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 松村祐辉 武田一树 永田聪 于 2019-02-14 设计创作，主要内容包括：本公开的一个方式的用户终端,其特征在于,具有：接收单元,接收来自第一发送接收点(Transmission/Reception Point(TRP))的第一PDSCH(物理下行链路共享信道(Physical Downlink Shared Channel))和来自第二TRP的第二PDSCH,所述第二PDSCH与所述第一PDSCH在时间以及频率资源的至少一方上重叠；以及控制单元,进行以下的控制：将对于所述第一PDSCH的第一HARQ-ACK(混合自动重发请求确认(Hybrid Automatic Repeat reQuestACKnowledgement))发送给所述第一TRP,并且将对于所述第二PDSCH的第二HARQ-ACK发送给所述第二TRP。根据本公开的一个方式,即使在利用多TRP的情况下也能够恰当地实施HARQ-ACK控制。(A user terminal according to an aspect of the present disclosure includes: a Reception unit configured to receive a first PDSCH (Physical Downlink Shared Channel) from a first Transmission/Reception Point (TRP) and a second PDSCH from a second TRP, the second PDSCH overlapping the first PDSCH in at least one of time and frequency resources; and a control unit that performs control of: transmitting a first HARQ-ACK (Hybrid Automatic Repeat request acknowledgement) for the first PDSCH to the first TRP, and transmitting a second HARQ-ACK for the second PDSCH to the second TRP. According to one embodiment of the present disclosure, HARQ-ACK control can be appropriately implemented even in a case where multiple TRPs are utilized.)

1. A user terminal, comprising:

a Reception unit configured to receive a first PDSCH (Physical Downlink Shared Channel) from a first Transmission/Reception Point (TRP) and a second PDSCH from a second TRP, the second PDSCH overlapping the first PDSCH in at least one of time and frequency resources; and

a control unit that performs the following control: transmitting a first HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement) for the first PDSCH to the first TRP, and transmitting a second HARQ-ACK for the second PDSCH to the second TRP.

2. The user terminal of claim 1,

the control unit decides resources for transmitting the first HARQ-ACK based on a group of resource sets for the first TRP and decides resources for transmitting the second HARQ-ACK based on a group of resource sets for the second TRP.

3. The user terminal of claim 1,

the control unit decides resources for transmitting the first HARQ-ACK and resources for transmitting the second HARQ-ACK based on a group of common resource sets.

4. The user terminal according to any of claims 1 to 3,

the Control unit performs Control such that, when spatial relationship information of a PUCCH (Physical Uplink Control Channel) of a first ID and spatial relationship information of a PUCCH of a second ID having a value greater than the first ID are activated: and if the ID of the second TRP is larger than the ID of the first TRP, transmitting the first HARQ-ACK based on the spatial relationship information of the PUCCH with the first ID, and if the ID of the second TRP is less than or equal to the ID of the first TRP, transmitting the first HARQ-ACK based on the spatial relationship information of the PUCCH with the second ID.

5. The user terminal according to any of claims 1 to 3,

the control unit envisages that the spatial relationship information for the first TRP and the spatial relationship information for the second TRP are activated separately, respectively.

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

a step of receiving a first PDSCH (Physical Downlink Shared Channel) from a first Transmission/Reception Point (TRP) and a second PDSCH from a second TRP, wherein the second PDSCH overlaps with the first PDSCH on at least one of time and frequency resources; and

the following control steps are carried out: transmitting a first HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement) for the first PDSCH to the first TRP, and transmitting a second HARQ-ACK for the second PDSCH to the second TRP.

Technical Field

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

Background

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

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

Documents of the prior art

Non-patent document

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

Disclosure of Invention

Problems to be solved by the invention

In future wireless communication systems (for example, NR), DL Transmission of one or more Transmission/Reception points (TRPs) to a User terminal (User Equipment (UE)) is being studied.

However, the NR specifications so far do not take into account multiple TRPs, and thus HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement) feedback in the case of using multiple TRPs cannot be appropriately controlled. Therefore, in the case of complying with the current NR specification, spatial diversity gain, high rank transmission, and the like in the case of using multiple TRPs cannot be appropriately realized, and an increase in communication throughput may be suppressed.

Accordingly, an object of the present disclosure is to provide a user terminal and a wireless communication method capable of appropriately performing HARQ-ACK control even when multiple TRPs are used.

Means for solving the problems

A user terminal according to an aspect of the present disclosure includes: a Reception unit configured to receive a first PDSCH (Physical Downlink Shared Channel) from a first Transmission/Reception Point (TRP) and a second PDSCH from a second TRP, the second PDSCH overlapping the first PDSCH in at least one of time and frequency resources; and a control unit that performs control of: transmitting a first HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement) for the first PDSCH to the first TRP, and transmitting a second HARQ-ACK for the second PDSCH to the second TRP.

Effects of the invention

According to one embodiment of the present invention, HARQ-ACK control can be appropriately performed even when multiple TRPs are used.

Drawings

Fig. 1A to 1D are diagrams showing an example of a multi-TRP scenario.

Fig. 2 is a diagram illustrating an example of a process of separating (separate) HARQ-ACK.

Fig. 3A and 3B are diagrams showing an example of separating the transmission timing of HARQ-ACK.

Fig. 4 is a diagram illustrating an example of setting a plurality of groups of PUCCH resource sets.

Fig. 5 is a diagram showing an example of a set in which a PUCCH resource set common to TRPs is set.

Fig. 6 is a diagram showing an example of setting a plurality of groups of PUCCH resource sets.

Fig. 7 shows an example of setting a plurality of groups of PUCCH resource sets.

Fig. 8 is a diagram showing an example of setting a plurality of groups of PUCCH resource sets.

Fig. 9 is a diagram showing an example of a set in which a PUCCH resource set common to TRPs is set.

Fig. 10 is a diagram illustrating an example of a flow of the joint HARQ-ACK.

Fig. 11 is a diagram illustrating an example of PUCCH resources for joint HARQ-ACK for a single PDCCH.

Fig. 12 is a diagram showing an example of PUCCH resources for joint HARQ-ACK for multiple PDCCHs.

Fig. 13 is a diagram illustrating an example of PUCCH resources for joint HARQ-ACK for multiple PDCCHs.

Fig. 14A and 14B are diagrams showing an example of a semi-static HARQ codebook.

Fig. 15A to 15D are diagrams illustrating an example of determination of a type of HARQ-ACK transmission based on PUCCH resources.

Fig. 16 is a diagram showing an example of a schematic configuration of a radio communication system according to an embodiment.

Fig. 17 is a diagram showing an example of the configuration of a base station according to an embodiment.

Fig. 18 is a diagram showing an example of the configuration of a user terminal according to an embodiment.

Fig. 19 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment.

Detailed Description

(multiple TRP)

In NR, one or more Transmission/Reception Point (TRP)) (multiple TRPs) are being studied for DL Transmission (e.g., PDSCH Transmission) to a UE using one or more panels (multiple panels).

Fig. 1A to 1D are diagrams showing an example of a multi-TRP scenario. It is envisaged in these examples that 4 different beams can be transmitted for each TRP, but this is not limiting.

Fig. 1A shows an example of a case (which may also be referred to as a single mode) where only one TRP (TRP1 in this example) among a plurality of TRPs transmits to a UE. In this case, TRP1 transmits both a control signal (PDCCH) and a data signal (PDSCH) to the UE.

Fig. 1B shows an example of a case where only one TRP (TRP1 in this example) among multiple TRPs transmits a control signal to a UE and the multiple TRPs transmits a data signal (may also be referred to as a single master mode). The UE receives PDSCHs transmitted from the multiple TRPs based on one Downlink Control Information (DCI).

Fig. 1C shows an example of a case where a plurality of TRPs transmit a part of a control signal to a UE and the plurality of TRPs transmit a data signal (may be referred to as a master-slave mode). Part 1 of the control signal (DCI) may be transmitted in TRP1 and part 2 of the control signal (DCI) may be transmitted in TRP 2. The portion 2 of the control signal may also depend on the portion 1. The UE receives the PDSCHs transmitted from the multiple TRPs based on the portions of the DCI.

