based on a CSI-RS (Reference Signal) transmitted by a base station. MIMO (multiple input multiple output)-related feedback information includes RI and PMI. CSI is divided into CSI part 1 and CSI part 2 according to the information indicated by CSI.

[0088] In the 3GPP NR system, five PUCCH formats are used to support various service scenarios and various channel environments and frame structures.

[0089] PUCCH format 0 is a format that transmits 1-bit or 2-bit HARQ-ACK information or SR. PUCCH format 0 is transmitted through one or two OFDM symbols on the time axis and one RB on the frequency axis. If PUCCH format 0 is transmitted with two OFDM symbols, the same sequence is transmitted with different RBs for the two symbols. Through this, the terminal obtains frequency diversity gain. More specifically, the terminal determines a cyclic shift value mcs according to the Mbit bit UCI (Mbit=1 or 2), and transmits a sequence obtained by cyclically shifting a base sequence of length 12 by the determined value mcs, by mapping the sequence to 12 REs of one OFDM symbol and one PRB. If the number of cyclic shifts available to the terminal is 12 and Mbit=1, 1-bit UCI 0 and 1 are represented by sequences corresponding to two cyclic shifts with a cyclic shift value difference of 6. Also, if Mbit=2, then 2-bit UCI 00, 01, 11, 10 is represented by a sequence corresponding to four cyclic shifts with a difference between the cyclic shift values ​​being three.

[0090] PUCCH format 1 transmits 1-bit or 2-bit HARQ-ACK information or SR. PUCCH format 1 is transmitted through continuous OFDM symbols on the time axis and one PRB on the frequency axis. Here, the number of OFDM symbols occupied by PUCCH format 1 is one of 4 to 14. More specifically, UCI with Mbit=1 is modulated by BPSK. The terminal modulates UCI with Mbit=2 by quadrature phase shift keying (QPSK). A signal is obtained by multiplying the modulated complex valued symbol d(0) by a sequence of length 12. The terminal transmits the obtained signal by spreading it by a time-axis orthogonal cover code (OCC) on even-numbered OFDM symbols to which PUCCH format 1 is assigned. In PUCCH format 1, the maximum number of different terminals multiplexed in the same RB can be determined according to the length of the OCC used. In odd-numbered OFDM symbols of PUCCH format 1, a demodulation reference signal (DMRS) is spread by OCC and mapped.

[0091] PUCCH format 2 transmits UCI exceeding 2 bits. PUCCH format 2 is transmitted through one or two OFDM symbols on the time axis and one or more RBs on the frequency axis. If PUCCH format 2 is transmitted through two OFDM symbols, the same sequence is transmitted through two OFDM symbols in different RBs. In this way, the terminal obtains frequency diversity gain. More specifically, Mbit UCI (Mbit>2) is bit-level scrambled and QPSK modulated to be mapped to RBs of one or two OFDM symbol(s). Here, the number of RBs is one of 1 to 16.

[0092] PUCCH format 3 or PUCCH format 4 transmits UCI exceeding 2 bits. PUCCH format 3 or PUCCH format 4 is transmitted through continuous 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 is one of 4 to 14. In particular, the terminal modulates Mbit UCI (Mbit>2) with π / 2-BPSK (Binary Phase Shift Keying) or QPSK to generate complex symbols d(0) to d(Msymb-1). Here, Msymb=Mbit when π / 2-BPSK is used, and Msymb=Mbit / 2 when QPSK is used. The terminal does not apply block-wise spreading to PUCCH format 3. However, the terminal may apply block-wise spreading to one RB (i.e., 12 subcarriers) using PreDFT-OCC of length -12 so that PUCCH format 4 has a multiplexing capacity of 2 or 4. The terminal transmit precoding (or DFT-precoding) the spread signal, maps it to each RE, and transmits the spread signal.

[0093] In this case, the number of RBs occupied by PUCCH format 2, PUCCH format 3, or PUCCH format 4 is determined according to the length of UCI transmitted by the terminal and the maximum code rate. If the terminal uses PUCCH format 2, the terminal transmits both HARQ-ACK information and CSI information on the PUCCH. If the number of RBs required for UCI transmission is greater than the maximum number of RBs available for PUCCH format 2, PUCCH format 3, or PUCCH format 4, the terminal does not transmit some UCI information and transmits only the remaining UCI information according to the priority of the UCI information.

[0094] PUCCH format 1, PUCCH format 3, or PUCCH format 4 is configured via RRC signaling to indicate frequency hopping within a slot. When frequency hopping is configured, the index of the RB to be frequency hopped is configured via RRC signaling. If PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted across N OFDM symbols in the time axis, the first hop has floor(N / 2) OFDM symbols and the second hop has ceil(N / 2) OFDM symbols.

[0095] PUCCH format 1, PUCCH format 3, or PUCCH format 4 is configured to be repeatedly transmitted in multiple slots. In this case, the number K of slots in which the PUCCH is repeatedly transmitted is configured by an RRC signal. The repeatedly transmitted PUCCH should start from the same OFDM symbol position in each slot and have the same length. If the RRC signal indicates that any one of the OFDM symbols in a slot in which the UE should transmit the PUCCH is a DL symbol, the UE does not transmit the PUCCH from the slot, but postpones it to the next slot for transmission.

[0096] Meanwhile, in a 3GPP NR system, a terminal transmits and receives using a bandwidth smaller than or equal to the bandwidth of a carrier (or cell). To this end, the terminal is configured with a BWP (bandwidth part) consisting of a continuous bandwidth of a part of the carrier bandwidth. A terminal operating according to TDD or in an unpaired spectrum is configured with up to four DL / UL BWP pairs for one carrier (or cell). The terminal also activates one DL / UL BWP pair. A terminal operating according to FDD or in a paired spectrum is configured with up to four DL BWPs for a downlink carrier (or cell) and up to four UL BWPs for an uplink carrier (or cell). The terminal activates one DL BWP and one UL BWP for each carrier (or cell). The terminal may not receive or transmit from time-frequency resources other than the activated BWP. The activated BWP is called an active BWP.

[0097] The base station refers to an activated BWP among the BWPs configured for the terminal as a DCI. The BWP indicated by the DCI is activated, and the other configured BWP(s) are deactivated. In a carrier (or cell) operating in TDD, the base station includes a BPI (bandwidth part indicator) indicating the activated BWP in the DCI for scheduling the PDSCH or PUSCH to change the DL / UL BWP pair of the terminal. The terminal receives the DCI for scheduling the PDSCH or PUSCH and identifies the activated DL / UL BWP pair based on the BPI. In the case of a downlink carrier (or cell) operating in FDD, the base station includes a BPI indicating the activated BWP in the DCI for scheduling the PDSCH to change the DL BWP of the terminal. In the case of an uplink carrier (or cell) operating in FDD, the base station includes a BPI indicating the activated BWP in the DCI for scheduling the PDSCH to change the UL BWP of the terminal.

[0098] FIG. 8 is a conceptual diagram illustrating carrier aggregation.

[0099] Carrier aggregation refers to a method in which a terminal uses multiple frequency blocks or (logical) cells consisting of uplink resources (or component carriers) and / or downlink resources (or component carriers) in one large logical frequency band in order for a wireless communication system to use a wider frequency band. For convenience of explanation, the term "component carrier" will be used hereinafter.

[0100] Referring to FIG. 8, as an example of a 3GPP NR system, the entire system band includes up to 16 component carriers, and each component carrier has a bandwidth of up to 400 MHz. The component carrier includes one or more physically contiguous subcarriers. Although each component carrier is shown to have the same bandwidth in FIG. 8, this is merely an example, and each component carrier may have a different bandwidth. Also, although each component carrier is shown to be adjacent to each other on the frequency axis, the drawing is a logical concept, and each component carrier may be physically adjacent to each other or separated from each other.

[0101] A different center frequency is used in each component carrier. Also, a common center frequency is used in physically adjacent component carriers. In the embodiment of FIG. 8, if it is assumed that all component carriers are physically adjacent, center frequency A is used in all component carriers. Also, if it is assumed that each component carrier is not physically adjacent, center frequency A and center frequency B are used in each component carrier.

[0102] When the entire system band is expanded by carrier aggregation, the frequency band used for communication with each terminal is defined in component carrier units. Terminal A uses the entire system band of 100 MHz and communicates using all five component carriers. Terminals B1 to B5 use only a 20 MHz bandwidth and communicate using one component carrier. Terminals C1 and C2 use only a 40 MHz bandwidth and communicate using two component carriers each. The two component carriers may be logically / physically adjacent or not adjacent. The embodiment of FIG. 8 shows a case where terminal C1 uses two non-adjacent component carriers and terminal C2 uses two adjacent component carriers.

[0103] 9 is a diagram for explaining terminal carrier communication and multi-carrier communication. In particular, FIG. 9(a) shows a subframe structure of a single carrier, and FIG. 9(b) shows a subframe structure of a multi-carrier.

[0104] Referring to FIG. 9(a), a general wireless communication system transmits or receives data through one DL band and one corresponding UL band in the FDD mode. In another specific embodiment, in the TDD mode, the wireless communication system divides a wireless frame into an uplink time unit and a downlink time unit in the time domain, and transmits or receives data through the uplink / downlink time unit. Referring to FIG. 9(b), three 20 MHz component carriers (CCs) are aggregated in the UL and DL, respectively, to support a bandwidth of 60 MHz. The CCs are adjacent or non-adjacent to each other in the frequency domain. Although FIG. 9(b) illustrates a case in which the bandwidth of the UL CC and the bandwidth of the DL CC are the same and symmetrical for convenience, the bandwidth of each CC may be determined independently. Also, asymmetric carrier aggregation in which the number of UL CCs and the number of DL CCs are different is possible. The DL / UL CC allocated / configured to a specific terminal through RRC is called a serving DL / UL CC of the specific terminal.

[0105] The base station activates some or all of the serving CCs of the terminal, or deactivates some of the CCs to communicate with the terminal. The base station may change the CCs to be activated / deactivated, or may change the number of CCs to be activated / deactivated. When the base station allocates CCs available to the terminal in a cell-specific or terminal-specific manner, at least one of the CCs once allocated may not be deactivated unless the CC allocation for the terminal is completely reconfigured or the terminal performs a handover. A CC that is not deactivated by the terminal is called a primary CC (PCC) or PCell (primary cell), and a CC that the base station can activate / deactivate freely is called a secondary CC (SCC) or SCell (secondary cell).

[0106] Meanwhile, 3GPP NR uses the concept of a cell to manage radio resources. A cell is defined as a combination of downlink and uplink resources, i.e., a combination of DL CC and UL CC. A cell consists of DL resources alone or a combination of DL and UL resources. If carrier aggregation is supported, the linkage between the carrier frequency of DL resources (or DL ​​CC) and the carrier frequency of UL resources (or UL CC) is indicated by system information. Carrier frequency means the center frequency of each cell or CC. A cell corresponding to a PCC is called a PCell, and a cell corresponding to a SCC is called a SCell. A carrier corresponding to a PCell in the downlink is a DL PCC, and a carrier corresponding to a PCell in the uplink is a UL PCC. Similarly, a carrier corresponding to a SCell in the downlink is a DL SCC, and a carrier corresponding to a SCell in the uplink is a UL SCC. Depending on the terminal capacity, a serving cell(s) consists of one PCell and zero or more SCells. For a UE in RRC_CONNECTED state but with no carrier aggregation configured or that does not support carrier aggregation, there is only one serving cell consisting of only a PCell.

[0107] As described above, the term cell used in carrier aggregation is different from the term cell referring to a certain geographical area to which communication services are provided by one base station or one antenna group. However, in order to distinguish between a cell referring to a certain geographical area and a cell of carrier aggregation, in the present invention, a cell of carrier aggregation is referred to as CC, and a cell of a geographical area is referred to as cell.

[0108] FIG. 10 is a diagram showing an example in which a cross-carrier scheduling technique is applied. If cross-carrier scheduling is configured, a control channel transmitted through a first CC schedules a data channel transmitted through a first CC or a second CC using a carrier indicator field (CIF). The CIF is included in the DCI. In other words, a scheduling cell is configured, and a DL grant / UL grant transmitted from a PDCCH region of the scheduling cell schedules a PDSCH / PUSCH of a scheduled cell. That is, a search region for multiple component carriers is the PDCCH region of the scheduling cell. A PCell is basically a scheduling cell, and a specific SCell is designated as a scheduling cell by a higher layer.

[0109] In the embodiment of FIG. 10, it is assumed that three DL CCs are merged. 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 SCC (or SCell). It is also assumed that DL PCC is configured as PDCCH monitoring CC. If cross-carrier scheduling is not configured by UE-specific (or UE-group-specific, or cell-specific) higher layer signaling, the CIF is disabled, and each DL CC transmits only a PDCCH that schedules its own PDSCH without a CIF according to the NR PDCCH rule (non-cross-carrier scheduling, self-carrier scheduling). On the other hand, if cross-carrier scheduling is configured by UE-specific (or UE-group-specific, or cell-specific) higher layer signaling, the CIF is enabled, and a specific CC (e.g., DL PCC) transmits not only a PDCCH that schedules the PDSCH of DL CC A but also a PDCCH that schedules the PDSCH of another CC using the CIF (cross-carrier scheduling). In contrast, no PDCCH is transmitted in other DL CCs. Therefore, depending on whether cross-carrier scheduling is configured in the terminal, the terminal monitors a PDCCH that does not include a CIF to receive a self-carrier scheduled PDSCH, or monitors a PDCCH that includes a CIF to receive a cross-carrier scheduled PDSCH.

[0110] 9 and 10 illustrate the subframe structure of a 3GPP LTE-A system, the same or similar configuration can be applied to a 3GPP NR system, however, in the 3GPP NR system, the subframes in FIG. 9 and 10 may be replaced with slots.

[0111] A method for receiving a PDCCH / PDSCH and a method for transmitting a PUCCH / PUSCH in a terminal will be described with reference to FIG. 11 and FIG.

