阅读说明：本技术 用户终端以及无线通信方法 (User terminal and wireless communication method ) 是由 武田一树 永田聪 王理惠 郭少珍 侯晓林 于 2018-07-30 设计创作，主要内容包括：在将来的无线通信系统中,即使在PUCCH反复发送被使用的情况下,为了适当地发送UCI,本公开的用户终端的一个方式具有：控制单元,在被设定上行链路控制信道(物理上行链路控制信道(Physical Uplink Control Channel(PUCCH)))反复发送以及半静态HARQ-ACK(混合自动重发请求确认(Hybrid Automatic Repeat request Acknowledgement))码本的情况下,基于下行链路共享信道(物理下行链路共享信道(Physical Downlink Shared Channel(PDSCH)))候选时机、与接收到的PDSCH对应的HARQ-ACK的发送定时、以及PUCCH反复因子的至少一个,决定用于每个时隙的PUCCH发送的码本；以及发送单元,应用PUCCH反复发送来发送基于所述码本的HARQ-ACK。(In a future wireless communication system, even when PUCCH is used by repeated transmission, one embodiment of a user terminal according to the present disclosure includes: a Control unit configured to determine a codebook to be used for PUCCH transmission for each slot based on at least one of a Downlink Shared Channel (Physical Downlink Shared Channel (PDSCH)) candidate timing, a transmission timing of HARQ-ACK corresponding to a received PDSCH, and a PUCCH repetition factor, when an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)) repetition transmission and a semi-static HARQ-ACK (Hybrid Automatic Repeat request Acknowledgement) codebook are set; and a transmission unit configured to apply PUCCH repeated transmission to transmit HARQ-ACK based on the codebook.)

1. A user terminal, comprising:

a Control unit configured to determine a codebook to be used for PUCCH transmission for each slot based on at least one of a downlink Shared Channel (Physical downlink Shared Channel (PDSCH)) candidate timing, HARQ-ACK transmission timing corresponding to a received PDSCH, and a PUCCH repetition factor when an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)) repetition transmission and a semi-static HARQ-ACK (Hybrid Automatic Repeat request Acknowledgement) codebook are set; and

and a transmission unit configured to repeatedly transmit the HARQ-ACK based on the codebook using PUCCH.

2. The user terminal of claim 1,

the control unit determines a codebook to be used for the PUCCH transmission for each slot such that a maximum required codebook size is maintained between PUCCH repetitions.

3. The user terminal of claim 2,

the control unit sets dummy bits in order to maintain the maximum required codebook size.

4. The user terminal of claim 1,

the control unit performs control so that a valid HARQ-ACK is reported only when the valid PUCCH repetition factor is set.

5. The user terminal of claim 1,

the control unit determines the bit order in the codebook according to any one of the PDSCH candidate timing, the component carrier index, or the timing, or a combination thereof.

6. A wireless communication method of a user terminal, comprising:

a step of determining a codebook to be used for PUCCH transmission for each slot based on at least one of a downlink Shared Channel (Physical downlink Shared Channel (PDSCH)) candidate timing, a transmission timing of HARQ-ACK corresponding to a received PDSCH, and a PUCCH repetition factor when an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)) repetition transmission and a semi-static HARQ-ACK (Hybrid Automatic Repeat request Acknowledgement) codebook are set; and

and a step of transmitting HARQ-ACK based on the codebook by repeatedly transmitting through PUCCH.

Technical Field

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

Background

In a conventional LTE system (e.g., rel.8-13), a User terminal (User Equipment (UE)) transmits Uplink Control Information (UCI)) using at least one of an UL (Uplink)) data Channel (e.g., a Physical Uplink Shared Channel (PUSCH)) and an UL Control Channel (e.g., a Physical Uplink Control Channel (PUCCH)).

The UCI may include, for example, retransmission control Information (Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK)) for a Downlink Shared Channel (Physical Downlink Shared Channel (PDSCH)), a Scheduling Request (SR), Channel State Information (CSI)), and the like (non-patent document 1). The HARQ-ACK may also be referred to as ACK/NACK (negative-acknowledgement), A/N, etc.

Documents of the prior art

Non-patent document

Non-patent document 1: 3GPP TS 36.213V13.8.0 "Evolved Universal Radio Access (E-UTRA); physical layer procedures (Release 13) ", 12 months in 2017

Disclosure of Invention

Problems to be solved by the invention

In the conventional LTE system, repeated HARQ-ACK transmission using PUCCH can be applied only to a user terminal to which one serving cell is set. Even when HARQ-ACK retransmission is set to be active (enabled), several constraints need to be satisfied for HARQ-ACK retransmission.

In future wireless communication systems (e.g., New Radio (NR)), use of repeated PUCCH transmission is also being studied. However, the restriction of the conventional LTE system has not been studied in detail with respect to repeated PUCCH transmission in a future wireless communication system (for example, NR). Further, no study has been made as to whether or not HARQ-ACK repeated transmission for individual PDSCH is assumed to overlap in 1 slot. If the behavior of the user terminal is not clarified for these contents, HARQ-ACK transmission cannot be appropriately performed, and there is a concern that the throughput, frequency utilization efficiency, and the like of communication may deteriorate.

The present invention has been made in view of the above, and an object thereof is to provide a user terminal and a radio communication method capable of appropriately transmitting UCI even when PUCCH is repeatedly transmitted in a future radio communication system.

Means for solving the problems

A user terminal according to an aspect of the present invention includes: a Control unit configured to determine a codebook to be used for PUCCH transmission for each slot based on at least one of a Downlink Shared Channel (Physical Downlink Shared Channel (PDSCH)) candidate timing, a transmission timing of HARQ-ACK corresponding to a received PDSCH, and a PUCCH repetition factor, when an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)) repetition transmission and a semi-static HARQ-ACK (Hybrid Automatic Repeat request Acknowledgement) codebook are set; and a transmission unit for transmitting the codebook-based HARQ-ACK by applying PUCCH repeated transmission

Effects of the invention

According to the present invention, in a future wireless communication system, UCI can be appropriately transmitted even when PUCCH is used for repeated transmission.

Drawings

Fig. 1 is a conceptual explanatory diagram of a restriction on HARQ-ACK retransmission in LTE.

Fig. 2 is a diagram illustrating an example of a case in which PUCCH repeated transmissions are not overlapped in one slot in embodiment 1.

Fig. 3 is a diagram illustrating an example of a case in which repeated PUCCH transmission is assumed to be non-overlapping in one slot in embodiment 1.

Fig. 4 is a diagram illustrating an example of PUCCH repetition transmission in embodiment 2.

Fig. 5 is a diagram showing an example of determination of a semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 6 is a diagram showing an example of setting of a semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 7 is a diagram showing an example of setting of a semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 8 is a diagram showing an example of setting of a semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 9 is a diagram showing an example of the bit order in the semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 10 is a diagram showing an example of the bit order in the semi-static HARQ-ACK codebook according to embodiment 3.

Fig. 11 shows an example of repeated PUCCH transmission in embodiment 4.

Fig. 12 is a diagram showing an example of a schematic configuration of a wireless communication system according to the present embodiment.

Fig. 13 is a diagram showing an example of a functional configuration of the radio base station according to the present embodiment.

Fig. 14 is a diagram showing an example of a functional configuration of a baseband signal processing section of a radio base station.

Fig. 15 is a diagram showing an example of a functional configuration of the user terminal according to the present embodiment.

Fig. 16 is a diagram showing an example of a functional configuration of a baseband signal processing section of a user terminal.

Fig. 17 is a diagram showing an example of hardware configurations of a radio base station and a user terminal according to an embodiment of the present invention.

Detailed Description

(HARQ-ACK retransmission in existing LTE System)

In the conventional LTE system, the repeated transmission of HARQ-ACK using PUCCH is applied only to a user terminal to which one serving cell is set. The one serving cell may be any one of a Frequency Division Duplex (FDD) cell and a Time Division Duplex (TDD) cell. In case that the one serving cell is a TDD cell, HARQ-ACK bundling is required for HARQ-ACK repeated transmission.

In the present disclosure, the repeated transmission of HARQ-ACK, HARQ-ACK repetition (HARQ-ACK retransmission), a/N repetition, UCI repetition, PUCCH repetition, repeated transmission, and the like may be replaced with each other.

HARQ-ACK retransmission can be set to the user terminal using a higher layer signaling, for example, "acknackpreemission" which is an RRC (Radio Resource Control) parameter. The RRC parameter includes a repetition factor (repetition factor). As the repetition factor, 2, 4, 6, and the like can be set.

In the present disclosure, the repetition factor and the repetition number (repetition number) may also be replaced with each other.

Even when HARQ-ACK repeated transmission is set to be effective, the following restrictions exist for HARQ-ACK repeated transmission.

The user terminal does not repeat with the sub-frame (N-N) in the sub-frame N_ANRep-3) PDSCH transmission to subframe (n-5) corresponding HARQ-ACK transmission. Here, N is_ANRepCorresponding to the repetition factor.

The user terminal replies with HARQ-ACK corresponding to PDSCH detected in sub-frame (N-4) only from sub-frame N to sub-frame (N + N)_ANRep-1) is transmitted.

The user terminal is in sub-frame N to sub-frame (N + N)_ANRepNo other signals or channels are transmitted in-1).

The user terminal does not repeat the transmission from the sub-frame (N-3) to the sub-frame (N + N)_ANRep-the detected PDSCH in 5) sends a corresponding HARQ-ACK acknowledgement.