Fig. 1D shows an example of a case where a plurality of TRPs transmit individual control signals to a UE and the plurality of TRPs transmit data signals (may also be referred to as a multi-master mode). The first control signal (DCI) may be transmitted to the TRP1 and the second control signal (DCI) may be transmitted to the TRP 2. The UE receives the PDSCHs transmitted from the multiple TRPs based on the DCIs.

As in fig. 1B, in the case where multiple PDSCHs from multiple TRPs are scheduled using one DCI, the DCI may also be referred to as a single DCI (single PDCCH). In addition, as shown in fig. 1D, when a plurality of PDSCHs from a plurality of TRPs are scheduled using a plurality of DCIs, the plurality of DCIs may be referred to as a multi-DCI (multi-PDCCH).

According to such a multi-TRP scenario, more flexible transmission control using a channel of good quality can be achieved.

Different codewords (Code Word (CW)) and different layers may be transmitted from each TRP of the multiple TRPs, respectively. As one mode of multi-TRP Transmission, Non-Coherent Joint Transmission (NCJT) is being studied.

In NCJT, for example, TRP1 modulation maps a first codeword and performs layer mapping such that a first number of layers (e.g., two layers) transmit a first PDSCH with a first precoding. Further, TRP2 modulation maps the second codeword and performs layer mapping to transmit the second PDSCH with the second precoding of the second number of layers (e.g., two layers). It is conceivable that these first PDSCH and second PDSCH do not satisfy Quasi-Co-Location (QCL) relationship (not Quasi-Co-located).

Further, it may be defined that a plurality of PDSCHs performing NCJT partially or completely overlap with respect to at least one of the time domain and the frequency domain.

However, the NR specifications so far do not take into account multiple TRPs, and thus HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement) feedback in the case of using multiple TRPs cannot be appropriately controlled. Therefore, in the case of complying with the current NR specification, spatial diversity gain, high rank transmission, and the like in the case of using multiple TRPs cannot be appropriately realized, and an increase in communication throughput may be suppressed.

Accordingly, the present inventors have conceived HARQ-ACK control capable of coping with the case of using multiple TRPs.

The present disclosure provides a method for determining an Uplink Control Channel (PUCCH))/Uplink Shared Channel (PUSCH) resource for transmitting HARQ-ACK for multiple PDSCHs scheduled by a PDCCH (e.g., multiple PDSCHs performing NCJT) for at least one of a single PDCCH and a multiple PDCCH. The PUCCH/PUSCH may denote at least one of PUCCH and PUSCH (the same applies hereinafter).

In an embodiment, it is proposed that each TRP sends HARQ-ACK in different PUCCH/PUSCH resources. This transmission scheme of HARQ-ACK feedback may also be referred to as separate HARQ-ACK feedback (transmission), individual HARQ-ACK feedback, etc.

If the split HARQ-ACK is used, it is possible to perform independent HARQ-ACK transmission for each TRP. Even in the case where the backhaul delay between the TRPs is large (for example, the TRPs are connected through a non-ideal backhaul), the delay of the HARQ does not become large.

In an embodiment, it is proposed to transmit HARQ-ACKs for each TRP in the same PUCCH/PUSCH resource. This transmission scheme of HARQ-ACK feedback may also be referred to as joint HARQ-ACK feedback (transmission), common HARQ-ACK feedback, etc.

If the joint HARQ-ACK is used, only one PUCCH/PUSCH transmission is sufficient, and thus resource overhead can be reduced. In addition, when the backhaul delay between the TRPs is small (for example, the TRPs are connected to each other through an ideal backhaul), the HARQ-ACK transmitted to one TRP can reach the other TRP with low delay.

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

In the present disclosure, a panel, an Uplink (UL) transmission entity, a TRP, a Demodulation Reference Signal (DMRS) port, a DMRS port group, a Code Division Multiplexing (CDM) group, a PDSCH, a codeword, a base station, and the like may be substituted for each other. In addition, a panel ID (Identifier) and a panel may be replaced with each other. The TRP ID and TRP may be substituted for each other. Further, the ID and the index may be replaced with each other.

Note that HARQ-ACK of the following embodiments may be replaced with Uplink Control Information (UCI). That is, the HARQ-ACK may be replaced with one of or a combination of the HARQ-ACK, Channel State Information (CSI), Scheduling Request (SR), and the like.

In addition, in the present disclosure, NCJT using multiple TRPs, multiple PDSCH using NCJT, multiple PDSCH from multiple TRPs, and the like may be substituted for each other.

(Wireless communication method)

< first embodiment >

The first embodiment relates to a split HARQ-ACK transmission. Each HARQ-ACK corresponding to the disjoint HARQ-ACK corresponds to a different pdsch (cw) and may be transmitted using at least one of the PUCCH and the PUSCH. The UE transmits the separated HARQ-ACKs to different TRPs, respectively.

The multiple PDSCHs (multiple PDSCHs) corresponding to the split HARQ-ACK may be transmitted simultaneously from each TRP or may be transmitted at different timings. The channel on which the PDSCHs are scheduled may be a single PDCCH or a multiple PDCCH.

Fig. 2 is a diagram showing an example of a flow of separating HARQ-ACK. In this example, the UE receives DCI1 and DCI2 constituting multiple PDCCHs from TRP1 and TRP2, respectively. Further, the UE receives PDSCH1(CW1) transmitted from TRP1 based on DCI1 and receives PDSCH2(CW2) transmitted from TRP2 based on DCI 2.

The UE transmits HARQ-ACK1(HARQ 1. hereinafter, HARQ-ACK may be abbreviated as HARQ) for PDSCH1 to TRP1, and transmits HARQ-ACK2(HARQ2) for PDSCH2 to TRP 2.

In this example, the TRP for transmitting DCI, the TRP for transmitting PDSCH scheduled by the DCI, and the TRP for receiving HARQ-ACK for the PDSCH are the same, but at least one of them may be different TRPs. The same applies to the following examples.

Fig. 3A and 3B are diagrams showing an example of separating the transmission timing of HARQ-ACK. The split HARQ-ACK may be transmitted in different slots (i.e., each slot using one PUCCH/PUSCH) (fig. 3A) or in one slot (i.e., each slot using multiple PUCCH/PUSCH) (fig. 3B), respectively.

In fig. 3A, HARQ1 and HARQ2 constituting the split HARQ-ACK are transmitted by the UE in different slots # m and # m +1, respectively. The same HARQ1 and HARQ2 are transmitted by the UE in the same slot # m. In addition, where separate HARQ-ACKs are sent in different slots, the slots may not be contiguous.

[ one PUCCH/PUSCH per slot ]

With respect to transmitting the split HARQ-ACK with one PUCCH/PUSCH per slot, the UE may be notified (set, indicated) with higher layer signaling, physical layer signaling (e.g., DCI scheduling at least one of multiple PDSCHs), or a combination thereof.

In addition, in the present disclosure, the higher layer signaling may be, for example, one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, and the like, or a combination thereof.

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

The physical layer signaling may also be DCI, for example.

In the case where the split HARQ-ACK is transmitted using one PUCCH/PUSCH per slot, the UE may transmit each HARQ-ACK using PUCCH/PUSCH resources compliant with Rel-15 NR.

In Rel-15 NR, a UE first decides one PUCCH resource set from 4 PUCCH resource sets (PUCCH resource sets 1 to 4) according to the size of UCI to be transmitted. When the UCI includes HARQ-ACK, the UE determines a PUCCH resource for transmitting the UCI based on a PUCCH resource indicator field included in DCI format 1_0 or 1_1 (and at least one of a CCE (Control Channel Element) index, a CCE number, and the like of CORESET that received the DCI) that specifies transmission timing of the HARQ-ACK.

In addition, in the case where there are a plurality of DCI formats 1_0 or 1_1 that specify transmission timings of HARQ-ACKs of the same slot, the UE may determine a PUCCH resource based on the PUCCH resource indicator field of the last (last) DCI format 1_0 or 1_1 of these DCIs. Here, "last DCI format 1_0 or 1_ 1" may refer to the last DCI format 1_0 or 1_1 to which an index is given in the same PDCCH monitoring opportunity (occasion) in the ascending order of the serving cell index and then given in the ascending order of the PDCCH monitoring opportunity index, or may refer to the last DCI format 1_0 or 1_1 received last in time.

