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 原田浩树 村山大辅 于 2019-02-14 设计创作，主要内容包括：在NR-U载波中适当地考虑与SSB有关的QCL设想。本公开的一方式所涉及的用户终端的特征在于,具有：接收单元,接收同步信号块(Synchronization Signal Block(SSB))；以及控制单元,基于所述SSB所包含的广播信道(物理广播信道(Physical Broadcast Channel(PBCH))的解调用参考信号(DeModulation Reference Signal(DMRS)),取得实效SSB索引,并从所述PBCH的有效载荷取得被发送的所述实效SSB索引的数量的信息、以及发现参考信号(Discovery Reference Signal(DRS))发送窗口内的包含所述SSB的SSB突发的起始位置索引中的至少一方。(QCL assumptions about SSBs are considered in the NR-U carriers as appropriate. A user terminal according to an aspect of the present disclosure includes: a reception unit that receives a Synchronization Signal Block (SSB); and a control unit configured to acquire an effective SSB index based on a DeModulation Reference Signal (DMRS) for a Broadcast Channel (Physical Broadcast Channel (PBCH)) included in the SSB, and acquire at least one of information on the number of transmitted effective SSB indexes and a start position index of an SSB burst including the SSB in a Discovery Reference Signal (DRS) transmission window from a payload of the PBCH.)

1. A user terminal, comprising:

a reception unit that receives a Synchronization Signal Block (SSB); and

and a control unit configured to acquire an effective SSB index based on a DeModulation Reference Signal (DMRS) of a Broadcast Channel (Physical Broadcast Channel (PBCH)) included in the SSB, and acquire at least one of information on the number of transmitted effective SSB indexes and a start position index of an SSB burst including the SSB in a Discovery Reference Signal (DRS) transmission window from a payload of the PBCH.

2. The user terminal of claim 1,

the control unit applies soft combining to the decoding of the PBCH within the SSB burst.

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

a step of receiving a Synchronization Signal Block (SSB); and

and a step of acquiring an effective SSB index based on a DeModulation Reference Signal (DMRS) of a Broadcast Channel (Physical Broadcast Channel (PBCH)) included in the SSB, and acquiring information on the number of transmitted effective SSB indexes and at least one of a start position index of an SSB burst including the SSB in a Discovery Reference Signal (DRS) transmission window from a payload of the PBCH.

Technical Field

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

Background

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

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

In a conventional LTE system (e.g., rel.8-12), standardization is performed assuming exclusive operation in a frequency band (also referred to as a licensed band (licensed band), a licensed carrier (licensed carrier), a licensed component carrier (licensed CC), or the like) licensed to a communication carrier (operator). As the grant CC, for example, 800MHz, 1.7GHz, 2GHz, or the like is used.

In addition, in the conventional LTE system (e.g., rel.13), in order to expand a frequency band, use of a frequency band (also referred to as unlicensed band, unlicensed carrier, and unlicensed cc) different from the above-described licensed band is supported. As the unlicensed band domain, for example, a 2.4GHz band and a 5GHz band which can use Wi-Fi (registered trademark) or Bluetooth (registered trademark) are conceivable.

In rel.13, Carrier Aggregation (CA) is supported that integrates carriers (CC) of the licensed band domain and carriers (CC) of the unlicensed band domain. Communication using the authorized band domain and the unauthorized band domain is referred to as License-Assisted Access (LAA).

Documents of the prior art

Non-patent document 13 GPP 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

The use of an unlicensed band is also being studied in NR. Listening (also referred to as Listen Before Talk (LBT)) or the like) is performed Before transmission of data in the unlicensed band domain.

Further, in NR, a Synchronization Signal (SS)/Physical Broadcast CHannel (PBCH) block (SS block (SSB)) is used. A User Equipment (e.g., User Equipment (UE)) may be set with a higher layer parameter (e.g., may also be referred to as Radio Resource Control (RRC) parameter) "SSB-positioninglnburst") related to a transmission unit (which may also be referred to as an SS burst, an SS burst set, or simply a burst, etc.) of a plurality of aggregated SSBs.

However, in the case where the SSB transmitted semi-statically is notified using SSB-positioninburst, research has not been advanced as far as the UE appropriately judges the Quasi-Co-location (qcl) between SSB indexes in consideration of LBT failure. Also, when SSB-positioningburst cannot be used, no research has been made on the assumption that the UE appropriately determines QCL between SSB indexes in consideration of LBT failure. Unless these are explicitly defined, the PDCCH cannot be appropriately monitored, and the communication throughput may be lowered.

Accordingly, an object of the present disclosure is to provide a user terminal and a wireless communication method capable of appropriately considering QCL assumption related to SSB in an NR-U carrier.

Means for solving the problems

A user terminal according to an aspect of the present disclosure includes: a reception unit that receives a Synchronization Signal Block (SSB); and a control unit configured to acquire an effective SSB index based on a DeModulation Reference Signal (DMRS) of a Broadcast Channel (Physical Broadcast Channel (PBCH)) included in the SSB, and acquire at least one of information on the number of transmitted effective SSB indexes and a start position index of an SSB burst including the SSB in a Discovery Reference Signal (DRS) transmission window from a payload of the PBCH.

Effects of the invention

According to an aspect of the present disclosure, QCL assumptions relating to SSBs can be properly considered in NR-U carriers.

Drawings

Fig. 1 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for OSI and SSB in Rel-15 NR.

Fig. 2 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for paging and SSB in Rel-15 NR.

Fig. 3A and 3B are diagrams showing an example of extension of the SSB transmission candidate position.

Fig. 4 is a diagram showing another example of extension of the SSB transmission candidate position.

Fig. 5A and 5B are diagrams illustrating an example of problems assumed by the QCL of the SSB.

Fig. 6 is a diagram showing an example of QCL assumption between SSB indexes in one embodiment.

Fig. 7 is a diagram showing another example of QCL assumption between SSB indexes in one embodiment.

Fig. 8 is a diagram showing another example of QCL assumption between SSB indexes in one embodiment.

Fig. 9 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for paging and an SSB in one embodiment.

Fig. 10A to 10C are diagrams showing specific examples of the effective SSB index according to an embodiment.

Fig. 11A to 11C are diagrams showing specific examples of the effective SSB index according to an embodiment.

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

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

Fig. 14 is a diagram showing an example of a functional configuration of a user terminal according to an embodiment.

Fig. 15 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment.

Detailed Description

< unlicensed band Domain >

In an unlicensed band (e.g., 2.4GHz band, 5GHz band, and 6GHz band), it is assumed that a plurality of systems such as a Wi-Fi system and a LAA-supporting system (LAA system) coexist, and collision avoidance and/or interference control of transmission between the plurality of systems is required.

For example, in a Wi-Fi system using an unlicensed band, Carrier Sense Multiple Access/Collision Avoidance (CSMA)/Collision Avoidance (CA) is employed for Collision Avoidance and/or interference control. In CSMA/CA, a specific time Distributed access Inter Frame Space (DIFS) is set before transmission, and a transmitting apparatus performs data transmission after confirming (carrier sense) that there is no other transmission signal. After data transmission, the receiving apparatus waits for an ACK (ACKnowledgement) from the receiving apparatus. When the ACK cannot be received within a specific time, the transmission apparatus determines that collision has occurred and performs retransmission.

In LAA of the conventional LTE system (e.g., rel.13), a data transmitting apparatus performs monitoring (also referred to as Listen Before Talk (LBT)), Clear Channel Assessment (CCA)), carrier sensing, Channel sensing, or a Channel access operation, for example) to confirm whether or not there is transmission of other apparatuses (e.g., a base station, a user terminal, a Wi-Fi apparatus, and the like) Before transmission of data in an unlicensed band.

