Terminal, base station, system, and wireless communication method

Abstract

Appropriate control is provided for retransmission control of at least one of broadcast and multicast transmissions. The user terminal includes: a receiving unit for receiving specific information transmitted via at least one of broadcast and multicast; and a control unit for determining the transmission power of the uplink channel used in transmitting retransmission control information for the specific information, based on transmission power parameters notified to each user terminal separately.

Description

Technical Field

[0001] This disclosure relates to user terminals and wireless communication methods in next-generation mobile communication systems. Background Technology

[0002] In Universal Mobile Telecommunications System (UMTS) networks, Long Term Evolution (LTE) was standardized with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). Furthermore, LTE-Advanced (3GPP Rel. 10-14) was standardized with the aim of further increasing capacity and improving the height of LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

[0003] The development of successor systems to LTE is also underway (e.g., also known as the 5th generation mobile communication system (5G), 5G+ (plus), New Radio (NR), 3GPP e1.15 and later, etc.).

[0004] Existing technical documents

[0005] Non-patent literature

[0006] Non-patent document 1: 3GPP TS 36.300V8.12.0 “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] The problem that the invention aims to solve

[0008] Envision that in future wireless communication systems (e.g., NR), as a data transmission method, unicast transmission, which transmits data individually to each user terminal (UE), broadcast transmission, and multicast transmission, which transmit data to multiple UEs in a common manner, will be supported.

[0009] Furthermore, research is underway to support retransmission control (e.g., HARQ) for at least one of broadcast and multicast transmissions in NR. However, how to control retransmission for broadcast or multicast transmissions has not been fully studied.

[0010] Therefore, one of the objectives of this disclosure is to provide a user terminal and a wireless communication method that can appropriately control retransmission control for at least one of broadcast transmission and multicast transmission.

[0011] Methods for solving problems

[0012] A user terminal according to one aspect of this disclosure is characterized by comprising: a receiving unit for receiving specific information transmitted via at least one of broadcasting and multicasting; and a control unit for determining the transmission power of the uplink channel used in transmitting retransmission control information for the specific information based on transmission power parameters notified to each user terminal respectively.

[0013] The effects of the invention

[0014] According to one aspect of this disclosure, retransmission control for at least one of broadcast and multicast transmissions can be appropriately controlled. Attached Figure Description

[0015] Figure 1 This is a diagram illustrating an example of broadcast / multicast transmission.

[0016] Figure 2 This is a diagram illustrating an example of retransmission control involved in the first approach.

[0017] Figure 3 This is a diagram illustrating another example of retransmission control involved in the first approach.

[0018] Figure 4 This is a diagram illustrating an example of retransmission control involved in the second approach.

[0019] Figure 5 This is a diagram illustrating an example of retransmission control involved in the third approach.

[0020] Figure 6 This is a diagram illustrating an example of retransmission control involved in the fourth approach.

[0021] Figure 7 This is a diagram illustrating another example of retransmission control involved in the fourth approach.

[0022] Figure 8 This is a diagram illustrating an example of a schematic structure of a wireless communication system according to one embodiment.

[0023] Figure 9 This is a diagram illustrating an example of the structure of a base station according to one embodiment.

[0024] Figure 10 This is a diagram illustrating an example of the structure of a user terminal according to one embodiment.

[0025] Figure 11 This is a diagram illustrating an example of the hardware structure of a base station and a user terminal according to one embodiment. Detailed Implementation

[0026] Envisioning future wireless communication systems (e.g., NR) supporting unicast transmission, broadcast transmission, and multicast transmission. In unicast transmission, data or channels can be transmitted individually (e.g., UE-specific) to each UE. At least one of broadcast and multicast transmission (hereinafter also referred to as broadcast / multicast transmission) can transmit data or channels publicly to multiple UEs (e.g., a group of UEs).

[0027] Unicast, broadcast, and multicast transmissions can each use different channels (at least one of logical and physical channels). Alternatively, broadcast and multicast transmissions can use the same structure.

[0028] Broadcast / multicast transmission becomes an effective transmission method when distributing the same information to multiple UEs (e.g., a specific group of UEs). Therefore, broadcast / multicast transmission is envisioned for notifying public safety and intelligent transport systems (ITS) information, such as the distribution of road conditions, traffic signs, and traffic lights. Alternatively, broadcast / multicast transmission is envisioned for informing audiences at concerts or stadiums.

[0029] In NR, retransmission control for broadcast / multicast transmissions (e.g., HARQ operation) can also be considered. However, how to control retransmission for broadcast / multicast transmissions has not been fully studied. Without proper retransmission control, communication quality may deteriorate.

[0030] The inventors studied retransmission control for broadcast / multicast transmissions and completed this invention.

[0031] In the following description, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Each aspect of the embodiments may be applied individually or in combination. In the following description, HARQ-based re-transmission will be used as an example of retransmission control, but the present invention is not limited thereto.

[0032] In the following description, retransmission control for broadcast transmissions can be renamed as retransmission control for information transmitted via broadcast. Information transmitted via broadcast can also be renamed as data, data channel, DL-SCH, broadcast channel, control information, DCI, control channel, and at least one of broadcast control information. Similarly, retransmission control for multicast transmissions can be renamed as retransmission control for information transmitted via multicast. Information transmitted via multicast can also be renamed as data, data channel, DL-SCH, multicast channel, control information, DCI, control channel, and multicast control information.

[0033] Information transmitted via broadcast / multicast can be included in data scheduled via downlink control information (e.g., DCI) (e.g., DL-SCH, shared channel, etc.), or it can be transmitted via higher-layer signaling (e.g., at least one of RRC signaling and broadcast information), or it can be transmitted via dedicated signals or channels. When information transmitted via broadcast / multicast is included in data, the DCI scheduling that data can also apply broadcast / multicast transmission. In the following description, transmission via DCI or higher-layer signaling can also be described as applying at least one of unicast transmission (or UE-specific transmission) and broadcast / multicast transmission (or UE-common transmission).

[0034] (First method)

[0035] The first approach describes retransmission control for broadcast / multicast transmissions.

[0036] Figure 1 This illustration shows an example of a base station sending specific information to multiple UEs (e.g., UE groups) using at least one of broadcast and multicast (hereinafter also referred to as broadcast / multicast). Here, it is shown that the base station broadcasts / multicasts to UE group #1 and UE group #2 respectively. Furthermore, the number of UE groups, the UEs constituting the UE groups, etc., can be appropriately changed and applied.

[0037] Each UE can determine, based on specific information, whether to support retransmission control for information transmitted via broadcast / multicast (or whether to apply retransmission control or whether to set retransmission control) (see [reference]). Figure 2The specific information may be information communicated using at least one of higher-layer signaling (option 1) and downlink control information (option 2) notified from the network (e.g., a base station). Alternatively, the UE may determine whether to apply retransmission control based on specific rules (option 3).

[0038] <Option 1>

[0039] The UE can decide whether to apply retransmission control for information transmitted via broadcast / multicast based on higher-layer signaling. The base station can use higher-layer signaling to notify whether to apply retransmission control on a per-UE basis, or on a per-UE group basis.

[0040] When broadcast transmission (e.g., transmission using a broadcast channel) and multicast transmission (e.g., transmission using a multicast channel) are supported respectively, it is possible to separately configure whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission. This allows for flexible control over whether to apply retransmission control.

[0041] Alternatively, if both broadcast and multicast transmission are supported, it is possible to publicly configure whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission. In this case, if retransmission control is configured for one of broadcast and multicast transmissions, the UE can also apply that configuration to the other. As a result, the configuration of retransmission control can be simplified.

[0042] <Option 2>

[0043] The UE can also determine whether to apply retransmission control for information transmitted via broadcast / multicast based on downlink control information (e.g., DCI). The base station can use a UE-specific DCI to notify each UE whether to apply retransmission control, or it can use a group-wide DCI to notify each UE group whether to apply retransmission control. For example, in cases where information transmitted via broadcast / multicast is scheduled by a DCI, information about HARQ-ACK (e.g., whether to apply, transmission timing, and at least one resource) can be included in that DCI.

[0044] When broadcast and multicast transmissions are supported separately, it is also possible to configure whether to apply retransmission control for broadcast transmissions and whether to apply retransmission control for multicast transmissions separately. This allows for flexible control over whether to apply retransmission control.

[0045] Alternatively, if both broadcast and multicast transmission are supported, it is also possible to publicly configure whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission. In this case, if retransmission control is configured for one of broadcast and multicast transmissions, the UE can also apply the same setting to the other. This simplifies the configuration of retransmission control.

[0046] <Option 3>

[0047] The UE can also implicitly decide whether to apply retransmission control for information transmitted via broadcast / multicast based on specific rules. These specific rules can also be specific conditions set by transmission or reception (e.g., transmission conditions used in broadcast / multicast transmission). The following describes the case where the specific conditions are repeated transmission (Case 1) and at least one of modulation and coding scheme (MCS) and coding rate (Case 2). The specific conditions are not limited to these.

[0048] [Scenario 1]

[0049] When repetition is applied to information transmitted via broadcast / multicast, the UE may determine that retransmission control (e.g., HARQ) is not supported or that retransmission control is not applied. Conversely, the UE may determine that retransmission control is supported or is applied even if repetition is not applied.

[0050] The UE can also decide whether to apply retransmission control based on the number of repeated transmissions (also known as the repetition factor). For example, if the number of repeated transmissions is above a certain value (e.g., X), the UE may not apply retransmission control, while in other cases (e.g., if the number of transmissions is less than the certain value), the UE may apply retransmission control. The specific value (e.g., X) can be predefined in the specification or can be notified to the UE from the base station via higher-layer signaling.

