Terminal, wireless communication method, base station and system

Abstract

A terminal according to an embodiment of the present disclosure comprises: a reception unit that receives downlink control information (DCI) that schedules a multicast downlink shared channel; and a control unit that, on the basis of the DCI, controls transmission of Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) to the downlink shared channel, the DCI being common to a plurality of terminals. According to the embodiment of the present disclosure, a PDSCH using multicasting can be appropriately received.

Description

[Technical field]

[0001] The present disclosure relates to a terminal and a wireless communication method in a next-generation mobile communication system. 、 base station and systems Regarding. [Background technology]

[0002] In the Universal Mobile Telecommunications System (UMTS) network, Long Term Evolution (LTE) has been specified for the purpose of achieving higher data rates and lower latency (Non-Patent Document 1). In addition, LTE-Advanced (3GPP Rel. 10-14) has been specified for the purpose of achieving higher capacity and greater sophistication of LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

[0003] Successor systems to LTE (e.g., 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 or later, etc.) are also being considered. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010 Summary of the Invention [Problem to be solved by the invention]

[0005] In future wireless communication systems (e.g., NR), it is expected that multiple user terminals (User Equipment (UE)) will communicate in an ultra-high density and high traffic environment.

[0006] In NR, in such an environment, it is assumed that multiple UEs will simultaneously receive the same PDSCH using multicast.

[0007] However, in the NR specifications up to now, the method of receiving the downlink control information (DCI) for scheduling the PDSCH using multicast and the method of transmitting the HARQ-ACK corresponding to the PDSCH using multicast have not been sufficiently considered. If the method cannot be appropriately controlled, there is a risk of degradation of system performance, such as a decrease in throughput.

[0008] Therefore, the present disclosure relates to a terminal and a wireless communication method for appropriately receiving a PDSCH using multicast. 、 base station and systems One of the aims is to provide. [Means for solving the problem]

[0009] A terminal according to an embodiment of the present disclosure transmits a physical uplink control channel (PUCCH) corresponding to a multicast physical downlink shared channel (PDSCH). resourcea control unit that determines a PUCCH resource of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the PDSCH based on the configuration, a PUCCH resource indicator field included in the DCI, and a control channel element (CCE) index of a physical downlink control channel (PDCCH) that transmits the DCI, and the DCI is common to a plurality of terminals. the law of nature , The PUCCH format for the PUCCH resource is a PUCCH format without a demodulation reference signal. It is characterized by: Effect of the Invention

[0010] According to one aspect of the present disclosure, it is possible to properly receive a PDSCH that uses multicast. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing an example of a multicast PDSCH receiving procedure. [Diagram 2] 2A and 2B are diagrams showing an example of an MCS index table for a PDSCH. [Diagram 3] FIG. 3 is a diagram showing an example of a multicast PDSCH receiving procedure. [Figure 4] FIG. 4 is a diagram showing an example of a correspondence relationship between TDRA values ​​and DCI bits for a PUSCH resource. [Diagram 5] FIG. 5 is a diagram illustrating an example of a multicast PDSCH receiving procedure. [Figure 6] FIG. 6 is a diagram illustrating an example of a method for transmitting a HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs. [Figure 7]7A and 7B are diagrams showing an example of detection of HARQ-ACKs transmitted from multiple UEs in a network. [Figure 8] 8A to 8C are diagrams showing an example of a method for transmitting a HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs, and an example of detecting HARQ-ACKs transmitted from multiple UEs in a network. [Figure 9] 9A and 9B are diagrams showing an example of a method for transmitting a HARQ-ACK (PUCCH) corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs. [Figure 10] FIG. 10 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. [Figure 11] FIG. 11 is a diagram illustrating an example of the configuration of a base station according to an embodiment. [Figure 12] FIG. 12 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. [Figure 13] FIG. 13 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] (PUCCH format) In future wireless communication systems (e.g., Rel. 15 and later, 5G, NR, etc.), configurations (formats, also called PUCCH formats (PFs)) for uplink control channels (e.g., PUCCHs) used to transmit uplink control information (UCI) are under consideration. For example, in Rel. 15 NR, support for five types of PFs 0 to 4 is under consideration. Note that the names of the PFs shown below are merely examples, and different names may be used.

[0013] For example, PF0 and PF1 are PFs used for transmitting UCI of up to 2 bits. For example, UCI may be at least one of acknowledgement information (also called hybrid automatic repeat reQuest-Acknowledgement (HARQ-ACK), acknowledgement (ACK) or negative-acknowledgement (NACK), etc.) and scheduling request (SR). PF0 can be assigned to 1 or 2 symbols, and is therefore also called short PUCCH or sequence-based short PUCCH, etc. On the other hand, PF1 can be assigned to 4 to 14 symbols, and is therefore also called long PUCCH, etc. PF0 may transmit a sequence obtained by cyclic shifting a base sequence using a cyclic shift (CS) corresponding to the value of UCI. In PF1, multiple user terminals may be code division multiplexed (CDM) within the same physical resource block (PRB) by time domain block spreading using at least one of CS and time domain (TD)-orthogonal cover code (OCC).

[0014] PF2-4 are PFs used for transmitting UCI of more than 2 bits (e.g., Channel State Information (CSI) or at least one of CSI, HARQ-ACK, and SR). PF2 can be allocated to 1 or 2 symbols, and is therefore also called a short PUCCH, etc. Meanwhile, PF3 and PF4 can be allocated to 4-14 symbols, and are therefore also called long PUCCH, etc. In PF4, multiple user terminals may be CDM-multiplexed using (frequency domain (FD)-OCC) block spreading before DFT.

[0015] For PF1, PF3, and PF4, intra-slot frequency hopping may be applied. symb Then, the length before frequency hopping (first hop) is floor(N symb / 2), and the length after frequency hopping (second hop) is ceil(N symb / 2).

[0016] The waveforms of PF0, PF1, and PF2 may be Cyclic Prefix (CP)-Orthogonal Frequency Division Multiplexing (OFDM). The waveforms of PF3 and PF4 may be Discrete Fourier Transform (DFT)-spread(s)-OFDM.

[0017] The allocation of resources (e.g., PUCCH resources) used for transmitting the uplink control channel is performed using higher layer signaling and / or downlink control information (DCI). Here, the higher layer signaling may be at least one of RRC (Radio Resource Control) signaling, system information (e.g., at least one of RMSI: Remaining Minimum System Information, OSI: Other System Information, MIB: Master Information Block, and SIB: System Information Block), and broadcast information (PBCH: Physical Broadcast Channel).

[0018] In addition, in NR, the number of symbols assigned to PUCCH (which may be called PUCCH assigned symbols, PUCCH symbols, etc.) can be determined as slot-specific, cell-specific, or user terminal-specific, or a combination of these. Since it is expected that the communication distance (coverage) will increase as the number of PUCCH symbols increases, it is assumed that the number of symbols will be increased for user terminals located farther away from a base station (e.g., eNB, gNB).

[0019] (NR Multicast / Broadcast) In NR up to Rel.16, the transmission of at least one of a signal and a channel (hereinafter referred to as a signal / channel) from a network to a UE is basically unicast transmission. In this case, it is assumed that each UE receives the same downlink (DL) data signal / channel (e.g., a downlink shared channel (PDSCH)) transmitted from the network to multiple UEs using multiple reception opportunities (reception occasions) corresponding to multiple beams (or panels) of the network.

[0020] In addition, in an ultra-high density and high traffic environment where many UEs are geographically concentrated (e.g., stadiums, etc.), it is assumed that multiple UEs will receive the same signal / channel simultaneously. In such a case, if multiple UEs are present in the same area and each UE receives the same signal / channel by unicast, it is considered that the reliability of communication can be ensured, but the efficiency of resource utilization will decrease.

[0021] On the other hand, there are also use cases (e.g., television, radio, etc.) where the same DL data signal / channel is transmitted to multiple UEs via multicast (broadcast). However, in such use cases, the NW does not check the reception of the DL data signal / channel from each UE, making it difficult to ensure reliability.

[0022] Therefore, the inventors have come up with a method for a UE to receive downlink control information (DCI) that schedules a PDSCH using multicast, and a method for transmitting delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.) corresponding to a PDSCH using multicast.

[0023] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0024] (Wireless communication method) A multicast / broadcast may be set from the NW to a plurality of UEs. The multicast / broadcast may be set by using higher layer signaling.

[0025] A UE configured with multicast / broadcast may receive a PDSCH scheduled by a blindly detected (received) DCI (PDCCH) in at least one of a downlink control channel (PDCCH) monitoring occasion, a search space, and a control resource set (CORESET) corresponding to the multicast / broadcast. The PDSCH may be called a PDSCH using multicast.

[0026] Furthermore, a UE configured with multicast / broadcast may transmit a HARQ-ACK / NACK for a PDSCH using multicast using a PUCCH or a PUSCH.

