WO2020054074A1

WO2020054074A1 - User terminal and wireless communication method

Info

Publication number: WO2020054074A1
Application number: PCT/JP2018/034286
Authority: WO
Inventors: 一樹武田; 聡永田; リフェワン; ギョウリンコウ
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2018-09-14
Filing date: 2018-09-14
Publication date: 2020-03-19

Abstract

A user terminal according to one embodiment is characterized by including: a receiving unit that receives a reference signal (BFD-RS: Beam Failure Detection Reference Signal) for beam failure detection; and a control unit that, if more than a prescribed number of COntrol REsource SETs (CORESETs) are set and a set of reference signal indices corresponding to resources for the BFD-RS are not set by upper level layer signaling, determines reference signal indices up to the prescribed number to be included in the set, on the basis of a Transmission Configuration Indication (TCI) state set for each CORESET.

Description

User terminal and wireless communication method

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

In a UMTS (Universal Mobile Telecommunications System) network, long term evolution (LTE: Long Term Evolution) has been specified for the purpose of higher data rates and lower delays (Non-Patent Document 1). LTE-A (LTE Advanced, LTE @ Rel. 10-14) has been specified for the purpose of further increasing the capacity and sophistication of LTE (LTE @ Rel. 8, 9).

Succession system of LTE (for example, FRA (Future Radio Access), 5G (5th generation mobile communication system), 5G + (plus), NR (New Radio), NX (New radio access), FX (Future generation radio access), LTE Rel. 14 or 15 or later) are also being studied.

In the existing LTE system (LTE Rel. 8-14), monitoring of radio link quality (radio link monitoring (RLM: Radio Link Monitoring)) is performed. When a radio link failure (RLF: Radio @ Link @ Failure) is detected from the RLM, re-establishment of an RRC (Radio @ Resource @ Control) connection is requested to a user terminal (UE: User @ Equipment).

In a future wireless communication system (for example, NR), a procedure for detecting a beam failure and switching to another beam (may be referred to as a beam failure recovery (BFR) procedure, BFR, etc.) may be performed. Is being considered.

For BFR, the UE detects a beam impairment using the configured reference signal resources. On the other hand, in the current NR, when the resource is not set, the UE corresponds to a transmission setting instruction (TCI: Transmission Configuration Indication) state (TCI-state) of a control resource set (CORESET: Control REsource SET). It has been studied to use up to two reference signal indices as a set of indices corresponding to the resource.

Therefore, if the resource is not set for the UE and more than two coresets are set, the UE will select two cores to be included in the set from more than two indices corresponding to these coresets. You need to determine the index up to.

However, how to select the indexes to be included in the set in such a case has not been studied. If this is not clearly defined, the beam failure cannot be detected properly, and the communication throughput may be reduced.

Therefore, an object of the present disclosure is to provide a user terminal and a wireless communication method that can appropriately detect a beam failure.

A user terminal according to an aspect of the present disclosure includes a receiving unit that receives a reference signal (BFD-RS: Beam Failure Detection Reference Signal) for detecting a beam failure, and a plurality of RESETs (CONtrol REsource SET) that are more than a predetermined number. If the set of reference signal indices corresponding to the set BFD-RS resources is not set by higher layer signaling, the set is included in the set based on the TCI (Transmission Configuration Indication) state set in each RESET. A control unit for determining up to a predetermined number of reference signal indices.

According to one aspect of the present disclosure, a beam failure can be appropriately detected.

FIG. 1 is a diagram showing an example of a beam recovery procedure in Rel-15 NR. FIG. 2 is a diagram illustrating an example of determining an RS index according to an embodiment. FIG. 3 is a diagram illustrating another example of the determination of the RS index according to the embodiment. FIG. 4 is a diagram illustrating another example of the determination of the RS index according to the embodiment. FIG. 5 is a diagram illustrating an example of a schematic configuration of the wireless communication system according to the embodiment. FIG. 6 is a diagram illustrating an example of the overall configuration of the base station according to the embodiment. FIG. 7 is a diagram illustrating an example of a functional configuration of the base station according to the embodiment. FIG. 8 is a diagram illustrating an example of the overall configuration of the user terminal according to the embodiment. FIG. 9 is a diagram illustrating an example of a functional configuration of the user terminal according to the embodiment. FIG. 10 is a diagram illustrating an example of a hardware configuration of a base station and a user terminal according to an embodiment.

