Terminal and communication method

Abstract

To appropriately configure a reference PDSCH in multi-carrier scheduling.SOLUTION: A terminal includes a control unit that determines a reference downlink data channel on the basis of the subcarrier spacing and the time of the last scheduled downlink data channel in each cell within multiple cells in multi-cell scheduling, and a transmission unit that transmits a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station on the basis of the transmission timing of the HARQ-ACK determined by the reference downlink data channel.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a terminal and a communication method in a wireless communication system. [Background technology]

[0002] 3GPP (registered trademark) (3rd Generation Partnership Project) is standardizing technologies to achieve even larger system capacity, even faster data transmission speeds, and even lower latency in wireless sections (e.g., Non-Patent Documents 1 and 2).

[0003] Among these technologies, multi-carrier scheduling (which may also be called multi-cell scheduling) is defined as multi-carrier enhancements (MCE) in 3GPP Release 18 to reduce signaling overhead. Multi-carrier scheduling enables scheduling of multiple cells with one downlink control information (DCI) (e.g., Non-Patent Document 3 and Non-Patent Document 4).

[0004] In addition, in 3GPP Release-18, in multi-carrier scheduling, multiple cells that can be scheduled by one downlink control information are restricted to all having the same subcarrier spacing (SCS) and carrier type. In 3GPP Release-19, this restriction has been relaxed to support co-scheduling of cells with different SCSs and carrier types. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] 3GPP TS 38.300 V18.3.0(2024-09) [Non-patent document 2] 3GPP TS 38.401 V18.3.0(2024-09) [Non-patent document 3] 3GPP TS 38.212 V18.2.0(2024-09) [Non-patent document 4] 3GPP TS 38.331 V18.3.0(2024-09) [Non-patent document 5] 3GPP TS 38.214 V18.4.0(2024-09) Summary of the Invention [Problem to be solved by the invention]

[0006] The timing of transmitting HARQ-ACK is determined to be the point when the processing time (Tproc,1) for the reference PDSCH has elapsed since the last scheduled reference PDSCH, where Tproc,1 varies depending on the SCS.

[0007] Therefore, in joint scheduling for cells with different SCSs and carrier types supported in 3GPP Rel-19, the time after the processing time for the last PDSCH in multiple cells does not necessarily become the latest time, and therefore the last PDSCH may not be suitable as a reference PDSCH.

[0008] The present invention has been made in view of the above problems, and has as its object to appropriately set a reference PDSCH in multi-carrier scheduling. [Means for solving the problem]

[0009] According to the disclosed technology, there is provided a terminal having: a control unit that determines a reference downlink data channel based on the subcarrier spacing and the time of the last scheduled downlink data channel in each cell within a plurality of cells in multi-cell scheduling; and a transmission unit that transmits a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station based on the transmission timing of the HARQ-ACK determined by the reference downlink data channel. [Effects of the Invention]

[0010] According to the disclosed technology, it is possible to appropriately set a reference PDSCH in multi-carrier scheduling. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram showing an example (1) of the configuration of a wireless communication system according to the present embodiment. [Figure 2] FIG. 2 is a diagram showing an example (2) of the configuration of a wireless communication system according to the present embodiment. [Figure 3] FIG. 10 is a diagram illustrating the timing of transmitting HARQ-ACK feedback in multi-carrier scheduling. [Figure 4] FIG. 10 is a diagram for explaining the processing time for a reference PDSCH. [Figure 5] FIG. 10 is a diagram for explaining the last scheduled PDSCH in multi-carrier scheduling (Case A). [Figure 6] FIG. 10 is a diagram for explaining the last scheduled PDSCH in multi-carrier scheduling (Case B). [Figure 7] FIG. 10 is a diagram for explaining the last scheduled PDSCH in multi-carrier scheduling (Case C). [Figure 8]FIG. 10 is a diagram for explaining a method for determining a reference PDSCH in this embodiment. [Figure 9] FIG. 2 is a diagram illustrating an example of a functional configuration of a base station according to the present embodiment. [Figure 10] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal according to the present embodiment. [Figure 11] FIG. 2 is a diagram illustrating an example of the hardware configuration of a base station and a terminal according to the present embodiment. [Figure 12] 1 is a diagram illustrating an example of a configuration of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are merely examples, and the embodiments to which the present invention is applicable are not limited to the following embodiments.