[0027] The HARQ-ACK / NACK may be transmitted as one bit of HARQ-ACK / NACK for each transport block (TB) / codeword (CW) of a PDSCH using multicast, or as one bit of HARQ-ACK / NACK for multiple TBs / CWs.

[0028] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, and the like, or a combination of these.

[0029] The MAC signaling may be, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0030] The physical layer signaling may be, for example, Downlink Control Information (DCI).

[0031] In the present disclosure, multicast may be interchangeably read as broadcast (notification information). Furthermore, a PDSCH using multicast may be interchangeably read as a PDSCH common to multiple UEs, a common PDSCH, a shared PDSCH, a multicast PDSCH, a broadcast (notification) PDSCH, and the like.

[0032] In the present disclosure, A / B may mean at least one of A and B.

[0033] In this disclosure, the PUCCH / PUSCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH may be simply referred to as HARQ-ACK transmission resources.

[0034] In this disclosure, each of the multiple UEs may be referred to as a respective UE, or simply as a UE.

[0035] <First embodiment> For multiple HARQ-ACK transmission resources assigned to multiple UEs corresponding to a multicast downlink shared channel (PDSCH), each UE may transmit HARQ-ACK using mutually orthogonal (non-overlapping) UL resources (orthogonal UL resources). In other words, each UE may be assigned a UE-specific or dedicated PUCCH / PUSCH resource for HARQ-ACK transmission. This case will be described in detail in the second and third embodiments below.

[0036] Also, for multiple HARQ-ACK transmission resources assigned to multiple UEs corresponding to a downlink shared channel (PDSCH) using multicast, each UE may transmit HARQ-ACK using UL resources (non-orthogonal UL resources) that are not orthogonal to each other (at least partially overlapping). In other words, each UE may not be assigned a PUCCH / PUSCH resource for transmitting HARQ-ACK that is individual to the UE, but may be assigned a PUCCH / PUSCH resource for transmitting HARQ-ACK that overlaps (is common) among multiple UEs. This case will be described in detail in the third and fourth embodiments below.

[0037] <Second embodiment> In the second embodiment, a case will be described in which multiple UEs transmit HARQ-ACK using orthogonal UL resources. Specifically, the case will be described in which each UE receives UE-specific DCI, and each DCI schedules a PDSCH (multicast PDSCH) common to multiple UEs, and indicates a PUCCH / PUSCH resource for transmitting a UE-specific HARQ-ACK corresponding to the multicast PDSCH.

[0038] Fig. 1 is a diagram showing an example of a multicast PDSCH reception procedure. In Fig. 1, a certain UE monitors a UE-specific DCI (at least DCI1 among DCI0-3), receives a multicast PDSCH, and transmits a HARQ-ACK corresponding to the multicast PDSCH using a UE-specific PUCCH resource (at least PUCCH1 among PUCCH0-3).

[0039] Note that the numbers of DCI, PDSCH, and PUCCH resources and the time / frequency allocation positions shown in FIG. 1 are merely an example, and the present invention is not limited to this example.

[0040] Search Space The search space for monitoring UE-specific DCI may be a common search space or a UE specific search space, or may be a search space (or a control resource set (CORESET)) dedicated to a multicast / broadcast schedule defined in a specification.

[0041] 《RNTI》 The UE-specific DCI may be cyclic redundancy check (CRC) scrambled by a UE-specific Radio Network Temporary Identifier (RNTI) (e.g., a cell (C-) RNTI) or may be CRC-scrambled by a UE-common RNTI. Also, the UE-specific DCI may be CRC-scrambled by an RNTI dedicated to a multicast / broadcast schedule defined in a specification.

[0042] PUCCH / PUSCH Resources The PUCCH resource for transmitting the HARQ-ACK may be indicated by at least one of a PUCCH resource indicator (PUCCH Resource Indicator (PRI)) included in a DCI (scheduling DCI) that schedules a multicast PDSCH and a control channel element (CCE) index (e.g., the first CCE index) of a PDCCH that carries the DCI. In addition, N (N is an integer, e.g., 16) PUCCH resources are configured for each UE by higher layer signaling (e.g., RRC signaling), and the PUCCH resource for transmitting the HARQ-ACK may be specified by at least one of a PRI included in the scheduling DCI and a CCE index of the PDCCH of the DCI from among the N PUCCH resources.

[0043] The PUSCH resources for transmitting the HARQ-ACK may be specified by at least one of a Time Domain Resource Assignment (TDRA) field and a Frequency Domain Resource Assignment (FDRA) field included in the DCI, where M (M is an integer) time / frequency resources are configured for each UE by higher layer signaling (e.g., RRC signaling).

[0044] DCI Format The multicast PDSCH may be scheduled by DCI format 1_1 / 1_0, or may be scheduled by a DCI format dedicated to the multicast PDSCH.

[0045] When the multicast PDSCH is scheduled by DCI format 1_1 / 1_0, the conventional DCI format can be used, and therefore the implementation of the UE is easy. Also, when the multicast PDSCH is scheduled by DCI format 1_0, which has fewer UE-specific fields, the multicast PDSCH, which is a PDSCH common to all UEs, can be efficiently scheduled.

[0046] When the multicast PDSCH is scheduled by a DCI format dedicated to the multicast PDSCH, the UE may report UE capability information (UE Capability) regarding whether the multicast PDSCH-dedicated DCI format is supported to the network (NW, for example, gNB). In this case, the number of combinations of DCI sizes (payload size, number of bits) increases, the number of blind detections of DCI performed by the UE increases, and the complexity of UE operations increases. Therefore, only UEs that support the DCI format may monitor the DCI format.

[0047] Furthermore, when a multicast PDSCH is scheduled by DCI format 1_0, reception of the multicast PDSCH is set by higher layer signaling, and the DCI is CRC scrambled with an RNTI dedicated to the multicast / broadcast schedule, the UE may control reception processing of the multicast PDSCH by replacing field values ​​included in the DCI format 1_0 with parameters for multicast without changing the size of the DCI format 1_0. In this case, the UE may use DCI format 1_0 that is not CRC scrambled with an RNTI dedicated to the multicast / broadcast schedule for purposes other than scheduling the multicast PDSCH.

[0048] In addition, when a multicast PDSCH is scheduled by DCI format 1_0 and reception of the multicast PDSCH is configured by higher layer signaling, the UE may control the reception processing of the multicast PDSCH by replacing the fields included in the DCI format 1_0 with parameters for multicast without changing the size of the DCI format 1_0.

[0049] When a multicast PDSCH is scheduled by DCI format 1_0, the UE may use at least one of the following fields included in DCI format 1_0 for scheduling the multicast PDSCH: a DCI format identifier field, a frequency domain resource allocation field, a time domain resource allocation field, a virtual resource block (VRB) to physical resource block (PRB) mapping field, a new data indicator (NDI) field, a redundancy version (RV) field, a HARQ process number field, a downlink assignment index (DAI) field, a Transmission Power Control (TPC) command field for the scheduled PUCCH, a PRI field, and a PDSCH-to-HARQ_feedback timing indicator field.

[0050] Also, when the multicast PDSCH is scheduled by DCI format 1_0, the UE may not use the Modulation and coding scheme (MCS) field among the fields included in DCI format 1_0 to schedule the multicast PDSCH. In this case, the MCS parameter or MCS index of the multicast PDSCH may be a certain value.

[0051] The certain value may be specified in a specification. For example, the certain value may be the smallest (or the Xth smallest) MCS index in an MCS index table for PDSCH that is predefined in a specification. The certain value may be notified to the UE by higher layer signaling. The certain value may be a value reported to the NW by UE capability information.

[0052] Also, in consideration of the reliability of multicast, it is considered that 256 quadrature amplitude modulation (QAM) is not used for multicast PDSCH. In this case, a table that does not include 256 QAM parameters (MCS index table 1 for PDSCH (FIG. 2A)) and a table that includes 256 QAM parameters (MCS index table 2 for PDSCH (FIG. 2B)) may be specified in the specifications.

[0053] In this case, the UE may determine at least one of a modulation order, a target code rate, and a spectral efficiency from the MCS index of the multicast PDSCH by using MCS index table 1. Specifically, in scheduling the multicast PDSCH, the UE may refer to MCS index table 1 if the higher layer parameters (MCS-Table-PDSCH, mcs-Table) are not set to MCS index table 2 (table for 256QAM, 'qam256') and DCI that is CRC scrambled by the C-RNTI is received.

[0054] Note that the values ​​in the MCS index table for PDSCH shown in Figures 2A and 2B are merely examples and are not limited to these. Also, the MCS index table may be interpreted as a table that does not include modulation orders of a specific value (e.g., 8) or more.