[0051] Whether to apply retransmission (or the number of retransmissions) can also be set for each UE group. Alternatively, retransmission (or the number of retransmissions) can be set for each UE. In the case of setting it for each UE, retransmission control can also be set independently for each UE included in the UE group.

[0052] [Scenario 2]

[0053] The UE can also determine whether to apply retransmission control for information transmitted via broadcast / multicast based on at least one of the MCS and coding rate applied to the information transmitted via broadcast / multicast (hereinafter also referred to as MCS / coding rate).

[0054] For example, the UE may also not apply retransmission control when the MCS / coding rate corresponding to the information transmitted via broadcast / multicast is below a specific value (e.g., Y), and apply retransmission control otherwise (e.g., when the MCS / coding rate is greater than the specific value). The specific value (e.g., Y) can be predefined in the specification or can also be notified to the UE from the base station via higher layer signaling or the like.

[0055] In this way, by controlling whether to apply retransmission control for broadcast / multicast transmission based on specific conditions, it is possible to flexibly control retransmission control based on the communication environment or communication conditions.

[0056] <HARQ process>

[0057] In HARQ-based retransmission control, retransmission control of data (transport block (TB) or code block (CB)) is performed in units of processes (HARQ processes). In HARQ processes with the same number (HARQ process number (HPN)), the same data is retransmitted until an ACK is received. The HARQ process number is also referred to as the HARQ process ID (HARQ process identifier).

[0058] In one time interval (e.g., a time slot or a subframe), one HARQ process can be used, or multiple HARQ processes can be used. By independently and parallelly processing multiple HARQ processes, it is possible to transmit data of the next HARQ process without waiting for the A / N of the previous HARQ process, thereby reducing the latency time.

[0059] Retransmission control can also be performed based on HARQ processes in retransmission control for broadcast / multicast transmission. For example, X (or X number, X) (X≧1) HARQ processes can be set for the information transmitted via broadcast / multicast. X can be predefined in the specification or can also be notified to the UE from the base station via at least one of higher layer signaling and downlink control information.

[0060] In the case of separately supporting broadcast transmission and multicast transmission, X for broadcast transmission and X for multicast transmission can also be set separately. X for broadcast transmission and X for multicast transmission can also be set commonly. Or, different X can be set for each broadcast transmission (or each multicast transmission).

[0061] In addition, it is possible to consider the UE sending HARQ-ACK for unicast transmissions and HARQ-ACK for broadcast / multicast transmissions (see [link]). Figure 3 ). Figure 3 An example of a UE reporting HARQ-ACK#B for broadcast / multicast transmission and HARQ-ACK#A for unicast transmission is shown.

[0062] In this case, it is also possible to separate the HARQ process pool corresponding to information sent via unicast and the HARQ process pool corresponding to information sent via broadcast / multicast. The HARQ process pool can be the processing operation of HARQ processes, or it can be the value of HARQ process number or a range of HARQ process numbers.

[0063] For example, the HARQ process number used for unicast transmission (e.g., HARQ-ACK#B) and the HARQ process number used for broadcast / multicast transmission (e.g., HARQ-ACK#A) can also be set separately. The UE can also control the retransmission of unicast transmission based on the HARQ process number used for unicast transmission, and control the retransmission of broadcast / multicast transmission based on the HARQ process number used for broadcast / multicast transmission.

[0064] Thus, by setting up separate HARQ process pools for information sent via unicast and information sent via broadcast / multicast, conflicts between HARQ processes sent via unicast and those sent via broadcast / multicast can be avoided.

[0065] Alternatively, you can share the HARQ process pool corresponding to messages sent via unicast and the HARQ process pool corresponding to messages sent via broadcast / multicast.

[0066] In this case, a common HARQ process number (e.g., X HARQ processes) can also be applied to both the HARQ process used for unicast transmission and the HARQ process used for broadcast / multicast transmission.

[0067] The network (e.g., a base station) can also control HARQ process processing to prevent conflicts between information sent via unicast and information sent via broadcast / multicast. For example, at least one of the base station and the UE can also control the process to prevent the HARQ process number assigned to one of unicast and broadcast / multicast transmissions from being assigned to the other.

[0068] Alternatively, priorities can be set for HARQ processes (e.g., a priority rule), and retransmission control can be performed based on this priority in the event of a duplicate HARQ process. For example, broadcast / multicast transmissions can have a higher priority than unicast transmissions. In the event of a conflict between a HARQ process corresponding to a unicast transmission and a HARQ process corresponding to a broadcast / multicast transmission, the UE can prioritize retransmission control for the HARQ process corresponding to the broadcast / multicast transmission.

[0069] The priority of HARQ processes can also be set based on other conditions. For example, the priority of HARQ processes can be determined based on the service (or business type). As an example, the priority of the HARQ process corresponding to the first business type (e.g., URLLC) can be set higher than the priority of the HARQ process corresponding to the second business type (e.g., eMBB).

[0070] Additionally, when the HARQ process number is 1 (X = 1), the information specifying the HARQ process number may not be included in the scheduling information. For example, when X = 1, the field used for HARQ process notification may be omitted from the DCI of at least one of the control information and data sent via multicast / broadcast, or it may be used for other purposes. In other cases (X > 1), an n-bit field (e.g., n = log2(X)) may be set in the DCI to notify the HARQ process ID corresponding to the multicast / broadcast transmission.

[0071] <Soft Buffer>

[0072] The UE may also have a buffer (soft buffer) to temporarily store received data that failed to decode. Received data (e.g., TB, code block, or code block group (CBG) containing more than one code block) may also be stored for each HPN in the soft buffer.

[0073] In addition, the UE can also perform soft combining of received data (or retransmitted data) based on the same repeatedly transmitted HPN. Furthermore, the user terminal can also perform soft combining of data stored in the soft buffer with received data from the same HPN. Soft combining refers to assigning the same HPN to multiple data generated from the same information bit string and transmitting them, with the receiver combining the multiple data from the same HPN.

[0074] Alternatively, the soft buffers on the UE side for information sent via unicast and on the UE side for information sent via broadcast / multicast can be configured sharedly. In this case, the soft buffers can be used effectively even if decoding of one of the transmissions fails consecutively.

[0075] Alternatively, it is possible to separately set the soft buffer on the UE side for information sent via unicast and the soft buffer on the UE side for information sent via broadcast / multicast. For example, in the UE, it is also possible to set a soft buffer for broadcast / multicast transmission in addition to the soft buffer used in unicast transmission. Thereby, it is possible to prevent the decoding failure of one transmission from affecting the soft buffer of the other transmission.

[0076] (Second method)

[0077] The second method describes the feedback control of the delivery confirmation signal (or also referred to as the retransmission control signal, HARQ-ACK) for broadcast / multicast transmission.

[0078] <HARQ-ACK transmission timing>

[0079] The UE feeds back the HARQ-ACK for information sent via broadcast / multicast at a specific timing (e.g., K1) (see Figure 4 ). In Figure 4 , it shows that the UE included in UE group #1 feeds back the HARQ-ACK at a specific timing (e.g., K 11 , K 12 ), and the UE included in UE group #2 feeds back the HARQ-ACK at a specific timing (e.g., K 21 , K 22 ).

[0080] The specific timing can be defined by a fixed value or can also be notified from the network (e.g., the base station). For example, the UE can also apply any one of the following options 2-1 to 2-3 to determine the transmission timing of the HARQ-ACK.

[0081] [Option 2-1]

[0082] One timing value can be applied as the transmission timing of the HARQ-ACK for broadcast / multicast transmission. This one timing value can be defined in the specification or can also be notified from the base station to the UE via high-layer signaling, etc. The UE can also determine the transmission timing of the HARQ-ACK for broadcast / multicast transmission based on this one timing value (e.g., the fixed value K1).

[0083] For example, in Figure 4 , it can also be that K 11 = K 12 = K 21 = K 22 = fixed value K1. Alternatively, one timing value can be set for each UE group. For example, in Figure 4 , it can be that K 11 = K12 = Fixed value K A K 21 =K 22 = Fixed value K B .

[0084] The HARQ-ACK feedback timing can also be set publicly (e.g., the same value) for multiple UEs included in a predetermined UE group that receive information transmitted via broadcast / multicast. For example, in Figure 4 In, it can also be at least K. 11 =K 12 K 21 =K 22 This allows for the alignment of HARQ-ACK feedback timings from multiple UEs included in a predetermined UE group.

[0085] Alternatively, the HARQ-ACK feedback timing can be set independently for each of the multiple UEs included in the UE group (e.g., with different values). For example, in Figure 4 In, it can also be at least K. 11 ≠K 12 K 21 ≠K 22 In this scenario, the feedback timing of HARQ-ACK from multiple UEs contained in a specific UE group can be distributed. Alternatively, the same value can be set for a portion of the multiple UEs contained in a specific group, and different values ​​can be set for the other UEs.

[0086] [Option 2-2]

[0087] Alternatively, the structure can be configured as follows: a set of transmission timing values ​​for HARQ-ACK broadcast / multicast transmissions is defined (or, also known as a combination of transmission timing values, multiple transmission timing candidates, or a set of transmission timing candidates), and a specific transmission timing value is selected from the set. The set of HARQ-ACK transmission timing values ​​can also be predefined in the specification, or it can be notified to the UE from the base station using higher-layer signaling, etc.