[0112] The terminal can receive DCI formats on the PDCCH. The DCI formats include the following:

[0113] - DCI format 0_x (x = 0, 1, 2): DCI format for scheduling PUSCH transmission (hereinafter referred to as DL grant (DG) DCI format, or DG DCI)

[0114] - DCI format 1_x (x = 0, 1, 2): DCI format for scheduling PDSCH reception (hereinafter referred to as UL grant (UG) DCI format, or UG DCI)

[0115] When the terminal receives a DCI format (i.e., a DG DCI format) that schedules a PDSCH, the terminal can receive a PDSCH scheduled by the DG DCI format. To this end, the terminal can analyze (determine) i) a slot in which the PDSCH is scheduled and ii) a starting index / length of a symbol in the slot from the DG DCI format. A time domain resource assignment (TDRA) field of the DG DCI format can indicate (i) a K0 value that is timing information (e.g., a slot offset) of the slot, and (ii) a starting length indicator value (SLIV) that is an index / length of a starting symbol in the slot. Here, the K0 value may be a non-negative integer value. The SLIV may be a value obtained by jointly encoding the index (S) / length (L) value of the starting symbol in the slot. The SLIV may also be a value in which the index (S) / length (L) value of the starting symbol in the slot is separately transmitted. For example, in a regular CP, S may have any one of the values ​​0, 1, ..., 13, and L may have any one of the values ​​of natural numbers such that S+L is less than or equal to 14. In an extended CP, S may have any one of the values ​​0, 1, ..., 11, and L may have any one of the values ​​of natural numbers such that S+L is less than or equal to 12.

[0116] The terminal can determine the slot in which the PDSCH is received based on the K0 value. Specifically, the terminal can determine the slot in which the PDSCH is received based on (i) the K0 value, (ii) the index of the slot in which the DG DCI is received, (iii) the SCS of the (DL) BWP in which the DG DCI is received (i.e., the SCS applied to the DG DCI), and (iv) the SCS of the (DL) BWP in which the PDSCH is received (i.e., the SCS applied to the PDSCH).

[0117] As an example, assume that (i) the SCS of the BWP in which the DG DCI is received is the same as (ii) the SCS of the BWP in which the PDSCH is received. In this case, assume that the DG DCI is received in DL slot n. In this case, the PDSCH corresponding to the DG DCI is received in DL slot n+K0.

[0118] As another example, assume that the SCS of the BWP in which the DG DCI is received is 15kHz*2^mu_PDCCH, and the SCS of the BWP in which the PDSCH is received is 15kHz*2^mu_PDSCH. In this case, assume that the DG DCI is received in DL slot n. Here, the index of DL slot n is an index according to the SCS of the BWP in which the DG DCI is received. In this case, the PDSCH corresponding to the DG DCI is received in DL slot floor(n*2^mu_PDSCH / 2^mu_PDCCH)+K0. Here, the index of DL slot floor(n*2^mu_PDSCH / 2^mu_PDCCH)+K0 is an index according to the SCS of the BWP in which the PDSCH is received. mu_PDCCH and mu_PDSCH may have values ​​of 0, 1, 2, and 3, respectively.

[0119] Referring to FIG 11, it is assumed that the UE receives a PDCCH that schedules a PDSCH in DL slot n. It is also assumed that the DCI transmitted on the PDCCH indicates K0=3. It is also assumed that (i) the SCS of the DL BWP in which the PDCCH is received (i.e., the SCS applied to the PDCCH; PDCCH SCS) is the same as (ii) the SCS of the DL BWP in which the PDSCH is scheduled (i.e., the SCS applied to the PDSCH; PDSCH SCS). In this case, the UE can determine that the PDSCH is scheduled in DL slot n+K0, i.e., slot n+3.

[0120] The terminal can determine the symbol to which the PDSCH is assigned using the index (S) of the starting symbol and the value of the length (L) in the slot determined based on the K0 value. The symbols to which the PDSCH is assigned are symbol S to symbol S+L-1 in the slot determined based on the K0 value. Here, symbol S to symbol S+L-1 are L consecutive symbols.

[0121] The terminal may further be configured with a DL slot aggregation from the base station. The DL slot aggregation value may be 2, 4, or 8. When the DL slot aggregation is configured, the terminal may receive the PDSCH in consecutive slots corresponding to the slot aggregation value, starting from the slot determined based on the K0 value.

[0122] When the terminal receives a DCI format (e.g., DG DCI format) that schedules a PUCCH, the terminal may transmit the scheduled PUCCH. Here, the PUCCH may include HARQ-ACK information. A PDSCH-to-HARQ_feedback timing indicator field included in the DG DCI format may indicate a K1 value for information of a slot in which the PUCCH is scheduled. Here, the K1 value may be a non-negative integer value. The K1 value of DCI format 1_0 may indicate any one of the values ​​of {0, 1, 2, 3, 4, 5, 6, 7} (hereinafter, K1 set). The K1 value of DCI formats 1_1 and 1_2 may indicate any one of the K1 values ​​(i.e., K1 set) configured / set by a higher layer (e.g., RRC).

[0123] The HARQ-ACK information may be two types of HARQ-ACK information for whether the channel is successfully received. As a first type, when the PDSCH is scheduled by DCI format 1_x, the HARQ-ACK information may be HARQ-ACK for whether the PDSCH is successfully received. As a second type, when the DCI format 1_x is a DCI instructing the release of the SPS PDSCH, the HARQ-ACK information may be HARQ-ACK for whether the DCI formats 1_0, 1_1, and 1_2 are successfully received.

[0124] The terminal may determine a slot in which a PUCCH including the first type of HARQ-ACK information is transmitted as follows. The terminal may determine an (UL) slot #A that overlaps with the last symbol of a PDSCH corresponding to the HARQ-ACK information. If the index of the (UL) slot #A is m, the index of the (UL) slot #B in which the terminal transmits a PUCCH including the HARQ-ACK information may be m+K1. Here, the index of the (UL) slot is a value according to the SCS of the UL BWP in which the PUCCH is transmitted (i.e., the SCS applied to the PUCCH; the SCS of the PUCCH). Meanwhile, when a DL slot set is configured in the terminal, the last symbol of the PDSCH represents the last symbol of the PDSCH scheduled in the last slot among the slots in which the PDSCH is received.

[0125] Referring to FIG. 12, assume that the UE receives a PDCCH that schedules a PDSCH in DL slot n. Assume also that the DCI in the PDCCH indicates K0=3 and K1=2. Assume also that the SCS of the DL BWP in which the PDCCH is received (i.e., the SCS of the PDCCH), the SCS of the DL BWP in which the PDSCH is scheduled (i.e., the SCS of the PDSCH), and the SCS of the UL BWP in which the PUCCH is transmitted (i.e., the SCS of the PUCCH) are the same. In this case, the UE can determine that the PDSCH is scheduled in DL slot n+K0, i.e., slot n+3. The UE can also determine a UL slot that overlaps with the last symbol of the PDSCH scheduled in DL slot n+3. Here, the last symbol of the PDSCH in DL slot n+3 overlaps with UL slot n+3. Therefore, the UE can transmit the PUCCH in UL slot n+3+K1, i.e., slot n+5.

[0126] The terminal may determine a slot for transmitting a PUCCH including the second type of HARQ-ACK information as follows: The terminal may determine an UL slot #A that overlaps with the last symbol of a PDCCH (e.g., a PDCCH carrying SPS release DCI) corresponding to the HARQ-ACK information. If the index of UL slot #A is m, the index of UL slot #B in which the terminal transmits a PUCCH including the HARQ-ACK information may be m+K1. Here, the index of the UL slot is a value according to the SCS of the UL BWP in which the PUCCH is transmitted (i.e., the SCS of the PUCCH).

[0127] With reference to FIG. 13, it is assumed that the UE receives a PDCCH carrying an SPS PDSCH release DCI in DL slot n. It is assumed that the DCI carried in the PDCCH indicates K1=3. It is also assumed that the SCS of the DL BWP in which the PDCCH is received is the same as the SCS of the UL BWP in which the PUCCH is transmitted. In this case, the UE can determine a UL slot n that overlaps with the last symbol of the PDCCH in DL slot n. In this case, the UE can determine that a PUCCH carrying a HARQ-ACK for the SPS PDSCH release DCI is scheduled in UL slot n+K1, i.e., UL slot n+3.

[0128] When the terminal receives a DCI format (i.e., UG DCI format) that schedules a PUSCH, the terminal can transmit the scheduled PUSCH. To do so, the terminal must analyze (determine) from the DCI (i) the slot in which the PUSCH is scheduled and (ii) the starting index and length of the symbol in the slot. The TDRA field of the UG DCI format can indicate (i) a K2 value for the information of the scheduled slot, and (ii) an SLIV, which is a value for the information of the index and length of the starting symbol in the slot. Here, the K2 value may be a non-negative integer value. Here, the SLIV may be a value obtained by jointly encoding the values ​​of the index (S) and length (L) of the starting symbol in the slot. In addition, the SLIV may be a value in which the values ​​of the index (S) and length (L) of the starting symbol in the slot are transmitted separately. For example, in a regular CP, S may have any one of the values ​​0, 1, ..., 13, and L may have any one of the values ​​of natural numbers that satisfy the condition that S + L is less than or equal to 14. In the extended CP, S may have any one of the values ​​0, 1, . . . , 11, and L may have any one of the values ​​of natural numbers that satisfy the condition that S+L is less than or equal to 12.

[0129] The terminal may determine a slot in which the PUSCH is scheduled based on the K2 value. Specifically, the terminal may determine a slot in which the PUSCH should be transmitted based on the K2 value, an index of a slot in which the UG DCI is received, and an SCS of the DL BWP in which the UG DCI is received or an SCS of the UL BWP in which the PUSCH is transmitted.

[0130] As an example, assume that (i) the SCS of the DL BWP in which the UG DCI is received is the same as (ii) the SCS of the UL BWP in which the PUSCH is transmitted. Also assume that the UG DCI is received in DL slot n. In this case, the PUSCH may be transmitted in UL slot n+K2.

[0131] As another example, assume that the SCS of the DL BWP in which the UG DCI is received is 15kHz*2^mu_PDCCH, and the SCS of the UL BWP in which the PUSCH is transmitted is 15kHz*2^mu_PUSCH. Also assume that the UG DCI is received in DL slot n. Here, the index of DL slot n is an index according to the SCS of the DL BWP in which the UG DCI is received (i.e., the SCS of the UG DCI). In this case, the PUSCH may be transmitted in slot floor(n*2^mu_PUSCH / 2^mu_PDCCH)+K2. Here, the slot index floor(n*2^mu_PUSCH / 2^mu_PDCCH)+K2 is an index according to the SCS of the UL BWP in which the PUSCH is transmitted. Here, mu_PDCCH or mu_PUSCH may have values ​​of 0, 1, 2, or 3.

[0132] With reference to FIG. 13, it is assumed that the UE receives a PDCCH that schedules a PUSCH in DL slot n. It is also assumed that the DCI transmitted on the PDCCH indicates K2=3. It is also assumed that the SCS of the DL BWP in which the PDCCH is received is the same as the SCS of the UL BWP in which the PUCCH is transmitted. In this case, the UE can determine that a PUSCH is scheduled in UL slot n+K2=n+3.

[0133] The terminal can determine the symbol to which the PUSCH is assigned using the index (S) of the start symbol and the value of the length (L) in the slot determined based on the K2 value. The symbols to which the PUSCH is assigned are symbol S to symbol S+L-1 in the slot determined based on the K2 value. Here, symbol S to symbol S+L-1 are L consecutive symbols.

[0134] The UE may further receive a UL slot set from the base station. The UL slot set value may be 2, 4, or 8. When the UL slot set is set, the UE may transmit a PUSCH in consecutive slots corresponding to the slot set value, starting from the slot determined based on the K2 value.

[0135] 11 to 13, the terminal uses K0, K1, and K2 values ​​to determine a slot in which the PDSCH is received, a slot in which the PUCCH is transmitted, and a slot in which the PUSCH is transmitted. For convenience, the slots obtained by assuming that the K0, K1, and K2 values ​​are 0 are called reference points or reference slots.

[0136] In FIG. 11, the reference slot to which the K0 value applies is DL slot n in which the PDCCH is received.

[0137] In FIG. 12, the reference slot to which the K1 value applies is the UL slot that overlaps with the last symbol of the PDSCH, ie, UL slot n+3.

[0138] In Figure 13, the reference slot to which the K1 value is applied is the UL slot that overlaps with the last symbol of the PDCCH, that is, UL slot n, and the reference slot to which the K2 value is applied is UL slot n.

[0139] For convenience, in the following description, it is assumed that the SCS of the DL BWP in which the PDSCH / PDCCH is received is the same as the SCS of the UL BWP in which the PUSCH / PUCCH is transmitted. In addition, the UL slot and the DL slot are not separately distinguished and are referred to as slots.

[0140] In the above description, the UE receives one DCI and receives a PDSCH or transmits a PUSCH in one slot based on the DCI. However, when one DCI provides only scheduling information for one slot, the UE must transmit the same number of DCIs as the number of slots in order to schedule multiple slots. This may result in waste of DL resources.

[0141] To solve this problem, a method may be used in which a terminal receives one DCI from a base station and receives PDSCH in multiple slots based on the DCI. Here, the PDSCH received in each slot may include separate DL data (e.g., DL-SCH data). More specifically, the PDSCH received in each slot may include separate transport blocks (TBs). Also, the PDSCH received in each slot may have separate HARQ process numbers. Also, the PDSCH received in each slot may occupy separate symbols in each slot.

[0142] Also, a method may be used in which a terminal receives one DCI from a base station and transmits PUSCH in multiple slots based on the DCI. Here, the PUSCH transmitted in each slot may include individual UL data (e.g., UL-SCH data). More specifically, the PUSCH transmitted in each slot may include an individual TB. Also, the PUSCH transmitted in each slot may have an individual HARQ process number. Also, the PUSCH transmitted in each slot may occupy an individual symbol in each slot.