[0055] The UE may not use the MCS field, among the fields included in DCI format 1_0, for scheduling the multicast PDSCH, regardless of whether or not a DCI format dedicated to the multicast PDSCH schedule is specified, whether or not an RNTI dedicated to the multicast PDSCH schedule is specified, and whether or not a field included in DCI format 1_0 is reinterpreted. In this case, the UE can distinguish between DCI for scheduling the multicast PDSCH and DCI for scheduling other PDSCHs based on the presence or absence of the MCS field, and can utilize the fields not used in the DCI for scheduling the multicast PDSCH for other purposes (for example, increasing the bit field of the TDRA / FDRA field).

[0056] <Third embodiment> In the third embodiment, a case will be described in which multiple UEs transmit HARQ-ACK using orthogonal UL resources. Specifically, each UE receives DCI common to multiple UEs, and the DCI schedules a PDSCH (multicast PDSCH) common to multiple UEs, and indicates PUCCH / PUSCH resources for transmitting HARQ-ACK for each UE corresponding to the multicast PDSCH. In this embodiment, the above-mentioned second embodiment may be applied to some UEs among multiple UEs.

[0057] Fig. 3 is a diagram showing an example of a multicast PDSCH reception procedure. In Fig. 3, a certain UE monitors a DCI (DCI1) common to UEs, receives a multicast PDSCH, and transmits a HARQ-ACK corresponding to the multicast PDSCH using a UE-specific PUCCH resource (at least PUCCH1 among PUCCH0-3).

[0058] Note that the numbers of DCI, PDSCH, and PUCCH resources and the time / frequency allocation positions shown in FIG. 3 are merely an example, and the present invention is not limited to this example.

[0059] Search Space The search space for monitoring the UE-common DCI may be a common search space or a UE specific search space, or may be a search space (or a control resource set (CORESET)) dedicated to a multicast / broadcast schedule defined in a specification.

[0060] 《RNTI》 The UE-common DCI may be CRC-scrambled with a UE-specific Radio Network Temporary Identifier (RNTI) (e.g., a cell (C-) RNTI) or may be CRC-scrambled with a UE-common RNTI. The UE-common RNTI may be a newly defined RNTI. Also, the UE-specific DCI may be CRC-scrambled with an RNTI dedicated to a multicast / broadcast schedule defined in a specification.

[0061] PUSCH / PUCCH Resources The PUSCH resources for transmitting the HARQ-ACK may be specified by at least one of the TDRA field and the FDRA field included in the DCI, where M (M is an integer) time / frequency resources are configured for each UE by higher layer signaling (e.g., RRC signaling).

[0062] The PUCCH resource for transmitting the HARQ-ACK may be indicated by at least one of the PRI included in the DCI (scheduling DCI) that schedules the multicast PDSCH and the CCE index (e.g., the first CCE index) of the PDCCH that carries the DCI. In addition, N (N is an integer, e.g., 16) PUCCH resources are configured for each UE by higher layer signaling (e.g., RRC signaling), and the PUCCH resource for transmitting the HARQ-ACK may be specified by at least one of the PRI included in the scheduling DCI and the CCE index of the PDCCH that carries the DCI from among the N PUCCH resources.

[0063] However, when a UE performs the above-mentioned method of determining PUSCH / PUCCH resources for transmitting HARQ-ACK corresponding to a multicast PDSCH, there is a concern that the PUSCH / PUCCH resources of multiple UEs may overlap. In the following, a method of avoiding the overlap of the PUSCH / PUCCH resources of multiple UEs will be described.

[0064] The UE may transmit a HARQ-ACK corresponding to the multicast PDSCH using a PUSCH based on a configured grant. In the present disclosure, the PUSCH based on the configured grant may be read as a configured grant-based PUSCH, a configured grant PUSCH, a PUSCH using a configured grant, or the like. In this case, the UE may transmit a HARQ-ACK corresponding to the multicast PDSCH using a PUSCH resource configured by the configured grant after the configured grant is configured. In addition, the UE may assume that the configured grant (and the PUSCH resource) is configured when the reception of the multicast PDSCH is configured.

[0065] At this time, for HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may use the value of the HARQ-ACK timing indicator (PDSCH-to-HARQ_feedback timing indicator) field included in DCI format 1_0. When a PUSCH resource is configured by a configuration grant in a time domain (e.g., a slot) indicated by the HARQ-ACK timing indicator field, the UE may transmit a HARQ-ACK corresponding to the multicast PDSCH.

[0066] Furthermore, if a PUSCH resource is not configured by a configuration grant in the time region indicated by the HARQ-ACK timing indicator field, the UE does not need to transmit an HARQ-ACK corresponding to a multicast PDSCH.

[0067] In addition, if a PUSCH resource is not configured by the configuration grant in the time domain indicated by the HARQ-ACK timing indicator field, the UE may retain (store) the HARQ-ACK bit corresponding to the multicast PDSCH and transmit a HARQ-ACK corresponding to the multicast PDSCH in the PUSCH resource by the configuration grant at the next transmission opportunity (timing).

[0068] In addition, if the PUSCH resource by the configuration grant is not configured in the time domain indicated by the HARQ-ACK timing indicator field, the UE may drop the HARQ-ACK bit corresponding to the multicast PDSCH. The UE may generate and transmit a HARQ-ACK corresponding to a new multicast PDSCH in the PUSCH resource by the configuration grant at the next transmission opportunity (timing).

[0069] Also, the UE may be configured with a PUCCH resource for transmitting a HARQ-ACK corresponding to a multicast PDSCH. The PUCCH resource may be configured with a PUCCH resource for transmitting a HARQ-ACK corresponding to a unicast PDSCH (at least one of a PUCCH format, a starting symbol, a duration (number of symbols), a physical resource block (PRB) index (a first PRB index, for example, at least one of a starting PRB index and a second hop PRB index), and an initial cyclic shift (CS) index). The PUCCH resource may be configured in the UE by higher layer signaling.

[0070] In addition, the UE may be configured / activated with periodic or semi-persistent PUCCH resources (which may be referred to as configured PUCCH resources) for HARQ-ACK transmission corresponding to the multicast PDSCH. In other words, if the multicast PDSCH is configured, the UE may assume that the PUCCH resources for HARQ-ACK transmission are configured PUCCH resources. The UE may be configured with the configured PUCCH resources by higher layer signaling. The configuration of the configured PUCCH resources may include a parameter indicating the period of the PUCCH.

[0071] The UE may use the configured PUCCH resource to transmit a HARQ-ACK corresponding to the multicast PDSCH.

[0072] At this time, for the HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may use the value of the HARQ-ACK timing indicator field included in DCI format 1_0. When a configured PUCCH resource for the HARQ-ACK transmission corresponding to the multicast PDSCH is configured in the time domain (e.g., slot) indicated by the HARQ-ACK timing indicator field, the UE may transmit the HARQ-ACK corresponding to the multicast PDSCH.

[0073] Furthermore, if no configured PUCCH resources for transmitting a HARQ-ACK corresponding to a multicast PDSCH are configured in the time domain indicated by the HARQ-ACK timing indicator field, the UE does not need to transmit a HARQ-ACK corresponding to a multicast PDSCH.

[0074] In addition, if no PUCCH resource is configured for transmitting a HARQ-ACK corresponding to a multicast PDSCH in the time domain indicated by the HARQ-ACK timing indicator field, the UE may retain (store) the HARQ-ACK bit corresponding to the multicast PDSCH and transmit the HARQ-ACK corresponding to the multicast PDSCH in the PUCCH resource configured for transmitting a HARQ-ACK corresponding to the multicast PDSCH at the next transmission opportunity (timing).

[0075] In addition, if the configured PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH is not configured in the time domain indicated by the HARQ-ACK timing indicator field, the UE may drop the HARQ-ACK bit corresponding to the multicast PDSCH. The UE may generate and transmit a new HARQ-ACK corresponding to the multicast PDSCH in the configured PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH at the next transmission opportunity (timing).

[0076] In addition, in the present disclosure, a PUSCH resource by a configuration grant, a configured PUCCH resource, a resource based on a configuration grant, etc. may be read as interchangeable.

[0077] The PUSCH / PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH may be indicated by a DCI having a CRC scrambled by at least one of a UE index (ID) or an RNTI.

[0078] In this case, the RNTI used to determine the PUSCH / PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH may be a UE-specific RNTI (e.g., C-RNTI). In other words, the RNTI used to determine the PUSCH / PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH may be different from the UE-common RNTI used for CRC scrambling of the DCI for scheduling the multicast PDSCH.

[0079] Furthermore, the PUSCH / PUCCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH may be indicated by at least one of a first method or a second method described below.

[0080] [First method] The UE may convert at least one of the time resource, frequency resource, code, CS, and sequence of the PUCCH resource determined by the PRI / CCE index for the PUCCH resource for HARQ-ACK transmission corresponding to the multicast PDSCH by a certain conversion formula. Also, the UE may assume that at least one of the time resource, frequency resource, code, CS, and sequence of the PUCCH resource determined by the PRI / CCE index for the PUCCH resource for HARQ-ACK transmission corresponding to the multicast PDSCH is converted by a certain conversion formula.

