Terminal, base station, communication system, and communication method

Abstract

This terminal comprises: a reception unit which receives, from a base station, control information and data; a control unit which determines, on the basis of the control information, a carrier that transmits an uplink control channel; and a transmission unit which transmits, to a base station, information pertaining to a control for the retransmission of the data in the determined carrier through the uplink control channel, wherein the control unit determines a timing for transmitting the information pertaining to the control for the retransmission of the data on the basis of an assumption of the carrier that transmits the uplink control channel.

Description

Terminal and communication method

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

[0002] The 3rd Generation Partnership Project (3GPP) is currently studying a wireless communication method called 5G or NR (New Radio) (hereinafter, this wireless communication method will be referred to as "NR") in order to achieve a larger system capacity, a higher data transmission speed, and a lower latency in wireless sections. In 5G, various wireless technologies and network architectures are being studied to meet the requirements of achieving a throughput of 10 Gbps or more while reducing latency in wireless sections to 1 ms or less (for example, Non-Patent Document 1).

[0003] Furthermore, in the 3GPP standardization, PUCCH (Physical Uplink Control Channel) carrier switching is being considered as an extension of URLLC (Ultra-Reliable and Low Latency Communications) technology. For example, PUCCH carrier switching is being considered as a method for reducing the latency of HARQ-ACK (Hybrid Automatic Repeat Request Acknowledgement) feedback in a TDD (Time Division Duplex) system (e.g., Non-Patent Document 2).

[0004] 3GPP TS 38.300 V16.4.0 (2020-12) 3GPP TSG RAN Meeting #88e, RP-201310, Electronic meeting, June 29-July 3, 2020

[0005] When the cell transmitting the PUCCH is expanded to a secondary cell other than the primary cell, the primary secondary cell group cell, or the PUCCH secondary cell, when performing PUCCH carrier switching, the timing of transmitting the HARQ-ACK was unclear depending on the subcarrier spacing applied to the carrier.

[0006] The present invention has been made in view of the above points, and has as its object to determine the timing for transmitting a response related to retransmission control on an uplink control channel in a wireless communication system.

[0007] According to the disclosed technology, a terminal is provided that has a receiving unit that receives control information and data from a base station, a control unit that determines a carrier for transmitting an uplink control channel based on the control information, and a transmitting unit that transmits information related to retransmission control of the data on the determined carrier to the base station via the uplink control channel, and the control unit determines the timing for transmitting the information related to retransmission control of the data by assuming the carrier for transmitting the uplink control channel.

[0008] According to the disclosed technique, it is possible to determine the timing for transmitting a response related to retransmission control on an uplink control channel in a wireless communication system.

[0009] FIG. 1 is a diagram illustrating an example (1) of a wireless communication system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example (2) of a wireless communication system according to an embodiment of the present invention. FIG. 3 is a flowchart illustrating an example of PUCCH transmission according to an embodiment of the present invention. FIG. 4 is a diagram illustrating an example (1) of PUCCH transmission according to an embodiment of the present invention. FIG. 5 is a diagram illustrating an example (2) of PUCCH transmission according to an embodiment of the present invention. FIG. 6 is a diagram illustrating an example (3) of PUCCH transmission according to an embodiment of the present invention. FIG. 7 is a diagram illustrating an example (4) of PUCCH transmission according to an embodiment of the present invention. FIG. 8 is a diagram illustrating an example (6) of PUCCH transmission according to an embodiment of the present invention. FIG. 9 is a diagram illustrating an example (7) of PUCCH transmission according to an embodiment of the present invention. FIG. 10 is a diagram illustrating an example of MAC-CE according to an embodiment of the present invention. FIG. 11 is a diagram illustrating an example (8) of PUCCH transmission according to an embodiment of the present invention. FIG. 12 is a diagram illustrating an example (9) of PUCCH transmission according to an embodiment of the present invention. FIG. 13 is a diagram illustrating an example (1) of PUCCH carrier switching according to an embodiment of the present invention. FIG. 14 is a diagram illustrating an example (2) of PUCCH carrier switching according to an embodiment of the present invention. FIG. 15 is a diagram illustrating an example (3) of PUCCH carrier switching according to an embodiment of the present invention. FIG. 16 is a diagram illustrating an example of PUCCH carrier switching disablement according to an embodiment of the present invention. FIG. 1 is a diagram showing an example (1) of PUCCH transmission power control in an embodiment of the present invention. FIG. 2 is a diagram showing an example (2) of PUCCH transmission power control in an embodiment of the present invention. FIG. 3 is a diagram showing an example (3) of PUCCH transmission power control in an embodiment of the present invention. FIG. 4 is a diagram showing an example (4) of PUCCH transmission power control in an embodiment of the present invention. FIG. 5 is a diagram showing an example (5) of PUCCH transmission power control in an embodiment of the present invention. FIG. 6 is a diagram showing an example of spatial relationship in an embodiment of the present invention. FIG. 7 is a diagram showing an example (6) of PUCCH transmission power control in an embodiment of the present invention. FIG. 8 is a diagram showing an example (1) of UCI multiplexing in an embodiment of the present invention. FIG. 9 is a diagram showing an example (2) of UCI multiplexing in an embodiment of the present invention. FIG. 10 is a diagram showing an example (3) of UCI multiplexing in an embodiment of the present invention. FIG. 11 is a diagram showing an example (4) of UCI multiplexing in an embodiment of the present invention.FIG. 1 is a diagram showing an example (5) of UCI multiplexing in an embodiment of the present invention. FIG. 2 is a diagram showing an example (1) of HARQ-ACK offset in an embodiment of the present invention. FIG. 3 is a diagram showing an example (2) of HARQ-ACK offset in an embodiment of the present invention. FIG. 4 is a diagram showing an example (3) of HARQ-ACK offset in an embodiment of the present invention. FIG. 5 is a diagram showing an example (4) of HARQ-ACK offset in an embodiment of the present invention. FIG. 6 is a diagram showing an example (5) of HARQ-ACK offset in an embodiment of the present invention. FIG. 7 is a diagram showing an example (6) of HARQ-ACK offset in an embodiment of the present invention. FIG. 8 is a diagram showing an example of the functional configuration of a base station 10 in an embodiment of the present invention. FIG. 9 is a diagram showing an example of the functional configuration of a terminal 20 in an embodiment of the present invention. FIG. 10 is a diagram showing an example of the hardware configuration of a base station 10 or a terminal 20 in an embodiment of the present invention.

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0011] In operation of the wireless communication system according to the embodiment of the present invention, an existing technology may be used as appropriate. The existing technology may be, for example, an existing NR or LTE, but is not limited to, an existing NR or LTE.

[0012] Fig. 1 is a diagram for explaining an example (1) of a wireless communication system according to an embodiment of the present invention. As shown in Fig. 1, the wireless communication system according to the embodiment of the present invention 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.

[0013] 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, and the time domain may be defined by the number of OFDM symbols, and the frequency domain may be defined by the number of subcarriers or the number of resource blocks. Furthermore, a TTI (Transmission Time Interval) in the time domain may be a slot, or a TTI may be a subframe.

[0014] The base station 10 is capable of performing carrier aggregation (CA), which aggregates multiple cells (multiple CCs (component carriers)) to communicate with the terminal 20. In carrier aggregation, one PCell (Primary Cell) and one or more SCells (Secondary Cells) are used.