[0143] As described above, receiving a PDSCH or transmitting a PUSCH in multiple slots based on one DCI is referred to as multi-slot scheduling for convenience.

[0144] For reference, multi-slot scheduling differs from the existing slot aggregation (a method of repeatedly receiving a PDSCH or repeatedly transmitting a PUSCH in a plurality of slots) in the following points.

[0145] - Conventional slot aggregation is a scheme in which a PDSCH or PUSCH having the same TB is repeatedly received or transmitted in multiple slots to expand coverage and improve reliability, whereas multi-slot scheduling is a scheme in which a PDSCH or PUSCH having an individual TB is received or transmitted in multiple slots to reduce PDCCH overhead.

[0146] - In the existing DL slot set, since PDSCH including the same TB is received in multiple slots, whether or not the same TB is successfully received is determined from the PDSCH received in multiple slots. Therefore, the terminal transmits a HARQ-ACK for the same TB to the base station. However, in multi-slot scheduling, since the PDSCH received in multiple slots includes individual TBs, the terminal must determine whether or not the reception is successful for each TB. In addition, the terminal must transmit a HARQ-ACK to the base station for each TB.

[0147] Multi-slot scheduling will be explained with reference to FIGS.

[0148] Referring to FIG. 14, one DCI may schedule PDSCH reception in multiple slots. In FIG. 14, a PDCCH including one DCI may be received in slot n. The TDRA field of the one DCI may indicate a timing information K0 value of the scheduled slot, an index of a starting symbol in each slot, and a SLIV value that is a length. More specifically, a first slot in which a PDSCH is transmitted may be determined based on the K0 value. PDSCH reception may be scheduled in M ​​consecutive slots from the first slot determined by the K0 value. In FIG. 14, K0=3, M=3. Therefore, PDSCH reception may be scheduled in slot n+3, slot n+4, and slot n+5. A terminal may be indicated with an index (S) of a starting symbol for PDSCH reception and a number (L) of consecutive symbols in a slot. (S, L) may be the same or different for each slot. If (S, L) are different for each slot, the index (S) of the starting symbol for receiving the PDSCH and the number (L) of consecutive symbols may be indicated for each slot.

[0149] Table 4 shows a TDRA table used for multi-slot scheduling as an example. The TDRA table may be configured with 12 entries, and each entry may be indexed from 0 to 11. At least one entry may be configured to schedule PDSCH in multiple slots. For example, each entry may schedule PDSCH in up to four slots. To this end, each entry may be given up to four SLIV values ​​and a K0 value. Here, the K0 value indicates the difference between the slot in which the PDCCH is received and the slot in which the PDSCH is received (PDCCH-to-PDSCH slot offset). The SLIV indicates the starting index (S) of the symbol in which the PDSCH is received in one slot and the number of consecutive symbols (L). In Table 4, the PDSCH scheduled in one slot may be expressed as (K0, S, L).

[0150] If multi-slot scheduling can schedule PDSCH in consecutive slots, the K0 value indicating the slot to be scheduled may be omitted in the TDRA table. For example, referring to Table 5, each entry in the TDRA table may include only one K0 value. And, each entry (or at least one entry) in the TDRA table may include two or more SLIV values ​​(i.e., (S, L)). In this case, PDSCH reception may be scheduled at a symbol corresponding to a first SLIV value (first (S, L)) in a slot determined by the K0 value, and PDSCH reception may be scheduled at a symbol corresponding to a second SLIV value (second (S, L)) in the next slot. Specifically, in the TDRA table, K0 of each entry may be set as {K0 r ,K0 r +i,...,K0 r +M r -1}. Here, K0 r denotes K0 of the r-th entry, and M r corresponds to the number of SLIV values ​​included in the rth entry.

[0151] If multi-slot scheduling can schedule PDSCH in non-consecutive slots, the TDRA table may include (i) a K0 value and (ii) an offset (O) value. Here, the offset value represents the (slot index) difference between the slot indicated by the K0 value and the slot in which PDSCH reception is indicated. For example, referring to Table 6, each entry in the TDRA table may include only one K0 value. And each SLIV may further have an offset value (O in Table 6). For reference, the offset value may be omitted in the SLIV for the slot indicated by the K0 value. Therefore, the K0 of each entry in the TDRA table is expressed as {K0 r ,K0 r +O 1,r ,...,K0 r +O M-1,r} where K0 r represents K0 of the r-th entry, and O i,rrepresents the (slot) offset value for the i-th scheduling of the r-th entry, and M corresponds to the number of SLIV values ​​included in each entry.

[0152] As another example, if multi-slot scheduling can schedule the PDSCH in non-consecutive slots, the TDRA table may have the structure of Table 7.

[0153] [Table 4]

[0154] [Table 5]

[0155] [Table 6]

[0156] [Table 7]

[0157] For the sake of convenience, the present invention will be described with respect to a case where the PDSCH is scheduled in a plurality of consecutive slots. Therefore, unless otherwise specified, the K0 value is omitted. However, the present invention also includes a case where the PDSCH is scheduled in a plurality of non-consecutive slots (see Table 7).

[0158] Referring to FIG. 15, the HARQ-ACK of the PDSCH scheduled to be received in multiple slots by one DCI may be transmitted on the PUCCH in one slot. Here, the UL slot that overlaps with the end of the last PDSCH among the PDSCHs received in multiple slots may be determined as the UL slot with K1 value 0. In FIG. 15, UL slot n+5 is the UL slot with K1 value 0 and corresponds to the reference slot. The terminal may be indicated with one K1 value from the one DCI. In this case, the HARQ-ACK of the PDSCH scheduled for multi-slots may be transmitted in the UL slot corresponding to the one K1.

[0159] Referring to FIG. 16, the HARQ-ACK of the PDSCH scheduled to be received in multiple slots by one DCI may be transmitted on the PUCCH in two or more slots. The method for this is as follows. First, the multi-slot scheduled PDSCH can be grouped. Here, when the PDSCH is grouped, the PDSCHs that are consecutive in time order (i.e., sequentially according to time) can be grouped into one group. In FIG. 16, one DCI schedules the PDSCH to be received in three slots. Among the three slot PDSCHs, the first two PDSCHs can be grouped into one group (group 0) and the last PDSCH can be grouped into another group (group 1). The specific method for grouping is as follows.

[0160] As a first method, the terminals can be grouped based on the number of PDSCHs scheduled by one DCI. Here, if the number of PDSCHs is greater than a certain number, only the certain number of PDSCHs can be grouped together to form one group. For example, if the certain number is 2 and the number of PDSCHs is 4, two PDSCHs can be grouped together to form a group. Here, the certain number can be set by the base station.

[0161] As a second method, the terminal may be grouped based on the number of groups predefined by one DCI. That is, the terminal may be configured with the number of predefined groups by the base station. For example, if the number of predefined groups is 2 and the number of PDSCHs scheduled by one DCI is 6, the 6 PDSCHs may be divided into 2 groups. In this case, the PDSCHs may be grouped into one group in sequence according to time (order), and the number of PDSCHs included in each group may be the same as much as possible, with a maximum difference of 1.

[0162] As a third method, grouping information may be set for each entry of the TDRA. Specifically, each entry of the TDRA includes information for receiving PDSCH in multiple slots. Information regarding which slots' PDSCHs are grouped into one group may be included here. That is, together with the SLIV of each slot, an index of the group including the SLIV may be included. With reference to Table 8, an index (G) of the group including the SLIV may be included in each entry of the TDRA table. Here, an SLIV belonging to G=0 corresponds to group 0, and an SLIV belonging to G=1 corresponds to group 1.

[0163] [Table 8]

[0164] The UE can transmit the HARQ-ACK of the PDSCH included in one group on the PUCCH of the UL slot. Here, the method of determining the UL slot includes determining the UL slot that overlaps with the end time of the last PDSCH included in the group as the UL slot (i.e., reference slot) with K1 value of 0. That is, in FIG. 16, the reference slot of group 0 is slot n+4, and the reference slot of group 1 is slot n+5.

[0165] The terminal may receive one K1 value from the one DCI. In this case, the terminal may transmit HARQ-ACK of PDSCH scheduled to be received by the one DCI in multiple slots in an UL slot corresponding to the one K1 for each group. For example, in FIG. 16, K1=2. HARQ-ACK of two PDSCHs included in group 0 is transmitted in PUCCH of slot n+4+2 (=reference slot index of group 0+K1), and HARQ-ACK of one PDSCH included in group 1 is transmitted in PUCCH of slot n+7 (=reference slot index of group 1+K1).

[0166] The terminal may be instructed by the one DCI to have a K1 value for each group. In this case, the terminal may transmit HARQ-ACK of PDSCH scheduled to be received by the one DCI in multiple slots in an UL slot corresponding to K1 of each group for each group. For example, K1 value=1 may be assigned to group 0, and K1 value=2 may be assigned to group 1. In this case, HARQ-ACK of two PDSCHs included in group 0 is transmitted in PUCCH of slot n+4+K1 (=reference slot index of group 0+K1 of group 0), and HARQ-ACK of one PDSCH included in group 1 is transmitted in PUCCH of slot n+7 (=reference slot index of group 1+K1 of group 1).

[0167] Hereinafter, the present invention will describe a method for transmitting HARQ-ACK for PDSCHs when the PDSCHs are scheduled by multi-slot scheduling.

[0168] In an NR wireless communication system, a terminal may transmit a codebook including HARQ-ACK information to signal whether a DL signal / channel (requiring HARQ-ACK feedback) is successfully received. The HARQ-ACK codebook includes one or more bits indicating whether a DL channel / signal is successfully received. Here, the DL channel / signal (requiring HARQ-ACK feedback) may include at least one of i) a PDSCH, ii) a semi-persistence scheduling (SPS) PDSCH, and iii) a PDCCH indicating an SPS PDSCH release. The HARQ-ACK codebook type may be classified into a semi-static HARQ-ACK codebook (or a Type-1 HARQ-ACK codebook) and a dynamic HARQ-ACK codebook (or a Type-2 HARQ-ACK codebook). The base station may configure one of two HARQ-ACK codebook types for the terminal. Based on the configured HARQ-ACK codebook type, the terminal can generate and transmit a HARQ-ACK codebook for the DL channel / signal.

[0169] Type-1 (or semi-static) HARQ-ACK codebook

[0170] When a semi-static HARQ-ACK codebook is used, the base station can use RRC signaling to pre-configure information (e.g., K1 set) used to determine the number of bits of the HARQ-ACK codebook and whether each bit of the HARQ-ACK codebook indicates which DL signal / channel has been successfully received. Therefore, the base station does not need to signal information required for HARQ-ACK codebook transmission to the terminal every time it needs to transmit the HARQ-ACK codebook.

[0171] Specifically, in the existing single slot scheduling, the method of generating a Type-1 HARQ-ACK codebook is as follows: In single slot scheduling, DCI schedules one slot of PDSCH. For convenience, it is assumed that the Type-1 HARQ-ACK codebook is transmitted in slot n. Here, slot n may be determined by the value of the PDSCH-to-HARQ_feedback indicator (i.e., K1) of DCI format 1_x (PDCCH).

[0172] 1) Step 1: Let K1_set be a set of K1 values ​​that can be specified by DCI. For DCI format 1_0, K1_set is {0, 1, 2, 3, 4, 5, 6, 7}. For DCI formats 1_1 and 1_2, K1_set may be configured / set by a higher layer (e.g., RRC). The terminal first extracts the maximum K1 value (hereinafter, K1_max) in K1_set. Then, K1_max is excluded from K1_set.

[0173] 2) Step 2: Let R be the set of PDSCH candidates receivable in slot n-K1_max. The PDSCH candidates included in set R have a starting symbol and length in the slot according to the TDRA table. If a symbol of a PDSCH candidate included in set R overlaps with a symbol configured as UL in the semi-static UL / DL configuration by at least one symbol, the PDSCH candidate is excluded from set R.

[0174] 3) Step 3: The terminal performs steps A and B for the PDSCH candidates included in R.

[0175] - Step A: A new HARQ-ACK opportunity is assigned to the PDSCH candidate in set R whose last symbol is the earliest. If there is a PDSCH candidate in set R whose last symbol overlaps with the PDSCH candidate whose last symbol is the earliest by at least one symbol, the same HARQ-ACK opportunity is assigned to the PDSCH candidate. The PDSCH candidates to which the HARQ-ACK opportunity is assigned (i.e., (i) the PDSCH candidate whose last symbol is the earliest and (ii) the PDSCH candidate whose last symbol overlaps with the PDSCH candidate by at least one symbol) are excluded from set R.

[0176] - Step B: Repeat step A until set R is an empty set.

[0177] 4) Repeat steps 1), 2), and 3) until K1_set becomes an empty set.

[0178] Then, the terminal may generate a Type-1 HARQ-ACK codebook based on the assigned HARQ-ACK opportunity. For example, if a PDSCH corresponding to a HARQ-ACK opportunity is received, the HARQ-ACK opportunity may be set to HARQ-ACK information of the PDSCH. However, if no PDSCH corresponding to the HARQ-ACK opportunity is received, the HARQ-ACK opportunity may be set to NACK. One HARQ-ACK opportunity may include one or more HARQ-ACK bits. For example, if a PDSCH includes one TB (or if spatial bundling is configured for TBs in a PDSCH), the HARQ-ACK opportunity may include one HARQ-ACK bit. Also, if a PDSCH includes two TBs (and spatial bundling is not configured), the HARQ-ACK opportunity may include two HARQ-ACK bits. Furthermore, when CBG (code block group)-based PDSCH reception is configured, the HARQ-ACK opportunity may include HARQ-ACK bits corresponding to the maximum number of CBGs that one PDSCH can include.