[0088] Furthermore, the base station can also send information to the UE to specify a particular transmission timing value from the set of HARQ-ACK transmission timing values. For example, the base station can also include information specifying a particular transmission timing value in the downlink control information and send it to the UE. The UE can also determine the HARQ-ACK transmission timing value based on the bit information included in the downlink control information.

[0089] Downlink control information (e.g., group common PDCCH) can also be sent to multiple UEs (e.g., UEs included in a specific group). In this case, all UEs included in a specific group can use the same timing to feedback HARQ-ACK.

[0090] [Option 2-3]

[0091] The base station can also set a first transmission timing parameter (e.g., offset (e.g., T_delta or ΔT)) of the HARQ-ACK transmission timing for each UE. For example, the base station can also use higher layer signaling, etc. to set the offset of the HARQ-ACK transmission timing to the UE. In this case, the offset can be set separately for each UE (e.g., different offsets), or the offset can be set for each group (e.g., an offset common to a specific group).

[0092] Furthermore, the base station can also use downlink control information, etc. to notify the UE of information about the second transmission timing parameter (e.g., the transmission timing of HARQ-ACK). For example, the base station can use DCI (or PDCCH) for scheduling broadcast / multicast transmission or group common DCI (or, group common PDCCH) to notify multiple UEs of the same transmission timing (e.g., K1). Or, the base station can use UE-specific DCI (or UE-specific PDCCH) to separately notify each UE of the transmission timing.

[0093] Each UE determines the HARQ-ACK transmission timing (e.g., K1 + T_delta) based on the first transmission timing parameter (e.g., T_delta) notified by higher layer signaling and the second transmission timing parameter (e.g., transmission timing K1) notified by DCI. Thus, by specifically notifying at least one of the first parameter and the second parameter (e.g., the offset) to the UE, even when the other is set to be UE group common, the transmission timing can be flexibly controlled among UEs.

[0094] In addition, the HARQ-ACK transmission timing for unicast transmission and the HARQ-ACK transmission timing for broadcast / multicast transmission can be set separately (e.g., by using different methods). Thus, the HARQ-ACK feedback timing can be flexibly controlled according to each transmission.

[0095] <HARQ-ACK Feedback Resource>

[0096] The UE can also determine, based on specific information, at least one of the resources and formats (hereinafter also referred to as resources / formats) used in the feedback of HARQ-ACK for broadcast / multicast transmission. For example, the UE can also apply any of the following options 3-1 to 3-3 to determine the resources / format for HARQ-ACK. In addition, the timing of HARQ-ACK transmission can apply any of the above options 2-1 to 2-3.

[0097] [Option 3-1]

[0098] The base station can also use higher-layer signaling to notify each UE of the resource / format of a specific channel (e.g., PUCCH) used in HARQ-ACK transmission. Alternatively, the resource / format of the PUCCH notified to each UE can be configured separately (e.g., different resource / formats can be set).

[0099] Alternatively, the base station can use higher-layer signaling to notify each UE group of information regarding the PUCCH resources / format used in HARQ-ACK transmission. That is, the PUCCH resources / format can also be configured on a UE group basis. In this case, UEs included in the same group can also use the same resources / format for HARQ-ACK transmission.

[0100] In option 3-1, the UE can determine the resources / format to be used in HARQ-ACK transmission based on information notified via higher-layer signaling (without utilizing L1 signaling).

[0101] [Option 3-2]

[0102] The base station can also use higher-layer signaling to notify each UE of the parameters of the first resource / format. The parameters of the first resource / format can also be information related to the resource index (e.g., PUCCH_index) of a specific channel (e.g., PUCCH) used in HARQ-ACK transmission. The resource index of the PUCCH can be set separately for each UE (e.g., different resource indices).

[0103] Furthermore, the base station can also assign multiple sets of PUCCH resources (also known as multiple PUCCH resource candidate sets) to the UE via higher-layer signaling. Further, the base station can also include information for specifying a particular set from the multiple sets in the downlink control information and send it to the UE. The specific set can also be referred to as a second resource / format parameter.

[0104] For example, the base station can also use DCI (or PDCCH) for scheduling broadcast / multicast transmissions, or group-common DCI (or group-common PDCCH) to notify multiple UEs of a specific set. Alternatively, the base station can use UE-specific DCI (or UE-specific PDCCH) to separately notify each UE of a specific set.

[0105] Each UE can also determine the PUCCH resource / format based on the parameters of the first resource / format notified via higher-layer signaling and the parameters of the second resource / format specified using at least one of DCI and higher-layer signaling. For example, the UE determines the PUCCH resource / format from a set of specific PUCCH resources specified by downlink control information based on the PUCCH resource index notified via higher-layer signaling.

[0106] By specifically notifying at least one of the first resource / format parameters and the second resource / format parameters (e.g., the PUCCH resource index) to the UE, different PUCCH resources can be used among UEs even when the other is set to be UE group-common.

[0107] [Option 3-3]

[0108] The base station can also set multiple PUCCH resources (also referred to as PUCCH resource candidates) for the UE via higher-layer signaling. Further, the base station can send downlink control information containing information for specifying a specific PUCCH resource from among the multiple PUCCH resources to the UE (e.g., multiple UEs included in a specific group). The downlink control information can also be DCI sent via group-common PDCCH, or can also be DCI for scheduling broadcast / multicast transmissions.

[0109] In this case, the same PUCCH resource can also be specified for multiple UEs included in a specific group.

[0110] (Third method)

[0111] The third method describes the transmission power control of the uplink channel (e.g., at least one of PUCCH and PUSCH) used in the transmission of HARQ-ACK for broadcast / multicast transmissions. In the following description, PUCCH is exemplified as the uplink channel used in the transmission of HARQ-ACK, but the same can be similarly applied to other uplink channels (e.g., PUSCH).

[0112] <Transmission power control of UL>

[0113] In Rel.15, the UE performs transmission power control (TPC) for each transmission opportunity i. Transmission opportunity i can also be a PUSCH, PUCCH, SRS, or PRACH transmission opportunity. Transmission opportunity i can also be determined by a slot index n for subcarrier spacing configuration μ within a frame with a system frame number (SFN). s,f μ The first symbol in the time slot (index of the first symbol of transmission opportunity i) S and the number of consecutive symbols L are defined.

[0114] The transmission power of the PUCCH is controlled based on the TPC command (value, increment / decrement value, correction value, indication value, etc.) represented by the value of a specific field (also known as the TPC command field, first field, etc.) within the DCI.

[0115] For example, regarding the transmission occasion (also known as the transmission period, etc.) i of the PUCCH for carrier f of cell c using the power control adjustment state, the transmission power (P) is... PUCCH,b,f,c (I,q u ,q d ,I)) can also be represented by the following formula (1).

[0116] Here, the power control adjustment state can be set to have multiple states (e.g., two states) or a single state via higher-level parameters. Furthermore, when multiple power control adjustment states are set, one of these states can be identified by an index I (e.g., I ∈ {0, 1}). The power control adjustment state can also be referred to as the PUCCH power control adjustment state, the first state, the second state, etc.

[0117] Furthermore, the PUCCH transmission opportunity i is a specific period for transmitting the PUCCH, and can also be composed of, for example, more than one symbol or more than one time slot.

[0118] [Number 1]

[0119] Equation (1)

[0120]

[0121] In equation (1), P CMAX,f,c (i) For example, the transmit power (also known as maximum transmit power, etc.) of the user terminal on carrier f of cell c in transmission opportunity i. O_PUCCH,b,f,c (q u For example, it is a parameter related to the target received power of the BWP b of the carrier f of cell c in transmission opportunity i (e.g., also referred to as a parameter related to transmit power offset, transmit power offset PO, or target received power parameter, etc.).

[0122] M PUCCH RB,b,f,c (i) For example, the number of resource blocks (bandwidth) allocated to the PUCCH for transmission opportunity i in the uplink BWP b of cell c and subcarrier spacing μ of carrier f. b,f,c (q d For example, the index q is the reference signal used by the user terminal to associate the uplink BWP with the carrier f of cell c. d Calculated path loss.

[0123] Δ F_PUCCH (F) are high-level parameters assigned to each PUCCH format. Δ TF,b,f,c (i) is the transmission power adjustment component (offset) of the uplink BWP b for carrier f in cell c.

[0124] g b,f,c (i, I) is the value of the TPC command (e.g., power control adjustment state, accumulated value of TPC command) based on the uplink BWP of the carrier f of cell c and transmission opportunity i. For example, the accumulated value of TPC command can also be represented by a specific formula.

[0125] TPC commands can also be determined based on the values ​​of specific fields (also known as TPC command fields, first fields, etc.) within the DCI used for scheduling PUSCH or PDSCH. Power control information can also be referred to as TPC commands (also known as values, increment / decrease values, correction values, etc.).

[0126] Furthermore, Equation (1) is merely illustrative and not a limitation. The user terminal only needs to control the transmission power of the PUCCH based on at least one parameter illustrative in Equation (1), which may include additional parameters or omit some parameters. Moreover, in Equation (1) above, the transmission power of the PUCCH is controlled for each BWP of a certain carrier in a certain cell, but it is not limited to this. At least some of the cell, carrier, BWP, and power control adjustment state may also be omitted.

[0127] The UE applies a specific transmit power (or a specific transmit power parameter) to the PUCCH used in the feedback of HARQ-ACK for broadcast / multicast transmissions (see [link]). Figure 5 ).exist Figure 5 The image shows UEs included in UE group #1 applying a specific transmit power (e.g., P). 11 P 12 The PUCCH feedback HARQ-ACK of UEs in UE group #2 is achieved by applying a specific transmit power (e.g., P). 21 P 22 The PUCCH feedback indicates the HARQ-ACK status.

