CN114128379A - User terminal and wireless communication method - Google Patents

Abstract

Retransmission control for at least one of broadcast transmission and multicast transmission is appropriately controlled. The user terminal has: the mobile communication device includes a receiving unit that receives specific information transmitted by at least one of broadcasting and multicasting, and a control unit that controls reporting of retransmission control information for the specific information by using a resource that is set in common among a plurality of user terminals.

Description

User terminal and wireless communication method

Technical Field

The present disclosure relates to a user terminal and a wireless communication method in a next generation mobile communication system.

Background

In a Universal Mobile Telecommunications System (UMTS) network, Long Term Evolution (LTE) is standardized for the purpose of further high data rate, low latency, and the like (non-patent document 1). In addition, LTE-Advanced (3GPP rel.10-14) is standardized for the purpose of further large capacity, Advanced, and the like of LTE (Third Generation Partnership Project (3GPP)) versions (Release (Rel.))8, 9).

Successor systems of LTE are also being studied (e.g., also referred to as the 5th generation mobile communication system (5G)), 5G + (plus), New Radio (NR), 3GPP rel.15 and beyond).

Documents of the prior art

Non-patent document

Non-patent document 1: 3GPP TS 36.300V8.12.0 "Evolved Universal Radio Access (E-UTRA) and Evolved Universal Radio Access Network (E-UTRAN); (ii) an Overall description; stage 2(Release 8) ", 4 months 2010.

Disclosure of Invention

Problems to be solved by the invention

It is assumed that, in a future wireless communication system (for example, NR), unicast transmission for transmitting data individually to each user terminal (UE), broadcast transmission for transmitting data commonly to a plurality of UEs, and multicast transmission are supported as data transmission methods.

Furthermore, it is also being studied to support retransmission control (e.g., HARQ) for at least one of broadcast transmission and multicast transmission in NR. However, how to control retransmission control of broadcast transmission or multicast transmission has not been sufficiently studied.

Accordingly, it is an object of the present disclosure to provide a user terminal and a wireless communication method capable of appropriately controlling retransmission control for at least one of broadcast transmission and multicast transmission.

Means for solving the problems

A user terminal according to an aspect of the present disclosure is characterized by including: a receiving unit that receives specific information transmitted by at least one of broadcasting and multicasting; and a control unit configured to control reporting of retransmission control information for the specific information by using a resource commonly set among a plurality of user terminals.

ADVANTAGEOUS EFFECTS OF INVENTION

According to an aspect of the present disclosure, retransmission control for at least one of broadcast transmission and multicast transmission can be appropriately controlled.

Drawings

Fig. 1 is a diagram showing an example of broadcast/multicast transmission.

Fig. 2 is a diagram illustrating an example of retransmission control according to the first embodiment.

Fig. 3 is a diagram showing another example of retransmission control according to the first aspect.

Fig. 4 is a diagram illustrating an example of retransmission control according to the second embodiment.

Fig. 5 is a diagram illustrating an example of retransmission control according to the third embodiment.

Fig. 6 is a diagram illustrating an example of retransmission control according to the fourth embodiment.

Fig. 7 is a diagram showing another example of retransmission control according to the fourth aspect.

Fig. 8 is a diagram showing an example of a schematic configuration of a radio communication system according to an embodiment.

Fig. 9 is a diagram showing an example of the configuration of a base station according to an embodiment.

Fig. 10 is a diagram showing an example of the configuration of a user terminal according to an embodiment.

Fig. 11 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment.

Detailed Description

It is envisaged that in future wireless communication systems (e.g. NRs), Unicast transmission (Unicast transmission), Broadcast transmission (Broadcast transmission) and multicast transmission (multicast transmission) will be supported. In unicast transmission, data or channels may be transmitted to each UE individually (e.g., UE-specific). At least one of the broadcast transmission and the multicast transmission (hereinafter, also referred to as broadcast/multicast transmission) may commonly transmit data or a channel to a plurality of UEs (e.g., a UE group).

The unicast transmission, the broadcast transmission, and the multicast transmission may each apply a different channel (at least one of a logical channel and a physical channel). Alternatively, the same structure may be used for broadcast transmission and multicast transmission.

Broadcast/multicast transmission becomes a transmission method effective in distributing information of the same content to a plurality of UEs (for example, a specific UE group). Therefore, it is assumed that a notification is broadcast/multicast for information on Public safety (Public safety) and high-speed traffic Systems (ITS) such as distribution of road conditions, traffic sign (traffic sign), and traffic light (traffic light) conditions. Alternatively, broadcast/multicast transmissions are envisaged for notifying viewers at a concert or a gym of information.

In NR, retransmission control (e.g., HARQ operation) for broadcast/multicast transmission may also be considered. However, how to control retransmission control of broadcast/multicast transmission has not been sufficiently studied. If retransmission control is not appropriately performed, communication quality and the like may deteriorate.

The present inventors have studied retransmission control for broadcast/multicast transmission, and have completed the present invention.

Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. Aspects of the various implementations may be applied separately or in combination. In the following description, HARQ-based retransmission (HARQ-based Re-transmission) is described as an example of retransmission control, but the present invention is not limited thereto.

In the following description, retransmission control for broadcast transmission may be referred to as retransmission control for information transmitted by broadcast instead. The information transmitted through broadcasting may also be referred to as at least one of data, a data channel, a DL-SCH, a broadcast channel, control information, DCI, a control channel, and broadcast control information instead. Retransmission control for multicast transmission may be referred to as retransmission control for information transmitted by multicast instead. The information transmitted through the multicast may also be referred to as at least one of data, a data channel, DL-SCH, a multicast channel, control information, DCI, a control channel, and multicast control information instead.

The information transmitted by broadcast/multicast may be included in data (e.g., DL-SCH, shared channel, etc.) scheduled by downlink control information (e.g., DCI), may be included in DCI, may be transmitted by higher layer signaling (e.g., at least one of RRC signaling and broadcast information), or may be transmitted by a dedicated signal or channel. In the case where information transmitted by broadcast/multicast is included in data, the DCI scheduling the data may also apply broadcast/multicast transmission. In the following description, such description may be applied to at least one of unicast transmission (or UE-specific transmission) and broadcast/multicast transmission (or UE-common transmission) by DCI or higher layer signaling transmission.

(first mode)

A first approach describes retransmission control for broadcast/multicast transmissions.

Fig. 1 shows an example of a case where a base station transmits specific information to a plurality of UEs (for example, a UE group) by using at least one of broadcasting and multicasting (hereinafter, also referred to as broadcasting/multicasting). Here, the case where the base station performs broadcast/multicast transmission to the UE group #1 and the UE group #2, respectively, is shown. The number of UE groups, UEs constituting the UE groups, and the like may be appropriately changed and applied.

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

< option 1>

The UE may decide whether to apply retransmission control for information transmitted through broadcast/multicast based on higher layer signaling. The base station may notify whether or not retransmission control is applied for each UE by using higher layer signaling, or may notify whether or not retransmission control is applied for each UE group.

When broadcast transmission (for example, transmission using a broadcast channel) and multicast transmission (for example, transmission using a multicast channel) are separately supported, whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission may be separately set. This makes it possible to flexibly control whether or not retransmission control is applied.

Alternatively, in the case where broadcast transmission and multicast transmission are separately supported, whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission may be commonly set. In this case, if whether or not to apply retransmission control is set for one of broadcast transmission and multicast transmission, the UE may apply the setting to the other. As a result, the setting of retransmission control can be simplified.

< option 2>

The UE may determine whether to apply retransmission control for information transmitted by broadcast/multicast based on downlink control information (e.g., DCI). The base station may inform whether retransmission control is applied to each UE using UE-specific DCI, or may inform whether retransmission control is applied to each UE group using group-common DCI. For example, in the case where information transmitted through broadcast/multicast is scheduled by DCI, information on HARQ-ACK (e.g., information on whether at least one of application, transmission timing, and resources) may be included in the DCI.

When broadcast transmission and multicast transmission are separately supported, whether to apply retransmission control for broadcast transmission and whether to apply retransmission control for multicast transmission may be separately set. This makes it possible to flexibly control whether or not retransmission control is applied.

Alternatively, when broadcast transmission and multicast transmission are separately supported, whether or not retransmission control for broadcast transmission is applied and whether or not retransmission control for multicast transmission is applied may be set in common. In this case, if whether or not to apply retransmission control is set for one of broadcast transmission and multicast transmission, the UE may apply the setting to the other in the same manner. This can simplify the setting of retransmission control.

< option 3>

The UE may also implicitly decide whether to apply retransmission control for information transmitted over broadcast/multicast based on certain rules (implicit). The specific rule may be a specific condition set by transmission or reception (for example, a transmission condition used in broadcast/multicast transmission). Hereinafter, a case where the specific condition is the repeated transmission (case 1), and a case where the specific condition is at least one of the modulation and Coding scheme (mcs) and the Coding rate (case 2) will be described. The specific conditions are not limited to these.

[ case 1]

When retransmission is applied to information transmitted through broadcast/multicast, the UE may determine that retransmission control (e.g., HARQ) is not supported or not applied. Further, the UE may determine that retransmission control is supported or retransmission control is applied when repeated transmission is not applied.