[0013] In the following description, unless otherwise specified or unless a different meaning is clear from the context, " / " means "and / or."

[0014] In the operation of the wireless communication system of this embodiment, existing technologies are used as appropriate. However, the existing technologies are, for example, existing LTE (Long Term Evolution), but are not limited to existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and systems subsequent to LTE-Advanced (for example, NR (New Radio)) unless otherwise specified.

[0015] In the present embodiment described below, terms used in existing LTE, such as synchronization signal (SS), primary synchronization signal (PSS), secondary synchronization signal (SSS), physical broadcast channel (PBCH), physical random access channel (PRACH), physical downlink control channel (PDCCH), physical downlink shared channel (PDSCH), physical uplink control channel (PUCCH), and physical uplink shared channel (PUSCH), are used. This is for convenience of description, and similar signals, functions, and the like may be called by other names. The above-mentioned terms in NR may be referred to as SS, PSS, SSS, PBCH, PRACH, and the like without any particular distinction from those in LTE.

[0016] In this embodiment, the duplex method may be a time division duplex (TDD) method, a frequency division duplex (FDD) method, or another method (for example, flexible duplex, etc.).

[0017] In this embodiment, when radio parameters etc. are "configured," it may mean that a predetermined value is pre-configured, or that radio parameters notified from a base station or a terminal are set.

[0018] Fig. 1 is a diagram (1) showing an example of the configuration of a wireless communication system in this embodiment. As shown in Fig. 1, the wireless communication system in this embodiment includes a base station 10 and a terminal 20. Although Fig. 1 shows one base station 10 and one terminal 20, this is an example, and there may be a plurality of each.

[0019] The base station 10 is a communication device that provides one or more cells and performs wireless communication with the terminal 20. The physical resources of a wireless signal are defined in the time domain and the frequency domain. The time domain may be defined by the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols, and the frequency domain may be defined by the number of subcarriers or the number of resource blocks. The base station 10 transmits a synchronization signal (SS) and system information (SI) to the terminal 20. The synchronization signal (SS) is, for example, a PSS and an SSS. The system information is transmitted, for example, via a PBCH or a PDSCH, and is also referred to as broadcast information. The synchronization signal (SS) and system information (SI) may also be referred to as a synchronization signal block (SS / PBCH Block). As shown in FIG. 1 , the base station 10 transmits a control signal or data to the terminal 20 on a downlink (DL) and receives a control signal or data from the terminal 20 on an uplink (UL). Both the base station 10 and the terminal 20 are capable of transmitting and receiving signals by performing beamforming. Furthermore, both the base station 10 and the terminal 20 can apply Multiple Input Multiple Output (MIMO) communication to DL or UL. Furthermore, both the base station 10 and the terminal 20 may communicate via a secondary cell (SCell) and a primary cell (PCell) using carrier aggregation (CA). Furthermore, the terminal 20 may communicate via a PCell of the base station 10 and a primary secondary cell group cell (PSCell) of another base station 10 using dual connectivity (DC).

[0020] The terminal 20 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, or an M2M (Machine-to-Machine) communication module. As shown in Fig. 1, the terminal 20 receives control signals or data from the base station 10 via DL and transmits control signals or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system. The terminal 20 also receives various reference signals transmitted from the base station 10 and measures the propagation path (channel) quality based on the reception results of the reference signals.

[0021] FIG. 2 is a diagram (2) showing an example of the configuration of a wireless communication system according to this embodiment.

[0022] As shown in FIG. 2, the terminal 20 communicates with a base station 10A provided by the NR system and a base station 10B provided by the NR system (hereinafter, when the base stations 10A and 10B are not distinguished from each other, they may be referred to as "base station 10"). Furthermore, the terminal 20 supports NR-NR dual connectivity, i.e., NR-DC, in which the base station 10A is the master node (MN) and the base station 10B is the secondary node (SN). The terminal 20 can simultaneously use multiple component carriers (CCs) provided by the base station 10A, which is the master node, and the base station 10B, which is the secondary node, to perform simultaneous transmission or reception with the base station 10A, which is the master node, and the base station 10B, which is the secondary node.