[0015] The base station 10 transmits synchronization signals, system information, and the like to the terminal 20. The synchronization signals are, for example, NR-PSS and NR-SSS. The system information is transmitted, for example, via NR-PBCH or PDSCH, and is also referred to as broadcast information. As shown in FIG. 1, the base station 10 transmits control signals or data to the terminal 20 via DL (Downlink) and receives control signals or data from the terminal 20 via UL (Uplink). Note that, here, signals transmitted via control channels such as PUCCH (Physical Uplink Shared Channel) and PDCCH (Physical Downlink Control Channel) are referred to as control signals, and signals transmitted via shared channels such as PUSCH (Physical Uplink Shared Channel) and PDSCH (Physical Downlink Shared Channel) are referred to as data, but these nomenclatures are merely examples.

[0016] 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 may be referred to as a UE, and the base station 10 may be referred to as a gNB.

[0017] FIG. 2 is a diagram illustrating an example (2) of a wireless communication system according to an embodiment of the present invention. FIG. 2 shows an example of the configuration of a wireless communication system in which dual connectivity (DC) is implemented. As shown in FIG. 2, a base station 10A serving as a master node (MN) and a base station 10B serving as a secondary node (SN) are provided. The base station 10A and the base station 10B are each connected to a core network 30. A terminal 20 can communicate with both the base station 10A and the base station 10B.

[0018] A cell group provided by the base station 10A, which is an MN, is called a master cell group (MCG), and a cell group provided by the base station 10B, which is an SN, is called a secondary cell group (SCG). In dual connectivity, the MCG is composed of one PCell and zero or more SCells, and the SCG is composed of one PSCell (Primary SCG Cell) and zero or more SCells. The PCell or PSCell may be referred to as a special cell (SpCell).

[0019] Note that dual connectivity may be a communication method using two communication standards, and any combination of communication standards may be used. For example, the combination may be NR and 6G, or LTE and 6G. Furthermore, dual connectivity may be a communication method using three or more communication standards, and may be called by a name other than dual connectivity.

[0020] The processing operations in this embodiment may be executed in the system configuration shown in FIG. 1, in the system configuration shown in FIG. 2, or in a system configuration other than these.

[0021] 3GPP standardization is considering supporting enhanced Internet of Things (IoT) and ultra-reliable and low latency communication (URLLC) in NR. Furthermore, to accommodate URLLC requirements, enhancements to HARQ-ACK feedback are being considered. For example, PUCCH carrier switching is being considered to improve the latency of HARQ-ACK feedback.

[0022] Here, the PUCCH resource is set to the PCell, the PSCell, or the PUCCH-SCell. The terminal cannot transmit the PUCCH in any cell other than the PCell, the PSCell, or the PUCCH-SCell. Which cell the PUCCH is to be transmitted from is specified in advance, and it is difficult to flexibly change the cell.

[0023] For example, assume that the following settings are made: PUCCH group 1: CC0 = PCell, CC1 = SCell PUCCH group 2: CC2 = PUCCH-SCell, CC3 = SCell

[0024] At this time, in the case of PUCCH group 1, it was possible to transmit the PUCCH only on CC 0, and it was not possible to transmit the PUCCH on CC 1. In the case of PUCCH group 2, it was possible to transmit the PUCCH only on CC 2, and it was not possible to transmit the PUCCH on CC 3. Furthermore, since the PUCCH-SCell cannot be configured in intraband CA, it was difficult to flexibly change which CC in the intraband to transmit the PUCCH on.

[0025] Therefore, the CC for transmitting the PUCCH may be flexibly selected, and it may be specified which CC the PUCCH is to be transmitted on. For example, PUCCH carrier switching based on dynamic notification by DCI (Downlink Control Information) that schedules the PUCCH may be supported. Also, for example, PUCCH carrier switching based on semi-static settings may be supported. PUCCH carrier switching may mean switching the carrier, CC, or cell for transmitting the PUCCH.

[0026] For example, the semi-static configuration may be based on a PUCCH cell timing pattern configured by RRC (Radio Resource Control), or PUCCH carrier switching between cells with different numerologies or subcarrier spacings may be supported. The PUCCH cell may be a cell capable of transmitting the PUCCH.

[0027] In addition, the maximum number of PUCCH cells may be specified. In addition, dynamic configuration and semi-static configuration may be integrated and applied to PUCCH carrier switching. In addition, PUCCH carrier switching and semi-persistent (SPS) HARQ-ACK postponement may be integrated and applied.

[0028] 3 is a flowchart illustrating an example of PUCCH transmission according to an embodiment of the present invention. In step S1, the terminal 20 receives DCI and PDSCH from the base station 10. In the following step S2, the terminal 20 determines a PUCCH for transmitting a HARQ-ACK corresponding to the received PDSCH. The terminal 20 may determine a cell or carrier for transmitting the PUCCH, a resource for transmitting the PUCCH, and transmission power for transmitting the PUCCH based on control information received from the base station 10. This control information may be, for example, RRC, MAC-CE, and / or DCI. Hereinafter, RRC, MAC-CE, and DCI may be interchangeable. In the following step S3, the terminal 20 transmits the determined PUCCH to the base station 10.

[0029] For example, the base station 10 may indicate the CC to which the PUCCH is to be transmitted using RRC, a Medium Access Control - Control Element (MAC-CE), or DCI. The terminal 20 may transmit the PUCCH on the indicated CC.

[0030] For example, PUCCH #1 transmitted on the PCell or PSCell and PUCCH #2 transmitted on the PUCCH-SCell may be switched by RRC, MAC-CE, or DCI.

[0031] 4 is a diagram showing an example (1) of PUCCH transmission in an embodiment of the present invention. As shown in FIG. 4, switching of the CC transmitting the PUCCH is not limited to the PCell, PSCell, or PUCCH-SCell, and may be instructed by RRC, MAC-CE, and / or DCI. For example, the CC transmitting the PUCCH may be indicated from all configured CCs by RRC, MAC-CE, and / or DCI. Furthermore, for example, one or more predetermined CC lists including some CCs from all configured CCs may be selected or configured in advance, and the CC transmitting the PUCCH may be indicated from among the CCs included in the selected or configured CC list by RRC, MAC-CE, and / or DCI.

[0032] One or more predetermined CC lists including some CCs among all configured CCs may be selected or configured based on a predetermined rule. For example, the predetermined rule may be a list of a predetermined number of CCs starting from the smallest CCID. The predetermined number may be specified by a specification, may be set by a higher layer, or may be notified from the terminal 20 to the base station 10 by a UE capability report.

[0033] Furthermore, for example, one or more predetermined CC lists including some CCs among all configured CCs may be configured by a higher layer. The maximum number of CCs that can be configured per CC list may be notified from the terminal 20 to the base station 10 by a UE capability report.

[0034] Regarding PUCCH carrier switching, both 1) and 2) shown below may be considered.

[0035] 1) When the carrier for transmitting the PUCCH is dynamically indicated. 2) When the carrier for transmitting the PUCCH is semi-statically indicated. For example, when PUCCH carrier switching is performed only when the PUCCH cannot be transmitted in the slot for transmitting the PUCCH indicated by the HARQ feedback timing indicator.

[0036] By transmitting the PUCCH as described above, the degree of congestion of the resources used by the UE varies for each CC, which enables resource distribution. Also, since the TDD setting may differ for each CC, the PUCCH can be transmitted at more flexible timing.