The network may restrict such that the UE transmits a split HARQ-ACK with one PUCCH/PUSCH per slot. For example, with regard to HARQ-ACK transmission for multiple CWs (pdschs), the UE may not expect that multiple CWs, which are multi-TRP or multi-panel CWs for NCJT, are set at the same slot index.

The UE may decide to transmit (or discard) any of the following HARQ-ACKs when it is set to transmit a split HARQ-ACK using one PUCCH/PUSCH per slot and is set to transmit more than one HARQ-ACK for a plurality of CWs (pdschs) within one slot:

(1) HARQ-ACK that conforms to a TRP ID of a specific value (e.g., minimum, maximum),

(2) a HARQ-ACK that conforms to the same TRP ID as a single port transmission,

(3) the QCL hypothesis (or the QCL hypothesis for the corresponding PDSCH) is the same HARQ-ACK as the specific QCL hypothesis for the PDCCH.

Here, the specific QCL assumption for the PDCCH in (3) may be a default QCL assumption for the PDCCH, and may be, for example, a QCL assumption for a search space (or a search space set) of the latest slot of the smallest CORESET-ID.

[ multiple PUCCH/PUSCH per slot ]

Regarding transmitting the split HARQ-ACK using a plurality of PUCCH/PUSCH per slot, the UE may be notified (set, indicated) using higher layer signaling, physical layer signaling (e.g., DCI scheduling at least one of multiple PDSCHs), or a combination thereof.

The UE may be set with a PUCCH resource set for each TRP, for example, using higher layer signaling. According to this configuration, resources can be flexibly utilized.

More than one PUCCH resource set for one TRP may also be referred to as a group of PUCCH resource sets for the TRP. The group can be set to the UE using, for example, a TRP ID (or group ID) and a PUCCH resource set ID.

Fig. 4 is a diagram showing an example of setting a plurality of groups of PUCCH resource sets. In this example, the UE sets a PUCCH resource set group including PUCCH resource sets 1, 2, and … for each TRP. The maximum number of PUCCH resource sets may be 4 as in the conventional case, or may be a value different from 4.

In addition, in the present disclosure, the PUCCH resource set i may be defined such that a larger i is used as the size of the UCI bits is larger, but is not limited thereto. In addition, although an example in which the number of PUCCH resources included in one PUCCH resource set is 8 is shown, the present invention is not limited thereto.

In the following examples, HARQ-ACK transmission is transmitted using PUCCH resources of a predetermined PUCCH resource set 2 (that is, PUCCH resource set 2 is selected based on the size of UCI), but the present invention is not limited thereto.

As shown in the upper right of fig. 4, in PUCCH resource set 1 of TRP1, PUCCH resources 1-1 to 1-8 are set corresponding to DCI of 000 to 111. In the PUCCH resource set 2 of the TRP1, PUCCH resources 1-11 to 1-18 are set corresponding to DCI (more specifically, PUCCH resource indicator field the same in the same drawing below) 000 to 111.

As shown in the lower right of fig. 4, in PUCCH resource set 1 of TRP2, PUCCH resources 2-1 to 2-8 are set corresponding to DCI of 000 to 111. In the PUCCH resource set 2 of the TRP2, PUCCH resources 2-11 to 2-18 are set corresponding to DCI of 000 to 111.

As shown in the upper left of fig. 4, the UE receives DCI1 of PDSCH1 indicating TRP1(DMRS port group 1), and transmits HARQ1 corresponding to the PDSCH 1. Here, the PUCCH resource for HARQ1 may be specified by a specific field (e.g., PUCCH resource indicator field) of DCI 1. For example, in case that the specific field of the DCI1 is 000, the UE may transmit the HARQ1 using resources 1-11 based on the upper right table of fig. 4. Hereinafter, a specific field of DCI may be replaced with a PUCCH resource indicator field.

As shown in the lower left of fig. 4, the UE receives DCI2 of PDSCH2 indicating TRP2(DMRS port group 2), and transmits HARQ2 corresponding to the PDSCH 2. Here, PUCCH resources for HARQ2 may be designated by a specific field (e.g., PUCCH resource indicator field) of DCI 2. For example, in case that the specific field of the DCI2 is 000, the UE may transmit the HARQ2 using resources 2-11 based on the table at the bottom right of fig. 4.

The UE may also be set with a group of TRP-common PUCCH resource sets (which may also be referred to as TRP-independent PUCCH resource sets). With this configuration, an increase in the amount of information for setting the PUCCH resource set can be suppressed. In addition, the set of TRP-common PUCCH resource sets may correspond to PUCCH resource sets 1-4 specified in Rel-15 NR.

Fig. 5 is a diagram showing an example of a set in which a PUCCH resource set common to TRPs is set. In this example, the UE is configured with a set of PUCCH resource sets including PUCCH resource sets 1, 2, and … in common (without distinguishing TRP).

As shown on the right side of fig. 5, in PUCCH resource set 1, PUCCH resources 1 to 8 are set corresponding to DCI of 000 to 111. In the PUCCH resource set 2, PUCCH resources 11 to 18 are set corresponding to DCI of 000 to 111.

As shown in the upper left of fig. 5, the UE receives DCI1 indicating a PDSCH of TRP1(DMRS port group 1), and transmits HARQ1 corresponding to the PDSCH. Here, the PUCCH resource for HARQ1 may be specified by a specific field (e.g., PUCCH resource indicator field) of DCI 1. For example, in case that the specific field of the DCI1 is 000, the UE may transmit the HARQ1 using resource 11 based on the right table of fig. 5.

As shown in the lower left of fig. 5, the UE receives DCI2 indicating a PDSCH of TRP2(DMRS port group 2), and transmits HARQ2 corresponding to the PDSCH. Here, the PUCCH resource for HARQ2 may be specified by a specific field (e.g., PUCCH resource indicator field) of DCI 2. For example, in case that the specific field of the DCI2 is 010, the UE may transmit the HARQ2 using the resource 13 based on the right table of fig. 5.

When a plurality of DCIs are received at a certain TRP, the PUCCH resource of the TRP can be determined by the same method as the above Rel-15 NR (for example, the last (last) DCI of the TRP is selected).

[ multiple PUCCH/PUSCH modifications per slot ]

Even when multi-TRP transmission (NCJT) is set, a UE that has instantaneously received a PDSCH corresponding to single TRP transmission can transmit an HARQ-ACK corresponding to the PDSCH using a PUCCH resource according to the PUCCH resource determination rule of rel.15nr.

For example, when a plurality of PDSCHs that partially or completely overlap with each other in at least one of the time domain and the frequency domain are scheduled by one or more DCI, and at least one of the following conditions is satisfied, the UE may determine PUCCH resources for HARQ-ACKs corresponding to the plurality of PDSCHs, as in rel.15:

only one DMRS port group is indicated for the multiple PDSCHs,

the TCI states (Transmission Configuration Indication states) for the multiple PDSCHs are the same, or the multiple PDSCHs conform to a specific QCL relationship (e.g., QCL type D (QCL-D)).

In addition, this case is essentially no longer a split HARQ-ACK transmission. The UE may include HARQ-ACKs for multiple PDSCHs for each TRP in one PUCCH/PUSCH transmitted.

Fig. 6 is a diagram showing an example of setting a plurality of groups of PUCCH resource sets. This example is similar to fig. 4, and the same contents will not be described repeatedly. In this example, the TCI states of PDSCH1 and PDSCH2 are the same, and the UE can assume that they are transmitted from substantially a single TRP.

In this case, the PUCCH resource may be determined by the same method as the above Rel-15 NR (for example, the last (last) DCI of DCI1 and DCI2 is selected). In this example, the UE may select DCI2 as DCI for deciding a PUCCH resource, and transmit HARQ2 (and HARQ1) using resources 2 to 11 based on a specific field (000) of DCI2 and a table at the bottom right of fig. 6 (a table corresponding to TRP 2).

When at least one of the above conditions is satisfied, a PUCCH resource for HARQ-ACK corresponding to the plurality of PDSCHs may be determined based on a group with the smallest group ID (or TRP ID) among groups of the set PUCCH resource set.