[0128] The UE can also determine a specific transmit power based on specific information. For example, the UE can also apply any of the following options 4-1 to 4-2 to determine the transmit power.

[0129] [Option 4-1]

[0130] The UE can also determine the PUCCH transmission power based on parameters set via higher-layer signaling (also known as transmission power parameters). The parameters set via higher-layer signaling can be parameters included in the above equation (1) (e.g., a combination of P0 and α), or other parameters.

[0131] Furthermore, the transmission power parameters can be set separately (e.g., different transmission power parameters) among multiple UEs within a specific group of UEs that are transmitting the same information via broadcast / multicast. That is, the transmission power parameters can also be set separately for each UE. For example, in... Figure 5 In the middle, P is set separately. 11 and P 12 (or, P) 21 and P 22 ).

[0132] Furthermore, the transmit power value can be set separately for multiple UEs within a specific UE group that are transmitting the same information via broadcast / multicast. This allows for flexible control of transmit power, taking into account interference between different UEs.

[0133] [Option 4-2]

[0134] The base station can also use higher-layer signaling to set a first transmit power parameter for each UE. The first transmit power parameter can be set commonly for multiple UEs (e.g., a group of UEs) or separately for each UE (e.g., with different values). The first transmit power parameter can be, for example, a power offset (e.g., P_delta or P...). Δ ).

[0135] In addition, the base station can also notify the UE of a second transmit power parameter using at least one of higher-layer signaling and DCI. The second parameter can also be a power control value (e.g., P_M or P...). M For example, the base station may also use higher-layer signaling to set a set of second transmit power parameters (e.g., multiple candidate values ​​or sets of second parameters) to the UE, and use DCI to notify the UE of specific second parameters.

[0136] For example, a base station may use a DCI (or PDCCH) sent via scheduled broadcast / multicast, or a group common DCI (or group common PDCCH), to notify multiple UEs of a specific second parameter. Alternatively, the base station may use a UE-specific DCI (or UE-specific PDCCH) to notify each UE of a specific second parameter separately.

[0137] Each UE can also adjust the PUCCH transmission power based on a first transmission power parameter notified via higher-layer signaling and a second transmission power parameter (e.g., P_delta+P_M) specified using at least one of DCI and higher-layer signaling.

[0138] By specifically informing the UE of at least one of the first and second transmit power parameters (e.g., P_delta), different transmit power can be utilized among the UEs even if the other is set to be common to the UE group.

[0139] [Option 4-3]

[0140] Each UE can also adjust the PUCCH transmission power based on TPC commands. For example, in addition to options 4-1 or 4-2, the UE can also consider TPC commands to determine the PUCCH transmission power.

[0141] TPC commands can also be included in DCIs that schedule broadcast / multicast transmissions. Alternatively, TPC commands can be included in other DCIs that are different from those that schedule broadcast / multicast transmissions. The DCI that sends TPC commands can also be sent as a UE-specific DCI or as a DCI common to a specific UE group (e.g., a group common PDCCH).

[0142] (Fourth method)

[0143] The fourth section describes the transmission control for HARQ-ACK for broadcast / multicast transmissions.

[0144] In HARQ-based retransmission control, the UE sends an ACK if data reception and processing (e.g., decoding) is successful, and sends a NACK if it fails. For retransmission control of information transmitted via broadcast / multicast, the UE may also apply any of the following options 5-1 to 5-2.

[0145] [Option 5-1]

[0146] The UE can also be controlled to report only one of the HARQ-ACK responses for broadcast / multicast transmissions (e.g., NACK). For example, the UE can also be controlled to report NACK if decoding of information transmitted via broadcast / multicast fails, and not report ACK if decoding succeeds (see [link to relevant documentation]). Figure 6 ).

[0147] exist Figure 6 The diagram illustrates the scenarios where UEs in UE group #1 send a NACK when decoding information sent via broadcast / multicast fails, and UEs in UE group #2 send a NACK when decoding information sent via broadcast / multicast fails. Alternatively, it can be controlled so that no ACK is sent when decoding is successful.

[0148] The base station can also determine that data reception was successful for a UE that did not report a NACK. NACK detection in the base station can also be based on power detection (also known as energy detection). For example, the base station can also use the same mechanism as the detection of scheduling requests (SRs) sent via PUCCH to perform NACK detection.

[0149] Furthermore, the resources for NACK reports from each UE can be shared among multiple UEs. That is, UEs sending NACKs for broadcast / multicast transmissions can also utilize the same UL channel resources (e.g., PUCCH resources) to send NACKs. The resources used for this NACK report can also be defined in the specification and can be notified to each UE (or group of UEs) from the base station using at least one of downlink control information and higher-layer signaling.

[0150] For example, in Figure 6In the case where multiple UEs in UE group #1 send NACK, they can also use the same UL channel resources (e.g., resources with the same time and frequency domains) to send NACK. Similarly, in the case where multiple UEs in UE group #2 send NACK, they can also use the same UL channel resources (e.g., resources with the same time and frequency domains) to send NACK.

[0151] In this way, by publicly configuring resources for NACK reporting for multiple UEs (e.g., the same UE group), resource utilization efficiency can be improved.

[0152] The base station can also perform retransmission control (e.g., determine whether to retransmit) based on whether a NACK report is detected in the resources used for NACK. For example, suppose the base station detects a NACK in the resources allocated to UE group #1. This means that at least one UE in UE group #1 (UEs that sent via broadcast / multicast) failed to decode.

[0153] In this scenario, the base station can also retransmit information (e.g., transport blocks) via broadcast / multicast. The UE can also control whether to receive the retransmitted information based on its own reception status. For example, control can be implemented so that UEs that have reported NACK receive the retransmitted information. On the other hand, UEs that have not reported NACK (e.g., UEs that have successfully decoded) can skip the reception processing (e.g., decoding) of the retransmitted information.

[0154] In this way, by controlling whether to receive retransmitted information based on the reception status, the increased burden on the UE's reception processing can be suppressed.

[0155] Additionally, the above description illustrates the case where only NACK is reported, but it is not limited to this. It can also be configured to only send ACK.

[0156] [Option 5-2]

[0157] The UE can control itself to report only at least one of ACK and NACK as a HARQ-ACK for broadcast / multicast transmissions. For example, the UE can also control itself to report NACK if decoding of information transmitted via broadcast / multicast fails, and report ACK if decoding succeeds. Alternatively, the UE can control itself to report NACK if decoding fails, as in option 5-1 above, and not report ACK if decoding succeeds.

[0158] The resources used by each UE in reporting at least one of ACK and NACK (hereinafter also referred to as ACK / NACK) can be configured separately for each UE (e.g., UE-specific) (see See Figure 7 ).exist Figure 7 The diagram illustrates the following scenario: UEs in UE group #1 use different resources to send ACK / NACK messages for broadcast / multicast, while UEs in UE group #2 use different resources to send ACK / NACK messages for broadcast / multicast. Alternatively, a UE may only report NACK (reporting only in the event of decoding failure).

[0159] In this way, different ACK / NACK reporting resources (e.g., at least one different resource in the time domain, frequency domain, and code domain) can be configured for multiple UEs belonging to the same UE group. The ACK / NACK reporting resources can also be notified to each UE from the base station using at least one of downlink control information and higher-layer signaling.

[0160] The base station can also perform retransmission control for each UE individually based on whether ACK / NACK is detected in the resources configured for each UE (e.g., determining whether to retransmit). For example, the base station can also retransmit only to UEs that reported NACK. In this case, the base station can also selectively retransmit retransmission information (e.g., transport blocks) for information transmitted via broadcast / multicast to specific UEs using unicast transmission.

[0161] Therefore, it is possible to retransmit only to UEs that failed to decode information sent via broadcast / multicast. As a result, since UEs that have successfully decoded the information do not need to receive the retransmitted information, the increased processing burden on those UEs can be reduced.

[0162] Alternatively, the base station can determine the retransmission method based on the number of UEs that sent NACK (or UEs that sent ACK). For example, if the number of UEs reporting NACK is above a predetermined value (or the number of UEs reporting ACK is below a specific value), retransmission can be performed via broadcast / multicast. In this case, UEs that did not report NACK (or UEs that reported ACK) can skip the reception processing (e.g., decoding) of the retransmitted information.

[0163] (Wireless Communication System)

[0164] The structure of a wireless communication system according to one embodiment of this disclosure will be described below. In this wireless communication system, communication is performed using any one or a combination of the wireless communication methods according to the above embodiments of this disclosure.

[0165] Figure 8This is a diagram illustrating an example of the schematic structure of a wireless communication system according to one embodiment. The wireless communication system 1 may also be a system that uses Long Term Evolution (LTE), 5th generation mobile communication system New Radio (5G NR), etc., which are standardized by the Third Generation Partnership Project (3GPP).

[0166] Furthermore, the wireless communication system 1 can also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC can also include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0167] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0168] Wireless communication system 1 can also support dual connectivity between multiple base stations within the same RAT (e.g., MN and SN are dual connectivity of NR base stations (gNB) (NR-NR Dual Connectivity (NN-DC))).

[0169] The wireless communication system 1 may also include: a base station 11 forming a macro cell C1 with a relatively wide coverage area, and a base station 12 (12a-12c) configured within the macro cell C1 and forming a small cell C2 narrower than the macro cell C1. User terminals 20 may also be located within at least one cell. The configuration and number of each cell and user terminals 20 are not limited to the arrangement shown in the figure. Hereinafter, without distinguishing between base stations 11 and 12, they will be collectively referred to as base station 10.