[0037] 5 is a diagram showing an example (2) of PUCCH transmission according to an embodiment of the present invention. The CC of the PUCCH that collectively transmits UCI may be indicated or selected by the MAC-CE and / or DCI from predetermined CC candidates, for example, the first CC list shown in FIG. 5. By setting or defining the first CC list, it is possible to limit the CC candidates that can be indicated by the MAC-CE and / or DCI, thereby reducing signaling overhead and UE complexity.

[0038] 5, a second CC list indicating which CCs' UCI (e.g., HARQ, CSI, etc.) are to be collectively transmitted on the PUCCH may or may not be transmitted from the base station 10 to the terminal 20. If the second list is not transmitted, the terminal 20 may collectively transmit the UCI of all CCs on the PUCCH. These all CCs may be all CCs including the SpCell and SCell, or may be all CCs in the PUCCH cell group.

[0039] 6 is a diagram showing an example (3) of PUCCH transmission according to an embodiment of the present invention. As shown in FIG. 6, the TDD setting may differ for each CC. When a slot specified as HARQ timing is DL, if another CC has UL in that slot, transmitting HARQ-ACK in that other CC makes it possible to reduce HARQ delay compared to conventional methods and improve URLLC performance.

[0040] For example, as shown in Fig. 6, in an SpCell transmitting a PUCCH, if a slot indicated by a HARQ feedback timing indicator (PDSCH to HARQ feedback timing indicator) included in a DCI is unavailable, the CC transmitting the PUCCH may be switched to SCell #1. The condition for this unavailability may be, for example, that the slot is a DL slot, that the UL symbol of the PUCCH is unavailable in a special subframe, or that the UL slot is already assigned to another channel.

[0041] In an embodiment of the present invention, the CC for transmitting the PUCCH is preset by RRC, or the terminal 20 searches for available CCs, so that the CC for transmitting the PUCCH can be switched even when there is no instruction for PUCCH carrier switching by MAC-CE or DCI. Furthermore, the PUCCH may be transmitted in the same slot as the slot indicated by the HARQ feedback timing indicator, or in a slot that at least partially overlaps with the slot indicated by the HARQ feedback timing indicator in the case of a different SCS. When multiple CCs are available, a priority may be specified or set in advance for the CCs. For example, the CC with the smaller CC index may be given priority for transmitting the PUCCH. Candidates for the CC for transmitting the switched PUCCH may be set in advance by a higher layer. This makes it possible to prevent the PUCCH from being transmitted on a CC that is not desired for transmission by the terminal 20.

[0042] FIG. 7 is a diagram showing an example (4) of PUCCH transmission according to an embodiment of the present invention. FIG. 8 is a diagram showing an example (5) of PUCCH transmission according to an embodiment of the present invention. When a slot indicated by the HARQ feedback timing indicator is unavailable in a CC transmitting a PUCCH, the terminal 20 may switch the CC transmitting a PUCCH. Furthermore, as shown in FIG. 7 or 8, when there is no other available CC in the same slot or in a slot that at least partially overlaps, the terminal 20 may change the slot transmitting a HARQ-ACK. FIG. 7 shows an example of changing to an earlier available slot in the time domain, and FIG. 8 shows an example of changing to a later available slot in the time domain. Alternatively, the terminal 20 may not consider the case where there is no other available CC.

[0043] Furthermore, when the base station 10 instructs the terminal 20 on which CC to transmit the PUCCH by RRC, MAC-CE, and / or DCI, the base station 10 and the terminal 20 may first determine the CC to transmit the PUCCH, and then determine the slot to transmit the PUCCH. Furthermore, when the base station 10 instructs the terminal 20 on which CC to transmit the PUCCH by RRC, MAC-CE, and / or DCI, the base station 10 and the terminal 20 may first determine the slot to transmit the PUCCH, and then determine the CC to transmit the PUCCH.

[0044] 9 is a diagram showing an example (6) of PUCCH transmission according to an embodiment of the present invention. As shown in FIG. 9, terminal 20 may transmit HARQ-ACK in a slot and CC in which PUCCH can be transmitted earliest after a predetermined time has elapsed after receiving PDSCH. Note that HARQ-ACK may refer to HARQ feedback and may include an ACK, i.e., a positive response, or a NACK, i.e., a negative response. When an operation is configured by a higher layer, the UE may ignore the presence of some or all of the HARQ feedback timing indicator fields in DCI format 1_0, DCI format 1_1, and DCI format 1_2. Regarding the HARQ-ACK of a PDSCH scheduled with a DCI in which a HARQ feedback timing indicator field is not present, the HARQ-ACK may be transmitted in a slot and CC in which PUCCH can be transmitted earliest after a predetermined time has elapsed after receiving PDSCH. In the method shown in FIG. 9, the delay of HARQ feedback is minimized and signaling such as an HARQ feedback timing indicator is not required, thereby reducing DCI overhead.

[0045] In the example shown in Fig. 9, after receiving the PDSCH, the terminal 20 transmits the PUCCH in SCell #1, which is available for transmission in the nearest slot after a predetermined time has elapsed. Note that, if multiple CCs are available, the priority order among the CCs may be specified or set in advance. For example, a CC with a smaller CC index may be given priority for use in PUCCH transmission. Furthermore, candidates for the CC to which the PUCCH is switched may be set in advance by a higher layer. This makes it possible to prevent the PUCCH from being transmitted in a CC that is not desired to be transmitted by the terminal 20.

[0046] For example, the base station 10 may use DCI to indicate or select a CC for transmitting the PUCCH to the terminal 20. As shown in 1)-3) below, the base station 10 may use a predetermined field in the DCI to indicate a CC for transmitting the PUCCH.

[0047] 1) A new CC indication field may be defined to indicate the CC on which the PUCCH is transmitted. For example, the new CC indication field may be defined in some or all of DCI format 1_0, DCI format 1_1, and DCI format 1_2, which are DCIs for scheduling DL. Table 1 shows an example of the new CC indication field.

[0048]

[0049] As shown in Table 1, the CC for transmitting the PUCCH is specified by the DCI code point. Table 1 shows an example in which the CC indication field is 2 bits. The CC index associated with each DCI code point may be notified by the RRC or MAC-CE.

[0050] 2) The CC for transmitting the PUCCH may be indicated by an existing DCI field. For example, it may be indicated by a PUCCH resource indicator (PRI) field. Table 2 shows an example of indicating the CC for transmitting the PUCCH by the PRI field.

[0051]

[0052] A CC for transmitting the PUCCH may be associated with each PUCCH resource as shown in Table 2. A destination CC associated with each PUCCH resource may be configured by a higher layer.

[0053] 3) An existing DCI field may be used to indicate the CC on which the PUCCH is to be transmitted. For example, the carrier indicator field (CIF) may be used to indicate the CC on which the PUCCH is to be transmitted. For example, the CIF may be present when PUCCH carrier switching is configured regardless of whether the PDSCH is cross-carrier scheduled. The base station 10 may use the CIF to indicate to the terminal 20 the CC on which the PUCCH is to be transmitted.

[0054] When cross-carrier scheduling is configured, a common CIF may be used to indicate the CC on which the PDSCH is scheduled and the CC on which the PUCCH is transmitted. Alternatively, the CIF may be used to indicate the CC on which the PDSCH is scheduled, and the CC on which the PUCCH is transmitted may be indicated by the method 1) or 2) above. Alternatively, the CIF may be extended, and a first CIF may be used to indicate the CC on which the PDSCH is scheduled, and a second CIF may be used to indicate the CC on which the PUCCH is transmitted.