The transmitter may be a base station (e.g., a gbnodeb (gnb)) in a Downlink (DL) and a User terminal (e.g., a User Equipment (UE)) in an Uplink (UL), for example. The receiving apparatus that receives data from the transmitting apparatus may be a UE in the DL or a base station in the UL, for example.

In LAA of the conventional LTE system, the transmitting apparatus starts data transmission after a certain period (for example, immediately after or during backoff) from when the LBT detects that there is no transmission from another apparatus (idle state).

The NR system using the unlicensed band domain may also be referred to as an NR-unlicenced (u) system, an NR LAA system, or the like. Dual Connectivity (DC) of the authorized band domain and the unauthorized band domain, Stand-alone (sa) of the unauthorized band domain, and the like may also be employed in the NR-U.

The nodes (e.g., base stations, UEs) in the NR-U coexist with other systems or other operators and thus start transmitting after confirming that the channel is idle (idle) through LBT.

In the NR-U system, when the LBT result is idle (LBT-idle), the base station or the UE obtains a Transmission Opportunity (TxOP) and transmits the LBT result. In case that the LBT result is busy (LBT-busy), the base station or the UE does not transmit. The Time of the transmission opportunity is also referred to as a Channel Occupancy Time (COT).

In addition, LBT-idle may also be replaced by LBT success (LBT success). LBT-busy may also be replaced by a failure of LBT (LBT failure).

<SSB>

In NR, a Synchronization Signal/Broadcast Channel (Synchronization Signal/Physical Broadcast Channel (SS/PBCH)) block is utilized. The SS/PBCH block may be a Signal block including a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSs), a Broadcast Channel (Physical Broadcast Channel (PBCH)) (and a DeModulation Reference Signal (DMRS)) for PBCH). The SS/PBCH Block may also be referred to as a Synchronization Signal Block (SSB).

In the Rel-15 NR, a PDCCH monitoring operation for receiving Other System Information (OSI)) and paging (paging) is specified. The OSI may correspond to System Information other than the Minimum System Information (Remaining Minimum System Information (RMSI)).

For example, when the ID of the search space for OSI or paging is 0 (that is, when the UE monitors the PDCCH for OSI or paging in the search space 0(search space # 0)), the monitoring opportunity (PDCCH monitoring opportunity) of the PDCCH may be the same as the PDCCH monitoring opportunity for the System Information Block 1(SIB 1)). The relationship (mapping) between the PDCCH monitoring opportunity and the SSB index may be determined based on § 13 of 3GPP TS 38.213. The PDCCH monitoring opportunity may also be referred to as a PDCCH monitoring period or the like.

When the ID of the search space for OSI or paging is not 0 and the UE is in IDLE/INACTIVE mode (IDLE/INACTIVE mode), the UE may determine a PDCCH monitoring opportunity to monitor for OSI or paging based on the relationship between the actually transmitted ssb (actual transmitted ssb) and the PDCCH monitoring opportunity (e.g., § 7.1 of 3GPP TS 38.304, § 5 of TS 38.331, etc.).

Fig. 1 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for OSI and SSB in Rel-15 NR.

The System Information (SI) window length corresponds to the length of a window (period) that can be used for scheduling of the SI, and for example, 5 time slots, 10 time slots, … …, 1280 time slots, and the like may be set in the UE by higher layer signaling.

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

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), RMSI, OSI, or the like.

The System Information (SI) period corresponds to a period of an SI message in a radio frame unit, and may be set to the UE by higher layer signaling, for example, 8 radio frames, 16 radio frames, … …, 512 radio frames, and the like.

The UE may be set with a higher layer parameter regarding a transmission unit of a plurality of aggregated SSBs (for example, may be referred to as a Radio Resource Control (RRC) parameter "SSB-positioninglnburst"). The transmission unit of the SSB may also be referred to as a transmission period of the SSB, an SSB set, an SS burst set, an SSB burst, or simply a burst. An SS burst may also mean a set of SSBs included every certain period (e.g., half frame (0.5 radio frame)). The higher layer parameter may also be referred to as information (parameter) related to the location of the time domain of the transmitted SSB within the SS burst. In the present disclosure, the higher layer parameter is described as ssb-positioninglnburst, but the name is not limited thereto.

The ssb-positioninglnburst may also differ in size (bit length) depending on the frequency utilized by the serving cell. ssb-positioninburst may be defined as, for example, 4 bits for frequencies of 3GHz or 2.4GHz or less, 8 bits for frequencies of 3GHz or from 2.4GHz to 6GHz, and other 64 bits. In other words, the size of SSB-positioninburst may be 4 or 8 bits in case of SSB SubCarrier Spacing (SCS) of 15kHz or 30kHz, and may be larger than 8 bits in case of SSB SubCarrier Spacing of 120kHz or 240 kHz. Of course, the frequency, SCS, size of ssb-PositionsInBurst, etc. are not limited thereto.

SSB-positioninglnburst is a bitmap with the leftmost (first) bit corresponding to SSB index #0, the 2 nd bit corresponding to SSB index #1, … …, and so on, each bit representing an SSB transmission candidate location within an SS burst. A value of '1' of the bit indicates that the corresponding SSB is transmitted, and '0' indicates that the corresponding SSB is not transmitted.

In the present disclosure, the SSB transmission candidate position may indicate a position of a first symbol of the SSB candidate. The SSB index may also indicate the location of the SSB for each particular period (e.g., half frame (0.5 radio frame)).

The SSB index may be expressed by a maximum number of 3 bits in a Frequency Range 1(FR1)), or may be acquired by the UE through a sequence of DMRS of PBCH. The SSB index may be represented by the lower 3 bits of the PBCH-based DMRS sequence, the upper 3 bits of the PBCH-based payload, and the total number of 6 bits in Frequency Range 2(FR2), or may be acquired by the UE based on these.

The UE may also assume a QCL between SSBs corresponding to the same SSB index of the same cell. Further, the UE may not assume that the SSBs corresponding to different SSB indexes of the same cell are QCL.

Fig. 1 shows PDCCH monitoring opportunities 1 st, 2 nd, … … nth, N +1 st, … … within an SI window. The UE may assume that the PDCCH monitoring opportunity at X × N + K times (here, X is 0, 1, … …, X-1, and K is 1, 2, … …, N) corresponds to the SSB actually transmitted at the K time.

X may be the smallest integer equal to or larger than the value obtained by dividing the number of monitoring opportunities in the SI window by N. N may correspond to the number of SSBs actually transmitted (for example, 8 or less if SSB-positioninsburst is 8 bits) determined by SSB-positioninsburst.

The UE may also assume the same Quasi-Co-location (qcl) for PDCCH monitoring opportunities associated with the same SSB. For example, in the 1 st and N +1 st PDCCH monitoring opportunities of fig. 1, the UE assumes the same QCL as the 1 st transmitted SSB to receive the PDCCH. The same shaded PDCCH monitoring opportunities of fig. 1 may also indicate that the same beam is applied (or QCL with the same SSB is envisaged). The differently shaded PDCCH monitoring opportunities of fig. 1 may also represent the application of respectively different beams (or consider QCLs with respectively different SSBs) to them.