In NR, it is being studied to perform communication using beamforming. For example, the UE and the base station may use a beam used for signal transmission (also referred to as a transmission beam, a Tx beam, or the like), a beam used for signal reception (also referred to as a reception beam, an Rx beam, or the like), or the like.

In NR, when the quality of a specific beam deteriorates in order to suppress the occurrence of a radio link failure (RLF: Radio @ Link @ Failure), switching to another beam (beam recovery (BR: Beam @ Recovery), beam failure Implementation of a recovery (BFR: Beam \ Failure \ Recovery), L1 / L2 (Layer \ 1 / Layer \ 2) beam recovery procedure may be considered. Note that the BFR procedure may be simply called BFR.

Note that a beam failure in the present disclosure may be referred to as a link failure.

FIG. 1 is a diagram showing an example of a beam recovery procedure in Rel-15 NR. The number of beams and the like are merely examples, and are not limited thereto. In the initial state (step S101) of FIG. 1, the UE performs measurement based on a reference signal (RS) resource transmitted using two beams.

The RS may be at least one of a synchronization signal block (SSB: Synchronization Signal Block) and a channel state measurement RS (CSI-RS: Channel State Information RS). The SSB may be called an SS / PBCH (Physical Broadcast Channel) block or the like.

RS is a primary synchronization signal (PSS: Primary @ SS), a secondary synchronization signal (SSS: Secondary @ SS), a mobility reference signal (MRS: Mobility @ RS), a signal included in SSB, SSB, CSI-RS, and a demodulation reference signal ( At least one of DMRS (DeModulation Reference Signal), a beam-specific signal, or the like, or a signal configured by extending or changing these may be used. The RS measured in step S101 may be called an RS for beam failure detection (BFD-RS: Beam Failure Detection RS) or the like.

ＵＥ In step S102, the UE cannot detect the BFD-RS (or the reception quality of the RS deteriorates) due to the interference of the radio wave from the base station. Such interference may occur, for example, due to the effects of obstacles, fading, interference, etc. between the UE and the base station.

The UE detects a beam failure when a predetermined condition is satisfied. For example, when the BLER (Block @ Error @ Rate) is less than the threshold value for all the set BFD-RSs, the UE may detect the occurrence of the beam failure. When occurrence of a beam failure is detected, a lower layer (physical (PHY) layer) of the UE may notify (instruct) a beam failure instance to an upper layer (MAC layer).

The criterion (criterion) for determination is not limited to BLER, but may be reference signal reception power (L1-RSRP: Layer 1 Reference Signal 物理 Received Power) in the physical layer. Note that RSRP of the present disclosure may be replaced with RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), and other information related to power or quality.

{Also, beam failure detection may be performed based on a downlink control channel (PDCCH) instead of or in addition to the RS measurement. The BFD-RS may be expected to be the DMRS and Quasi-Co-Location (QCL) of the PDCCH monitored by the UE.

ＱHere, the QCL is an index indicating the statistical property of the channel. For example, if one signal / channel and another signal / channel are in a QCL relationship, doppler shift (doppler shift), doppler spread (doppler spread), average delay (average delay) between these different signals / channels. ), Delay spread (delay @ spread), and spatial parameter (Spatial @ parameter) (e.g., spatial reception parameter (Spatial @ Rx @ Parameter)) means that it can be assumed that they are the same (QCL for at least one of these). May be.

Note that the spatial reception parameter may correspond to a reception beam (for example, a reception analog beam) of the UE, and the beam may be specified based on the spatial QCL. QCL (or at least one element of QCL) in the present disclosure may be read as sQCL (spatialpatQCL).

Information on BFD-RS (for example, RS index, resource, number, number of ports, precoding, etc.), information on beam impairment detection (BFD) (for example, the above-described threshold), etc., are transmitted to the UE using upper layer signaling. (Notification). The information on the BFD-RS may be replaced with the information on the resource for the BFD, the information on the BFD-RS resource, and the like.