Fig. 7 shows an example of setting a plurality of groups of PUCCH resource sets. This example is similar to fig. 6, and the same contents will not be described repeatedly. In this example, the DCI2 is selected as the DCI for determining the PUCCH resource, which is similar to fig. 6. Fig. 6 is different from that in fig. 6 in that a PUCCH resource is determined from TRP1 resources corresponding to the smallest group ID. The UE may transmit HARQ1 (and HARQ2) with resources 1-11 based on a specific field (═ 000) of DCI2 and the upper right table of fig. 7 (the table corresponding to TRP 1).

In addition to the group of the PUCCH resource set of rel.15 (the group of the PUCCH resource set not associated with a TRP), the UE may be set with a group of the PUCCH resource set for each TRP. In this case, the UE may decide PUCCH resources for transmitting a disjoint HARQ-ACK, which is a disjoint HARQ-ACK for multiple PDSCHs of NCJT, based on a group of PUCCH resource sets per TRP.

On the other hand, the UE may decide PUCCH resources for transmitting HARQ-ACKs for multiple PDSCHs that are not NCJT based on a group of PUCCH resource sets that are not associated with TRP.

Fig. 8 is a diagram showing an example of setting a plurality of groups of PUCCH resource sets. This example is similar to fig. 7, and the same contents will not be described repeatedly. In this example, the difference from fig. 7 is that not only a group of a PUCCH resource set for TRP1/2 but also a group of a PUCCH resource set common to TRPs (which may be referred to as a PUCCH resource set for single TRP) is set for the UE. The UE may transmit HARQ1 (and HARQ2) with resources 0-11 based on a specific field (═ 000) of DCI2 and the top right table of fig. 7 (the table corresponding to a single TRP).

On the other hand, the UE may decide PUCCH resources for transmitting HARQ-ACKs for multiple PDSCHs that are not NCJT based on a group of PUCCH resource sets that are not associated with TRP.

Fig. 9 is a diagram showing an example of a set in which a PUCCH resource set common to TRPs is set. This example is similar to fig. 5, and the same contents will not be described repeatedly. In this example, the TCI states of PDSCH1 and PDSCH2 are the same, and the UE can assume that these are transmitted from substantially a single TRP.

In this case, the PUCCH resource may be determined by the same method as the above Rel-15 NR (for example, the last (last) DCI of DCI1 and DCI2 is selected). In this example, the UE may select DCI2 as DCI for deciding a PUCCH resource, and transmit HARQ1 (and HARQ2) using resource 13 based on a specific field (010) of DCI2 and a table on the right of fig. 9 (a table common to TRPs).

[ spatial relationship information ]

The UE may be set with Spatial Relationship Information (SRI) in PUCCH setting (PUCCH-configuration) units. The spatial relationship information set by the PUCCH setting can be applied to all PUCCH resources set by the PUCCH setting.

When one PUCCH/PUSCH is transmitted per slot, the UE can determine SRI for each PUCCH/PUSCH in the same manner as Rel-15 NR. For example, in the scenario as in fig. 3A, the UE may assume that: the PUCCH and Synchronization Signal Block (SSB) of HARQ1 for transmission slot # m #0 is QCL, and the PUCCH and SSB #10 of HARQ2 for transmission slot # m +1 are QCL.

Considering a case where a plurality of PUCCHs/PUSCHs are transmitted per slot, the UE may be activated with spatial relationship information of the plurality of PUCCHs using one or more MAC Control elements (MAC CEs) (e.g., PUCCH spatial relationship activation/deactivation MAC CEs).

The UE may assume that the spatial relationship information of the activated PUCCH corresponds to the DMRS port groups in an ascending or descending order. That is, it is conceivable that the spatial relationship information of the PUCCH to be activated and the DMRS port groups are one-to-one corresponding from small to large when they are arranged in an ascending order or a descending order, respectively.

The UE may assume that the SRI ID of the smallest PUCCH that is activated (the "PUCCH-spatialrelalationlnfoid" of RRC) corresponds to the smallest DMRS port group ID. For example, in a case where both SRI ID of PUCCH is activated 3 and 5, the UE may consider QCL based on SRI ID of PUCCH 3 for DMRS port group 1, and may consider QCL based on SRI ID of PUCCH 5 for DMRS port group 2.

In addition, in the case where a condition for dynamic backoff to a single TRP (1TRP) is satisfied, the UE may assume a specific SRI ID (e.g., a minimum active SRI ID, a maximum active SRI ID) for the QCL of the 1 TRP.

Here, in the present disclosure, the condition for dynamic backoff to 1TRP may be, for example, a case where the UE is scheduled with one or more DCI to have a plurality of partially or completely overlapping PDSCHs in at least one of the time domain and the frequency domain, and at least one of the following conditions is satisfied.

Only one DMRS port group is indicated for the multiple PDSCHs,

the TCI states for the multiple PDSCHs are the same, or the multiple PDSCHs conform to a particular QCL relationship (e.g., QCL-D).

The UE may be set to the SRI group for each TRP. For example, the UE may be set with a plurality of SRI groups through RRC signaling, and one SRI is activated with the MAC CE for each SRI group. In this case, it is preferable that at least one of information for determining the SRI group (e.g., SRI group ID) and information for determining the TRP (e.g., TRP ID) is contained in the MAC CE.

For example, the UE may set SRI group 1 for DMRS port group 1 and activate one SRI (e.g., {0,1, …,63}) included in SRI group 1 using the MAC CE. Further, the UE may set SRI group 2 for DMRS port group 2 and activate one of the SRIs (e.g., {0,1, …,63}) included in SRI group 2 using the MAC CE.

In addition, when the condition for dynamic fallback to 1TRP is satisfied, the UE may assume a specific SRI group (for example, an SRI group corresponding to the smallest SRI group ID, an SRI group corresponding to the largest SRI group ID) for the QCL of 1 TRP.

In addition to the SRI group set for each TRP, the UE may be set with an SRI group common to the TRPs (may be referred to as an SRI group not associated with the TRP, an SRI group for a single TRP, or the like), or may be set with one SRI (may be referred to as a default SRI, an SRI for fallback, or the like).

In addition, when the condition of dynamic fallback to 1TRP is satisfied, the UE may assume an SRI group common to the 1TRP for the QCL of the TRP, or may assume the default SRI.

According to the first embodiment described above, it is possible to appropriately control the transmission of the HARQ-ACK.

In the first embodiment, an example of a multi-PDCCH is shown, but a single PDCCH may be used. In this case, the number of bits of the PUCCH resource indicator field included in the single PDCCH may be increased compared to the number of bits in the multiple PDCCH. For example, if the PUCCH resource indicator field in the multiple PDCCH is 3 bits, the PUCCH resource indicator field of the single PDCCH may represent 3 bits × the number of TRPs (e.g., 6 bits). The UE may envisage PUCCH resources indicating different TRPs for every 3 bits. Thus, even in the case of a single PDCCH, the PUCCH resource of each TRP can be specified by a portion of each bit.

< second embodiment >

The second embodiment relates to a joint HARQ-ACK transmission. Each HARQ-ACK included in the joint HARQ-ACK corresponds to a different PDSCH (code word), and can be transmitted using at least one of the PUCCH and the PUSCH. The UE transmits the joint HARQ-ACK to one TRP.

The multiple PDSCHs corresponding to the joint HARQ-ACK may be transmitted simultaneously from the TRPs or may be transmitted at different timings. The PDSCH may be scheduled on a single PDCCH or on multiple PDCCHs.

Fig. 10 is a diagram illustrating an example of a flow of the joint HARQ-ACK. In this example, the UE receives DCI1 and DCI2 constituting multiple PDCCHs from TRP1 and TRP2, respectively. Further, the UE receives PDSCH1(CW1) transmitted from TRP1 based on DCI1 and receives PDSCH2(CW2) transmitted from TRP2 based on DCI 2.

The UE transmits a HARQ including HARQ1 for PDSCH1 and HARQ2 for PDSCH2 to TRP 1. In addition, the transmission destination of the HARQ may be TRP 2.