[0170] User terminal 20 may also connect to at least one of multiple base stations 10. User terminal 20 may also utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

[0171] Each CC can 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)). Macro cell C1 can also be included in FR1, and small cell C2 can also be included in FR2. For example, FR1 can also be a frequency band below 6 GHz (sub-6 GHz), and FR2 can also be a frequency band above 24 GHz (above-24 GHz). Furthermore, the frequency bands and definitions of FR1 and FR2 are not limited to these; for example, FR1 can also correspond to a frequency band higher than FR2.

[0172] In addition, user terminal 20 can also communicate in each CC using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD).

[0173] Multiple base stations 10 can also be connected via wired (e.g., fiber optic cable based on the Common Public Radio Interface (CPRI), X2 interface, etc.) or wireless (e.g., NR communication). For example, when NR communication is used as a backhaul between base stations 11 and 12, base station 11, which is equivalent to a host station, can also be called an Integrated Access Backhaul (IAB) donor, and base station 12, which is equivalent to a relay station, can also be called an IAB node.

[0174] Base station 10 may also be connected to core network 30 via other base stations 10 or directly. Core network 30 may include, for example, at least one of Evolved Packet Core (EPC), 5G Core Network (5GCN), Next Generation Core (NGC), etc.

[0175] User terminal 20 can also be a terminal that supports at least one of the following communication methods: LTE, LTE-A, 5G, etc.

[0176] In wireless communication system 1, wireless access methods based on Orthogonal Frequency Division Multiplexing (OFDM) can also be used. For example, in at least one of the downlink (DL) and uplink (UL) links, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), and Single Carrier Frequency Division Multiple Access (SC-FDMA) can also be used.

[0177] The wireless access method can also be referred to as a waveform. In addition, in the wireless communication system 1, other wireless access methods (e.g., other single-carrier transmission methods, other multi-carrier transmission methods) can also be applied to the wireless access methods of UL and DL.

[0178] In the wireless communication system 1, the downlink channel can also be a shared downlink channel (Physical Downlink Shared Channel (PDSCH)), a broadcast channel (Physical Broadcast Channel (PBCH)), or a downlink control channel (Physical Downlink Control Channel (PDCCH)) shared by each user terminal 20.

[0179] In addition, in the wireless communication system 1, the uplink channel can also be an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), an uplink control channel (Physical Uplink Control Channel (PUCCH)), or a random access channel (Physical Random Access Channel (PRACH)) shared by each user terminal 20.

[0180] User data, high-level control information, and System Information Blocks (SIBs) are transmitted via the PDSCH. User data and high-level control information can also be transmitted via the PUSCH. Furthermore, the Master Information Block (MIB) can be transmitted via the PBCH.

[0181] Lower-layer control information can also be transmitted via PDCCH. This lower-layer control information may include, for example, downlink control information (DCI), which includes scheduling information for at least one of PDSCH and PUSCH.

[0182] Additionally, the DCI for scheduling PDSCH can also be called DL allocation, DL DCI, etc., and the DCI for scheduling PUSCH can also be called UL authorization, UL DCI, etc. Furthermore, PDSCH can also be renamed DL data, and PUSCH can also be renamed UL data.

[0183] In PDCCH detection, a Control Resource Set (CORESET) and a search space can be utilized. A CORESET corresponds to the resources used to search for DCIs. The search space corresponds to the search area and search method for PDCCH candidates. A CORESET can be associated with one or more search spaces. The UE can also monitor CORESETs associated with a specific search space based on search space settings.

[0184] A search space can also correspond to a PDCCH candidate that matches one or more aggregation levels. One or more search spaces can also be called a search space set. In addition, the terms "search space", "search space set", "search space setting", "search space set setting", "CORESET", and "CORESET setting" used in this disclosure can be used interchangeably.

[0185] Uplink control information (UCI) can also be transmitted via PUCCH, including at least one of the following: Channel State Information (CSI), delivery confirmation information (e.g., Hybrid Automatic Repeat Request ACK Knowledge (HARQ-ACK), ACK / NACK, etc.), and Scheduling Request (SR). Random access preambles used for establishing a connection with the cell can also be transmitted via PRACH.

[0186] Additionally, in this disclosure, downlink, uplink, etc., may be described without the word "link". Furthermore, it may be described without "physical" at the beginning of various channels.

[0187] In wireless communication system 1, synchronization signals (SS) and downlink reference signals (DL-RS) can also be transmitted. In wireless communication system 1, as DL-RS, cell-specific reference signals (CRS), channel state information reference signals (CSI-RS), demodulation reference signals (DMRS), positioning reference signals (PRS), and phase tracking reference signals (PTRS) can also be transmitted.

[0188] Synchronization signals can be, for example, at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). A signal block containing SS (PSS, SSS) and PBCH (and DMRS for PBCH) can also be called an SS / PBCH block, SS block (SSB), etc. Additionally, SS, SSB, etc., can also be called reference signals.

[0189] Furthermore, in wireless communication system 1, the uplink reference signal (UL-RS) can also transmit measurement reference signals (sounding reference signals (SRS)) and demodulation reference signals (DMRS). Additionally, DMRS can also be referred to as user terminal-specific reference signals (UE-specific reference signals).

[0190] (Base station)

[0191] Figure 9 This diagram illustrates an example of the structure of a base station according to one embodiment. The base station 10 includes a control unit 110, a transmit / receive unit 120, a transmit / receive antenna 130, and a transmission path interface (transmission line interface) 140. Alternatively, the control unit 110, the transmit / receive unit 120, the transmit / receive antenna 130, and the transmission path interface 140 may each be provided in more than one manner.

[0192] Furthermore, while this example primarily illustrates the functional blocks of the characteristic portions of this embodiment, it is also conceivable that the base station 10 may also have other functional blocks required for wireless communication. Some of the processing of each unit described below may also be omitted.

[0193] The control unit 110 performs overall control of the base station 10. The control unit 110 can be composed of a controller, control circuit, etc., which are described based on common knowledge in the art to which this disclosure pertains.

[0194] The control unit 110 can also control signal generation and scheduling (e.g., resource allocation, mapping). The control unit 110 can also control transmission, reception, and measurement using the transmit / receive unit 120, transmit / receive antenna 130, and transmission path interface 140. The control unit 110 can also generate data, control information, sequences, etc., to be transmitted as signals and forward them to the transmit / receive unit 120. The control unit 110 can also perform call processing (setting, releasing, etc.) of the communication channel, status management of the base station 10, and management of wireless resources.

[0195] The transmitting / receiving unit 120 may also include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may also include a transmitting processing unit 1211 and a receiving processing unit 1212. The transmitting / receiving unit 120 can be composed of transmitters / receivers, RF circuits, baseband circuits, filters, phase shifters, measurement circuits, transmitting / receiving circuits, etc., as described based on common knowledge in the art to which this disclosure pertains.

[0196] The transmitting and receiving unit 120 can be configured as a single integrated transmitting and receiving unit, or it can be configured as a transmitting unit and a receiving unit. The transmitting unit can also be configured as a transmitting processing unit 1211 and an RF unit 122. The receiving unit can also be configured as a receiving processing unit 1212, an RF unit 122, and a measurement unit 123.

[0197] The transmitting and receiving antenna 130 can be constructed from an antenna, such as an array antenna, as described based on common knowledge in the art to which this disclosure pertains.

[0198] The transmitting / receiving unit 120 can also transmit the aforementioned downlink channel, synchronization signal, downlink reference signal, etc. The transmitting / receiving unit 120 can also receive the aforementioned uplink channel, uplink reference signal, etc.

[0199] The transmitting and receiving unit 120 may also use digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc., to form at least one of the transmitting beam and the receiving beam.

[0200] The transmitting and receiving unit 120 (transmitting processing unit 1211) may, for example, perform processing at the Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer (e.g., RLC retransmission control), and Medium Access Control (MAC) layer (e.g., HARQ retransmission control) on the data and control information obtained from the control unit 110, and generate a bit string to be transmitted.

[0201] The transmitting and receiving unit 120 (transmitting processing unit 1211) can also perform channel coding (which may 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 transmitted, and output the baseband signal.

[0202] The transmitting and receiving unit 120 (RF unit 122) can also perform modulation, filtering, amplification, etc. on the baseband signal to the wireless frequency band, and transmit the wireless frequency band signal through the transmitting and receiving antenna 130.

[0203] On the other hand, the transmitting and receiving unit 120 (RF unit 122) can also amplify, filter, and demodulate the signals of the wireless frequency band received by the transmitting and receiving antenna 130 into the baseband signal.

[0204] The transmitting and receiving unit 120 (receiving and processing unit 1212) can also perform receiving and processing on the acquired baseband signal, including 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, to obtain user data.

[0205] The transmitting / receiving unit 120 (measurement unit 123) can also perform measurements related to the received signal. For example, the measurement unit 123 can also perform radio resource management (RRM) measurements, channel state information (CSI) measurements, etc., based on the received signal. The measurement unit 123 can also measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results can also be output to the control unit 110.

[0206] The transmission path interface 140 can also transmit and receive signals (backhaul signaling) between the device included in the core network 30 and other base stations 10, and can also acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0207] In addition, the transmitting unit and receiving unit of the base station 10 in this disclosure can also be configured by at least one of the transmitting / receiving unit 120, the transmitting / receiving antenna 130 and the transmission path interface 140.

[0208] In addition, the transmitting and receiving unit 120 transmits specific information using at least one of broadcasting and multicasting. The transmitting and receiving unit 120 can also receive retransmission control information for specific information transmitted using at least one of broadcasting and multicasting.