The UE may determine whether to apply retransmission control based on the number of transmissions that are repeatedly transmitted (also referred to as an iteration factor). For example, the UE may not apply the retransmission control when the number of transmission times of the repeated transmission is equal to or greater than a specific value (for example, X), and may apply the retransmission control when the number of transmission times is not equal to or greater than the specific value. The specific value (e.g., X) may also be predefined in the specification, or may also be notified from the base station to the UE through higher layer signaling or the like.

Whether or not the iterative transmission is applied (or the number of times of the iterative transmission) may be set for each UE group. Alternatively, the iterative transmission (or the number of transmission times of the iterative transmission) may be set for each UE. In the case of setting for each UE, whether to apply retransmission control may be set independently for each UE included in the UE group.

[ case 2]

The UE may also determine whether to apply retransmission control for information transmitted by broadcast/multicast based on at least one of an MCS and a coding rate (hereinafter, also referred to as MCS/coding rate) applied to the information transmitted by broadcast/multicast.

For example, the UE may also apply no retransmission control in a case where the MCS/coding rate corresponding to the information transmitted through the broadcast/multicast is below a specific value (e.g., Y), and apply retransmission control in a case other than that (e.g., the MCS/coding rate is greater than the specific value). The specific value (e.g., Y) may be predefined in the specification, or may also be notified from the base station to the UE through higher layer signaling or the like.

In this way, by controlling whether or not to apply retransmission control for broadcast/multicast transmission based on a specific condition, retransmission control can be flexibly controlled based on a communication environment or communication conditions.

< HARQ Process >

In retransmission control by HARQ, retransmission control of data (transport block (TB) or Code Block (CB)) is performed in units of processes (HARQ processes). In the HARQ process of 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 HARQ process ID (HARQ process identifier).

In one time interval (e.g., slot or subframe), one HARQ process may be used, or multiple HARQ processes may be used. By independently processing a plurality of HARQ processes in parallel, it is possible to transmit data of a next HARQ process without waiting for a/N of a previous HARQ process, thereby reducing a delay time.

In retransmission control for broadcast/multicast transmission, retransmission control may be performed based on HARQ processes as well. For example, X (or X number, X number) (X ≧ 1) HARQ processes may be set for information transmitted by broadcast/multicast. X may be predefined in the specification, or may also be notified from the base station to the UE through at least one of higher layer signaling and downlink control information.

In the case where broadcast transmission and multicast transmission are separately supported, X for broadcast transmission and X for multicast transmission may also be separately set. X for broadcast transmission and X for multicast transmission may also be set in common. Alternatively, a different X may be set for each broadcast transmission (or each multicast transmission).

Further, it may be considered that the UE transmits HARQ-ACK for unicast transmission and HARQ-ACK for broadcast/multicast transmission (see FIG. 3). Fig. 3 shows an example in which the UE reports HARQ-ACK # B for broadcast/multicast transmission and HARQ-ACK # a for unicast transmission.

In this case, it is also possible to set (separate) a HARQ process pool (HARQ process pool) corresponding to information transmitted by unicast transmission and a HARQ process pool corresponding to information transmitted by broadcast/multicast. The pool of HARQ processes may be a processing operation of the HARQ process, or may also be a value of the HARQ process number or a range of HARQ process numbers.

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

In this way, by setting the HARQ process pool so as to distinguish between information transmitted by unicast and information transmitted by broadcast/multicast, it is possible to avoid collision between the HARQ process of unicast transmission and the HARQ process of broadcast/multicast transmission.

Alternatively, a HARQ process pool (HARQ process pool) corresponding to information transmitted by unicast transmission and a HARQ process pool corresponding to information transmitted by broadcast/multicast transmission may be set in a shared manner (share).

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

The network (e.g., base station) may also control HARQ process handling so that HARQ processes do not collide between information sent via unicast and information sent via broadcast/multicast. For example, at least one of the base station and the UE may control such that the HARQ process number allocated to one of the unicast transmission and the broadcast/multicast transmission is not allocated to the other.

Alternatively, priority (e.g., priority rule) may be set for the HARQ process, and when the HARQ process is duplicated, retransmission control may be performed based on the priority. For example, broadcast/multicast transmissions may also be given a higher priority than unicast transmissions. In the case where the HARQ process corresponding to the unicast transmission and the HARQ process corresponding to the broadcast/multicast transmission collide, the UE may preferentially perform retransmission control on the HARQ process corresponding to the broadcast/multicast transmission.

The priority of the HARQ process may also be set based on other conditions. For example, the priority of the HARQ process may also be decided based on the service (or traffic type). For example, the priority of the HARQ process corresponding to the first traffic type (e.g., URLLC) may be set higher than the priority of the HARQ process corresponding to the second traffic type (e.g., eMBB).

In addition, when the HARQ process number is 1(X is 1), the scheduling information may not include information for specifying the HARQ process number. For example, when X is 1, a field for HARQ process notification may be omitted in DCI scheduling at least one of control information and data transmitted by multicast/broadcast, and the DCI may be used for other purposes. In the other (X)>1) In this case, n bits (for example, n ═ log) may be set in the DCI₂(X)) field to inform a HARQ process ID corresponding to the multicast/broadcast transmission.

< Soft buffer >

The UE may also have a buffer (soft buffer) for temporarily storing the received data that failed decoding. In the soft buffer, received data (e.g., a TB, a code block, or a Code Block Group (CBG) containing more than one code block) may also be stored for each HPN.

The UE may soft-combine the received data (or retransmission data) based on the same HPN that is repeatedly transmitted. In addition, the user terminal may also soft-combine the data stored in the soft buffer with the received data of the same HPN. Soft combining is to assign the same HPN to a plurality of data generated from the same information bit sequence and transmit the data, and the receiver combines a plurality of data of the same HPN.

The soft buffer for information transmitted by unicast on the UE side and the soft buffer for information transmitted by broadcast/multicast on the UE side may be set in a shared manner. In this case, the soft buffer can be effectively used even in the case where decoding of one of the transmissions fails consecutively.

Alternatively, it is possible to distinguish (separate) the soft buffer set on the UE side for information transmitted by unicast and the soft buffer set on the UE side for information transmitted by broadcast/multicast. For example, in the UE, a soft buffer for broadcast/multicast transmission may be set in addition to a soft buffer used for unicast transmission. This prevents the soft buffer for one transmission from being affected by a failure in decoding of the other transmission.

(second mode)

The second embodiment describes feedback control of a transmission acknowledgement signal (also referred to as a retransmission control signal or HARQ-ACK) for broadcast/multicast transmission.

< HARQ-ACK Transmission timing >

The UE is at a specific timing (e.g., K)₁) HARQ-ACK for information transmitted through broadcast/multicast is fed back (see fig. 4). In fig. 4, it is shown that the UEs included in the UE group #1 are at a specific timing (e.g., K)₁₁、K₁₂) HARQ-ACK is fed back, and UEs included in the UE group #2 are at a specific timing (e.g., K)₂₁、K₂₂) And feeding back the HARQ-ACK.

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

[ option 2-1]

One timing value (one value) may be applied as transmission timing of HARQ-ACK for broadcast/multicast transmission. The one timing value may be defined in the specification, or may be notified from the base station to the UE through higher layer signaling or the like. The UE may alsoBased on the one timing value (e.g., fixed value K)₁) To decide the transmission timing of HARQ-ACK for broadcast/multicast transmission.

For example, in fig. 4, K may be used₁₁＝K₁₂＝K₂₁＝K₂₂Is a fixed value K₁. Alternatively, a timing value may be set for each UE group. For example, in FIG. 4, K may be₁₁＝K₁₂Is a fixed value K_A，K₂₁＝K₂₂Is a fixed value K_B。

The feedback timing of HARQ-ACK (e.g., the same value) may be set in common for a plurality of UEs included in a predetermined UE group that receives information transmitted by broadcast/multicast. For example, in FIG. 4, it may be at least K₁₁＝K₁₂、K₂₁＝K₂₂. Thus, the feedback timing of HARQ-ACK from a plurality of UEs included in a predetermined UE group can be aligned.

Alternatively, the feedback timing (e.g., different values) of HARQ-ACK may be set independently for each of a plurality of UEs included in the UE group. For example, in FIG. 4, it may be at least K₁₁≠K₁₂、K₂₁≠K₂₂. In this case, it is possible to disperse feedback timings of HARQ-ACKs from a plurality of UEs included in a specific UE group. In addition, the same value may be set for some of the plurality of UEs included in the specific group, and different values may be set for other UEs.

[ options 2-2]

A set of transmission timing values (or also referred to as a combination of transmission timing values, a plurality of transmission timing candidates, or a transmission timing candidate set) for HARQ-ACKs transmitted by broadcast/multicast may be set, and a specific transmission timing value may be selected from the set. The set of transmission timing values for HARQ-ACK may be defined in advance in the specification, or may be notified from the base station to the UE by using higher layer signaling or the like.