[0081] The conversion formula may be determined based on a UE-specific RNTI (e.g., C-RNTI). For example, the conversion formula may be given by mod({the value of the UE-specific RNTI}, M) (M is an arbitrary integer). Note that mod(X, Y) means the remainder (modulo operation) when X is divided by Y.

[0082] The value M used in the conversion formula may be predefined in a specification or may be determined by higher layer signaling, and the value of M can control the utilization efficiency of PUCCH resources and the possibility of PUCCH resource collision between UEs.

[0083] [Second Method] Also, the UE may assume that the maximum number of PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, which is set by higher layer signaling, is greater than the maximum number specified in Rel. 16. In this case, the UE may determine (be instructed to) the PUCCH resources based on the UE-specific RNTI (e.g., C-RNTI) in addition to the PRI / CCE index.

[0084] The method of indicating the PUCCH resource to the UE is, for example, that the maximum number of PUCCH resources included in the 2nd PUCCH resource set up to Rel.16 is 8, and the UE determines the PUCCH resource by a 3-bit PRI. In this case, when 16 PUCCH resources are configured for the 2nd PUCCH resource set, one PUCCH resource may be determined from the 16 PUCCH resources by using a value derived from mod({UE-specific RNTI value}, M) and PRI. The value M may be a value obtained by dividing the maximum number of PUCCH resources included in the PUCCH resource set by the maximum number of PUCCH resources included in the PUCCH resource set up to Rel.16.

[0085] Furthermore, for a PUSCH resource for transmitting a HARQ-ACK corresponding to a multicast PDSCH, the UE may determine (may be instructed to determine) a TDRA / FDRA for the PUSCH resource based on a conversion formula from the TDRA / FDRA setting values ​​(e.g., a TDRA / FDRA table) for multiple PUSCH resources set by higher layer signaling. The conversion formula may be mod({UE-specific RNTI value}, M) (M is an arbitrary integer).

[0086] Fig. 4 is a diagram showing an example of a correspondence relationship between a TDRA value and a DCI bit for a PUSCH resource. Fig. 4 shows an example of the relationship between a TDRA value and a DCI bit for a PUSCH resource, but a correspondence relationship (table) showing a relationship between a FDRA value and a DCI bit for a PUSCH resource may be set as a setting value, or a correspondence relationship (table) showing a relationship between a TDRA value and a FDRA value for a PUSCH resource and a DCI bit may be set as a setting value.

[0087] The UE may determine the TDRA of the PUSCH resource for transmitting the HARQ-ACK corresponding to the multicast PDSCH by using the correspondence (table) as shown in Fig. 4. The UE may determine the TDRA table of the PUSCH resource to be used from mod ({UE-specific RNTI value}, M) in which multiple TDRA tables are configured by higher layer signaling. Fig. 4 shows the case of M=2, but M and the values ​​written in the table are merely an example and are not limited to this.

[0088] When the value of the UE individual RNTI is expressed in binary notation, the UE may convert the value of the UE individual RNTI into a decimal notation and perform the above modulo operation.

[0089] DCI Format The DCI common to multiple UEs for scheduling the multicast PDSCH may be DCI format 1_1 / 1_0, or may be a DCI format dedicated to the multicast PDSCH.

[0090] When the multicast PDSCH is scheduled by DCI format 1_1 / 1_0, the conventional DCI format can be used, and therefore the implementation of the UE is easy. Also, when the multicast PDSCH is scheduled by DCI format 1_0, which has fewer UE-specific fields, the multicast PDSCH, which is a PDSCH common to all UEs, can be efficiently scheduled.

[0091] When the multicast PDSCH is scheduled by a DCI format dedicated to the multicast PDSCH, the UE may report UE capability information (UE Capability) regarding whether the multicast PDSCH-dedicated DCI format is supported to the network (NW, for example, gNB). In this case, the number of combinations of DCI sizes (payload size, number of bits) increases, the number of blind detections of DCI performed by the UE increases, and the complexity of UE operations increases. Therefore, only UEs that support the DCI format may monitor the DCI format.

[0092] Furthermore, when a multicast PDSCH is scheduled by DCI format 1_0, reception of the multicast PDSCH is set by higher layer signaling, and the DCI is CRC scrambled with an RNTI dedicated to the multicast / broadcast schedule, the UE may control reception processing of the multicast PDSCH by replacing field values ​​included in the DCI format 1_0 with parameters for multicast without changing the size of the DCI format 1_0. In this case, the UE may use DCI format 1_0 that is not CRC scrambled with an RNTI dedicated to the multicast / broadcast schedule for purposes other than scheduling the multicast PDSCH.

[0093] In addition, when a multicast PDSCH is scheduled by DCI format 1_0 and reception of the multicast PDSCH is configured by higher layer signaling, the UE may control the reception processing of the multicast PDSCH by replacing the fields included in the DCI format 1_0 with parameters for multicast without changing the size of the DCI format 1_0.

[0094] When a multicast PDSCH is scheduled by DCI format 1_0, the UE may use at least one of the fields included in DCI format 1_0, namely, a DCI format identifier field, a frequency domain resource allocation field, a time domain resource allocation field, a VRB to PRB mapping field, an NDI field, an RV field, a HARQ process number field, and a downlink assignment index field, for scheduling the multicast PDSCH.

[0095] Furthermore, when the multicast PDSCH is scheduled by DCI format 1_0, the UE may not use the modulation and coding scheme (MCS) field, among the fields included in DCI format 1_0, to schedule the multicast PDSCH. In this case, the method of not using the MCS field to schedule the multicast PDSCH described in the second embodiment may be applied.

[0096] The following describes how to indicate the PUCCH resource, timing (value) and TPC command (value) for each UE using DCI common to all UEs. In Rel.16 NR, the TPC command field for scheduled PUCCH has 2 bits, the PRI field has 3 bits, and the HARQ feedback timing indicator field has 3 bits.

[0097] When a multicast PDSCH is scheduled by DCI format 1_0, the UE may not need to use at least one specific field among the fields included in DCI format 1_0, including the value of the TPC command field for the scheduled PUCCH, the value of the PRI field, and the value of the HARQ feedback timing indicator field.

[0098] In this case, the UE may assume that it will ignore the value of a specific field indicated by DCI format 1_0 and use a certain value. The certain value may be a value determined by a certain conversion formula for the value of the field indicated by DCI format 1_0, or may be a value notified to the UE by UE-specific higher layer signaling.

[0099] The UE may determine the resource / value to be used by assuming bits converted by a certain conversion formula. The conversion method by the conversion formula will be described later in the field (resource / value) conversion method.

[0100] In addition, the UE may use a resource / value indicated by the value of the field indicated by DCI format 1_0, converted by a certain conversion formula.

[0101] The above conversion formula may convert the resource / value using at least a UE-specific index / ID (e.g., C-RNTI). The conversion formula may convert the resource / value using an offset value notified to the UE individually by higher layer signaling. In this case, for example, an offset such as an offset for a PRB index=+p and an offset for an initial CS index=+q (p and q are arbitrary values) may be notified to the UE, and the UE may determine the resource / value (e.g., PRB index, initial CS index, etc.) to be used by adding (or subtracting) the offset value to the index of the PUCCH resource indicated by the PRI / CCE index.

[0102] Regardless of whether or not the UE specifies a DCI format dedicated to the multicast PDSCH schedule, whether or not the UE specifies an RNTI dedicated to the multicast PDSCH schedule, and whether or not the UE replaces the fields included in the DCI format 1_0, the UE may not use at least one of the TPC command field, the PRI field, and the HARQ feedback timing indicator field for the scheduled PUCCH among the fields included in the DCI format 1_0 for scheduling the multicast PDSCH. In this case, the UE can distinguish between the DCI for scheduling the multicast PDSCH and the DCI for the other PDSCHs by the presence or absence of at least one of the TPC command field, the PRI field, and the HARQ feedback timing indicator field for the scheduled PUCCH, and can utilize the fields not used in the DCI for scheduling the multicast PDSCH for other purposes (for example, increasing the bit field of the TDRA / FDRA field).

[0103] When a multicast PDSCH is scheduled by DCI format 1_0, the UE may not use the TPC command field for the scheduled PUCCH among the fields included in DCI format 1_0 to schedule the multicast PDSCH. In this case, the TPC command of the multicast PDSCH may be a certain value.

[0104] That is, the certain value may be ±0. In other words, the UE does not need to assume closed loop (CL)-power control (PC). In addition, the certain value may be specified by a certain bit string (e.g., bits 00) according to the specifications, may be set by higher layer signaling, or may be a value reported to the NW as UE capability information (UE Capability).