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

The MAC signaling may use, for example, a MAC control element (MAC CE (Control Element)), a MAC PDU (Protocol Data Unit), or the like. The broadcast information includes, for example, a master information block (MIB: Master Information Block), a system information block (SIB: System Information Block), minimum system information (RMSI: Remaining Minimum System Information), and other system information (OSI: Other). System @ Information).

The MAC layer of the UE may start a predetermined timer (which may be called a beam failure detection timer) when receiving the beam failure instance notification from the PHY layer of the UE. When the MAC layer of the UE receives the beam failure instance notification a certain number of times (eg, beamFailureInstanceMaxCount set by RRC) before the timer expires, it triggers the BFR (eg, starts one of random access procedures described later). ).

The base station may determine that the UE has detected a beam failure when there is no notification from the UE or when a predetermined signal (a beam recovery request in step S104) is received from the UE.

In step S103, the UE starts searching for a new candidate beam (new @ candidate @ beam) to be newly used for communication for beam recovery. The UE may select a new candidate beam corresponding to the predetermined RS by measuring the RS. The RS measured in step S103 may be called an RS (NCBI-RS: New Candidate Beam Identification RS) for identifying a new candidate beam, a CBI-RS, a CB-RS (Candidate Beam RS), or the like. The NCBI-RS may be the same as or different from the BFD-RS. Note that the new candidate beam may be simply referred to as a candidate beam.

The UE may determine a beam corresponding to an RS satisfying a predetermined condition as a new candidate beam. The UE may determine a new candidate beam based on, for example, an RS whose L1-RSRP exceeds a threshold value among the set NCBI-RSs. The criterion (criterion) for determination is not limited to L1-RSRP. L1-RSRP for SSB may be referred to as SS-RSRP. L1-RSRP for CSI-RS may be referred to as CSI-RSRP.

Information on the NCBI-RS (eg, RS resources, number, number of ports, precoding, etc.), information on the new candidate beam identification (NCBI) (eg, the above-described threshold), etc., are transmitted to the UE using higher layer signaling or the like. It may be set (notified). The information on the NCBI-RS may be obtained based on the information on the BFD-RS. Information on the NCBI-RS may be referred to as information on an NBCI resource or the like.

Note that the BFD-RS, the NCBI-RS, and the like may be replaced with a radio link monitoring reference signal (RLM-RS: Radio Link Monitoring RS).

In step S104, the UE that has identified the new candidate beam transmits a beam recovery request (BFRQ: Beam \ Failure \ Recovery \ reQuest). The beam recovery request may be called a beam recovery request signal, a beam failure recovery request signal, or the like.

BFRQ includes, for example, an uplink control channel (PUCCH: Physical Uplink Control Channel), a random access channel (PRACH: Physical Random Access Channel), an uplink shared channel (PUSCH: Physical Uplink Shared Channel), and a configured grant (PUSCH) PUSCH. May be transmitted using at least one of the following.

BFRQ may include information on the new candidate beam specified in step S103. Resources for BFRQ may be associated with the new candidate beam. The beam information includes a beam index (BI: Beam @ Index), a port index of a predetermined reference signal, a resource index (for example, a CSI-RS resource index (CRI: CSI-RS @ Resource @ Indicator), an SSB resource index (SSBRI)), and the like. The notification may be made by using.

With Rel-15 @ NR, CB-BFR (Contention-Based @ BFR) which is a BFR based on a collision random access (RA) procedure and CF-BFR (Contention-Free) which is a BFR based on a non-collision random access procedure. BFR) is being considered. In CB-BFR and CF-BFR, the UE may transmit a preamble (also referred to as a RA preamble, a random access channel (PRACH: Physical {Random} Access Channel), a RACH preamble, or the like) as a BFRQ using PRACH resources.

In CB-BFR, the UE may transmit a preamble randomly selected from one or more preambles. On the other hand, in CF-BFR, the UE may transmit a preamble assigned from the base station to the UE. In CB-BFR, the base station may assign the same preamble to multiple UEs. In CF-BFR, the base station may assign a preamble to each UE.