The QCL may be an index indicating statistical properties of at least one of a signal and a channel (expressed as a signal/channel). For example, when a certain signal/channel and another signal/channel have a QCL relationship, at least 1 of doppler shift (doppler shift), doppler spread (doppler spread), average delay (average delay), delay spread (delay spread), and Spatial Parameter (Spatial Parameter) (for example, Spatial Rx Parameter) may be assumed to be the same (QCL is defined as at least 1 of them) among these different signals/channels.

A UE is assumed to be in a specific QCL (e.g., QCL type D) relationship with another COntrol REsource SET (countrol REsource SET: CORESET), channel or reference signal, and may also be referred to as QCL assumption.

Fig. 2 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for paging and SSB in Rel-15 NR.

The starting position of PDCCH monitoring for the Paging Frame (PF) and the Downlink Control Information for paging (Downlink Control Information (DCI)) may be determined based on the ID of the UE. The PF may be defined by 1 or more radio frames.

The UE may also be set with higher layer parameters (e.g., also referred to as RRC parameters "first pdcch-monitoring occasionofpo") related to the initial Paging Opportunity (PO) in the PF. In the present disclosure, the higher layer parameter is described as firstdcch-MonitoringOccasionOfPO, but the name is not limited thereto.

When the firstdcch-monitoring occasionofpo is set, the UE may assume that a period of S PDCCH monitoring opportunities from a PDCH monitoring opportunity designated by the firstdcch-monitoring occasionofpo corresponds to PO. The UE may perform PDCCH monitoring for paging at a PDCCH monitoring opportunity (timing of a shaded block in fig. 2) included in the PO. The unshaded block in fig. 2 may correspond to a PDCCH monitoring opportunity not used for paging, among PDCCH monitoring opportunities.

Fig. 2 shows PDCCH monitoring opportunities at 1 st, 2 nd, … … st, S th within a PO. The UE may also assume that the kth PDCCH monitoring opportunity in the PO corresponds to the kth SSB that is actually transmitted. Here, S may correspond to the number of SSBs actually transmitted (for example, 8 or less if SSB-positioninsburst is 8 bits) determined by SSB-positioninsburst. The different shading of fig. 2 may also indicate that different respective beams are applied (or QCLs for different SSBs are envisaged).

In addition, when the ID of the search space used for OSI or paging is not 0 and the UE is in a CONNECTED mode (CONNECTED mode), the UE may monitor all the set PDCCH monitoring opportunities based on the search space setting set by the higher layer signaling. That is, in this case, the UE does not particularly assume the relationship between the monitoring opportunity of PDCCH for monitoring and the SSB index.

< SSB of NR-U >

In NR-U, the use of SSB is also being investigated. Further, signals including Channel State Information (CSI) -Reference signals (Reference Signal (RS)), SSB burst sets (sets of SSBs), and CORESET and PDSCH associated with SSBs within 1 continuous burst Signal are being studied. This Signal may be referred to as a Discovery Reference Signal (DRS, NR-U DRS, or the like), a Discovery Reference Signal, a Discovery Signal (DS), or the like.

The CORESET (pdcch) associated with the SSB may be referred to as Remaining Minimum System Information (RMSI) -CORESET, CORESET #0, or the like. The RMSI may also be referred to as SIB 1. The PDSCH associated with the SSB may be a PDSCH carrying RMSI (RMSI PDSCH), or a PDSCH scheduled by a PDCCH (DCI having a Cyclic Redundancy Check (CRC)) scrambled by System Information (SI) -Radio Network Temporary Identifier (RNTI)) in RMSI-CORESET.

SSBs with different SSB indices may also be transmitted using different beams (base station transmit beams). The SSB and its corresponding RMSI PDCCH and RMSI PDSCH may also be transmitted using the same beam.

Regarding NR-U, considering a case where SSB cannot transmit due to failure of LBT, a transmission candidate location of an extended SSB is being studied. For example, research is underway: in a certain period (DRS transmission window) during which DRS may be transmitted, SSB transmission candidate positions are extended, and SSBs (beams) that have failed to transmit due to LBT failure are transmitted using other transmission candidate positions within the window.

The length of the DRS transmission window may be set in the UE by higher layer signaling, or may be defined by a specification. The DRS transmission window may also be referred to as a DRS transmission period, a DRS transmission window period, and the like.

Fig. 3A and 3B are diagrams showing an example of extension of the SSB transmission candidate position. In this example, consider the SCS of the serving cell (or SSB) to be 30kHz and the slot length to be 0.5 ms. Further, it is assumed that the length of the DRS transmission window is 5 ms. The same SCS and DRS transmission window lengths are also assumed in the following figures. In addition, the application of the present disclosure is not limited to these SCS, DRS transmission window lengths.

In fig. 3A, DRSs are transmitted over 4 slots (slots #0- # 3). Here, in the slot #0 of fig. 3A, the SSB, the CORESET (pdcch) associated with the SSB, and the PDSCH (portion other than the SSB and the CORESET) associated with the SSB are shown. Other time slots may be similarly configured. In fig. 3A, SSB # i (i ═ 0 to 7) and RMSI # i (PDCCH/PDSCH) may be transmitted using the same beam.

Fig. 3B shows a case where slots #0- #1 of fig. 3A cannot be transmitted due to LBT busy (LBT failure). In this case, the UE may also assume that: the beams of the SSBs #0 to #3 that are not transmitted are transmitted in the time slots subsequent to the SSBs #4 to #7 by the SSBs #8 to #11, respectively.

That is, in this example, PDCCH monitoring opportunities for RMSI are associated with SSB indexes respectively corresponding to SSB candidate positions within the DRS window.

Fig. 4 is a diagram showing another example of extension of the SSB transmission candidate position. In this example, the number of transmission SSBs is 8, and the number of transmission SSBs is the same as the number of beams (the number of beams is also 8 (beam indexes #0 to # 7)). In this case, the beam index # k corresponds to the SSB index #8i + k (i ═ 0, 1, 2).

As described above, in Rel-15 NR, the actually transmitted SSB index is notified by the RRC parameter SSB-positioninburst. However, in the NR-U, as shown in fig. 3B and 4, the SSB may be transmitted at a position (different SSB index) different from the SSB candidate position that the UE is semi-statically set by SSB-positioninglnburst. And the SSB index actually transmitted may be changed per DRS transmission period.

Further, in NR-U, in order to support independent operation, reception of OSI, paging, and the like with NR-U carriers is being studied. As shown in fig. 1 and 2, in Rel-15 NR, when used in the idle/inactive mode except for search space 0, a PDCCH monitoring opportunity is determined based on a relationship with an SSB index that is actually transmitted. However, even when the extended SSB candidate position is actually transmitted due to LBT failure, the UE determines the position of the transmitted SSB index by SSB-positioninburst. The relation between the extended SSB index and the PDCCH monitoring period, which cannot be expressed by SSB-positioninburst, is not clear.

In addition, in the Frequency Range 1(FR1)) of NR studied so far, 4 or 8 SSBs can be used at the maximum, but a case where the number of SSBs actually transmitted is smaller than that is considered. For example, as shown in fig. 4, assuming that the QCL is assumed to have a transmission SSB number of 8, when the number of actually transmitted SSBs is less than 8, the available candidate positions (candidate resources, candidate SSB indexes) of the SSBs are limited.

Further, although the SSBs of the NR studied so far are allocated 2 at most per slot, it is also conceivable to use only 1 SSB per slot for flexible control. If the processing of the SSB candidate index that is not used is not clearly defined (for example, it is also conceivable that which SSB index is QCL is associated with), the operation of the base station, UE, and the like becomes unclear.

These problems will be described with reference to fig. 5A and 5B. Fig. 5A and 5B are diagrams illustrating an example of problems assumed by the QCL of the SSB.