Further, the base station may also transmit information for specifying a specific transmission timing value from among the set of transmission timing values of HARQ-ACK to the UE. For example, the base station may include information for specifying a specific transmission timing value in the downlink control information and transmit the information to the UE. The UE may determine the transmission timing value of HARQ-ACK based on bit information included in the downlink control information.

Downlink control information (e.g., a group common PDCCH) may also be transmitted to a plurality of UEs (e.g., UEs included in a specific group). In this case, all UEs included in a specific group can feed back HARQ-ACKs with the same timing.

[ options 2-3]

The base station may also set a first transmission timing parameter (e.g., an offset (e.g., T _ delta or Δ T)) of the transmission timing of HARQ-ACK for each UE. For example, the base station may set the offset of the transmission timing of HARQ-ACK to the UE by using higher layer signaling or the like. In this case, an offset (e.g., a different offset) may be set separately for each UE, or an offset (e.g., an offset common to a specific group) may be set for each group.

Further, the base station may notify the UE of information on the second transmission timing parameter (for example, transmission timing of HARQ-ACK) using downlink control information or the like. For example, the base station may notify a plurality of UEs of the same transmission timing (for example, K) using DCI (or PDCCH) for scheduling broadcast/multicast transmission or DCI (or group-common PDCCH) common to groups₁). Alternatively, the base station may separately notify each UE of the transmission timing using the UE-specific DCI (or UE-specific PDCCH).

Each UE is based on a first transmission timing parameter (e.g., T _ delta) notified by higher layer signaling and a second transmission timing parameter (e.g., transmission timing K) notified by DCI₁) To determine the transmission timing (e.g., K) of HARQ-ACK₁+ T _ delta). Thus, by specifically notifying the UE of at least one of the first parameter and the second parameter (e.g., the offset), even in the case where the other is set to be common to the UE group, it is possible to flexibly control the transmission timing between the UEs.

In addition, the transmission timing of the HARQ-ACK for unicast transmission and the transmission timing of the HARQ-ACK for broadcast/multicast transmission may also be set separately (e.g., by using different methods). This makes it possible to flexibly control the feedback timing of HARQ-ACK according to each transmission.

< HARQ-ACK feedback resources >

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

[ option 3-1]

The base station may also notify each UE of information on the resource/format of a specific channel (e.g., PUCCH) used in HARQ-ACK transmission using higher layer signaling. The resource and format of the PUCCH to be notified to each UE may be set separately for each UE (for example, different resources and formats may be set).

Alternatively, the base station may notify information on the resource/format of the PUCCH used in HARQ-ACK transmission to each UE group using higher layer signaling. That is, the resources and formats of the PUCCH may be set in units of UE groups. In this case, the UEs included in the same group may also transmit HARQ-ACKs using the same resource/format.

In option 3-1, the UE can determine the resources/formats to be utilized in HARQ-ACK transmission based on the information notified through higher layer signaling (without utilizing L1 signaling).

[ options 3-2]

The base station may also inform each UE of the parameters of the first resource/format using higher layer signaling. The parameter of the first resource/format may also be information on a resource index (e.g., PUCCH _ index) of a specific channel (e.g., PUCCH) utilized in HARQ-ACK transmission. The resource index (e.g., different resource index) of the PUCCH may be set for each UE.

The base station may set a plurality of sets of PUCCH resources (also referred to as a plurality of PUCCH resource candidate sets) to the UE by higher layer signaling. Further, the base station may include information for specifying a specific set from among a plurality of sets in the downlink control information, and transmit the information to the UE. The particular set may also be referred to as a parameter of the second resource/format.

For example, the base station may also notify a specific set to a plurality of UEs using DCI (or PDCCH) for scheduling broadcast/multicast transmission or DCI common to groups (or PDCCH common to groups). Alternatively, the base station may separately notify each UE of a specific set using the UE-specific DCI (or UE-specific PDCCH).

Each UE may determine the PUCCH resource/format based on the parameter of the first resource/format notified by the higher layer signaling and the parameter of the second resource/format specified by at least one of DCI and the higher layer signaling. For example, the UE determines a PUCCH resource/format from a specific set of PUCCH resources specified by downlink control information based on a PUCCH resource index notified by higher layer signaling.

By specifically notifying the UE of at least one of the first resource/format parameter and the second resource/format parameter (e.g., PUCCH resource index), it is possible to utilize different PUCCH resources between UEs even if the other is set to be common to the UE group.

[ options 3-3]

The base station may set a plurality of PUCCH resources (also referred to as PUCCH resource candidates) to the UE by higher layer signaling. Further, the base station may transmit downlink control information including information for specifying a specific PUCCH resource from among the plurality of PUCCH resources to the UE (e.g., a plurality of UEs included in a specific group). The downlink control information may be DCI transmitted through a group common PDCCH, or may be DCI scheduling broadcast/multicast transmission.

In this case, the same PUCCH resource may be designated for a plurality of UEs included in a specific group.

(third mode)

A third embodiment describes transmission power control of an uplink channel (for example, at least one of PUCCH and PUSCH) used for transmission of HARQ-ACK for broadcast/multicast transmission. In the following description, PUCCH is described as an uplink channel used for transmission of HARQ-ACK, but other uplink channels (e.g., PUSCH) may be similarly applied.

< UL Transmission Power control >

In rel.15, the UE performs Transmission Power Control (TPC) for each transmission opportunity i. The transmission opportunity i may also be a transmission opportunity of a PUSCH, PUCCH, SRS, or PRACH. The transmission opportunity i may be set by a slot index n of (sub carrier spacing configuration) μ for a subcarrier spacing within a frame having a System Frame Number (SFN)_s,f ^μAnd the first symbol (index of the first symbol of transmission opportunity i) S in the slot, and the number of consecutive symbols L.

The transmission power of the PUCCH is controlled based on a TPC command (value, up-down value, correction value (correction value), indication value, or the like) indicated by the value of a specific field (also referred to as a TPC command field, first field, or the like) within the DCI.

For example, the transmission power (P) of the PUCCH in transmission opportunity (transmission opportunity) (also referred to as transmission period) I for the carrier f of the cell c using the index I of the power control adjustment state (power control adjustment state) is_PUCCH,b,f,c(I,q_u,q_dAnd I)), the compound can be represented by the following formula (1).

Here, the power control adjustment state may be set to have a plurality of states (for example, 2 states) or a single state by a higher layer parameter. Further, in the case where a plurality of power control adjustment states are set, one of the plurality of power control adjustment states may also be identified by an index I (e.g., I ∈ {0, 1 }). The power control adjustment state may also be referred to as a PUCCH power control adjustment state (PUCCH power control adjustment state), a first or second state, or the like.

The transmission opportunity i of the PUCCH is a specific period for transmitting the PUCCH, and may be configured by, for example, one or more symbols, one or more slots, or the like.

[ number 1]

Formula (1)

In formula (1), P_CMAX,f,c(i) For example, the transmission power of the user terminal set as the carrier f for transmitting the cell c in the opportunity i (also referred to as the maximum transmission power). P_{O_PUCCH,b,f,c}(q_u) For example, the parameter is a parameter related to the target reception power of the BWP b set to the carrier f for the cell c in the transmission opportunity i (for example, also referred to as a parameter related to the transmission power offset, the transmission power offset PO, or the target reception power parameter).

M^PUCCH _RB,b,f,c(i) For example, the number of resource blocks (bandwidth) allocated to the PUCCH for transmission opportunity i in uplink BWP b of cell c and carrier f at subcarrier spacing μ. PL_b,f,c(q_d) E.g. the index q of the reference signal used by the user terminal for the downlink BWP associated with the uplink BWP of carrier f of cell c_dThe calculated path loss.

Δ_{F_PUCCH}(F) Is a higher layer parameter assigned to each PUCCH format. Delta_TF,b,f,c(i) Is the transmit power adjustment component (offset) of the uplink BWP b for carrier f of cell c.

g_b,f,c(I, I) is the value of the TPC command (e.g., power control adjustment state, cumulative value of TPC command) based on the power control adjustment state index I of the uplink BWP of the carrier f of cell c and transmission opportunity I. For example, the cumulative value of the TPC command may also be expressed by a specific equation.

The TPC command may also be decided based on the value of a specific field (also referred to as a TPC command field, a first field, or the like) within DCI used for scheduling of a PUSCH or PDSCH. The power control information may also be referred to as TPC commands (also referred to as values, up-down values, correction values (correction values), etc.).

The formula (1) is merely an example, and is not limited thereto. The user terminal may include additional parameters or omit some of the parameters, as long as the user terminal controls the transmission power of the PUCCH based on at least one parameter exemplified by equation (1). In addition, in equation (1) above, the transmission power of the PUCCH is controlled for each BWP of a certain carrier of a certain cell, but is not limited thereto. At least a portion of the cell, carrier, BWP, power control adjustment state may also be omitted.

The UE applies a specific transmission power (or a specific transmission power parameter) to the PUCCH utilized in the feedback of the HARQ-ACK for the broadcast/multicast transmission (see fig. 5). In fig. 5, it is shown that the UEs included in the UE group #1 apply a specific transmission power (e.g., P)₁₁、P₁₂) The UE included in the UE group #2 feeds back HARQ-ACK by applying a specific transmission power (e.g., P)₂₁、P₂₂) The PUCCH of (2) feeds back HARQ-ACK.