[0209] The control unit 110 can also be controlled to set whether to apply retransmission control for specific information sent using at least one of broadcast and multicast to the UE.

[0210] In addition, the control unit 110 can also perform control to set the transmission timing for retransmission control of specific information transmitted using at least one of broadcast and multicast for the UE.

[0211] In addition, the control unit 110 can also perform control to set the transmission power for the UE for retransmission control of specific information transmitted by utilizing at least one of broadcast and multicast.

[0212] In addition, the control unit 110 can also perform control to set resources for the UE to control the retransmission of specific information sent using at least one of broadcast and multicast.

[0213] (User terminal)

[0214] Figure 10 This diagram illustrates an example of the structure of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transmitting / receiving unit 220, and a transmitting / receiving antenna 230. Alternatively, the control unit 210, the transmitting / receiving unit 220, and the transmitting / receiving antenna 230 may each be provided as one or more.

[0215] Furthermore, while this example primarily illustrates the functional blocks of the characteristic portions of this embodiment, it is also conceivable that the user terminal 20 may also have other functional blocks required for wireless communication. Some of the processing of each unit described below may also be omitted.

[0216] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be composed of a controller, control circuit, etc., which are described based on common knowledge in the art to which this disclosure pertains.

[0217] The control unit 210 can also control signal generation, mapping, etc. The control unit 210 can also control transmission, reception, measurement, etc., using the transmission / reception unit 220 and the transmission / reception antenna 230. The control unit 210 can also generate data, control information, sequences, etc., to be transmitted as signals and forward them to the transmission / reception unit 220.

[0218] The transmitting / receiving unit 220 may also include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may also include a transmitting processing unit 2211 and a receiving processing unit 2212. The transmitting / receiving unit 220 may be composed of a transmitter / receiver, RF circuit, baseband circuit, filter, phase shifter, measurement circuit, transmitting / receiving circuit, etc., as described based on common knowledge in the art to which this disclosure pertains.

[0219] The transmitting and receiving unit 220 can be configured as a single integrated transmitting and receiving unit, or it can be composed of a transmitting unit and a receiving unit. The transmitting unit can also be composed of a transmitting processing unit 2211 and an RF unit 222. The receiving unit can also be composed of a receiving processing unit 2212, an RF unit 222, and a measurement unit 223.

[0220] The transmitting and receiving antenna 230 can be constructed from an antenna, such as an array antenna, as described based on common knowledge in the art to which this disclosure pertains.

[0221] The transmitting / receiving unit 220 can also receive the downlink channel, synchronization signal, downlink reference signal, etc., mentioned above. The transmitting / receiving unit 220 can also transmit the uplink channel, uplink reference signal, etc., mentioned above.

[0222] The transmitting and receiving unit 220 may also use digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc., to form at least one of the transmitting beam and the receiving beam.

[0223] The transmitting and receiving unit 220 (transmitting processing unit 2211) may, for example, perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control) on the data and control information obtained from the control unit 210, and generate the bit string to be transmitted.

[0224] The transmitting and receiving unit 220 (transmitting processing unit 2211) can also perform channel coding (which may 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 transmitted, and output the baseband signal.

[0225] Furthermore, whether or not to apply DFT processing can be based on the transform precoding settings. For a certain channel (e.g., PUSCH), if transform precoding is active (enabled), the transmit / receive unit 220 (transmit processing unit 2211) can perform DFT processing as described above for transmitting the channel using the DFT-s-OFDM waveform. If not, the transmit / receive unit 220 (transmit processing unit 2211) can perform the above transmission processing without performing DFT processing.

[0226] The transmitting and receiving unit 220 (RF unit 222) can also perform modulation, filtering, amplification, etc. on the baseband signal to the wireless frequency band, and transmit the wireless frequency band signal through the transmitting and receiving antenna 230.

[0227] On the other hand, the transmitting and receiving unit 220 (RF unit 222) can also amplify, filter, and demodulate the baseband signal for the wireless frequency band signal received by the transmitting and receiving antenna 230.

[0228] The transmitting and receiving unit 220 (receiving and processing unit 2212) can also perform receiving and processing on the acquired baseband signal, such as 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 acquire user data.

[0229] The transmitting / receiving unit 220 (measurement unit 223) can also perform measurements related to the received signal. For example, the measurement unit 223 can also perform RRM measurements, CSI measurements, etc., based on the received signal. The measurement unit 223 can 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 can also be output to the control unit 210.

[0230] In addition, the transmitting unit and receiving unit of the user terminal 20 in this disclosure can also be configured by at least one of the transmitting / receiving unit 220 and the transmitting / receiving antenna 230.

[0231] Additionally, the transmitting / receiving unit 220 receives specific information transmitted via at least one of broadcasting and multicasting. Furthermore, the transmitting / receiving unit 220 can transmit retransmission control information for specific information transmitted via at least one of broadcasting and multicasting.

[0232] The control unit 210 may also determine whether to send retransmission control information for a specific piece of information based on at least one of the information sent from the network and the conditions applied to the transmission of that specific information. For example, the control unit 210 may also determine whether to send retransmission control information for a specific piece of information based on at least one of whether repeated transmission of that specific information is applied, the MCS applied to that specific information, and the coding rate applied to that specific information. Furthermore, the control unit 210 may be designed to have a process number commonly set for retransmission control of that specific information and a process number used for retransmission control of information transmitted via unicast. Alternatively, the control unit 210 may be designed to have the process number used for retransmission control of that specific information and the process number used for retransmission control of information transmitted via unicast set separately.

[0233] The control unit 210 can also determine the transmission timing of retransmission control information for specific information based on at least one of predefined values ​​and information transmitted from the network. Furthermore, the control unit 210 can select a specific transmission timing based on information relating to a candidate set of transmission timings for retransmission control information for specific information and downlink control information publicly transmitted to a specific user terminal. Additionally, the control unit 210 can determine the transmission timing of retransmission control information for specific information based on a first transmission timing parameter notified via higher-layer signaling and a second transmission timing parameter notified via downlink control information. Furthermore, the control unit 210 can determine the resources used in transmitting retransmission control information for specific information based on a first resource parameter notified via higher-layer signaling and a second resource parameter specified using at least one of higher-layer signaling and downlink control information. Additionally, the control unit 210 can select specific resources based on a candidate set of resources used in transmitting retransmission control information for specific information and downlink control information publicly transmitted to a specific user terminal.

[0234] The control unit 210 may also determine the uplink channel transmission power used in transmitting retransmission control information for specific information based on transmission power parameters notified separately to each user terminal. Furthermore, the control unit 210 may be designed to separately set at least one of the transmission power parameter value and the transmission timing of the retransmission control information for each user terminal. Additionally, the control unit 210 may determine the transmission power based on a first transmission power parameter notified via higher-layer signaling and a second transmission power parameter specified using at least one of higher-layer signaling and downlink control information. Furthermore, the control unit 210 may determine the transmission power based on a transmission power control command contained in downlink control information that is different from the downlink control information used to schedule specific information.

[0235] The control unit 210 can also utilize resources shared among multiple user terminals to control the reporting of retransmission control information for specific information. Furthermore, the control unit 210 can control the reporting of only one of ACK and NACK as retransmission control information. Additionally, when the retransmission of specific information is sent via broadcast or multicast, the control unit 210 can decide whether to receive the retransmitted information based on the reception result of the specific information. Furthermore, the control unit 210 can also utilize resources separately allocated among user terminals to control the reporting of retransmission control information for specific information. Moreover, the control unit 210 can also envision the retransmission of specific information being sent via unicast.

[0236] (Hardware Structure)

[0237] Furthermore, the block diagrams used in the description of the above embodiments illustrate functional units. These functional blocks (structural units) are implemented through any combination of at least one of hardware and software. Moreover, the implementation method of each functional block is not particularly limited. That is, each functional block can be implemented using a single device that is physically or logically combined, or it can be implemented by directly or indirectly (e.g., using wired, wireless, etc.) connecting two or more physically or logically separate devices. A functional block can also be implemented by combining one or more of the aforementioned devices with software.

[0238] Here, the functions include judgment, decision, determination, calculation, calculation, processing, export, investigation, search, confirmation, receiving, sending, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, regard as, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assigning, but are not limited to these. For example, the functional block (structural unit) that implements the sending function can also be called a transmitting unit, transmitter, etc. As described above, the implementation method is not particularly limited.

[0239] For example, in one embodiment of this disclosure, the base station, user terminal, etc., can also function as a computer for processing the wireless communication method of this disclosure. Figure 11 This diagram illustrates an example of the hardware structure of a base station and a user terminal according to one embodiment. The base station 10 and the user terminal 20 described above can also be physically configured as a computer device including a processor 1001, a memory 1002, a storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0240] Furthermore, in this disclosure, terms such as apparatus, circuit, device, section, and unit can be used interchangeably. The hardware structure of base station 10 and user terminal 20 can also be configured to include one or more of the apparatuses shown in the figures, or it can be configured not to include any of the apparatuses.

[0241] For example, only one processor 1001 is shown, but there can be multiple processors. Furthermore, processing can be performed by a single processor, or simultaneously, sequentially, or by two or more processors using other methods. Additionally, processor 1001 can be implemented using more than one chip.

[0242] The functions of the base station 10 and the user terminal 20 are implemented, for example, by reading specific software (programs) 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 reading out and writing data in the memory 1002 and the storage device 1003.