Fig. 5A corresponds to a case where the number of SSBs (the number of beams) is less than 8. In this example, SSB-PositionsInBurst denotes SSB indices #0- #3, and beam indices #0- #3 correspond to SSB indices #0- # 3.

In this example, slots #0- #2 are not transmitted due to a failure of LBT. It is problematic in which SSB transmission candidate position the beam indexes #0 to #3 corresponding to the SSB indexes #0 to #3 to be transmitted in the slots #0 and #1 are transmitted. If a fixed relationship corresponding to the SSB number 8 as shown in fig. 4 is used, the beam indices #0- #3 correspond to the SSB indices #8- #11, but the SSB indices #4- #7 become unusable. There is a need to define QCL assumptions that can use idle candidate SSB indices without waste.

Fig. 5B corresponds to a case where the number of SSBs (number of beams) per slot is 1. In this example, SSB-positioninburst indicates SSB indices #0, #2, #4, and #6, and SSB indices #0, #2, #4, and #6 are respectively corresponded by beam indices #0- # 3.

In this example, slots #0- #2 are not transmitted due to a failure of LBT. It is problematic in which SSB transmission candidate position the beam indexes #0 to #2 corresponding to the SSB indexes #0, #2, and #4 that should be transmitted in the slots #0 to #2 are transmitted. It is conceivable that the beam indexes #0 to #2 are transmitted using the SSB indexes #7 to #9 immediately after the SSB index #6, or the beam indexes #0 to #2 are transmitted using the SSB indexes #8, #10, and #12 so that the number of SSBs per slot is maintained to be 1. In the specifications studied so far, it is not possible to determine which.

Thus, in the case where the SSB transmitted semi-statically is notified using SSB-positioninburst, research has not been advanced as far as the UE appropriately judges QCL assumption between SSB indexes in consideration of LBT failure. Also, when SSB-positioningburst cannot be used, no research has been made regarding the assumption that the UE appropriately determines QCL between SSB indexes in consideration of LBT failure. If these are not clearly defined, the PDCCH cannot be appropriately monitored, and the communication throughput may be lowered.

Therefore, the inventors of the present invention thought: assuming that the QCL between the SSB indexes (SSB transmission candidate positions) in the NR-U carriers is clarified, even when the SSB index (position) transmitted from a specific beam changes according to the LBT result, a method of operating using the SSB can be appropriately realized.

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

In addition, in the present disclosure, SSBs corresponding to SSB indexes are also referred to as SSB indexes only. The beam corresponding to the beam index is also referred to as only the beam index.

The beam index may correspond to a set of SSB indices that can be assumed by the QCL within the DRS transmission window. Therefore, the beam index may also be replaced with an effective SSB index (effective SSB index). On the other hand, the SSB index indicating only the SSB candidate position within the DRS transmission window may be replaced with an SSB position index, a position index (location index), or the like.

Further, the NR-U of the present disclosure is not limited to the LAA, and may also include a case where an unlicensed band is independently used.

(Wireless communication method)

< embodiment 1 >

In an embodiment, the QCL assumption between SSB indices in NR-U carriers may also be determined by specification and higher layer signaling. For example, the UE may also be conceived as: each SSB index up to a slot including an SSB corresponding to the largest SSB index indicated by a specific higher layer parameter (for example, SSB-positioninburst) and SSBs corresponding to SSB indexes of slots subsequent to the slot are QCL in this order.

Fig. 6 is a diagram showing an example of QCL assumption between SSB indexes in one embodiment. In this example, SSB-PositionsInBurst indicates SSB indexes #0- #3, that is, a case where the maximum SSB index indicated by SSB-PositionsInBurst is 3 is shown.

In this case, SSB indices #0- #3 correspond to beam indices #0- # 3. The UE may also assume that the SSB indices #4i- #4i +3(i is a natural number) and the SSB indices #0- #3 are QCLs, respectively. That is, in this example, the largest SSB index represented by SSB-positioninburst corresponds to the last SSB in a certain slot, and thus the repetition of the beam is divided by slots, which is convenient for control.

In this example, slots #0- #2 are not transmitted due to a failure of LBT. The beam indexes #0 to #3 corresponding to the SSB indexes #0 to #3 that should be transmitted in the slots #0 and #1 may be transmitted in the slots #3 and #4(SSB indexes #6 to #9) within the same DRS transmission window.

The UE may also assume that SSB indices #6, #7, #8, and #9 and SSB indices #2, #3, #0, and #1 are QCLs, respectively. That is, the UE may also assume that the SSB indices #6, #7, #8, and #9 are transmitted using the beam indices #2, #3, #0, and #1, respectively.

Fig. 7 is a diagram showing another example of QCL assumption between SSB indexes in one embodiment. In this example, SSB-PositionsInBurst indicates SSB indexes #0- #4, that is, a case where the largest SSB index indicated by SSB-PositionsInBurst is 4 is shown.

In this case, SSB indices #0- #4 correspond to beam indices #0- # 4. The UE assumes that SSB index #5 included in the same slot as SSB index #4, which is the largest SSB index indicated by SSB-positioninburst, is invalid (Not Available/Not Applicable (NA)), and may Not count the number of SSBs actually transmitted.

The UE may also assume that the SSB indices #6i- #6i +4(i is a natural number) and the SSB indices #0- #4 are QCLs, respectively. The UE may assume that SSB index #6i +5 is NA as with SSB index # 5. That is, in this example, the maximum SSB index indicated by SSB-positioninburst can divide the repetition of beams by slots even if the SSB index is not the last SSB in a certain slot, and control is facilitated.

In this example, slots #0- #2 are not transmitted due to a failure of LBT. The beam indexes #0- #4 corresponding to the SSB indexes #0- #4 that should be transmitted in the slots #0- #2 may be transmitted in the slots #3- #5(SSB indexes #6- #10) within the same DRS transmission window.

The UE may also assume that the SSB indices #6, #7, #8, #9, and #10 and the SSB indices #0, #1, #2, #3, and #4 are QCLs, respectively. That is, the UE may also assume that the SSB indices #6, #7, #8, #9, and #10 are transmitted using the beam indices #0, #1, #2, #3, and #4, respectively.

Fig. 8 is a diagram showing another example of QCL assumption between SSB indexes in one embodiment. In this example, SSB-positioninburst indicates SSB indices #1, #3, #5, and #7, that is, a case where the maximum SSB index indicated by SSB-positioninburst is 7 is shown.

In this case, the SSB indices #1, #3, #5, and #7 are respectively corresponding to the beam indices #0, #1, #2, and # 3. The UE assumes that, among the indexes up to SSB index #7, which is the largest SSB index represented by SSB-positioninglnburst, closed (OFF) (corresponding to '0') SSB indexes #0, #2, #4, and #6 are invalid (NA), and may not count as the number of actually transmitted SSBs.

The UE may also assume that the SSB indices #8i +1, #8i +3, #8i +5, and #8i +7 and the SSB indices #1, #3, #5, and #7 are QCLs, respectively. The UE may assume that the SSB indices #8i, #8i +2, #8i +4, and #8i +6 are NA as with the SSB indices #0, #2, #4, and # 6. That is, in this example, it is possible to prevent an arbitrary SSB index and an SSB index of NA from being regarded as a QCL.

In this example, slots #0- #2 are not transmitted due to a failure of LBT. SSB index #7 of slot #3 is transmitted with beam index # 3. The beam indexes #0, #1, and #2 corresponding to the SSB indexes #1, #3, and #5 that should be transmitted in the slots #0 to #2 may be transmitted in the slots #4 to #6(SSB indexes #9, #11, and #13) within the same DRS transmission window.