[0179] FIG. 17 illustrates PDSCH candidate positions and HARQ-ACK opportunities when K1_set={0, 1, 2, 3, 4} in the existing single slot scheduling. Referring to FIG. 17, the UE i It is possible to determine receivable PDSCH candidates with K1 i corresponds to the i-th value after sorting K1_set in descending order. Therefore, the terminal can determine a set R of PDSCH candidates in each slot of {slot n-4, ..., slot n} and assign HARQ-ACK opportunities to the PDSCH candidates in set R. For convenience, it is assumed that one HARQ-ACK opportunity is assigned to the PDSCH candidate in each slot, and one bit is assumed per HARQ-ACK opportunity. Thus, the Type-1 HARQ-ACK codebook is composed of five HARQ-ACK bits (o0 to o4).

[0180] Thereafter, for convenience of explanation, we assume 1 bit per HARQ-ACK opportunity.

[0181] Meanwhile, when PDSCH is scheduled by multi-slot scheduling, if the existing method is applied as it is, the Type-1 HARQ-ACK codebook cannot be correctly configured. For the sake of explanation, assume that K1_set={1,2} is set to the terminal by RRC. Thus, the terminal may be instructed to K1=1 or K1=2 by the PDSCH-to-HARQ_feedback indicator in the DCI. When the TDRA table of Table 4 is set, the PDSCH candidates corresponding to the HARQ-ACK to be transmitted on the PUCCH in slot n are as shown in FIG. 18. However, the existing Type-1 HARQ-ACK codebook generation method determines the set R of PDSCH candidates receivable in slot n-K1_max based only on the K1 value of K1_set. Therefore, only the PDSCH candidates of slot n-2 and slot n-1 can be used to generate the Type-1 HARQ-ACK codebook (see the dotted box in FIG. 18).

[0182] Hereinafter, a method for generating a Type-1 HARQ-ACK codebook when PDSCH is scheduled by multi-slot scheduling will be proposed. In the following description, refer to Table 4 and FIG. 18. Multi-slot scheduling operation may be set for each cell (or component carrier). Among all cells configured in the UE, cells for which multi-slot scheduling is not set may operate according to the existing single-slot scheduling method.

[0183] Proposal 1: Intra-slot PDSCH candidate based

[0184] Proposal 1 is a method of converting a multi-slot scheduled PDSCH into a PDSCH candidate for each slot, and generating a Type-1 HARQ-ACK codebook using the PDSCH candidate in each slot. For example, the method of generating a Type-1 HARQ-ACK codebook according to proposal 1 is as follows.

[0185] 1) Phase 1: Let K1_set be the set of K1 values ​​that can be instructed to the terminal. In Proposal 1, the terminal can determine the index of the slot in which the PDSCH candidate corresponding to the Type-1 HARQ-ACK codebook is located / received based on K1_set and the TDRA table. Let K_slot be the set of such slot indexes.

[0186] Specifically, the method of determining K_slot is as follows. The terminal can select one K1 value from K1_set. Let the selected K1 value be K1_a. At this time, based on K1_a and the TDRA table, the terminal can determine which slot the terminal should receive PDSCH. For example, if the TDRA table includes PDSCH allocation information for up to N consecutive slots, the terminal can determine {slot n-K1_a-(N-1), slot n-K1_a-(N-2), ..., slot n-K1_a} as PDSCH allocation information based on K1_a and the TDRA table. Therefore, the K_slot set may include {K1_a+(N-1), K1_a+(N-2), ..., K1_a}. For reference, the TDRA table may also include PDSCH allocation information for non-consecutive slots. Here, slot n is the slot to which the Type-1 HARQ-ACK codebook is transmitted, and N is the number of slots scheduled in the TDRA table from the first to the last. Among {slot n-K1_a-(N-1) to slot n-K1_a}, slots that are not scheduled by the TDRA table may be excluded. Finally, K_slot(K1_a)={K1_a+(N-1),K1_a+(N-2),...,K1_a} is defined. (Ni) corresponds to the slot index difference between the last slot available for PDSCH allocation and the i-th slot available for PDSCH allocation based on the TDRA table. Here, the slot index difference corresponds to the difference between KO values: for example, (Ni)=(K0 max -KO i ), where K0 max represents the maximum value of K0, and KO irepresents the i-th KO value (see Table 4). K_slot(K1_a) corresponds to the union of K_slots determined for each K1_a / entry: K_slot(K1_a,r)={K1_a+(Nr-1),K1_a+(Nr-2),...,K1_a}. Here, r represents the entry index in the TDRA table, and Nr corresponds to the number of PDSCH / slot allocation information (e.g., KO, SLIV) included in the r-th entry in the TDRA table. Here, (Nr-i) is the sum of (K0 max,r -KO i,r ), where K0 max,r represents the maximum value of multiple KO values ​​corresponding to the rth entry in the TDRA table, and KO i represents the i-th KO value among multiple KO values ​​corresponding to the r-th entry in the TDRA table (see Table 4).

[0187] The same operation may be performed for the remaining K1 values ​​in K1_set to obtain the indexes of slots capable of receiving PDSCH candidates for all K1 values ​​in K1_set, and the indexes may be collected / lumped together and included in the K_slot set.

[0188] 2) 2nd stage: Extract the maximum K1 value (K1_max) in K_slot. Then, K1_max is excluded from K_slot. Corresponding to the existing 1st stage, K_slot is used instead of K1_set.

[0189] 3) Step 3: Let R be a set of PDSCH candidates receivable in slot n-K1_max. If a symbol of a PDSCH candidate included in set R overlaps with a symbol configured as UL in the semi-static UL / DL configuration by at least one symbol, the PDSCH candidate is excluded from set R.

[0190] The PDSCH candidates included in the set R in slot n-K1_max can be obtained as follows. The terminal can select one K1 value from K1_set. Let the selected K1 value be K1_a. Based on the K1_a value and the TDRA table, the terminal can determine the PDSCH candidates in the multi-slot. For example, if one entry in the TDRA table includes PDSCH allocation information for M consecutive slots, the terminal can determine {slot n-K1_a-(M-1), slot n-K1_a-(M-2), ..., slot n-K1_a} as the PDSCH allocation information based on K1_a and the TDRA table. If one slot of slot {n-K1_a-(M-1), slot n-K1_a-(M-2), ..., slot n-K1_a} is slot n-K1_max, the PDSCH candidate included in slot n-K1_max may be included in the set R. The above process may be performed for all entries in the TDRA table, and for all K1 values ​​in K1_set.

[0191] 4) Step 4: The terminal performs steps A and B for the PDSCH candidates in set R.

[0192] - Step A: A new HARQ-ACK opportunity is assigned to the PDSCH candidate whose last symbol is the earliest among the PDSCH candidates in set R. Then, if there is a PDSCH candidate in set R whose last symbol overlaps with the PDSCH candidate whose last symbol is the earliest by at least one symbol, the same HARQ-ACK opportunity is assigned to the PDSCH candidate. The PDSCH candidates to which the HARQ-ACK opportunity is assigned (i.e., (i) the PDSCH candidate whose last symbol is the earliest and (ii) the PDSCH candidate whose last symbol overlaps with the PDSCH candidate by at least one symbol) are excluded from set R.

[0193] - Step B: Repeat step A until set R is an empty set.

[0194] 5) 5th step: Repeat steps 2 / 3 / 4 until K_slot becomes an empty set.

[0195] Proposal 1 will be explained with reference to FIG.

[0196] 1) Step 1: K1_set={1,2} since 1 and 2 are set as K1 values ​​(by RRC). The terminal can determine K_slot by the following process.

[0197] The terminal selects one of the values ​​of K1_set. Let this be K1_a=2. Since an entry in the TDRA table includes PDSCH allocation information for a maximum of N=4 consecutive slots, based on K1_a=2 and the TDRA table, the terminal can determine {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, slot n-K1_a=n-2} as PDSCH allocation information. Therefore, K_slot(K1_a=2) includes {5, 4, 3, 2}. K_slot(K1_a=2) corresponds to the union of K_slot(K1_a=2,r).

[0198] - K_slot(K1_a=2, r=0~2): {K1_a+(Nr-1)=2+(2-1)=3, K1_a+(Nr-2)=2+(2-2)=2} or {K1_a+(K0max,r-K01,r)=2+(1-0)=3, K1_a+(K0max,r-K02,r)=2+(1-1)=2}

[0199] - K_slot(K1_a=2, r=3~5):{5,4,3,2}

[0200] - K_slot(K1_a=2, r=6~11):{3,2}

[0201] The terminal selects one remaining value from K1_set. Let this be K1_a=1. Since an entry in the TDRA table includes PDSCH allocation information for a maximum of N=4 consecutive slots, based on K1_a=1 and the TDRA table, the terminal can determine {slot n-K1_a-(N-1)=n-1-(4-1)=n-4, slot n-K1_a-(N-2)=n-1-(4-2)=n-3, slot n-K1_a-(N-3)=n-1-(4-3)=n-2, slot n-K1_a=n-1} as PDSCH allocation information. Therefore, K_slot(K1_a=1) includes {4, 3, 2, 1}. K_slot(K1_a=1) corresponds to the union of K_slot(K1_a=1,r).

[0202] - K_slot(K1_a=1, r=0~2): {K1_a+(Nr-1)=1+(2-1)=2, K1_a+(Nr-2)=1+(2-2)=1} or {K1_a+(K0max,r-K01,r)=1+(1-0)=2, K1_a+(K0max,r-K02,r)=1+(1-1)=1}

[0203] - K_slot(K1_a=1, r=3~5):{4,3,2,1}

[0204] - K_slot(K1_a=1, r=6~11):{2,1}

[0205] Therefore, finally, K_slot contains {5,4,3,2,1} (i.e., the union of K_slot(K1_a=2) and K_slot(K1_a=1)).

[0206] 2) Step 2: Select the maximum value K1_max=5 from K_slot. Then, K1_max=5 is excluded from K_slot.

[0207] 3) Step 3: Let R be a set of PDSCH candidates receivable in slot n-K1_max=n-5. If a symbol of a PDSCH candidate included in set R overlaps with a symbol configured as UL in the semi-static UL / DL configuration, the PDSCH candidate is excluded from set R. For ease of explanation, in this example, it is assumed that all symbols in the slot are DL symbols.

[0208] The PDSCH candidates included in set R in slot n-5 can be obtained as follows.

[0209] The terminal selects one of the values ​​of K1_set. Let this be K1_a=2. Entries 3, 4, and 5 of the TDRA table include PDSCH allocation information for four (M) consecutive slots, i.e., {slot n-K1_a-(M-1)=n-5, slot n-K1_a-(M-2)=n-4, slot n-K1_a-(M-3)=n-3, slot n-K1_a-(M-4)=n-2}, and the remaining entries (0, 1, 2, 6, 7, 8, 9, 10, 11) include PDSCH allocation information for two consecutive slots, i.e., {slot n-3, slot n-2}. Therefore, entries 3, 4, and 5 of the TDRA table include a PDSCH candidate for slot n-K1_max=n-5, so the PDSCH candidate included in slot n-5 may be included in set R. That is, the set R of PDSCH candidates receivable in slot n-K1_max=n-5 includes: {(S=0,L=14), (S=0,L=7), (S=7,L=7)}. For reference, (S=0,L=14) is the PDSCH candidate for slot n-5 in entry 3 of the TDRA table, (S=0,L=7) is the PDSCH candidate for slot n-5 in entry 4 of the TDRA table, and (S=7,L=7) is the PDSCH candidate for slot n-5 in entry 5 of the TDRA table.

[0210] Select one remaining value from K1_set. Let this be K1_a=1. Entries 3, 4, and 5 of the TDRA table contain PDSCH allocation information for four (M) consecutive slots, i.e., {slot n-K1_a-(M-1)=n-4, slot n-K1_a-(M-2)=n-3, slot n-K1_a-(M-3)=n-2, slot n-K1_a-(M-4)=n-1}, and the remaining entries (0, 1, 2, 6, 7, 8, 9, 10, 11) contain PDSCH allocation information for two consecutive slots, i.e., {slot n-2, slot n-1}. Therefore, the slot corresponding to K1_a=1 does not overlap with slot n-K1_max=n-5, so there is no PDSCH candidate to include in set R.

[0211] Therefore, R = {(S = 0, L = 14), (S = 0, L = 7), (S = 7, L = 7)}.

[0212] 4) Step 4: The terminal performs steps A and B for the PDSCH candidates in set R.

[0213] - Step A: Among the PDSCH candidates in set R, assign HARQ-ACK opportunity 0 to the PDSCH candidate (S=0,L=7) whose last symbol is the earliest. Then, assign the same HARQ-ACK opportunity to the PDSCH candidate (S=0,L=14) in set R that overlaps with the PDSCH candidate (S=0,L=7) for even one symbol. The PDSCH candidates (S=0,L=7) and (S=0,L=14) to which the HARQ-ACK opportunity is assigned are excluded from set R. Therefore, the set R={(S=7,L=7)}.

[0214] - Step B: Repeat step A until set R is an empty set. In this example, since set R is not an empty set, repeat step A. Step A assigns HARQ-ACK opportunity 1 to PDSCH candidates (S=7, L=7), and set R becomes an empty set. This completes the 4th stage.

[0215] 5) 5th step: Repeat 2 / 3 / 4 steps until K_slot is an empty set. In this example, K_slot={4,3,2,1}, so it is not an empty set. Since K_slot is not an empty set, repeat 2 / 3 / 4 steps.

