Terminal, wireless communication method and base station

Abstract

A terminal according to one embodiment of the present disclosure includes: a receiving unit for receiving downlink control information (DCI) of a downlink shared channel for scheduling multicast; and a control unit for controlling the transmission of a hybrid automatic repeat request acknowledgment (HARQ-ACK) for the downlink shared channel based on the DCI, wherein the DCI is common to multiple terminals. According to one embodiment of the present disclosure, a PDSCH utilizing multicast can be appropriately received.

Description

Technical Field

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

[0002] In the Universal Mobile Telecommunications System (UMTS) network, Long Term Evolution (LTE) is standardized for the purpose of further high-speed data rate, low latency, etc. (Non-Patent Document 1). In addition, LTE-Advanced (3GPP Rel. 10-14) is standardized for the purpose of further increasing the capacity and sophistication of LTE (Release (Rel.) 8, 9 of the Third Generation Partnership Project (3GPP)).

[0003] Successor systems of LTE (for example, also known as the fifth generation mobile communication system (5G), 5G+(plus), the sixth generation mobile communication system (6G), New Radio (NR), 3GPP Rel.15 and later, etc.) are also being studied.

[0004] Prior art literature

[0005] Non-patent literature

[0006] 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

[0007] Problems to be solved by the invention

[0008] In future wireless communication systems (e.g., NR), it is envisioned that multiple user terminals (user equipment (UE)) communicate in an ultra-high density and high traffic environment.

[0009] In NR, it is assumed that in such an environment, multiple UEs receive the same PDSCH while using multicast.

[0010] However, in the NR specifications to date, the method for receiving downlink control information (DCI) of the PDSCH using multicast for UE scheduling and the method for sending HARQ-ACK corresponding to the PDSCH using multicast have not been fully studied. If this method cannot be properly controlled, there is a concern that system performance will be reduced, such as a reduction in throughput.

[0011] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, and a base station that appropriately receive a PDSCH using multicast.

[0012] Means for solving problems

[0013] A terminal involved in one embodiment of the present invention comprises: a receiving unit, which receives downlink control information (DCI) of a downlink shared channel for scheduling multicast; and a control unit, which controls the sending of a hybrid automatic repeat request acknowledgment (Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK)) for the downlink shared channel based on the DCI, and the DCI is common to multiple terminals.

[0014] Effects of the Invention

[0015] According to one aspect of the present disclosure, it is possible to appropriately receive a PDSCH utilizing multicast. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a diagram showing an example of a multicast PDSCH reception process.

[0017] Figure 2A as well as Figure 2B This is a diagram showing an example of an MCS index table used for PDSCH.

[0018] Figure 3 This is a diagram showing an example of a multicast PDSCH reception process.

[0019] Figure 4 This is a diagram showing an example of the correspondence between the TDRA value of the PUSCH resource and the bit of the DCI.

[0020] Figure 5 This is a diagram showing an example of a multicast PDSCH reception process.

[0021] Figure 6 This is a diagram showing an example of a method of transmitting HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs.

[0022] Fig. 7A as well as Figure 7B This is a diagram showing an example of HARQ-ACK detection transmitted from a plurality of UEs in the NW.

[0023] Figure 8A-8C This is a diagram showing an example of a method of transmitting HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs and an example of detecting HARQ-ACK transmitted from a plurality of UEs in a NW.

[0024] Fig. 9A as well as Fig. 9B This is a diagram showing an example of a method of transmitting HARQ-ACK (PUCCH) corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs.

[0025] Fig.10 This is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment.

[0026] Fig.11 This is a diagram showing an example of the structure of a base station involved in one embodiment.

[0027] Fig.12 This is a diagram showing an example of a configuration of a user terminal according to an embodiment.

[0028] Fig.13 This is a diagram showing an example of the hardware configuration of a base station and a user terminal involved in one embodiment. DETAILED DESCRIPTION

[0029] (PUCCH format)

[0030] In future wireless communication systems (e.g., Rel.15 and later, 5G, NR, etc.), the structure (also called format, PUCCH format (PF), etc.) for the uplink control channel (e.g., PUCCH) used in the transmission of uplink control information (UCI) is being studied. For example, in Rel.15NR, support for five types of PF0 to 4 is being studied. In addition, the names of the PFs shown below are only examples, and different names may be used.

[0031] For example, PF0 and 1 are PFs used in the transmission of UCI of up to 2 bits. For example, UCI may also be at least one of delivery confirmation information (also called Hybrid Automatic RepeatreQuest-Acknowledgement (HARQ-ACK)), confirmation (ACK) or negative confirmation (NACK), etc.) and scheduling request (SR). PF0 can be allocated to 1 or 2 code elements, so it is also called short PUCCH or sequence-based short PUCCH, etc. On the other hand, PF1 can be allocated to 4-14 code elements, so it is also called long PUCCH, etc. PF0 can also use a cyclic shift (CS) corresponding to the value of UCI to send a sequence obtained by cyclic shift of the base sequence. In PF1, multiple user terminals may be code division multiplexed (CDM) in the same physical resource block (PRB) by using time domain block spreading using at least one of CS and time domain (TD)-orthogonal cover code (OCC).

[0032] PF2-4 is a PF used in the transmission of UCI of more than 2 bits (for example, channel state information (CSI)), or at least one of CSI, HARQ-ACK and SR). PF2 can be allocated to 1 or 2 codewords, so it is also called short PUCCH, etc. On the other hand, PF3 and 4 can be allocated to 4-14 codewords, so they are also called long PUCCH, etc. In PF4, block spreading before DFT (frequency domain (FD)-OCC) can also be used, and multiple user terminals are CDMed.

[0033] For PF1, PF3, and PF4, intra-slot frequency hopping can also be applied. If the length of PUCCH is set to N symb , then the length before frequency hopping (first hop) can also be floor(N symb / 2), the length after frequency hopping (second hop) can also be ceil(N symb / 2).

[0034] The waveforms of PF0, PF1, and PF2 may also be cyclic prefix (CP)-orthogonal frequency division multiplexing (OFDM). The waveforms of PF3 and PF4 may also be discrete Fourier transform (DFT)-spread(s)-OFDM.

[0035] The allocation of resources (e.g., PUCCH resources) used in the transmission of the uplink control channel is performed using high-layer signaling and / or downlink control information (DCI). Here, the high-layer signaling can be, for example, RRC (Radio Resource Control) signaling, system information (e.g., at least one of the remaining minimum system information (RMSI: Remaining Minimum System Information), other system information (OSI: Other System Information), master information block (MIB: Master Information Block), system information block (SIB: System Information Block)), and broadcast information (physical broadcast channel (PBCH: Physical Broadcast Channel)).

[0036] In addition, in NR, the number of symbols allocated to PUCCH (also referred to as PUCCH allocation symbols, PUCCH symbols, etc.) can be determined by time slot specificity, cell specificity, user terminal specificity, or a combination thereof. Since it is expected that the more the number of PUCCH symbols is increased, the longer the communication distance (coverage range) is, the more the number of symbols is increased, so it is envisaged that the user terminal is farther away from the base station (e.g., eNB, gNB), and the more the number of symbols is increased.

[0037] (NR multicast / broadcast)

[0038] 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 the NW to the UE is based on unicast transmission. In this case, it is assumed that each UE uses multiple reception opportunities (reception opportunities) corresponding to multiple beams (or panels) of the NW to receive the same downlink (DL) data signal / channel (for example, a downlink shared channel (PDSCH)) transmitted from the NW to multiple UEs.

[0039] In addition, it is assumed that in an ultra-high density and high traffic environment such as a stadium where multiple UEs are geographically dense, multiple UEs simultaneously receive the same signal / channel. In this case, multiple UEs exist in the same area and each UE receives the same signal / channel. Therefore, it can be considered that although the reception of the signal / channel by each UE through unicast can ensure the reliability of communication, it reduces the efficiency of resource utilization.

[0040] On the other hand, there are also use cases where the same DL data signal / channel is multicast (broadcast) to multiple UEs (e.g., TVs, radios, etc.) However, in this use case, the NW does not confirm the reception of the DL data signal / channel of each UE, so it is difficult to ensure reliability.

[0041] Therefore, the inventors of the present invention have come up with a method for receiving downlink control information (DCI) of a PDSCH that utilizes multicast scheduling of UE, and a method for sending delivery confirmation information (for example, also referred to as Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK)), ACK / NACK, etc.) corresponding to the PDSCH that utilizes multicast.

[0042] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The wireless communication methods according to the embodiments may be applied individually or in combination.

[0043] (Wireless Communication Method)

[0044] Multicast / broadcast may be configured from the NW to a plurality of UEs. The multicast / broadcast configuration may be performed using higher layer signaling.

[0045] A UE configured for multicast / broadcast may also receive a PDSCH scheduled by blindly detecting (receiving) a DCI (PDCCH) in at least one of the downlink control channel (PDCCH) monitoring opportunities, search spaces, and control resource sets (CORESET) corresponding to the multicast / broadcast. This PDSCH may also be referred to as a PDSCH utilizing multicast.

[0046] Furthermore, a UE for which multicast / broadcast is configured may use the PUCCH or the PUSCH to transmit HARQ-ACK / NACK for the PDSCH utilizing multicast.

[0047] The HARQ-ACK / NACK may be transmitted as 1 bit for each transport block (TB) / codeword (CW) of the PDSCH using multicast, or as 1 bit for each of a plurality of TBs / CWs.

[0048] In addition, in the present disclosure, the high-layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

[0049] MAC signaling may also use, for example, MAC Control Element (MAC CE), MAC Protocol Data Unit (MAC Protocol Data Unit (PDU)), etc. Broadcast information may also be, for example, Master Information Block (MIB), System Information Block (SIB), minimum system information (Remaining Minimum System Information (RMSI)), Other System Information (Other System Information (OSI)), etc.

[0050] The physical layer signaling may be, for example, downlink control information (Downlink Control Information (DCI))).

[0051] In the present disclosure, multicast may be replaced with broadcast (broadcast information). In addition, PDSCH using multicast may be replaced with PDSCH common to multiple UEs, common PDSCH, shared PDSCH, multicast PDSCH, broadcast (notification) PDSCH, etc.

[0052] In the present disclosure, A / B may also mean at least one of A and B.

[0053] In the present disclosure, PUCCH / PUSCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH may be simply referred to as resources for HARQ-ACK transmission.

[0054] In the present disclosure, each of the multiple UEs may also be referred to as a UE, or simply referred to as a UE.

[0055] <First embodiment>

[0056] With respect to multiple HARQ-ACK transmission resources allocated to multiple UEs corresponding to a downlink shared channel (PDSCH) utilizing multicast, each UE may also use mutually orthogonal (non-overlapping) UL resources (orthogonal UL resources) to transmit HARQ-ACK. In other words, each UE may also be allocated UE-specific (UE-specific or dedicated) HARQ-ACK transmission PUCCH / PUSCH resources. This situation is described in detail in the following second and third embodiments.

[0057] In addition, with respect to multiple HARQ-ACK transmission resources allocated to multiple UEs corresponding to a downlink shared channel (PDSCH) utilizing multicast, each UE may also use mutually non-orthogonal (at least partially overlapping) UL resources (non-orthogonal UL resources) to transmit HARQ-ACK. In other words, each UE may not be allocated a UE-specific PUCCH / PUSCH resource for HARQ-ACK transmission, but may be allocated (common) PUCCH / PUSCH resources for HARQ-ACK transmission that overlap between multiple UEs. This situation is described in detail in the following third and fourth embodiments.