[0023] 2, the terminal 20 may communicate with a base station 10A provided by an LTE system and a base station 10B provided by an NR system. Furthermore, the terminal 20 may support LTE-NR dual connectivity, i.e., EN-DC, in which the base station 10A is an MN and the base station 10B is an SN. The terminal 20 can simultaneously use multiple CCs provided by the base station 10A, which is the master node, and the base station 10B, which is the secondary node, to perform simultaneous transmission or reception with the base station 10A, which is the master node, and the base station 10B, which is the secondary node.

[0024] 2, the terminal 20 may communicate with a base station 10A provided by the NR system and a base station 10B provided by the LTE system. Furthermore, the terminal 20 may support NR-LTE dual connectivity, i.e., NE (NR-E-UTRA (Evolved Universal Terrestrial Radio Access Network))-DC, in which the base station 10A is an MN and the base station 10B is an SN. The terminal 20 can simultaneously use multiple CCs provided by the base station 10A, which is the master node, and the base station 10B, which is the secondary node, to perform simultaneous transmission or reception with the base station 10A, which is the master node, and the base station 10B, which is the secondary node.

[0025] 2, the terminal 20 may communicate with a base station 10A provided by the NR system and a base station 10B provided by the NR system. Furthermore, the terminal 20 may support NR-NR dual connectivity, i.e., NR-DC, in which the base station 10A is an MN and the base station 10B is an SN. The terminal 20 can simultaneously use multiple CCs provided by the base station 10A, which is the master node, and the base station 10B, which is the secondary node, to perform simultaneous transmission or reception with the base station 10A, which is the master node, and the base station 10B, which is the secondary node.

[0026] Terminal 20 in this embodiment may perform communication using one serving cell, or may perform communication using multiple serving cells (e.g., CA or DC). The processing operations in this embodiment may be executed in the system configuration shown in Fig. 1, the system configuration shown in Fig. 2, or other system configurations.

[0027] In the following description, "multiple" and "multi" may be used interchangeably. For example, multiple PDSCH / PUSCH and multi-PDSCH / PUSCH may be synonymous. Also, "one", "single", and "single" may be used interchangeably. For example, one PDSCH / PUSCH, a single PDSCH / PUSCH, and a single PDSCH / PUSCH may be synonymous.

[0028] In the following description, "HARQ-ACK feedback," "HARQ-ACK information," "HARQ-ACK feedback information," "HARQ-ACK bit," and "feedback information" may be used interchangeably. "Type 1 HARQ-ACK CB," "Type 1 HARQ CB," "Type 1 HARQ-ACK feedback," and "Type 1 CB" may be used interchangeably. "Type 2 HARQ-ACK CB," "Type 2 HARQ CB," "Type 2 HARQ-ACK feedback," and "Type 2 CB" may be used interchangeably.

[0029] In the following description, parameter setting may basically mean parameter setting by Radio Resource Control (RRC). The terms "higher layer parameter," "RRC parameter," and "information element (IE)" may be used interchangeably.

[0030] The agreement on MCE in 3GPP Release 19 is as follows:

[0031] For multi-cell PDSCH / PUSCH scheduling using single DCI, the following support is specified:

[0032] (1) Different subcarrier spacing (SCS) / carrier types between simultaneously scheduled cells using a single DCI.

[0033] (2) One or more PDSCH / PUSCHs per cell scheduled by a single DCI.

[0034] (2-1) The maximum number of PDSCH / PUSCH per scheduled cell is 4 or 8.

[0035] (2-2) Type 1 HARQ-ACK CB is not extended for multi-carrier scheduling in 3GPP Release 19.

[0036] (2-3) The maximum number of sub-CBs for Type 2 HARQ-ACK CB is not increased for multi-carrier scheduling in 3GPP Release 19.