Fig. 1 is a conceptual explanatory diagram of a restriction on HARQ-ACK retransmission in a conventional LTE system. In the example shown in FIG. 1, it is assumed that the sub-frame (n-7) to the sub-framePDSCH is not detected in the frame (n-5), and PDSCH for the user terminal is detected in the sub-frame (n-4) to the sub-frame (n-2). In the example shown in FIG. 1, N corresponds to the repetition factor_ANRep＝4。

In fig. 1, since the PDSCH is not detected in the sub-frames (n-7) to (n-5), the user terminal does not repeat HARQ-ACK transmission corresponding to the PDSCH transmission in the sub-frames (n-7) to (n-5) in the sub-frame n.

The user terminal repeatedly transmits only HARQ-ACKs corresponding to PDSCHs detected in the subframe (n-4) from the subframe n to the subframe (n + 3).

The user terminal cannot transmit other signals or channels from subframe n to subframe (n + 3). The user terminal cannot repeatedly transmit HARQ-ACK responses corresponding to PDSCH transmissions detected in the sub-frames (n-3) to (n-1).

(HARQ-ACK codebook)

In future wireless communication systems (e.g., NR), semi-static or dynamic (dynamic) decision of HARQ-ACK codebook (also referred to as HARQ-ACK size) by a user terminal is being studied. The base station may notify the user terminal of information indicating a method of determining the HARQ-ACK codebook, for example, information indicating whether the HARQ-ACK codebook is semi-static or dynamic, for each component carrier, each Cell Group (CG), each PUCCH Group, or each user terminal, through higher layer signaling.

The HARQ-ACK codebook may also be replaced by the HARQ-ACK codebook for PDSCH, the HARQ-ACK codebook size, the number of HARQ-ACK bits, etc.

In the present disclosure, the higher layer signaling may also be any one of RRC signaling, MAC (Medium Access Control) signaling, broadcast information, or a combination of these, for example.

MAC signaling may also use, for example, a MAC Control Element (MAC CE), a MAC PDU (Protocol Data Unit), or the like. The broadcast Information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Minimum System Information (Remaining Minimum System Information (RMSI)), Other System Information (OSI)), or the like.

The user terminal may determine (generate) HARQ-ACK information bits for each component carrier, each cell group, each PUCCH group, or each user terminal based on the determined HARQ-ACK codebook, and may transmit the generated HARQ-ACK using at least one of an uplink control channel (PUCCH) or an uplink shared channel (PUSCH).

When the user terminal is set to determine the HARQ-ACK codebook semi-statically or when the semi-static HARQ-ACK codebook is set, the determination of the HARQ-ACK codebook may be referred to as type 1HARQ-ACK codebook determination. When the user terminal is set to dynamically determine the HARQ-ACK codebook or when the user terminal is set to dynamically determine the HARQ-ACK codebook, the determination of the HARQ-ACK codebook may be referred to as type 2HARQ-ACK codebook determination.

The type 1HARQ-ACK codebook and the semi-static HARQ-ACK codebook may be replaced with each other. The type 2HARQ-ACK codebook and the dynamic HARQ-ACK codebook may be replaced with each other.

The user terminal may determine the number of HARQ-ACK bits or the like based on a configuration set by higher layer signaling in the type 1HARQ-ACK codebook determination. The configuration set may include, for example, DL (Downlink) transmission scheduled over a range associated with the feedback timing of HARQ-ACK, a maximum number or a minimum number of PDSCHs, and the like.

This range is also referred to as a HARQ-ACK bundling window (bundling window), HARQ-ACK feedback window, bundling window, feedback window, etc. The bundling window may also correspond to at least one range of space (space), time (time), and frequency (frequency).

The user terminal may determine the number of HARQ-ACK bits based on Downlink control information, for example, a bit string of a DL Assignment Index (DAI) field included in DL Assignment (Assignment) in the type 2HARQ-ACK codebook determination.

The DAI field may also indicate at least one of a total DAI and a counter DAI.

The total DAI is information on the total number of scheduled DL data (PDSCH), and may be equivalent to the total number of bits of HARQ-ACK fed back by the user terminal or the codebook size.

The counter DAI is information related to an accumulated value of scheduled DL data (PDSCH). For example, the counter DAI numbered in the order of the component carrier index may be included in Downlink Control Information (DCI) of one or more component carriers detected in a certain time unit, for example, in a slot or a subframe. In the case of collectively feeding back HARQ-ACKs for PDSCHs scheduled over a plurality of time units, for example, in the case where the bundling window is composed of a plurality of slots, the counter DAI may be applied over the plurality of time units.

(PDSCH-to-ACK timing)

In a future wireless communication system (for example, NR), a user terminal determines the transmission timing of HARQ-ACK corresponding to a received PDSCH based on DCI scheduling the PDSCH. This timing may also be referred to as PDSCH-to-ACK timing, K1, etc. The DCI may also be referred to as DLDCI, DL assignment, DCI format 1_0, DCI format 1_1, and the like.

For example, when DCI format 1_0 is detected, the user terminal transmits HARQ-ACK corresponding to the PDSCH in slot (n + k) (e.g., k is an integer of 1 to 8) based on a slot n including a final symbol of the PDSCH based on a PDSCH-to-HARQ-timing-indicator field (HARQ-to-HARQ-timing-indicator field) included in the DCI.

When DCI format 1_1 is detected, the user terminal transmits HARQ-ACK corresponding to the PDSCH in slot (n + k) (e.g., k is an integer of 1 to 8) based on a PDSCH-to-HARQ-timing-indicator field (PDSCH-to-HARQ-timing-indicator field) included in the DCI and including a final symbol of the PDSCH. Here, the correspondence relationship between k and the timing indication field may be set to the user terminal for each PUCCH, each PUCCH group, or each cell group by higher layer signaling.

For example, the correspondence relationship may be set by a parameter included in a PUCCH configuration information element (PUCCH configuration information element) in RRC signaling. This parameter may also be referred to as dl-DataToUL-ACK, Slot-timing-value-K1, etc. For example, K1 may be used to set a plurality of candidate values for PDSCH-to-ACK timing indication by higher layer signaling, and one of the plurality of candidate values may be indicated by DCI for scheduling of PDSCH.

K1 may be set for each PUCCH group or for each cell group. K1 may also be a time that is determined based on a parameter set (e.g., subcarrier spacing) of a channel, e.g., PUCCH or PUSCH, on which the HARQ-ACK is transmitted.

(HARQ-ACK repeat Transmission in NR)

In a future wireless communication system (for example, NR), PUCCH repetition transmission can be set by higher layer signaling for PUCCH formats 1, 3, and 4 having a transmission period of 4 symbols or more. The repetition factor may be set in common for all PUCCH formats 1, 3, and 4.

The user terminal may repeatedly transmit UCI transmitted through the PUCCH in the first slot of the slot in which the repeated transmission is performed, and also in the remaining slots in which the repeated transmission is performed. In each slot to which the repeated transmission is applied, the number of symbols for the PUCCH and the start symbol may be the same. The PUCCH repetition transmission may be performed in consecutive slots or may be performed in non-consecutive slots.

However, restrictions such as those of the conventional LTE system have not been studied in detail with respect to repeated PUCCH transmission in a future wireless communication system (for example, NR). Further, no study has been advanced as to whether to allow (or conceive) overlapping of repeated transmission of HARQ-ACK for another PDSCH in 1 slot. If the behavior of the user terminal is not clarified for these contents, HARQ-ACK transmission cannot be appropriately performed, and there is a concern that the throughput, frequency utilization efficiency, and the like of communication may deteriorate.

Therefore, in a future wireless communication system (e.g., NR), even in a case where PUCCH repeated transmission is used, the present inventors conceived a setting for appropriately transmitting UCI and operations of a user terminal and a base station.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The wireless communication methods of the respective embodiments may be applied individually or in combination.

In the following embodiments, PUCCH and PUCCH repetition transmission may be replaced with each other.

(Wireless communication method)

< embodiment 1>

In embodiment 1, a restriction on repeated PUCCH transmission will be described. Embodiment 1.1 corresponds to a case where there is no restriction or less restriction on repeated transmission of PUCCH. Embodiment 1.2 corresponds to a case where there are restrictions or a large number of restrictions on the repeated transmission of the PUCCH.

< embodiment mode 1.1>

In embodiment 1.1, PUCCH repetition may be used in any UCI type. The PUCCH repetition can also be used in any one of a case where UCI is periodically transmitted, a case where UCI is aperiodically transmitted, and a case where UCI is transmitted using a semi-persistent resource. The case where the UCI is periodically transmitted refers to, for example, Periodic CSI (P-CSI) reporting. The case where UCI is transmitted aperiodically refers to, for example, Aperiodic CSI (a-CSI) reporting. The case of being transmitted by the Semi-persistent resource refers to, for example, Semi-persistent CSI (SP-CSI) reporting.

The UCI type may also mean any one of HARQ-ACK, positive SR or negative SP, CSI including CSI part (part)1, CSI part 2, or the like, or a combination of these.

The CSI may also include at least one of a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a CSI-RS Resource Indicator (CRI), an SS/PBCH Block Resource Indicator (SSBRI), a Layer Indicator (LI)), a Rank Indicator (RI), a Reference Signal Received Power (Layer 1Reference Signal Power (L1-RSRP)) in Layer 1, a L1-RSRQ (Reference Signal Received Quality), a L1-SINR (Signal to Interference plus Noise Ratio), a L1-SNR (Signal to Noise Ratio), and the like.

CSI part 1 may also contain information with a relatively small number of bits, such as RI and wideband CQI. The CSI portion 2 may include information with a relatively large number of bits, such as information determined based on the CSI portion 1, for example, a partial band (subband) CQI and a PMI.