The UE may assume that the TRP of the transmission destination of the joint HARQ-ACK is a TRP that meets one of the following conditions or a combination of these conditions:

a specific TRP (e.g., the TRP with the smallest TRP ID or the TRP with the largest TRP ID) among the plurality of PDSCHs that carry out NCJT or the TRPs that schedule DCIs thereof is transmitted,

the TRP indicated by a certain DCI,

TRP corresponding to DCI at a specific timing (for example, first and last) among DCIs of a plurality of PDSCHs performing NCJT is scheduled,

scheduling TRP corresponding to the last (last) DCI indexed and determined in the same manner as Rel-15 among DCI of multiple PDSCHs performing NCJT.

The joint HARQ-ACK may be transmitted in one slot (that is, with one PUCCH/PUSCH per slot).

Fig. 11 is a diagram illustrating an example of PUCCH resources for joint HARQ-ACK for a single PDCCH. This example is similar to fig. 5, and the same contents will not be described repeatedly. The difference between this example and fig. 5 is that without DCI2, PDSCH1 and PDSCH2 are scheduled with DCI 1.

In this case, the PUCCH resource can be determined by the same method as the above Rel-15 NR. In this example, the UE may select DCI1 as DCI for determining a PUCCH resource, and transmit HARQ (HARQ1 and HARQ2) using resource 13 based on a specific field (000) of DCI1 and the table on the right in fig. 11 (TRP common table).

Fig. 12 is a diagram showing an example of PUCCH resources for joint HARQ-ACK for multiple PDCCHs. This example is similar to fig. 11, and the same contents will not be described repeatedly. The difference between this example and fig. 11 is that there is DCI2, PDSCH1 is scheduled by DCI1 and PDSCH2 is scheduled by DCI 2.

In this example, the PUCCH resource may be determined by the same method as the above Rel-15 NR (e.g., the last (last) DCI of DCI1 and DCI2 is selected). In this example, the UE may select DCI2 as DCI for determining a PUCCH resource, and transmit HARQ (HARQ1 and HARQ2) based on a specific field (010) of DCI2 and a table on the right side of fig. 12 (a table common to TRPs) in TRP 1.

In the case of multiple PDCCH, from among DCI received in TRP having smaller TRP ID, PUCCH resources can be determined based on DCI determined by the above-described rel.15nr method. When the backhaul delay between the TRPs is relatively large, it may be difficult to control the determination of the PUCCH resource for one TRP using the DCI of another TRP (for example, the ARI included in the DCI, the CCE index of the DCI, and the like). Therefore, if the PUCCH resource of a specific TRP (for example, the TRP of the smallest TRP ID) is always determined using the DCI of the specific TRP, control is easy.

Fig. 13 is a diagram illustrating an example of PUCCH resources for joint HARQ-ACK for multiple PDCCHs. This example is similar to fig. 12, and the same contents will not be described repeatedly. The difference between this example and fig. 12 is that DCI1, which is the last DCI of the DCIs of TRP1, is used instead of DCI2 when determining the PUCCH resource of TRP 1.

In this example, the UE may select DCI1 as DCI for determining a PUCCH resource, and transmit HARQ (HARQ1 and HARQ2) based on a specific field (000) of DCI2 and a table on the right side of fig. 13 (TRP common table) in TRP1 corresponding to the smallest TRP ID.

According to the second embodiment described above, transmission of the joint HARQ-ACK can be appropriately controlled.

< third embodiment >

The UE may transmit HARQ-ACK through an independent (or different) HARQ-ACK codebook (hereinafter, also referred to as HARQ codebook) per TRP. In this case, HARQ-ACK feedback can be achieved with low overhead.

On the other hand, when one DCI in multiple PDCCHs is missed, it is preferable to transmit HARQ-ACKs for respective TRPs using a common HARQ codebook in order to suppress the disparity of the number of bits for HARQ-ACKs between the NW and the UE. Hereinafter, a common HARQ codebook will be described in a third embodiment.

< semi-static HARQ codebook >

First, an example of a semi-static HARQ codebook (which may also be referred to as a Type-1 HARQ-ACK codebook) will be described. Fig. 14A and 14B are diagrams showing an example of a semi-static HARQ codebook. This example corresponds to a case where the UE should feed back the HARQ-ACK of the first bit number (for example, 2 bits) for the first TRP (TRP1) and the HARQ-ACK of the second bit number (for example, 2 bits) for the second TRP (TRP 1).

As shown in fig. 14A, in case of a joint HARQ-ACK transmission, the UE may transmit HARQ-ACK of the first number of bits + the second number of bits (e.g., 2+2 ═ 4 bits) to TRP1 or TRP 2.

As shown in fig. 14B, in case of separate HARQ-ACK transmission, the UE may transmit a first HARQ-ACK of a first number of bits + a second number of bits (e.g., 2+2 ═ 4 bits) to the TRP1, and transmit a second HARQ-ACK of the same contents as the first HARQ-ACK to the TRP 2.

< dynamic HARQ codebook >

Next, an example of a dynamic HARQ codebook (which may also be referred to as a Type-2 HARQ-ACK codebook) will be described. One or more DCIs for scheduling each PDSCH of the multiple PDSCHs may include a DL allocation Index (Downlink Assignment Index (Indicator)) in the TRP direction. This DAI may also be referred to as DL DAI (Downlink DAI). Here, the DAI may include at least one of a count DAI (counter DAI) and a total DAI (total DAI).

The count DAI may represent a count value of downlink transmissions (e.g., at least one of PDSCH, data, transport blocks) scheduled during a specific period. For example, the count DAI within the DCI scheduling the PDSCH within the specific period may indicate a number counted at least in the TRP region (e.g., TRP ID order) within the specific period.

The total DAI may represent an aggregate value (total) of scheduled downlink transmissions within a specific period. For example, the total DAI in the DCI for scheduling the PDSCH in a predetermined time element (e.g., PDCCH monitoring opportunity) in the specific period may indicate the total number of PDSCHs of all TRPs scheduled until the predetermined time element (also referred to as a point, a timing, or the like) in the specific period.

Here, in the present disclosure, the above-mentioned specific period related to the DAI may be one or more symbols, one or more slots, and the like. In addition, in the present disclosure, the downlink transmission scheduled in a specific period may be interchanged with multiple PDSCHs.

When part of a plurality of DCIs transmitted from a plurality of TRPs is missed (not received), the UE can recognize that part of the plurality of DCIs is not received.

When the DCI scheduling each PDSCH of the multiple PDSCHs includes at least one of the count DAI and the total DAI, the UE may assume close cooperation between TRPs transmitting the multiple PDSCHs or connection using a non-ideal backhaul (non-ideal backhaul). This is because, in order to emit DAI in the TRP direction, DCI in which one TRP grasps another TRP is preferable.

The UE may transmit a UL DAI (Uplink DAI) to the network in association with a PUCCH or PUSCH transmitting a joint HARQ-ACK or a separate HARQ-ACK. The UL DAI may be transmitted without receiving the DL DAI described above, or may be transmitted with receiving the DL DAI described above.

Here, the UL DAI may be DCI detected by the UE, and may be information on the number of DCI transmitted in downlink in a scheduling specific period (for example, the detected number of DCI). The information may be a quantity value of the DCI, or information (may be expressed by 1-bit information) on whether the quantity of the DCI coincides with a value of a total DAI notified from the network.

Here, the value of the total DAI may be notified to the UE using higher layer signaling, physical layer signaling (for example, DCI scheduling at least one of multiple PDSCHs within the predetermined period), or a combination thereof.

The UL DAI may be explicitly transmitted or implicitly transmitted using at least one of:

(1) a part of UCI bits of PUCCH/PUSCH,

(2) at least a portion of the DMRS modulated signal of the PUCCH/PUSCH,

(3) a sequence utilized in transmission of at least a part or all of the DMRS of the PUCCH/PUSCH,

(4) a resource (e.g., physical resource) used for transmission of at least a part or all of the DMRS or UCI of the PUCCH/PUSCH.

For example, in the case of (1) above, the UE may include bits (e.g., 1 bit) corresponding to the UL DAI in the PUCCH/PUSCH for transmitting the joint HARQ-ACK or the HARQ-ACK.