The UE may also decide a specific transmission power based on specific information. For example, the UE may also apply any of the following options 4-1 to 4-2 to decide the transmission power.

[ option 4-1]

The UE may determine the transmission power of the PUCCH based on a parameter (also referred to as a transmission power parameter) set by higher layer signaling. The parameter set by the higher layer signaling may be a parameter (for example, a combination of P0 and α) included in the above expression (1), or may be another parameter.

Further, the transmission power parameter (for example, different transmission power parameter) may be set separately between a plurality of UEs included in a specific UE group to which the same information is transmitted by broadcast/multicast transmission. That is, the transmission power parameter may be set separately for each UE. For example, in FIG. 5, P is set separately₁₁And P₁₂(alternatively, P₂₁And P₂₂)。

Further, the transmission power value may be set separately between a plurality of UEs included in a specific UE group to which the same information is transmitted by broadcast/multicast transmission. This enables flexible control of transmission power control in consideration of interference between different UEs and the like.

[ options 4-2]

The base station may also set the first transmission power parameter for each UE using higher layer signaling. First transmission powerThe parameter may be set commonly for a plurality of UEs (e.g., a UE group) or may be set separately (e.g., different values) for each UE. The first transmit power parameter may be, for example, a power offset (e.g., P delta or P)_Δ)。

Further, the base station may also notify the UE of the second transmission power parameter using at least one of higher layer signaling and DCI. The second parameter may also be a power control value (e.g., P _ M or P)_M). For example, the base station may set a set of second transmission power parameters (e.g., a plurality of second parameter candidate values or a second parameter candidate set) to the UE using higher layer signaling, and notify the UE of the specific second parameters using DCI.

For example, the base station may also notify the specific second parameter to the plurality of UEs using DCI (or PDCCH) scheduling broadcast/multicast transmission or DCI (or group-common PDCCH) common to groups. Alternatively, the base station may separately notify each UE of the specific second parameter using the UE-specific DCI (or UE-specific PDCCH).

Each UE may also adjust the transmission power of the PUCCH based on the first transmission power parameter notified by the higher layer signaling and a second transmission power parameter (e.g., P _ delta + P _ M) specified by at least one of DCI and the higher layer signaling.

By specifically notifying at least one of the first transmission power parameter and the second transmission power parameter (e.g., P _ delta) to the UEs, it is possible to utilize different transmission powers among the UEs even in the case where the other is set to be common to the UE group.

[ options 4-3]

Each UE may also adjust the transmit power of the PUCCH based on the TPC command. For example, in addition to options 4-1 or 4-2, the UE may also consider the TPC command to determine the transmit power of the PUCCH.

The TPC command may also be included in the DCI scheduling the broadcast/multicast transmission. Alternatively, the TPC command may be included in another DCI different from the DCI scheduling the broadcast/multicast transmission. The DCI for transmitting the TPC command may be transmitted as UE-specific DCI, or may be transmitted as DCI common to a specific UE group (e.g., group-common PDCCH).

(fourth mode)

The fourth transmission illustrates transmission control of HARQ-ACK for broadcast/multicast transmission.

In HARQ-based retransmission control, the UE transmits ACK when a reception process (e.g., decoding) of data is successful, and transmits NACK when the reception process fails. As retransmission control for information transmitted through broadcast/multicast, the UE may also apply any one of the following options 5-1 to 5-2.

[ option 5-1]

The UE may also be controlled to report only one (e.g., NACK) as HARQ-ACK for broadcast/multicast transmission. For example, the UE may also control such that NACK is reported in the case where the decoding process for information transmitted through broadcast/multicast fails, and ACK is not reported in the case where the decoding process succeeds (see fig. 6).

Fig. 6 shows a case where NACK is transmitted when the UE included in the UE group #1 fails to decode the information transmitted by broadcast/multicast, and NACK is transmitted when the UE included in the UE group #2 fails to decode the information transmitted by broadcast/multicast. In addition, when the decoding is successful, the ACK may not be transmitted.

The base station may also determine that data reception is successful for a UE that does not report a NACK. NACK detection (detection) in the base station may also be power based detection (also called energy detection). For example, the base station may detect NACK by using the same mechanism as that for detecting a Scheduling Request (SR) transmitted through the PUCCH.

Further, the resource of NACK reported by each UE may be set (shared) in common among a plurality of UEs. That is, a UE transmitting NACK for broadcast/multicast transmission may also transmit NACK using the same UL channel resource (e.g., PUCCH resource). The resources for NACK reporting may be defined in the specification, or may be notified from the base station to each UE (or each UE group) by using at least one of downlink control information and higher layer signaling.

For example, in fig. 6, when a plurality of UEs included in the UE group #1 transmit NACK, NACK may be transmitted using the same UL channel resources (e.g., resources having the same time domain and frequency domain). Similarly, when a plurality of UEs included in the UE group #2 transmit NACK, NACK may be transmitted using the same UL channel resource (e.g., a resource having the same time domain and frequency domain).

In this way, by setting resources for NACK reporting in common to a plurality of UEs (for example, the same UE group), it is possible to improve the resource utilization efficiency.

The base station may also perform retransmission control (e.g., determine whether to retransmit) based on whether a NACK report is detected in the resources for NACK. For example, assume that the base station detects NACK in the resource set to UE group # 1. This means that at least one UE (UE transmitted through broadcast/multicast) in the UE group #1 fails decoding.

In this case, the base station may also retransmit the information (e.g., transport blocks) via broadcast/multicast transmission. The UE may control whether or not to receive the retransmitted information based on the reception status of the UE. For example, the UE that reported NACK receives the retransmitted information is controlled. On the other hand, a UE that does not report NACK (e.g., a successfully decoded UE) may also skip the reception process (e.g., decoding) of the retransmitted information.

In this way, by controlling whether to receive the retransmitted information based on the reception status, it is possible to suppress an increase in the load of the reception process of the UE.

In the above description, the case of reporting only NACK is shown, but the present invention is not limited to this. Only ACK may be transmitted.

[ options 5-2]

The UE may control such that only at least one of ACK and NACK is reported as HARQ-ACK for broadcast/multicast transmission. For example, the UE may perform control so that NACK is reported when decoding processing for information transmitted by broadcast/multicast fails, and ACK is reported when decoding processing succeeds. Alternatively, the UE may also control such that NACK is reported in the case where the decoding process fails, and ACK is not reported in the case where the decoding process succeeds, as in option 5-1 above.

The resources utilized by the UEs in the reporting of at least one of ACK and NACK (hereinafter, also referred to as ACK/NACK) may be separately set (e.g., UE-specific) for each UE (see fig. 7). In fig. 7, the following is shown: that is, each UE included in the UE group #1 transmits ACK/NACK for broadcast/multicast transmission using a different resource, and each UE included in the UE group #2 transmits ACK/NACK for broadcast/multicast transmission using a different resource. In addition, the UE may also report only NACKs (only in case of decoding failure).

In this way, different ACK/NACK reporting resources (for example, resources different in at least one of time domain, frequency domain, and code) may be set for a plurality of UEs belonging to the same UE group. The ACK/NACK reporting resource may be notified from the base station to each UE by using at least one of downlink control information and higher layer signaling.

The base station may perform retransmission control (for example, determine whether to retransmit) for each UE based on whether ACK/NACK is detected in the resource set for each UE. For example, the base station may retransmit only the UE that reported NACK. In this case, the base station may selectively retransmit retransmission information (e.g., transport blocks) for information transmitted by broadcast/multicast to a specific UE by unicast transmission.

This makes it possible to retransmit only the UE that failed to decode the information transmitted by broadcast/multicast. As a result, the UE that has successfully decoded does not need to receive the retransmitted information, and therefore, an increase in the load of the reception process of the UE can be suppressed.

The base station may determine the retransmission method according to the number of UEs that have transmitted NACK (or the number of UEs that have transmitted ACK). For example, if the UE that reported NACK is greater than or equal to a predetermined value (or the UE that reported ACK is less than a predetermined value), retransmission may also be performed by broadcast/multicast transmission. In this case, a UE that does not report NACK (or a UE that reports ACK) may also skip the reception process (e.g., decoding) of the retransmitted information.

(Wireless communication System)

Hereinafter, a configuration of a radio communication system according to an embodiment of the present disclosure will be described. In this radio communication system, communication is performed using any one of the radio communication methods according to the above embodiments of the present disclosure, or a combination thereof.

Fig. 8 is a diagram showing an example of a schematic configuration of a radio communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) standardized by the Third Generation Partnership Project (3GPP), a New Radio of the fifth Generation mobile communication system (5th Generation mobile communication system New Radio) (5G NR), or the like.

In addition, the wireless communication system 1 may also support Dual Connectivity (Multi-RAT Dual Connectivity (MR-DC)) between a plurality of Radio Access Technologies (RATs). The MR-DC may also include Dual connection of LTE (Evolved Universal Terrestrial Radio Access (E-UTRA))) with NR (E-UTRA-NR Dual connection (EN-DC))), Dual connection of NR with LTE (NR-E-UTRA Dual connection (NE-DC))), and the like.