[0055] 10 is a diagram showing an example (7) of PUCCH transmission according to an embodiment of the present invention. When HARQ-ACKs corresponding to multiple PDSCHs triggered or scheduled by multiple DCIs are transmitted on the PUCCH, the CC to be used to transmit the PUSCH indicated by the DCI may be configured or predefined. For example, as shown in FIG. 10, the CC to transmit the PUCCH (CC0 in FIG. 10) may be determined based on the last DCI in the time and frequency directions.

[0056] Fig. 11 is a diagram showing an example of a MAC-CE in an embodiment of the present invention. The base station 10 may use a MAC-CE to indicate to the terminal 20 the CC on which to transmit the PUCCH. As shown in Fig. 11, a MAC-CE may be defined that indicates the CC on which to transmit the PUCCH. The terminal 20 may transmit the PUCCH on the CC indicated by the MAC-CE. One MAC-CE per cell group may indicate the cell on which to transmit the PUCCH, or one MAC-CE per UE may indicate the cell on which to transmit the PUCCH.

[0057] In the example shown in Fig. 10, the MAC-CE may include a cell group index, and the bit size indicating the cell group index may be determined according to the number of cell groups. Furthermore, when a cell that transmits a PUCCH is not designated in units of a cell group, the cell group index may not be included in the MAC-CE. For example, in the example shown in Fig. 10, one cell that transmits a PUCCH from a maximum of eight cells is designated. The terminal 20 n The PUCCH may be transmitted in a cell with .times. ...

[0058] 12 is a diagram showing an example (8) of PUCCH transmission according to an embodiment of the present invention. When performing PUCCH carrier switching, terminal 20 may use the PUCCH resource of the CC that transmits the PUCCH indicated by the MAC-CE and / or DCI, as shown in FIG. 12. For example, terminal 20 may use the PUCCH resource of the scheduled cell that is indicated by the PRI or information indicating the CC that transmits the PUCCH.

[0059] 13 is a diagram showing an example (9) of PUCCH transmission according to an embodiment of the present invention. When performing PUCCH carrier switching, as shown in FIG. 13, terminal 20 may use a PUCCH resource set to a CC on which DCI indicating information indicating a CC on which PRI or PUCCH is transmitted has been received. For example, terminal 20 may use a PUCCH resource of a scheduling cell indicating information indicating a CC on which PRI or PUCCH is transmitted. Furthermore, when transmitting PUCCHs scheduled from multiple CCs as shown in FIG. 13, terminal 20 may use a PUCCH resource set to a CC on which the last DCI (last DCI) in the time and frequency directions has been received.

[0060] Furthermore, when performing PUCCH carrier switching, terminal 20 may use PUCCH resources allocated to the CC on which the PDSCH scheduled by the last DCI is received.

[0061] Note that PUCCH-config may be set for each BWP (Bandwidth Part). The above-mentioned "CC" may be replaced with "BWP within CC." Note that the embodiment of the present invention may operate when PUCCH carrier switching is configured. Furthermore, "PUCCH carrier switching" may be interpreted as "indicating the CC for transmitting PUCCH by RRC, MAC-CE, and / or DCI." Note that slot and subslot may be interpreted interchangeably. Note that SUL (Supplementary Uplink) may or may not be included in the CCs targeted for PUCCH carrier switching. Whether or not SUL is included in the CCs targeted for PUCCH carrier switching may be reported from the terminal 20 to the base station 10 by a UE capability report.

[0062] The embodiment of the present invention may be limited to application to terminals 20 that have reported the UE capabilities shown in 1) and / or 2) below.

[0063] 1) UE capability indicating whether PUCCH carrier switching is supported. For example, this may be a UE capability indicating whether the CC on which the PUCCH is transmitted is indicated by RRC, MAC-CE, and / or DCI. Alternatively, this may be a UE capability indicating whether the CC on which the PUCCH is transmitted is indicated by MAC-CE. Alternatively, this may be a UE capability indicating whether the CC on which the PUCCH is transmitted is indicated by DCI.

[0064] 2) The number of CCs to be switched to in PUCCH carrier switching. This may be the maximum number of CCs that can be set per CC list to be switched to in PUCCH carrier switching.

[0065] Furthermore, as the UE capability, the CC to which PUCCH carrier switching is switched may be set as one or more of the following NR carrier types. For example, the terminal 20 may report carrier types that can transmit PUCCH, and the PUCCH carrier may be switched only to those carrier types.

[0066] The one or more NR carrier types may be {FR1 licensed TDD (fr1-NonSharedTDD-r16), FR1 unlicensed TDD (fr1-SharedTDD-r16), FR1 licensed FDD (fr1-NonSharedFDD-r16), FR2(fr2-r16)}.

[0067] Furthermore, the one or more NR carrier types may be {FR1-NonSharedTDD, FR1-SharedTDD, FR1-NonSharedFDD, FR2}.

[0068] The activation timing of the indication of the CC transmitting the PUCCH may be specified. For example, the time from when the CC transmitting the PUCCH is indicated by RRC, MAC-CE, and / or DCI until the PUCCH carrier switching is actually applied may be specified.

[0069] The base station 10 and the terminal 20 need to have a common understanding of the CC that transmits the PUCCH. By specifying the application timing of the instruction of the CC that transmits the PUCCH, for example, if the terminal 20 fails to receive the instruction, the base station 10 can recognize that the instruction is not valid.

[0070] Note that PUCCH carrier switching may be in a valid or invalid state. An instruction for a CC that transmits a PUCCH may be called an activation command, and an activation command that validates the instruction may be specified separately from the instruction. Also, a deactivation command that invalidates the instruction may be specified.

[0071] 14 is a diagram showing an example (1) of PUCCH carrier switching in an embodiment of the present invention. As shown in FIG. 14, the assumed CC for transmitting the PUCCH may be switched after a predetermined time has elapsed since an ACK is transmitted in response to a MAC-CE indicating the CC for transmitting the PUCCH. This predetermined time may be, for example, 3 ms later, or until the start of the next slot after 3 ms has elapsed. Note that indicating by MAC-CE may mean indicating the CC for transmitting the PUCCH only by MAC-CE, or may mean indicating a CC list including multiple CCs by MAC-CE and indicating one CC by DCI.

[0072] 15 is a diagram illustrating an example (2) of PUCCH carrier switching according to an embodiment of the present invention. As shown in FIG. 15, the assumed CC for transmitting the PUCCH may be switched before transmitting the PUCCH / PUSCH for transmitting an ACK / NACK in response to DCI indicating the CC for transmitting the PUCCH.

[0073] 16 is a diagram showing an example (3) of PUCCH carrier switching according to an embodiment of the present invention. As shown in FIG. 16, the assumed CC for transmitting the PUCCH may be switched after a predetermined time has elapsed since an ACK in response to a DCI indicating the CC for transmitting the PUCCH is transmitted. The predetermined time may be, for example, 3 ms later, or until the start of the next slot after 3 ms has elapsed.

[0074] Furthermore, deactivation timing may be specified. Regarding a CC that transmits a PUCCH that was previously enabled, the CC that transmits the PUCCH that was previously enabled may be deactivated when the CC that transmits the PUCCH next becomes enabled.