Note that CB-BFR and CF-BFR are called CB PRACH-based BFR (CBRA-BFR: contention-basedCHPRACH-based BFR) and CF PRACH-based BFR (CFRA-BFR: contention-free PRACH-based BFR), respectively. You may. CBRA-BFR may be called CBRA for BFR. CFRA-BFR may be referred to as CFRA for BFR.

Regardless of CB-BFR or CF-BFR, information on PRACH resources (RA preamble) may be notified by, for example, higher layer signaling (RRC signaling). For example, the information may include information indicating a correspondence between the detected DL-RS (beam) and the PRACH resource, and a different PRACH resource may be associated with each DL-RS.

In step S105, the base station that has detected the BFRQ transmits a response signal to the BFRQ from the UE (may be called a gNB response or the like). The response signal may include reconfiguration information on one or a plurality of beams (for example, configuration information of a DL-RS resource).

The response signal may be transmitted in, for example, a UE common search space of the PDCCH. The response signal is reported using a PDCCH (DCI) scrambled by a cyclic redundancy check (CRC: Cyclic Redundancy Check) by an identifier of the UE (for example, Cell-Radio RNTI (C-RNTI)). Is also good. The UE may determine at least one of a transmit beam and a receive beam to use based on the beam reconfiguration information.

The UE may monitor the response signal based on at least one of a BFR control resource set (CORESET: Control REsource SET) and a BFR search space set.

Regarding the CB-BFR, when the UE receives the PDCCH corresponding to the C-RNTI for itself, it may be determined that the contention resolution is successful.

Regarding the process of step S105, a period for the UE to monitor a response (response) to the BFRQ from the base station (for example, gNB) may be set. The period may be called, for example, a gNB response window, a gNB window, a beam recovery request response window, or the like. The UE may retransmit BFRQ if there is no gNB response detected within the window period.

In step S106, the UE may transmit a message indicating that the beam reconfiguration has been completed to the base station. The message may be transmitted by, for example, the PUCCH or may be transmitted by the PUSCH.

Beam recovery success (BR success) may represent, for example, a case where the process reaches step S106. On the other hand, the beam recovery failure (BR @ failure) may correspond to, for example, reaching a predetermined number of BFRQ transmissions or expiring a beam failure recovery timer (Beam-failure-recovery-Timer).

Note that the numbers of these steps are merely numbers for explanation, and a plurality of steps may be put together or the order may be changed. Whether to perform BFR may be set in the UE using higher layer signaling.

By the way, in NR, it is considered that the base station sets up to two BFD resources per BWP (Bandwidth Part) for the UE using upper layer signaling. For example, the UE may be provided with resources related to the purpose of the beam failure (“beamFailure”) in the resource setting information for failure detection (eg, “failureDetectionResourcesToAddModList”, “failureDetectionResources”, etc. of the upper layer parameters). .

The UE may be provided with a set of indices corresponding to the resources for BFD according to the higher layer parameters. The set may be, for example, a set of indexes of periodic CSI-RS resource settings (for example, non-zero power CSI-RS resource ID). The set is the set q ₀ bar (here, q ₀ bar notation given the overline to "q _0") may be referred to as index set. Hereinafter, this set is simply referred to as “set q ₀ ”.

The UE may perform L1-RSRP measurement or the like using the RS resource corresponding to the index included in the set q ₀ to detect a beam failure.

On the other hand, in the current NR, if the UE does not provide the above-described upper layer parameter indicating the information of the index corresponding to the resource for BFD, the transmission setting instruction (TCI: CORESET) used for monitoring the PDCCH is provided. studied to determine the index of Transmission Configuration indication) state (TCI-state) the same value as the RS index in RS set indicated by the periodic CSI-RS resource configuration, to include in the set q ₀ Have been.

The TCI state is determined, for example, between a target channel (or a reference signal (RS: Reference Signal) for the channel) and another signal (for example, another downlink reference signal (DL-RS: Downlink Reference Signal)). It may be information on QCL. Here, the information element of the TCI state (“TCI-state @ IE” of RRC) set by higher layer signaling may include one or more pieces of QCL information (“QCL-Info”).