When PUCCH repetition transmission is set in a certain control unit, the user terminal may repeatedly transmit UCI (e.g., any one of HARQ-ACK, SR, or CSI, or a combination thereof) in the PUCCH for one or more (e.g., all) Component Carriers (CCs)) in the control unit.

In the present disclosure, the control unit may be any one of, for example, a Component Carrier (CC), a CC group, a cell group, a PUCCH group, a MAC entity, a Frequency Range (FR), a band, or a BWP (BandWidth Part), or a combination thereof. The above control unit may also be simply referred to as a group.

When the user terminal is set to repeat PUCCH transmission, it is also conceivable that a plurality of PUCCH repeated transmissions do not overlap in 1 slot. For example, when PUCCH retransmission is set, the user terminal may not expect DL Semi-persistent Scheduling (SPS), SR, P-CSI report, and SP-CSI report, which are set to have a shorter period than the duration (duration) of PUCCH retransmission. The duration of the PUCCH repetition transmission may be a slot of an amount corresponding to the repetition factor.

Fig. 2 is a diagram showing an example of a case where repeated PUCCH transmission is assumed to be non-overlapping in 1 slot in embodiment 1. In the example shown in fig. 2, the user terminal is repeatedly transmitted through the PUCCH with 2 slots set, that is, the repetition factor K is 2. In this case, the user terminal may also be conceived as a DL semi-persistent scheduling (SPS), SR, P-CSI report, and SP-CSI report which are not set to have a shorter periodicity than 2 slots. In the example shown in fig. 2, for example, it is assumed that at least one period of DL semi-persistent scheduling (SPS), SR, P-CSI report, and SP-CSI report set to a user terminal is 4 slots.

For example, when a user terminal transmits HARQ-ACK for DL semi-persistent scheduling (SPS) using PUCCH, since slots used for repeated PUCCH transmission are slot #4n and slot #4n +1(n is 0, 1, and …), multiple repeated PUCCH transmissions do not overlap in the same slot.

When PUCCH repetition transmission is set and at least one of DL semi-persistent scheduling (SPS), SR, P-CSI report, and SP-CSI report having a periodicity shorter than the duration of PUCCH repetition transmission is set, the user terminal may overwrite (override) the previous PUCCH repetition transmission with the latest PUCCH repetition transmission different from the PUCCH repetition transmission.

Fig. 3 is a diagram showing an example of a case where repeated PUCCH transmission is assumed to be non-overlapping in 1 slot in embodiment 1. In the example shown in fig. 3, the user terminal is repeatedly transmitted through the PUCCH with 8 slots set, that is, the repetition factor K is 8. It is contemplated that at least one period among DL semi-persistent scheduling (SPS), SR, P-CSI report, and SP-CSI report set to the user terminal is 4 slots.

In the example shown in fig. 3, the first PUCCH repeated transmission (PUCCH repeated transmission from slot #0 to slot # 7) from slot #0 partially overlaps the second PUCCH repeated transmission (PUCCH repeated transmission from slot #4 to slot # 11) from slot # 4. The user terminal may transmit the second PUCCH repetition transmission, which is the latest PUCCH repetition transmission, in slot #4 to slot # 7.

When the second PUCCH repetition transmission is started in the middle of the first PUCCH repetition transmission, the user terminal may interrupt the first PUCCH repetition transmission that is started earlier, and overwrite the latest second PUCCH repetition transmission.

PUCCH repetition transmission may be used for 1 carrier or for multiple carriers. PUCCH repetition transmission may also be used for either FDD and TDD carriers.

PUCCH repetition transmission may also be used for any data type with certain requirements, e.g. delay, reliability. The data type may be identified by, for example, a CRC (cyclic redundancy check) masked RNTI (Radio Network Temporary Identifier) of the data, or may be identified by a bearer of the data or a QCI (Quality of service Class Identifier).

< embodiment mode 1.2>

In embodiment 1.2, it is also conceivable that PUCCH repetition transmission is used for at least one of HARQ-ACK and SR, and not for other UCI types.

For example, a user terminal in which PUCCH repetition transmission is set may transmit HARQ-ACK for K PUCCH repetition transmissions. In this case, the user terminal may also not expect the HARQ-ACK of K PUCCH repetition transmissions to collide with other UCI types, e.g., SR or CSI.

When the user terminal collides with HARQ-ACK repeatedly transmitted by the PUCCH K times during transmission of other UCI types, the other UCI types may be discarded, or (pending) transmission may be retained.

The user terminal in which PUCCH repetition transmission is set may transmit at least one of HARQ-ACK and SR through K PUCCH repetition transmissions. In this case, the user terminal may be assumed to collide with the first iteration (first slot) of the HARQ-ACK for K PUCCH iteration transmissions during the SR period (SR occasion).

The ue may not expect that K PUCCH repetitions collide with other UCI types such as CSI. When the user terminal collides with HARQ-ACK repeated for K PUCCH times during transmission of other UCI types such as CSI, the user terminal may discard the other UCI types or may keep transmitting.

The PUCCH repetition transmission may be used by limiting at least one of the following conditions: the user terminal is not configured with non-carrier aggregation for carrier aggregation, carrier aggregation to X (for example, X ═ 2) component carriers, TDD (for example, with a UL/DL ratio in a specific range (0.4 or more) for FDD, and specific UL-DL configurations), non-code block group retransmission, HARQ-ACK bundling for PUCCH or both PUCCH and PUSCH, or HARQ-ACK bundling without at least PUCCH.

According to embodiment 1, it is possible to appropriately set the conditions or restrictions to be applied to repeated PUCCH transmission to the user terminal. The user terminal can process repeated PUCCH transmission based on appropriate assumptions.

< embodiment 2>

In embodiment 2, the user terminal to which PUCCH repetition is set may not desire PDSCH scheduling as follows: in a serving cell within 1 control unit, e.g., a cell group or a PUCCH group, HARQ-ACKs for different PDSCHs partially overlap in one or more slots. The user terminal may also envisage that the limitation of such scheduling of PDSCH is enforced by the scheduler of the base station.

After the user terminal determines PUCCH resources for repeated transmission in 1 control unit, for example, a cell group or a PUCCH group, pdcch (dci) for scheduling PDSCH overlapping a plurality of PUCCHs in one or a plurality of slots may be discarded (discard) or ignored (ignore) in the serving cell in the same control unit.

After the user terminal determines PUCCH resources for repetitive transmission in 1 control unit, it is also conceivable that scheduling of a PDSCH in which a plurality of PUCCHs are repeatedly transmitted and overlapped in one or a plurality of slots is not performed in the serving cell in the same control unit.

Fig. 4 is a diagram illustrating an example of PUCCH repetition transmission in embodiment 2. In the example shown in fig. 4, it is assumed that a control unit (for example, a cell group and a PUCCH group) including 2 DL component carriers (DL CC #1 and DL CC #2) is set, and HARQ-ACK retransmission is performed on the PUCCH of a specific UL component carrier (ULCC) based on the PDSCH in these DL component carriers. At least 2 component carriers of the DLCC #1, the DL CC #2, and the ULCC may also be included in the same component carrier.

The user terminal receives DCI #1 and DCI #3 in DL CC # 1. The user terminal receives DCI #2 and DCI #4 in DL CC # 2. The user terminal detects DCI #1 in a certain slot, DCI #2 in the next slot, and DCI #3 and DCI #4 in the next slot.

DCI #1 to DCI #4 may all be DCI scheduling PDSCH. Let K be 4, which is the value of repetition factor K for repeated PUCCH transmission.

DCI #1 indicates PUCCH repetition transmission from slot n to slot (n +3) of UL CC. For example, DCI #1 may indicate that the transmission timing of HARQ-ACK for the PDSCH scheduled through DCI #1 is from # n.

DCI #2 indicates PUCCH repetition transmission from slot (n +1) to slot (n +4) of the ULCC. DCI #3 and DCI #4 indicate PUCCH repetition transmission from slot (n +2) to slot (n +5) of the UL CC.

In the example shown in fig. 4, the user terminal starts PUCCH repetition transmission from slot n to slot (n +3) based on DCI # 1. Since PUCCH iterative transmission based on DCI #2 to DCI #4 overlaps with PUCCH iterative transmission based on DCI #1, the user terminal discards DCI #2 to DCI # 4.

According to embodiment 2, overlapping of repeated PUCCH transmissions can be suppressed, and complexity of processing in the user terminal can be suppressed.

< embodiment 3 >

In embodiment 3, a user terminal to which PUCCH repetition is set may be scheduled with a PDSCH as follows: in a serving cell within 1 control unit, e.g., a cell group or a PUCCH group, HARQ-ACKs for different PDSCHs partially overlap in one or more slots.

In embodiment 3, the user terminal assumes that a semi-static HARQ-ACK codebook is set for a specific cell, Cell Group (CG), PUCCH group, or the like. When the semi-static HARQ-ACK codebook is set, the user terminal transmits ACK/NACK for PDSCH candidates that can be scheduled, except for a specific exception condition. Therefore, the false detection of DCI of the user terminal does not affect the determination of the HARQ-ACK codebook. The specific exceptional condition is, for example, a case where a switch (switch) of a partial band gap (BWP) occurs.

When the semi-static HARQ-ACK codebook is set, the user terminal may generate HARQ-ACK bits for each PDSCH candidate and transmit the HARQ-ACK bits to the base station. The PDSCH candidate occasion is a PDSCH allocation candidate resource that the base station can schedule the user terminal using DCI. The base station may notify the user terminal of the transmission timing K1 of HARQ-ACK corresponding to each PDSCH candidate timing using DCI.