[0058] <Second embodiment>

[0059] In the second embodiment, a situation where multiple UEs use orthogonal UL resources to send HARQ-ACK is described. Specifically, the following situation is described: each UE receives a UE-specific DCI, each DCI is scheduled on a PDSCH (multicast PDSCH) common to multiple UEs, and indicates a PUCCH / PUSCH resource for UE-specific HARQ-ACK transmission corresponding to the multicast PDSCH.

[0060] Figure 1 FIG. 1 is a diagram showing an example of a multicast PDSCH reception process. Figure 1 In the present invention, a UE monitors UE-specific DCI (at least DCI1 among DCI0-3) and receives a multicast PDSCH, and uses UE-specific PUCCH resources (at least PUCCH1 among PUCCH0-3) to send a HARQ-ACK corresponding to the multicast PDSCH.

[0061] in addition, Figure 1 The number of DCI, PDSCH, and PUCCH resources and their time / frequency allocation positions shown are merely examples, and the present invention is not limited to these examples.

[0062] Search Space

[0063] The search space used to monitor UE-specific DCI may be a common search space or a UE-specific search space. In addition, the search space used to monitor UE-specific DCI may also be a search space (or a control resource set (CORESET)) dedicated to multicast / broadcast scheduling specified by the specification.

[0064] RNTI

[0065] The UE-specific DCI may be scrambled by a cyclic redundancy check (CRC) using a UE-specific Radio Network Temporary Identifier (RNTI) (e.g., a cell (C-) RNTI) or by a CRC scrambled using a UE-common RNTI. In addition, the UE-specific DCI may also be scrambled by a CRC scrambled using a RNTI dedicated to multicast / broadcast scheduling as specified by the specification.

[0066] 《PUCCH / PUSCH Resources》

[0067] The PUCCH resources for HARQ-ACK transmission may also be indicated by at least one of a PUCCH Resource Indicator (PRI) included in the DCI (scheduling DCI) for scheduling multicast PDSCH and a control channel element (CCE) index (e.g., the initial CCE index) of the PDCCH carrying the DCI. In addition, the PUCCH resources for HARQ-ACK transmission may also be configured for each UE through higher layer signaling (e.g., RRC signaling) with N (N is an integer, e.g., 16) PUCCH resources, and specified from the N PUCCH resources by at least one of the PRI included in the scheduling DCI and the CCE index of the PDCCH of the DCI.

[0068] PUSCH resources for HARQ-ACK transmission can also be used through higher-layer signaling (for example, RRC signaling), M (M is an integer) time / frequency resources are set for each UE and specified by at least one of the time domain resource allocation (Time Domain Resource Assignment (TDRA)) field and the frequency domain resource allocation (Frequency Domain Resource Assignment (FDRA)) field included in the DCI.

[0069] DCI Format

[0070] The multicast PDSCH may be scheduled using DCI format 1_1 / 1_0 or a DCI format dedicated to the multicast PDSCH.

[0071] When multicast PDSCH is scheduled using DCI format 1_1 / 1_0, the existing DCI format can be used, so UE implementation is easy. In addition, when multicast PDSCH is scheduled using DCI format 1_0 with fewer UE-specific fields, multicast PDSCH, which is a UE-common PDSCH, can be efficiently scheduled.

[0072] In the case where a multicast PDSCH is scheduled using a DCI format dedicated to the multicast PDSCH, the UE may also report UE capability information (UE Capability) related to whether the DCI format dedicated to the multicast PDSCH can be supported to the network (NW, for example, gNB). In this case, the combination of DCI sizes (payload size, number of bits) increases, the number of blind detections of DCI implemented by the UE increases, and the complexity of UE operation increases, so that only UEs that support the DCI format may monitor the DCI format.

[0073] In addition, when a multicast PDSCH is scheduled by DCI format 1_0, and reception of the multicast PDSCH is set by higher layer signaling, and the DCI is scrambled by CRC by RNTI dedicated to multicast / broadcast scheduling, the UE may control the reception process of the multicast PDSCH by replacing the field value included in the DCI format 1_0 with a parameter for multicast without changing the size of the DCI format 1_0. In this case, the UE may also use the DCI format 1_0 that is not scrambled by CRC by RNTI dedicated to multicast / broadcast scheduling for purposes other than scheduling of the multicast PDSCH.

[0074] In addition, when multicast PDSCH is scheduled through DCI format 1_0 and the reception of multicast PDSCH is set through high-level signaling, the UE can also control the reception processing of multicast PDSCH by replacing the fields contained in the DCI format 1_0 with parameters for multicast without changing the size of DCI format 1_0.

[0075] In the case where multicast PDSCH is scheduled through DCI format 1_0, the UE may also use at least one of the fields contained in DCI format 1_0, including the DCI format identifier field, the frequency domain resource allocation field, the time domain resource allocation field, the mapping field from virtual resource block (VRB) to physical resource block (PRB), the new data indicator (NDI) field, the redundancy version (RV) field, the HARQ process number field, the downlink allocation index (DAI) field, the transmit power control (Transmission Power Control (TPC)) command field for the scheduled PUCCH, the PRI field, and the timing indicator (PDSCH-to-HARQ_feedback timing indicator, HARQ feedback timing indicator) field in the scheduling of the multicast PDSCH.

[0076] In addition, when the multicast PDSCH is scheduled through DCI format 1_0, the UE may not use the modulation and coding scheme (MCS) field in the scheduling of the multicast PDSCH among the fields included in the DCI format 1_0. In this case, the MCS parameter or MCS index of the multicast PDSCH may also be a certain value.

[0077] The certain value may also be specified by the specification. For example, the certain value may also be the minimum (or the Xth smallest) MCS index of the MCS index table for PDSCH that is pre-specified by the specification. In addition, the certain value may also be notified to the UE through high-layer signaling. In addition, the certain value may also be a value reported to the NW through UE capability information (UE Capability).

[0078] In addition, if the reliability of multicast is considered, it is assumed that 256 (quadrature amplitude modulation (QAM)) is not used for multicast PDSCH. In this case, the table of parameters for 256QAM is not included (MCS index table 1 for PDSCH ( Figure 2A )) and a table containing parameters for 256QAM (MCS index table 2 for PDSCH ( Figure 2B )) can also be specified by the specification.

[0079] In this case, the UE may also use MCS index table 1 for the MCS index of the multicast PDSCH, and determine at least one of the modulation order, target code rate, and spectral efficiency from the MCS index. Specifically, in the scheduling of the multicast PDSCH, when the high-level parameters (MCS-Table-PDSCH, mcs-Table) are not set in the MCS index table 2 (256QAM table, 'qam256'), and when the DCI scrambled by CRC is received through the C-RNTI, the UE may also refer to the MCS index table 1.

[0080] in addition, Figure 2A as well as Figure 2B The values ​​of the MCS index table for PDSCH shown are only examples and are not limited thereto. In addition, the MCS index table may be replaced with a table that does not include modulation orders greater than a specific value (eg, 8).

[0081] The UE may not use the MCS field in the fields included in DCI format 1_0 in the scheduling of multicast PDSCH in a manner independent of whether the DCI format dedicated to multicast PDSCH scheduling is specified, whether the RNTI dedicated to multicast PDSCH scheduling is specified, and whether the fields included in DCI format 1_0 are replaced. In this case, the UE can distinguish between DCI for scheduling multicast PDSCH and DCI for scheduling other PDSCHs based on the presence or absence of the MCS field, and can effectively use the unused fields in the DCI for scheduling multicast PDSCH for other purposes (for example, increase in the bit field of the TDRA / FDRA field).

[0082] <Third embodiment>

[0083] In the third embodiment, a situation where multiple UEs use orthogonal UL resources to send HARQ-ACK is described. Specifically, the following situation is described: each UE receives a DCI common to multiple UEs, and the DCI schedules a PDSCH (multicast PDSCH) common to multiple UEs, and indicates a PUCCH / PUSCH resource for UE-specific HARQ-ACK transmission corresponding to the multicast PDSCH. In addition, in this embodiment, the above-mentioned second embodiment can also be applied to a part of the multiple UEs.

[0084] Figure 3 FIG. 1 is a diagram showing an example of a multicast PDSCH reception process. Figure 3In the present invention, a UE monitors the UE-common DCI (DCI1) and receives the multicast PDSCH, and uses the UE-specific PUCCH resources (at least PUCCH1 among PUCCH0-3) to send the HARQ-ACK corresponding to the multicast PDSCH.

[0085] In addition, if Figure 3 The number of DCI, PDSCH, and PUCCH resources and their time / frequency allocation positions shown are merely examples, and the present invention is not limited to these examples.

[0086] Search Space

[0087] The search space used to monitor UE-common DCI may be a common search space or a UE-specific search space. In addition, the search space used to monitor UE-common DCI may also be a search space (or a control resource set (CORESET)) dedicated to multicast / broadcast scheduling specified by the specification.

[0088] RNTI

[0089] The UE-common DCI can be CRC-scrambled by either a UE-specific Radio Network Temporary Identifier (RNTI) (e.g., cell (C-) RNTI) or a UE-common RNTI. The UE-common RNTI can also be a newly defined RNTI. In addition, the UE-specific DCI can also be CRC-scrambled by a RNTI defined by the specification for multicast / broadcast scheduling.

[0090] 《PUSCH / PUCCH Resources》

[0091] PUSCH resources for HARQ-ACK transmission can also be used through higher-layer signaling (e.g., RRC signaling), and M (M is an integer) time / frequency resources are set for each UE and specified by at least one of the TDRA field and the FDRA field included in the DCI.

[0092] The PUCCH resources for HARQ-ACK transmission may also be indicated by at least one of the PRI included in the DCI (scheduling DCI) for scheduling the multicast PDSCH and the CCE index (e.g., the initial CCE index) of the PDCCH carrying the DCI. In addition, the PUCCH resources for HARQ-ACK transmission may also be set for each UE through higher layer signaling (e.g., RRC signaling), and N (N is an integer, e.g., 16) PUCCH resources are specified from the N PUCCH resources through at least one of the PRI included in the scheduling DCI and the CCE index of the PDCCH carrying the DCI.

[0093] However, when the UE performs the above-mentioned method for determining PUSCH / PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, there is a concern that the PUSCH / PUCCH resources of multiple UEs may overlap. A method for avoiding the overlap of the PUSCH / PUCCH resources of multiple UEs is described below.

[0094] The UE may also use the PUSCH based on the configured grant to send the HARQ-ACK corresponding to the multicast PDSCH. In the present disclosure, the PUSCH based on the configured grant may also be replaced by the PUSCH based on the configured grant (configured grant based PUSCH), the configured grant PUSCH, the PUSCH using the configured grant, etc. In this case, the UE may also be configured with the configured grant and use the PUSCH resources configured by the configured grant to send the HARQ-ACK corresponding to the multicast PDSCH. In addition, in the case where the reception of the multicast PDSCH is configured, the UE may also be assumed to be configured with the configured grant (and, PUSCH resources).

[0095] At this time, regarding the HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also use the value of the HARQ-ACK timing indicator field (HARQ-ACK timing indicator (PDSCH-to-HARQ_feedbacktiming indicator) field) included in DCI format 1_0. In the time domain (e.g., time slot) represented by the HARQ-ACK timing indicator field (HARQ-ACK timingindicator field), the UE may also transmit the HARQ-ACK corresponding to the multicast PDSCH when the PUSCH resources based on the setting permission are set.

[0096] Furthermore, in the time domain indicated by the HARQ-ACK timing indicator field, when PUSCH resources based on the setting permission are not set, the UE may not send the HARQ-ACK corresponding to the multicast PDSCH.