[0037] (2-4) It is not assumed that terminal 20 configures both single-cell multi-PDSCH / PUSCH scheduling and multi-cell multi-PDSCH / PUSCH in the same cell or different cells in the same PUCCH group.

[0038] (3) No new DCI formats will be introduced.

[0039] The multi-carrier scheduling supported by MCE in 3GPP Release 18 is expected to be extended in 3GPP Release 19 in terms of the above-mentioned agreements (1) and (2). For example, as shown in agreement (1), in 3GPP Release 18, multiple cells that can be scheduled with a single DCI (e.g., DCI format 1_3 / 0_3) were restricted to all having the same subcarrier spacing (SCS) / carrier type. However, in 3GPP Release 19, this restriction will be relaxed to enable co-scheduling of cells with different subcarrier spacings (SCS) / carrier types.

[0040] Fig. 3 is a diagram for explaining the transmission timing of HARQ-ACK feedback in multi-carrier scheduling. As shown in Fig. 3, a PUCCH including information on HARQ feedback is transmitted at a time when a specified time (PDSCH-to-HARQ-timing) has elapsed since the last-scheduled PDSCH in all cells (CC#0 to CC#3) in the multi-cell system.

[0041] Fig. 4 is a diagram for explaining the processing time for the reference PDSCH. The description shown in Fig. 4 is the content described in Section 5.3 of Non-Patent Document 5, and the transmission timing of the HARQ-ACK is to transmit it on the PUCCH after the processing time (Tproc,1) calculated using the last scheduled PDSCH (last ending PDSCH) has elapsed, using the reference PDSCH. The processing time is set by PDSCH-to-HARQ-timing. Furthermore, the value of variable N1, which determines the processing time (Tproc,1), varies depending on the subcarrier spacing (SCS) of the reference PDSCH.

[0042] Therefore, in multi-carrier scheduling in 3GPP Rel-19, when different SCS / carrier types exist within a co-scheduled cell scheduled from one DCI format 0_3 / 1_3, the last ending PDSCH does not necessarily have the longest processing time (Tproc,1); the smaller the SCS, the larger the value of the processing time (Tproc,1).

[0043] That is, there are cases where it is not appropriate to use the last scheduled PDSCH (last ending PDSCH) as the reference PDSCH.

[0044] There are three cases (Case A to Case C) for the PDSCH scheduled last in multi-carrier scheduling.

[0045] 5 is a diagram for explaining the last scheduled PDSCH in multi-carrier scheduling (Case A). As shown in FIG. 5, in Case A, if the PDSCH with the smallest SCS is last scheduled (last ending) in a co-scheduled cell, the reference PDSCH can be set to the last scheduled PDSCH with the smallest SCS.

[0046] 6 is a diagram (Case B) for explaining the last scheduled PDSCH in multi-carrier scheduling. As shown in FIG. 6, in Case B, if a PDSCH that does not have the smallest SCS is last scheduled (last ending) in a co-scheduled cell, the reference PDSCH cannot be set to the last scheduled PDSCH (last ending PDSCH) with the smallest SCS. Here, when multiple PDSCHs are last scheduled PDSCHs (last ending) in a co-scheduled cell, the case where the PDSCH with the smallest SCS is not included in the multiple PDSCHs is also included in Case B.

[0047] 6 is a diagram (Case C) for explaining the last scheduled PDSCH in multi-carrier scheduling. As shown in FIG. 6, in Case C, when multiple PDSCHs are last ending PDSCHs in a co-scheduled cell and the multiple PDSCHs include a PDSCH with the smallest SCS, the PDSCH with the smallest SCS among the multiple PDSCHs can be set as the reference PDSCH.

[0048] Hereinafter, a method for appropriately configuring a reference PDSCH in multi-carrier scheduling will be described. Here, PDSCH (downlink data channel) may be replaced with PUSCH (uplink data channel). Furthermore, "DCI 1_3" and "DCI 0_3", and "DCI 1_1" and "DCI 0_1" may be interchangeable. Furthermore, "Cell", "CC", and "entry" may be interchangeable. Furthermore, "network (NW)" and "base station 10" may be interchangeable. Furthermore, "configured (from NW)" may be interchangeable with "configured by RRC", "activated / deactivated / updated by MAC-CE", and "indicated by DCI". Furthermore, a combination of the following methods may be used.