[0216] Through these steps, PDSCH candidates and HARQ-ACK opportunities are determined as follows:

[0217] HARQ-ACK opportunity 0: PDSCH candidate for slot n-5 (S=0,L=7), (S=0,L=14)

[0218] HARQ-ACK opportunity 1: PDSCH candidate in slot n-5 (S=7, L=7)

[0219] HARQ-ACK opportunity 2: PDSCH candidate in slot n-4 (S=0,L=7), (S=0,L=14)

[0220] HARQ-ACK opportunity 3: PDSCH candidate in slot n-4 (S=7, L=7)

[0221] HARQ-ACK opportunity 4: PDSCH candidate in slot n-3 (S=0,L=7), (S=0,L=14)

[0222] HARQ-ACK opportunity 5: PDSCH candidate in slot n-3 (S=7, L=7)

[0223] HARQ-ACK opportunity 6: PDSCH candidate in slot n-2 (S=0,L=7), (S=0,L=14)

[0224] HARQ-ACK opportunity 7: PDSCH candidate in slot n-2 (S=7, L=7)

[0225] HARQ-ACK opportunity 8: PDSCH candidate in slot n-1 (S=0,L=7), (S=0,L=14)

[0226] HARQ-ACK opportunity 9: PDSCH candidate in slot n-1 (S=7, L=7)

[0227] Therefore, the Type-1 HARQ-ACK codebook may consist of 10 HARQ-ACK opportunities.

[0228] For example, assume that the DCI received by the terminal indicates (i) entry 4 in the TDRA table and (ii) K1=2. In this case, the terminal receives the first PDSCH (S=0,L=7) in slot n-5, the second PDSCH (S=0,L=7) in slot n-4, the third PDSCH (S=0,L=7) in slot n-3, and the fourth PDSCH (S=0,L=7) in slot n-2. The terminal includes the HARQ-ACK (o1) for the first PDSCH in HARQ-ACK opportunity 0, the HARQ-ACK (o2) for the second PDSCH in HARQ-ACK opportunity 2, the HARQ-ACK (o3) for the third PDSCH in HARQ-ACK opportunity 4, and the HARQ-ACK (o4) for the fourth PDSCH in HARQ-ACK opportunity 6. Therefore, the Type-1 HARQ-ACK codebook may be constructed as [o1 N o2 N o3 N o4 NNN], where N denotes NACK.

[0229] Assume further that the DCI received by the terminal indicates (i) entry 5 in the TDRA table and (ii) K1=1. In this case, the terminal receives the fifth PDSCH (S=7,L=7) in slot n-4, the sixth PDSCH (S=7,L=7) in slot n-3, the seventh PDSCH (S=7,L=7) in slot n-2, and the eighth PDSCH (S=7,L=7) in slot n-1. The terminal includes the HARQ-ACK (o5) for the fifth PDSCH in HARQ-ACK opportunity 3, the HARQ-ACK (o6) for the sixth PDSCH in HARQ-ACK opportunity 5, the HARQ-ACK (o7) for the seventh PDSCH in HARQ-ACK opportunity 7, and the HARQ-ACK (o8) for the eighth PDSCH in HARQ-ACK opportunity 9. Therefore, the Type-1 HARQ-ACK codebook may be constructed as [o1 N o2 o5 o3 o6 o4 o7 N o8], where N denotes NACK.

[0230] Proposal 1 creates HARQ-ACK opportunities using PDSCH candidates in each slot. However, one DCI can schedule PDSCH in multiple slots, so creating HARQ-ACK opportunities using PDSCH candidates in each slot may be inefficient. For example, in FIG. 19, a terminal may be scheduled with a maximum of eight PDSCHs at any time. This is the case as follows:

[0231] (TDRA table entry 4 and K1=2, TDRA table entry 5 and K1=2)

[0232] (TDRA table entry 4 and K1=2, TDRA table entry 5 and K1=1)

[0233] (TDRA table entry 4 and K1=1, TDRA table entry 5 and K1=2)

[0234] (TDRA table entry 4 and K1=1, TDRA table entry 5 and K1=1)

[0235] Therefore, the Type-1 HARQ-ACK codebook transmitted by the terminal only needs to include eight HARQ-ACK opportunities. However, according to Proposal 1, ten HARQ-ACK opportunities are included. Therefore, two HARQ-ACK opportunities are always unused when transmitting HARQ-ACK information.

[0236] FIG. 20 illustrates a method for constructing a HARQ-ACK codebook according to Proposal 1.

[0237] Referring to FIG. 20, the terminal may receive a PDCCH having the following information (S2002): (i) index information indicating an entry in the TDRA table for PDSCH allocation, and (ii) a K1 set {K1 i} (i=1, 2, ...). When the timing information indicates slot n, the terminal performs slot n-K1 for all K1 values ​​in the K1 set. i The terminal may then determine a PDSCH candidate for slot n (S2004). Then, the terminal may transmit a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot.

[0238] Here, if multi-slot scheduling is configured (e.g., if at least one entry in the TDRA table is associated with multiple PDCCH-to-PDSCH slot timing K0 values), then when determining the PDSCH candidates, the K1 set may be replaced by the union of the following K sets #i:

[0239] - K set #i: {K1 i +d1,K1 i +d2,...,K1 i +d N},

[0240] where dk (k=1, 2, ..., N) corresponds to the slot index difference between the last slot for which a PDSCH can be assigned and the kth slot for which a PDSCH can be assigned based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

[0241] Here, the SCS applied to the PDCCH and the SCS applied to the semi-static HARQ-ACK codebook may be the same. In addition, for the determined PDSCH candidates of each slot, a plurality of HARQ-ACK opportunities may be sequentially allocated to non-overlapping PDSCH candidates based on the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook may be configured based on the plurality of HARQ-ACK opportunities. In addition, when time domain bundling, which will be described later, is applied to the semi-static HARQ-ACK codebook, the plurality of HARQ-ACK opportunities may be allocated based on the PDSCH candidate of the last slot to which PDSCH allocation is possible for each bundling group based on each entry of the TDRA table. In addition, the wireless communication system may include a 3GPP NR based wireless communication system.

[0242] Proposal 2: PDSCH candidate-based in all slots

[0243] Proposal 2 is a method of generating a Type-1 HARQ-ACK codebook using PDSCH candidates in all slots. For example, the method of generating a Type-1 HARQ-ACK codebook according to proposal 2 is as follows.

[0244] 1) Step 1: The terminal may include schedulable PDSCH candidate pairs in a set R. Here, the PDSCH candidate pair is a collection of PDSCH candidates that are schedulable by one entry in the TDRA table. Thus, the PDSCH candidate pair represents a PDSCH candidate that may be scheduled for reception in multiple slots. Then, if a symbol of a PDSCH candidate included in a PDSCH candidate pair included in set R overlaps with a symbol configured as UL in a semi-static UL / DL configuration by at least one symbol, the PDSCH candidate is excluded from the PDSCH candidate pair. If all PDSCH candidates are excluded from the PDSCH candidate pair, the PDSCH candidate pair is excluded from set R.

[0245] 2) Two-step: The terminal performs steps A and B for the PDSCH candidate pairs in set R.

[0246] - Step A: Extract one PDSCH candidate pair from the PDSCH candidate pairs in set R. Allocate a new HARQ-ACK opportunity to the PDSCH candidate pair. If there is a PDSCH candidate pair in set R that overlaps with the PDSCH candidate pair for even one symbol, allocate the same HARQ-ACK opportunity to the PDSCH candidate pair. The PDSCH candidate pair to which the HARQ-ACK opportunity is allocated is excluded from set R.

[0247] - Step B: Repeat step A until set R is an empty set.

[0248] Unlike Proposal 1, in Proposal 2, a PDSCH candidate pair corresponds to a HARQ-ACK opportunity. And each PDSCH candidate pair may include a different number of PDSCH candidates. Therefore, the number of PDSCH candidates to be indicated by one HARQ-ACK opportunity may be different. Therefore, the number of PDSCH candidates to be indicated by the HARQ-ACK opportunity may be determined based on the number of the largest number of PDSCH candidates among the PDSCH candidate pairs corresponding to one HARQ-ACK opportunity.

[0249] In step A, the terminal should select one PDSCH candidate pair in set R. To this end, at least the following methods or a combination of the following methods may be considered:

[0250] As a first method, a PDSCH candidate pair including a PDSCH candidate that starts the earliest can be selected, whereby a HARQ-ACK opportunity can be preferentially assigned to the PDSCH candidate that starts the earliest in time.

[0251] As a second method, the PDSCH candidate pair that ends earliest can be selected, so that the HARQ-ACK opportunity can be preferentially assigned to the PDSCH candidate that ends earliest in time.

[0252] As a third method, a PDSCH candidate pair having the fewest symbols can be selected, so that the selected PDSCH candidate pair has minimal overlap with other PDSCH candidate pairs.

[0253] As a fourth method, the PDSCH candidate pair with the most symbols can be selected, so that the selected PDSCH candidate pair can overlap with the most number of PDSCH candidate pairs, and thus a large number of PDSCH candidates can be excluded from the set R.

[0254] As a fifth method, the PDSCH candidate pair with the most slots can be selected. As mentioned above, the number of PDSCH candidates that the HARQ-ACK opportunity should indicate is determined by the number of PDSCH candidates that the PDSCH candidate pair has. Therefore, the PDSCH candidate pair with the most slots can be used as the center to find the PDSCH candidate pair with the least overlap.

[0255] As a sixth method, the PDSCH candidate pair with the lowest index in the TDRA table can be selected, which may be set when the base station sets the TDRA table.

[0256] Time domain bundling

[0257] The terminal may be configured with time domain bundling by the base station when generating a Type-1 HARQ-ACK codebook. Time domain bundling is a method of bundling the HARQ-ACK of each PDSCH into one HARQ-ACK bit (e.g., binary 'AND' operation) and generating the HARQ-ACK as one HARQ-ACK bit (i.e., if the HARQ-ACKs are all ACK, one HARQ-ACK bit is ACK, otherwise one HARQ-ACK bit is NACK) and transmitting it. Here, the PDSCHs to which the time domain bundling is applied may be PDSCHs in the same slot or PDSCHs in different slots. Here, the PDSCHs to which the time domain bundling is applied are PDSCHs scheduled with one DCI and are adjacent PDSCHs when the PDSCHs are aligned in time. For example, when PDSCHs scheduled by one DCI are PDSCH#0 in slot n, PDSCH#1 in slot n+1, PDSCH#2 in slot n+2, and PDSCH#3 in slot n+3, the terminal may bundle the HARQ-ACKs of {PDSCH#0 in slot n, PDSCH#1 in slot n+1} of the four PDSCHs with one HARQ-ACK bit, and bundle the HARQ-ACKs of {PDSCH#2 in slot n+2, PDSCH#3 in slot n+3} with another HARQ-ACK bit. Therefore, four HARQ-ACK bits are generated for the four PDSCHs, but only two HARQ-ACK bits may be transmitted by time domain bundling.

[0258] The terminal may be configured with at least one of the following information from the base station for time domain bundling:

[0259] As the first information, the base station can set the number of HARQ-ACKs (or the number of PDSCHs) to be bundled for time domain bundling. bundle Let us assume that N bundlecan be any one of the values ​​1, 2, 4, or 8. bundle When set, the terminal will bundle The HARQ-ACKs of PDSCHs are bundled and transmitted with one HARQ-ACK bit. Assume that M PDSCHs are scheduled in one DCI. M is N bundle If it is a multiple of (M mod N bundle =0), the terminal is N bundle Each PDSCH is bundled together to generate one bundled HARQ-ACK, and the total bundle However, if M is N bundle If it is not a multiple of (M mod N bundle >0), the terminal may group the PDSCHs as follows: For reference, here, PDSCH#0, PDSCH#1, ..., PDSCH#(M-1) are sorted in time order.

[0260] The first method is to select N bundle PDSCHs are bundled together to generate one bundled HARQ-ACK. If the number of remaining PDSCHs is N bundle If the number of PDSCHs is less than the number of PDSCHs in the group, the remaining PDSCHs are bundled together to generate one bundled HARQ-ACK. bundle {PDSCH#(N -1)} is bundled together to generate one bundled HARQ-ACK. bundle ), PDSCH#(N bundle +1),…,PDSCH#(2*N bundle -1)} to generate one bundled HARQ-ACK. Continue bundling in this way, {PDSCH#(floor(M / N bundle )*N bundle ), PDSCH#(floor(M / N bundle )*N bundle +1),…,PDSCH#(M-1)} to generate one bundled HARQ-ACK. As a result, the total ceil(M / N bundle )bundled HARQ-ACK bits are generated.

[0261] The second method is to group the PDSCHs in time order and use K=ceil(M / N bundle ) groups can be created. The number of PDSCHs included in each group can be ceil(M / K) or floor(M / K). Ceil(M / K) PDSCHs can be grouped in time order to create M mod K groups, and then floor(M / K) PDSCHs can be grouped in time order to create K-(M mod K) groups. The HARQ-ACKs in the group can be bundled to generate one bundled HARQ-ACK, resulting in a total of ceil(M / N bundle )bundled HARQ-ACK bits are generated.

[0262] As the second information, the base station can set the number of bundled HARQ-ACKs (or the number of PDSCHs / bundling groups) for time domain bundling. group Let us assume that N group can be any one of the values ​​1, 2, 4, or 8. group When this is set, the terminal aggregates M PDSCHs into N group PDSCH groups can be created. For reference, if M is N group If it is smaller than , one PDSCH is grouped together to create M PDSCH groups, and the next N group -M groups do not include a PDSCH. The HARQ-ACK of a group that does not include a PDSCH may be set to NACK. The HARQ-ACK of a group that does not include a PDSCH may not be transmitted to the base station.

[0263] The first method is to use K=ceil(M / N group) PDSCHs can be bundled together to generate one bundled HARQ-ACK. If the number of remaining PDSCHs is less than K, the remaining PDSCHs can be bundled together to generate one bundled HARQ-ACK. For example, {PDSCH#0, PDSCH#1, ..., PDSCH#(K-1)} can be bundled together to generate one bundled HARQ-ACK, and {PDSCH#(K), PDSCH#(K+1), ..., PDSCH#(2*K-1)} can be bundled together to generate one bundled HARQ-ACK. By continuing to bundle together in this manner, {PDSCH#(floor(M / K)*K), PDSCH#(floor(M / K)*K+1), ..., PDSCH#(M-1)} can be bundled together to generate one bundled HARQ-ACK. As a result, a total of N group A bundled HARQ-ACK bit may be generated.