The user terminal determines (generates) HARQ-ACK information bits for HARQ-ACK transmission timing K1 that can be set by DCI, in addition to specific exceptional conditions. When the set PUCCH is repeatedly transmitted, the user terminal determines (generates) HARQ-ACK information bits to be transmitted in the PUCCH or PUSCH of K slots after the specific slot, based on the PDSCH reception.

The semi-static HARQ-ACK codebook may be configured such that the user terminal determines a codebook to be used for each PUCCH transmission in each slot based on at least one of (1) a PDSCH timing candidate recognized by RRC, (2) a K1 value list set by RRC, and (3) a PUCCH repetition factor notified by RRC.

Fig. 5 is a diagram showing an example of determination of a semi-static HARQ-ACK codebook according to embodiment 3. In the example shown in fig. 5, it is assumed that HARQ-ACK retransmission is performed on the PUCCH of a specific UL component carrier (UL CC) based on the PDSCH of the specific DL component carrier (DLCC). Let K be 4, which is the value of repetition factor K for repeated PUCCH transmission.

The user terminal receives DCI in a DL component carrier (DL CC). In fig. 5, the values of transmission timings K1 of all HARQ-ACKs that can be set by the DCI are indicated by 4 arrows. For example, when the value of HARQ-ACK transmission timing K1 indicated by the solid arrow is set in DCI, the transmission timing of HARQ-ACK for the PDSCH scheduled by the DCI starts from slot n.

Similarly, in fig. 5, when the value of the transmission timing K1 of HARQ-ACK indicated by the broken-line arrow is set for DCI, the transmission timing of HARQ-ACK for the PDSCH scheduled by the DCI starts from slot (n + 1). When the value of HARQ-ACK transmission timing K1 indicated by the arrow of the one-dot chain line is set in DCI, the transmission timing of HARQ-ACK for PDSCH scheduled by the DCI starts from slot (n + 2). When the value of HARQ-ACK transmission timing K1 indicated by the two-dot chain line arrow is set in the DCI, the transmission timing of HARQ-ACK for the PDSCH scheduled by the DCI starts from slot (n + 3).

Therefore, in fig. 5, the number of candidate a/ns that may be transmitted in slot N of the UL component carrier is 1 (solid arrow). The number of candidate a/ns that may be transmitted in slot (N +1) is 2 (solid arrow and dashed arrow). The number of candidate a/ns that may be transmitted in the slot (N +2) is 3 (solid line arrow, dotted line arrow, and dash-dot line arrow). The number of candidate a/ns that can be transmitted in the slot (N +3) is 4 (solid line arrow, broken line arrow, chain line arrow, and chain double-dashed line arrow). The number of candidate a/ns that may be transmitted in the slot (N +4) is 3 (dotted arrow, dashed arrow, and two-dot chain arrow). The number of candidate a/ns that may be transmitted in the slot (N +5) is 2 (the arrow of the chain line and the arrow of the chain double-dashed line). The number of candidate a/ns that may be transmitted in the time slot (N +6) is 1 (an arrow of a two-dot chain line).

As shown in fig. 5, regardless of which value of the transmission timing K1 of HARQ-ACK is set in DCI, the user terminal needs to generate 4 HARQ-ACK information bits in slot (n +3), for example.

Fig. 6 is a diagram showing an example of setting of a semi-static HARQ-ACK codebook according to embodiment 3. In the example shown in fig. 6, it is assumed that the codebook size and PUCCH format are different for each slot in PUCCH iterative transmission. Such setting is performed by RRC. Let K be 4, which is the value of repetition factor K for repeated PUCCH transmission.

In the example shown in fig. 6, it is assumed that a control unit (for example, a cell group or a PUCCH group) including 2 DL component carriers (DL CC #1 and DL CC #2) is set, and HARQ-ACK retransmission is performed on a PUCCH in a specific UL component carrier (ULCC) based on a PDSCH in these DL component carriers. At least 2 component carriers of DLCC #1, DL CC #2, and ULCC may be included in the same component carrier.

In DL CC #1 and DL CC #2, there are slots where PDSCH cannot be scheduled. For example, it is assumed that in a carrier that performs communication using TDD, a time slot in which PDSCH cannot be scheduled is set without setting DL resources.

The DCI scheduling PDSCH #1 sets HARQ-ACK transmission timing K1 for the PDSCH # 1.

When K1 is set to 4 by scheduling DCI of PDSCH #1, transmission of a/N (PDSCH #1w (and K1) in fig. 6) can be set in PUCCH from slot N to slot (N + 3).

When K1 is set to 5 by scheduling DCI of PDSCH #1, transmission of a/N (PDSCH #1w (and K1 is set to 5) in the PUCCH from slot (N +1) to slot (N +4) can be set.

When K1 is set to 6 by scheduling DCI of PDSCH #1, transmission of a/N (PDSCH #1w (and K1 to 6) in fig. 6) can be set in the PUCCH from slot (N +2) to slot (N + 5).

When K1 is set to 7 by scheduling DCI of PDSCH #1, transmission of a/N (PDSCH #1w (and K1 is 7) in the PUCCH from slot (N +3) to slot (N +6) not shown) can be set.

The DCI scheduling PDSCH #2 sets transmission timing K1 of HARQ-ACK for PDSCH # 2.

When K1 is set to 4 by scheduling DCI of PDSCH #2, transmission of a/N (PDSCH #2w (and K1 is set to 4) in the PUCCH from slot (N +1) to slot (N +4) can be set.

When K1 is set to 5 by scheduling DCI of PDSCH #2, transmission of a/N (PDSCH #2w (and K1 is set to 5) in the PUCCH from slot (N +2) to slot (N +5) can be set.

When K1 is set to 6 by scheduling DCI of PDSCH #2, transmission of a/N (PDSCH #2w (and K1 is 6) in the PUCCH from slot (N +3) to slot (N +6) not shown) can be set.

When K1 is set to 7 by scheduling DCI of PDSCH #2, transmission of a/N (PDSCH #2w (and K1 is set to 7) in the PUCCH of a slot from (N +4) to a slot (N +7) not shown in fig. 6) can be set.

DCI scheduling PDSCH #3 and PDSCH #4 sets transmission timing K1 of HARQ-ACK for PDSCH #3 or PDSCH # 4.

When the DCI for PDSCH #3 and PDSCH #4 is scheduled and K1 is set to 4, transmission of a/N (PDSCH #3w (and) K1 is 4, and PDSCH #4w (and) K1 is 4 in fig. 6) can be set in the PUCCH from slot (N +2) to slot (N + 5).

When the DCI for PDSCH #3 and PDSCH #4 is scheduled and K1 is set to 5, transmission of a/N (PDSCH #3w (and K1 is 5 and PDSCH #4w (and K1 is 5) in fig. 6) can be set in the PUCCH from slot (N +3) to slot (N +6) not shown.

When the DCI for PDSCH #3 and PDSCH #4 is scheduled and K1 is set to 6, transmission of a/N (PDSCH #3w (and) K1 is 6 and PDSCH #4w (and) K1 is 6 in fig. 6) can be set in the PUCCH from slot (N +4) to slot (N +7), not shown.

When K1 is set to 7 by scheduling DCI for PDSCH #3 and PDSCH #4, transmission of a/N (PDSCH #3w (and) K1 is 7 and PDSCH #4w (and) K1 is 7 in fig. 6) can be set in the PUCCH from slot (N +5) to slot (N +8), not shown.

In the example shown in fig. 6, regardless of which value of the transmission timing K1 of HARQ-ACK is set in DCI, the user terminal needs to generate 1 in slot n, 3 in slot (n +1), 7 in slot (n +2), 11 in slot (n +3), 13 in slot (n +4), and 13 HARQ-ACK information bits in slot (n + 5).

As shown in fig. 6, when it is assumed that the codebook size and the PUCCH format are different in each slot in the repeated PUCCH transmission, at least one of the codebook size and the PUCCH format may be different in each slot. Therefore, for example, there is a problem that soft-combining (soft-combining) of repeated PUCCHs is difficult to apply on the receiving side (base station in this case).

Therefore, the user terminal may determine at least one of the codebook size and PUCCH format between PUCCH repetitions based on the maximum required codebook size between PUCCH repetitions.

Regarding the semi-static HARQ-ACK codebook, the user terminal is notified of at least (1) a PDSCH timing candidate recognized by RRC, (2) a list of K1 values set by RRC, and (3) a PUCCH repetition factor notified by RRC. Therefore, the user terminal can determine the maximum required codebook size between PUCCH repetitions in advance.

The user terminal may determine at least one of a codebook size per slot and a PUCCH format so as to maintain the maximum required codebook size between PUCCH repetitions.

Fig. 7 is a diagram showing an example of the semi-static HARQ-ACK codebook setting according to embodiment 3. In the example shown in fig. 7, it is assumed that the user terminal is set to have K4 as the value of the repetition factor K for repeated PUCCH transmission.

In the example shown in fig. 7, 13 a/N transmissions are set in slot (N +4) or slot (N +5) to achieve the maximum required codebook size between PUCCH repetitions. In order to make the codebook size equal to the maximum required codebook size, the user terminal sets dummy bits (dummy bits) from slot n to slot (n + 3).

For example, since 1HARQ-ACK information bit needs to be generated in slot n, the user terminal sets 12 dummy bits. The dummy bits may be all 0's or 1's, or may be a scrambling sequence generated by a specific known encoding.