In EN-DC, a base station (eNB) of LTE (E-UTRA) is a Master Node (MN), and a base station (gNB) of NR is a Slave Node (SN). In NE-DC, the base station of NR (gNB) is MN and the base station of LTE (E-UTRA) (eNB) is SN.

The wireless communication system 1 may also support Dual connection between a plurality of base stations within the same RAT (for example, Dual connection of a base station (gNB) in which both MN and SN are NR (NR-NR Dual Connectivity (NN-DC)))).

The wireless communication system 1 may include: a base station 11 forming a macro cell C1 having a relatively wide coverage area, and base stations 12(12a to 12C) arranged in the macro cell C1 and forming a small cell C2 narrower than the macro cell C1. The user terminal 20 may also be located in at least one cell. The arrangement, number, and the like of each cell and user terminal 20 are not limited to the embodiments shown in the figures. Hereinafter, the base stations 11 and 12 are collectively referred to as the base station 10 without distinguishing them.

The user terminal 20 may also be connected to at least one of the plurality of base stations 10. The user terminal 20 may use at least one of Carrier Aggregation (CA) and Dual Connectivity (DC) using a plurality of Component Carriers (CCs)).

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

The user terminal 20 may perform communication in each CC by using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD).

The plurality of base stations 10 may also be connected by wire (e.g., optical fiber based Common Public Radio Interface (CPRI)), X2 Interface, or the like) or wirelessly (e.g., NR communication). For example, when NR communication is used as a Backhaul between base stations 11 and 12, base station 11 corresponding to an upper station may be referred to as an Integrated Access Backhaul (IAB) donor (donor) and base station 12 corresponding to a relay (relay) may be referred to as an IAB node.

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

The user terminal 20 may be a terminal supporting at least one of communication schemes such as LTE, LTE-a, and 5G.

The radio communication system 1 may use a radio access scheme based on Orthogonal Frequency Division Multiplexing (OFDM). For example, in at least one of the downlink (dl)) and the uplink (ul)), Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used.

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

In the radio communication system 1, as the Downlink Channel, a Downlink Shared Channel (Physical Downlink Shared Channel (PDSCH))), a Broadcast Channel (Physical Broadcast Channel (PBCH))), a Downlink Control Channel (Physical Downlink Control Channel (PDCCH))) and the like that are Shared by the user terminals 20 may be used.

In the radio communication system 1, as the Uplink Channel, an Uplink Shared Channel (Physical Uplink Shared Channel (PUSCH))), an Uplink Control Channel (Physical Uplink Control Channel (PUCCH))), a Random Access Channel (Physical Random Access Channel (PRACH)), and the like, which are Shared by the user terminals 20, may be used.

User data, higher layer control Information, a System Information Block (SIB), and the like are transmitted through the PDSCH. User data, higher layer control information, etc. may also be transmitted over the PUSCH. In addition, a Master Information Block (MIB)) may also be transmitted through the PBCH.

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

The DCI scheduling PDSCH may be referred to as DL assignment, DL DCI, or the like, and the DCI scheduling PUSCH may be referred to as UL grant, UL DCI, or the like. In addition, PDSCH may be referred to as DL data instead, and PUSCH may be referred to as UL data instead.

For PDCCH detection, a COntrol REsource SET (countrol REsource SET (CORESET)) and a search space (search space) may be used. CORESET corresponds to searching for DCI resources. The search space corresponds to a search region and a search method of PDCCH candidates (PDCCH candidates). 1 CORESET may also be associated with 1 or more search spaces. The UE may also monitor the CORESET associated with a certain search space based on the search space settings.

One search space may also correspond to PDCCH candidates that conform to 1 or more aggregation levels (aggregation levels). The 1 or more search spaces may also be referred to as a set of search spaces. In addition, "search space", "search space set", "search space setting", "search space set setting", "CORESET setting", and the like of the present disclosure may be referred to interchangeably.

Uplink Control Information (UCI)) including at least one of Channel State Information (CSI), ACKnowledgement Information (for example, Hybrid Automatic Repeat Request (HARQ-ACK), ACK/NACK, and the like, which may also be referred to as a Scheduling Request (SR)) may also be transmitted through the PUCCH.

In addition, in the present disclosure, a downlink, an uplink, and the like may also be expressed without "link". Further, it can be said that "Physical (Physical)" is not attached to the head of each channel.

In the wireless communication system 1, a Synchronization Signal (SS), a Downlink Reference Signal (DL-RS), and the like may be transmitted. In the wireless communication system 1, the DL-RS may be a Cell-specific Reference Signal (CRS), a Channel State Information Reference Signal (CSI-RS), a DeModulation Reference Signal (DMRS), a Positioning Reference Signal (PRS), a Phase Tracking Reference Signal (PTRS), or the like.

The Synchronization Signal may be at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS), for example. The signal blocks containing SS (PSS, SSs) and PBCH (and DMRS for PBCH) may also be referred to as SS/PBCH blocks, SS blocks (SSB)), etc. In addition, SS, SSB, etc. may also be referred to as reference signals.

In addition, in the wireless communication system 1, as an Uplink Reference Signal (UL-RS), a measurement Reference Signal (Sounding Reference Signal (SRS)), a demodulation Reference Signal (DMRS), or the like may be transmitted. The DMRS may also be referred to as a user terminal specific Reference Signal (UE-specific Reference Signal).

(base station)

Fig. 9 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transmitting/receiving unit 120, a transmitting/receiving antenna 130, and a transmission line interface (transmission line interface) 140. The control unit 110, the transmission/reception unit 120, the transmission/reception antenna 130, and the transmission line interface 140 may be provided in one or more numbers.

In this example, the functional blocks of the characteristic parts in the present embodiment are mainly shown, but it is also conceivable that the base station 10 further has other functional blocks necessary for wireless communication. A part of the processing of each unit described below may be omitted.

The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured by a controller, a control circuit, and the like described based on common knowledge in the technical field of the present disclosure.

The control unit 110 may also control generation of signals, scheduling (e.g., resource allocation, mapping), and the like. The control unit 110 may control transmission and reception, measurement, and the like using the transmission and reception unit 120, the transmission and reception antenna 130, and the transmission path interface 140. Control section 110 may generate data, control information, sequence (sequence), and the like to be transmitted as a signal, and forward the generated data, control information, sequence, and the like to transmission/reception section 120. The control unit 110 may perform call processing (setting, release, and the like) of a communication channel, state management of the base station 10, management of radio resources, and the like.

The transceiver 120 may also include a baseband (baseband) unit 121, a Radio Frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may also include a transmission processing unit 1211 and a reception processing unit 1212. The transmission/reception section 120 can be configured by a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter (phase shifter), a measurement circuit, a transmission/reception circuit, and the like, which are described based on common knowledge in the technical field of the present disclosure.

The transmission/reception unit 120 may be configured as an integrated transmission/reception unit, or may be configured by a transmission unit and a reception unit. The transmission unit may be constituted by the transmission processing unit 1211 and the RF unit 122. The receiving unit may be configured by the reception processing unit 1212, the RF unit 122, and the measurement unit 123.

The transmitting/receiving antenna 130 can be configured by an antenna described based on common knowledge in the technical field of the present disclosure, for example, an array antenna.

The transmitting/receiving unit 120 may transmit the above-described downlink channel, synchronization signal, downlink reference signal, and the like. The transmission/reception unit 120 may receive the uplink channel, the uplink reference signal, and the like.

Transmit/receive section 120 may form at least one of a transmit beam and a receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), and the like.

For example, with respect to Data, Control information, and the like acquired from Control section 110, transmission/reception section 120 (transmission processing section 1211) may perform processing of a Packet Data Convergence Protocol (PDCP) layer, processing of a Radio Link Control (RLC) layer (e.g., RLC retransmission Control), processing of a Medium Access Control (MAC) layer (e.g., HARQ retransmission Control), and the like, and generate a bit string to be transmitted.

Transmission/reception section 120 (transmission processing section 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filter processing, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-analog conversion on a bit sequence to be transmitted, and output a baseband signal.

The transmission/reception unit 120(RF unit 122) may perform modulation, filter processing, amplification, and the like for a baseband signal in a radio frequency band, and transmit a signal in the radio frequency band via the transmission/reception antenna 130.

On the other hand, the transmission/reception unit 120(RF unit 122) may amplify, filter, demodulate a baseband signal, and the like, a signal of a radio frequency band received through the transmission/reception antenna 130.

Transmission/reception section 120 (reception processing section 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filter processing, demapping, demodulation, decoding (may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data.

The transmission/reception unit 120 (measurement unit 123) may also perform measurement related to the received signal. For example, measurement section 123 may perform Radio Resource Management (RRM) measurement, Channel State Information (CSI) measurement, and the like based on the received signal. Measurement section 123 may measure reception Power (e.g., Reference Signal Received Power (RSRP)), reception Quality (e.g., Reference Signal Received Quality (RSRQ)), Signal to Interference plus Noise Ratio (SINR)), Signal to Noise Ratio (SNR)), Signal Strength Indicator (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), and the like. The measurement result may also be output to the control unit 110.