[0049] (Method 1) The base station 10 and the terminal 20 may assume that a reference PDSCH for determining the timing of transmitting the HARQ-ACK (HARQ-ACK timing) is determined by the following method. The terminal 20 may transmit the HARQ-ACK to the base station 10 at a timing calculated based on the determined reference PDSCH.

[0050] For example, the terminal 20 may determine a reference downlink data channel based on the subcarrier spacing in each cell within multiple cells in multi-cell scheduling and the time of the last scheduled downlink data channel, and transmit the HARQ-ACK to the base station 10 based on the transmission timing of the HARQ-ACK determined by the reference downlink data channel.

[0051] (Method 1-1) Fig. 8 is a diagram for explaining a method for determining a reference PDSCH in this embodiment. As shown in Fig. 8, the base station 10 and the terminal 20 may assume that the reference PDSCH is determined taking into consideration the value of the processing time (Tproc,1) of each cell in the co-scheduling cell. For example, the base station 10 and the terminal 20 may determine, as the reference PDSCH, the PDSCH whose time when each PDSCH in each cell ends or the time when each PDSCH in each cell ends plus the processing time (Tproc,1) of each PDSCH is the latest (the last on the time axis).

[0052] (Method 1-2) When certain prerequisites are satisfied, the base station 10 and the terminal 20 may determine the reference PDSCH based on operations based on existing specifications (Rel-18). For example, when the last scheduled (Ending last) PDSCH and the PDSCH with the smallest SCS are the same as in Case A shown in Fig. 5, or when the PDSCH with the smallest SCS (in the co-scheduling cell) is included among the multiple PDSCHs last scheduled in the co-scheduling cell (Ending last PDSCH(s)), as in Case C shown in Fig. 7, the base station 10 and the terminal 20 may omit the processing of method 1-1 and determine the PDSCH with the smallest SCS as the reference PDSCH.

[0053] (Method 1-3) The base station 10 and the terminal 20 may determine the reference PDSCH by performing a prescribed operation based on the existing specifications (Rel-18) when certain preconditions are met. For example, it may be assumed that the processing according to method 1-1 is performed when the last scheduled PDSCH (ending last PDSCH) and the PDSCH with the smallest SCS are different.

[0054] (Method 1-4) The base station 10 and the terminal 20 may assume that they do not calculate the PDSCH processing time (Tproc,1) for all carriers / cells (CCs) when certain conditions are met. For example, when the number of scheduled PDSCHs (number of scheduled PDSCHs) differs by a certain amount or more between co-scheduled cells, the base station 10 and the terminal 20 may narrow down the PDSCHs that are candidates for the reference PDSCH, that is, select a PDSCH candidate, and calculate the processing time (Tproc.1) for the selected PDSCH candidate. For example, the PDSCH candidate that was last scheduled in a cell where the number of PDSCHs is four or more may be selected.

[0055] By using the above-described method, it is possible to appropriately configure the reference PDSCH in multi-carrier scheduling. <Device configuration> An example of the functional configuration of the base station 10 and the terminal 20 that execute the processes and operations described above will be described. The base station 10 and the terminal 20 include functions for implementing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions of the embodiments. ≪Base station≫ Fig. 9 is a diagram showing an example of the functional configuration of a base station in this embodiment. As shown in Fig. 9, base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Fig. 9 is merely an example. The functional divisions and names of the functional units may be any names as long as they can perform the operations according to this embodiment.

[0056] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiver 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of a higher layer from the received signal. The receiver 120 receives capability information related to time-domain HARQ bundling for Type 1 / 2 HARQ CB from the terminal 20. The transmitter 110 also has a function of transmitting PSS, SSS, PBCH, DL / UL control signals, etc. to the terminal 20. The receiver 120 also receives inter-network node messages from other network nodes.