By setting dummy bits, at least one of the codebook size and the PUCCH format can be aligned between PUCCH repetitions.

In the example shown in fig. 6, the user terminal transmits ACK/NACK for PDSCH candidates that can be scheduled, in addition to specific exceptional conditions. Therefore, valid HARQ-ACKs are reported at all HARQ-ACK feedback occasions.

The user terminal may report only valid HARQ-ACKs based on the set transmission timing K1 of HARQ-ACK and the repetition factor K for repeated PUCCH transmission.

Fig. 8 is a diagram showing an example of setting of a semi-static HARQ-ACK codebook according to embodiment 3. In the example shown in fig. 8, it is assumed that K1 ═ {4, 5, 6, 7} is set as the transmission timing K1 of HARQ-ACK, and K1 ═ 4 is set as a value of valid K1 in the user terminal. Let K be 4, which is the value of repetition factor K for repeated PUCCH transmission.

As shown in fig. 8, the user terminal may report an effective HARQ-ACK only when K1 is set to 4 by scheduling DCI for PDSCH #1 to # 4. The user terminal may report NACK assuming that K1 ═ 5, 6, 7 is set by scheduling DCI for PDSCH #1 to # 4.

In this way, the HARQ-ACK codebook may include HARQ-ACKs valid for all PDSCHs or may include only HARQ-ACKs valid for PDSCHs associated with the PDCCH thereafter, except for specific exceptional conditions.

The HARQ-ACK codebook size may also contain HARQ-ACKs that are valid for X PDSCHs. Here, X ≦ Y, Y is the number of PDSCHs for all associations, and X is the number of PDSCHs determined depending on the maximum payload of the PUCCH resource shown. The user terminal may also discard (Y-X) HARQ-ACKs for the associated PDSCH.

Next, the bit sequence in the semi-static HARQ-ACK codebook when PUCCH repetition transmission is performed will be described.

The bit order in the semi-static HARQ-ACK codebook when PUCCH is repeatedly transmitted may be determined by any one of the following rules or a combination of the rules: (1) the PDSCH timing sequences are arranged in the order of the PDSCH timings from early to late in time, (2) in the order of the CC indexes from low to high, and (3) in the order of the K1 values from small to large.

Fig. 9 is a diagram showing an example of the bit order in the semi-static HARQ-ACK codebook according to embodiment 3. As shown in fig. 6, the user terminal sets HARQ-ACK information bits in each slot of the UL component carrier.

In the example shown in fig. 9, the bit sequence of the HARQ-ACK information bits in slot (n +4) is shown as pattern a and pattern B.

Pattern a of fig. 9 shows an example in which (1) a rule that the PDSCH timings are arranged in order from early to late in time is applied, and then (3) a rule that the K1 values are arranged in order from small to large is applied to determine the bit order in the HARQ-ACK codebook.

Pattern B of fig. 9 shows an example in which (3) the rule of arranging K1 in order from small to large is applied, and (1) the rule of arranging PDSCH timings in order from early to late is applied, and the order of bits in the HARQ-ACK codebook is determined.

Alternatively, the bit order in the semi-static HARQ-ACK codebook when PUCCH is repeatedly transmitted may be determined by any one of the following rules or a combination of the rules: (4) the PDSCH timing sequences are arranged in order from late to early in time, (5) in order of CC index from high to low, and (6) in order of K1 from high to low.

Fig. 10 is a diagram showing an example of the bit order in the semi-static HARQ-ACK codebook according to embodiment 3. As shown in fig. 6, the user terminal sets HARQ-ACK information bits in each slot of the UL component carrier.

In the example shown in fig. 10, pattern a and pattern B are shown as the bit sequence of HARQ-ACK information bits in slot (n + 4).

Pattern a of fig. 10 shows an example in which (4) a rule arranged in the order of PDSCH timings from late to early in time is applied, and then (6) a rule arranged in the order of K1 values from large to small is applied to determine the bit order in the HARQ-ACK codebook.

Pattern B of fig. 10 shows an example in which after (6) the rule of arranging K1 in descending order of value is applied, (4) the rule of arranging PDSCH timing in descending order of time is applied, and the order of bits in the HARQ-ACK codebook is determined.

Although fig. 9 and 10 show an example in which the bit order of the HARQ-ACK information bits is decided by applying any two combinations in the rules from (1) to (3), or (4) to (6), the method of deciding the bit order is not limited to this. The bit sequence may be determined by applying any of the rules (1) to (3) or (4) to (6). The bit sequence may be determined by applying any two combinations other than the combinations shown in fig. 9 and 10 to the rules (1) to (3) or (4) to (6). Note that, when PUCCH repetition transmission is not performed, the bit sequence of the HARQ-ACK information bits described above can be determined similarly by (1) to (6).

According to embodiment 3, even when PUCCH repeated transmissions overlap, the user terminal can select and transmit an appropriate UCI.

< embodiment 4 >

In embodiment 4, a user terminal in which PUCCH retransmission is set may be scheduled with a PDSCH as follows: in a serving cell within 1 control unit, e.g., a cell group or PUCCH group, HARQ-ACKs for different PDSCHs in one or more slots are repeatedly transmitted in non-overlapping symbols. The user terminal may also report UE capabilities (capabilities) to the base station informing whether such scheduling is possible using higher layer signaling.

It is also conceivable that the user terminal overlaps a plurality of PUCCH repetition transmission periods, and the resources used for respective PUCCH repetition transmissions do not overlap in time.

Fig. 11 shows an example of repeated PUCCH transmission in embodiment 4. The example shown in fig. 11 differs from the example shown in fig. 4 in that: the user terminal does not receive DCI #3 in DL CC #1, and detects DCI #3 instructing PUCCH repetition transmission from slot (n +1) to slot (n +4) of the UL CC in DL CC # 2.

In the example shown in fig. 11, the user terminal starts PUCCH repeated transmission from slot n to slot (n +3) based on DCI # 1. The user terminal starts PUCCH repetition transmission from slot (n +1) to slot (n +4) based on DCI #2 and DCI # 3. For example, in slot (n +1), the PUCCH based on DCI #1 and the PUCCH based on DCI #2 and DCI #3 are scheduled to different symbols.

Since the PUCCH resource for HARQ-ACK transmission of DCI #1 is different from the PUCCH resources for HARQ-ACK transmission of DCI #2 and DCI #3, the codebook size and PUCCH format used for repeated transmission of these PUCCHs may be determined differently. The user terminal may determine the PUCCH resource for HARQ-ACK transmission of DCI based on at least one of DCI and higher layer signaling (e.g., RRC signaling).

According to embodiment 4, even when the PUCCH repetition transmission periods overlap, the user terminal can transmit UCI using different PUCCH resources.

< embodiment 5 >

In embodiment 5, it is also conceivable that a UE in which PUCCH repetition is set has the following restrictions for PUCCH repetition.

The user terminal does not repeat HARQ-ACK transmission corresponding to PDSCH transmission in slot { x } in slot n. Here, { x } corresponds to a time slot or a time slot group earlier in time than the time slot (n-K1).

User terminal in time slot N to time slot (N + N)_ANRep-1) only transmitting HARQ-ACK acknowledgements corresponding to PDSCH detected in time slot (n-K1). Here, N is_ANRepCorresponding to the repetition factor.

User terminal in time slot N to time slot (N + N)_ANRepNo other signals or channels are transmitted in-1).

The user terminal does not repeat the transmission from time slot (N-K1) to time slot (N + N)_ANRepThe detected PDSCH in-K1-1) sends a corresponding HARQ-ACK acknowledgement.

The user terminal may restrict scheduling of pdcch (DCI) earlier than a certain DCI, such as repeated transmission of PUCCH based on the DCI being superimposed on repeated transmission of another PUCCH. In addition, the user terminal may restrict the setting of HARQ-ACK feedback for pdcch (DCI) earlier than a certain DCI, such as overlapping repeated transmission of PUCCH based on the certain DCI with repeated transmission of another PUCCH.

According to embodiment 5, overlapping of repeated PUCCH transmissions can be suppressed, and complexity of processing in the user terminal can be suppressed.

In addition, the generation of HARQ-ACK, the transmission of HARQ-ACK, the determination of HARQ-ACK, and the specification of HARQ-ACK in this disclosure may be replaced with each other. In addition, the HARQ-ACK, NACK, A/N, HARQ-ACK bits, etc. in this disclosure may also be substituted for each other. Furthermore, HARQ-ACK may also be replaced with any UCI, e.g., SR or CSI, or a combination of UCI.

The base station may perform UCI or HARQ-ACK reception processing (decoding, etc.) assuming the user terminal operation according to each embodiment, or may perform scheduling such as PDSCH or DCI for the user terminal.

(Wireless communication System)

The configuration of the radio communication system according to the present embodiment will be described below. In this radio communication system, the radio communication method according to the above-described embodiment is applied.

Fig. 12 is a diagram showing an example of a schematic configuration of a radio communication system according to the present embodiment. In the wireless communication system 1, Carrier Aggregation (CA) or Dual Connectivity (DC) can be applied in which a plurality of basic frequency blocks (component carriers) are integrated into one unit of 1 system bandwidth (for example, 20MHz) of the LTE system. The wireless communication system 1 may also be referred to as SUPER 3G, LTE-a (LTE-Advanced), IMT-Advanced, 4G, 5G, FRA (Future Radio Access), nr (new Radio), and the like.