[0105] The UE may not use the TPC command field, among the fields included in DCI format 1_0, for scheduling the multicast PDSCH, regardless of whether or not a DCI format dedicated to scheduling the multicast PDSCH is specified, whether or not an RNTI dedicated to scheduling the multicast PDSCH is specified, and whether or not a field included in DCI format 1_0 is reinterpreted. In this case, it is possible to differentiate the DCIs for scheduling the multicast PDSCH and the other PDSCHs, and it is possible to utilize the fields not used in the DCI for scheduling the multicast PDSCH for other purposes (for example, increasing the bit field of the TDRA / FDRA field).

[0106] In this case, the UE may use the TPC command field included in DCI format 1_0, which is not used for scheduling the multicast PDSCH, to switch at least one of the conversion method of the bit field value included in the DCI for each UE and the conversion method of the PUCCH resource. The conversion method of the bit field value included in the DCI for each UE and the conversion method of the PUCCH resource will be described in detail below.

[0107] For example, multiple patterns (eg, four patterns) of bit field (value) / PUCCH resource conversion rules for each UE may be predefined, and the UE may determine one pattern from the multiple patterns using the value of the TPC command field.

[0108] The pattern may be a pattern corresponding to a value obtained by a certain conversion formula. The conversion formula may be determined based on a UE-specific RNTI (e.g., C-RNTI). For example, the conversion formula may be given by mod({UE-specific RNTI value}, M) (M is an arbitrary integer). The value M used in the conversion formula may be specified in advance in a specification, or may be determined by higher layer signaling. The value of M can control the utilization efficiency of PUCCH resources and the possibility of PUCCH resource collision between UEs.

[0109] In the above, a method of using the TPC command field has been described, but a field other than the TPC command field included in DCI format 1_0 (e.g., the PRI field, or the time indicator field from PDSCH to HARQ feedback) may also be used, or higher layer signaling may also be used.

[0110] [Field (resource / value) conversion method] A method for converting a field value (resource / value indicated by) included in a DCI common to multiple UEs into a UE-specific value (resource / value indicated by). The method detailed here can also be applied as appropriate to other embodiments. The conversion rule for the bit field (bit string) shown below may be notified to each UE by UE-specific higher layer signaling, or each UE may determine it based on the UE index (RNTI).

[0111] The UE may determine the resource / value to be used assuming bits converted by a certain conversion formula. For example, if the field value is X bits, the UE may use a value determined by performing at least one of addition, subtraction, and exclusive OR (EXOR) calculation on the X bit value notified by higher layer signaling or the X bit value determined based on the UE index (RNTI) for the field value.

[0112] Also, the UE may rearrange field values ​​included in the DCI common to multiple UEs based on a certain rule to determine the resource / value to be used. The rule may be notified to each UE by higher layer signaling, or the UE may determine the rule based on a UE index (e.g., C-RNTI).

[0113] For example, if each UE is notified of a 3-bit bit field (bit string), and the first UE is notified to rearrange and use the bit string in the order of bit position (123) in the received bit string, and the second UE is notified to rearrange and use the bit string in the order of bit position (321) in the received bit string, then if the bit string received by the first UE and the second UE is

[0110] , the first UE may determine the bit string to use as

[0110] , and the second UE may determine the bit string to use as

[0011] .

[0114] For example, if each UE is notified of a 3-bit bit field (bit string) and the UE makes a decision about the rule based on a UE index (e.g., C-RNTI), a first UE may decide to use the bits in the received bit string in the order of (123), and a second UE may be notified to rearrange the bits in the received bit string and use them in the order of (321).

[0115] The UE may assume that the bit field rearrangement (conversion) rule is specified only for a specific bit field (e.g., a TPC command field for scheduled PUCCH, a PRI field, and a HARQ feedback timing indicator field). In addition, the UE may be configured with the bit field rearrangement rule for each specific bit field separately, or may be configured with a bit rearrangement rule for a variable bit length.

[0116] Furthermore, the UE may determine the number of bits to be used for a field value included in a DCI common to multiple UEs based on a certain rule.

[0117] In this case, for example, when a bit field (bit sequence) is notified to multiple UEs (first UE and second UE), the first UE may assume that all notified bits are used, and the other UE may assume that the most significant (from the left, or the least significant (from the right)) two bits of the notified bits are used. For example, when the bit sequence received by the first UE and the second UE is

[0111] , the first UE may determine that the bit sequence to be used is

[0111] , and the second UE may determine that the received bit sequence is

[11] and determine that the bit sequence to be used is

[0011] .

[0118] Each UE may also determine the resources / values ​​to use for PUCCH by modifying at least one of the following bit fields: DCI bit fields, Minimum / maximum CCE index (PRB / RE index) of the PDCCH carrying DCI, PDCCH (CCE) aggregation level, Search space index, · CORESET index, ·PRG(PRB) index of start / end of PDSCH, · Number of MIMO layers for PDSCH.

[0119] Of the above fields, the fields used by the UE may be set in the UE by higher layer signaling, or may be determined according to a rule based on a UE index (for example, C-RNTI).

[0120] In this case, one UE determines the PUCCH resource to use based on the DCI bit field, while another UE determines the PUCCH resource to use based on both the DCI bit field and the CCE index. Even if a common DCI (DCI bit field) is notified to each UE, each UE can use a different PUCCH resource to transmit an HARQ-ACK.

[0121] According to the third embodiment described above, it is possible to prevent an increase in overhead of DCI notified to a plurality of UEs, while avoiding overlap of resources for transmitting PUSCH / PUCCH, thereby enabling suitable communication.

[0122] <Fourth embodiment> In the fourth embodiment, a case will be described in which multiple UEs transmit HARQ-ACK using non-orthogonal UL resources. Specifically, each UE receives multiple UE common / UE individual DCI, the DCI schedules multiple UE common PDSCH (multicast PDSCH), and each UE is instructed (determines) the time and frequency resources of PUCCH / PUSCH for transmitting HARQ-ACK corresponding to the multicast PDSCH by the DCI. In this embodiment, at least one of the second embodiment and the third embodiment may be applied to some UEs among multiple UEs.

[0123] In this embodiment, a case where each UE receives DCI common to a plurality of UEs will be described, but the contents of this embodiment can also be applied to a case where each UE receives DCI specific to the UE. Also, a case where the PUCCH in this embodiment is a sequence-based PUCCH (e.g., PF0) will be described. The sequence-based PUCCH and the PUCCH without DMRS may be interchangeable.

[0124] Fig. 5 is a diagram showing an example of a multicast PDSCH reception procedure. In Fig. 5, a certain UE monitors a DCI (DCI1) common to each UE, receives a multicast PDSCH, and transmits a HARQ-ACK corresponding to the multicast PDSCH using a PUCCH resource (PUCCH1) common to multiple UEs.

[0125] Note that the DCI, the number of PUCCH resources, and the time / frequency allocation positions shown in FIG. 5 are merely an example, and the present invention is not limited to this example.

[0126] In transmitting HARQ-ACK, two (ACK and NACK) resources (PRB or RE) are reserved to transmit 1-bit HARQ-ACK. When multiple UEs transmit HARQ-ACK corresponding to multicast PDSCH in a common PUCCH resource, the HARQ-ACK resources transmitted by the multiple UEs may overlap depending on the number of UEs or the size of the PUCCH resource. In addition, even if multiple UEs transmit HARQ-ACK in a common PUCCH resource and the HARQ-ACK resources transmitted by the multiple UEs do not overlap, the PUCCH resource will be strained.

[0127] Therefore, a method of overlapping a plurality of HARQ-ACK resources (at least one of ACK resources and NACK resources) used respectively for a plurality of UEs in the time domain and the frequency domain will be described below.

[0128] When transmitting an HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs, the UE may transmit the HARQ-ACK assuming that the ACK resources allocated to multiple UEs overlap.

[0129] In other words, if each UE succeeds in receiving the multicast PDSCH (e.g., demodulation, decoding, etc.) of the HARQ-ACK corresponding to the multicast PDSCH, it transmits an ACK using an overlapping ACK resource, and if the multicast PDSCH receiving process fails, it transmits a NACK in a non-overlapping NACK resource.

[0130] Fig. 6 is a diagram showing an example of a method for transmitting a HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs. One block of resources in Fig. 6 may be a PRB or an RE (or a subcarrier). In Fig. 6, when transmitting a HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs (UE1-4), the ACK resources allocated to each UE are overlapped, and the NACK resources allocated to each UE are not overlapped.

[0131] Note that the number of UEs and the ACK / NACK transmission resources shown in FIG. 6 are merely examples, and are not limited to these examples.

[0132] In this case, the operation of the side receiving HARQ-ACK (ACK and NACK) transmitted from multiple UEs will be described. In the present disclosure, the HARQ-ACK receiving side will be described as a NW, but is not limited to this.