[0243] The processor 1001, for example, enables the operating system to operate and control the computer as a whole. The processor 1001 may also be configured as a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic devices, registers, etc. For example, at least a portion of the control unit 110 (210), the transmit / receive unit 120 (220), etc., described above may also be implemented by the processor 1001.

[0244] Furthermore, the processor 1001 reads programs (program code), software modules, data, etc., from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and performs various processes accordingly. As a program, a program that causes the computer to perform at least a portion of the operations described in the above 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 operating in the processor 1001; similar implementations can be made for other functional blocks.

[0245] The memory 1002 may also be a computer-readable recording medium, such as being composed of at least one of read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), random access memory (RAM), or other suitable storage media. The memory 1002 may also be referred to as a register, cache, main memory (main storage device), etc. The memory 1002 is capable of storing executable programs (program code), software modules, etc., for implementing the wireless communication method according to one embodiment of the present disclosure.

[0246] Storage 1003 may also be a computer-readable recording medium, such as at least one of a flexible disc, floppy disk, optical disk (e.g., compact disc ROM, CD-ROM), digital multifunction disk, Blu-ray disc, removable disk, hard disk, smart card, flash memory device (e.g., card, stick, key drive), magnetic stripe, database, server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0247] The communication device 1004 is hardware (transmitting and receiving device) used for communication between computers via at least one of a wired network and a wireless network. It is also referred to as a network device, network controller, network interface card (NIC), communication module, etc. To implement at least one of, for example, Frequency Division Duplex (FDD) and Time Division Duplex (TDD), the communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. For example, the aforementioned transmit / receive unit 120 (220) and transmit / receive antenna 130 (230) may also be implemented by the communication device 1004. The transmit / receive unit 120 (220) may also be physically or logically separated from the transmit unit 120a (220a) and the receive unit 120b (220b).

[0248] Input device 1005 is an input device that receives input from external sources (e.g., keyboard, mouse, microphone, switch, button, sensor, etc.). Output device 1006 is an output device that performs output to external sources (e.g., display, speaker, light-emitting diode (LED) lamp, etc.). Alternatively, input device 1005 and output device 1006 can also be an integrated structure (e.g., touch panel).

[0249] Furthermore, the processor 1001, memory 1002, and other devices are connected via a bus 1007 for communication of information. The bus 1007 can be a single bus or different buses can be used between the devices.

[0250] Furthermore, the base station 10 and the user terminal 20 can 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), or a field-programmable gate array (FPGA), and such hardware can be used to implement part or all of the functional blocks. For example, the processor 1001 can also be installed using at least one of these hardware components.

[0251] (Modified Example)

[0252] Furthermore, the terms described in this disclosure and those necessary for understanding this disclosure may be replaced with terms that have the same or similar meanings. For example, channel, symbol, and signal (signal or signaling) may be used interchangeably. Additionally, a signal may also be a message. A reference signal may also be abbreviated as RS, and may be referred to as pilot, pilot signal, etc., depending on the applied standard. Furthermore, a component carrier (CC) may also be referred to as cell, frequency carrier, carrier frequency, etc.

[0253] A radio frame can also be composed of one or more periods (frames) in the time domain. These one or more periods (frames) that constitute a radio frame can also be called subframes. Furthermore, a subframe can also be composed of one or more time slots in the time domain. A subframe can also be a fixed time length (e.g., 1 ms) independent of the parameter set (numerology).

[0254] Here, the parameter set can also refer to communication parameters applied in at least one of the transmission and reception of a signal or channel. For example, the parameter set can also represent at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering processing performed by the transmitter and receiver in the frequency domain, and specific windowing processing performed by the transmitter and receiver in the time domain.

[0255] In the time domain, a time slot can also be composed of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.). Furthermore, a time slot can also be a time unit based on a set of parameters.

[0256] A time slot can also contain multiple mini-time slots. Each mini-time slot can also consist of one or more symbols in the time domain. Furthermore, a mini-time slot can also be called a sub-time slot. A mini-time slot can also consist of fewer symbols than a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-time slot can also be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using mini-time slots can also be called PDSCH (PUSCH) mapping type B.

[0257] 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 can also use their respective other names. Furthermore, the time units such as frames, subframes, time slots, mini-time slots, and symbols used in this disclosure can be interchanged.

[0258] For example, a subframe can also be called a TTI, multiple consecutive subframes can also be called a TTI, a time slot or a mini-time slot can also be called a TTI. That is to say, at least one of the subframe and TTI can be a subframe in the existing LTE (1ms), a period shorter than 1ms (e.g., 1-13 symbols), or a period longer than 1ms. In addition, the unit representing TTI may not be called a subframe, but a time slot, mini-time slot, etc.

[0259] Here, TTI refers, for example, to the smallest unit of time for scheduling in wireless communication. For instance, in an LTE system, the base station schedules radio resources (frequency bandwidth, transmit power, etc., available to each user terminal) in TTI units. However, the definition of TTI is not limited to this.

[0260] TTI can also be a unit of time for transmitting channel-coded data packets (transmission blocks), code blocks, codewords, etc., and can also be a unit of processing such as scheduling and link adaptation. In addition, when a TTI is given, the actual time interval (e.g., the number of symbols) that the transmission block, code block, codeword, etc. are mapped to can be shorter than the TTI.

[0261] Furthermore, when a time slot or a mini-time slot is referred to as a TTI, more than one TTI (i.e., more than one time slot or more than one mini-time slot) can also serve as the minimum time unit for scheduling. In addition, the number of time slots constituting the minimum time unit of the schedule (the number of mini-time slots) can also be controlled.

[0262] A Time Interval (TTI) with a duration of 1 ms can 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 can 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.

[0263] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) can also be referred to as a TTI with a duration of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) can also be referred to as a TTI with a duration of less than a long TTI but more than 1 ms.

[0264] A resource block (RB) is a unit of resource allocation in the time and frequency domains. In the frequency domain, it can contain one or more consecutive subcarriers. The number of subcarriers in an RB can be the same regardless of the parameter set, for example, it can be 12. The number of subcarriers in an RB can also be determined based on the parameter set.

[0265] Furthermore, an RB can contain one or more symbols in the time domain, and can also be a time slot, a mini-time slot, a subframe, or the length of a TTI. A TTI, a subframe, etc., can also be composed of one or more resource blocks.

[0266] In addition, one or more RBs can also be referred to as Physical Resource Blocks (PRBs), Sub-Carrier Groups (SCGs), Resource Element Groups (REGs), PRB pairs, RB pairs, etc.

[0267] Furthermore, a resource block can also consist of one or more resource elements (REs). For example, an RE can also be a radio resource area consisting of a subcarrier and a symbol.

[0268] The Bandwidth Part (BWP) (also referred to as partial bandwidth, etc.) can also represent a subset of consecutive common resource blocks (RBs) used for a certain parameter set in a carrier. Here, common RBs can also be determined by indexing RBs based on a common reference point of the carrier. PRBs can also be defined in a BWP and appended with numbers within that BWP.

[0269] A BWP can also include a UL BWP (BWP used by UL) and a DL BWP (BWP used by DL). For a UE, one or more BWPs can be set within a single carrier.

[0270] At least one of the configured BWPs can be active, and the UE may not intend to transmit or receive specific signals / channels outside of the active BWPs. Furthermore, the terms "cell," "carrier," etc., used in this disclosure may be replaced with "BWP."

[0271] Furthermore, the structures of radio frames, subframes, time slots, mini-time slots, and symbols described above are merely illustrative. For example, the number of subframes contained in a radio frame, the number of time slots in each subframe or radio frame, the number of mini-time slots contained within a time slot, the number of symbols and RBs contained in a time slot or mini-time slot, the number of subcarriers contained in an RB, and the number of symbols in a TTI, symbol length, cyclic prefix (CP) length, and other structures can be varied in many ways.

[0272] Furthermore, the information, parameters, etc., described in this disclosure can be represented by absolute values, relative values ​​with respect to a specific value, or other corresponding information. For example, wireless resources can also be indicated by a specific index.

[0273] In this disclosure, the names used for parameters, etc., are not limiting names in any respect. Furthermore, the mathematical expressions, etc., using these parameters may differ from those explicitly disclosed in this disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name; therefore, the various names assigned to these various channels and information elements are not limiting names in any respect.

[0274] The information, signals, etc., described in this disclosure can also be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc., which may be mentioned throughout the above description, can also be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination thereof.

[0275] Furthermore, information and signals can be output in at least one direction, from higher layers to lower layers and from lower layers to higher layers. Information and signals can also be input and output via multiple network nodes.

[0276] Input and output information and signals can be stored in a specific location (such as memory) or managed using management tables. Input and output information and signals can be overwritten, updated, or appended. Output information and signals can also be deleted. Input information and signals can also be sent to other devices.

[0277] The notification of information is not limited to the methods / implementations described in this disclosure, and may also be carried out by other methods. For example, the notification of information in this disclosure may also be implemented through physical layer signaling (e.g., downlink control information (DCI), uplink control information (UCI), etc.), higher 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 combinations thereof.

[0278] In addition, physical layer signaling can also be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signals), L1 control information (L1 control signals), etc. Furthermore, RRC signaling can also be referred to as RRC messages, such as RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc. Additionally, MAC signaling can also be notified using, for example, the MAC Control Element (CE).

[0279] Furthermore, notification of specific information (e.g., a notification that “is X”) is not limited to explicit notification, but can also be implicit (e.g., by not providing that specific information, or by providing other information).

[0280] The determination can be made by a value represented by a single bit (0 or 1), by a true or false value (boolean), or by a numerical comparison (e.g., a comparison with a specified value).