[0075] 17 is a diagram showing an example of disabling PUCCH carrier switching in an embodiment of the present invention. A disabling command is defined, and a terminal 20 that receives the disabling command may disable PUCCH carrier switching. The disabling command may be notified by MAC-CE or indicated by DCI. Disabling may occur after a predetermined time or period has elapsed after receiving an activation command or after indicating the CC that transmits the PUCCH in MAC-CE and / or DCI. As shown in FIG. 17, during the disabling period, a fallback may be performed to transmit the PUCCH on the PCell, PSCell, or PUCCH-SCell.

[0076] 14 indicates a MAC-CE indicating invalidation, the assumption of the CC transmitting the PUCCH may be switched after a predetermined time has elapsed since an ACK for the MAC-CE is transmitted. The predetermined time may be, for example, 3 ms later, or until the start of the next slot after 3 ms has elapsed.

[0077] In addition, if the instruction for the CC that transmits the PUCCH shown in Figure 15 is a DCI indicating invalidation, the assumption for the CC that transmits the PUCCH may be switched before transmitting the PUCCH / PUSCH that transmits the ACK / NACK for the DCI.

[0078] 16 is a DCI indicating invalidation, the assumed CC for transmitting the PUCCH may be switched after a predetermined time has elapsed since an ACK for the DCI was transmitted. The predetermined time may be, for example, 3 ms later, or until the start of the next slot after 3 ms has elapsed.

[0079] PUCCH power control is configured by pucch-PowerControl included in PUCCH-Config, which is an RRC information element, and PUCCH spatial relation included in PUCCH resource. Multiple sets of P0, α, and path loss RS may be configured in pucch-PowerControl, and an ID indicating one of the sets may be indicated in PUCCH spatial relation.

[0080] When PUCCH carrier switching is configured, the PUCCH transmission power may be determined using parameters for PUCCH power control configured in the CC (or BWP) that transmits the PUCCH. The parameters may be pucch-PowerControl included in PUCCH-Config and PUCCH spatial relation included in PUCCH resource.

[0081] Regarding OL-PC (Open loop power control) and CL-PC (Closed loop power control) in PUCCH carrier switching, both 1) and 2) shown below may be considered.

[0082] 1) When the carrier for transmitting the PUCCH is dynamically indicated. 2) When the carrier for transmitting the PUCCH is semi-statically indicated. For example, when PUCCH carrier switching is performed only when the PUCCH cannot be transmitted in the slot for transmitting the PUCCH indicated by the HARQ feedback timing indicator.

[0083] 18 is a diagram showing an example (1) of PUCCH transmission power control according to an embodiment of the present invention. When performing PUCCH carrier switching, terminal 20 may use the PUCCH power control parameters of the CC that transmits the PUCCH indicated by the MAC-CE and / or DCI, as shown in FIG. 18. For example, terminal 20 may use the PUCCH power control parameters of the scheduled cell that are indicated by the PRI or information indicating the CC that transmits the PUCCH.

[0084] 19 is a diagram showing an example (2) of PUCCH transmission power control in an embodiment of the present invention. When performing PUCCH carrier switching, as shown in FIG. 19, terminal 20 may use PUCCH power control parameters set for a CC that has received DCI indicating information indicating a CC that transmits PRI or PUCCH. For example, terminal 20 may use PUCCH power control parameters of a scheduling cell that indicates information indicating a CC that transmits PRI or PUCCH. Furthermore, when transmitting PUCCHs scheduled from multiple CCs as shown in FIG. 19, terminal 20 may use PUCCH power control parameters set for a CC that has received the last DCI in the time and frequency directions.

[0085] Furthermore, when performing PUCCH carrier switching, terminal 20 may use the PUCCH power control parameters allocated to the CC on which the PDSCH scheduled by the last DCI is received.

[0086] 20 is a diagram showing an example (3) of PUCCH transmission power control according to an embodiment of the present invention. As shown in FIG. 20, when PUCCH carrier switching is executed or instructed, terminal 20 may reset the accumulated TPC (Transmission Power Control) command value or set the value to 0. For example, the accumulated TPC command value of the PUCCH in CC0 may be a different value from the accumulated TPC command value of the PUCCH in CC1 because the frequencies and propagation paths are different.

[0087] 21 is a diagram showing an example (4) of PUCCH transmission power control according to an embodiment of the present invention. As shown in FIG. 21, terminal 20 may accumulate the TPC command cumulative value before and after PUCCH carrier switching is performed or instructed.

[0088] 22 is a diagram showing an example (5) of PUCCH transmission power control in an embodiment of the present invention. As shown in FIG. 22, a cumulative value of CL-PC may be held for each CC. For example, when a TPC command is instructed for a PUCCH resource of CC0, the cumulative value of the TPC command for the PUCCH of CC0 may be held, and when a TPC command is instructed for a PUCCH resource of CC1, the cumulative value of the TPC command for the PUCCH of CC1 may be held. In the example shown in FIG. 22, the PUCCH of CC1 is not transmitted. Thereafter, when CC1 is instructed as the CC to transmit the PUCCH, the PUCCH may be transmitted using the cumulative value of the TPC commands accumulated in CC1.

[0089] 23 is a diagram showing an example of a spatial relationship in an embodiment of the present invention. As shown in FIG. 23, when transmitting to one base station 10, the path loss differs if the beam, i.e., the spatial relationship (SpatialRelation), differs. Also, when transmitting to two base stations 10, the path loss differs. Therefore, the terminal 20 can hold two accumulated values ​​of CL-PC.

[0090] One spatial relationship is set for each PUCCH resource. Furthermore, closedLoopIndex={i0, i1} is signaled. The PUCCH resource for which i0 is signaled and the PUCCH resource for which i1 is signaled independently hold the accumulated TPC command values ​​of CL-PC.

[0091] 24 is a diagram showing an example (6) of PUCCH transmission power control according to an embodiment of the present invention. Since the PUCCH closedLoopIndex is set in the PUCCH spatialRelation of each PUCCH resource, for a PUCCH resource determined according to the above-described embodiment of the present invention, the PUCCH closedLoopIndex={i0, i1} set in the PUCCH spatialRelation set for the determined PUCCH resource may be used.

[0092] For example, as shown in FIG. 24, when different PUCCH closed loop indexes are set between PUCCH resources before and after PUCCH carrier switching, it may be considered that the PUCCH closed loop index is switched in conjunction with the PUCCH carrier switching.

[0093] Note that the closedLoopIndex and the like are examples of TPC parameters, and other RRC parameters applied to PUCCH power control, such as the values ​​of P0 and α, and PL-RS, may also be set in the terminal 20 using a mechanism similar to that of the closedLoopIndex. For example, when a PUCCH resource is switched due to PUCCH carrier switching, a TPC parameter linked to the PUCCH resource of the switching destination may be applied using the same mechanism.

[0094] 25 is a diagram showing an example (1) of UCI multiplexing according to an embodiment of the present invention. As shown in FIG. 25, when the HARQ feedback timing indicator field indicates that multiple UCIs are to be transmitted in the same slot or sub-slot, the multiple UCIs may be multiplexed and transmitted in the same PUCCH resource. Hereinafter, "slot" may be replaced with "sub-slot."

[0095] Hereinafter, a case will be described in which PUCCH carrier switching is dynamically performed in consideration of the numerology or subcarrier spacing (SCS) of the CC that transmits the PUCCH.