The transmission path interface 140 may transmit and receive signals (backhaul signaling) to and from devices included in the core network 30, other base stations 10, and the like, or may acquire and transmit user data (user plane data) and control plane data and the like for the user terminal 20.

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

In addition, the transmission reception unit 120 transmits the specific information by using at least one of broadcasting and multicasting. Transmission/reception section 120 may also receive retransmission control information for specific information transmitted by at least one of broadcasting and multicasting.

Control section 110 may also perform control so as to set whether or not to apply retransmission control for specific information transmitted by at least one of broadcast and multicast to the UE.

Further, control section 110 may control the UE to set transmission timing for retransmission control of specific information transmitted by at least one of broadcast and multicast.

Further, control section 110 may also control so that the transmission power for retransmission control of specific information transmitted by using at least one of broadcasting and multicasting is set to the UE.

Further, control section 110 may control the UE to set resources for retransmission control of specific information transmitted by at least one of broadcast and multicast.

(user terminal)

Fig. 10 is a diagram showing an example of a configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transmission/reception unit 220, and a transmission/reception antenna 230. Further, the control unit 210, the transmission/reception unit 220, and the transmission/reception antenna 230 may be provided with one or more antennas.

In this example, the functional blocks of the characteristic parts in the present embodiment are mainly shown, but it is also conceivable that the user terminal 20 further has other functional blocks necessary for wireless communication. A part of the processing of each unit described below may be omitted.

The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured by a controller, a control circuit, and the like described based on common knowledge in the technical field of the present disclosure.

The control unit 210 may also control the generation, mapping, etc. of the signals. Control section 210 may control transmission/reception, measurement, and the like using transmission/reception section 220 and transmission/reception antenna 230. Control section 210 may generate data, control information, a sequence, and the like to be transmitted as a signal, and forward the generated data, control information, sequence, and the like to transmission/reception section 220.

The transceiver unit 220 may also include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband section 221 may include a transmission processing section 2211 and a reception processing section 2212. The transmitting/receiving section 220 can be configured by a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transmitting/receiving circuit, and the like, which are described based on common knowledge in the technical field of the present disclosure.

The transmission/reception unit 220 may be configured as an integrated transmission/reception unit, or may be configured by a transmission unit and a reception unit. The transmission section may be constituted by the transmission processing section 2211 and the RF section 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measuring unit 223.

The transmission/reception antenna 230 can be configured by an antenna described based on common knowledge in the technical field of the present disclosure, for example, an array antenna.

The transmitting/receiving unit 220 may receive the downlink channel, the synchronization signal, the downlink reference signal, and the like. The transmission/reception unit 220 may transmit the uplink channel, the uplink reference signal, and the like described above.

Transmit/receive section 220 may form at least one of a transmit beam and a receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), and the like.

For example, transmission/reception section 220 (transmission processing section 2211) may perform processing in the PDCP layer, processing in the RLC layer (for example, RLC retransmission control), processing in the MAC layer (for example, HARQ retransmission control), and the like on data, control information, and the like acquired from control section 210, and generate a bit sequence to be transmitted.

Transmission/reception section 220 (transmission processing section 2211) may perform transmission processing such as channel coding (including error correction coding as well), modulation, mapping, filter processing, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on a bit sequence to be transmitted, and output a baseband signal.

In addition, whether or not the DFT processing is applied may also be based on the setting of transform precoding. For a certain channel (e.g., PUSCH), when transform precoding is active (enabled), transmission/reception section 220 (transmission processing section 2211) may perform DFT processing as the transmission processing in order to transmit the channel using a DFT-s-OFDM waveform, or otherwise, transmission/reception section 220 (transmission processing section 2211) may not perform DFT processing as the transmission processing.

The transmission/reception section 220(RF section 222) may perform modulation, filtering, amplification, and the like for a baseband signal in a radio frequency band, and transmit a signal in the radio frequency band via the transmission/reception antenna 230.

On the other hand, the transmission/reception section 220(RF section 222) may perform amplification, filter processing, demodulation to a baseband signal, and the like on a signal in a radio frequency band received by the transmission/reception antenna 230.

Transmission/reception section 220 (reception processing section 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filter processing, demapping, demodulation, decoding (including error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data.

The transceiver unit 220 (measurement unit 223) may also perform measurements related to the received signal. For example, the measurement unit 223 may also perform RRM measurement, CSI measurement, and the like based on the received signal. Measurement unit 223 may also measure for received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), and the like. The measurement result may also be output to the control unit 210.

The transmitting unit and the receiving unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting/receiving unit 220 and the transmitting/receiving antenna 230.

In addition, the transmission reception unit 220 receives specific information transmitted through at least one of broadcasting and multicasting. Further, the transmission reception unit 220 may transmit retransmission control information for specific information transmitted through at least one of broadcasting and multicasting.

Control section 210 may also determine whether or not to transmit retransmission control information for specific information based on at least one of information transmitted from the network and a condition applied to transmission of the specific information. For example, control section 210 may determine whether to transmit retransmission control information for specific information based on at least one of whether to apply repeated transmission for the specific information, an MCS applied for the specific information, and a coding rate applied for the specific information. It is also conceivable that control section 210 is set in common with the process number used for retransmission control for specific information and the process number used for retransmission control for information transmitted by unicast. Further, control section 210 may assume that a process number used for retransmission control for specific information and a process number used for retransmission control for information transmitted by unicast are set separately.

Control section 210 may determine the transmission timing of retransmission control information for specific information based on at least one of a predefined value and information transmitted from the network. Further, control section 210 may select a specific transmission timing based on information on a candidate set of transmission timings of retransmission control information for specific information and downlink control information transmitted in common to a specific user terminal. Further, control section 210 may determine the transmission timing of information for retransmission control of specific information based on the first transmission timing parameter notified by higher layer signaling and the second transmission timing parameter notified by downlink control information. Furthermore, control section 210 may determine a resource to be used for transmission of retransmission control information for specific information based on a first resource parameter notified by higher layer signaling and a second resource parameter specified by at least one of higher layer signaling and downlink control information. Further, control section 210 may select a specific resource based on a candidate set of resources used for transmission of retransmission control information for specific information and downlink control information that is commonly transmitted to a specific user terminal.

Control section 210 may determine the transmission power of the uplink channel to be used for transmission of retransmission control information for specific information based on the transmission power parameter reported to each user terminal. It is also conceivable that control section 210 separately sets at least one of the value of the transmission power parameter and the transmission timing of the retransmission control information for each user terminal. Control section 210 may determine the transmission power based on a first transmission power parameter notified by higher layer signaling and a second transmission power parameter specified by at least one of higher layer signaling and downlink control information. Control section 210 may determine the transmission power based on a transmission power control command included in downlink control information different from the downlink control information used for scheduling specific information.

The control unit 210 may also control reporting of retransmission control information for specific information using resources commonly set among a plurality of user terminals. Further, control section 210 may also perform control so that only one of ACK and NACK is reported as retransmission control information. Further, when retransmission of specific information is transmitted by broadcast or multicast, control section 210 may determine whether to receive the retransmitted information based on the reception result of the specific information. Further, control section 210 may control reporting of retransmission control information for specific information using resources separately provided between user terminals. Control section 210 may also assume that retransmission of specific information is transmitted by unicast.

(hardware construction)

The block diagram used in the description of the above embodiment shows blocks in functional units. These functional blocks (structural units) are implemented by any combination of at least one of hardware and software. The method of implementing each functional block is not particularly limited. That is, each functional block may be implemented by one apparatus that is physically or logically combined, or may be implemented by a plurality of apparatuses that are directly or indirectly (for example, by wire or wireless) connected to two or more apparatuses that are physically or logically separated. The functional blocks may also be implemented by combining the above-described apparatus or apparatuses with software.

Here, the functions include judgment, determination, judgment, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, establishment, comparison, assumption, expectation, view, broadcast (broadcasting), notification (notification), communication (communicating), forwarding (forwarding), configuration (configuring), reconfiguration (reconfiguration), allocation (mapping), assignment (assigning), etc., but the functions are not limited to these. For example, a function block (a configuration unit) that realizes a transmission function may also be referred to as a transmission unit (transmitting unit), a transmitter (transmitter), or the like. Any of these methods is not particularly limited, as described above.

For example, the base station, the user terminal, and the like in one embodiment of the present disclosure may also function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 11 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment. The base station 10 and the user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the present disclosure, terms such as device, circuit, device, section (section), and unit can be referred to each other. The hardware configurations of the base station 10 and the user terminal 20 may include one or more of the respective devices shown in the drawings, or may not include some of the devices.

For example, only one processor 1001 is illustrated, but there may be multiple processors. The processing may be executed by one processor, or may be executed by two or more processors simultaneously, sequentially, or in another manner. Further, the processor 1001 may be implemented by one or more chips.

Each function of the base station 10 and the user terminal 20 is realized by, for example, reading specific software (program) into hardware such as the processor 1001 and the memory 1002, performing an operation by the processor 1001 to control communication via the communication device 1004, or controlling at least one of reading and writing of data in the memory 1002 and the storage 1003.