The QCL information may include at least one of information on a DL-RS having a QCL relationship (DL-RS related information) and information indicating a QCL type (QCL type information). The DL-RS related information may include information such as a DL-RS index (eg, SSB index, non-zero power CSI-RS resource ID), a cell index where the RS is located, a BWP index where the RS is located, and the like.

The parameters (or parameter sets) that can be assumed to be the same differ depending on the QCL type, and the following four QCL types AD may be provided. The parameters are as follows:
QCL type A: Doppler shift, Doppler spread, average delay and delay spread,
・ QCL type B: Doppler shift and Doppler spread,
QCL type C: average delay and Doppler shift,
QCL type D: spatial reception parameters.

The UE expects the set q ₀ to contain up to two RS indexes. Note that when one TCI state has two RS indexes, it is considered that the set q ₀ includes an RS index corresponding to the setting of QCL type D for the corresponding TCI state.

With NR, more than two (eg, three) CORESETs can be set per BWP for the UE. In addition, one or more TCI states indicating the QCL relationship between the DMRS port of the PDCCH and a predetermined DL-RS (CSI-RS, SSB, etc.) may or may not be set for CORRESET.

Therefore, if more than two coresets are set for the UE and the upper layer parameter indicating the information of the index corresponding to the resource for BFD is not provided, the UE sets two coresets corresponding to these coresets. from greater RS indexes, it is necessary to determine the index of up to 2 to include in the set q _0.

However, about how to select the index to be included in the set q ₀ How did such a case, studies have not progressed. If this is not clearly defined, the beam failure cannot be detected properly, and the communication throughput may be reduced.

Therefore, the present inventors have conceived a method of determining a reference signal index for appropriately detecting a beam disturbance.

Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. The wireless communication method according to each embodiment may be applied alone or in combination.

In the following description, a case will be described as an example where the UE is not provided with the upper layer parameter indicating the information of the index corresponding to the BFD resource, but the present invention is not limited to this. The following embodiments, a predetermined number to be included in the set q ₀ (e.g., 2) is applicable to any case of determining the index up.

(Wireless communication method)
In one embodiment, a predetermined number (e.g., two) greater than CORESET is when it is set to UE, from TCI condition being set for these CORESET, to determine the index until the predetermined number to be included in the set _{q 0} Regarding the rules for. Hereinafter, the description will be given assuming that the predetermined number is two.

The UE includes a TCI state in which only one or two of the coresets to be set have up to two RS indices (eg, a coreset other than the one or two coresets does not have a TCI state set) , Or TCI states with more than two RS indexes), the set q ₀ may include up to the two RS indexes of the one or two CORRESET.

FIG. 2 is a diagram illustrating an example of determination of an RS index according to an embodiment. In this example, a part of information elements (IE: Information @ Element) and parameters included in the RRC signaling set in the UE are shown.

The RRC information element related to DL BWP (for example, “BWP-DownlinkDedicated IE”) may include an RRC information element related to PDCCH setting (for example, “PDCCH-Config IE”). The RRC information element related to the PDCCH setting may include one or more RRC information elements related to the RESET setting (for example, “ControlResourceSet @ IE”) (three in the figure). Each CORSET @ ID (for example, RRC parameter “ControlResourceSetId”) is # 1, # 2, and # 3, respectively.

FIG. 2 shows the TCI state specified (activated) by MAC @ CE among the TCI states set in CORRESET. Here, the UE may determine the TCI state for the UE-specific PDCCH (CORESET) based on RRC signaling and MAC @ CE.

The UE may activate one or more TCI states for each CORESET using MAC $ CE. The MAC CE may be referred to as a UE-specific PDCCH TCI state indication MAC CE (TCI State Indication for UE-specific PDCCH MAC CE). The UE may monitor the CORESET based on an active TCI state corresponding to the CORESET.

In this example, the RESET settings corresponding to RESET @ ID = # 1- # 2 each include at least one RRC information element (eg, "TCI-State @ IE") related to the TCI state, and one TCI state is active. . On the other hand, the RESET setting corresponding to RESET @ ID = # 3 does not include the RRC information element related to the TCI state (is not set).