[0133] The NW may detect whether or not multiple UEs have transmitted ACKs based on the received power of ACKs transmitted from multiple UEs in the overlapped resource. When the received power of ACKs transmitted from multiple UEs is equal to or greater than a threshold (greater than the threshold), the NW may determine that all of the multiple UEs have succeeded in receiving the multicast PDSCH, and may not retransmit the multicast PDSCH. The threshold may be a value that allows estimation that all of the multiple UEs have transmitted ACKs. On the other hand, when the received power of ACKs transmitted from multiple UEs is less than a threshold (less than or equal to the threshold), the NW may determine that there is a UE that has failed in receiving the multicast PDSCH, and may retransmit the multicast PDSCH.

[0134] In addition, when ACK resources allocated to multiple UEs are overlapped, NACK resources may not be allocated to multiple UEs. In this case, among the multiple UEs, a UE that has successfully received the multicast PDSCH may transmit an ACK using an ACK transmission resource that overlaps with the ACK transmission resource of another UE, and a UE that has failed in receiving the multicast PDSCH may not transmit a NACK.

[0135] 7A and 7B are diagrams showing an example of HARQ-ACK detection transmitted from multiple UEs in a NW. In FIG. 7A, all of multiple UEs (UE1-4) transmit ACKs using overlapping resources. In this case, when the NW measures the received power of the ACK (FIG. 7B) and estimates that the number of UEs that transmitted the ACK is 4, it determines that all of the multiple UEs have succeeded in receiving the multicast PDSCH, and does not retransmit the multicast PDSCH.

[0136] Note that the number of UEs, ACK / NACK transmission resources, and ACK / NACK reception power by the NW shown in FIG. 7A and FIG. 7B are merely examples, and are not limited to these examples.

[0137] Furthermore, when transmitting an HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs, the UE may transmit the HARQ-ACK assuming that NACK resources allocated to multiple UEs overlap.

[0138] When NACK resources allocated to multiple UEs are overlapped, ACK resources may not be allocated to multiple UEs. In other words, each UE may transmit a NACK in the overlapping resource when the reception process of the multicast PDSCH fails among HARQ-ACKs corresponding to the multicast PDSCH, and may not transmit an ACK when the reception process of the multicast PDSCH succeeds.

[0139] The NW may detect whether or not a plurality of UEs have transmitted NACKs based on the reception power of NACKs transmitted from the plurality of UEs in the overlapping resource. When the NW detects the transmission of NACKs by at least one UE, the NW may determine that there is a UE that has failed in the reception process of the multicast PDSCH, and may retransmit the multicast PDSCH. Furthermore, when the NW does not detect the transmission of NACKs by at least one UE, the NW may determine that all of the plurality of UEs have succeeded in the reception process of the multicast PDSCH, and may not retransmit the multicast PDSCH.

[0140] 8A to 8C are diagrams showing an example of a method for transmitting HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs, and an example of HARQ-ACK detection transmitted from multiple UEs in a network. In FIG. 8A, a UE among multiple UEs (UE1-4) that fails to receive a multicast PDSCH transmits a NACK using a resource that overlaps with the NACK transmission resource of another UE. A UE that succeeds in receiving a multicast PDSCH transmits an ACK.

[0141] At this time, the NW measures the reception power of the NACK, and if it estimates that there is at least one UE that has transmitted a NACK, it determines that one of the UEs has failed in the reception process of the multicast PDSCH, and retransmits the multicast PDSCH. In the example shown in Fig. 8B, the NW measures the reception power of the NACK, estimates that there is no UE that has transmitted a NACK, and does not retransmit the multicast PDSCH. In the example shown in Fig. 8C, the NW measures the reception power of the NACK, and if it estimates that there is one or more UEs that have transmitted a NACK, it retransmits the multicast PDSCH.

[0142] In FIG. 8A, the NACK resource for the multicast PDSCH may be allocated, and the ACK resource may not be allocated. In this case, among the multiple UEs (UE1-4), a UE that fails to receive the multicast PDSCH transmits a NACK using a resource that overlaps with the NACK transmission resource of another UE. A UE that succeeds in receiving the multicast PDSCH does not transmit an ACK.

[0143] Note that the number of UEs, ACK / NACK transmission resources, and ACK / NACK reception power by the NW shown in Figures 8A to 8C are merely examples, and are not limited to these examples.

[0144] Furthermore, when receiving a multicast PDSCH, each UE may transmit a PUCCH (NACK) if the reception process of the PDSCH fails. In this case, when receiving a multicast PDSCH, each UE may not transmit a PUCCH (ACK) if the reception process of the PDSCH succeeds.

[0145] In this case, the NW can determine the presence of a UE that transmits a NACK based on the received power of the PUCCH. In other words, if the NW does not receive a NACK, the NW can determine that multiple UEs have successfully received the PDSCH. Also, if at least one UE transmits a NACK, the NW may perform retransmission control of HARQ. In this case, if a different DMRS sequence (or at least one of a cyclic shift and an orthogonal cover code (OCC))) is assigned to each UE, the NW may determine which UE needs to retransmit the PDSCH based on the DMRS sequence (or at least one of a cyclic shift and an orthogonal cover code (OCC)). Also, if the NW cannot determine which UE needs to retransmit the PDSCH, it may retransmit the PDSCH to multiple UEs.

[0146] In this case, even if there is a UE that cannot recognize reception of the multicast PDSCH, more efficient communication can be achieved because the error rate of the DCI (about 1%) is smaller than the error rate of the PDSCH (about 10%).

[0147] As shown in FIG. 7A, when receiving a multicast PDSCH, each UE may transmit a PUCCH (ACK) if the reception process of the PDSCH is successful. In this case, when receiving a multicast PDSCH, each UE may not transmit a PUCCH (NACK) if the reception process of the PDSCH is unsuccessful.

[0148] In this case, if the received power of the ACK transmitted from the multiple UEs is equal to or greater than a threshold (greater than the threshold), the NW may determine that all of the multiple UEs have succeeded in receiving the multicast PDSCH, and may not retransmit the multicast PDSCH. The threshold may be a value that allows estimation that all of the multiple UEs have transmitted an ACK. On the other hand, if the received power of the ACK transmitted from the multiple UEs is less than the threshold (less than the threshold), the NW may determine that there is a UE that has failed in receiving the multicast PDSCH, and may retransmit the multicast PDSCH.

[0149] In this case, reliable communication can be achieved for all of the multiple UEs.

[0150] 9A and 9B are diagrams showing an example of a method for transmitting a HARQ-ACK (PUCCH) corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs. In FIG. 9A, each UE transmits a PUCCH (NACK) when the reception process of the PDSCH fails. In FIG. 9B, each UE does not transmit a PUCCH (ACK) when the reception process of the PDSCH succeeds.

[0151] Note that the numbers of DCI, PDSCH, and PUCCH resources and the time / frequency allocation positions shown in FIG. 9A and FIG. 9B are merely examples, and the present invention is not limited to these examples.

[0152] In addition, the PUCCH transmitted in this embodiment is not limited to sequence-based PUCCH (for example, PUCCH of PF0), and may be PUCCH or PUSCH of other formats (for example, PF1-4, PUCCH with DMRS). Based on the PF applied to the PUCCH, the UE may determine to transmit a NACK and not transmit an ACK as described above for the multicast PDSCH, or may determine to transmit an ACK and not transmit a NACK.

[0153] As described above, according to the fourth embodiment, it becomes possible for a plurality of UEs to appropriately transmit HARQ-ACK using non-orthogonal UL resources, and it is possible to suppress a decrease in the efficiency of uplink resource utilization.

[0154] (Wireless communication system) A configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination of these methods.

[0155] 10 is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE), 5th generation mobile communication system New Radio (5G NR), or the like, which are specified by the Third Generation Partnership Project (3GPP).

[0156] Furthermore, the wireless communication system 1 may support dual connectivity between a plurality of Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), and the like.

[0157] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN) and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN and the LTE (E-UTRA) base station (eNB) is the SN.

[0158] The wireless communication system 1 may support dual connectivity between multiple base stations in the same RAT (for example, dual connectivity in which both the MN and the SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0159] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are arranged in the macrocell C1 and form a small cell C2 that is narrower than the macrocell C1. A user terminal 20 may be located in at least one of the cells. The arrangement and number of each cell and user terminal 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as a base station 10.

[0160] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

[0161] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a frequency band higher than FR2.

[0162] Furthermore, the user terminal 20 may perform communication in each CC using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD).

[0163] The multiple base stations 10 may be connected by wire (e.g., optical fiber conforming to Common Public Radio Interface (CPRI), X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0164] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include at least one of, for example, an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0165] The user terminal 20 may be a terminal compatible with at least one of communication methods such as LTE, LTE-A, and 5G.

[0166] In the wireless communication system 1, a wireless access scheme based on Orthogonal Frequency Division Multiplexing (OFDM) may be used. For example, in at least one of the downlink (DL) and the uplink (UL), Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), etc. may be used.

[0167] The radio access scheme may be called a waveform. In the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0168] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as a downlink channel.