[0264] As the second method, PDSCHs are grouped in time order and N group groups can be created. The number of PDSCHs in each group is ceil(M / N group ) or floor(M / N group ) in chronological order. group ) PDSCHs are combined into M mod N group Then, in chronological order, floor(M / N group ) PDSCHs are collectively expressed as N group -(M mod N group ) groups. HARQ-ACKs in a group can be bundled to generate one bundled HARQ-ACK, resulting in a total of N group A bundled HARQ-ACK bit is generated.

[0265] As the third information, the base station can set a time interval for time domain bundling. The time interval can be set in slot units. The time interval can be called a bundling window. The time interval set in slot units is defined as N slot Let us assume that the terminal is N slotThe PDSCHs included in the slots can be grouped together to form one group. If there is at least one PDSCH included in the group, the terminal can bundle the HARQ-ACKs of the PDSCHs into one HARQ-ACK. The HARQ-ACK of a group that does not include a PDSCH may be set to NACK. Also, the HARQ-ACK of a group that does not include a PDSCH may not be transmitted to the base station. The terminal slot The slots can be determined as follows:

[0266] In the first method, the terminal selects consecutive N slots starting from slot 0 of the frame. slot For each slot, the PDSCHs contained in that slot can be grouped together. That is, for slot i*N slot , slot i*N slot +1, …, slot(i+1)*N slot PDSCHs included in i can be grouped together, where i is an integer.

[0267] In the second method, the terminal selects N consecutive slots starting from slot k of the frame. slot For each slot, the PDSCHs contained in that slot can be grouped together. That is, for slot i*N slot +k, slot i*N slot +k+1, …., slot(i+1)*N slot PDSCHs included in slots 0, 1, ..., k-1 can be grouped together. Here, i is an integer. Here, k may be a value set by the base station in the terminal, a value determined based on an index of a slot in which the first PDSCH is scheduled, a value determined based on an index of a slot in which a PDCCH scheduling the PDSCH is transmitted, or a value determined based on an index of a slot in which a PUCCH including a HARQ-ACK of the PDSCH is transmitted. k is an integer and corresponds to a slot offset.

[0268] For example, k may be X, where X is a value determined based on the index of the slot in which the first PDSCH is scheduled. Since the first PDSCH is scheduled in slot 3, k is determined from slots 3 to N. slot = 4 slots, i.e., the PDSCHs included in slots 3, 4, 5, and 6 are grouped together, and the next N slot = 4 slots, i.e., PDSCHs included in slot 7, slot 8, slot 9, and slot 10 can be grouped together into one group. k is an integer and corresponds to the slot offset.

[0269] For example, k may be X, where X is a value determined based on the index of a slot in which a PDCCH that schedules a PDSCH is transmitted. Since a PDCCH is scheduled in slot 1, k is determined based on the index of a slot in which a PDCCH that schedules a PDSCH is transmitted. slot = The PDSCHs contained in four slots, i.e., slot 1, slot 2, slot 3, and slot 4, are grouped together and the next N slot =Four slots can be grouped together: slot 5, slot 6, slot 7, and slot 8.

[0270] For example, if the index of the slot in which the PUCCH including the HARQ-ACK of the PDSCH is transmitted is X, then k = X mod N slot Since PUCCH is scheduled in slot 10, k=10 mod 4=2. Therefore, from slot 2 to N slot = 4 slots, i.e., the PDSCHs contained in slots 2, 3, 4, and 5 are grouped together, and the next N slot =Four slots can be grouped together: slot 6, slot 7, slot 8, and slot 9.

[0271] Refer to Figure 21. slotAssume that k=3 is set, where k=n-5. That is, a bundling window may be set by bundling three slots starting from slot n-5. For example, slot n-5, slot n-4, and slot n-3 may be included in bundling window #A, and slot n-2, slot n-1, and slot n may be included in bundling window #B. Therefore, the PDSCHs included in bundling window #A may be bundled to generate one bundled HARQ-ACK bit, and the PDSCHs included in bundling window #B may be bundled to generate one bundled HARQ-ACK bit.

[0272] Hereinafter, a method for a terminal to generate a Type-1 HARQ-ACK codebook when time domain bundling is configured will be described. For the sake of explanation, it is assumed in the present invention that the terminal generates a group that aggregates PDSCHs based on the first information, the second information, or the third information. For convenience, the PDSCHs included in each group are represented as {PDSCH#n, PDSCH#(n+1),..., PDSCH#(n+k-1)}. The number of PDSCHs included in each group is k.

[0273] In the present invention, a terminal may select one of the PDSCHs included in a group as a representative. In this case, the terminal may generate a Type-1 HARQ-ACK codebook based on the SLIV corresponding to the PDSCH. A method of selecting one of the PDSCHs included in a group as a representative may include at least one of the following.

[0274] As a first method, among the PDSCHs included in the group, the earliest PDSCH in time (e.g., the first slot) can be selected as the representative. For example, if the PDSCHs included in the group are {PDSCH#n, PDSCH#(n+1),...,PDSCH#(n+k-1)}, PDSCH#n can be selected as the representative.

[0275] As a second method, the latest PDSCH (e.g., the last slot) among the PDSCHs included in the group can be selected as the representative. For example, if the PDSCHs included in the group are {PDSCH#n, PDSCH#(n+1),...,PDSCH#(n+k-1)}, PDSCH#(n+k-1) can be selected as the representative.

[0276] As a third method, among the PDSCHs included in the group, the PDSCH that occupies the most symbols can be selected as a representative. If multiple PDSCHs occupy the same number of symbols, the earliest PDSCH or the latest PDSCH in time can be selected as a representative.

[0277] As a fourth method, among the PDSCHs included in the group, the PDSCH occupying the fewest symbols can be selected as a representative. If multiple PDSCHs occupy the same number of symbols, the earliest PDSCH or the latest PDSCH in time can be selected as a representative.

[0278] As a fifth method, in the first, second, third and fourth methods, among the PDSCHs, a PDSCH having at least one symbol overlapping with a symbol configured as an UL by a semi-static UL / DL configuration may be excluded.

[0279] Referring to FIG. 22, the terminal is informed of N by the second information. slotAssume that k=3 is set. Here, k=n-5. That is, a bundling window may be set for every three slots starting from slot n-5. For example, slot n-5, slot n-4, and slot n-3 may be included in bundling window #A, and slot n-2, slot n-1, and slot n may be included in bundling window #B. The terminal may select the latest PDSCH candidate in time as a representative PDSCH (representative SLIV) among the PDSCH candidates in the bundling window. For example, when K1 value is 2 and TDRA index (or entry)=3, four PDSCH candidates may be scheduled in slot n-5, slot n-4, slot n-3, and slot n-2. Of these, the first three PDSCH candidates (PDSCH candidates scheduled in slot n-5, slot n-4, and slot n-3) belong to bundling window #A. Therefore, the PDSCH candidate of slot n-3, which is the latest PDSCH candidate in time, among the PDSCH candidates, can be selected as a representative PDSCH (representative SLIV). And, one PDSCH candidate (i.e., the PDSCH candidate scheduled in slot n-2) belongs to bundling window #B. Therefore, the PDSCH candidate of slot n-2, which is the latest PDSCH candidate in time, among the PDSCH candidates, can be selected as a representative PDSCH (representative SLIV). The representative PDSCH (representative SLIV) selected in this way is shown in FIG.

[0280] In the following description, the selected PDSCH (corresponding SLIV) is called a representative PDSCH (or a representative SLIV). A representative PDSCH (or a representative SLIV) is determined for each group. The terminal can generate a Type-1 HARQ-ACK codebook based on the representative SLIV as follows.

[0281] 1) Step 1: A set of K1 values ​​that can be instructed to the terminal is defined as K1_set. Based on K1_set and the TDRA table, the terminal can determine the index of the slot in which the representative PDSCH candidate (representative SLIV candidate) is received. In this case, the set of indexes of the slot in which the representative PDSCH candidate (representative SLIV candidate) is received is defined as K_slot.

[0282] 2) Step 2: Extract the maximum K1 value (K1_max) in K_slot. Then, the K1_max value is excluded from K_slot.

[0283] 3) Step 3: Let R be a set of representative PDSCH candidates (or representative SLIV candidates) receivable in slot n-K1_max. If at least one symbol of a representative PDSCH candidate (or representative SLIV candidate) included in set R overlaps with a symbol configured as UL in the semi-static UL / DL configuration, the representative PDSCH candidate (representative SLIV candidate) is excluded from set R.

[0284] The representative PDSCH candidate (or the representative SLIV candidate) included in the set R can be obtained as follows. One K1 value can be selected from K1_set. Let the selected K1 value be K1_a. Based on the K1_a value and the TDRA table, the terminal can determine the representative PDSCH candidate (or the representative SLIV candidate) in slot n-K1_max.

[0285] 4) Step 4: The terminal performs steps A and B for the representative PDSCH candidates (or representative SLIV candidates) included in set R.

[0286] - Step A: A new HARQ-ACK opportunity is assigned to the representative PDSCH candidate (representative SLIV candidate) whose last symbol is the earliest among the representative PDSCH candidates (representative SLIV candidates) in set R. Then, if there is a representative PDSCH candidate (representative SLIV candidate) in set R whose last symbol overlaps with the representative PDSCH candidate (representative SLIV candidate) whose last symbol is the earliest by even one symbol, the same HARQ-ACK opportunity is assigned to the representative PDSCH candidate (representative SLIV candidate). The representative PDSCH candidate (representative SLIV candidate) to which the HARQ-ACK opportunity is assigned (i.e., (i) the representative PDSCH candidate (representative SLIV candidate) whose last symbol is the earliest and (ii) the representative PDSCH candidate (representative SLIV candidate) that overlaps with the representative PDSCH candidate (representative SLIV candidate) by at least one symbol) is excluded from set R.

[0287] - Step B: Repeat step A until set R is an empty set.

[0288] 5) 5th step: Repeat steps 2 / 3 / 4 until K_slot becomes an empty set.

[0289] 6) Sixth stage: The terminal can allocate B HARQ-ACK bits to representative PDSCH candidates (or representative SLIV candidates) to which the same HARQ-ACK opportunity is allocated, where B is the maximum number of PDSCHs included in a group including representative PDSCH candidates (or representative SLIV candidates) to which the same HARQ-ACK opportunity is allocated.

[0290] This will be described in more detail with reference to Fig. 23. First, it is assumed that the terminal has determined the representative PDSCH candidates (representative SLIV candidates) according to Fig. 22.

[0291] 1) Stage 1: The K1 values ​​for the terminal are set to 1 and 2, so K1_set={1,2}. When the K1 value is 2, the representative PDSCH candidate (or the representative SLIV candidate) is located in slot n-3 and slot n-2. Therefore, the K1 values ​​for the slots are 3 and 2. These two values ​​may be included in K_slot. Also, when the K1 value is 1, the representative PDSCH candidate (or the representative SLIV candidate) is located in slot n-3 and slot n-1. Therefore, the K1 values ​​for the slots are 3 and 1. The two values ​​may be included in K_slot. Therefore, when K1_set={1,2} is set, K_slot is {1,2,3} as the union of the two.

[0292] 2) Step 2: Select the maximum value K1_max=3 from K_slot. Then, the K1_max value is excluded from K_slot.

[0293] 3) Step 3: Let R be a set of representative PDSCH candidates (or representative SLIV candidates) receivable in slot n-K1_max=n-3. If at least one symbol of a representative PDSCH candidate (or representative SLIV candidate) included in set R overlaps with a symbol configured as UL in the semi-static UL / DL configuration, the representative PDSCH candidate (or representative SLIV candidate) is excluded from set R. For ease of explanation, it is assumed in this example that all symbols in a slot are downlink symbols.

[0294] Representative PDSCH candidates (or representative SLIV candidates) included in set R in slot n-3 are R={(S=0, L=14), (S=0, L=7), (S=7, L=7)}.

[0295] 4) Step 4: The terminal performs steps A and B for the representative PDSCH candidates (representative SLIV candidates) included in R.

[0296] - Step A: Among the representative PDSCH candidates in set R, the representative PDSCH candidate (representative SLIV candidate) (S=0, L=7) whose last symbol is the earliest is assigned HARQ-ACK opportunity 0. Then, the same HARQ-ACK opportunity is assigned to the representative PDSCH candidate (representative SLIV candidate) (S=0, L=14) whose last symbol overlaps with the representative PDSCH candidate (representative SLIV candidate) (S=0, L=7) whose last symbol is the earliest in set R. The representative PDSCH candidates (representative SLIV candidates) (S=0, L=7) and (S=0, L=14) to which the HARQ-ACK opportunity is assigned are excluded from set R. Therefore, set R={(S=7, L=7)}.

[0297] - Step B: Repeat step A until set R becomes an empty set. In this example, set R is not an empty set, so repeat step A. Step A assigns HARQ-ACK opportunity 1 to the representative PDSCH candidate (or representative SLIV candidate) (S=7, L=7), and set R becomes an empty set. This completes the 4th stage.

[0298] 5) 5th step: Repeat 2 / 3 / 4 steps until K_slot is an empty set. In the example, K_slot={2,1}, so it is not an empty set. Since K_slot is not an empty set, repeat 2 / 3 / 4 steps.

[0299] Through the above steps, PDSCH candidates and HARQ-ACK opportunities are determined as follows.

[0300] HARQ-ACK opportunity 0: Representative PDSCH candidate for slot n-3 (S=0, L=7), (S=0, L=14)

[0301] HARQ-ACK opportunity 1: Representative PDSCH candidate for slot n-3 (S=7, L=7)

[0302] HARQ-ACK opportunity 2: Representative PDSCH candidate for slot n-2 (S=0, L=7), (S=0, L=14)

[0303] HARQ-ACK opportunity 3: Representative PDSCH candidate for slot n-2 (S=7, L=7)

[0304] HARQ-ACK opportunity 4: Representative PDSCH candidate for slot n-1 (S=0, L=7), (S=0, L=14)

[0305] HARQ-ACK opportunity 5: Representative PDSCH candidate for slot n-1 (S=7, L=7)

[0306] Therefore, the Type-1 HARQ-ACK codebook may consist of 6 HARQ-ACK opportunities.