The UE may also assume that the SSB indices #9, #11, and #13 and the SSB indices #1, #3, and #5 are QCLs, respectively. That is, the UE may also assume that the SSB indices #7, #9, #11, and #13 are transmitted using the beam indices #3, #0, #1, and #2, respectively.

In addition, in an embodiment, the UE may also assume that: each SSB index up to a specific period (for example, at least 1 out of a subframe, a half slot, a symbol, and the like) in which an SSB corresponding to the largest SSB index indicated by SSB-positioninglnburst is included, and SSBs corresponding to SSB indexes after the specific period are QCL in this order.

In one embodiment, the SSB transmission candidate positions in the NR-U carriers may be located in all slots within a specific period (for example, a half frame 5ms long). The SSB transmission candidate position may be defined over the specific period (for example, up to 6 ms).

For example, when the period of the DRS transmission window can be set in the UE by higher layer signaling, SSB transmission candidate positions and SSB indexes are defined for all slots in the set period of the DRS transmission window.

Here, the SSB transmission candidate positions within the slot may be based on the SCS using at least 1 of cases A, B, C, D and E specified in TS38.213 § 4.1Cell search of 3GPP Rel-15, or other candidate positions may be used.

Further, cases a and C may correspond to a case where 2 SSBs within 1 slot are not contiguous (separated) in the time domain. Case A can also be used for 15kHz SCS. Case C can also be used for 30kHz SCS. Case B may also be equivalent to the case where 2 SSBs within 1 slot are consecutive in the time domain. Case B may also be used for 30kHz SCS.

In addition, the utilized situation (for example, at least one of the situations B and C) may be specified by the specification with respect to the 30kHz SCS, or may be notified by using higher layer signaling, physical layer signaling, or a combination thereof.

The partial SSB transmission candidate location may also be set to invalid. For example, as shown in fig. 7 and 8, it is also conceivable that, in SSB-positioninglnburst, the skipped SSB index (i.e., the SSB index corresponding to the bit corresponding to '0' and the subsequent bit appearing to be '1') and the SSB index which is the QCL are not valid. Furthermore, it is also conceivable that: in SSB-positioninglnburst, the SSB index corresponding to the bit of the slot corresponding to '0' and the same as the maximum SSB index and the SSB index, which is QCL, are not valid.

In an embodiment, in the monitoring operation of the paging PDCCH in the NR-U carrier, the PO may also include the same number of PDCCH monitoring opportunities as the number of all valid SSB transmission candidate locations. That is, with reference to fig. 2, the number S of PDCCH monitoring opportunities in the PO may be replaced by the number of valid SSB transmission candidate positions.

Here, the valid SSB transmission candidate positions may be SSB indexes indicated to be transmitted by SSB-positioninburst and SSB indexes assumed to be QCL with the SSB indexes included in the DRS transmission window.

That is, the number of valid SSB transmission candidate positions may be the number obtained by adding the number of SSB indexes indicated to be transmitted by SSB-positioninglnburst and the number of SSB indexes assumed to be QCL to the SSB indexes included in the DRS transmission window.

The description will be given by taking fig. 7 as an example. In the case of fig. 7, the SSB indices indicated as being transmitted by SSB-positioninginburst are 5 of SSB indices #0- # 4. Also, QCL for SSB indexes #0 to #4 in the DRS transmission window are 12 of SSB indexes #6 to #10, #12 to #16, and #18 to # 19. Therefore, the number of valid SSB transmission candidate positions (valid SSB indexes) is 17.

Fig. 9 is a diagram showing an example of a relationship between a PDCCH monitoring opportunity for paging and an SSB in one embodiment. While S PDCCH monitoring opportunities correspond to different beams in fig. 2, S PDCCH monitoring opportunities include PDCCH monitoring opportunities (assumed by the same QCL) corresponding to the same beam in fig. 9, and are different from each other.

According to the above-described embodiment, the QCL assumption between SSB indexes can be appropriately determined.

< embodiment 2 >

The above ssb-positioninburst is notified to the UE using SIB1 or RRC signaling. Therefore, in the case where SSB-positioninglnburst cannot be used (for example, at the time of initial access), it is difficult to assume QCL concerning different SSB candidate positions in the above-described method.

In addition, when 8 or more are supported as the number of SSB candidate positions (or in a cell in which 8 or more are used), it is being studied that the UE acquires an index specific to the SSB candidate position as an SSB index by a combination of DMRS (or DMRS sequence) and the payload of PBCH.

In the NR specifications studied so far, when the UE reports the Power or quality of the peripheral cells (for example, Synchronization Signal Reference Signal Received Power (SS-RSRP)) during Radio Resource Management (RRM) measurement, the SSB index of each peripheral cell may need to be acquired. Considering UE load, measurement delay, etc., it is preferable to avoid decoding the PBCH payload of each neighboring cell in order to acquire the SSB index.

The inventors of the present invention have focused on that the RRM measurement report on the peripheral cell is actually important for the beam index of the SSB of the peripheral cell (effective SSB index). In an embodiment, the UE derives the effective SSB index based on the sequence of the DMRS of the PBCH. For example, the sequence of the DMRS of the PBCH may also be generated based on the effective SSB index. Thus, since the effective SSB index can be determined based on only the DMRS, the UE may omit the decoding of the PBCH.

In other words, the UE may perform at least one of cell identification and RRM measurement by acquiring an effective SSB index without acquiring an SSB index for the detected specific cell and the neighboring cells having the same frequency as the specific cell.

When the UE performs a measurement report of power or quality of the neighboring cell in the RRM measurement, the effective SSB index (beam index) may be used as the SSB index.

The maximum number of effective SSB indices may also be a particular number (e.g., 8). That is, the maximum value of the effective SSB index may be a value obtained by subtracting 1 from the specific number (for example, 8-1 — 7). The maximum number of effective SSB indices may be determined by the specification, or may be notified through higher layer signaling or the like.

The UE may also be conceived as: the same effective SSB index may be utilized in different SSB candidate locations (location indices) within the DRS transmission window.

Further, the inventors of the present invention have conceived that the UE includes information for deriving the frame timing (or half frame timing) in the PBCH payload, and transmits the common PBCH payload by traversing the SSBs within the burst. By making the PBCH payloads of different SSBs in an SS burst common in the unlicensed frequency, soft combining of PBCH in bursts is easily achieved, and degradation of detection characteristics of PBCH, degradation of detection delay, and the like can be prevented.

The payload of the PBCH transmitted within the DRS transmission window may also include at least 1 of the following (1) and (2):

(1) information on how many SSB candidate positions (position indexes) the same effective SSB index repeats (or offset information from the start position of the SSB burst to the position index at which SSB index 0 is transmitted is executed);

(2) information of SSB candidate position index where transmission of SSB burst is started.

The UE may derive the frame timing based on the effective SSB index obtained from the sequence of the DMRS in the PBCH and at least one of the information (1) and the information (2). In addition, conventionally used field index information may be used for deriving the frame timing.

The information of the above (1) may also be referred to as information on the number of transmitted effective SSB indexes, information on the maximum value of the effective SSB indexes, information on the period of the effective SSB indexes, information on the unit of wrap around (or wrap around), information on the unit of repeated transmission of SSBs, information on the length of SSB bursts, and the like. The wrap-around may mean that 0 is returned after the index reaches the maximum value, such as the effective SSB index.