The RRC information element for the TCI state may include one or more QCL information (eg, RRC parameter “QCL-Info”). The active TCI state corresponding to CORSET @ ID = # 1 corresponds to TCI state ID (for example, RRC parameter “TCI-StateId”) = # 1 and includes QCL information indicating a QCL relationship with RS index # 1. The active TCI state corresponding to CORESET # = # 2 corresponds to TCI state ID = # 2, and includes QCL information indicating a QCL relationship with RS index # 2. That is, each of these TCI states corresponds to one RS index.

Thus, in the example of FIG. 2, UE, of the RS index associated with TCI state corresponding to the three CORESET set it may determine that include RS index # 1 and # 2 to set _{q 0.}

FIG. 3 is a diagram showing another example of the determination of the RS index according to the embodiment. In this example, some of the information elements and parameters included in the RRC signaling similar to FIG. 2 are shown.

FIG. 3 differs from FIG. 2 in that:
The RESET setting corresponding to RESET ID = # 3 includes an RRC information element related to the TCI state, and one TCI state is active;
The active TCI state corresponding to CORESET ID = # 3 corresponds to TCI state ID = # 3, and includes QCL information indicating a QCL relationship with RS indexes # 3, # 4, and # 5. This TCI state corresponds to three RS indexes.

In the example of FIG. 3, UE, of the RS index associated with TCI state corresponding to the three CORESET set it may determine that include RS index # 1 and # 2 to set _{q 0.}

Incidentally, RS index included in the set _{q 0} may be restricted to the index corresponding to the active TCI state of CORESET, it may be determined from the index corresponding to all of the TCI state set in CORESET.

If the coreset for which the TCI state is set has a total of more than two RS indices (eg, in more than two coresets, the TCI state including the respective RS index is active): (1), (2) and based on one or sequentially consisting of a combination of (3) (priority order), select CORESET up to two, the RS index included in the CORESET set _{q 0} May include:
(1) CORRESET in which one RS is set in one TCI state,
(2) Two RSs are set in one TCI state, one of which is a RESET corresponding to the relationship of QCL type D,
(3) CORESET corresponding to a (lower) CORESET ID.

The order (priority order) of selecting $ CORESET is interchangeable. That is, the priority order is (1) → (2) → (3), (1) → (3) → (2), (2) → (3) → (1), (2) → (1) → (3), (3) → (2) → (1) and (3) → (1) → (2).

Here, for example, in the order of (1) → (2) → (3), if there is no RESET corresponding to the above (1), it is determined whether there is a RESET corresponding to the above (2), and further the above (2) is determined. if there is no corresponding CORESET to), it is determined whether there is CORESET corresponding to the above (3), determines the CORESET corresponding to the set _{q 0} in the order of.

Note that the above (3) may be read as the following (3 ′):
(3 ′) CORRESET corresponding to a lower (lower) TCI state ID. Here, the TCI state ID may be, for example, an active TCI state ID, a minimum value of the set TCI state ID, or the like.

In (3) or (3 ′), “smaller” may be read as “greater”.

FIG. 4 is a diagram showing still another example of the determination of the RS index according to the embodiment. In this example, some of the information elements and parameters included in the RRC signaling similar to FIG. 3 are shown.

FIG. 4 differs from FIG. 3 in that:
The active TCI state corresponding to CORESET ID = # 2 corresponds to TCI state ID = # 2, and the first QCL information indicating the QCL relation with RS index # 2 and the QCL relation with RS index # 4 And the second QCL information indicating The second QCL information indicates QCL type D.
The active TCI state corresponding to CORESET ID = # 3 corresponds to TCI state ID = # 3, and includes QCL information indicating a QCL relationship with RS index # 3.

That is, a RESET corresponding to RESET @ ID = # 1 and # 3 corresponds to a RESET in which one RS is set in one TCI state, and a RESET corresponding to RESET @ ID = # 2 corresponds to 2 in one TCI state. One RS is set, and one of them corresponds to CORRESET corresponding to the relationship of QCL type D.