[0057] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20. The content of the setting information is, for example, information related to measurements of low-power signals.

[0058] As described in the embodiments, the control unit 140 controls the settings, instructions, and notifications related to HARQ-ACK feedback / HARQ-ACK bundling. The signal transmission-related functional unit in the control unit 140 may be included in the transmitting unit 110, and the signal reception-related functional unit in the control unit 140 may be included in the receiving unit 120. Terminal Fig. 10 is a diagram showing an example of the functional configuration of a terminal in this embodiment. As shown in Fig. 10, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Fig. 10 is merely an example. As long as the operations according to this embodiment can be performed, the names of the functional divisions and functional units may be any. The transmitting unit 210 and the receiving unit 220 may be collectively referred to as a communication unit.

[0059] The transmitter 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The transmitter 210 transmits capability information related to time-domain HARQ bundling for Type 1 / 2 HARQ CB to the base station 10. The transmitter 210 transmits feedback information such as HARQ-ACK information generated and bundled by the control unit 240. The transmitter 210 transmits PUSCH and other signals based on the radio resources specified by the control unit 240. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals. The receiver 220 has a function of receiving PSS, SSS, PBCH, DL / UL / SL control signals and other signals transmitted from the base station 10. The receiver 220 receives configuration information, instructions, notifications, and other information related to HARQ-ACK feedback / HARQ-ACK bundling from the base station 10. The receiver 220 receives PDSCH and other signals based on the radio resources specified by the control unit 240. The setting unit 230 stores various pieces of setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores various pieces of setting information that are set in advance.

[0060] As described in the embodiments, the control unit 240 controls the settings, instructions, and notifications related to HARQ-ACK feedback / HARQ-ACK bundling. The control unit 240 generates feedback information such as HARQ-ACK information. The control unit 240 bundles feedback information such as HARQ-ACK information. The control unit 240 identifies radio resources based on setting information related to the TDRA table. The signal transmission-related functional unit of the control unit 240 may be included in the transmitting unit 210, and the signal reception-related functional unit of the control unit 240 may be included in the receiving unit 220. <Hardware configuration> The block diagrams (FIGS. 9 and 10) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or may be realized using two or more devices that are physically or logically separated and connected directly or indirectly (for example, by wire, wirelessly, etc.). The functional block may be realized by combining software with the one device or the multiple devices.

[0061] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs a transmission function is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0062] 11 is a diagram showing an example of the hardware configuration of a base station and a terminal in this embodiment. For example, the base station 10, the terminal 20, etc. in this embodiment may function as a computer that performs processing of the wireless communication method of this embodiment. The above-mentioned base station 10 and the terminal 20 may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0063] In the following description, the term "device" can be read as a circuit, a device, a unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the devices shown in Fig. 11, or may be configured to exclude some of the devices.

[0064] Each function in the base station 10 and the terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001, the memory device 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of reading and writing data in the memory device 1002 and the auxiliary memory device 1003.

[0065] The processor 1001 controls the entire computer by running, for example, an operating system (OS). The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 140, control unit 240, etc. may be realized by the processor 1001.

[0066] Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 140 of the base station 10 shown in FIG. 9 may be implemented by a control program stored in the storage device 1002 and executed by the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 10 may be implemented by a control program stored in the storage device 1002 and executed by the processor 1001. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0067] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The storage device 1002 may also be called a register, a cache, a main memory, etc. The storage device 1002 can store executable programs (program codes), software modules, etc. for implementing a communication method according to an embodiment of the present disclosure.

[0068] The secondary storage device 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other suitable medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0069] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of FDD and TDD. For example, a transmitting / receiving antenna, an amplifier unit, a transmitting / receiving unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmitting / receiving unit may be implemented as a transmitting unit and a receiving unit that are physically or logically separated.

[0070] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED (Light-Emitting Diode) lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0071] Furthermore, each device such as the processor 1001 and the storage device 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0072] Furthermore, base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, processor 1001 may be implemented using at least one of these pieces of hardware.