In the case of (2) above, the UE may modulate (e.g., bpsk (binary Phase Shift keying) modulation or qpsk (quadrature Phase Shift keying) modulation) at least a part of DMRS resources (e.g., Resource Elements (REs) and Physical Resource Blocks (PRBs)) of a PUCCH/PUSCH for transmitting the joint HARQ-ACK or the HARQ-ACK.

In the case of (3) above, the UE may implicitly transmit the UL DAI of the first value by transmitting the first sequence in the DMRS resource of the PUCCH/PUSCH for transmitting the joint HARQ-ACK or the separate HARQ-ACK, or may implicitly transmit the UL DAI of the second value by transmitting the second sequence different from the first sequence.

Here, the second sequence may be a sequence generated by calculating (for example, adding, subtracting, multiplying, or dividing) a specific offset for at least one of a Cyclic Shift (CS), a sequence index, and an Orthogonal Code (OCC) of the first sequence. The second sequence may be a DMRS sequence generated by +6 for the CS index of the first sequence.

In the case of (4) above, the UE may implicitly transmit the UL DAI of the first value using the resource indicated from the network as the resource of the PUCCH/PUSCH for transmitting the joint HARQ-ACK or the split HARQ-ACK, or implicitly transmit the UL DAI of the second value using the resource to which a specific offset is applied from the indicated resource.

The specific offset in (3) or (4) above may be notified to the UE by higher layer signaling, physical layer signaling (for example, DCI that schedules at least one of multiple PDSCHs within the predetermined period), or a combination thereof.

According to the third embodiment described above, even when part of DCI scheduling multiple PDSCHs is not received in the UE, the number of HARQ-ACK bits for the multiple PDSCHs can be recognized exactly between the network and the UE.

< other embodiment >

The type of HARQ-ACK transmission (whether with a split HARQ-ACK transmission or a joint HARQ-ACK transmission) that the UE applies to multiple PDSCHs may be decided based on at least one of:

set by higher layer signaling (e.g., the UE can assume to utilize a separate HARQ-ACK transmission if a joint HARQ-ACK transmission is not set),

dynamically specified by the DCI (e.g., the type of HARQ-ACK transmission to utilize may be specified using a new bit field or an existing bit field),

it is decided by PUCCH resources of a plurality of HARQ-ACKs for each of a plurality of PDSCHs (for example, it may be determined that a split HARQ-ACK transmission is performed if their PUCCH resources do not overlap in the time/frequency domain, and a joint HARQ-ACK transmission is performed otherwise (that is, partially or completely overlap).

Fig. 15A to 15D are diagrams showing an example of determining the type of HARQ-ACK transmission based on PUCCH resources. Fig. 15A and 15B show examples of determining to use the separate HARQ-ACK transmission, and fig. 15C and 15D show examples of determining to use the joint HARQ-ACK transmission.

The time resources of HARQ1 and HARQ2 in fig. 15A do not overlap at all. In this case, the UE may transmit separate HARQ-ACKs in the resources of each HARQ, respectively.

The time resources of HARQ1 and HARQ2 in fig. 15B overlap (HARQ1 is fully contained in the time resources of HARQ 2). When PUCCH-PUCCH simultaneous transmission is enabled, the UE may transmit the HARQ-ACK separately in each HARQ resource, otherwise, may transmit the HARQ-ACK using one resource (e.g., a larger HARQ2 resource) and discard the other resource (e.g., a HARQ1 resource).

The time resources of HARQ1 and HARQ2 in fig. 15C are identical. In this case, the UE may send a joint HARQ-ACK in the resources of any one HARQ.

In fig. 15D, the HARQ1 and HARQ2 start symbols of the time resource coincide with each other. In this case, the UE may send a joint HARQ-ACK in the resources of any one HARQ.

In the present disclosure, an example of transmitting UCI (HARQ-ACK) using PUCCH is mainly explained, but is not limited thereto. The present disclosure can also be applied to a case of transmitting UCI using PUSCH (UCI on PUSCH). The PUSCH may be a PUSCH scheduled by DCI, or may be a grant PUSCH. The spatial relationship information of the PUCCH can be replaced with spatial relationship information of a Sounding Reference Signal (SRS) for the PUSCH.

Further, it is conceivable to apply one of Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), and Space Division Multiplexing (SDM) or a combination thereof to the multi-PUCCH in the present disclosure.

Furthermore, the HARQ-ACK of the present disclosure may be replaced with any UCI. In this case, the PUCCH resource may be set through RRC signaling. For example, the UE may use a resource set by RRC as a PUCCH resource for CSI reporting.

In addition, in the present disclosure, which TRP the DCI schedules may be explicitly specified by a DCI bit field. In addition, when at least one of the CORESET, the search space set, the QCL, the TCI status, and the like corresponding to the TRP is set in advance, the UE may determine which TRP the DCI schedules based on at least one of the CORESET, the search space set, the QCL, the TCI status, and the like in which the DCI is detected.

In addition, although an example in which a plurality of pieces of DCI (DCI1, DCI2) are detected in different symbols is shown in a plurality of figures such as fig. 4, the plurality of pieces of DCI may be detected in the same symbol. In the case where the UE has a capability (UE capability) capable of detecting a plurality of DCIs different in QCL in the same symbol (or reports a case of supporting the capability), the plurality of DCIs can be detected in the same symbol.

(Wireless communication System)

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

Fig. 16 is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using LTE (Long Term Evolution) standardized by 3GPP (Third Generation Partnership Project), 5G NR (5th Generation mobile communication system New Radio), and the like.

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

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

The wireless communication system 1 can support Dual connection between a plurality of base stations within the same RAT (for example, Dual connection of a MN and a base station (gNB) whose SN is NR (NR-NR Dual Connectivity (NN-DC))).

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

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

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

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

The plurality of base stations 10 may be connected by wire (e.g., optical fiber complying with Common Public Radio Interface (CPRI), X2 Interface, or the like) or wireless (e.g., NR communication). For example, in the case where NR communication is used as a Backhaul between the base station 11 and the base station 12, the base station 11 corresponding to an upper station may be referred to as an IAB (Integrated Access Backhaul) host, and the base station 12 corresponding to a Relay station (Relay) may be referred to as an IAB node.

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

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

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

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

In the radio communication system 1, a Downlink Shared Channel (PDSCH), a Physical Downlink Shared Channel (PDCCH), a Broadcast Channel (PBCH), a Physical Broadcast Channel (PDCCH), a Downlink Control Channel (PDCCH), a Physical Downlink Control Channel (PDCCH), etc.) Shared by the user terminals 20 can be used as the Downlink Channel.

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

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

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

In addition, DCI scheduling PDSCH may be referred to as DL allocation, DL DCI, etc., and DCI scheduling PUSCH may be referred to as UL grant, UL DCI, etc. In addition, PDSCH may be replaced with DL data and PUSCH may be replaced with UL data.

A Control Resource SET (core SET) and a search space (search space) may be used for PDCCH detection. CORESET corresponds to searching for DCI resources. The search space corresponds to a search region and a search method of PDCCH candidates (PDCCH candidates). A CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space settings.

One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels (aggregation levels). The one or more search spaces may be referred to as a set of search spaces. In addition, "search space", "search space set", "search space setting", "search space set setting", "CORESET setting", and the like of the present disclosure may be substituted for one another.

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

In addition, in the present disclosure, a downlink, an uplink, and the like may be expressed without accompanying "link". Note that "Physical" may not be attached to the beginning of each channel.

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

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

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

(base station)

Fig. 17 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface (transmission line interface) 140. The control unit 110, the transmission/reception unit 120, the transmission/reception antenna 130, and the transmission path interface 140 may be arranged in 1 or more number, respectively.

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

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

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

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

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

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

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

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

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

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

The transmission/reception unit 120(RF unit 122) may perform modulation, filtering, amplification, and the like on the baseband signal to a radio frequency band, and transmit the signal of the radio frequency band via the transmission/reception antenna 130.

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

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

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

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

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

Further, the transmission/reception unit 120 may transmit the PDSCH to the user terminal 20. The control unit 110 may control the PDSCH to overlap with a PDSCH transmitted from another base station 10 on at least one of time and frequency resources.