[0097] In addition, in the time domain represented by the HARQ-ACK timing indicator field, when the PUSCH resources based on the set permission are not set, the UE can also maintain (store) the HARQ-ACK bits corresponding to the multicast PDSCH, and send the HARQ-ACK corresponding to the multicast PDSCH in the PUSCH resources based on the set permission in the next transmission opportunity (timing).

[0098] In addition, in the time domain represented by the HARQ-ACK timing indicator field, if the PUSCH resources based on the setting permission are not set, the UE may also discard the HARQ-ACK bits corresponding to the multicast PDSCH. The UE may also generate and send the HARQ-ACK corresponding to the new multicast PDSCH in the PUSCH resources based on the setting permission in the next transmission opportunity (timing).

[0099] In addition, the UE may also be configured with PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH. The PUCCH resources may also be configured with PUCCH resources for HARQ-ACK transmission corresponding to the unicast PDSCH (PUCCH format, starting symbol, duration (duration, number of symbols), physical resource block (PRB) index (the initial PRB index, for example, at least one of the starting PRB index and the second hopping PRB index), at least one of the initial cyclic shift (CS) index). The PUCCH resources may also be configured in the UE through high-layer signaling.

[0100] In addition, the UE may also be configured / activated with periodic or semi-continuous PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH (also referred to as configured PUCCH resources). In other words, when the multicast PDSCH is configured, the UE may also assume that the PUCCH resources for HARQ-ACK transmission are configured PUCCH resources. The UE may also be configured with configured PUCCH resources through higher layer signaling. The configuration of configuring the PUCCH resources may also include parameters indicating the period of the PUCCH.

[0101] The UE may also use the configured PUCCH resources to send the HARQ-ACK corresponding to the multicast PDSCH.

[0102] At this time, regarding the HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also use the value of the HARQ-ACK timing indicator field included in the DCI format 1_0. In the time domain (e.g., time slot) indicated by the HARQ-ACK timing indicator field, when the configured PUCCH resource for the HARQ-ACK transmission corresponding to the multicast PDSCH is configured, the UE may also transmit the HARQ-ACK corresponding to the multicast PDSCH.

[0103] In addition, in the time domain represented by the HARQ-ACK timing indicator field, when the configured PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH are not configured, the UE may not transmit the HARQ-ACK corresponding to the multicast PDSCH.

[0104] In addition, in the time domain represented by the HARQ-ACK timing indicator field, when the PUCCH resources configured for sending HARQ-ACK corresponding to the multicast PDSCH are not configured, the UE may maintain (store) the HARQ-ACK bits corresponding to the multicast PDSCH and send the HARQ-ACK corresponding to the multicast PDSCH in the PUCCH resources configured for sending HARQ-ACK corresponding to the multicast PDSCH in the next sending opportunity (timing).

[0105] In addition, in the time domain represented by the HARQ-ACK timing indicator field, when the configured PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH are not configured, the UE may also discard the HARQ-ACK bits corresponding to the multicast PDSCH. The UE may also generate and transmit the HARQ-ACK corresponding to the new multicast PDSCH in the configured PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH in the next transmission opportunity (timing).

[0106] In addition, in the present disclosure, PUSCH resources based on setting permission, PUCCH resources based on setting permission, resources based on setting permission, etc. can also be replaced with each other.

[0107] The PUSCH / PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH may be indicated by a DCI having a CRC scrambled by at least one of a UE index (ID) and an RNTI.

[0108] In this case, the RNTI used in the PUSCH / PUCCH resource determination for HARQ-ACK transmission corresponding to the multicast PDSCH may also be a UE-specific RNTI (e.g., C-RNTI). In other words, the RNTI used in the PUSCH / PUCCH resource determination for HARQ-ACK transmission corresponding to the multicast PDSCH may also be different from the UE-common RNTI used in the CRC scrambling of the DCI that schedules the multicast PDSCH.

[0109] Furthermore, the PUSCH / PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH may be indicated by at least one of the first method and the second method described below.

[0110] [First method]

[0111] Regarding the PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also transform at least one of the time resources, frequency resources, symbols, CS, and sequences of the PUCCH resources determined by the PRI / CCE index through a certain transformation formula. In addition, regarding the PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also assume that at least one of the time resources, frequency resources, symbols, CS, and sequences of the PUCCH resources determined by the PRI / CCE index is transformed through a certain transformation formula.

[0112] The transformation formula may also be determined based on a UE-specific RNTI (e.g., C-RNTI). For example, the transformation formula may also be given by mod({value of UE-specific RNTI}, M) (M is an arbitrary integer). In addition, mod(X, Y) means the remainder of dividing X by Y (modulo operation).

[0113] The value M used in the transformation equation may be pre-defined by the specification or determined by higher layer signaling. The value of M can be used to control the utilization efficiency of PUCCH resources and the possibility of PUCCH resource collision between UEs.

[0114] [Second method]

[0115] In addition, regarding the PUCCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also assume that the maximum number of PUCCH resources 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.

[0116] The method of indicating the PUCCH resources for the UE is, for example, 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 resources by a 3-bit PRI. At this time, when 16 PUCCH resources are set for the 2nd PUCCH resource set, a value derived from mod({UE-specific RNTI value}, M) and PRI may be used to determine one PUCCH resource from the 16 PUCCH resources. The value M may also be the maximum number of PUCCH resources included in the PUCCH resource set divided by the maximum number of PUCCH resources included in the PUCCH resource set up to Rel.16.

[0117] In addition, regarding the PUSCH resources for HARQ-ACK transmission corresponding to the multicast PDSCH, the UE may also determine (be instructed to) the TDRA / FDRA for the PUSCH resources based on a certain transformation formula from the setting values ​​of TDRA / FDRA for multiple PUSCH resources set by higher layer signaling (e.g., TDRA / FDRA table). The transformation formula may also be mod({UE-specific RNTI value}, M) (M is an arbitrary integer).

[0118] Figure 4 This is a diagram showing an example of the correspondence between the TDRA value of the PUSCH resource and the bit of the DCI. Figure 4An example of the relationship between the TDRA value of the PUSCH resource and the DCI bit is shown, but the correspondence (table) showing the relationship between the FDRA value of the PUSCH resource and the DCI bit can also be set as a setting value, and the correspondence (table) showing the relationship between the TDRA value and the FDRA value of the PUSCH resource and the DCI bit can also be set as a setting value.

[0119] UE can also use Figure 4 The TDRA of the PUSCH resource for HARQ-ACK transmission corresponding to the multicast PDSCH is determined by the correspondence relationship (table) shown. The UE may be configured with multiple TDRA tables through higher layer signaling, and the TDRA table of the PUSCH resource to be used may be determined from mod({UE-specific RNTI value}, M). Figure 4 Although the case of M=2 is shown, M and the values ​​described in the table are merely examples and are not limited thereto.

[0120] In addition, when the value of the UE-specific RNTI is expressed in binary, the UE may convert the value of the UE-specific RNTI into decimal and perform the above-mentioned modular operation.

[0121] DCI Format

[0122] The DCI common to multiple UEs that schedule the multicast PDSCH may be either a DCI format 1_1 / 1_0 or a DCI format dedicated to the multicast PDSCH.

[0123] When multicast PDSCH is scheduled using DCI format 1_1 / 1_0, the existing DCI format can be used, so UE implementation is easy. In addition, when multicast PDSCH is scheduled using DCI format 1_0 with fewer UE-specific fields, multicast PDSCH, which is a UE-common PDSCH, can be efficiently scheduled.

[0124] In the case where a multicast PDSCH is scheduled using a DCI format dedicated to the multicast PDSCH, the UE may also report UE capability information (UE Capability) related to whether the DCI format dedicated to the multicast PDSCH can be supported to the network (NW, for example, gNB). In this case, the combination of DCI sizes (payload size, number of bits) increases, the number of blind detections of DCI implemented by the UE increases, and the complexity of UE operation increases, so that only UEs that support the DCI format may monitor the DCI format.

[0125] In addition, when the multicast PDSCH is scheduled by DCI format 1_0, that is, when the reception of the multicast PDSCH is set by high-layer signaling and the DCI is scrambled by CRC by the RNTI dedicated to multicast / broadcast scheduling, the UE may control the reception process of the multicast PDSCH by replacing the field value included in the DCI format 1_0 with the multicast parameter without changing the size of the DCI format 1_0. In this case, the UE may also use the DCI format 1_0 that is not scrambled by CRC by the RNTI dedicated to multicast / broadcast scheduling for purposes other than scheduling of the multicast PDSCH.

[0126] In addition, when multicast PDSCH is scheduled through DCI format 1_0, that is, when the reception of multicast PDSCH is set through high-level signaling, the UE can also control the reception processing of multicast PDSCH by replacing the fields contained in the DCI format 1_0 with parameters for multicast without changing the size of DCI format 1_0.

[0127] When multicast PDSCH is scheduled via DCI format 1_0, the UE may also use at least one of the DCI format identifier field, frequency domain resource allocation field, time domain resource allocation field, mapping field from VRB to PRB, NDI field, RV field, HARQ process number field, and downlink allocation index field included in the fields in DCI format 1_0 in the scheduling of multicast PDSCH.

[0128] In addition, when the multicast PDSCH is scheduled through DCI format 1_0, the UE may not use the modulation and coding scheme (MCS) field in the scheduling of the multicast PDSCH among the fields included in the DCI format 1_0. In this case, the method of not using the MCS field described in the second embodiment in the scheduling of the multicast PDSCH may also be applied.

[0129] The DCI common to each UE is used to indicate the resource indication, timing (value) indication, and TPC command (value) indication method of the UE-specific PUCCH. In Rel.16NR, the TPC command field for the scheduled PUCCH has 2 bits, the PRI field has 3 bits, and the HARQ feedback timing indicator field has 3 bits.

[0130] When multicast PDSCH is scheduled through DCI format 1_0, the UE may not use at least one specific field of the TPC command field value, PRI field value, and HARQ feedback timing indicator field value for the scheduled PUCCH included in the fields in DCI format 1_0.

[0131] In this case, the UE may also assume that the value of a specific field indicated by DCI format 1_0 is ignored and a certain value is used. The certain value may be a value determined by a certain transformation formula for the value of the field indicated by DCI format 1_0, or a value notified to the UE by UE-specific higher layer signaling.

[0132] The UE may also assume that the resource / value to be used is determined by the bits transformed by a certain transformation formula. The transformation method based on the transformation formula will be described later in the field (resource / value) transformation method.

[0133] Furthermore, the UE may use resources / values ​​obtained by converting the resources / values ​​represented by the value of the field represented by DCI format 1_0 using a certain conversion formula.

[0134] In addition, the above transformation formula may also transform resources / values ​​using at least a UE-specific index / ID (e.g., C-RNTI). The transformation formula may also transform resources / values ​​using an offset value that is notified as UE-specific through high-layer signaling. In this case, for example, the UE may be notified of an offset such as an offset relative to the PRB index = +p, an offset relative to the initial CS index = +q (p, q are arbitrary values), and the UE determines the resource / value (e.g., PRB index, initial CS index, etc.) to be used by adding (or subtracting) the offset value from the index of the PUCCH resource indicated by the PRI / CCE index.

[0135] The UE may also not use at least one of the TPC command field, PRI field, and HARQ feedback timing indicator field for the scheduled PUCCH in the fields included in the DCI format 1_0 in the scheduling of the multicast PDSCH, regardless of whether the DCI format dedicated to the scheduling of the multicast PDSCH is specified, whether the RNTI dedicated to the scheduling of the multicast PDSCH is specified, and whether the fields included in the DCI format 1_0 are replaced. In this case, the UE can distinguish the DCI for scheduling the multicast PDSCH from the DCI for other PDSCHs by the presence or absence of at least one of the TPC command field, PRI field, and HARQ feedback timing indicator field for the scheduled PUCCH, and can effectively use the unused fields in the DCI for scheduling the multicast PDSCH for other purposes (for example, increase in the bit field of the TDRA / FDRA field).