[0169] In addition, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

[0170] The PDSCH transmits user data, higher layer control information, a System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit a Master Information Block (MIB).

[0171] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information of at least one of the PDSCH and the PUSCH.

[0172] In addition, DCI for scheduling PDSCH may be called DL assignment, DL DCI, etc., and DCI for scheduling PUSCH may be called UL grant, UL DCI, etc. In addition, PDSCH may be replaced with DL data, and PUSCH may be replaced with UL data.

[0173] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources to search for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or multiple search spaces. The UE may monitor a CORESET associated with a certain search space based on the search space configuration.

[0174] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be called a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," and "CORESET setting" in the present disclosure may be read as interchangeable terms.

[0175] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery acknowledgement information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and a scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0176] In the present disclosure, a downlink, an uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning of the channels.

[0177] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

[0178] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including the SS (PSS, SSS) and the PBCH (and the DMRS for the PBCH) may be called an SS / PBCH block, an SS Block (SSB), or the like. In addition, the SS, SSB, and the like may also be called a reference signal.

[0179] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may be called a user equipment specific reference signal (UE-specific reference signal).

[0180] (base station) 11 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140 may be provided.

[0181] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and the base station 10 may be assumed to have other functional blocks necessary for wireless communication. Some of the processes of each unit described below may be omitted.

[0182] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured with a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0183] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transmission and reception unit 120, the transmission and reception antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transmission and reception unit 120. The control unit 110 may perform call processing (setting, release, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0184] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0185] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be configured from a transmitting unit and a receiving unit. The transmitting unit may be configured from a transmission processing unit 1211 and an RF unit 122. The receiving unit may be configured from a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0186] The transmitting / receiving antenna 130 can be composed of an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0187] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0188] The transceiver 120 may form at least one of a transmission beam and a reception beam using digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), or the like.

[0189] The transceiver 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0190] The transceiver 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0191] The transceiver unit 120 (RF unit 122) may perform modulation to a radio frequency band, filtering, amplification, and the like on the baseband signal, and transmit the radio frequency band signal via the transceiver antenna .

[0192] On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency signal received by the transceiver antenna .

[0193] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0194] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc., based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0195] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data) for the user terminal 20, control plane data, etc.

[0196] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0197] The transceiver 120 may transmit downlink control information (DCI) for scheduling a multicast downlink shared channel. The controller 110 may control reception of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI (first and second embodiments).

[0198] The transceiver 120 may transmit downlink control information (DCI) for scheduling a multicast downlink shared channel. The controller 110 may control reception of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI. The DCI may be common to a plurality of terminals (first and third embodiments).

[0199] The transceiver 120 may transmit downlink control information (DCI) for scheduling a multicast downlink shared channel. The controller 110 may determine time and frequency resources for receiving a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI. The resources may overlap at least in part with resources used by multiple terminals (first and fourth embodiments).

[0200] (User terminal) 12 is a diagram showing an example of the configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0201] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and the user terminal 20 may be assumed to have other functional blocks necessary for wireless communication. Some of the processes of each unit described below may be omitted.

[0202] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured with a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0203] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission / reception, measurement, etc. using the transmission / reception unit 220 and the transmission / reception antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transmission / reception unit 220.

[0204] The transmitting / receiving unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transmitting / receiving unit 220 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transmitting / receiving circuit, and the like, which are described based on common understanding in the technical field related to the present disclosure.

[0205] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0206] The transmitting / receiving antenna 230 can be composed of an antenna described based on common understanding in the technical field to which this disclosure pertains, such as an array antenna.

[0207] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0208] The transceiver 220 may form at least one of a transmission beam and a reception beam using digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), or the like.

[0209] The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0210] The transceiver 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit sequence to be transmitted, and output a baseband signal.

[0211] Whether or not to apply the DFT process may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver 220 (transmission processor 2211) may perform the DFT process as the transmission process to transmit the channel using a DFT-s-OFDM waveform, and may not perform the DFT process as the transmission process if transform precoding is enabled for the channel.

[0212] The transceiver unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, and the like on the baseband signal, and transmit the radio frequency band signal via the transceiver antenna 230.

[0213] On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency signal received by the transceiver antenna 230.

[0214] The transceiver 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0215] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0216] In addition, the transmitting section and the receiving section of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving section 220 and the transmitting / receiving antenna 230.

[0217] The transceiver 220 may receive downlink control information (DCI) for scheduling a multicast downlink shared channel. The controller 210 may control transmission of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI (first and second embodiments).

[0218] The control unit 210 may determine time and frequency resources for transmitting the HARQ-ACK based on the DCI, which may not overlap with uplink control channel (PUCCH) resources transmitted by another terminal (second embodiment).

[0219] When multicast is set by higher layer signaling and the DCI is scrambled by a specific wireless network temporary identifier, the control unit 210 may control the reception processing of the downlink shared channel by replacing a specific field included in the DCI with a parameter for multicast (second embodiment).

[0220] The specific field may be a modulation and coding scheme field (second embodiment).

[0221] The transceiver 220 may receive downlink control information (DCI) that schedules a multicast downlink shared channel. The controller 210 may control transmission of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) to the downlink shared channel based on the DCI. The DCI may be common to multiple terminals (first and third embodiments).

[0222] The control unit 210 may determine time and frequency resources for transmitting the HARQ-ACK based on the DCI, which may not overlap with uplink control channel (PUCCH) resources transmitted by another terminal (third embodiment).

[0223] When the resource for transmitting the HARQ-ACK is a resource based on the configuration grant, the control unit 210 may determine to transmit the HARQ-ACK (third embodiment).

[0224] When multicast is set by higher layer signaling and the DCI is scrambled by a specific wireless network temporary identifier, the control unit 210 may control the reception processing of the downlink shared channel by replacing a specific field included in the DCI with a parameter for multicast (third embodiment).

[0225] The transceiver 220 may receive downlink control information (DCI) that schedules a multicast downlink shared channel. The controller 210 may determine time and frequency resources for transmitting a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI. The resources may overlap at least a part of resources used by another terminal (first and fourth embodiments).

[0226] The control unit 210 may perform control so that an acknowledgment (ACK) for the downlink shared channel is transmitted using resources that overlap with ACKs from other terminals (fourth embodiment).

[0227] The control unit 210 may perform control so that a negative acknowledgement (NACK) for the downlink shared channel is transmitted using resources that overlap with NACKs from other terminals (fourth embodiment).

[0228] When the reception process of the downlink shared channel is successful, the control unit 210 may perform control so as not to transmit an acknowledgement (ACK) for the downlink shared channel (fourth embodiment).

[0229] (Hardware configuration) The block diagrams 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. The method of realizing each functional block is not particularly limited. That is, each functional block may be realized by using one device that is physically or logically combined, or may be realized by using two or more devices that are physically or logically separated and directly or indirectly connected (for example, by wire, wirelessly, etc.). The functional blocks may be realized by combining the one device or the multiple devices with software.

[0230] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs the function of transmission may be called a transmitting unit, a transmitter, and the like. In either case, as described above, the method of realization is not particularly limited.

[0231] For example, a base station, a user terminal, etc. in an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 13 is a diagram showing an example of a hardware configuration of a base station and a user terminal according to an embodiment. The above-mentioned base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0232] In this disclosure, the terms "apparatus," "circuit," "device," "section," "unit," and the like can be read interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0233] For example, although only one processor 1001 is shown, there may be multiple processors. Also, the processes may be performed by one processor, or the processes may be performed by two or more processors simultaneously, sequentially, or in other manners. Also, the processor 1001 may be implemented by one or more chips.

[0234] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading a specific software (program) onto hardware such as a processor 1001 and a memory 1002, so that the processor 1001 performs calculations, controls communications via a communication device 1004, and controls at least one of reading and writing of data in the memory 1002 and the storage 1003.

[0235] The processor 1001, for example, operates an operating system to control the entire computer. The processor 1001 may be configured with a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transmission / reception unit 120 (220), etc. may be realized by the processor 1001.

[0236] Moreover, the processor 1001 reads out programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to the programs. As the programs, programs that cause a computer to execute at least a part of the operations described in the above-mentioned embodiments are used. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and operated by the processor 1001, and the other functional blocks may be realized in a similar manner.

[0237] The memory 1002 is a computer-readable recording medium, and may be configured by at least one of, for example, a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically EPROM (EEPROM), a Random Access Memory (RAM), and other suitable storage media. The memory 1002 may be called a register, a cache, a main memory (primary storage device), and the like. The memory 1002 can store a program (program code), a software module, and the like that is executable to implement a wireless communication method according to an embodiment of the present disclosure.

[0238] Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disk, a Blu-ray disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0239] The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., in order to realize at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0240] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a Light Emitting Diode (LED) lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0241] In addition, each device such as the processor 1001 and the memory 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.