[0096] Figure 26 is a diagram showing an example (2) of UCI multiplexing in an embodiment of the present invention. As shown in Figure 26, when CC0 and CC1 have different SCSs and the SCS of the CC transmitting the PUCCH is smaller, the two UCIs are not transmitted in the same slot. HARQ-ACK transmission is indicated in slot #n in CC0, and HARQ-ACK transmission is indicated in slot #m in CC1. In the case shown in Figure 26, the PUCCH may be transmitted in slot #n of CC0.

[0097] Figure 27 is a diagram showing an example (3) of UCI multiplexing in an embodiment of the present invention. As shown in Figure 27, when CC0 and CC1 have different SCSs and the SCS of the CC transmitting the PUCCH is smaller, the two UCIs are not transmitted in the same slot. HARQ-ACK transmission is indicated in slot #n in CC0, and HARQ-ACK transmission is indicated in slot #m+1 in CC1. In the case shown in Figure 27, PUCCH may be transmitted in slot #n of CC0.

[0098] Figure 28 is a diagram showing an example (4) of UCI multiplexing in an embodiment of the present invention. As shown in Figure 28, when the SCSs of CC0 and CC1 are different and the SCS of the CC transmitting the PUCCH is larger, the two UCIs are not transmitted in the same slot. HARQ-ACK transmission is indicated in slot #n in CC0, and HARQ-ACK transmission is indicated in slot #m in CC1. In the case shown in Figure 28, the PUCCH may be transmitted in slot #m of CC1.

[0099] Figure 29 is a diagram showing an example (5) of UCI multiplexing in an embodiment of the present invention. As shown in Figure 29, when the SCSs of CC0 and CC1 are different and the SCS of the CC transmitting the PUCCH is larger, the two UCIs are not transmitted in the same slot. HARQ-ACK transmission is indicated in slot #n in CC0, and HARQ-ACK transmission is indicated in slot #m+1 in CC1. In the case shown in Figure 29, the PUCCH may be transmitted in slot #m+1 of CC1.

[0100] The conditions under which UCI is multiplexed in the same PUCCH resource may be the conditions shown in 1) to 3) below.

[0101] 1) When at least a portion of the slots or subslots of the PUCCH at the time of indication for each CC overlap. When at least a portion of the slots or subslots of the PUCCH resources overlap in the CC of the PUCCH at the time of indication, the UCI may be multiplexed. It is assumed that the CC of the PUCCH at the time when the PUCCH resource was previously indicated and the CC that actually transmits the PUCCH may be different when PUCCH carrier switching occurs. However, the terminal 20 may use the SCS and slot or subslot of the CC of the PUCCH at the time when the PUCCH resource was indicated or triggered to determine the conditions for multiplexing UCI on the same PUCCH resource and to determine the transmission timing of the UCI.

[0102] 2) When at least a portion of the slot or subslot of the PUCCH at the time of actual transmission overlaps: After the CC transmitting the PUCCH is specified and the CC transmitting the PUCCH is determined, i.e., after PUCCH carrier switching is performed, if at least a portion of the slot or subslot of the CC transmitting the PUCCH overlaps, the UCI may be multiplexed. If there is no overlap with the slot or subslot of the CC transmitting the PUCCH, the UCI may be transmitted without being multiplexed.

[0103] 3) When the slot or sub-slot index values ​​of the HARQ feedback timing indicator of the PUCCH resource indicated in each CC are the same.

[0104] In the above, whether or not to multiplex PUCCHs is determined based on whether or not PUCCH slots or subslots overlap, but terminal 20 may also determine whether or not to multiplex PUCCHs based on whether or not PUCCH resources overlap by at least one symbol in the time domain.

[0105] 30 is a diagram showing an example (1) of a HARQ-ACK offset in an embodiment of the present invention. The timing of transmitting the HARQ-ACK is notified by offset k of the PDSCH reception slot. The UCI of each CC is transmitted by either the PCell, PSCell, or PUCCH-SCell, and it may be determined in advance which CC's UCI is transmitted by which CC's PUCCH. In other words, the CC transmitting the PUCCH does not need to be updated by RRC, MAC-CE, or DCI.

[0106] As shown in Fig. 30, the slot of the CC transmitting the same PUCCH as the receiving slot of the PDSCH or the slot of the CC transmitting the overlapping PUCCH corresponds to k = 0, and the slot of the CC transmitting the PUCCH may be counted until k = K1. For example, if a PUCCH-SCell is not configured and PUCCH carrier switching is not performed, the k value may be counted in the slot of the SpCell that is the same as the receiving slot of the PDSCH.

[0107] For example, when PUCCH-SCell is not configured, UCI of all CCs is transmitted on the PUCCH of the SpCell, so the timing of transmitting HARQ-ACK of all CCs may indicate the offset of the slot or sub-slot of HARQ-ACK in the SpCell, i.e., the CC that transmits the PUCCH.

[0108] For example, the timing of the HARQ-ACK of the PDSCH of the PCell scheduled by the DCI of the PCell may be indicated by the slot or sub-slot offset of the HARQ-ACK in the PCell. Also, the timing of the HARQ-ACK of the PDSCH of the SCell scheduled by the DCI of the SCell may be indicated by the slot or sub-slot offset of the HARQ-ACK in the PCell.

[0109] In PUCCH carrier switching, the CC transmitting the PUCCH may be updated by RRC, MAC-CE, and / or DCI. Regarding the counting and indicating method of the timing of transmitting the HARQ-ACK, as shown in 1)-4) below, the timing of transmitting the HARQ-ACK may be indicated as a slot or subslot in which CC.

[0110] 1) Assuming that the UCI of each CC is transmitted on the PUCCH in either the PCell, the PSCell, or the PUCCH-SCell, a slot or subslot may be indicated in the HARQ feedback timing indicator field. For example, when the HARQ feedback timing indicator field indicates a slot or subslot offset, the offset value may be determined without taking PUCCH carrier switching into consideration.

[0111] 31 is a diagram showing an example (2) of HARQ-ACK offset in an embodiment of the present invention. For example, when PUCCH-SCell is not configured, as shown in FIG. 31, the offset of the slot or subslot for transmitting HARQ-ACK may be indicated on the assumption that PUCCH is transmitted in the PCell or PSCell, i.e., SpCell, in each CC.

[0112] In the example shown in Figure 31, the PUCCH is transmitted in the slot m = 0 in SCells with different SCSs, but the PUCCH may also be transmitted in the slot m = 1. Whether m = 0 or m = 1 may be specified by specifications or may be instructed by a higher layer. When terminal 20 specifies a slot for the PUCCH to be transmitted in a CC with a larger SCS than a CC with a smaller SCS, it may transmit the PUCCH in a slot with a narrower SCS that overlaps at least partially with the slot with the larger SCS. Hereinafter, when the SCS differs between CCs, slots may be specified in a similar manner.

[0113] Furthermore, for example, when a PUCCH-SCell is configured, for HARQ-ACK of a PCell or a PSCell, a slot or subslot for transmitting the HARQ-ACK may be indicated on the assumption that the PUCCH is transmitted in the PCell or the PSCell. For HARQ-ACK of a CC other than the PCell and the PSCell, a slot or subslot for transmitting the HARQ-ACK may be indicated on the assumption that the PUCCH is transmitted in the PUCCH-SCell.