The information of the above (2) may also be referred to as, for example, a burst start SSB candidate position index, a burst start position index, or the like.

Based on the number of transmission effective SSB indexes, the UE determines (judges) a position index corresponding to an effective SSB index within the DRS transmission window for the detected cell and a neighboring cell of the same frequency (at least a cell of the same operator).

The UE determines (judges) the half frame timing of the detected cell and the neighboring cell of the same frequency based on the burst start position index. In the present disclosure, field timing, frame timing, slot timing, and the like may be replaced with each other.

The number of the transmission effective SSB indexes and the burst start position index are the same within 1 DRS transmission window. Therefore, the UE may be notified of the information contained in the MIB in the payload of the PBCH, or may be notified of the information other than the MIB in the payload of the PBCH.

By configuring each piece of information in this way, in a PBCH Transmission period (PBCH Transmission Time Interval (PBCH TTI)), since the content of PBCHs becomes the same, the UE can synthesize and receive each PBCH in the PBCH Transmission period, and can improve reception quality. The PBCH TTI may be, for example, 40ms or 80 ms.

The information on the number of transmission effective SSB indices is not limited to PBCH or MIB, and may be notified to the UE by using at least 1 SIB (for example, SIB1), RRC signaling, or the like.

In the case where the UE supports NR-U independence, a specific value determined by the specification may also be assumed as the number of the above-described transmission effective SSB indexes in the initial access. This is because, when the UE derives the effective SSB index (in other words, the pattern of DMRS in PBCH) across the transmission period of DRS or the transmission period of SSB by the combined reception, it is preferable to perform processing assuming that the number of transmission effective SSB indexes is a specific value.

In addition, in the present disclosure, the UE may also assume that the SSB index notified with SSB-positioninginburst means an effective SSB index.

Fig. 10A to 10C and fig. 11A to 11C are diagrams showing specific examples of the effective SSB index in one embodiment. In this example, the case of using the effective SSB indices #0 to #3 will be described. That is, the transmission effective SSB index number (the length of the SSB burst) is 4.

In fig. 10A, the base station succeeds in the first LBT within the DRS transmission window, and transmits SSBs in location indexes #0, #1, #2, and #3 using effective SSB indexes #0, #1, #2, and #3, respectively. The PBCH of the SSB includes information indicating that the burst start position index is #0 and information indicating that the transmission effective SSB index number is 4 (or the offset from the start position to the effective SSB index #0 is 0).

In fig. 10B, in the location index #0, the SSB is not transmitted due to the failure of LBT. The base station transmits SSBs at position indexes #1, #2, #3, and #4 using effective SSB indexes #1, #2, #3, and #0, respectively. The PBCH of the SSB includes information indicating burst start position index #1 and information indicating transmission effective SSB index number 4 (or offset from the start position to effective SSB index #0) 3.

In fig. 10C, in the location indexes #0 and #1, the SSB is not transmitted due to the failure of LBT. The base station transmits SSBs at position indexes #2, #3, #4, and #5 using effective SSB indexes #2, #3, #0, and #1, respectively. The PBCH of the SSB includes information indicating burst start position index #2 and information indicating transmission effective SSB index number 4 (or offset from the start position to effective SSB index #0) 2.

In fig. 11A, SSB is not transmitted due to failure of LBT in position indexes #0- # 2. The base station transmits SSBs in position indices #3, #4, #5, and #6 using effective SSB indices #3, #0, #1, and #2, respectively. The PBCH of the SSB includes information indicating burst start position index #3 and information indicating transmission effective SSB index number 4 (or offset from the start position to effective SSB index #0) 1.

In fig. 11B, in the position indexes #0 to #3, SSB is not transmitted due to failure of LBT. The base station transmits SSBs at position indexes #4, #5, #6, and #7 using effective SSB indexes #0, #1, #2, and #3, respectively. The PBCH of the SSB includes information indicating burst start position index #4 and information indicating transmission effective SSB index number of 4 (or offset from the start position to effective SSB index #0) of 0.

In fig. 11C, SSB is not transmitted due to failure of LBT in position indexes #0- # 13. The base station transmits SSBs at position indexes #14, #15, #16, and #17 using effective SSB indexes #2, #3, #0, and #1, respectively. The PBCH of the SSB includes information indicating burst start position index #14 and information indicating transmission effective SSB index number 4 (or offset from the start position to effective SSB index #0) 2.

When detecting the SSB, the UE decodes the PBCH, and grasps the burst start position index and the number of transmission effective SSB indexes (or the offset). The UE may derive the effective SSB index based on the number of effective SSB indices to be transmitted (or the offset) and the sequence of the DMRS for the PBCH included in the SSB.

In these examples, since the number of transmission effective SSB indexes is 4, the UE may assume that the effective SSB indexes #0, #1, #2, and #3 correspond to the position indexes #4i (i ═ 0, 1, … …), #4i +1, #4i +2, and #4i + 3. The UE may apply the same QCL assumption to SSBs of different location indexes corresponding to the same effective SSB index.

In addition, the UE may also determine a location index of the detected SSB based on the effective SSB index and the burst start location index. Next, the UE may derive the frame timing based on the position index of the SSB.

For example, if the effective SSB index #3 is obtained from the DMRS sequence of the received PBCH of the SSB and the burst start position index indicated by the decoded PBCH is #14, the UE can assume that an SSB burst as shown in fig. 11C is transmitted. When the effective SSB index #3 is acquired and the burst start position index indicated by the decoded PBCH is #1, the UE can assume that an SSB burst as shown in fig. 10B is transmitted.

In embodiment 2, even when the base station continuously repeats transmission of the same beam a plurality of times within an SSB burst, it is necessary to make the effective SSB indexes of the SSBs within the SSB burst different as #0, #1, #2, and … …. This is because if the same effective SSB index exists within the SSB burst, frame timing cannot be determined. Therefore, even SSBs of different effective SSB indices may utilize the same beam (i.e., be QCL).

Therefore, the information on the QCL relationship between different effective SSB indices may also be notified to the UE using higher layer signaling (e.g., SIB, RRC signaling, etc.), physical layer signaling (e.g., DCI), or a combination of these. Based on this information, it may be determined whether the UE can apply the same QCL assumption or different QCL assumptions for different effective SSB indexes. According to such a configuration, even when the base station repeatedly transmits the same beam, the UE side can grasp the situation and can perform averaging or the like based on measurement results of a plurality of SSBs of the same beam in the SSB burst.

According to the above-described embodiment, the QCL assumption between SSB indexes can be appropriately determined. Further, the UE can derive the frame timing appropriately based on the PBCH of the SSB.

(Wireless communication System)

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

Fig. 12 is a diagram showing an example of a schematic configuration of a radio communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) standardized by the Third Generation Partnership Project (3GPP), New wireless (5th Generation mobile communication system New Radio (5G NR)) of the fifth Generation mobile communication system, or the like.

In addition, the wireless communication system 1 may also support Dual Connectivity (Multi-RAT Dual Connectivity (MR-DC)) between a plurality of Radio Access Technologies (RATs). The MR-DC may include Dual Connectivity of LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC))), Dual Connectivity 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 (gNB) of NR is MN, and the base station (eNB) of LTE (E-UTRA) is SN.

The wireless communication system 1 may support Dual connection between a plurality of base stations in the same RAT (for example, Dual connection between MN and 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 a base station 12(12a to 12C) arranged within the macrocell C1 and forming a small cell C2 narrower than the macrocell C1. The user terminal 20 may also be located in at least one cell. The arrangement, number, and the like of each cell and user terminal 20 are not limited to the illustrated embodiments. Hereinafter, the base stations 11 and 12 are collectively referred to as the base station 10 without distinguishing them.