[0307] 6) Step 6: The terminal can determine the number of HARQ-ACK bits per HARQ-ACK opportunity as follows: The representative PDSCH candidates included in HARQ-ACK opportunity 0 are (S=0, L=7), (S=0, L=14), and the TDRA index (or entry) to which the representative PDSCH candidates belong in the bundling window is 0, 1, 3, 4, 6, 7, 8, 9 when K1=2, and 3, 4 when K1=1. Among these, when K1=2 and the TDRA index is 3, there are the most three PDSCH candidates in the bundling window, so HARQ-ACK opportunity 0 includes three HARQ-ACK bits. In a similar manner, HARQ-ACK Opportunity 1 may include three HARQ-ACK bits, HARQ-ACK Opportunity 2 may include one HARQ-ACK bit, HARQ-ACK Opportunity 3 may include one HARQ-ACK bit, HARQ-ACK Opportunity 4 may include two HARQ-ACK bits, and HARQ-ACK Opportunity 5 may include two HARQ-ACK bits.

[0308] Therefore, the Type-1 HARQ-ACK codebook may include a total of 12 HARQ-ACK bits.

[0309] Type-2 (or Dynamic) HARQ-ACK Codebook

[0310] A dynamic HARQ-ACK codebook may be configured in the terminal. When the dynamic HARQ-ACK codebook is used, the base station may signal information required for HARQ-ACK codebook generation by the PDCCH (or DCI). Specifically, the base station may signal information required for HARQ-ACK codebook generation by a DAI (Downlink Assignment Index) field of the PDCCH (or DCI). Specifically, the DAI may indicate i) the number of bits of the HARQ-ACK codebook, and / or ii) information regarding the position of the HARQ-ACK bit corresponding to the DAI in the HARQ-ACK codebook. Here, the HARQ-ACK bit corresponding to the DAI may (i) mean a HARQ-ACK bit for a PDSCH scheduled by the DAI, or (ii) mean a HARQ-ACK bit for the DAI. The DAI may be divided into a counter-DAI and a total-DAI. The terminal may determine the number of bits of the dynamic HARQ-ACK codebook based on the DAI of the PDCCH (or DCI).

[0311] Meanwhile, the Type-2 HARQ-ACK codebook may be composed of two sub-codebooks. Information required for configuring each sub-codebook (e.g., sub-codebook size (e.g., number of bits), HARQ-ACK bit position in the sub-codebook) may be obtained based on DAI information in each DCI.

[0312] The first sub-codebook includes HARQ-ACK bits of PDSCH by TB-based transmission. Here, PDSCH is scheduled by each DCI. That is, one PDSCH is scheduled by one DCI (hereinafter, single PDSCH scheduling). Also, if PDSCH by TB-based transmission is configured to include one TB, one HARQ-ACK bit may be generated per PDSCH, and if it is configured to include two TBs in at least one cell (and spatial bundling is not configured), two HARQ-ACK bits may be generated per PDSCH. Therefore, (when spatial bundling is not configured), P HARQ-ACK bits may be generated per DCI that schedules TB-based transmission. Here, P is the maximum number of TBs included in PDSCH. For reference, if the number of TBs scheduled in DCI is less than P, HARQ-ACK bits corresponding to the missing number of TBs (i.e., TBs that are not scheduled) are set as NACK.

[0313] The second sub-codebook includes HARQ-ACK bits of PDSCH by CBG (code block group) based transmission. The terminal determines that the PDSCH by CBG based transmission in cell c is (at most) N CBG,c For all cells configured for CBG-based transmission, ((maximum) number of TBs in cell c)*N CBG,c The maximum value of N CBG,max The terminal schedules the CBG-based transmission for N DCIs. CBG,max Generates HARQ-ACK bits. For reference, the number of CBGs scheduled in DCI is N CBG,max If the number is less than the number of CBGs, the HARQ-ACK bits corresponding to the missing number of CBGs are set to NACK.

[0314] Hereinafter, a method of generating a Type-2 HARQ-ACK (sub) codebook when multiple PDSCHs are scheduled in one DCI (i.e., multi-slot scheduling; multi-PDSCH scheduling) will be described. For convenience of explanation, in the following description, it is described that the second sub-codebook includes both the CBG-based HARQ-ACK bit and the multi-PDSCH scheduling-based HARQ-ACK bit. However, this is merely an example, and in an actual wireless communication environment, the second sub-codebook may only include the multi-PDSCH scheduling-based HARQ-ACK bit according to the scheduling situation. As a first method, when multiple PDSCHs are scheduled in one DCI, the terminal may always transmit the HARQ-ACK of the multi-PDSCH using the second sub-codebook. Here, the second sub-codebook may be modified as follows.

[0315] The second sub-codebook includes (i) a HARQ-ACK bit of a PDSCH by CBG-based transmission, and (ii) a HARQ-ACK bit of the multiple PDSCHs when multiple PDSCHs are scheduled in one DCI. CBG,c For all cells configured for CBG-based transmission, ((maximum) number of TBs in cell c)*N CBG,c The maximum value of N CBG,max In addition, when multiple PDSCHs are scheduled in one DCI, the maximum number of PDSCHs scheduled by one TDRA index is set to N multi-PDSCH,max Let's say.

[0316] The terminal shall transmit CBG-based transmissions with a maximum of max(N CBG,max ,N multi-PDSCH,max ) HARQ-ACK bits. The terminal can generate max(N CBG,max ,N multi-PDSCH,max) HARQ-ACK bits. If the number of CBGs scheduled in the DCI is max(N CBG,max ,N multi-PDSCH,max ), the HARQ-ACK bits corresponding to the missing (CBG) number are set to NACK. CBG,max ,N multi-PDSCH,max ), the HARQ-ACK bits corresponding to the missing number of (PDSCHs) are set to NACK.

[0317] As a second method, when multiple PDSCHs are scheduled in one DCI for a terminal, the HARQ-ACK of the multi-PDSCH may be selectively transmitted by the first sub-codebook or the second sub-codebook according to the number of PDSCHs, where the first sub-codebook and the second sub-codebook may be modified as follows:

[0318] The first sub-codebook may include (i) a HARQ-ACK bit of a PDSCH by TB-based transmission, and (ii) a HARQ-ACK bit of a PDSCH when multiple PDSCHs are scheduled in one DCI (i.e., multi-PDSCH), if the number of PDSCHs is X or less. Assume that a PDSCH by TB-based transmission is configured to include P TBs, where P is the maximum number of TBs included in a PDSCH. Thus, max{P,X} HARQ-ACK bits may be generated per DCI that schedules a TB-based transmission. For reference, if the number of TBs scheduled in a DCI is less than max{P,X}, the HARQ-ACK bits corresponding to the missing (PDSCH) number are set to NACK. For reference, a DCI that indicates multi-PDSCH scheduling schedules X or less PDSCHs. If the number of PDSCHs scheduled by DCI indicating multi-PDSCH scheduling is less than max{P,X}, the HARQ-ACK bits corresponding to the missing (PDSCH) number are set to NACK.

[0319] The second sub-codebook includes (i) a HARQ-ACK bit of a PDSCH by CBG-based transmission, and (ii) a HARQ-ACK bit of the multiple PDSCHs when multiple PDSCHs are scheduled in DCI and the number of the PDSCHs exceeds X. The terminal determines whether the PDSCH by CBG-based transmission for cell c is (at most) N per TB. CBG,c For all cells configured for CBG-based transmission, ((maximum) number of TBs in cell c)*N CBG,c The maximum value of N CBG,max When multiple PDSCHs are scheduled in DCI, the maximum number of PDSCHs scheduled by one TDRA index is N multi-PDSCH,max For reference, let's say N multi-PDSCH,max is greater than X.

[0320] The terminal shall transmit CBG-based transmissions with a maximum of max(N CBG,max ,N multi-PDSCH,max ) HARQ-ACK bits. The terminal generates max(N CBG,max ,N multi-PDSCH,max ) HARQ-ACK bit. The number of CBGs scheduled by DCI is max(N CBG,max ,N multi-PDSCH,max ), the HARQ-ACK bits corresponding to the missing (CBG) number are set to NACK. CBG,max ,N multi-PDSCH,max ), the HARQ-ACK bits corresponding to the missing number of (PDSCHs) are set to NACK.

[0321] In the above, it may be preferably determined that X=P, that is, if the multi-PDSCH scheduling DCI schedules less than or equal to P PDSCHs, the HARQ-ACK of the multi-PDSCHs is included in the first sub-codebook, and if the multi-PDSCH scheduling DCI schedules more than P PDSCHs, the HARQ-ACK of the multi-PDSCHs is included in the second sub-codebook.

[0322] The second method may be modified as follows when the Type-2 HARQ-ACK codebook and time domain bundling are configured simultaneously: Time domain bundling is as described above.

[0323] As a second modified method, when multiple PDSCHs are scheduled in one DCI for a terminal, the HARQ-ACK of the multi-PDSCHs may be selectively transmitted by the first sub-codebook or the second sub-codebook according to the number of bundled HARQ-ACK bits according to the DCI. The number of bundled HARQ-ACK bits is determined by the number of PDSCHs / bundling groups. Here, the first sub-codebook and the second sub-codebook may be modified as follows:

[0324] The first sub-codebook includes (i) HARQ-ACK bits of PDSCH by TB-based transmission, and (ii) bundled HARQ-ACK bits by DCI if bundled HARQ-ACK by DCI is X bits or less when multiple PDSCHs are scheduled in one DCI. Assume that PDSCH by TB-based transmission is set to include (maximum) P TBs, where P is the maximum number of TBs included in PDSCH. Therefore, max{P,X} HARQ-ACK bits may be generated for each DCI that schedules TB-based transmission. For reference, if the number of TBs scheduled in DCI is less than max{P,X}, HARQ-ACK bits corresponding to the missing (TB) number are set as NACK. For reference, max{P,X} bundled HARQ-ACK bits may be generated for each DCI that schedules TB-based transmission. For reference, DCI that indicates multi-PDSCH scheduling corresponds to bundled HARQ-ACK bits of X bits or less. If the number of bundled HARQ-ACK bits corresponding to DCI indicating multi-PDSCH scheduling is less than max{P,X}, the bundled HARQ-ACK bits corresponding to the missing (PDSCH) number are set to NACK.

[0325] The second sub-codebook includes (i) HARQ-ACK of PDSCH by CBG-based transmission, and (ii) when multiple PDSCHs are scheduled in DCI, if the bundled HARQ-ACK by DCI exceeds X bits, the bundled HARQ-ACK bits are included. CBG,c For all cells configured for CBG-based transmission, ((maximum) number of TBs in cell c)*N CBG,c The maximum value of N CBG,max When multiple PDSCHs are scheduled in DCI, the maximum number of bundled HARQ-ACK bits corresponding to one TDRA index is set as N bundled,max For reference, let's say Nbundled,max is a value greater than X.

[0326] The terminal may set max(N CBG,max ,N bundled,max ) HARQ-ACK bits. The terminal can generate max(N CBG,max ,N bundled,max ) HARQ-ACK bit. If the number of CBGs scheduled in the DCI is max(N CBG,max ,N bundled,max ), the HARQ-ACK bits corresponding to the missing (CBG) number are set to NACK. CBG,max ,N bundled,max ), the bundled HARQ-ACK bits corresponding to the missing number are set to NACK.

[0327] For example, assume that a terminal always generates one bundled HARQ-ACK bit for a DCI indicating multi-PDSCH scheduling. For example, this corresponds to the case where the number of PDSCHs / bundling groups for time domain bundling is set to one. In this case, the bundled HARQ-ACK bit may be included in the first sub-codebook (e.g., X=1). In other cases (e.g., when the number of PDSCHs / bundling groups for time domain bundling is multiple), the bundled HARQ-ACK bit may be included in the second sub-codebook.

[0328] FIG. 24 illustrates a HARQ-ACK codebook transmission process according to an embodiment of the present invention.

[0329] Referring to FIG. 24, a terminal may receive single-PDSCH scheduling (S2402). Also, the terminal may receive multi-PDSCH scheduling (S2404). Here, it is assumed that TB-based HARQ-ACK feedback is applied to the single / multi-PDSCH scheduling, respectively. The terminal may generate and transmit a Type-2 HARQ-ACK codebook including HARQ-ACK information for the single / multi-PDSCH scheduling (S2406). The Type-2 HARQ-ACK codebook may include a first sub-codebook and may further include a second sub-codebook.

[0330] Here, the first sub-codebook includes TB-based HARQ-ACK information for single-PDSCH scheduling. The TB-based HARQ-ACK information for multi-PDSCH scheduling may be included in the first sub-codebook or configured in the second sub-codebook depending on the number of bundled HARQ-ACK bits. For example, if the number of PDSCHs / bundling groups for multi-PDSCH scheduling is less than or equal to X (e.g., X=1), the TB-based HARQ-ACK information for multi-PDSCH scheduling may be included in the first sub-codebook. On the other hand, if the number of PDSCHs / bundling groups for multi-PDSCH scheduling is more than X (e.g., X=1), the TB-based HARQ-ACK information for multi-PDSCH scheduling may be configured in the second sub-codebook. The second sub-codebook is concatenated after the first sub-codebook.

[0331] FIG. 25 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention. In an embodiment of the present invention, the terminal is embodied as various types of wireless communication devices or computing devices that ensure portability and mobility. The terminal is referred to as a UE, a Station (STA), a Mobile Subscriber (MS), etc. In addition, in an embodiment of the present invention, the base station controls and manages cells (e.g., macrocells, femtocells, picocells, etc.) corresponding to a service area, and performs functions such as signal transmission, channel assignment, channel monitoring, self-diagnosis, and relaying. The base station is referred to as a next generation NodeB (gNB) or an Access Point (AP), etc.