[0136] When multicast PDSCH is scheduled by DCI format 1_0, the UE may not use the TPC command field for the scheduled PUCCH in the field included in DCI format 1_0 in scheduling the multicast PDSCH. In this case, the TPC command for the multicast PDSCH may be a certain value.

[0137] That is, the certain value may also be ±0. In other words, the UE may not assume closed loop (CL)-power control (PC). In addition, the certain value may be specified by a specification through a certain bit string (for example, bit 00), may be set through high-layer signaling, or may be a value reported to the NW as UE capability information (UE capability (UECapability)).

[0138] The UE may also not use the TPC command field in the field included in the DCI format 1_0 in the scheduling of the multicast PDSCH in a manner independent of whether the DCI format dedicated to the scheduling of the multicast PDSCH is specified, whether the RNTI dedicated to the scheduling of the multicast PDSCH is specified, and whether the field included in the DCI format 1_0 is replaced. In this case, the DCI for scheduling the multicast PDSCH and other PDSCHs can be distinguished, and the unused field in the DCI for scheduling the multicast PDSCH can be effectively used for other purposes (for example, increase in the bit field of the TDRA / FDRA field).

[0139] In this case, the UE may also use the TPC command field included in the DCI format 1_0 that is not used in the scheduling of the multicast PDSCH to switch at least one of the method for transforming the bit field value included in the DCI for each UE and the method for transforming the PUCCH resource. The method for transforming the bit field value included in the DCI for each UE and the method for transforming the PUCCH resource are described in detail below.

[0140] For example, a plurality of patterns (eg, four patterns) are predefined in the bit field (value) / PUCCH resource conversion rule for each UE, and the UE may determine one pattern from the plurality of patterns using the value of the TPC command field.

[0141] The determination of the mode may also be a mode corresponding to a value obtained by a certain transformation formula. The transformation formula may also be determined based on a UE-specific RNTI (e.g., C-RNTI). For example, the transformation formula may also be given by mod({value of UE-specific RNTI}, M) (M is an arbitrary integer). The value M used for the transformation formula may be predetermined by the specification or determined by high-level signaling. The value of M may be used to control the utilization efficiency of PUCCH resources and the possibility of PUCCH resource conflicts between UEs.

[0142] In addition, in the above, the method of using the TPC command field is described, but fields other than the TPC command field included in DCI format 1_0 (for example, the PRI field, the time indicator field from PDSCH to HARQ feedback), or high-level signaling can be used.

[0143] [Field (resource / value) conversion method]

[0144] The following describes a method for transforming a field value (resource / value represented by it) contained in a DCI common to multiple UEs into a UE-specific value (resource / value represented by it). The method described in detail here can also be appropriately applied in other embodiments. The transformation rule of the bit field (bit string) shown below can be notified to each UE through UE-specific high-layer signaling, and each UE can also make a judgment based on the UE index (RNTI).

[0145] The UE may also determine the resource / value to be used by the bits transformed by a certain transformation formula. For example, when the field value is X bits, the UE may also use a value determined by the following methods for the field value: an X-bit value notified by higher layer signaling, or at least one of addition, subtraction, and exclusive OR (EXOR) calculation of an X-bit value determined based on a UE index (RNTI).

[0146] In addition, the UE may also rearrange the field values ​​contained in the DCI common to multiple UEs based on a certain rule to determine the resource / value to be used. Regarding the rule, the rule may be notified to each UE through high-layer signaling, or the UE may make a judgment based on a UE index (eg, C-RNTI).

[0147] For example, when a 3-bit bit field (bit string) is notified to each UE, the first UE is notified to rearrange the bit positions (123) in the received bit string for use, and the second UE is notified to rearrange the bit positions (321) in the received bit string for use, and when the bit string received by the first UE and the second UE is

[110] , the first UE determines the bit string to be used to be

[110] , and the second UE determines the bit string to be used to be

[011] .

[0148] For example, when a 3-bit bit field (bit string) is notified to each UE and the UE judges the rule based on the UE index (e.g., C-RNTI), the first UE may also judge to use the bits in the received bit string in the order of (123), and the second UE may also be notified to rearrange the bits in the received bit string in the order of (321) for use.

[0149] Regarding the rules for rearrangement (transformation) of the above-mentioned bit fields, the UE may also assume that only specific bit fields (e.g., TPC command field, PRI field, HARQ feedback timing indicator field for scheduled PUCCH) are specified. In addition, regarding the rules for rearrangement of the above-mentioned bit fields, the UE may be individually set for each specific bit field, or may be set for bit rearrangement rules for variable bit lengths.

[0150] In addition, regarding the field value included in the DCI common to multiple UEs, the UE may also determine the number of bits to be used based on a certain rule.

[0151] In this case, for example, when a certain bit field (bit string) is notified to multiple UEs (a first UE and a second UE), the first UE may be assumed to use all the notified bits, and the other UEs may be assumed to use the upper (most significant, from the left, or lower (least significant, from the right)) 2 bits of the notified bits. For example, when the bit string received by the first UE and the second UE is

[111] , the first UE may determine the bit string to be used to be

[111] , and the second UE may determine that the received bit string is

[11] and determine the bit string to be used to be

[011] .

[0152] In addition, each UE may also determine the resource / value used in the PUCCH by replacing at least one of the following bit fields:

[0153] ·DCI bit field,

[0154] The minimum / maximum CCE index (PRB / RE index) of the PDCCH carrying the DCI,

[0155] PDCCH (CCE) aggregation level,

[0156] Search space index,

[0157] CORESET index,

[0158] The PRG (PRB) index of the start / end of the PDSCH,

[0159] Number of MIMO layers for PDSCH.

[0160] In addition, among the above fields, the fields used by the UE may be set to the UE through higher layer signaling, or may be determined by a rule based on a UE index (for example, C-RNTI).

[0161] In this case, a certain UE determines the PUCCH resources to be used based on the bit field of DCI, while other UEs determine the PUCCH resources to be used based on both the bit field of DCI and the CCE index. Therefore, even if the common DCI (DCI bit field) is notified to each UE, different PUCCH resources for each UE can be used for HARQ-ACK transmission.

[0162] According to the third embodiment described above, it is possible to suppress an increase in the overhead of DCI notified to a plurality of UEs and avoid overlapping of PUSCH / PUCCH transmission resources, thereby enabling appropriate communication.

[0163] <Fourth embodiment>

[0164] In the fourth embodiment, a situation in which multiple UEs use non-orthogonal UL resources to send HARQ-ACK is described. Specifically, the following situation is described: each UE receives a DCI common to multiple UEs / UE-specific, and the DCI schedules a PDSCH (multicast PDSCH) common to multiple UEs. Through the DCI, each UE is instructed (determined) to use the time and frequency resources of the PUCCH / PUSCH for sending the HARQ-ACK corresponding to the multicast PDSCH. In addition, in this embodiment, at least one of the second embodiment and the third embodiment described above can also be applied to a part of the multiple UEs.

[0165] In this embodiment, a case where each UE receives a DCI common to multiple UEs is described, but the content of this embodiment is also applicable to a case where each UE receives a UE-specific DCI. In addition, the case where the PUCCH in this embodiment is a sequence-based PUCCH (e.g., PF0) is described. Sequence-based PUCCH and PUCCH without DMRS can also be replaced with each other.

[0166] Figure 5 FIG. 1 is a diagram showing an example of a multicast PDSCH reception process. Figure 5 In the present invention, a certain UE monitors the DCI (DCI1) common to each UE and receives the multicast PDSCH, and uses the PUCCH resources (PUCCH1) common to multiple UEs to send the HARQ-ACK corresponding to the multicast PDSCH.

[0167] in addition, Figure 5 The number of DCI and PUCCH resources and the time / frequency allocation positions shown are just examples and the present invention is not limited to these examples.

[0168] In the transmission of HARQ-ACK, two (ACK and NACK) resources (PRB or RE) are reserved in order to send 1 bit of HARQ-ACK. In the case where multiple UEs send HARQ-ACK corresponding to multicast PDSCH in a common PUCCH resource, the HARQ-ACK resources sent by multiple UEs may overlap (overlap) according to the number of UEs or the size of PUCCH resources. In addition, in the case where multiple UEs send HARQ-ACK in a common PUCCH resource and the HARQ-ACK resources sent by multiple UEs do not overlap, the PUCCH resources are compressed.

[0169] Therefore, a method of overlapping a plurality of HARQ-ACK resources (at least one of ACK resources and NACK resources) respectively used by a plurality of UEs in the time domain and the frequency domain will be described below.

[0170] When HARQ-ACK corresponding to the multicast PDSCH is transmitted in the PUCCH resources common to multiple UEs, the UE may transmit the HARQ-ACK assuming that the ACK resources allocated to the multiple UEs overlap.

[0171] In other words, in the HARQ-ACK corresponding to the multicast PDSCH, each UE uses overlapping ACK resources to send ACK when the reception processing (for example, demodulation, decoding, etc.) of the multicast PDSCH is successful, and sends NACK in non-overlapping NACK resources when the reception processing of the multicast PDSCH fails.

[0172] Figure 6 This is a diagram showing an example of a method of transmitting HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to a plurality of UEs. Figure 6 A block of resources in can be either a PRB or an RE (or subcarrier). Figure 6 In the case where HARQ-ACK corresponding to the multicast PDSCH is transmitted in the PUCCH resources common to multiple UEs (UE1-4), the ACK resources allocated to each UE are overlapped and the NACK resources allocated to each UE are not overlapped.

[0173] in addition, Figure 6 The number of UEs and ACK / NACK transmission resources shown are just examples, and the present invention is not limited to these examples.

[0174] The operation of the side receiving HARQ-ACK (ACK and NACK) transmitted from a plurality of UEs in this case will be described. In the present disclosure, the HARQ-ACK receiving side is described as NW, but the present invention is not limited to this.

[0175] NW can also detect whether multiple UEs have sent ACKs based on the received power of ACKs sent from multiple UEs in overlapping resources. When the received power of ACKs sent from multiple UEs is above the threshold (larger than the threshold), NW can also determine that all multiple UEs have succeeded in the reception process of multicast PDSCH without retransmitting multicast PDSCH. The threshold can also be a value that can estimate that multiple UEs have all sent ACKs. On the other hand, when the received power of ACKs sent from multiple UEs is less than the threshold (below the threshold), NW can also determine that there are UEs that have failed to receive the multicast PDSCH and retransmit the multicast PDSCH.

[0176] In addition, in the case where the ACK resources allocated to multiple UEs overlap, NACK resources may not be allocated to multiple UEs. In this case, a UE that successfully receives and processes the multicast PDSCH among multiple UEs may also send ACK using the ACK transmission resources that overlap with the ACK transmission resources of other UEs, and a UE that fails to receive and process the multicast PDSCH may not send NACK.

[0177] Fig. 7A as well as Figure 7B 1 is a diagram showing an example of HARQ-ACK detection sent from multiple UEs in the NW. Fig. 7A In the example, all of the multiple UEs (UE1-4) use overlapping resources to send ACK. At this time, the NW measures the received power of the ACK ( Figure 7B ), when it is estimated that the number of UEs that have sent ACK is 4, it is determined that all of the multiple UEs have succeeded in the reception processing of the multicast PDSCH, and the multicast PDSCH is not retransmitted.