[0073] Fig. 12 is a diagram showing an example of the configuration of a vehicle in this embodiment. As shown in Fig. 12, a vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in the present disclosure may be applied to a communication device mounted on the vehicle 2001, for example, to the communication module 2013.

[0074] The drive unit 2002 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle), and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0075] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (I / O (Input / Output) port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2029 provided in the vehicle 2001. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0076] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a front or rear wheel rotation speed signal obtained by a rotation speed sensor 2022, a front or rear wheel air pressure signal obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0077] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) various types of information, such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 2012 uses information acquired from external devices via the communication module 2013 or the like to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001. The information service unit 2012 may include input devices (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accept input from the outside, and may also include output devices (e.g., a display, a speaker, an LED lamp, a touch panel, etc.) that output information to the outside.

[0078] The driving assistance system unit 2030 is configured with various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS (Global Navigation Satellite System)), map information (e.g., HD (High Definition) maps, autonomous vehicle (AV) maps), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System)), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize driving assistance functions or autonomous driving functions.

[0079] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 29, which are provided in the vehicle 2001.

[0080] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0081] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0082] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle-to-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021 to 2029, etc. provided in the vehicle 2001.

[0083] For example, aspects of the present invention are as follows. <1> a control unit that determines a reference downlink data channel based on a subcarrier interval and a time of the last scheduled downlink data channel in each cell in a plurality of cells in multi-cell scheduling; a transmitter that transmits a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station based on a transmission timing of the HARQ-ACK determined by the reference downlink data channel; A terminal having: <2> the control unit determines, as the reference downlink data channel, a downlink data channel having the latest time obtained by adding a processing time for the downlink data channel determined based on the subcarrier interval to the time of the downlink data channel. <1> A terminal described in. <3> the control unit determines the last scheduled downlink data channel as the reference downlink data channel when a subcarrier spacing for the last scheduled downlink data channel in the plurality of cells is smallest among the plurality of cells; <1> A terminal described in. <4> When the subcarrier interval for the most recently scheduled downlink data channel in the plurality of cells is not the smallest among the plurality of cells, the control unit determines the downlink data channel having the latest time obtained by adding the processing time for the downlink data channel determined based on the subcarrier interval to the time of the downlink data channel as the reference downlink data channel. <1> A terminal described in. <5> the control unit calculates the processing time only for the last scheduled downlink data channel in a cell in which the number of scheduled downlink data channels is equal to or greater than a predetermined number, and sets the last scheduled downlink data channel as a candidate for the reference downlink data channel. <1> A terminal described in. <6> determining a reference downlink data channel based on a subcarrier spacing and a time of the last scheduled downlink data channel in each cell in the multiple cells in the multi-cell scheduling; transmitting a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station based on a transmission timing of the HARQ-ACK determined by the reference downlink data channel; A communication method performed by a terminal having the

[0084] Any of the above configurations makes it possible to appropriately configure the reference PDSCH in multi-carrier scheduling. <Supplementary information on the embodiment> Although the present embodiment has been described above, the disclosed invention is not limited to such an embodiment, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be used in combination as needed, and matters described in one item may apply to matters described in another item (unless inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of the processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams. However, such devices may be implemented using hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to this embodiment and the software operated by the processor of the terminal 20 according to this embodiment may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

[0085] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., DCI, UCI (Uplink Control Information)), higher layer signaling (e.g., RRC signaling, MAC signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or a combination thereof. Information notified by higher layer signaling may be referred to as configuration information. Information notified by physical layer signaling may be referred to as control information. Furthermore, RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0086] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR, W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-Wideband), Bluetooth (registered trademark), or other suitable systems, and next-generation systems extended based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G) may also be applied.

[0087] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

[0088] In this specification, a specific operation that is described as being performed by the base station 10 may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having the base station 10, it is clear that various operations performed for communication with the terminal 20 may be performed by at least one of the base station 10 and another network node other than the base station 10 (such as, but not limited to, an MME (Mobility Management Entity) or an S-GW (Serving Gateway)). Although the above example illustrates a case where there is one other network node other than the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

[0089] The information, signals, etc. described in the present disclosure may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0090] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0091] In the present disclosure, the determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0092] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0093] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0094] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0095] Note that terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). A signal may also be a message. A CC may also be called a carrier frequency, a cell, a frequency carrier, etc.