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

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

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

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

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

The user terminal 20 may be a terminal supporting at least one of communication 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) may be used. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used 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 radio 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, as the Downlink Channel, a Downlink Shared Channel (Physical Downlink Shared Channel (PDSCH))), a Broadcast Channel (Physical Broadcast Channel (PBCH))), a Downlink Control Channel (Physical Downlink Control Channel (PDCCH))) and the like that are Shared by the user terminals 20 may be used.

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

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

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

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

For PDCCH detection, a COntrol REsource SET (countrol REsource SET (CORESET)) and a search space (search space) may also be utilized. CORESET corresponds to the resource that searches for DCI. The search space corresponds to a search region and a search method of PDCCH candidates (PDCCH candidates). A CORESET may also be associated with one or more search spaces. The UE may also monitor the CORESET associated with a search space based on the search space settings.

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

Uplink Control Information (UCI) including at least 1 of Channel State Information (CSI), transmission acknowledgement Information (for example, HARQ-ACK, ACK/NACK, and the like, which may also be referred to as Hybrid Automatic Repeat reQuest (HARQ-ACK), and Scheduling ReQuest (SR)) may also be transmitted through the PUCCH. Through the PRACH, a random access preamble for connection establishment with the cell may also be transmitted.

In the present disclosure, downlink, uplink, and the like may be expressed without being given "link". Note that the beginning of each channel may be expressed without giving "Physical (Physical)" thereto.

In the wireless communication system 1, a Synchronization Signal (SS), a Downlink Reference Signal (DL-RS), and the like may be transmitted. In the wireless communication system 1, 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 DL-RSs.

The Synchronization Signal may be at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS), for example. The signal blocks containing SS (PSS, SSs) and PBCH (and DMRS for PBCH) may also be referred to as SS/PBCH blocks, SS blocks (blocks) (SSB), 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 (Sounding Reference Signal (SRS)), a demodulation Reference Signal (DMRS), and the like may be transmitted as an Uplink Reference Signal (UL-RS). In addition, the DMRS may also be referred to as a user terminal specific Reference Signal (UE-specific Reference Signal).

(base station)

Fig. 13 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 transmission/reception unit 120, a transmission/reception antenna 130, and a transmission line interface (transmission line interface) 140. The control unit 110, the transmission/reception unit 120, the transmission/reception antenna 130, and the transmission line interface 140 may be provided in one or more numbers.

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

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

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

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

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

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

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

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

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

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 (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-analog conversion on a bit sequence to be transmitted, and output a baseband signal.

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

On the other hand, the transmission/reception section 120(RF section 122) performs amplification, filtering, demodulation of a baseband signal, and the like on a signal of a radio frequency band received by the transmission/reception antenna 130.

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

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

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

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

Further, transmitting/receiving section 120 may transmit information (for example, a high-level parameter "SSB-positioninburst") regarding the position of a Synchronization Signal Block (SSB) within a Synchronization Signal (SS) burst to user terminal 20.

Transmitting/receiving section 120 may also transmit SSBs, DRSs, and the like.

(user terminal)

Fig. 14 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. Further, the control unit 210, the transmission/reception unit 220, and the transmission/reception antenna 230 may be provided with one or more antennas.

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

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

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

The transceiver unit 220 may also include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband section 221 may include a transmission processing section 2211 and a reception processing section 2212. The 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 of the present disclosure.

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

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

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

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

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

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

Whether or not DFT processing is applied may be set based on transform precoding (transform precoding). When the conversion 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, or may not perform DFT processing as the transmission processing otherwise.

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

On the other hand, the transmission/reception section 220(RF section 222) may amplify, filter, demodulate a baseband signal, or the like, with respect to 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 (including error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the obtained baseband signal to obtain user data.

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

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, transmission/reception section 220 may receive information (for example, a high-level parameter "SSB-positioninburst") regarding the position of a Synchronization Signal Block (SSB) within a burst of a Synchronization Signal (SS). This Information may be notified by at least one of System Information Block 1(SIB1) and RRC signaling, for example.

Control section 210 may also determine, based on information on the location of the SSB within the SS burst, a Quasi-Co-location (qcl) assumption between SSB indices within a transmission window of a Discovery Reference Signal (DRS) in a carrier (e.g., an unlicensed carrier) to which monitoring is applied.

The carrier to which the listening is applied may also be referred to as an LAA cell, an LAA secondary cell (LAA SCell), or the like. In the carrier where the listening is applied, the user terminal 20 may also listen before transmitting. Here, the "listening" of the present disclosure may also be replaced by at least 1 of Listen Before Talk (LBT)), Clear Channel Assessment (CCA)), carrier sensing, sensing of a Channel, Channel access operation, and the like.

The control unit 210 may assume that the SSBs corresponding to the SSBs up to the slot including the SSB corresponding to the largest SSB index notified by the information on the position of the SSB in the SS burst and the SSBs corresponding to the SSB indexes of the slots subsequent to the slot are QCL in this order.

Control section 210 may assume that the QCL of the SSB index is repeatedly used in a period unit from the starting time slot of SSB-positioninglnburst to the time slot including the SSB corresponding to the largest SSB index within the RS transmission window. For example, control section 210 may assume that the QCL of the period unit is reapplied from the next slot including the slot of the SSB corresponding to the largest SSB index.

In the time slot including the SSB corresponding to the largest SSB index, control section 210 may regard the SSB index larger than the largest SSB index as invalid (may not count the number of SSBs actually transmitted).

It is also conceivable that Control section 210 monitors the number of opportunities for a Physical Downlink Control Channel (PDCCH) for paging included in a pager in a carrier to which the monitoring is applied, and determines the number of transmitted SSB indexes of 1 or more based on the sum of the number of SSB indexes notified by information on the position of the SSB in the SS burst and the number of SSB indexes having QCLs as the SSB indexes of 1 or more.

Control section 210 may determine QCL estimates for the PDCCH and the SSB in a PDCCH monitoring opportunity for receiving at least one of Other System Information (OSI)) and paging (paging) based on various QCL estimates, and monitor (or receive) the PDCCH. In addition, OSI, paging, etc. may also be replaced by other information (e.g., a specific DCI format).

The transceiver unit 220 may also receive (or detect) SSBs. Control section 210 may acquire an effective SSB index based on the DMRS of the PBCH included in the SSB. In this case, control section 210 may omit acquisition of an SSB index for the SSB, or may omit (or not perform) decoding of the PBCH, for example.

Control section 210 may acquire, from the payload of the PBCH, at least one of information on the number of transmitted effective SSB indexes and a start position index of an SSB burst including the SSB within a DRS transmission window.

Control unit 210 may also apply soft combining to the decoding of a plurality of the PBCH within the SSB burst. The transceiver unit 220 may also synthesize and receive the PBCH within the SSB burst.

(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 and/or indirectly (for example, by wire, wireless, or the like) connecting two or more apparatuses physically or logically separated. The functional blocks may also be implemented by software in combination with the above-described 1 device or the above-described devices.