[0281] Whether it is called software, firmware, middleware, microcode, hardware description language, or any other name, software should be broadly interpreted as instructions, instruction sets, code, code segments, program code, program, subprogram, software module, application, software application, software package, routine, subroutine, object, executable file, execution thread, process, function, etc.

[0282] Furthermore, software, instructions, and information can 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 technologies (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL) etc.) and wireless technologies (infrared, microwave, etc.), at least one of these wired and wireless technologies is included within the definition of a transmission medium.

[0283] The terms “system” and “network” as used in this disclosure are used interchangeably. “Network” may also mean devices included in a network (e.g., base stations).

[0284] In this disclosure, the terms "precoding", "precoder", "weight (precoding weight)", "quasi-co-location (QCL)", "transmission configuration indication state (TCI state)", "spatial relation", "spatial domain filter", "transmit power", "phase rotation", "antenna port", "antenna port group", "layer", "number of layers", "rank", "resource", "resource set", "resource group", "beam", "beamwidth", "beam angle", "antenna", "antenna element", and "panel" are used interchangeably.

[0285] In this disclosure, the terms "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" are used interchangeably. There are also instances where the terms macrocell, small cell, femtocell, and picocell are used to refer to a base station.

[0286] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, its coverage area can be divided into several smaller areas, each of which can provide communication services through a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). Terms such as "cell" or "sector" refer to a portion or all of the coverage area of ​​at least one of the base station and base station subsystem providing communication services within that coverage area.

[0287] In this disclosure, the terms "Mobile Station (MS)", "user terminal", "User Equipment (UE)", and "terminal" are used interchangeably.

[0288] In some cases, a mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, hand set, user agent, mobile client, client, or several other appropriate terms.

[0289] At least one of the base station and the mobile station can also be referred to as a transmitting device, a receiving device, a wireless communication device, etc. Additionally, at least one of the base station and the mobile station can also be a device mounted on a mobile body, or the mobile body itself. This mobile body can be a vehicle (e.g., a car, an airplane, etc.), a mobile body moving unmanned (e.g., a drone, an autonomous vehicle, etc.), or a robot (humanized or unmanned). Furthermore, at least one of the base station and the mobile station also includes devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station can also be an Internet of Things (IoT) device such as a sensor.

[0290] Furthermore, the base station in this disclosure can also be referred to as a user terminal. For example, various methods / implementations of this disclosure can also be applied to structures that replace the communication between the base station and the user terminal with communication between multiple user terminals (e.g., also referred to as device-to-device (D2D) or vehicle-to-everything (V2X)). In this case, it can also be configured such that the user terminal 20 has the functions of the base station 10 described above. In addition, terms such as "uplink" and "downlink" can also be referred to as terms corresponding to inter-terminal communication (e.g., "side"). For example, uplink channel, downlink channel, etc. can also be referred to as side channel.

[0291] Similarly, the user terminal in this disclosure can also be referred to as a base station. In this case, it can also be configured such that the base station 10 has the functions of the user terminal 20 described above.

[0292] In this disclosure, operations purported to be performed by the base station are sometimes also performed by its upper node, depending on the circumstances. Obviously, in a network containing one or more network nodes having a base station, various operations for communication with the terminal can also be performed by the base station, one or more network nodes other than the base station (e.g., considering a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc., but not limited to these), or combinations thereof.

[0293] The various methods / implementations described in this disclosure can be used individually, in combination, or switched as needed during execution. Furthermore, the processing procedures, sequences, flowcharts, etc., of the various methods / implementations described in this disclosure can be rearranged as long as they do not contradict each other. For example, with respect to the methods described in this disclosure, the illustrated order is used to indicate various steps, but the order in which they are indicated is not limited.

[0294] The various methods / implementations described in this disclosure can 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), 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), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE The terms include 802.20, Ultra-Wideband (UWB), Bluetooth (registered trademark), systems utilizing other appropriate wireless communication methods, and next-generation systems derived from them. Furthermore, multiple systems can be combined (e.g., LTE or LTE-A, combinations with 5G, etc.) for application.

[0295] As used in this disclosure, the word "based on" does not mean "based on only" unless otherwise specified. In other words, the word "based on" means both "based on only" and "based on at least".

[0296] Any reference to an element using the terms "first," "second," etc., as used in this disclosure does not comprehensively limit the quantity or order of these elements. These terms may be used in this disclosure as a convenient method of distinguishing between two or more elements. Therefore, references to the first and second elements do not imply that only two elements are permitted, or that the first element must take precedence over the second element in some form.

[0297] As used in this disclosure, the term "determining" can encompass a variety of operations in some cases. For example, "determining" can also be considered as making a "determination" regarding judging, calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, database, or other data structure), ascertaining, etc.

[0298] In addition, "judgment (decision)" can also be regarded as the situation of making "judgment (decision)" on receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0299] Furthermore, "judgment (decision)" can also be seen as making "judgments (decisions)" regarding resolving, selecting, choosing, establishing, and comparing. In other words, "judgment (decision)" can also be seen as making "judgments (decisions)" regarding certain operations.

[0300] In addition, "judgment (decision)" can also be replaced with "assuming", "expecting", "considering", etc.

[0301] The term "maximum transmit power" as used in this disclosure may refer to the maximum value of the transmit power, or it may refer to the nominal maximum transmit power (the nominal UE maximum transmit power) or the rated maximum transmit power (the rated UE maximum transmit power).

[0302] As used in this disclosure, the terms "connected," "coupled," or any variations thereof, mean any direct or indirect connection or combination between two or more elements, and can include cases where there is one or more intermediate elements between two mutually "connected" or "coupled" elements. The combination or connection between elements can be physical, logical, or a combination of these. For example, "connection" can also be replaced with "access."

[0303] In this disclosure, when connecting two elements, it is possible to “connect” or “combine” them by using one or more wires, cables, printed electrical connections, etc., and by using electromagnetic energy with wavelengths in the wireless frequency domain, microwave region, or light (both visible and invisible) region as one of several non-limiting and non-exclusive examples.

[0304] In this disclosure, the term "A is different from B" can also mean "A and B are different from each other". Additionally, the term can also mean "A and B are different from C respectively". Terms such as "separate" and "combined" can also be interpreted as "different".

[0305] In this disclosure, the terms "include," "including," and variations thereof, as used with respect to the term "comprising," mean inclusiveness. Furthermore, the term "or" as used in this disclosure does not mean XOR.

[0306] In this disclosure, for example, in cases where articles are added through translation such as a, an, and the in English, the disclosure may also include cases where the noun following these articles is in a plural form.

[0307] The invention disclosed herein has been described in detail above. However, it will be apparent to those skilled in the art that the invention is not limited to the embodiments described herein. The invention can be implemented as modifications and variations without departing from the spirit and scope of the invention as defined by the claims. Therefore, the description in this disclosure is for illustrative purposes only and is not intended to limit the invention in any way.

[0308] This application is based on patent application No. 2019-094079, filed on May 17, 2019. All of these contents are included herein.

Claims

1. A terminal, characterized in that, include: The receiving unit receives downlink control information (DCI) for scheduling specific information transmitted via at least one of broadcast and multicast, as well as the specific information; as well as The control unit, based on the information contained in the DCI indicating whether retransmission control is enabled, determines whether HARQ-ACK retransmission control information for the specific information has been sent. The control unit determines the transmission power of the uplink channel used in the transmission of the HARQ-ACK based on the transmission power parameters set for each terminal through higher-layer signaling.

2. The terminal according to claim 1, characterized in that, The specific information mentioned is the downlink shared channel (PDSCH).

3. The terminal according to claim 1, characterized in that, When the specific information is sent via the multicast, and the HARQ-ACK is applied based on information indicating whether or not the retransmission control is applied, it is supported to not send HARQ-ACK for the specific information sent via the broadcast.

4. A wireless communication method, characterized in that, include: The steps of receiving downlink control information (DCI) for scheduling specific information transmitted via at least one of broadcast and multicast, and said specific information; Based on the information contained in the DCI indicating whether there is retransmission control, a step is taken to determine whether HARQ-ACK retransmission control information for the specific information has been sent. as well as The step of determining the transmission power of the uplink channel used in the transmission of the HARQ-ACK based on the transmission power parameters set for each terminal through higher-layer signaling.

5. A base station, characterized in that, include: The transmitting unit transmits downlink control information (DCI) for scheduling the transmission of specific information via at least one of broadcast and multicast, as well as the specific information; as well as The control unit, using information contained in the DCI indicating whether retransmission control is enabled, instructs whether HARQ-ACK retransmission control information for the specific information in the terminal should be sent. The control unit sets transmission power parameters for each terminal via higher-layer signaling. These transmission power parameters are used to determine the transmission power of the uplink channel used in the transmission of the HARQ-ACK.

6. A system having a terminal and a base station, characterized in that, The terminal includes: The receiving unit receives downlink control information (DCI) for scheduling specific information transmitted via at least one of broadcast and multicast, and the specific information; and The control unit, based on the information contained in the DCI indicating whether retransmission control is enabled, determines whether HARQ-ACK retransmission control information for the specific information has been sent. The control unit determines the uplink channel transmission power used in the HARQ-ACK transmission based on the transmission power parameters set for each terminal via higher-layer signaling. The base station includes: The transmitting unit transmits the DCI and the specific information; and The control unit, using information contained in the DCI indicating whether retransmission control is enabled, indicates whether HARQ-ACK is being sent in the terminal. The control unit sets the transmit power parameters for each terminal via the higher-layer signaling.

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