Assuming that the order of selecting the coreset is (1) → (3) → (2) described above, in the example of FIG. 4, in the TCI state corresponding to the three coresets to be set according to the above (1). among the relevant RS indexes, it may determine that include RS index # 1 and # 3 to the set _{q 0.}

According to the embodiment described above, it can be appropriately determine the index to include in the set q _0.

<Modification>
In one embodiment, if more than two coresets are set for the UE and no upper layer parameter indicating information of the index corresponding to the resource for BFD is provided, more than two coresets corresponding to these coresets are provided. from RS index, a method for determining the RS index of up to 2 to include in the set q ₀ may be dependent on the implementation of the UE.

In one embodiment, the network (eg, a base station) may control the UE to have at most two RESETs with a setting of the TCI state. In this case, even when more than two CORESET is set to UE, it can be limited to two RS indexes that are candidates for inclusion in the set _{q 0} at the maximum.

In each of the embodiments described above, the set q ₀ is determined to include up to a predetermined number (eg, two) of RS indexes over the CORESET. However, in another embodiment, the set q ₀ includes the predetermined number ( For example, it may be changed to include up to two) RS indexes. In this case, even when more than two CORESET is set to UE, it can tolerate that the number of RS indexes included in the set _{q 0} is greater than 2.

In this case, the number of BFD resources that the base station can set for the BWP for the UE may be a predetermined number (for example, two) for the RESET. For example, the number of BFD resources that can be set for BWP (for example, corresponding to the size of “failureDetectionResourcesToAddModList” of the upper layer parameter) may be 6.

Note that each embodiment of the present disclosure may be applied when more than two coresets are not set for the UE. For example, to determine up to two RS indexes to be included in set q ₀ from more than two RS indexes corresponding to these TCI states, such as when more than two TCI states are active for a given CORESET, Embodiments of the present disclosure may be applied.

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

FIG. 5 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. In the wireless communication system 1, at least one of carrier aggregation (CA) and dual connectivity (DC) in which a plurality of basic frequency blocks (component carriers) each having a system bandwidth (for example, 20 MHz) as one unit is applied. Can be.

The wireless communication system 1 includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), and 5G. (5th generation mobile communication system), NR (New Radio), FRA (Future Radio Access), New-RAT (Radio Access Technology), etc., or a system for realizing these.

The wireless communication system 1 may support dual connectivity between a plurality of RATs (Radio Access Technology) (multi-RAT dual connectivity (MR-DC: Multi-RAT Dual Connectivity)). The MR-DC has dual connectivity (LTE and NR) in which an LTE (E-UTRA) base station (eNB) becomes a master node (MN) and an NR base station (gNB) becomes a secondary node (SN). EN-DC: E-UTRA-NR {Dual} Connectivity, NR base station (gNB) becomes MN, and LTE (E-UTRA) base station (eNB) becomes SN. Dual connectivity (NR and LTE) NE-DC: NR-E-UTRA {Dual} Connectivity) may be included.

The wireless communication system 1 has dual connectivity between a plurality of base stations in the same RAT (for example, dual connectivity in which both the MN and the SN are NR base stations (gNB) (NN-DC: NR-NR @ Dual @ Connectivity)). ) May be supported.

The wireless communication system 1 includes a base station 11 forming a macro cell C1 having relatively wide coverage, and a base station 12 (12a to 12c) arranged in the macro cell C1 and forming a small cell C2 smaller than the macro cell C1. Have. Further, user terminals 20 are arranged in the macro cell C1 and each small cell C2. The arrangement, number, and the like of each cell and the user terminals 20 are not limited to the modes shown in the figure.

The user terminal 20 can be connected to both the base station 11 and the base station 12. It is assumed that the user terminal 20 uses the macro cell C1 and the small cell C2 simultaneously using CA or DC. Further, the user terminal 20 may apply CA or DC using a plurality of cells (CC).

Communication between the user terminal 20 and the base station 11 can be performed using a carrier having a relatively low frequency band (for example, 2 GHz) and a narrow bandwidth (also referred to as an existing carrier or a legacy carrier). On the other hand, between the user terminal 20 and the base station 12, a carrier having a relatively high frequency band (for example, 3.5 GHz, 5 GHz, or the like) and a wide bandwidth may be used, or between the user terminal 20 and the base station 11. The same carrier as described above may be used. Note that the configuration of the frequency band used by each base station is not limited to this.