[0114] 2) Figure 32 is a diagram showing an example (3) of a HARQ-ACK offset in an embodiment of the present invention. As shown in Figure 32, a slot or subslot for transmitting a HARQ-ACK may be indicated assuming a PUCCH destination CC. The method for determining the PUCCH destination CC may be determined by a PUCCH switching method in an embodiment of the present invention. Furthermore, a slot or subslot for transmitting a HARQ-ACK may be indicated assuming a PUCCH destination CC at any of the following points: the time of receiving the DCI that triggered the UCI, the time of receiving the PDSCH, and the time of transmitting the PUCCH. The point of time may be specified in the specifications, may be set by a higher layer, or may be the point of time indicated in a UE capability report.

[0115] 3) Figure 33 is a diagram showing an example (4) of HARQ-ACK offset in an embodiment of the present invention. As shown in Figure 33, the UCI of each CC may indicate a slot or subslot in which to transmit HARQ-ACK, assuming that the CC has received PDSCH.

[0116] 4) Assuming the CC that received the DCI that triggered the UCI, the slot or sub-slot in which to transmit the HARQ-ACK may be indicated.

[0117] Figure 34 is a diagram showing an example (5) of the HARQ-ACK offset in an embodiment of the present invention. As shown in Figure 34, the timing of transmitting the HARQ-ACK may be determined by assuming the CC that transmits the PUCCH that was to be transmitted at the time of receiving DCI or PDSCH, and the PUCCH may be transmitted in a slot or subslot that overlaps with this timing. Figure 34 shows an example of the timing of transmitting the HARQ-ACK when the CC that transmits the PUCCH is updated from SCell #2 to SpCell. The k value is counted in the slots in SCell #2.

[0118] Figure 35 is a diagram showing an example (6) of the HARQ-ACK offset in an embodiment of the present invention. As shown in Figure 35, the timing of transmitting the HARQ-ACK may be determined by assuming the CC that will actually transmit the PUCCH, and the PUCCH may be transmitted in a slot or subslot that overlaps with this timing. Figure 35 shows an example of the timing of transmitting the HARQ-ACK when the CC that transmits the PUCCH is updated from SCell #2 to SpCell. The k value is counted in slots in the SpCell.

[0119] Here, conventionally, it was possible to configure PUCCH-Config only for the SpCell and the PUCCH-SCell. Therefore, the configuration of either the SpCell or the PUCCH-SCell may be applied to the cell to which PUCCH carrier switching is transitioned.

[0120] Furthermore, PUCCH-Config may be configured for an SCell other than the SpCell and PUCCH-SCell, limited to terminals 20 configured with PUCCH carrier switching (instruction of the CC for transmitting the PUCCH by RRC, MAC-CE, and / or DCI). However, it may be limited to an SCell corresponding to a CC included in a CC list that is the transition destination of PUCCH carrier switching configured in a higher layer.

[0121] In addition, if PUCCH carrier switching (indicating the CC for transmitting PUCCH via RRC, MAC-CE and / or DCI) is not configured, PUCCH-Config may be configured for up to one additional SCell, or PUCCH-Config may be configured for up to one serving cell per FR.

[0122] The above-described embodiment allows the terminal 20 to flexibly set the carrier to which PUCCH carrier switching is to be performed. It also clarifies PUCCH transmission power control when PUCCH carrier switching is performed. It also clarifies the timing of transmitting HARQ-ACK when PUCCH carrier switching is performed, even when the SCS is different.

[0123] That is, in the wireless communication system, it is possible to determine the timing for transmitting a response related to retransmission control on an uplink control channel.

[0124] (Device Configuration) Next, a functional configuration example 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 executing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only the proposed functions of any of the embodiments.

[0125] <Base Station 10> Fig. 36 is a diagram showing an example of the functional configuration of the base station 10. As shown in Fig. 36, the 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. 36 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention. The transmitting unit 110 and the receiving unit 120 may be called a communication unit.

[0126] 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 transmitter 110 also has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL data, etc. to the terminal 20. The transmitter 110 also transmits the setting information, etc., described in the embodiments.

[0127] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads out the information from the storage device as needed. The control unit 140 performs, for example, overall control of the base station 10, including control related to signal transmission and reception. Note that the functional unit related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and the functional unit related to signal reception in the control unit 140 may be included in the receiving unit 120. The transmitting unit 110 and the receiving unit 120 may also be called a transmitter and a receiver, respectively.

[0128] <Terminal 20> Fig. 37 is a diagram showing an example of the functional configuration of the terminal 20. As shown in Fig. 37, 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. 37 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention. The transmitting unit 210 and the receiving unit 220 may be called a communication unit.

[0129] The transmitter 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals. The transmitter 210 also transmits HARQ-ACK, and the receiver 220 receives the setting information and the like described in the embodiments.

[0130] The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220 in a storage device and reads it out from the storage device as needed. The setting unit 230 also stores setting information that is set in advance. The control unit 240 performs overall control of the terminal 20, including control related to signal transmission and reception. Note that the function unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and the function unit related to signal reception in the control unit 240 may be included in the receiving unit 220. The transmitting unit 210 and the receiving unit 220 may also be called a transmitter and a receiver, respectively.

[0131] (Hardware Configuration) The block diagrams (FIGS. 36 and 37) 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 a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0132] Functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0133] For example, the base station 10, the terminal 20, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 38 is a diagram illustrating an example of the hardware configuration of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The base station 10 and the terminal 20 described above 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.

[0134] In the following description, the term "apparatus" can be interpreted 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 apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0135] Each function in the base station 10 and the terminal 20 is realized by loading specified 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.

[0136] The processor 1001 controls the entire computer by running, for example, an operating system. 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.

[0137] 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. 36 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 37 may be implemented by a control program stored in the storage device 1002 and running on 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 also be transmitted from a network via a telecommunications line.

[0138] 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 read-only memory (EPROM), an electrically erasable programmable read-only memory (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.

[0139] 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 (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0140] The communication device 1004 is hardware (transmission / reception 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 a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, a transmission / reception antenna, an amplifier unit, a transmission / reception unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmission / reception unit may be implemented as a transmission unit and a reception unit that are physically or logically separated.

[0141] The input device 1005 is an input device (e.g., 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 (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0142] 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.

[0143] Furthermore, the base station 10 and the 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, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0144] (Summary of embodiment) As described above, according to the embodiment of the present invention, there is provided a terminal having a receiving unit that receives control information and data from a base station, a control unit that determines a carrier for transmitting an uplink control channel based on the control information, and a transmitting unit that transmits information related to retransmission control of the data on the determined carrier to the base station via the uplink control channel, wherein the control unit determines the timing for transmitting the information related to retransmission control of the data by assuming the carrier for transmitting the uplink control channel.

[0145] With the above configuration, even if the SCS is different, it is possible to clarify the timing of transmitting HARQ-ACK when PUCCH carrier switching is performed in terminal 20. In other words, it is possible to determine the timing of transmitting a response related to retransmission control on an uplink control channel in a wireless communication system.

[0146] The control unit may determine the timing of transmitting the information related to the retransmission control of the data based on one of predefined carriers. With this configuration, in the terminal 20, the timing of transmitting the HARQ-ACK when PUCCH carrier switching is performed can be clarified even when the SCS is different.