Here, the functions include judgment, determination, judgment, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, establishment, comparison, assumption, expectation, view, broadcast (broadcasting), notification (notification), communication (communicating), forwarding (forwarding), configuration (setting), reconfiguration (resetting), allocation (allocating, mapping), assignment (assigning), and the like, but are not limited to these. For example, a function block (a configuration unit) that functions transmission may be referred to as a transmitting unit (transmitting unit), a transmitter (transmitter), or the like. As described above, the method of implementation 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. 15 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment. The base station 10 and the user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In addition, in the present disclosure, words such as a device, a circuit, an apparatus, a section (section), and a unit can be mutually replaced. 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 specific 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 transmission/reception 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 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 constituted by at least 1 of Read Only Memory (ROM), erasable Programmable ROM (erasable Programmable ROM) (EPROM), Electrically EPROM (EEPROM), Random Access Memory (RAM), 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 1 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, or another suitable storage medium, for example. 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 transmission/reception section 120(220), the transmission/reception section 130(230), and the like may be realized by the communication apparatus 1004. The transmitting and receiving unit 120(220) may also be physically or logically separated by the transmitting unit 120a (220a) and the receiving unit 120b (220 b).

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a 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, a Light Emitting Diode (LED) 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 constituted by 1 bus or by buses different among devices.

The base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), and a Field Programmable Gate Array (FPGA), and some or all of the functional blocks may be implemented by the hardware. For example, the processor 1001 may be implemented with at least 1 of these hardware.

(modification example)

In addition, terms described in the present disclosure and/or 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. Each of the 1 or more periods (frames) constituting the radio frame may also be referred to as a subframe. Further, the subframe may be formed of 1 or more slots in the time domain. The subframe may be a fixed length of time (e.g., 1ms) independent of a parameter set (numerology).

Here, the parameter set may also refer to 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 1 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 in the time domain (Orthogonal Frequency Division Multiplexing (OFDM) symbol, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, or the like). Further, the time slot may be a time unit based on the parameter set.

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 also be made up of fewer symbols than the number of slots. 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 with 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 of frames, subframes, slots, mini-slots, symbols, etc. in the present disclosure may be substituted for each other.

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. Note that the unit indicating TTI may be referred to as a slot (slot), a mini-slot (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, the time interval (e.g., the number of symbols) to which a transport block, code block, codeword, etc. is actually mapped may be shorter than the TTI.

In addition, in a case where 1 slot or 1 mini-slot is referred to as a TTI, 1 or more TTIs (i.e., 1 or more slots or 1 or more mini-slots) 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 the 1ms time length may also be referred to as a normal TTI (TTI in 3GPP Rel.8-12), a normal (normal) TTI, a long (long) TTI, a normal subframe, a normal (normal) subframe, a long (long) subframe, a slot, and the like. 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 a plurality of consecutive subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the parameter set, and may be 12, for example. The number of subcarriers included in the RB may also be decided based on the parameter set.

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

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 be referred to as a partial Bandwidth) may indicate a subset of consecutive common RBs (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 by a certain BWP, and may also be numbered within the BWP.

The BWP may include UL BWP (BWP for UL) and DL BWP (BWP for DL). It is also possible to set 1 or more BWPs for the UE within 1 carrier.

At least 1 of the provisioned BWPs may also be active, and the UE may not also assume to transmit or receive a specific signal/channel outside the active BWP. In addition, "cell", "carrier", and the like in the present disclosure may also be replaced with "BWP".

The structure of the radio frame, the subframe, the slot, the mini slot, the symbol, and the like is merely an example. For example, 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 other configurations may be variously changed.

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 also be indicated by a specific index.

The names used for parameters and the like in the present disclosure are not limitative names in any point. Further, the numerical 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, information, signals, and the like may be output to at least one of: from a higher layer (upper layer) to a lower layer (lower layer), and 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, etc. that are input and output may also 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 Information in the present disclosure may be implemented by physical layer signaling (e.g., Downlink Control Information (DCI)), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast Information (Master Information Block (MIB)), System Information Block (SIB)), etc.), Medium Access Control (MAC) signaling, other signals, or a combination thereof.

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

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

The determination may be 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 also mean a device (e.g., a base station) included in the network.

In the present disclosure, terms of "precoding", "precoder", "weight (precoding weight)", "Quasi-Co-location (qcl))", "Transmission setting Indication state (Transmission Configuration Indication state) (TCI 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 are used interchangeably.

In the present disclosure, terms such as "Base Station (BS)", "wireless Base Station", "fixed Station (fixed Station)", "NodeB", "enb (enodeb)", "gnb (gtnodeb)", "access Point (access Point)", "Transmission Point (TP)", "Reception Point (RP)", "Transmission Reception Point (TRP)", "panel" "cell", "sector", "cell group", "carrier", "component carrier" are 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., 3) 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 a communication service through a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))), "cell" or "sector", or other terms, refer to a part or all of the coverage area of at least one of the base station and the base station subsystem that performs a communication service in the coverage area.

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

A mobile station is also sometimes referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, 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 a mobile body, the mobile body itself, or the like. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving body (e.g., an unmanned aerial vehicle, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station 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 Internet of Things (IoT) device such as a sensor.

Further, the base station in the present disclosure may be replaced by a user terminal. For example, the embodiments and implementation 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, may also be referred to as Device-to-Device (D2D)), Vehicle networking (V2X), and the like). In this case, the user terminal 20 may have the function of the base station 10. Also, words such as "upstream", "downstream", etc. may be replaced with words corresponding to inter-terminal communication (e.g., "side"). For example, the uplink channel, the downlink channel, and the like may be replaced with the side channel.

Likewise, the user terminal in the present disclosure may also be replaced with a base station. In this case, the base station 10 may have 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 apparent 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), and the like are 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 shown in 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 Long Term Evolution (LTE), LTE-Advanced (LTE-a), LTE-Beyond (LTE-B), SUPER3G, IMT-Advanced, 4th generation Mobile communication System (4th generation communication System (4G)), 5th generation Mobile communication System (5G)), Future Radio Access (FRA)), Radio Access Technology (New-RAT), New Radio (NR)), New Radio Access (NX)), next generation Radio Access (FX), Global Mobile communication System (Global System for Mobile communication (GSM) and Mobile Broadband (CDMA) registration (2000) B)), and so on, IEEE 802.11(Wi-Fi (registered trademark)), IEEE 802.16(WiMAX (registered trademark)), IEEE 802.20, Ultra-wideband (uwb), Bluetooth (registered trademark)), a system using another appropriate wireless communication method, a next generation system expanded based on them, and the like. Further, a plurality of systems may be applied in combination (for example, combination of LTE or LTE-a and 5G).

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. elements in this disclosure is not intended to limit the number or order of such elements in a comprehensive manner. 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 specification may include 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.

The term "determination (decision)" may be used to refer to "determination (decision)" of reception (e.g., reception information), transmission (e.g., transmission information), input (input), output (output), access (e.g., access to data in a memory), and the like.

The "determination (decision)" may be regarded as "determination (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 "determination (decision)" may be replaced with "assumption", "expectation", "assumption".

The terms "connected", "coupled" and the like, or all variations thereof, used in the present disclosure mean all connections or couplings, direct or indirect, 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 "access".

In the present disclosure, when 2 or more elements are connected, it can be considered that 1 or more wires, cables, printed electrical connections, and the like are used, and as some non-limiting and non-exhaustive examples, electromagnetic energy having a wavelength in a radio frequency domain, a microwave domain, a light (both visible light and invisible light) domain, and the like are used to be "connected" or "coupled" to each other.

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

Where the terms "including", "comprising" and variations thereof are used in this disclosure, these terms are meant 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 such as a, an, and the in english are added by translation, the present disclosure includes cases where nouns after these articles are 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. Accordingly, the description of the present disclosure is intended to be illustrative, and not to be construed as limiting the invention in any way.