[0178] in addition, Fig. 7A as well as Figure 7B The number of UEs, ACK / NACK transmission resources, and ACK / NACK reception power based on NW shown are just examples, and the present invention is not limited to these examples.

[0179] Furthermore, when HARQ-ACK corresponding to the multicast PDSCH is transmitted in a PUCCH resource common to a plurality of UEs, the UE may transmit HARQ-ACK assuming that NACK resources allocated to the plurality of UEs overlap.

[0180] In the case where NACK resources allocated to multiple UEs overlap, ACK resources may not be allocated to multiple UEs. In other words, each UE may send NACK through overlapping resources in the HARQ-ACK corresponding to the multicast PDSCH when the reception processing of the multicast PDSCH fails, and not send ACK when the reception processing of the multicast PDSCH succeeds.

[0181] The NW may also detect whether multiple UEs have sent NACKs based on the received power of NACKs sent from multiple UEs in overlapping resources. When NACK transmission from at least one UE is detected, the NW may also determine that there is a UE that has failed to receive the multicast PDSCH and retransmit the multicast PDSCH. In addition, when NACK transmission from at least one UE is not detected, the NW may also determine that all multiple UEs have succeeded in receiving the multicast PDSCH and do not retransmit the multicast PDSCH.

[0182] Figure 8A-8C This is a diagram showing an example of a method of transmitting HARQ-ACK corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs and an example of detecting HARQ-ACK transmitted from multiple UEs in a NW. Fig. 8A In the above, a UE that fails in receiving the multicast PDSCH among the plurality of UEs (UE1-4) transmits NACK using resources that overlap with NACK transmission resources of other UEs. A UE that succeeds in receiving the multicast PDSCH transmits ACK.

[0183] At this time, the NW measures the reception power of the NACK and estimates that there is only one UE that has sent the NACK. It determines that any UE has failed in the reception process of the multicast PDSCH and retransmits the multicast PDSCH. Figure 8B In the example shown, the NW measures the received power of the NACK, estimates that there are no UEs that have sent NACK, and does not retransmit the multicast PDSCH. Figure 8C In the example shown, when the NW measures the reception power of the NACK and estimates that the number of UEs that have transmitted the NACK is one or more, the NW retransmits the multicast PDSCH.

[0184] exist Fig. 8A In the multicast PDSCH, NACK resources may be allocated but ACK resources may not be allocated. In this case, a UE that fails in the multicast PDSCH reception process among multiple UEs (UE1-4) sends NACK using resources that overlap with NACK transmission resources of other UEs. A UE that succeeds in the multicast PDSCH reception process does not send ACK.

[0185] in addition, Figure 8A-8C The number of UEs, ACK / NACK transmission resources, and ACK / NACK reception power based on NW shown are just examples, and the present invention is not limited to these examples.

[0186] In addition, in the reception of multicast PDSCH, if the reception processing of the PDSCH fails, each UE may also send PUCCH (NACK). In this case, in the reception of multicast PDSCH, if the reception processing of the PDSCH succeeds, each UE may not send PUCCH (ACK).

[0187] In this case, the NW can determine the existence of the UE that sends NACK based on the received power of the PUCCH. In other words, when the NW does not receive the NACK, the NW can determine that multiple UEs have successfully received the PDSCH. In addition, when at least one UE sends a NACK, the NW can also perform HARQ retransmission control. In this case, when each UE is assigned a different DMRS sequence (or at least one of a cyclic shift and an orthogonal cover code (Orthogonal Cover Code (OCC))), the NW can also determine the UE that needs to retransmit the PDSCH based on the DMRS sequence (or at least one of a cyclic shift and an orthogonal cover code (Orthogonal Cover Code (OCC))). In addition, when the NW cannot determine the UE that needs to retransmit the PDSCH, the PDSCH can also be retransmitted to multiple UEs.

[0188] In this case, even if there is a UE that cannot recognize reception of the multicast PDSCH, more efficient communication can be implemented because the error rate of DCI (about 1%) is smaller than the error rate of PDSCH (about 10%).

[0189] As mentioned above Fig. 7A In this way, when receiving a multicast PDSCH, each UE may send a PUCCH (ACK) if the reception process of the PDSCH succeeds. In this case, when receiving a multicast PDSCH, each UE may not send a PUCCH (NACK) if the reception process of the PDSCH fails.

[0190] In this case, when the received power of ACK sent from multiple UEs is above the threshold (larger than the threshold), the NW may also determine that all multiple UEs succeeded in the reception process of the multicast PDSCH and do not retransmit the multicast PDSCH. The threshold may also be a value that can estimate that all multiple UEs have sent ACKs. On the other hand, when the received power of ACK sent from multiple UEs is less than the threshold (below the threshold), the NW may also determine that there is a UE that failed in the reception process of the multicast PDSCH and retransmit the multicast PDSCH.

[0191] In this case, communications with assured reliability can be performed on all of the plurality of UEs.

[0192] Fig. 9A as well as Fig. 9B FIG. 1 is a diagram showing an example of a method of transmitting HARQ-ACK (PUCCH) corresponding to a multicast PDSCH in a PUCCH resource common to multiple UEs. Fig. 9A In the case of a failure in the reception process of the PDSCH, each UE sends a PUCCH (NACK). Fig. 9B In the case where the reception processing of the PDSCH is successful, each UE does not send a PUCCH (ACK).

[0193] in addition, Fig. 9A as well as Fig. 9B The number of DCI, PDSCH, and PUCCH resources and their time / frequency allocation positions shown are merely examples, and the present invention is not limited to these examples.

[0194] In addition, the PUCCH transmitted in this embodiment is not limited to the sequence-based PUCCH (e.g., PUCCH of PF0), but may also be PUCCH or PUSCH of other formats (e.g., PF1-4, PUCCH with DMRS). Based on the PF applied in the PUCCH, for the multicast PDSCH, the UE may determine to send NACK instead of ACK as described above, or may determine to send ACK instead of NACK.

[0195] As described above, according to the fourth embodiment, a plurality of UEs can appropriately transmit HARQ-ACK using non-orthogonal UL resources, and can suppress a decrease in uplink resource utilization efficiency.

[0196] (Wireless Communication System)

[0197] Hereinafter, a configuration of a wireless communication system according to an embodiment of the present disclosure will be described. In the wireless communication system, communication is performed using one of the wireless communication methods according to the above-mentioned embodiments of the present disclosure or a combination thereof.

[0198] Fig.10 1 is a diagram showing an example of a schematic structure of a wireless communication system involved in one embodiment. The wireless communication system 1 may also be a system that implements communication using Long Term Evolution (LTE) standardized by the Third Generation Partnership Project (3GPP), the fifth generation mobile communication system New Radio (5G NR), and the like.

[0199] In addition, the wireless communication system 1 can also support dual connectivity (Multi-RAT Dual Connectivity (MR-DC)) between multiple radio access technologies (Radio Access Technology (RAT)). MR-DC can also include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA))) and NR (E-UTRA-NR Dual Connectivity (E-UTRA-NR Dual Connectivity (EN-DC))), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NR-E-UTRA Dual Connectivity (NE-DC))), etc.

[0200] In EN-DC, the base station (eNB) of LTE (E-UTRA) is the master node (Master Node (MN)), and the base station (gNB) of NR is the secondary node (Secondary Node (SN)). In NE-DC, the base station (gNB) of NR is the MN, and the base station (eNB) of LTE (E-UTRA) is the SN.

[0201] The wireless communication system 1 can also support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity (NR-NR Dual Connectivity (NN-DC)) where both MN and SN are NR base stations (gNB)).

[0202] The wireless communication system 1 may also include: a base station 11 that forms a macro cell C1 with a relatively wide coverage, and a base station 12 (12a-12c) that is configured in the macro cell C1 and forms a small cell C2 that is narrower than the macro cell C1. The user terminal 20 may also be located in at least one cell. The configuration and number of each cell and the user terminal 20 are not limited to the method shown in the figure. Hereinafter, when the base stations 11 and 12 are not distinguished, they are collectively referred to as the base station 10.

[0203] The user terminal 20 may be connected to at least one of the plurality of base stations 10. The user terminal 20 may use at least one of carrier aggregation (CA) using a plurality of component carriers (CC) and dual connectivity (DC).

[0204] Each CC may also be included in at least one of the first frequency band (Frequency Range 1 (FR1)) and the second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may also be included in FR1, and the small cell C2 may also be included in FR2. For example, FR1 may be a frequency band below 6 GHz (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). In addition, the frequency bands and definitions of FR1 and FR2 are not limited to this. For example, FR1 may also correspond to a frequency band higher than FR2.

[0205] Furthermore, in each CC, the user terminal 20 may communicate using at least one of time division duplex (TDD) and frequency division duplex (FDD).

[0206] Multiple base stations 10 may also be connected by wire (e.g., optical fiber based on Common Public Radio Interface (CPRI)), X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication between base stations 11 and 12 is used as a backhaul, the base station 11 equivalent to the upper station may also be referred to as an Integrated Access Backhaul (IAB) donor, and the base station 12 equivalent to a relay station may also be referred to as an IAB node.

[0207] The base station 10 may also be connected to the core network 30 via other base stations 10 or directly. The core network 30 may also include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0208] The user terminal 20 may also be a terminal that supports at least one of communication modes such as LTE, LTE-A, and 5G.

[0209] In the wireless communication system 1, a wireless access method 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.

[0210] The radio access scheme may also be referred to as a waveform. In addition, in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be applied to the UL and DL radio access schemes.

[0211] As downlink channels, the wireless communication system 1 may use 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.

[0212] In addition, as uplink channels, 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)) and the like can also be used in the wireless communication system 1.

[0213] The PDSCH is used to transmit user data, high-layer control information, system information block (SIB), etc. The PUSCH is also used to transmit user data, high-layer control information, etc. In addition, the PBCH is also used to transmit the master information block (MIB).

[0214] The lower layer control information may also be transmitted via the PDCCH. The lower layer control information may include, for example, downlink control information (Downlink Control Information (DCI)) including scheduling information of at least one of the PDSCH and the PUSCH.

[0215] In addition, the DCI that schedules the PDSCH may also be referred to as DL allocation, DL DCI, etc., and the DCI that schedules the PUSCH may also be referred to as UL grant, UL DCI, etc. In addition, the PDSCH may also be replaced by DL data, and the PUSCH may also be replaced by UL data.

[0216] In the detection of PDCCH, the control resource set (CORESET) and the search space can also be used. CORESET corresponds to the resources for searching DCI. The search space corresponds to the search area and search method of PDCCH candidates. A CORESET can also be associated with one or more search spaces. The UE can also monitor the CORESET associated with a search space based on the search space setting.

[0217] A search space may also correspond to PDCCH candidates that are consistent with one or more aggregation levels. One or more search spaces may also be referred to as a search space set. In addition, the "search space", "search space set", "search space setting", "search space set setting", "CORESET", "CORESET setting" and the like in the present disclosure may also be interchangeable.

[0218] Uplink control information (uplink control information (UCI)) including at least one of channel state information (CSI), delivery confirmation information (e.g., may also be called hybrid automatic repeat request confirmation (HARQ-ACK), ACK / NACK, etc.), and scheduling request (Scheduling Request (SR)) may also be transmitted through PUCCH. Random access preamble code for establishing connection with a cell may also be transmitted through PRACH.

[0219] In the present disclosure, downlink, uplink, etc. may be expressed without the word “link.” In addition, various channels may be expressed without the word “physical” at the beginning.