The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be configured by a Central Processing Unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, a register, and the like. For example, at least a part of the control unit 110(210), the transmitting and receiving unit 120(220), and the like may be implemented by the processor 1001.

Further, the processor 1001 reads out a program (program code), a software module, data, and the like from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and executes various processes according to them. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiments can be used. For example, the control unit 110(210) may be realized by a control program stored in the memory 1002 and operated by the processor 1001, and may be similarly realized for other functional blocks.

The Memory 1002 may be a computer-readable recording medium, and may be configured by at least one of a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically Erasable Programmable ROM (EEPROM)), a Random Access Memory (RAM), or another suitable storage medium. The memory 1002 may also be referred to as a register, cache, main memory (primary storage), or the like. The memory 1002 can store a program (program code), a software module, and the like that are executable to implement the wireless communication method according to one embodiment of the present disclosure.

The storage 1003 may be a computer-readable recording medium, and may be configured by at least one of a flexible disk (flexible Disc), a Floppy (registered trademark) disk, an optical disk (e.g., a Compact Disc read only memory (CD-ROM)) or the like), a digital versatile Disc (dvd), a Blu-ray (registered trademark) disk, a removable disk (removable Disc), a hard disk drive, a smart card (smart card), a flash memory device (e.g., a card (card), a stick (stick), a key drive), a magnetic stripe (stripe), a database, a server, or other suitable storage medium, for example.

The communication device 1004 is hardware (transmission/reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, a network controller, a network card, a communication module, or the like. Communication apparatus 1004 may be configured to include a high-Frequency switch, a duplexer, a filter, a Frequency synthesizer, and the like, in order to realize at least one of Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD), for example. For example, the transmitting/receiving unit 120(220), the transmitting/receiving antenna 130(230), and the like described above may be implemented by the communication device 1004. The transmitting/receiving unit 120(220) may be physically or logically separately installed from the transmitting unit 120a (220a) and the receiving unit 120b (220 b).

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, and the like) that receives an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, a Light Emitting Diode (LED) lamp, or the like) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated (for example, a touch panel).

Further, the processor 1001, the memory 1002, and other devices are connected by a bus 1007 for communicating information. The bus 1007 may be formed by a single bus, or may be formed by different buses between the respective devices.

The base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), a Field Programmable Gate Array (FPGA), or the like, and a part or all of the functional blocks may be implemented by the hardware. For example, the processor 1001 may also be installed with at least one of these hardware.

(modification example)

In addition, terms described in the present disclosure and terms required for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, channels, symbols, and signals (signals or signaling) may also be referred to interchangeably. Further, the signal may also be a message. The Reference Signal (Reference Signal) may also be referred to as RS for short, and may also be referred to as Pilot (Pilot), Pilot Signal, etc. depending on the applied standard. Further, Component Carriers (CCs) may also be referred to as cells, frequency carriers, Carrier frequencies, and the like.

A radio frame may also be composed of one or more periods (frames) in the time domain. The one or more periods (frames) constituting a radio frame may also be referred to as subframes. Further, a subframe may also be composed of one or more slots in the time domain. The subframe may also be a fixed time length (e.g., 1ms) independent of a parameter set (numerology).

Here, the parameter set may also refer to a communication parameter applied in at least one of transmission and reception of a certain signal or channel. For example, the parameter set may indicate at least one of SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), the number of symbols per TTI, radio frame structure, specific filtering processing performed by the transceiver in the frequency domain, specific windowing processing performed by the transceiver in the Time domain, and the like.

The time slot may be formed of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM)) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, or the like) in the time domain. Further, the time slot may also be a time unit based on a parameter set.

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

The radio frame, subframe, slot, mini-slot, and symbol all represent a unit of time when a signal is transmitted. The radio frame, subframe, slot, mini-slot, and symbol may also use other names corresponding to each. In addition, time units such as frames, subframes, slots, mini-slots, symbols, etc. in the present disclosure may be referred to each other.

For example, one subframe may also be referred to as TTI, a plurality of consecutive subframes may also be referred to as TTI, and one slot or one mini-slot may also be referred to as TTI. That is, at least one of the subframe and TTI may be a subframe (1ms) in the conventional LTE, may be a period shorter than 1ms (for example, 1 to 13 symbols), or may be a period longer than 1 ms. The unit indicating TTI may be referred to as a slot, a mini slot, or the like, instead of a subframe.

Here, the TTI refers to, for example, the minimum time unit of scheduling in wireless communication. For example, in the LTE system, the base station performs scheduling for allocating radio resources (such as a frequency bandwidth and transmission power usable by each user terminal) to each user terminal in TTI units. In addition, the definition of TTI is not limited thereto.

The TTI may be a transmission time unit of a channel-coded data packet (transport block), code block, code word, or the like, or may be a processing unit of scheduling, link adaptation, or the like. In addition, when a TTI is given, a time interval (e.g., the number of symbols) to which a transport block, a code block, a codeword, etc. are actually mapped may also be shorter than the TTI.

When one slot or one mini-slot is referred to as a TTI, one or more TTIs (i.e., one or more slots or one or more mini-slots) may be the minimum time unit for scheduling. The number of slots (the number of mini-slots) constituting the minimum time unit of the schedule may be controlled.

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

Further, a long TTI (e.g., a normal TTI, a subframe, etc.) may be changed to a TTI having a time length exceeding 1ms, and a short TTI (e.g., a shortened TTI, etc.) may be changed to a TTI having a TTI length smaller than the long TTI and equal to or longer than 1 ms.

A Resource Block (RB) is a Resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the parameter set, and may be 12, for example. The number of subcarriers included in the RB may also be decided based on the parameter set.

In addition, an RB may include one or more symbols in the time domain, and may have a length of one slot, one mini-slot, one subframe, or one TTI. One TTI, one subframe, and the like may be formed of one or more resource blocks.

In addition, one or more RBs may also be referred to as a Physical Resource Block (PRB), a subcarrier Group (SCG), a Resource Element Group (REG), a PRB pair, an RB pair, and the like.

Furthermore, a Resource block may also be composed of one or more Resource Elements (REs). For example, one RE may also be a radio resource region of one subcarrier and one symbol.

The Bandwidth Part (BWP) (which may be referred to as a partial Bandwidth) may also indicate a subset of consecutive common RBs (common resource blocks) for a certain parameter set in a certain carrier. Here, the common RB may also be determined by an index of an RB with reference to a common reference point of the carrier. PRBs may also be defined in a certain BWP and are numbered additionally within the BWP.

The BWP may include UL BWP (UL BWP) and DL BWP (DL BWP). For the UE, one or more BWPs may also be set within 1 carrier.

At least one of the set BWPs may be active, and the UE may not expect to transmit and receive a specific signal/channel other than the active BWP. In addition, "cell", "carrier", and the like in the present disclosure may also be referred to as "BWP" instead.

The above-described configurations of radio frames, subframes, slots, mini slots, symbols, and the like are merely examples. For example, the structure of the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of mini-slots included in a slot, the number of symbols and RBs included in a slot or mini-slot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the Cyclic Prefix (CP) length, and the like can be variously changed.

The information, parameters, and the like described in the present disclosure may be expressed as absolute values, relative values to specific values, or other corresponding information. For example, the radio resource may also be indicated by a specific index.

In the present disclosure, the names used for the parameters and the like are not limitative names in all aspects. Further, the mathematical expressions and the like using these parameters may also be different from those explicitly disclosed in the present disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable names, and thus, the various names assigned to these various channels and information elements are not limitative names in all aspects.

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

Information, signals, and the like can be output in at least one direction from a higher layer (upper layer) to a lower layer (lower layer) and from the lower layer to the higher layer. Information, signals, and the like may be input and output via a plurality of network nodes.

The input/output information, signals, and the like may be stored in a specific location (for example, a memory) or may be managed by a management table. The inputted and outputted information, signals, etc. may be overwritten, updated or appended. The output information, signals, etc. may also be deleted. The input information, signals, etc. may also be transmitted to other devices.

The information notification is not limited to the embodiment and embodiment described in the present disclosure, and may be performed by other methods. For example, the Information notification in the present disclosure may be implemented by physical layer signaling (e.g., Downlink Control Information (DCI)), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC)) signaling, broadcast Information (Master Information Block (MIB)), System Information Block (SIB)), or the like), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

The physical Layer signaling may also be referred to as Layer 1/Layer 2(L1/L2)) control information (L1/L2 control signal), L1 control information (L1 control signal), and the like. The RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup (RRC Connection Setup) message, an RRC Connection Reconfiguration (RRC Connection Reconfiguration) message, or the like. The MAC signaling may be notified using a MAC Control Element (CE), for example.

Note that the notification of the specific information (for example, the notification of "X") is not limited to an explicit notification, and may be performed implicitly (for example, by not performing the notification of the specific information or by performing the notification of other information).

The determination may be performed by a value (0 or 1) represented by one bit, by a true-false value (boolean value) represented by true (true) or false (false), or by a comparison of values (for example, a comparison with a predetermined value).