(user terminal)

Fig. 18 is a diagram showing an example of the configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transmission/reception unit 220, and a transmission/reception antenna 230. The control unit 210, the transmission/reception unit 220, and the transmission/reception antenna 230 may be arranged in 1 or more number, respectively.

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

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

The control unit 210 may control generation of signals, mapping, and the like. The control unit 210 can control transmission and reception, measurement, and the like using the transmission and reception unit 220 and the transmission and reception antenna 230. The control unit 210 may generate data, control information, sequences, and the like transmitted as signals and forward to the transmitting and receiving unit 220.

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

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

The transmitting/receiving antenna 230 can be configured by an antenna described based on common knowledge in the technical field of the present disclosure, and can be configured by an array antenna or the like, for example.

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

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

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

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

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

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

On the other hand, the transmission/reception unit 220(RF unit 222) may amplify, filter, demodulate a baseband signal, and the like, a signal of a radio frequency band received by the transmission/reception antenna 230.

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

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

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

Further, control section 210 may receive a first PDSCH (physical Downlink Shared channel) from a first Transmission/reception point (TRP) and a second PDSCH from a second TRP, the second PDSCH overlapping with the first PDSCH in at least one of time and frequency resources. That is, the transmission/reception unit 220 may receive multiple PDSCHs.

The control unit 210 may perform the following control: transmitting a first HARQ-ACK (hybrid Automatic Repeat reQuest acknowledgement) for the first PDSCH to the first TRP, and transmitting a second HARQ-ACK for the second PDSCH to the second TRP.

The control unit 210 may decide resources for transmitting the first HARQ-ACK based on the group of resource sets for the first TRP and decide resources for transmitting the second HARQ-ACK based on the group of resource sets for the second TRP.

Control section 210 may decide both resources for transmitting the first HARQ-ACK and resources for transmitting the second HARQ-ACK based on a group of common resource sets.

When spatial relationship information of a PUCCH (Physical Uplink Control Channel) of a first ID and spatial relationship information of a PUCCH of a second ID having a value greater than the first ID are activated, Control section 210 may perform the following Control: and if the ID of the second TRP is larger than the ID of the first TRP, transmitting the first HARQ-ACK based on the spatial relationship information of the PUCCH with the first ID, and if the ID of the second TRP is less than or equal to the ID of the first TRP, transmitting the first HARQ-ACK based on the spatial relationship information of the PUCCH with the second ID.

The control unit 210 may also assume that the spatial relationship information for the first TRP and the spatial relationship information for the second TRP are individually activated (for example, in the case where an SRI group for each TRP is set).

The control unit 210 may also perform the following control: and transmitting both the first HARQ-ACK for the first PDSCH and the second HARQ-ACK for the second PDSCH to one (for example, only one) of the first TRP and the second TRP.

The control unit 210 may also determine that the TRP for transmitting the first HARQ-ACK and the second HARQ-ACK is a TRP having a smaller ID among the IDs of the first TRP and the second TRP.

The control unit 210 may perform the following control: utilizing a common codebook for transmitting a first HARQ-ACK for the first PDSCH and a second HARQ-ACK for the second PDSCH.

The one or more Downlink control information for scheduling the first PDSCH and the second PDSCH may include a DL Assignment Index (Downlink Assignment Index (Indicator)) (DAI)) in the TRP direction. Control section 210 may determine whether or not a part of the one or more pieces of downlink control information transmitted from the first TRP and the second TRP have not been received (whether or not all pieces of downlink control information have been successfully received) based on the DAI in the TRP direction.

Control section 210 performs control for transmitting the first HARQ-ACK and the second HARQ-ACK and also for explicitly or implicitly transmitting an Uplink DL Assignment Index (UL DAI), where the UL DAI may correspond to information on the number of detected Downlink Control Information (DCI) for PDSCH in a scheduling specific period.

Control section 210 may generate at least a part of a predetermined DMRS (e.g., a DMRS for PUCCH or PUSCH) based on the UL DAI, and may determine at least one of a sequence, a resource, and the like of the DMRS.

(hardware construction)

The block diagrams used in the description of the above embodiments represent blocks in functional units. These functional blocks (structural units) are realized by any combination of at least one of hardware and software. The method of implementing each functional block is not particularly limited. That is, each functional block may be implemented by 1 apparatus physically or logically combined, or may be implemented by a plurality of apparatuses by directly or indirectly (for example, by wire or wireless) connecting two or more apparatuses physically or logically separated from each other. The functional blocks may be implemented in software for the above-described apparatus or apparatuses.

Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, establishment, comparison, assumption, expectation, view, broadcast (broadcasting), notification (notification), communication (communication), forwarding (forwarding), setting (configuration), reconfiguration (reconfiguration), allocation (allocation), and the like. For example, a functional block (a constituent unit) that functions transmission may also be referred to as a transmission unit (transmitting unit), a transmitter (transmitter), or the like. As described above, any of the methods is not particularly limited.

For example, a base station, a user terminal, or the like in one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 19 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 described above 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 addition, in the present disclosure, words such as device, circuit, apparatus, section (section), unit, and the like can be substituted for one another. The hardware configuration of the base station 10 and the user terminal 20 may include 1 or more of each illustrated device, or may be configured without including some devices.

For example, only 1 processor 1001 is shown, but there may be multiple processors. The processing may be executed by 1 processor, or the processing may be executed by 2 or more processors simultaneously, sequentially, or by using another method. The processor 1001 may 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 predetermined software (program) into hardware such as the processor 1001 and the memory 1002, performing an operation by the processor 1001, and controlling communication via the communication device 1004 or controlling at least one of reading and writing of data in the memory 1002 and the storage 1003.

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

The processor 1001 reads 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 based on the program (program code), the software module, the data, and the like. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiments is used. For example, the control unit 110(210) may be implemented by a control program stored in the memory 1002 and operated in the processor 1001, and may be similarly implemented with respect to other functional blocks.

The Memory 1002 is a computer-readable recording medium, and may be configured by at least 1 of ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable EPROM), RAM (Random Access Memory), and other suitable storage media. The memory 1002 may also be referred to as a register, cache, main memory (primary storage), or the like. The memory 1002 can store executable programs (program codes), software modules, and the like for implementing the wireless communication method of an embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium, and may be configured of at least one of a flexible disk, a floppy (registered trademark) disk, an optical magnetic disk (e.g., a Compact Disc ROM (CD-ROM) or the like), a digital versatile disk, a Blu-ray (registered trademark) disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic 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, for example, in order to realize at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, the transmitting/receiving unit 120(220), the transmitting/receiving antenna 130(230), and the like described above may be implemented by the communication device 1004. The transmitting and receiving unit 120(220) may be physically or logically implemented separately as a transmitting unit 120a (220a) and a receiving unit 120b (220 b).

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

Further, the processor 1001, the memory 1002, and the like are connected by a bus 1007 for communicating information. The bus 1007 may be formed using a single bus, or may be formed using a bus different from one device to another.

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), and an FPGA (Field Programmable Gate Array), and a part or all of the functional blocks may be implemented by the hardware. For example, the processor 1001 may be implemented using at least one of these hardware.

(modification example)

In addition, terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, channels, symbols, and signals (signals or signaling) may be substituted for one another. Further, the signal may also be a message. The Reference Signal (Reference Signal) can also be referred to as RS for short and, depending on the applied standard, can also be referred to as Pilot (Pilot), Pilot Signal, etc. Further, 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. The 1 or more periods (frames) constituting the radio frame may also be referred to as subframes. Further, the subframe may be formed of 1 or more slots in the time domain. The subframe may be a fixed time length (e.g., 1ms) independent of a parameter set (Numerology).

Here, the parameter set (Numerology) may be a communication parameter applied to at least one of transmission and reception of a certain signal or channel. The parameter set may indicate, 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 processing performed by the transceiver in the frequency domain, specific windowing processing performed by the transceiver in the Time domain, and the like.

The slot may be formed of 1 or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, or the like) in the time domain. Also, the slot may be a time unit based on a parameter set (Numerology).