[0220] In the wireless communication system 1, a synchronization signal (Synchronization Signal (SS)), a downlink reference signal (Downlink Reference Signal (DL-RS)), etc. can also be transmitted. As DL-RS, in the wireless communication system 1, a cell-specific reference signal (Cell-specific Reference Signal (CRS)), a channel state information reference signal (Channel State Information Reference Signal (CSI-RS)), a demodulation reference signal (DeModulation Reference Signal (DMRS)), a positioning reference signal (Positioning Reference Signal (PRS)), a phase tracking reference signal (Phase Tracking Reference Signal (PTRS)), etc. can also be transmitted.

[0221] 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 SS (PSS, SSS) and PBCH (and DMRS for PBCH) may also be referred to as SS / PBCH block, SS block (SSB), etc. In addition, SS, SSB, etc. may also be referred to as reference signals.

[0222] In addition, in the wireless communication system 1, as an uplink reference signal (Uplink Reference Signal (UL-RS)), a measurement reference signal (Sounding Reference Signal (SRS)), a demodulation reference signal (DMRS), etc. can also be transmitted. In addition, DMRS can also be called a user terminal specific reference signal (UE-specific Reference Signal).

[0223] (Base Station)

[0224] Fig.11 1 is a diagram showing an example of a structure of a base station involved in one embodiment. The base station 10 includes a control unit 110, a transmitting and receiving unit 120, a transmitting and receiving antenna 130, and a transmission path interface (transmission line interface) 140. In addition, the control unit 110, the transmitting and receiving unit 120, the transmitting and receiving antenna 130, and the transmission path interface 140 may each be provided with more than one.

[0225] In addition, in this example, the functional blocks of the characteristic parts of this embodiment are mainly shown, and it is also assumed that the base station 10 also has other functional blocks required for wireless communication. Part of the processing of each unit described below may be omitted.

[0226] The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, a control circuit, and the like that are described based on the common knowledge in the technical field to which the present disclosure relates.

[0227] The control unit 110 may also control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may also control transmission and reception, measurement, etc. using the transmission and reception unit 120, the transmission and reception antenna 130, and the transmission path interface 140. The control unit 110 may also generate data, control information, sequences, etc. to be sent as signals, and forward them to the transmission and reception unit 120. The control unit 110 may also perform call processing (setting, release, etc.) of communication channels, state management of the base station 10, management of wireless resources, etc.

[0228] The transmitting and receiving unit 120 may also include a baseband unit 121, a radio frequency (RF) unit 122, and a measuring unit 123. The baseband unit 121 may also include a transmitting processing unit 1211 and a receiving processing unit 1212. The transmitting and receiving unit 120 may be composed of a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter (phase shifter), a measuring circuit, a transmitting and receiving circuit, etc., which are described based on the public knowledge in the technical field involved in the present disclosure.

[0229] The transmitting and receiving unit 120 may be configured as an integrated transmitting and receiving unit, or may be configured as a transmitting unit and a receiving unit. The transmitting unit may also be configured as a transmitting processing unit 1211 and an RF unit 122. The receiving unit may also be configured as a receiving processing unit 1212, an RF unit 122, and a measuring unit 123.

[0230] The transmitting / receiving antenna 130 can be constituted by an antenna described based on the common knowledge in the technical field involved in the present disclosure, such as an array antenna.

[0231] The transmitting and receiving unit 120 may also transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transmitting and receiving unit 120 may also receive the above-mentioned uplink channel, uplink reference signal, etc.

[0232] The transmitting and receiving unit 120 may also use digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), etc. to form at least one of a transmitting beam and a receiving beam.

[0233] The sending and receiving unit 120 (sending processing unit 1211), for example, may also perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (for example, RLC retransmission control), Medium Access Control (MAC) layer processing (for example, HARQ retransmission control), etc. on the data, control information, etc. obtained from the control unit 110, to generate a bit string to be sent.

[0234] The transmitting and receiving unit 120 (transmitting processing unit 1211) can also perform channel coding (which may also include error correction coding), modulation, mapping, filter processing, discrete Fourier transform (DFT) processing (as needed), inverse fast Fourier transform (IFFT) processing), precoding, digital-to-analog conversion and other transmission processing on the bit string to be sent, and output a baseband signal.

[0235] The transmitting and receiving unit 120 (RF unit 122 ) may also perform modulation, filter processing, amplification, etc. on the baseband signal to a radio frequency band, and transmit the signal in the radio frequency band via the transmitting and receiving antenna 130 .

[0236] On the other hand, the transmitting and receiving unit 120 (RF unit 122 ) may perform amplification, filter processing, demodulation into a baseband signal, etc. on the signal in the radio frequency band received by the transmitting and receiving antenna 130 .

[0237] For the acquired baseband signal, the transmitting and receiving unit 120 (receiving processing unit 1212) can also apply analog-to-digital conversion, fast Fourier transform (FFT) processing, inverse discrete Fourier transform (IDFT) processing (as needed), filter processing, demapping, demodulation, decoding (which may also include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing, etc. to obtain user data, etc.

[0238] The transmitting and receiving unit 120 (measuring unit 123) may also implement measurements related to the received signal. For example, the measuring unit 123 may also perform radio resource management (Radio Resource Management (RRM)) measurements, channel state information (CSI) measurements, etc. based on the received signal. The measuring unit 123 may also measure received power (e.g., reference signal received power (Reference Signal Received Power (RSRP))), received quality (e.g., reference signal received quality (Reference Signal Received Quality (RSRQ)), signal to interference plus noise ratio (Signal to Interference plus Noise Ratio (SINR)), signal to noise ratio (Signal to Noise Ratio (SNR))), signal strength (e.g., received signal strength indicator (Received Signal Strength Indicator (RSSI))), propagation path information (e.g., CSI), etc. The measurement results may also be output to the control unit 110.

[0239] The transmission path interface 140 can also send and receive signals (return signaling) between the devices included in the core network 30, other base stations 10, etc., and can also obtain and transmit user data (user plane data) and control plane data for the user terminal 20.

[0240] In addition, the transmitting unit and the receiving unit of the base station 10 in the present disclosure may also be constituted by at least one of the transmitting and receiving unit 120 , the transmitting and receiving antenna 130 , and the transmission path interface 140 .

[0241] The transmitting and receiving unit 120 may also transmit downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 110 may also control reception of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI (first and second embodiments).

[0242] The transmitting and receiving unit 120 may also transmit downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 110 may also be a control unit for controlling the reception of a hybrid automatic repeat request acknowledgment (HARQ-ACK) for the downlink shared channel based on the DCI. The DCI may also be common to multiple terminals (first and third embodiments).

[0243] The transmitting and receiving unit 120 may also transmit downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 110 may also determine the time and frequency resources for receiving a hybrid automatic repeat request confirmation (Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK)) for the downlink shared channel based on the DCI. The resources may also overlap with at least a portion of the resources used by multiple terminals (first and fourth embodiments).

[0244] (User Terminal)

[0245] Fig.12 The user terminal 20 includes a control unit 210, a transmission / reception unit 220, and a transmission / reception antenna 230. In addition, the control unit 210, the transmission / reception unit 220, and the transmission / reception antenna 230 may be provided in one or more pieces.

[0246] In addition, in this example, the functional blocks of the characteristic parts in this embodiment are mainly shown, and it is also assumed that the user terminal 20 also has other functional blocks required for wireless communication. Part of the processing of each unit described below may be omitted.

[0247] The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, a control circuit, and the like that are described based on the common knowledge in the technical field to which the present disclosure relates.

[0248] The control unit 210 may also control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc. using the transmission and reception unit 220 and the transmission and reception antenna 230. The control unit 210 may also generate data, control information, sequences, etc. to be transmitted as signals, and forward them to the transmission and reception unit 220.

[0249] The transmitting and receiving unit 220 may also include a baseband unit 221, an RF unit 222, and a measuring unit 223. The baseband unit 221 may also include a transmitting processing unit 2211 and a receiving processing unit 2212. The transmitting and receiving unit 220 may be composed of a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measuring circuit, a transmitting and receiving circuit, etc., which are described based on the public knowledge in the technical field involved in the present disclosure.

[0250] The transmitting and receiving unit 220 may be configured as an integrated transmitting and receiving unit, or may be configured as a transmitting unit and a receiving unit. The transmitting unit may also be configured as a transmitting processing unit 2211 and an RF unit 222. The receiving unit may also be configured as a receiving processing unit 2212, an RF unit 222, and a measuring unit 223.

[0251] The transmitting / receiving antenna 230 can be constituted by an antenna described based on the common knowledge in the technical field involved in the present disclosure, such as an array antenna.

[0252] The transmitting and receiving unit 220 may also receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transmitting and receiving unit 220 may also transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0253] The transmitting and receiving unit 220 may also use digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), etc. to form at least one of a transmitting beam and a receiving beam.

[0254] The sending and receiving unit 220 (sending processing unit 2211), for example, can also perform PDCP layer processing, RLC layer processing (for example, RLC retransmission control), MAC layer processing (for example, HARQ retransmission control), etc. on the data, control information, etc. obtained from the control unit 210 to generate a bit string to be sent.

[0255] The transmitting and receiving unit 220 (transmitting processing unit 2211) can also perform channel coding (which may also include error correction coding), modulation, mapping, filter processing, DFT processing (as needed), IFFT processing, precoding, digital-to-analog conversion and other transmission processing on the bit string to be sent, and output a baseband signal.

[0256] In addition, whether to apply DFT processing may also be based on the setting of transform precoding. For a certain channel (e.g., PUSCH), when transform precoding is valid (enabled), the transmitting and receiving unit 220 (transmitting processing unit 2211) may also perform DFT processing as the above-mentioned transmission processing in order to transmit the channel using a DFT-s-OFDM waveform. Otherwise, the transmitting and receiving unit 220 (transmitting processing unit 2211) may also perform DFT processing as the above-mentioned transmission processing without performing DFT processing.

[0257] The transmitting and receiving unit 220 (RF unit 222 ) may also perform modulation, filter processing, amplification, etc. on the baseband signal to a radio frequency band, and transmit the signal in the radio frequency band via the transmitting and receiving antenna 230 .

[0258] On the other hand, the transmitting and receiving unit 220 (RF unit 222 ) may perform amplification, filter processing, demodulation to a baseband signal, etc. on the signal in the radio frequency band received by the transmitting and receiving antenna 230 .

[0259] The sending and receiving unit 220 (receiving processing unit 2212) can also apply analog-to-digital conversion, FFT processing, IDFT processing (as needed), filter processing, demapping, demodulation, decoding (which may also include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to obtain user data, etc.

[0260] The transmitting and receiving unit 220 (measuring unit 223) may also perform measurements related to the received signal. For example, the measuring unit 223 may also perform RRM measurements, CSI measurements, etc. based on the received signal. The measuring unit 223 may also 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 also be output to the control unit 210.

[0261] In addition, the transmitting unit and the receiving unit of the user terminal 20 in the present disclosure may also be constituted by at least one of the transmitting and receiving unit 220 and the transmitting and receiving antenna 230 .

[0262] The transmitting and receiving unit 220 may also receive downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 210 may also control the transmission of a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for the downlink shared channel based on the DCI (first and second embodiments).

[0263] The control unit 210 may determine the time and frequency resources used for transmitting the HARQ-ACK based on the DCI. The resources may not overlap with the uplink control channel (PUCCH) resources transmitted by other terminals (second embodiment).

[0264] When multicast is set by higher layer signaling and the DCI is encrypted by a specific radio 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).

[0265] The specific field may also be a modulation and coding scheme field (second embodiment).

[0266] The transmitting and receiving unit 220 may also receive downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 210 may also control the transmission of a hybrid automatic repeat request acknowledgment (HARQ-ACK) for the downlink shared channel based on the DCI. The DCI may also be common to multiple terminals (first and third embodiments).