The wireless communication system 1 includes: a base station 11 forming a macrocell C1, and base stations 12a to 12C arranged within a macrocell C1 and forming a small cell C2 narrower than the macrocell C1. The user terminal 20 is arranged in the macro cell C1 and each small cell C2. It is also possible to set a structure in which different parameter sets (Numerology) are applied between cells. The parameter set is a set of communication parameters that characterize the design of signals in a certain RAT or the design of a RAT.

User terminal 20 is capable of connecting to both base station 11 and base station 12. It is contemplated that the user terminal 20 simultaneously uses the macro cell C1 and the small cell C2 using different frequencies through Carrier Aggregation (CA) or Dual Connectivity (DC). Further, the user terminal 20 may apply Carrier Aggregation (CA) or Dual Connectivity (DC) with a plurality of cells (CCs) (e.g., 2 or less CCs). The user terminal can utilize the licensed band domain CC and the unlicensed band domain CC as a plurality of cells. Any one of the plurality of cells may include a configuration in which a TDD carrier for shortening TTI is applied.

The user terminal 20 and the base station 11 can communicate with each other using a Carrier having a narrow bandwidth (also referred to as an existing Carrier, Legacy Carrier, or the like) in a relatively low frequency band (e.g., 2 GHz). The user terminal 20 and the base station 12 may use a carrier having a wide bandwidth in a relatively high frequency band (e.g., 3.5GHz, 5GHz, 30 to 70GHz, etc.), or may use the same carrier as that used in the base station 11. The configuration of the frequency band used by each base station is not limited to this.

The base stations 11 and 12 (or 2 base stations 12) can be configured to perform wired connection (for example, an optical fiber based on a CPRI (Common Public Radio Interface), an X2 Interface, or the like) or wireless connection.

The base station 11 and each base station 12 are connected to the upper station apparatus 30, and are connected to the core network 40 via the upper station apparatus 30. The upper station apparatus 30 includes, for example, an access gateway apparatus, a Radio Network Controller (RNC), a Mobility Management Entity (MME), and the like, but is not limited thereto. Each base station 12 may be connected to the upper station apparatus 30 via the base station 11.

The base station 11 is a base station having a relatively wide coverage, and may be referred to as a macro base station, a sink node, an enb (enodeb), a transmission/reception point, or the like. The base station 12 is a base station having a local coverage area, and may be referred to as a small base station, a micro base station, a pico base station, a femto base station, an HeNB (home evolved node b) (home enodeb), an RRH (Remote Radio Head), a transmission/reception point, or the like. Hereinafter, base stations 11 and 12 will be collectively referred to as base station 10 without distinction.

Each user terminal 20 is a terminal supporting various communication schemes such as LTE and LTE-a, and may include not only a mobile communication terminal but also a fixed communication terminal.

In the wireless communication system 1, OFDMA (orthogonal frequency division multiple access) can be applied to the Downlink (DL) and SC-FDMA (single carrier-frequency division multiple access) can be applied to the Uplink (UL) as radio access schemes. OFDMA is a multicarrier transmission scheme in which a frequency band is divided into a plurality of narrow frequency bands (subcarriers) and data is mapped to each subcarrier to perform communication. SC-FDMA is a single-carrier transmission scheme in which a system bandwidth is divided into bands including one or consecutive resource blocks for each terminal, and a plurality of terminals use different bands to reduce interference between terminals. The uplink and downlink radio access schemes are not limited to these combinations, and OFDMA may be used in the UL.

In the radio communication system 1, as the DL Channel, a Downlink data Channel (Physical Downlink Shared Channel (PDSCH)), also referred to as a Downlink Shared Channel, or the like), a Broadcast Channel (Physical Broadcast Channel (PBCH)), a L1/L2 control Channel, or the like, which is Shared by each user terminal 20, is used. User data, higher layer control Information, SIB (System Information Block), and the like are transmitted through the PDSCH. MIB (Master Information Block) is transmitted through PBCH.

The L1/L2 Control channels include a Downlink Control Channel (Physical Downlink Control Channel (PDCCH)), an Enhanced Physical Downlink Control Channel (EPDCCH), a PCFICH (Physical Control Format Indicator Channel), a PHICH (Physical Hybrid-ARQ Indicator Channel), and the like, the Downlink Control Information (DCI)) including scheduling Information of the PDSCH and the PUSCH is transmitted through the PDCCH, the number of OFDM symbols for the PDCCH is transmitted through the PCFICH, the HARQ transmission acknowledgement Information (ACK/NACK) for the PUSCH is transmitted through the PHICH, the cch is frequency-division multiplexed with the PDSCH (Downlink shared data Channel), and is used for transmission of DCI and the like in the same manner as the PDCCH.

In the radio communication system 1, as the UL Channel, an Uplink data Channel (Physical Uplink Shared Channel (PUSCH)), also referred to as an Uplink Shared Channel, or the like), an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)), a Random Access Channel (Physical Random Access Channel (PRACH)), or the like, which is Shared by each user terminal 20, is used. User data, higher layer control information, etc. are transmitted through the PUSCH. Uplink Control Information (UCI)) including at least one of acknowledgement Information (ACK/NACK), radio quality Information (CQI), and the like is transmitted through a PUSCH or PUCCH, and a random access preamble for establishing connection with a cell is transmitted through the PRACH.

< base station >

Fig. 13 is a diagram showing an example of the overall configuration of the base station according to the present embodiment. The base station 10 includes a plurality of transmission/reception antennas 101, an amplifier unit 102, a transmission/reception unit 103, a baseband signal processing unit 104, a call processing unit 105, and a transmission line interface 106. The transmission/reception antenna 101, the amplifier unit 102, and the transmission/reception unit 103 may be configured to include one or more antennas. The base station 10 may be a downlink data transmitter or an uplink data receiver.

Downlink data transmitted from the base station 10 to the user terminal 20 is input from the upper station apparatus 30 to the baseband signal processing unit 104 via the transmission line interface 106.

In baseband signal processing section 104, for downlink Data, transmission processes such as PDCP (Packet Data Convergence Protocol) layer processing, segmentation/combination of user Data, RLC (Radio Link Control) layer transmission processing such as RLC retransmission Control, MAC (Medium Access Control) retransmission Control (for example, HARQ transmission processing), scheduling, transport format selection, channel coding, Inverse Fast Fourier Transform (IFFT) processing, and Precoding (Precoding) processing are performed, and the downlink Data is forwarded to transmitting/receiving section 103. Also, the downlink control signal is subjected to transmission processing such as channel coding and inverse fast fourier transform, and transferred to transmitting/receiving section 103.

Transmission/reception section 103 converts the baseband signal, which is precoded and output for each antenna from baseband signal processing section 104, to a radio frequency band and transmits the signal. The radio frequency signal frequency-converted by the transmission/reception section 103 is amplified by the amplifier section 102 and transmitted from the transmission/reception antenna 101. The transmitting/receiving unit 103 can be configured by a transmitter/receiver, a transmitting/receiving circuit, or a transmitting/receiving device described based on common knowledge in the technical field of the present invention. The transmission/reception unit 103 may be an integrated transmission/reception unit, or may be composed of a transmission unit and a reception unit.

For an uplink signal, a radio frequency signal received by transmission/reception antenna 101 is amplified by amplifier section 102. Transmission/reception section 103 receives the uplink signal amplified by amplifier section 102. Transmission/reception section 103 frequency-converts the received signal into a baseband signal, and outputs the baseband signal to baseband signal processing section 104.

The baseband signal processing section 104 performs Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing, error correction decoding, reception processing for MAC retransmission control, and reception processing for the RLC layer and the PDCP layer on the user data included in the input uplink signal, and transfers the user data to the upper station apparatus 30 via the transmission path interface 106. Call processing section 105 performs call processing such as setting and releasing of a communication channel, state management of base station 10, and management of radio resources.

The transmission line interface 106 transmits and receives signals to and from the upper station apparatus 30 via a specific interface. The transmission path Interface 106 may also transmit and receive signals (backhaul signaling) with other base stations 10 via an inter-base station Interface (e.g., an optical fiber based Common Public Radio Interface (CPRI), X2 Interface).

Further, the transmission/reception section 103 may further include an analog beamforming section for performing analog beamforming. The analog beamforming unit can be constituted by an analog beamforming circuit (e.g., phase shifter, phase shifting circuit) or an analog beamforming device (e.g., phase shifter) described based on common knowledge in the technical field of the present invention. The transmission/reception antenna 101 can be formed of, for example, an array antenna. The transmission/reception unit 103 is configured to be able to apply single BF or multiple BF.

The transmission/reception unit 103 may transmit a signal using a transmission beam or may receive a signal using a reception beam. The transmission/reception unit 103 may transmit and receive signals using a specific beam determined by the control unit 301.

Transmission/reception section 103 transmits a downlink signal (e.g., a downlink control signal (downlink control channel), a downlink data signal (downlink data channel, downlink shared channel), a downlink reference signal (DM-RS, CSI-RS, etc.), a discovery signal, a synchronization signal, a broadcast signal, etc.). The transmission/reception unit 103 receives an uplink signal (for example, an uplink control signal (uplink control channel), an uplink data signal (uplink data channel, uplink shared channel), an uplink reference signal, and the like).

Transmission/reception section 103 transmits 1 or more PDSCHs for which timing candidates are set over a plurality of slots.

Transmission/reception section 103 may transmit setting information for setting PUCCH repetition transmission and semi-static HARQ-ACK codebook to user terminal 20. The setting information of the PUCCH repetition transmission and the setting information of the semi-static HARQ-ACK codebook may be transmitted as separate information (e.g., separate RRC parameters) or may be transmitted as 1 piece of information.