[0096] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0097] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or other corresponding information. For example, a radio resource may be indicated by an index.

[0098] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0099] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station device," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0100] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head)). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within that coverage.

[0101] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0102] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0103] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0104] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be a mobile object that moves autonomously based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0105] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between a plurality of terminals 20 (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)). In such a case, the terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0106] Similarly, the user terminal in the present disclosure may be read as a base station. In such a case, the base station may be configured to have the functions of the user terminal described above.

[0107] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0108] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables, and printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0109] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0110] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0111] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0112] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0113] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0114] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0115] Numerology may be communication parameters applied to at least one of transmission and reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, and specific windowing operations performed by the transceiver in the time domain.

[0116] A slot may be composed of one or more symbols (such as OFDM symbols or SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols) in the time domain. A slot may be a time unit based on numerology.

[0117] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0118] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0119] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 millisecond (ms)) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0120] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate wireless resources (such as frequency bandwidth and transmission power that can be used by each terminal 20) to each terminal 20 in TTI units. Note that the definition of TTI is not limited to this.

[0121] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0122] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0123] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Releases 8 to 12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial TTI (partial or fractional TTI), shortened subframe, short subframe, minislot, subslot, slot, etc.

[0124] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0125] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0126] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0127] Note that one or more RBs may also be called a physical resource block (PRB), a subcarrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0128] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0129] A BandWidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common RBs for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within the BWP.

[0130] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0131] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0132] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0133] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0134] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0135] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0136] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]

[0137] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 terminals 210 Transmitter 220 Receiving unit 230 Setting Section 240 Control Unit 1001 processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication equipment 1005 Input Device 1006 Output Device 2001 Vehicle 2002 Drive unit 2003 Steering Section 2004 accelerator pedal 2005 brake pedal 2006 Shift Lever 2007 front wheel 2008 rear wheel 2009 Axle 2010 Electronic Control Unit 2012 Information Services Department 2013 Communication Module 2021 Current Sensor 2022 RPM Sensor 2023 Air Pressure Sensor 2024 Vehicle speed sensor 2025 Acceleration Sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving Assistance Systems Department 2031 microprocessor 2032 memory (ROM, RAM) 2033 Communication port (I / O port)

Claims

1. a control unit that determines a reference downlink data channel based on a subcarrier interval and a time of the last scheduled downlink data channel in each cell in a plurality of cells in multi-cell scheduling; a transmitter that transmits a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station based on a transmission timing of the HARQ-ACK determined by the reference downlink data channel; A terminal having:

2. the control unit determines, as the reference downlink data channel, a downlink data channel having the latest time obtained by adding a processing time for the downlink data channel determined based on the subcarrier interval to the time of the downlink data channel. The terminal according to claim 1 .

3. the control unit determines the last scheduled downlink data channel as the reference downlink data channel when a subcarrier spacing for the last scheduled downlink data channel in the plurality of cells is smallest among the plurality of cells; The terminal according to claim 1 .

4. When the subcarrier interval for the most recently scheduled downlink data channel in the plurality of cells is not the smallest among the plurality of cells, the control unit determines the downlink data channel having the latest time obtained by adding the processing time for the downlink data channel determined based on the subcarrier interval to the time of the downlink data channel as the reference downlink data channel. The terminal according to claim 1 .

5. the control unit calculates the processing time only for the last scheduled downlink data channel in a cell in which the number of scheduled downlink data channels is equal to or greater than a predetermined number, and sets the last scheduled downlink data channel as a candidate for the reference downlink data channel. The terminal according to claim 1 .

6. determining a reference downlink data channel based on a subcarrier spacing and a time of the last scheduled downlink data channel in each cell in the multiple cells in the multi-cell scheduling; transmitting a Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) to a base station based on a transmission timing of the HARQ-ACK determined by the reference downlink data channel; A communication method performed by a terminal having the

Images