[0267] The control unit 210 may determine the time and frequency resources used for transmitting the HARQ-ACK based on the DCI. The resources may not overlap with the uplink control channel (PUCCH) resources transmitted by other terminals (third embodiment).

[0268] When the resources used to transmit the HARQ-ACK are resources based on a setting grant, the control unit 210 may determine to transmit the HARQ-ACK (third embodiment).

[0269] When multicast is set by higher-layer signaling and the DCI is encrypted by a specific radio network temporary identifier, the control unit 210 may control the reception processing of the downlink shared channel by replacing (interpreting) a specific field included in the DCI as a parameter for multicast (third embodiment).

[0270] The transmitting and receiving unit 220 may also receive downlink control information (DCI) of a downlink shared channel for scheduling multicast. The control unit 210 may also determine the time and frequency resources for sending a hybrid automatic repeat request confirmation (Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK)) for the downlink shared channel based on the DCI. The resources may also overlap with at least a portion of the resources used by other terminals (first and fourth embodiments).

[0271] The control unit 210 may also perform control so that an acknowledgement (ACK) to the downlink shared channel is transmitted using a resource overlapping with an ACK from another terminal among the resources (fourth embodiment).

[0272] The control unit 210 may perform control so that a negative acknowledgement (NACK) for the downlink shared channel is transmitted using a resource overlapping with a NACK from another terminal among the resources (fourth embodiment).

[0273] 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).

[0274] (Hardware Structure)

[0275] In addition, the block diagram used in the description of the above-mentioned embodiment shows a block of a functional unit. These functional blocks (structural units) are implemented by any combination of at least one of hardware and software. In addition, the implementation method of each functional block is not particularly limited. That is, each functional block can be implemented by a device that is physically or logically combined, or two or more devices that are physically or logically separated can be directly or indirectly (for example, by wired, wireless, etc.) connected and implemented by these multiple devices. The functional block can also be implemented by combining the above-mentioned one device or the above-mentioned multiple devices with software.

[0276] Here, the functions include judging, deciding, determining, calculating, calculating, processing, deriving, investigating, searching, confirming, receiving, sending, outputting, accessing, solving, selecting, selecting, establishing, comparing, assuming, expecting, regarding, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but are not limited to these. For example, a functional block (structural unit) that implements a sending function may also be referred to as a transmitting unit, a transmitter, etc. Any one of them is as described above, and the implementation method is not particularly limited.

[0277] For example, a base station, a user terminal, etc. in one embodiment of the present disclosure may also function as a computer that performs processing of the wireless communication method of the present disclosure. Fig.13 1001, memory 1002, storage 1003, communication device 1004, input device 1005, output device 1006, bus 1007, etc.

[0278] In addition, in the present disclosure, the terms such as device, circuit, equipment, section, unit, etc. are interchangeable. The hardware structure of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the figure, or may be configured to exclude some of the devices.

[0279] For example, only one processor 1001 is shown, but there may be multiple processors. In addition, the processing may be performed by one processor, or may be performed by two or more processors simultaneously, sequentially, or in other ways. In addition, the processor 1001 may also be implemented by one or more chips.

[0280] The functions of the base station 10 and the user terminal 20 are realized, for example, by reading specific software (program) into hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs calculations and controls communication via the communication device 1004, or controls at least one of the reading and writing of data in the memory 1002 and the storage 1003.

[0281] The processor 1001 controls the entire computer by, for example, operating an operating system. The processor 1001 may also be composed of a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), the sending and receiving unit 120 (220), etc. may also be implemented by the processor 1001.

[0282] In addition, the processor 1001 reads the program (program code), software module, data, etc. from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and performs various processes based on them. As a program, a program that enables a computer to perform at least a part of the operations described in the above-mentioned embodiments can be used. For example, the control unit 110 (210) can also be implemented by a control program stored in the memory 1002 and operated in the processor 1001, and the same can be implemented for other functional blocks.

[0283] The memory 1002 may also be a computer-readable recording medium, for example, composed of at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), and other appropriate storage media. The memory 1002 may also be referred to as a register, a cache, a main memory (main storage device), etc. The memory 1002 can store executable programs (program codes), software modules, etc. for implementing the wireless communication method involved in one embodiment of the present disclosure.

[0284] The storage 1003 may also be a computer-readable recording medium, such as a flexible disk, a floppy disk, an optical disk (such as a compact disk (Compact Disc ROM (CD-ROM)), etc.), a digital versatile disk, a Blu-ray (registered trademark) disk, a removable disk, a hard disk drive, a smart card, a flash memory device (such as a card, a stick, a key drive), a magnetic stripe, a database, a server, or at least one of other appropriate storage media. The storage 1003 may also be referred to as an auxiliary storage device.

[0285] The communication device 1004 is hardware (transmitting and receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also called a network device, a network controller, a network card, a communication module, etc. In order to realize at least one of frequency division duplex (Frequency Division Duplex (FDD)) and time division duplex (Time Division Duplex (TDD)), the communication device 1004 can also be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. For example, the above-mentioned transmitting and receiving unit 120 (220), the transmitting and receiving antenna 130 (230), etc. can also be realized by the communication device 1004. The transmitting and receiving unit 120 (220) can also be realized by physically or logically separating the transmitting unit 120a (220a) and the receiving unit 120b (220b).

[0286] The input device 1005 is an input device that receives input from the outside (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.). The output device 1006 is an output device that implements output to the outside (e.g., a display, a speaker, a light emitting diode (LED) lamp, etc.). In addition, the input device 1005 and the output device 1006 may also be an integrated structure (e.g., a touch panel).

[0287] In addition, the processor 1001, the memory 1002 and other devices are connected via a bus 1007 for communicating information. The bus 1007 may be configured as a single bus or different buses may be used between the devices.

[0288] In addition, the base station 10 and the user terminal 20 may also 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), and a field programmable gate array (FPGA), and the hardware may be used to implement a part or all of each functional block. For example, the processor 1001 may also be implemented using at least one of these hardware.

[0289] (Variation Example)

[0290] In addition, the terms described in the present disclosure and the terms required for understanding the present disclosure may also be replaced with terms having the same or similar meanings. For example, channels, code elements, and signals (signals or signaling) may also be replaced with each other. In addition, a signal may also be a message. A reference signal may also be referred to as RS, and may also be referred to as a pilot, a pilot signal, etc. depending on the standard applied. In addition, a component carrier (CC) may also be referred to as a cell, a frequency carrier, a carrier frequency, etc.

[0291] A wireless frame may also be composed of one or more periods (frames) in the time domain. Each period (frame) of the one or more periods (frames) constituting a wireless frame may also be referred to as a subframe. Further, a subframe may also be composed of one or more time slots in the time domain. A subframe may also be a fixed time length (e.g., 1 ms) that is not dependent on a parameter set (numerology).

[0292] Here, the parameter set may also refer to a communication parameter applied in at least one of the transmission and reception of a certain signal or channel. For example, the parameter set may also represent at least one of the subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), the number of symbols per TTI, wireless frame structure, specific filtering processing performed by the transmitter and receiver in the frequency domain, specific windowing processing performed by the transmitter and receiver in the time domain, etc.

[0293] A time slot may also be composed of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) in the time domain. In addition, a time slot may also be a time unit based on a parameter set.

[0294] A time slot may also include multiple mini-slots. Each mini-slot may also be composed of one or more symbols in the time domain. In addition, a mini-slot may also be referred to as a sub-slot. A mini-slot may also be composed of fewer symbols than a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot may also be referred to as a PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may also be referred to as a PDSCH (PUSCH) mapping type B.

[0295] Radio frames, subframes, time slots, mini-time slots, and symbols all represent time units for transmitting signals. Radio frames, subframes, time slots, mini-time slots, and symbols may also be referred to by their respective names. In addition, time units such as frames, subframes, time slots, mini-time slots, and symbols in the present disclosure may also be interchangeable.

[0296] For example, a subframe may also be referred to as a TTI, a plurality of consecutive subframes may also be referred to as a TTI, and a time slot or a mini time slot may also be referred to as a TTI. That is, at least one of a subframe and a 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. In addition, the unit representing a TTI may also be referred to as a time slot, a mini time slot, etc. instead of a subframe.

[0297] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in the LTE system, the base station schedules each user terminal to allocate wireless resources (frequency bandwidth, transmission power, etc. that can be used in each user terminal) in TTI units. In addition, the definition of TTI is not limited to this.

[0298] TTI may also be a transmission time unit for a data packet (transport block), a code block, a code word, etc. that has been channel-coded, and may also be a processing unit for scheduling, link adaptation, etc. In addition, when TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may also be shorter than the TTI.

[0299] In addition, when one time slot or one mini time slot is referred to as TTI, one or more TTIs (i.e., one or more time slots or one or more mini time slots) may also be the minimum time unit of scheduling. In addition, the number of time slots (mini time slots) constituting the minimum time unit of scheduling may also be controlled.

[0300] A TTI having a time length of 1 ms may also be referred to as a normal TTI (TTI in 3GPP Rel.8-12), a standard TTI, a long TTI, a normal subframe, a standard subframe, a long subframe, a time slot, etc. A TTI shorter than a normal TTI may also be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a mini time slot, a sub time slot, a time slot, etc.

[0301] In addition, a long TTI (e.g., normal TTI, subframe, etc.) may be replaced by a TTI having a time length exceeding 1 ms, and a short TTI (e.g., shortened TTI, etc.) may be replaced by a TTI having a TTI length shorter than that of the long TTI and longer than 1 ms.

[0302] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may also include one or more consecutive subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in an RB may also be the same regardless of the parameter set, for example, 12. The number of subcarriers included in an RB may also be determined based on the parameter set.

[0303] In addition, an RB may also include one or more symbols in the time domain, and may also be the length of a slot, a mini-slot, a subframe, or a TTI. A TTI, a subframe, etc. may also be composed of one or more resource blocks, respectively.

[0304] In addition, one or more RBs may also be referred to as a physical resource block (Physical RB (PRB)), a sub-carrier group (Sub-Carrier Group (SCG)), a resource element group (Resource Element Group (REG)), a PRB pair, an RB pair, etc.

[0305] In addition, a resource block may also be composed of one or more resource elements (RE). For example, one RE may also be a radio resource region of one subcarrier and one symbol.

[0306] A Bandwidth Part (BWP) (also referred to as a partial bandwidth, etc.) may also represent a subset of contiguous common RBs (common resource blocks) for a parameter set in a carrier. Here, a common RB may also be identified by an index of the RB relative to a common reference point of the carrier. PRBs may also be defined in a BWP and numbered within the BWP.

[0307] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). For a UE, one or more BWPs may be configured in one carrier.

[0308] At least one of the configured BWPs may be activated, and the UE may not assume that it transmits or receives a specific signal / channel other than the activated BWP. In addition, "cell", "carrier", etc. in the present disclosure may also be replaced by "BWP".

[0309] In addition, the above-mentioned structures such as radio frames, subframes, time slots, mini-time slots and symbols are only examples. For example, the number of subframes included in a radio frame, the number of time slots in each subframe or radio frame, the number of mini-time slots included in a time slot, the number of symbols and RBs included in a time slot or mini-time slot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length can be changed in various ways.

[0310] In addition, the information, parameters, etc. described in the present disclosure may be represented by absolute values, relative values ​​relative to a specific value, or other corresponding information. For example, wireless resources may also be indicated by a specific index.

[0311] In the present disclosure, the names used for parameters, etc. are not limiting in all respects. In addition, the mathematical formulas, etc. using these parameters may be different from those explicitly disclosed in the present disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable names, and therefore, the various names assigned to these various channels and information elements are not limiting in all respects.