The transmitting unit and the receiving unit of the present invention are configured by both or either one of the transmitting/receiving unit 103 and the transmission line interface 106.

Fig. 14 is a diagram showing an example of a functional configuration of a base station according to the present embodiment. In the figure, the functional blocks mainly representing the characteristic parts in the present embodiment are shown, and the base station 10 is assumed to have other functional blocks necessary for wireless communication as well. The baseband signal processing section 104 includes at least a control section 301, a transmission signal generation section 302, a mapping section 303, a reception signal processing section 304, and a measurement section 305.

Control section 301 performs overall control of base station 10. The control unit 301 can be configured by a controller, a control circuit, or a control device described based on common knowledge in the technical field of the present invention.

The control unit 301 controls, for example, generation of a signal by the transmission signal generation unit 302 and allocation of a signal by the mapping unit 303. The control unit 301 controls reception processing based on the signal of the reception signal processing unit 304, and measurement based on the signal of the measurement unit 305.

Control section 301 controls scheduling (e.g., resource allocation) of downlink signals and uplink signals. Specifically, control section 301 controls transmission signal generation section 302, mapping section 303, and transmission/reception section 103 so as to generate and transmit DCI (DL assignment (grant) including scheduling information of a downlink data channel and DCI (UL grant) including scheduling information of an uplink data channel.

Control section 301 may set a codebook size or a PUCCH format to be different for each slot in which PUCCH is repeatedly transmitted, and control scheduling of at least one of DCI and PDSCH with respect to user terminal 20 so that user terminal 20 performs PUCCH repeated transmission using the codebook or PUCCH format.

Transmission signal generating section 302 generates a downlink signal (downlink control channel, downlink data channel, downlink reference signal such as DM-RS, etc.) based on an instruction from control section 301, and outputs the downlink signal to mapping section 303. The transmission signal generating unit 302 can be configured by a signal generator, a signal generating circuit, or a signal generating device described based on common knowledge in the technical field of the present invention.

Mapping section 303 maps the downlink signal generated by transmission signal generating section 302 to a specific radio resource based on an instruction from control section 301, and outputs the result to transmitting/receiving section 103. The mapping unit 303 can be configured by a mapper, a mapping circuit, or a mapping device described based on common knowledge in the technical field of the present invention.

Reception signal processing section 304 performs reception processing (for example, demapping, demodulation, decoding, and the like) on the reception signal input from transmission/reception section 103. The received signal is, for example, an uplink signal (an uplink control channel, an uplink data channel, an uplink reference signal, etc.) transmitted from the user terminal 20. The received signal processing unit 304 can be configured by a signal processor, a signal processing circuit, or a signal processing device described based on common knowledge in the technical field of the present invention.

The received signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, the reception processing unit 304 shows at least one of the preamble, the control information, and the UL data to the control unit 301. Further, the received signal processing unit 304 outputs the received signal and the signal after the reception processing to the measurement unit 305.

The measurement unit 305 performs measurements related to the received signal. The measurement unit 305 can be configured by a measurement instrument, a measurement circuit, or a measurement device described based on common knowledge in the technical field of the present invention.

The measurement unit 305 may also measure, for example, the Received Power of the Received Signal (e.g., Reference Signal Received Power (RSRP)), the Received Quality (e.g., Reference Signal Received Quality (RSRQ)), the channel state, etc. the measurement result may also be output to the control unit 301.

< user terminal >

Fig. 15 is a diagram showing an example of the overall configuration of the user terminal according to the present embodiment. The user terminal 20 includes a plurality of transmission/reception antennas 201, an amplifier unit 202, a transmission/reception unit 203, a baseband signal processing unit 204, and an application unit 205. The transmission/reception antenna 201, the amplifier unit 202, and the transmission/reception unit 203 may be configured to include one or more antennas. The user terminal 20 may be a downlink data receiving apparatus or an uplink data transmitting apparatus.

The radio frequency signal received by the transmission/reception antenna 201 is amplified by the amplifier unit 202. Transmission/reception section 203 receives the downlink signal amplified by amplifier section 202. Transmission/reception section 203 frequency-converts the received signal into a baseband signal, and outputs the baseband signal to baseband signal processing section 204. The transmitting/receiving unit 203 can be configured by a transmitter/receiver, a transmitting/receiving circuit, or a transmitting/receiving device described based on common knowledge in the technical field of the present invention. The transmission/reception unit 203 may be an integrated transmission/reception unit, or may be composed of a transmission unit and a reception unit.

Baseband signal processing section 204 performs FFT processing, error correction decoding, reception processing of retransmission control, and the like on the input baseband signal. The downstream data is forwarded to the application unit 205. The application unit 205 performs processing related to a layer higher than the physical layer or the MAC layer, and the like. System information among the downlink data, or higher layer control information, is also forwarded to the application unit 205.

The uplink user data is input from the application unit 205 to the baseband signal processing unit 204. Baseband signal processing section 204 performs transmission processing for retransmission control (for example, transmission processing for HARQ), channel coding, precoding, Discrete Fourier Transform (DFT) processing, IFFT processing, and the like, and transfers the result to transmitting/receiving section 203. Transmission/reception section 203 converts the baseband signal output from baseband signal processing section 204 into a radio frequency band and transmits the converted signal. The radio frequency signal frequency-converted by the transmission/reception section 203 is amplified by the amplifier section 202 and transmitted from the transmission/reception antenna 201.

The transmission/reception section 203 may further include an analog beamforming section for performing analog beamforming. The analog beamforming unit can be constituted by an analog beamforming circuit (e.g., phase shifter, phase shifting circuit) or an analog beamforming device (e.g., phase shifter) described based on common knowledge in the technical field of the present invention. The transmission/reception antenna 201 can be formed of, for example, an array antenna. The transmission/reception unit 203 is configured to be able to apply single BF or multiple BF.

The transmission/reception unit 203 may transmit a signal using a transmission beam or may receive a signal using a reception beam. The transmission/reception unit 203 may transmit and receive signals using a specific beam determined by the control unit 401.

Transmission/reception section 203 receives a downlink signal (e.g., a downlink control signal (downlink control channel), a downlink data signal (downlink data channel, downlink shared channel), a downlink reference signal (DM-RS, CSI-RS, or the like), a discovery signal, a synchronization signal, a broadcast signal, or the like). Transmission/reception section 203 transmits an uplink signal (for example, an uplink control signal (uplink control channel), an uplink data signal (uplink data channel, uplink shared channel), an uplink reference signal, and the like).

Transmission/reception section 203 may transmit HARQ-ACK based on the codebook determined by control section 401 by applying PUCCH repetition transmission.

Fig. 16 is a diagram showing an example of a functional configuration of the user terminal according to the present embodiment. In the figure, the functional blocks mainly representing the characteristic parts in the present embodiment are shown, and the user terminal 20 is assumed to also have other functional blocks necessary for wireless communication. The baseband signal processing section 204 included in the user terminal 20 includes at least a control section 401, a transmission signal generation section 402, a mapping section 403, a reception signal processing section 404, and a measurement section 405.

Control section 401 performs overall control of user terminal 20. The control unit 401 can be configured by a controller, a control circuit, or a control device described based on common knowledge in the technical field of the present invention.

The control unit 401 controls, for example, generation of a signal by the transmission signal generation unit 402 and allocation of a signal by the mapping unit 403. The control unit 401 controls reception processing based on the signal of the reception signal processing unit 404 and measurement based on the signal of the measurement unit 405.

When uplink control channel (PUCCH) repeat transmission and a semi-static HARQ-ACK codebook are set, the control unit 401 may determine a codebook to be used for PUCCH transmission for each slot based on at least one of a downlink shared channel (PDSCH) candidate timing, a transmission timing of HARQ-ACK corresponding to a received PDSCH, and a PUCCH repetition factor.

Control section 401 may determine a codebook to be used for PUCCH transmission for each slot so that the maximum required codebook size is maintained during PUCCH repetition. The control unit 401 may also set dummy bits for the purpose of maintaining the maximum required codebook size.

Control section 401 may also perform control so that an effective HARQ-ACK is reported only when an effective PUCCH repetition factor is set. Control section 401 may determine the bit sequence in the codebook based on any one of or a combination of PDSCH candidate timing, component carrier index, and HARQ-ACK transmission timing.

Transmission signal generating section 402 generates an uplink signal (uplink control channel, uplink data channel, uplink reference signal, and the like) based on an instruction from control section 401, and outputs the uplink signal to mapping section 403. Transmission signal generating section 402 can be configured by a signal generator, a signal generating circuit, or a signal generating device described based on common knowledge in the technical field of the present invention.

Transmission signal generation section 402 generates an uplink data channel based on an instruction from control section 401. For example, when the UL grant is included in the downlink control channel notified from the base station 10, the transmission signal generation unit 402 is instructed from the control unit 401 to generate the uplink data channel.

Mapping section 403 maps the uplink signal generated by transmission signal generating section 402 to a radio resource based on an instruction from control section 401, and outputs the result to transmission/reception section 203. Mapping section 403 can be configured by a mapper, a mapping circuit, or a mapping device described based on common knowledge in the technical field of the present invention.

Received signal processing section 404 performs reception processing (for example, demapping, demodulation, decoding, and the like) on the received signal input from transmission/reception section 203. The reception signal is, for example, a downlink signal (downlink control channel, downlink data channel, downlink reference signal, etc.) transmitted from the base station 10. The received signal processing section 404 can be configured by a signal processor, a signal processing circuit, or a signal processing device described based on common knowledge in the technical field of the present invention. The received signal processing section 404 can constitute a receiving section according to the present invention.