A slot may comprise a plurality of mini-slots (mini-slots). Each mini-slot may be composed of 1 or more symbols in the time domain. In addition, a mini-slot may also be referred to as a sub-slot. A mini-slot may be composed of a smaller number of symbols than a slot. PDSCH (or PUSCH) transmitted in a time unit greater than a mini-slot may also be referred to as PDSCH (PUSCH) mapping type a. PDSCH (or PUSCH) transmitted using mini-slots may also be referred to as PDSCH (PUSCH) mapping type B.

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

For example, 1 subframe may also be referred to as a TTI, a plurality of consecutive subframes may also be referred to as a TTI, and 1 slot or 1 mini-slot may also 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 units of TTIs. In addition, the definition of TTI is not limited thereto.

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

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

In addition, 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 smaller than that of the long TTI and equal to or longer than 1 ms.

A Resource Block (RB) is a Resource allocation unit in the time domain and the frequency domain, and may include 1 or more consecutive subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in the RB may be the same regardless of the parameter set, and may be, for example, 12 subcarriers. The number of subcarriers included in the RB may also be decided based on the parameter set.

In addition, an 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 1 TTI, 1 subframe, and the like may be formed of 1 or a plurality of resource blocks.

In addition, 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.

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

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

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

At least one of the set BWPs may be active and the UE may not be supposed to transmit and receive a specified signal/channel outside the active BWP. In addition, "cell", "carrier", and the like in the present disclosure may also be replaced with "BWP".

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 the 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 modified.

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

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

Information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, and chips 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.

Further, the information, signals, etc. may enable at least one of the following outputs: an output from a higher layer (upper layer) to a lower layer (lower layer), and an output from a lower layer to a higher layer. Information, signals, and the like may be input and output via a plurality of network nodes.

The information, signals, and the like to be input and output may be stored in a specific area (for example, a memory) or may be managed by a management table. Information, signals, and the like to be input and output may be overwritten, updated, or added. The information, signals, etc. that are output may also be deleted. The input information, signal, and the like may 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 notification of the Information in the present disclosure may be implemented by physical layer signaling (e.g., Downlink Control Information (DCI), Downlink Control Information), Uplink Control Information (UCI), Uplink Control Information), higher layer signaling (e.g., RRC (Radio Resource Control) signaling, broadcast Information (Master Information Block (MIB)), System Information Block (SIB), etc.), MAC (Medium Access Control) signaling), other signals, or a combination thereof.

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

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

The determination may be made by a value (0 or 1) represented by 1 bit, by a true-false value (Boolean) represented by true (true) or false (false), or by a comparison of values (e.g., with a specific value).

Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by other names, is intended to be broadly interpreted as representing instructions, instruction sets, code segments, program code, programs, subroutines, software modules, applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like.

Further, software, instructions, information, etc. may be transmitted or received via a transmission medium. For example, in a case where software is transmitted from a website, a server, or another remote source using at least one of a wired technology (coaxial cable, optical cable, twisted pair, Digital Subscriber Line (DSL)), or the like) and a wireless technology (infrared ray, microwave, or the like), at least one of these wired technology and wireless technology is included in the definition of transmission medium.

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

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

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

A base station can accommodate 1 or more (e.g., three) cells. In the case where a base station accommodates a plurality of cells, the coverage area of the base station as a whole 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 Remote Radio Head (RRH)) for indoor use. The term "cell" or "sector" refers to a part or all of the coverage area of at least one of a base station and a base station subsystem that performs communication services in the coverage area.

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

A mobile station is also sometimes called a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, or some other suitable terminology.

At least one of the base station and the mobile station may be referred to as a transmitting apparatus, a receiving apparatus, a wireless communication apparatus, or the like. At least one of the base station and the mobile station may be a device mounted on the mobile body, the mobile body itself, or the like. The moving body may be a vehicle (e.g., an automobile, an airplane, etc.), may be an unmanned moving body (e.g., an unmanned aerial vehicle, an autonomous automobile, 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 during a communication operation. 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.

In addition, the base station in the present disclosure may also be replaced with a user terminal. For example, the embodiments and modes of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between a plurality of user terminals (for example, D2D (Device-to-Device), V2X (Vehicle-to-event), and the like may be used). In this case, the user terminal 20 may have the function of the base station 10. The terms "uplink" and "downlink" may be replaced with terms (e.g., "side") corresponding to inter-terminal communication. For example, an uplink channel, a downlink channel, or the like may be replaced with a side channel (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 a configuration having the functions of the user terminal 20.

In the present disclosure, it is assumed that the operation performed by the base station is sometimes performed by an upper node (upper node) thereof, depending on the case. In a network including 1 or more network nodes (network nodes) having a base station, it is obvious that 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, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), or the like is considered, but not limited thereto), or a combination thereof.

The aspects and embodiments described in the present disclosure may be used alone, or in combination, or may be switched with execution. Note that, the processing procedures, sequences, flowcharts, and the like of the respective modes/embodiments described in the present disclosure may be reversed as long as they are not contradictory. For example, elements of the various steps are presented in the order illustrated with respect to the method described in the present disclosure, and are not limited to the specific order presented.

The aspects/embodiments described in the present disclosure may be applied to LTE (Long Term Evolution), LTE-a (LTE-Advanced), LTE-B (LTE-Beyond), SUPER3G, IMT-Advanced, 4G (4th generation Mobile communication System ), 5G (5th generation Mobile communication System, 5th generation Mobile communication System), FRA (Future Radio Access), New-RAT (Radio Access Technology ), NR (New Radio, New wireless trademark), NX (New Radio Access, New wireless Access), FX (Future Radio Access, next generation wireless Access), GSM (registration for Mobile System, Global Mobile communication System, Wi-Mobile communication System, IEEE 802, and Radio Access, wideband Mobile communication System, Radio Access, GSM (registration for Mobile communication System, Radio Access, IEEE 802.16(WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), a system using another appropriate wireless communication method, a next generation system extended based on them, and the like. Furthermore, a plurality of systems (for example, a combination of LTE or LTE-a and 5G) may be combined and applied.

As used in this disclosure, a recitation of "based on" does not mean "based only on" unless explicitly stated otherwise. In other words, the expression "based on" means both "based only on" and "based at least on".

Any reference to the use of "first," "second," etc. terms in this disclosure is not intended to limit the amount or order of those elements as a whole. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, reference to first and second elements does not mean that only two elements may be employed or that the first element must precede the second element in some fashion.

The term "determining" used in the present disclosure sometimes includes various operations. For example, "determining" may be considered "determining" with respect to a decision (judging), calculation (calculating), processing (processing), derivation (deriving), investigation (investigating), retrieval (logging up, search, retrieval) (e.g., a search in a table, database, or other data structure), confirmation (authenticating), and the like.

Further, "determining" may be considered as "determining" reception (e.g., receiving information), transmission (e.g., transmitting information), input (input), output (output), access (e.g., accessing data in a memory), and the like.

Further, "judgment (decision)" may be regarded as "judgment (decision)" performed on solution (resolving), selection (selecting), selection (breathing), establishment (evaluating), comparison (comparing), and the like. That is, "judgment (decision)" may be regarded as "judgment (decision)" performed on some operation.

The "judgment (decision)" may be replaced with "assumption", "expectation", "consideration", and the like.

The terms "connected", "coupled", or all variations thereof used in the present disclosure mean all connections or couplings, directly or indirectly, between two or more elements, and can include a case where 1 or more intermediate elements exist between two elements that are "connected" or "coupled" to each other. The combination or connection between the elements may be physical, logical, or a combination thereof. For example, "connected" may also be replaced with "accessed".

In the case of connecting two elements in the present disclosure, it can be considered that the two elements are "connected" or "combined" with each other by using one or more electric wires, cables, printed electrical connections, etc., and by using electromagnetic energy having a wavelength of a wireless frequency domain, a microwave region, a light (both visible light and invisible light), etc., as a few non-limiting and non-exhaustive examples.

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

Where the terms "comprising", "including" and "containing" and variations thereof are used in this disclosure, these terms are intended to be inclusive in the same way as the term "comprising". Further, the term "or" as used in this disclosure means not a logical exclusive or.

In the present disclosure, where articles are added by translation, such as "a," "an," and "the" in english, the present disclosure may include instances where the noun after the articles is plural.

Although the invention according to the present disclosure has been described in detail above, it is obvious 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 on the invention related to the present disclosure.