[0312] Information, signals, etc. described in the present disclosure may also be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be mentioned throughout the above description may also be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination thereof.

[0313] Furthermore, information, signals, etc. can be output in at least one of the following directions: from a higher layer (upper layer) to a lower layer (lower layer), and from a lower layer to a higher layer. Information, signals, etc. can also be input and output via multiple network nodes.

[0314] The input and output information, signals, etc. may be stored in a specific location (e.g., a memory), or may be managed using a management table. The input and output information, signals, etc. may be overwritten, updated, or appended. The output information, signals, etc. may also be deleted. The input information, signals, etc. may also be sent to other devices.

[0315] The notification of information is not limited to the methods / implementations described in the present disclosure, and may also be performed by other methods. For example, the notification of information in the present disclosure may also be implemented through physical layer signaling (e.g., downlink control information (Downlink Control Information (DCI)), uplink control information (Uplink Control Information (UCI))), high-layer signaling (e.g., Radio Resource Control (RRC)) signaling, broadcast information (Master Information Block (MIB)), System Information Block (SIB), etc.), Medium Access Control (MAC) signaling), other signals or a combination thereof.

[0316] In addition, physical layer signaling may also be referred to as layer 1 / layer 2 (Layer 1 / Layer 2 (L1 / L2)) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. In addition, RRC signaling may also be referred to as an RRC message, such as an RRC connection establishment (RRC Connection Setup) message, an RRC connection reconstruction (RRC Connection Reconfiguration) message, etc. In addition, MAC signaling may also be notified using, for example, a MAC control element (MACControl Element (CE)).

[0317] Furthermore, notification of specific information (eg, notification of “it is X”) is not limited to explicit notification, but may be performed implicitly (eg, by not notifying the specific information or by notifying other information).

[0318] The determination can be made by a value represented by a bit (0 or 1), by a true or false value (Boolean value) represented by true or false, or by comparison of numerical values ​​(for example, comparison with a specific value).

[0319] Whether software is called software, firmware, middle-ware, microcode, hardware description language, or other names, it should be broadly interpreted as meaning instructions, instruction sets, code, code segments, program code, program, sub-program, software modules, applications, software applications, software packages, routines, sub-routines, objects, executable files, execution threads, procedures, functions, etc.

[0320] In addition, software, instructions, information, etc. may also be sent and received via a transmission medium. For example, when software is sent from a website, server, or other remote source using at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), etc.) and wireless technology (infrared, microwave, etc.), at least one of these wired technology and wireless technology is included in the definition of transmission medium.

[0321] The terms "system" and "network" used in the present disclosure can be used interchangeably. "Network" may also refer to a device (eg, a base station) included in the network.

[0322] In the present disclosure, terms such as "precoding", "precoder", "weight (precoding weight)", "Quasi-Co-Location (QCL)", "Transmission Configuration Indication state (TCI state)", "spatial relation", "spatial domain filter", "transmission 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", and "panel" can be used interchangeably.

[0323] In the present disclosure, terms such as "Base Station (BS)", "wireless 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", and "component carrier" can be used interchangeably. There are also cases where base stations are referred to by terms such as macro cell, small cell, micro-micro cell, and micro-micro cell.

[0324] A base station can accommodate one or more (for example, three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can also provide communication services through a base station subsystem (for example, a small base station for indoor use (Remote Radio Head (RRH))). Terms such as "cell" or "sector" refer to a part or the entirety of the coverage area of ​​at least one of a base station and a base station subsystem that provides communication services within the coverage area.

[0325] In the present disclosure, terms such as “mobile station (MS)”, “user terminal”, “user device (User Equipment (UE))”, and “terminal” are used interchangeably.

[0326] In some cases, the mobile station is also referred to as a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a hand set, a user agent, a mobile client, a client, or some other appropriate terminology.

[0327] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a wireless communication device, etc. In addition, at least one of the base station and the mobile station may also be a device carried in a mobile body, a mobile body, etc. The mobile body may be a means of transportation (e.g., a vehicle, an airplane, etc.), a mobile body that moves in an unmanned manner (e.g., a drone, an autonomous driving vehicle, etc.), or a robot (manned or unmanned). In addition, at least one of the base station and the mobile station also includes a device that does not necessarily move when performing a communication operation. For example, at least one of the base station and the mobile station may also be an Internet of Things (IoT) device such as a sensor.

[0328] In addition, the base station in the present disclosure may also be replaced by a user terminal. For example, the various methods / implementations of the present disclosure may also be applied to a structure in which the communication between a base station and a user terminal is replaced by the communication between multiple user terminals (for example, it may also be referred to as device-to-device (D2D)), vehicle-to-everything (V2X), etc.). In this case, it may also be set as a structure in which the user terminal 20 has the functions possessed by the above-mentioned base station 10. In addition, expressions such as "uplink" and "downlink" may also be replaced by expressions corresponding to communication between terminals (for example, "side"). For example, an uplink channel, a downlink channel, etc. may also be replaced by a side channel.

[0329] Likewise, the user terminal in the present disclosure may be replaced by a base station. In this case, the base station 10 may have the functions of the user terminal 20 described above.

[0330] In the present disclosure, the actions are assumed to be performed by the base station, and sometimes by its upper node according to the circumstances. Obviously, in a network including one or more network nodes having a base station, various operations performed for communication with a terminal can be performed by the base station, one or more network nodes other than the base station (for example, Mobility Management Entity (MME)), Serving-Gateway (S-GW), etc., but not limited to these), or a combination thereof.

[0331] The various methods / implementations described in this disclosure may be used individually or in combination, and may be used in a switched manner as the method is executed. In addition, the processing procedures, sequences, flow charts, etc. of the various methods / implementations described in this disclosure may be reversed in order as long as they are not contradictory. For example, for the methods described in this disclosure, the elements of various steps are presented in an illustrative order, but are not limited to the specific order presented.

[0332] The various modes / implementations described in the present disclosure may also be applied to 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 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), systems using other appropriate wireless communication methods, and next-generation systems expanded based on them. In addition, multiple systems can also be applied in combination (for example, LTE or LTE-A, combination with 5G, etc.).

[0333] The term “based on” used in the present disclosure does not mean “based only on” unless otherwise specified. In other words, the term “based on” means both “based only on” and “based at least on”.

[0334] Any reference to an element using the terms "first", "second", etc. used in this disclosure does not fully define the amount or order of these elements. These terms can be used in this disclosure as a convenient method to distinguish between two or more elements. Therefore, reference to a first and a second element does not mean that only two elements can be used, or that the first element must take precedence over the second element in some form.

[0335] The term "determining" used in this disclosure may include a variety of actions. For example, "determining" may also refer to situations where judging, calculating, computing, processing, deriving, investigating, looking up (e.g., searching in a table, database or other data structure), ascertaining, etc. are considered to be "determining".

[0336] In addition, "judgment (decision)" may also be a situation where receiving (for example, receiving information), sending (for example, sending information), input (input), output (output), accessing (for example, accessing data in a memory), etc. are regarded as making a "judgment (decision)".

[0337] In addition, "judgment (decision)" can also refer to situations where resolving, selecting, choosing, establishing, comparing, etc. are considered as "judgment (decision)". In other words, "judgment (decision)" can also refer to situations where some actions are considered as "judgment (decision)".

[0338] In addition, “judgment (decision)” can also be replaced by “assuming (assuming)”, “expecting (expecting)”, “considering (considering)” and so on.

[0339] The terms "connected", "coupled", or all their variations used in this disclosure refer to all direct or indirect connections or combinations between two or more elements, and may include the situation where one or more intermediate elements exist between two elements that are "connected" or "coupled" to each other. The combination or connection between elements may be physical, logical, or a combination thereof. For example, "connection" may also be replaced by "access".

[0340] In the present disclosure, when two elements are connected, it is possible to consider being "connected" or "combined" to each other using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy with wavelengths in the wireless frequency domain, microwave region, light (both visible and invisible) region, etc. as several non-limiting and non-inclusive examples.

[0341] In the present disclosure, the term "A is different from B" may also mean "A and B are different from each other". In addition, the term may also mean "A and B are different from C, respectively". The terms "separate" and "combined" may also be interpreted in the same way as "different".

[0342] When the terms "include", "including", and variations thereof are used in the present disclosure, these terms have an inclusive meaning similar to the term "comprising". Furthermore, the term "or" used in the present disclosure does not have an exclusive OR meaning.

[0343] In the present disclosure, when an article is added by translation like a, an, and the in English, for example, the present disclosure may also include a case where the noun following the article is in plural form.

[0344] The invention involved in the present disclosure has been described in detail above, but it is obvious to those skilled in the art that the invention involved in the present disclosure is not limited to the embodiments described in the present disclosure. The invention involved in the present disclosure can be implemented as a modified and altered mode without departing from the gist and scope of the invention determined based on the description of the claims. Therefore, the description of the present disclosure is for the purpose of illustrative description and does not have any limiting meaning on the invention involved in the present disclosure.

Claims

1. A terminal having: a receiving unit, receiving a configuration for a physical uplink control channel PUCCH corresponding to a multicast physical downlink shared channel PDSCH, downlink control information DCI for scheduling the PDSCH, and the PDSCH, wherein the configuration is sent using radio resource control RRC signaling; and a control unit, determining a PUCCH resource for a hybrid automatic repeat request acknowledgment 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 transmitting the DCI, The DCI is common among multiple terminals. The PUCCH format for the PUCCH resource is a PUCCH format not accompanied by a demodulation reference signal.

2. The terminal according to claim 1, wherein: The receiving unit monitors the DCI in a common search space for multicast.

3. The terminal according to claim 1, wherein: The cyclic redundancy check CRC of the DCI is scrambled by a group common radio network temporary identifier RNTI.

4. A wireless communication method of a terminal, comprising: A step of receiving a configuration for a physical uplink control channel PUCCH corresponding to a multicast physical downlink shared channel PDSCH, downlink control information DCI for scheduling the PDSCH, and the PDSCH, wherein the configuration is sent using radio resource control RRC signaling; and A step of determining a PUCCH resource for a hybrid automatic repeat request acknowledgment 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 transmitting the DCI, The DCI is common among multiple terminals. The PUCCH format for the PUCCH resource is a PUCCH format not accompanied by a demodulation reference signal.

5. A base station, comprising: a transmitting unit, which transmits a configuration for a physical uplink control channel PUCCH corresponding to a multicast physical downlink shared channel PDSCH, downlink control information DCI for scheduling the PDSCH, and the PDSCH, wherein the configuration is transmitted using radio resource control RRC signaling; and a control unit, which indicates a PUCCH resource for a hybrid automatic repeat request confirmation 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 transmitting the DCI, The DCI is common among multiple terminals. The PUCCH format for the PUCCH resource is a PUCCH format not accompanied by a demodulation reference signal.

6. A system having a base station and a terminal, The base station has: a transmitting unit, which transmits a configuration for a physical uplink control channel PUCCH corresponding to a multicast physical downlink shared channel PDSCH, downlink control information DCI for scheduling the PDSCH, and the PDSCH, wherein the configuration is transmitted using radio resource control RRC signaling; and a control unit, which indicates a PUCCH resource for a hybrid automatic repeat request confirmation 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 transmitting the DCI, The terminal has: A receiving unit, receiving the setting, the DCI and the PDSCH; and a control unit, which determines the PUCCH resource based on the setting, the PUCCH resource indicator field, and the CCE index, The DCI is common among multiple terminals. The PUCCH format for the PUCCH resource is a PUCCH format not accompanied by a demodulation reference signal.

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