[0242] Furthermore, the base station 10 and the user 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), a field programmable gate array (FPGA), etc., and some or all of the functional blocks may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0243] (Modification) In addition, the terms explained in this disclosure and the terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be read as mutually interchangeable. A signal may also be a message. A reference signal may also be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applied standard. A component carrier (CC) may also be called a cell, a frequency carrier, a carrier frequency, etc.

[0244] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may 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.

[0245] Here, the numerology may be a communication parameter applied to at least one of the transmission and reception of a signal or channel, and may indicate at least one of, for example, a subcarrier spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a transmission time interval (TTI), a number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transceiver in the frequency domain, and a specific windowing process performed by a transceiver in the time domain.

[0246] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) in the time domain. A slot may also be a time unit based on numerology.

[0247] A slot may include multiple minislots. Each minislot may be composed of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may be composed of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0248] A radio frame, a subframe, a slot, a minislot, and a symbol each represent a time unit for transmitting a signal. A different name may be used for the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be read as interchangeable with each other.

[0249] For example, one subframe may be called a 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 the 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.

[0250] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0251] 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) in which a transport block, a code block, a code word, etc. are actually mapped may be shorter than the TTI.

[0252] In addition, when one slot or one minislot is called TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit of scheduling. Also, the number of slots (minislots) constituting the minimum time unit of scheduling may be controlled.

[0253] A TTI having a time length of 1 ms may be called a normal TTI (TTI in 3GPP Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a minislot, a subslot, a slot, etc.

[0254] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0255] 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, and may be, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0256] In addition, an RB may include one or more symbols in the time domain, and may have a length of one slot, one minislot, one subframe, or one TTI. Each of one TTI, one subframe, etc. may be composed of one or more resource blocks.

[0257] In addition, one or more RBs may be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0258] 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.

[0259] 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 numerology on a carrier, where the common RBs may be identified by the index of the RBs relative to a common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0260] The BWP may include a UL BWP (a BWP for UL) and a DL BWP (a BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0261] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell", "carrier", etc. in this disclosure may be replaced with "BWP".

[0262] The above-mentioned structures of radio frames, subframes, slots, minislots, and symbols are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

[0263] In addition, the information, parameters, etc. described in the present disclosure may be represented using absolute values, may be represented using relative values ​​from a predetermined value, or may be represented using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0264] The names used for parameters and the like in this disclosure are not limiting in any way. Furthermore, the formulas and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (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 limiting in any way.

[0265] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, the 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.

[0266] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via a plurality of network nodes.

[0267] Input and output information, signals, etc. may be stored in a specific location (e.g., memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added to. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0268] 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 in the present disclosure 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, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0269] The physical layer signaling may be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. The RRC signaling may be called an RRC message, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc. The MAC signaling may be notified, for example, by using a MAC Control Element (CE).

[0270] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0271] The determination may be made based on a value represented by a single bit (0 or 1), a Boolean value represented as true or false, or by comparing numerical values ​​(e.g., with a predetermined value).

[0272] 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.

[0273] Additionally, software, instructions, information, etc. may be transmitted or received over a transmission medium. For example, if the 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, etc.), then these wired and / or wireless technologies are included within the definition of transmission media.

[0274] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0275] In this disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," and the like may be used interchangeably.

[0276] In this disclosure, terms such as "Base Station (BS)", "radio base station", "fixed station", "NodeB", "eNB (eNodeB)", "gNB (gNodeB)", "access point", "Transmission Point (TP)", "Reception Point (RP)", "Transmission / Reception Point (TRP)", "panel", "cell", "sector", "cell group", "carrier", "component carrier", etc. may be used interchangeably. A base station may also be referred to by terms such as a macro cell, a small cell, a femto cell, a pico cell, etc.

[0277] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire 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 small base station for indoor use (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or a base station subsystem that provides communication services in this coverage.

[0278] In this disclosure, the terms "Mobile Station (MS)", "user terminal", "User Equipment (UE)", "terminal", etc. may be used interchangeably.

[0279] A mobile station may also be referred to 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.

[0280] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. At least one of the base station and the mobile station may be a device mounted on a moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving 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 include a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0281] Furthermore, the base station in the present disclosure may be read as a user terminal. For example, each aspect / embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between a plurality of user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user 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, an uplink channel, a downlink channel, etc. may be read as a side channel.

[0282] Similarly, the user terminal in the present disclosure may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0283] In the present disclosure, an operation performed by a base station may be performed by its upper node in some cases. It is clear that in a network including one or more network nodes having base stations, various operations performed for communication with terminals may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME) and a Serving-Gateway (S-GW)), or a combination thereof.

[0284] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched according to implementation. In addition, the processing procedures, sequences, flow charts, etc. of each aspect / embodiment described in this disclosure may be reordered unless inconsistent. 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.

[0285] Each aspect / embodiment described in the present disclosure may be implemented using any of a wide variety of standards, including Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE The present invention may be applied to systems using 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), other appropriate wireless communication methods, next-generation systems that are based on these, etc. Also, the present invention may be applied to a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0286] 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."

[0287] Any reference to an element using a designation such as "first," "second," etc., used in this disclosure 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 precede the second element in some way.

[0288] The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, and the like.

[0289] A "determining" may also be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in a memory), etc.

[0290] Also, "determination" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. That is, "determination" may be considered to be "deciding" to perform some action.

[0291] Additionally, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," etc.

[0292] As used in this disclosure, 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 the elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0293] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, and the like, as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, and the like, as some non-limiting and non-exhaustive examples.

[0294] 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."

[0295] 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." Further, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0296] In this disclosure, where articles have been 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.

[0297] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented as modified and altered forms without departing from the spirit and scope of the invention defined based on the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the invention according to the present disclosure.

Claims

1. a receiver for receiving a configuration of a Physical Uplink Control Channel (PUCCH) resource corresponding to a multicast Physical Downlink Shared Channel (PDSCH), a Downlink Control Information (DCI) for scheduling the PDSCH, and the PDSCH, the configuration being transmitted using Radio Resource Control (RRC) signaling; a control unit that determines a PUCCH resource for a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the PDSCH based on the setting, a PUCCH resource indicator field included in the DCI, and a control channel element (CCE) index of a physical downlink control channel (PDCCH) that transmits the DCI, The DCI is common to a plurality of terminals, A terminal, wherein the PUCCH format for the PUCCH resource is a PUCCH format without a demodulation reference signal.

2. The terminal of claim 1 , wherein the receiver monitors the DCI in a common search space for multicast.

3. The terminal according to claim 1 , wherein a CRC (Cyclic Redundancy Check) of the DCI is scrambled by a group-common Radio Network Temporary Identifier (RNTI).

4. receiving a configuration of Physical Uplink Control Channel (PUCCH) resources corresponding to a multicast Physical Downlink Shared Channel (PDSCH), downlink control information (DCI) scheduling the PDSCH, and the PDSCH, the configuration being transmitted using Radio Resource Control (RRC) signaling; determining a PUCCH resource for a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the PDSCH based on the configuration, a PUCCH resource indicator field included in the DCI, and a control channel element (CCE) index of a physical downlink control channel (PDCCH) carrying the DCI; The DCI is common to a plurality of terminals, A wireless communication method for a terminal, wherein a PUCCH format for the PUCCH resource is a PUCCH format without a demodulation reference signal.

5. A transmitter for transmitting a configuration of a Physical Uplink Control Channel (PUCCH) resource corresponding to a multicast Physical Downlink Shared Channel (PDSCH), downlink control information (DCI) for scheduling the PDSCH, and the PDSCH, the configuration being transmitted using Radio Resource Control (RRC) signaling; a control unit that indicates a PUCCH resource of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the PDSCH using the setting, a PUCCH resource indicator field included in the DCI, and a control channel element (CCE) index of a physical downlink control channel (PDCCH) that transmits the DCI, The DCI is common to a plurality of terminals, A base station, wherein the PUCCH format for the PUCCH resource is a PUCCH format without a demodulation reference signal.

6. A system having a base station and a terminal, The base station, A transmitter for transmitting a configuration of a Physical Uplink Control Channel (PUCCH) resource corresponding to a multicast Physical Downlink Shared Channel (PDSCH), downlink control information (DCI) for scheduling the PDSCH, and the PDSCH, the configuration being transmitted using Radio Resource Control (RRC) signaling; a control unit that indicates a PUCCH resource of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the PDSCH using the setting, a PUCCH resource indicator field included in the DCI, and a control channel element (CCE) index of a physical downlink control channel (PDCCH) that transmits the DCI, The terminal includes: A receiving unit that receives the configuration, the DCI, and the PDSCH; a control unit for determining the PUCCH resource based on the configuration, the PUCCH resource indicator field, and the CCE index; The DCI is common to a plurality of terminals, The PUCCH format for the PUCCH resource is a PUCCH format without a demodulation reference signal.

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