[0147] The control unit may determine the timing of transmitting the information related to the retransmission control of the data based on the carrier that transmits the uplink control channel indicated by the control information. With this configuration, the timing of transmitting HARQ-ACK when PUCCH carrier switching is performed in terminal 20 can be clarified even when SCSs are different.

[0148] The control unit may determine the timing of transmitting information related to retransmission control of the data based on the carrier on which the receiving unit received the control information and the data. With this configuration, it is possible to clarify the timing of transmitting HARQ-ACK when PUCCH carrier switching is performed in terminal 20 even when SCSs are different.

[0149] The control unit may set a parameter for transmitting the uplink control channel to a carrier that transmits the uplink control channel indicated by the control information. With this configuration, the terminal 20 can flexibly set a carrier to which PUCCH carrier switching is to be performed.

[0150] Furthermore, according to an embodiment of the present invention, there is provided a communication method in which a terminal executes a receiving procedure for receiving control information and data from a base station, a control procedure for determining a carrier for transmitting an uplink control channel based on the control information, a transmitting procedure for transmitting information related to retransmission control of the data to the base station via the uplink control channel on the determined carrier, and a procedure for determining the timing for transmitting the information related to retransmission control of the data, assuming the carrier for transmitting the uplink control channel.

[0151] With the above configuration, even if the SCS is different, it is possible to clarify the timing of transmitting HARQ-ACK when PUCCH carrier switching is performed in terminal 20. In other words, it is possible to determine the timing of transmitting a response related to retransmission control on an uplink control channel in a wireless communication system.

[0152] (Supplementary Notes on the Embodiments) Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, 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 (as long as there is no contradiction). Boundaries between functional units or processing units in functional block diagrams do not necessarily correspond to 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 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, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor of the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor of the terminal 20 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

[0153] 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., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the 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.

[0154] 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 (New Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), or other suitable systems, and next-generation systems enhanced based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G, etc.) may also be applied.

[0155] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be rearranged 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.

[0156] In this specification, a specific operation described as being performed by the base station 10 may 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 or an S-GW). 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 (such as an MME and an S-GW).

[0157] 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.

[0158] 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.

[0159] In the present disclosure, the determination may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0160] 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.

[0161] 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.

[0162] 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.

[0163] Note that terms described 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). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0164] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0165] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0166] 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.

[0167] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station," "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. A base station may also be referred to by terms such as a macrocell, a small cell, a femtocell, and a picocell.

[0168] 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 partitioned into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a remote radio head (RRH)). The terms "cell" or "sector" refer to part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage area.

[0169] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.

[0170] 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.

[0171] 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 body, the mobile body itself, etc. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (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 also include devices that do 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.

[0172] 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 multiple terminals 20 (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this 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.

[0173] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station may be configured to have the functions of the user terminal described above.

[0174] 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.

[0175] 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 one or more wires, cables, and / or 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.

[0176] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0177] 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."

[0178] 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.

[0179] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0180] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0181] 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.

[0182] Numerology may be communication parameters that apply to the transmission and / or 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, specific windowing operations performed by the transceiver in the time domain, etc.

[0183] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may be a time unit based on numerology.

[0184] 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.

[0185] 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.

[0186] 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 ms) in existing LTE, a period shorter than 1 ms (for example, 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.

[0187] 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.

[0188] 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.

[0189] 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.

[0190] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), 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 or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0191] 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 greater than or equal to 1 ms.

[0192] A resource block (RB) is a resource allocation unit in the time domain and the 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 the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0193] 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.

[0194] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0195] 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.

[0196] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (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 BWP and numbered within the BWP.

[0197] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be set for the terminal 20 within one carrier.

[0198] At least one of the configured BWPs may be active, and the terminal 20 may not expect to transmit or receive a predetermined signal / channel outside the active BWP. Note that the terms "cell," "carrier," and the like in this disclosure may be read as "BWP."

[0199] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various changes may be made to 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.

[0200] 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.

[0201] 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."

[0202] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0203] 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.

[0204] REFERENCE SIGNS LIST 10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Controller 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Controller 30 Core network 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device

Claims

1. A receiving unit that receives DCI (Downlink Control Information) and PDSCH (Physical Downlink Shared Channel) that specify a cell different from the primary cell as the transmission destination cell of the PUCCH (Physical Uplink Control Channel) from a base station, a control unit that determines, based on the DCI, the cell different from the primary cell as the transmission destination cell of the PUCCH, and a transmission unit that transmits information related to retransmission control corresponding to the PDSCH to the base station in the transmission destination cell of the PUCCH, wherein the control unit determines, assuming that the PUCCH is transmitted in the transmission destination cell of the PUCCH, a slot for transmitting information related to retransmission control corresponding to the PDSCH in the transmission destination cell of the PUCCH. A terminal.

2. The terminal according to claim 1, wherein the transmission unit transmits to the base station a terminal capability indicating whether or not PUCCH cell switching by the DCI is supported.

3. A transmission unit that transmits DCI (Downlink Control Information) and PDSCH (Physical Downlink Shared Channel) that specify a cell different from the primary cell as the transmission destination cell of the PUCCH (Physical Uplink Control Channel) to a terminal, a control unit that assumes, based on the DCI, the cell different from the primary cell as the reception destination cell of the PUCCH, and a receiving unit that receives information related to retransmission control corresponding to the PDSCH from the terminal in the reception destination cell of the PUCCH, wherein the control unit determines, assuming that the PUCCH is received in the reception destination cell of the PUCCH, a slot for receiving information related to retransmission control corresponding to the PDSCH in the reception destination cell of the PUCCH. A base station.

4. A communication system having a terminal and a base station, wherein the terminal is A receiving unit that receives DCI (Downlink Control Information) and PDSCH (Physical Downlink Shared Channel) that specify a cell different from the primary cell as the destination cell of the PUCCH (Physical Uplink Control Channel) from the base station, A control unit that determines, based on the DCI, the cell different from the primary cell as the destination cell of the PUCCH, A transmitting unit that transmits information related to retransmission control corresponding to the PDSCH to the base station in the destination cell of the PUCCH, and The control unit determines a slot for transmitting information related to retransmission control corresponding to the PDSCH in the destination cell of the PUCCH, assuming that the PUCCH is transmitted in the destination cell of the PUCCH. The base station A transmitting unit that transmits the DCI and the PDSCH to the terminal, A control unit that assumes, based on the DCI, a cell different from the primary cell as the reception destination cell of the PUCCH, and A receiving unit that receives information related to retransmission control corresponding to the PDSCH from the terminal in the reception destination cell of the PUCCH, and The control unit determines a slot for receiving information related to retransmission control corresponding to the PDSCH in the reception destination cell of the PUCCH, assuming that the PUCCH is received in the reception destination cell of the PUCCH. A communication system.

5. A procedure for a terminal to receive DCI (Downlink Control Information) and PDSCH (Physical Downlink Shared Channel) that specify a cell different from the primary cell as the destination cell of the PUCCH (Physical Uplink Control Channel) from a base station, A procedure for determining, based on the DCI, the cell different from the primary cell as the destination cell of the PUCCH, A procedure for transmitting information related to retransmission control corresponding to the PDSCH to the base station in the destination cell of the PUCCH, and A communication method in which the terminal executes a procedure for determining a slot for transmitting information related to retransmission control corresponding to the PDSCH in the destination cell of the PUCCH, assuming that the PUCCH is transmitted in the destination cell of the PUCCH.