[0332] As shown, a terminal 100 according to one embodiment of the present invention includes a processor 110 , a communication module 120 , a memory 130 , a user interface unit 140 , and a display unit 150 .

[0333] First, the processor 110 executes various commands or programs to process data within the terminal 100. The processor 110 also controls the overall operation of the terminal 100 including each unit, and controls the transmission and reception of data between the units. Here, the processor 110 is configured to perform operations according to the embodiments described in the present invention. For example, the processor 110 may receive slot configuration information, determine the slot configuration based thereon, and perform communication according to the determined slot configuration.

[0334] Next, the communication module 120 is an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. For this purpose, the communication module 120 includes a plurality of network interface cards (NICs) such as cellular communication interface cards 121 and 122 and an unlicensed band communication interface card 123, either built-in or external. In the drawings, the communication module 120 is shown as an integrated module, but the network interface cards may be arranged independently depending on the circuit configuration or application, unlike the drawings.

[0335] The cellular communication interface card 121 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server via the mobile communication network, and provides a cellular communication service in a first frequency band based on instructions from the processor 110. According to an embodiment, the cellular communication interface card 121 includes at least one NIC module that utilizes a frequency band below 6 GHz. The at least one NIC module of the cellular communication interface card 121 independently performs cellular communication with at least one of the base station 200, the external device, and the server according to a cellular communication standard or protocol of the frequency band below 6 GHz supported by the NIC module.

[0336] The cellular communication interface card 122 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server using a mobile communication network, and provides a cellular communication service in the second frequency band based on instructions from the processor 110. According to an embodiment, the cellular communication interface card 122 includes at least one NIC module that utilizes a frequency band of 6 GHz or higher. The at least one NIC module of the cellular communication interface card 122 independently performs cellular communication with at least one of the base station 200, the external device, and the server according to a cellular communication standard or protocol of the 6 GHz or higher frequency band supported by the NIC module.

[0337] The unlicensed band communication interface card 123 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server through the third frequency band, which is an unlicensed band, and provides communication services in the unlicensed band based on instructions from the processor 110. The unlicensed band communication interface card 123 includes at least one NIC module that utilizes the unlicensed band. For example, the unlicensed band may be a 2.4 GHz or 52.6 GHz band. The at least one NIC module of the unlicensed band communication interface card 123 performs cellular communication with at least one of the base station 200, the external device, and the server, independently or dependently, according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0338] The memory 130 stores control programs and various data used by the terminal 100. The control programs include predetermined programs required for the terminal 100 to perform wireless communication with at least one of the base station 200, an external device, and a server.

[0339] Next, the user interface 140 includes various types of input / output means provided in the terminal 100. That is, the user interface unit 140 receives user input using various input means, and the processor 110 controls the terminal 100 based on the received user input. Also, the user interface 140 performs output based on a command from the processor 110 using various output means.

[0340] Then, the display unit 150 outputs various images on a display screen. The display unit 150 outputs various display objects, such as a user interface, based on the contents performed by the processor 110 or a control command of the processor 110.

[0341] The base station 200 according to the embodiment of the present invention also includes a processor 210 , a communication module 220 , and a memory 230 .

[0342] First, the processor 210 executes various commands or programs to process data within the base station 200. The processor 210 also controls the overall operation of the base station 200 including each unit, and controls transmission and reception of data between the units. Here, the processor 210 is configured to perform operations according to the embodiments described in the present invention. For example, the processor 210 may signal slot configuration information and perform communication according to the signaled slot configuration.

[0343] Next, the communication module 220 is an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. For this purpose, the communication module 220 includes a plurality of network interface cards, such as cellular communication interface cards 221 and 222 and an unlicensed band communication interface card 223, either built-in or external. In the drawings, the communication module 220 is shown as an integrated module, but the respective network interface cards may be arranged independently depending on the circuit configuration or application, unlike the drawings.

[0344] The cellular communication interface card 221 transmits and receives wireless signals to and from at least one of the terminal 100, the external device, and the server using a mobile communication network, and provides a cellular communication service in a first frequency band according to an instruction of the processor 210. According to an embodiment, the cellular communication interface card 221 includes at least one NIC module that uses a frequency band below 6 GHz. The at least one NIC module of the cellular communication interface card 221 independently performs cellular communication with at least one of the terminal 100, the external device, and the server according to a cellular communication standard or protocol of the frequency band below 6 GHz supported by the NIC module.

[0345] The cellular communication interface card 222 transmits and receives wireless signals to and from at least one of the terminal 100, an external device, and a server using a mobile communication network, and provides a cellular communication service in the second frequency band based on instructions from the processor 210. According to an embodiment, the cellular communication interface card 222 includes at least one NIC module that uses a frequency band of 6 GHz or higher. The at least one NIC module of the cellular communication interface card 222 independently performs cellular communication with at least one of the terminal 100, an external device, and a server according to a cellular communication standard or protocol of the 6 GHz or higher frequency band supported by the NIC module.

[0346] The unlicensed band communication interface card 223 transmits and receives wireless signals to and from at least one of the terminal 100, the external device, and the server using the third frequency band, which is an unlicensed band, and provides communication services in the unlicensed band based on instructions from the processor 210. The unlicensed band communication interface card 223 includes at least one NIC module that uses the unlicensed band. For example, the unlicensed band may be a 2.4 GHz or 52.6 GHz band. The at least one NIC module of the unlicensed band communication interface card 223 performs cellular communication with at least one of the terminal 100, the external device, and the server, independently or dependently, according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0347] The terminal 100 and base station 200 shown in FIG. 25 are block diagrams according to an embodiment of the present invention, and the separated blocks are used to logically distinguish the elements of the devices. Thus, the above-mentioned device elements may be mounted on one chip or multiple chips depending on the design of the device. Also, some components of the terminal 100, such as the user interface 150 and the display unit 150, may be selectively provided in the terminal 100. Also, the user interface 140 and the display unit 150 may be additionally provided in the base station 200 as necessary.

[0348] The above description of the present invention is for illustrative purposes only, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all respects and are not limiting. For example, each component described as a single form may be implemented in a distributed form, and each component described as a distributed form may be implemented in a combined form.

[0349] The scope of the present invention is indicated by the claims set forth below rather than by the above detailed description, and all modifications and variations derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. [Industrial Applicability]

[0350] The present invention is applicable to a wireless communication system, and more particularly, to a communication method and an apparatus therefor used in a wireless communication system. [Explanation of symbols]

[0351] 100 devices 110 Processor 120 Communication Module 130 Memory 140 User Interface Section 150 display units 200 base stations 210 Processor 220 Communication Module 230 Memory

Claims

1. A terminal for use in a wireless communication system, A communication module; A processor for controlling the communication module, the processor comprising: A physical downlink control channel (PDCCH) having information is received, the information being Index information indicating an entry in a time-domain resource allocation (TDRA) table for a physical downlink shared channel (PDSCH) allocation; and K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 ｉ } (i=1, 2, . . . ), If the timing information indicates slot n, then for all K1 values ​​in the K1 set, slot n-K1 ｉ determining PDSCH candidates; and transmit a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot; When determining the PDSCH candidate, the K1 set is replaced with a union of K sets #i based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values; The K set #i: {K1 ｉ +d １ , K1 ｉ +d ２ ,...,K1 ｉ +d Ｎ }、 Here, d ｋ (k=1, 2, . . . , N) corresponds to the slot index difference between the last slot for which PDSCH allocation is possible and the kth slot for which PDSCH allocation is possible based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

2. The terminal of claim 1, wherein a subcarrier spacing (SCS) applied to a slot for transmitting the PDCCH is the same as a SCS applied to a slot for transmitting the semi-static HARQ-ACK codebook.

3. The terminal of claim 1, wherein for the determined PDSCH candidates for each slot, multiple HARQ-ACK opportunities are sequentially assigned to PDSCH candidates whose last symbol does not overlap with the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook is configured based on the multiple HARQ-ACK opportunities.

4. 4. The terminal of claim 3, wherein when time domain bundling is applied to the semi-static HARQ-ACK codebook, the multiple HARQ-ACK opportunities are allocated based on the PDSCH candidate of the last slot in which PDSCH allocation is possible for each bundling group based on each entry of the TDRA table.

5. The terminal of claim 1 , wherein the wireless communication system comprises a 3rd generation partnership project (3GPP) new radio (NR) based wireless communication system.

6. 1. A method for use by a terminal in a wireless communication system, comprising: receiving a physical downlink control channel (PDCCH) having information, the information comprising: Index information indicating an entry in a time-domain resource allocation (TDRA) table for a physical downlink shared channel (PDSCH) allocation; and K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 ｉ } (i=1, 2, . . . ), If the timing information indicates slot n, then for all K1 values ​​in the K1 set, slot n-K1 ｉ determining PDSCH candidates; and transmitting a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot; When determining the PDSCH candidate, the K1 set is replaced with a union of K sets #i based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values; The K set #i: {K1 ｉ +d １ , K1 ｉ +d ２ ,...,K1 ｉ +d Ｎ }、 Here, d ｋ (k=1, 2, . . . , N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

7. The method of claim 6, wherein a subcarrier spacing (SCS) applied to a slot for transmitting the PDCCH is the same as a SCS applied to a slot for transmitting the semi-static HARQ-ACK codebook.

8. 7. The method of claim 6, wherein for the determined PDSCH candidates for each slot, multiple HARQ-ACK occasions are sequentially assigned to non-overlapping PDSCH candidates whose last symbols are based on the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook is configured based on the multiple HARQ-ACK occasions.

9. 9. The method of claim 8, wherein when time domain bundling is applied to the semi-static HARQ-ACK codebook, the multiple HARQ-ACK opportunities are allocated based on a PDSCH candidate of the last slot available for PDSCH allocation for each bundling group based on each entry of the TDRA table.

10. 7. The method of claim 6, wherein the wireless communication system comprises a 3rd generation partnership project (3GPP) new radio (NR) based wireless communication system.

11. A base station for use in a wireless communication system, comprising: Communication module and A processor for controlling the communication module, the processor comprising: The PDCCH (physical downlink control channel) having information, the information being Index information indicating an entry in a time-domain resource allocation (TDRA) table for a physical downlink shared channel (PDSCH) allocation; and K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 ｉ } (i=1, 2, . . . ), If the timing information indicates slot n, then for all K1 values ​​in the K1 set, slot n-K1 ｉ determining PDSCH candidates; and receiving a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot; When determining the PDSCH candidate, the K1 set is replaced with a union of K sets #i based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values; The K set #i: {K1 ｉ +d １ , K1 ｉ +d ２ ,...,K1 ｉ +d Ｎ }、 Here, d ｋ (k=1, 2, . . . , N) corresponds to the slot index difference between the last slot for which PDSCH allocation is available and the kth slot for which PDSCH allocation is available based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

12. The base station of claim 11, wherein a subcarrier spacing (SCS) applied to a slot for transmitting the PDCCH is the same as a SCS applied to a slot for transmitting the semi-static HARQ-ACK codebook.

13. The base station of claim 11, wherein for the determined PDSCH candidates for each slot, multiple HARQ-ACK occasions are sequentially assigned to PDSCH candidates whose last symbols do not overlap with the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook is configured based on the multiple HARQ-ACK occasions.

14. The base station of claim 13, wherein when time domain bundling is applied to the semi-static HARQ-ACK codebook, the multiple HARQ-ACK opportunities are allocated based on the PDSCH candidate of the last slot in which PDSCH allocation is possible for each bundling group based on each entry of the TDRA table.

15. 12. The base station of claim 11, wherein the wireless communication system comprises a 3rd generation partnership project (3GPP) new radio (NR) based wireless communication system.

16. 1. A method for use by a base station in a wireless communication system, comprising: transmitting a physical downlink control channel (PDCCH) having information, the information comprising: Index information indicating an entry in a time-domain resource allocation (TDRA) table for a physical downlink shared channel (PDSCH) allocation; and K1 set for PDSCH-to-HARQ (hybrid automatic repeat and request) slot timing {K1 ｉ } (i=1, 2, . . . ), If the timing information indicates slot n, then for all K1 values ​​in the K1 set, slot n-K1 ｉ determining PDSCH candidates; and receiving a semi-static HARQ-ACK codebook in the slot n based on the determined PDSCH candidates for each slot; When determining the PDSCH candidate, the K1 set is replaced with a union of K sets #i based on at least one entry in the TDRA table being associated with a plurality of PDCCH-to-PDSCH slot timing K0 values; The K set #i: {K1 ｉ +d １ , K1 ｉ +d ２ ,...,K1 ｉ +d Ｎ }、 Here, d ｋ (k=1, 2, . . . , N) corresponds to the slot index difference between the last slot available for PDSCH allocation and the kth slot available for PDSCH allocation based on the multiple PDCCH-to-PDSCH timing K0 values ​​across all entries of the TDRA table.

17. The method of claim 16, wherein a subcarrier spacing (SCS) applied to a slot for transmitting the PDCCH is the same as a SCS applied to a slot for transmitting the semi-static HARQ-ACK codebook.

18. The method of claim 16, wherein for the determined PDSCH candidates for each slot, multiple HARQ-ACK occasions are sequentially assigned to non-overlapping PDSCH candidates whose last symbols are based on the earliest PDSCH candidate, and the semi-static HARQ-ACK codebook is configured based on the multiple HARQ-ACK occasions.

19. 19. The method of claim 18, wherein when time domain bundling is applied to the semi-static HARQ-ACK codebook, the multiple HARQ-ACK opportunities are allocated based on a PDSCH candidate of the last slot available for PDSCH allocation for each bundling group based on each entry of the TDRA table.

20. 17. The method of claim 16, wherein the wireless communication system comprises a 3rd generation partnership project (3GPP) new radio (NR) based wireless communication system.

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