Received signal processing section 404 blind-decodes the downlink control channel for scheduling transmission and reception of the downlink data channel based on the instruction from control section 401, and performs reception processing of the downlink data channel based on the DCI. The received signal processing unit 404 estimates a channel gain based on the DM-RS or the CRS, and demodulates the downlink data channel based on the estimated channel gain.

The received signal processing unit 404 outputs the information decoded by the reception processing to the control unit 401. Received signal processing section 404 outputs, for example, broadcast information, system information, RRC signaling, DCI, and the like to control section 401. The received signal processing unit 404 may also output the decoding result of the data to the control unit 401. The received signal processing unit 404 outputs the received signal and the signal after the reception processing to the measurement unit 405.

The measurement unit 405 performs measurements related to the received signal. The measurement unit 405 can be configured by a measurement instrument, a measurement circuit, or a measurement device described based on common knowledge in the technical field of the present invention.

The measurement unit 405 may also measure received power (e.g., RSRP), DL reception quality (e.g., RSRQ), or channel state, for example. The measurement result may also be output to the control unit 401.

(hardware construction)

The block diagrams used in the description of the above embodiments show 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 realized by 1 apparatus physically or logically combined, or may be realized by a plurality of apparatuses by directly or indirectly (for example, by wire, wireless, or the like) connecting 2 or more apparatuses physically or logically separated. The functional blocks may also be implemented by combining software in one or more of the above-described apparatuses.

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 (setting), reconfiguration (resetting), allocation (allocating, mapping), assignment (assigning), and the like, but 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. 17 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 following description, the expression "means" may be replaced with a circuit, a device, a unit, or the like. The hardware configurations of the base station 10 and the user terminal 20 may include 1 or more of each device shown in the drawing, or may not include some of the devices.

For example, the processor 1001 is only illustrated as 1, but a plurality of processors may be provided. The processing may be performed by 1 processor, or may be performed simultaneously, sequentially, or otherwise by more than 2 processors. The processor 1001 may also be implemented by 1 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, the baseband signal processing unit 104(204), the call processing unit 105, and the like can be implemented by the processor 1001.

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 401 of the user terminal 20 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 ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), or other 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)), a digital versatile Disc, a Blu-ray (registered trademark) disk (Blu-ray Disc)), 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 (key drive)), a magnetic stripe (stripe), a database, a server, and other suitable storage media. The storage 1003 may also be referred to as a secondary storage device.

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 transmission/reception antennas 101 and 201, the amplifier units 102 and 202, the transmission/reception units 103 and 203, the transmission line interface 106, and the like described above may be realized by the communication device 1004. The transmission/reception unit 103 may be implemented by physically or logically separating the transmission unit 103a and the reception unit 103 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).

The processor 1001 and the memory 1002 are connected to each other via 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 ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), 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 implemented with at least one of these hardware.

(modification example)

Terms described in relation to the present disclosure and terms required for understanding the present disclosure may also be replaced with terms having the same or similar meanings. For example, at least one of the channel and the symbol may also be a signal (signaling). The signal may also be a message. The reference signal may also be referred to as rs (reference signal) for short, and may also be referred to as Pilot (Pilot), Pilot signal, or the like according to the applied standard. Component Carriers (CCs) may also be referred to as cells, frequency carriers, Carrier frequencies, and the like.

The radio frame may be formed of 1 or more periods (frames) in the time domain. Each of the 1 or more periods (frames) constituting the radio frame may also be referred to as a subframe. Further, a subframe may also be composed of 1 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 be a communication parameter applied to at least one of transmission and reception of a certain signal or channel. For example, 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 performed by the transceiver in the frequency domain, and specific windowing performed by the transceiver in the Time domain may be indicated.

The time slot may be formed of 1 or more symbols in the time domain, for example, Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, or the like. 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 (mini slot) may also be formed of one or more symbols in the time domain. The mini-slots may also be referred to as subslots. 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 be referred to by other names corresponding to each.

For example, 1 subframe may be referred to as a Transmission Time Interval (TTI), a plurality of consecutive subframes may be referred to as a TTI, and 1 slot or 1 mini-slot may be referred to as a 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. 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. When a TTI is given, the time interval (e.g., number of symbols) to which transport blocks, code blocks, codewords, etc., are actually mapped may also be shorter than the TTI.

When 1 slot or 1 mini-slot is referred to as TTI, 1 or more TTI (i.e., 1 or more slot or 1 or more mini-slot) may be the minimum time unit for scheduling. The number of slots (mini-slots) constituting the minimum time unit of the schedule may also be controlled.

A TTI having a time length of 1ms may also be referred to as a normal TTI (TTI in LTE 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.

A long TTI (e.g., a normal TTI, a subframe, etc.) may be replaced with a TTI having a time length exceeding 1ms, and a short TTI (e.g., a shortened TTI, etc.) may be replaced with a TTI having a TTI length that is less than the TTI length of the long TTI and is 1ms or more.

A Resource Block (RB) is a Resource allocation unit in the time domain and the frequency domain, and may include 1 or more consecutive subcarriers (subcarriers) in the frequency domain.

The RB may include 1 or more symbols in the time domain, and may have a length of 1 slot, 1 mini-slot, 1 subframe, or 1 TTI. Each of the 1 TTI and 1 subframe may be formed of 1 or more resource blocks.

The 1 or more RBs may also be referred to as Physical Resource Blocks (PRBs), subcarrier groups (SCGs), Resource Element Groups (REGs), PRB pairs, RB pairs, and the like.

A Resource block may also be composed of 1 or more Resource Elements (REs). For example, 1RE may also be a radio resource region of 1 subcarrier and 1 symbol.

The above-described structures 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 be different from those explicitly disclosed in the present disclosure. Various channels, for example, a Physical Uplink Control Channel (PUCCH), a Physical Downlink Control Channel (PDCCH), and information elements can be identified by any appropriate names, and thus, 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 from at least one of the upper layer to the lower layer and from the lower layer to the upper 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 input/output information, signals, and the like 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 may be performed 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), MAC (Medium Access Control) signaling, other signals, or a combination thereof.

Physical Layer signaling may also be referred to as L1/L2 (Layer 1/Layer 2)) control information (L1/L2 control signals), L1 control information (L1 control signals), and the like. The RRC signaling may also be referred to as an RRC message, and may also be, for example, an RRC connection setup (RRCConnectionSetup) message, an RRC connection reconfiguration (RRCConnectionReconfiguration) message, or the like. The MAC signaling may be notified using a MAC Control Element (MAC CE), for example.

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 notifying the specific information or by notifying other information).

The determination may be performed by a value (0 or 1) represented by 1 bit, a true or false value (boolean value) represented by true (true) or false (false), or a comparison of values (for example, comparison with a specific 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, etc. may also be transmitted or received over 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.

In the present disclosure, terms such as "precoding", "precoder", "weight", "Quasi-Co-location (qcl)", "TCI state (Transmission Configuration indicator state)", "spatial relationship", "spatial filter", "Transmission power", "phase rotation", "antenna port group", "layer number", "rank", "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", "NodeB", "enodeb (enb)", "gnnodeb (gnb)", "access point", "transmission point", "reception point", "transmission/reception point", "cell", "sector", "cell group", "carrier", "component carrier", "bandwidth part (bwp)", and the like 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.

A base station can accommodate 1 or more (e.g., 3) cells (also referred to as sectors). 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-sized 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)", and "terminal" 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 communications 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 communication apparatus, and the like. At least one of the base station and the mobile station may be a device mounted on a mobile body, a mobile body main body, or the like. The mobile body may be a vehicle (e.g., a vehicle, 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 while performing communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

The base station in the present disclosure may also be replaced with a user terminal. 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 D2D (Device-to-Device), V2X (Vehicle-to-event), and the like). 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 replaced with expressions (for example, "side") corresponding to inter-terminal communication. For example, the uplink channel, the downlink channel, and the like may be replaced with the side channel.

Likewise, the user terminal in the present disclosure may also be replaced with a base station. 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 1 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, 1 or more network nodes other than the base station (for example, MME (Mobility Management Entity), S-GW (Serving-Gateway), etc. may be considered, but are 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 as execution proceeds. 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 LTE (Long Term Evolution), LTE-a (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (fourth generation Mobile communication System), 5G (fifth generation Mobile communication System), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New Radio Access), FX (New Radio Access), GSM (registered trademark) (Global System for Mobile communication), and CDMA (Radio Broadband) System (CDMA 2000) IEEE 802.11(Wi-Fi (registered trademark)), IEEE 802.16(WiMAX (registered trademark)), IEEE802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), a system using another appropriate wireless communication method, and a next generation system expanded based on these. Further, a plurality of systems may be combined (for example, LTE, or a combination of LTE-a and 5G).

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 more than 2 elements. Thus, reference to first and second elements does not imply that only 2 elements may be used or that the first element must somehow override the second element.

The term "determining" as used in this disclosure encompasses a wide variety of actions 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 (retrieving), inquiry (querying)) (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 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 (determination)" may be regarded as a case where the "judgment (determination)" is performed for some actions.

The "determination (determination)" may be replaced with "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), or 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, "connect" may also be replaced with "access".

In the present disclosure, where two elements are connected, it can be considered to be "connected" or "joined" to each other using more than one wire, cable, printed electrical connection, etc., and using electromagnetic energy having a wavelength in the radio frequency domain, the microwave region, the optical (both visible and invisible) region, etc., as several 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". 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 are intended to have inclusive meanings as in the term" comprising ". Further, the term "or" used in the present disclosure does not mean exclusive or.

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