Software, whether referred to as software (software), firmware (firmware), middleware-ware (middle-ware), microcode (micro-code), hardware description language, or by other names, should be broadly construed to mean instructions, instruction sets, code (code), code segments (code segments), program code (program code), programs (program), subroutines (sub-program), software modules (software module), applications (application), software applications (software application), software packages (software packages), routines (routine), subroutines (sub-routine), objects (object), executables, threads of execution, processes, functions, or the like.

Software, instructions, information, and the like may also be transmitted or received via a transmission medium. For example, where the software is transmitted from a website, server, or other remote source (remote source) using at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), etc.) and wireless technology (infrared, microwave, etc.), at least one of these wired and wireless technologies is included within the definition of transmission medium.

The terms "system" and "network" as used in this disclosure can be used interchangeably. "network" may also mean a device (e.g., a base station) included in a network.

In the present disclosure, terms such as "precoding", "precoder", "weight", "Quasi-Co-location (qcl)", "Transmission Configuration Indication state (TCI state)", "spatial relationship (spatial relationship)", "spatial filter (spatial domain filter)", "Transmission power", "phase rotation", "antenna port group", "layer", "rank", "resource set", "resource group", "beam width", "beam angle", "antenna element", "panel", and the like can be used interchangeably.

In the present disclosure, terms such as "Base Station (BS)", "wireless Base Station", "fixed Station (fixed Station)", "NodeB", "enb (enodeb)", "gnb (gtnodeb)", "access point (access point)", "Transmission Point (TP)", "Reception Point (RP)", "Transmission Reception Point (TRP)", "panel", "cell", "sector", "cell group", "carrier", "component carrier" can be used interchangeably. There are also cases where a base station is referred to by terms such as macrocell, smallcell, femtocell, picocell, and the like.

The base station can accommodate one or more (e.g., three) cells. When a base station accommodates a plurality of cells, the entire coverage area of the base station can be divided into a plurality of smaller areas, and each smaller area can also provide communication services through a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a portion or the entirety of the coverage area of at least one of a base station and a base station subsystem that is in communication service within the coverage area.

In the present disclosure, terms such as "Mobile Station (MS)", "User terminal (User terminal)", "User Equipment (UE)))," terminal "and the like can be used interchangeably.

In some instances, a mobile station is also referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset (hand set), user agent, mobile client, or some other suitable terminology.

At least one of the base station and the mobile station may also be referred to as a transmitting apparatus, a receiving apparatus, a wireless communication apparatus, and the like. At least one of the base station and the mobile station may be an apparatus mounted on a mobile body, the mobile body itself, or the like. The mobile body may be a vehicle (e.g., an automobile, an airplane, etc.), may be a mobile body that moves in an unmanned manner (e.g., a drone (a drone), an autonomous vehicle, etc.), or may be a robot (manned or unmanned). At least one of the base station and the mobile station further includes a device that does not necessarily move when performing a communication operation. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

In addition, the base station in the present disclosure may also be referred to as a user terminal instead. For example, the various aspects/embodiments of the present disclosure may also be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between a plurality of user terminals (e.g., may also be referred to as Device-to-Device (D2D)), Vehicle networking (V2X), etc.). In this case, the user terminal 20 may have the functions of the base station 10 described above. The expressions such as "uplink" and "downlink" may be referred to as expressions (for example, "side") corresponding to inter-terminal communication instead. For example, the uplink channel, the downlink channel, etc. may be referred to as a side channel instead.

Likewise, a user terminal in the present disclosure may also be referred to as a base station instead. In this case, the base station 10 may have the functions of the user terminal 20 described above.

In the present disclosure, it is assumed that the operation performed by the base station is also performed by an upper node (upper node) thereof depending on the case. Obviously, in a network including one or more network nodes (network nodes) having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (for example, considering a Mobility Management Entity (MME), a Serving-Gateway (S-GW)), and the like, but not limited thereto), or a combination thereof.

The embodiments and modes described in the present disclosure may be used alone, may be used in combination, or may be switched to use with execution. Note that, in the embodiments and the embodiments described in the present disclosure, the order of the processes, sequences, flowcharts, and the like may be changed as long as they are not contradictory. For example, elements of various steps are presented in an exemplary order for a method described in the present disclosure, but the present invention is not limited to the specific order presented.

The aspects/embodiments described in the present disclosure may also be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-a), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, fourth generation Mobile communication System (4G)), fifth generation Mobile communication System (5G)), Future Radio Access (FRA), New Radio Access Technology (RAT)), New Radio (New Radio trademark (NR)), New Radio Access (NX)), New Radio Access (Future Radio Access), FX), Global Broadband communication System (Global System for Mobile communication (GSM for Mobile), Mobile Broadband Mobile communication System (GSM) and Mobile telecommunications (CDMA) registration (2000 Mobile communication System))), IEEE 802.11(Wi-Fi (registered trademark)), IEEE 802.16(WiMAX (registered trademark)), IEEE 802.20, Ultra-wideband (uwb), Bluetooth (registered trademark), a system using another appropriate wireless communication method, a next generation system expanded based on these, and the like. Furthermore, multiple systems may also be applied in combination (e.g., LTE or LTE-a, combination with 5G, etc.).

The term "based on" used in the present disclosure does not mean "based only" unless otherwise specified. In other words, the expression "based on" means both "based only on" and "based at least on".

Any reference to the use of the terms "first," "second," etc. in this disclosure does not fully define the amount or order of such elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, reference to first and second elements does not imply that only two elements may be used or that the first element must somehow override the second element.

The term "determining" used in the present disclosure includes various operations in some cases. For example, "determination (decision)" may be regarded as a case where "determination (decision)" is performed on determination (rounding), calculation (calculating), processing (processing), derivation (deriving), investigation (investigating), search (looking up), search, inquiry (query)) (for example, search in a table, a database, or another data structure), confirmation (authenticating), and the like.

The "determination (decision)" may be regarded as a case of "determining (deciding)" on reception (e.g., reception information), transmission (e.g., transmission information), input (input), output (output), access (e.g., access to data in a memory), and the like.

The "determination (decision)" may be also regarded as a case of performing "determination (decision)" on solution (resolving), selection (selecting), selection (breathing), establishment (evaluating), comparison (comparing), and the like. That is, the "judgment (decision)" may also be regarded as a case where the "judgment (decision)" is made for some operations.

The "judgment (determination)" may be referred to as "assumption", "expectation", "consideration", and the like.

The "maximum transmission power" described in the present disclosure may mean a maximum value of transmission power, may mean a nominal maximum transmission power (the nominal UE maximum transmission power), and may mean a nominal maximum transmission power (the rated UE maximum transmission power).

The terms "connected" and "coupled" or any variation thereof used in the present disclosure mean all connections or couplings between two or more elements directly or indirectly, and can include a case where one or more intermediate elements exist between two elements "connected" or "coupled" to each other. The combination or connection between the elements may be physical, logical, or a combination of these. For example, "connected" may also be referred to as "accessed" instead.

In the present disclosure, when two elements are connected, it can be considered that the two elements are "connected" or "coupled" to each other using one or more electric wires, cables, printed electrical connections, and the like, and using electromagnetic energy having a wavelength in a radio frequency domain, a microwave domain, a light (both visible and invisible) domain, and the like as a few non-limiting and non-inclusive examples.

In the present disclosure, the term "a is different from B" may mean "a and B are different from each other". In addition, the term may also mean "a and B are different from C, respectively". The terms "separate", "associated", and the like may likewise be construed as "different".

In the present disclosure, when the terms "including", and variations thereof are used, these terms mean an inclusive meaning as with the term "comprising". Further, the term "or" used in the present disclosure does not mean exclusive or.

In the present disclosure, where articles are attached by translation, for example, as in a, an, and the in english, the present disclosure may also include the case where nouns following the articles are plural.

Although the invention according to the present disclosure has been described in detail above, it will be apparent to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented as modifications and variations without departing from the spirit and scope of the invention defined by the claims. Therefore, the description of the present disclosure is for illustrative purposes and does not have any limiting meaning to the invention to which the present disclosure relates.

The application is based on the patent application No. 2019-094080 filed on 5, 17.2019. All of which are incorporated herein.

Claims (6)

1. A user terminal, comprising:

a receiving unit that receives specific information transmitted by at least one of broadcasting and multicasting; and

and a control unit configured to control reporting of retransmission control information for the specific information by using a resource commonly set among the plurality of user terminals.

2. The user terminal of claim 1,

the control unit controls such that only one of ACK and NACK is reported as the retransmission control information.

3. The user terminal according to claim 1 or 2,

in a case where retransmission of the specific information is transmitted by broadcasting and multicasting, the control unit decides whether to receive the retransmitted information based on a reception result of the specific information.

4. A user terminal, comprising:

a receiving unit that receives specific information transmitted by at least one of broadcasting and multicasting; and

and a control unit configured to control reporting of retransmission control information for the specific information by using resources separately set between the user terminals.

5. The user terminal of claim 4,

the retransmission of the specific information is sent in a unicast manner.

6. A method of wireless communication, comprising:

a step of receiving specific information transmitted by at least one of broadcasting and multicasting; and

and controlling reporting of retransmission control information for the specific information using a resource commonly set among a plurality of user terminals.

Images