The user terminal 20 can perform communication in each cell by using at least one of time division duplex (TDD: Time Division Duplex) and frequency division duplex (FDD: Frequency Division Duplex). In each cell (carrier), a single numerology may be applied, or a plurality of different numerologies may be applied.

The base station 11 and the base station 12 (or between the two base stations 12) may be connected by wire (for example, an optical fiber or an X2 interface compliant with CPRI (Common Public Radio Interface)) or wirelessly. Good.

The base station 11 and each base station 12 are respectively connected to the upper station apparatus 30, and are connected to the core network 40 via the upper station apparatus 30. Note that the higher station apparatus 30 includes, for example, an access gateway apparatus, a radio network controller (RNC), a mobility management entity (MME), and the like, but is not limited thereto. Further, each base station 12 may be connected to the higher station apparatus 30 via the base station 11.

Note that the base station 11 is a base station having relatively wide coverage, and may be called a macro base station, an aggregation node, an eNB (eNodeB), a transmission / reception point, or the like. The base station 12 is a base station having local coverage, such as a small base station, a micro base station, a pico base station, a femto base station, a HeNB (Home eNodeB), an RRH (Remote Radio Head), a transmission / reception point, and the like. May be called. Hereinafter, when the base stations 11 and 12 are not distinguished, they are collectively referred to as a base station 10.

Each user terminal 20 is a terminal corresponding to various communication systems such as LTE, LTE-A, and 5G, and may include not only mobile communication terminals (mobile stations) but also fixed communication terminals (fixed stations).

In the wireless communication system 1, Orthogonal Frequency Division Multiple Access (OFDMA) is applied to the downlink as a wireless access method, and Single Carrier-Frequency Division Multiple Access (SC-FDMA: Single Carrier) is applied to the uplink. At least one of Frequency Division MultipleＯAccess) and OFDMA is applied.

OFDMA is a multicarrier transmission scheme in which a frequency band is divided into a plurality of narrow frequency bands (subcarriers), and data is mapped to each subcarrier for communication. SC-FDMA divides a system bandwidth into bands each composed of one or a continuous resource block for each terminal, and a single carrier transmission that reduces interference between terminals by using different bands for a plurality of terminals. It is a method. The uplink and downlink radio access schemes are not limited to these combinations, and other radio access schemes may be used.

In the wireless communication system 1, a downlink shared channel (PDSCH: Physical Downlink Shared Channel), a broadcast channel (PBCH: Physical Broadcast Channel), a downlink control channel, and the like are used as downlink channels. The PDSCH transmits user data, upper layer control information, SIB (System @ Information @ Block), and the like. Also, MIB (Master \ Information \ Block) is transmitted by PBCH.

The downlink control channel includes PDCCH (Physical Downlink Control Channel), EPDCCH (Enhanced Physical Downlink Control Channel), PCFICH (Physical Control Format Indicator Channel), PHICH (Physical Hybrid-ARQ Indicator Channel) and the like. Downlink control information (DCI: Downlink Control Information) including scheduling information of at least one of the PDSCH and the PUSCH is transmitted by the PDCCH.

Note that the DCI that schedules DL data reception may be called a DL assignment, and the DCI that schedules UL data transmission may be called an UL grant.

PCFICH may transmit the number of OFDM symbols used for the PDCCH. The PHICH may transmit HARQ (Hybrid Automatic Repeat Repeat reQuest) acknowledgment information (for example, retransmission control information, HARQ-ACK, ACK / NACK, etc.) for the PUSCH. The EPDCCH is frequency-division multiplexed with a PDSCH (Downlink Shared Data Channel) and used for transmission of DCI and the like like the PDCCH.

In the wireless communication system 1, as an uplink channel, an uplink shared channel (PUSCH: Physical Uplink Shared Channel), an uplink control channel (PUCCH: Physical Uplink Control Channel), and a random access channel (PRACH: Physical Random Access Channel) or the like is used. By PUSCH, user data, higher layer control information, etc. are transmitted. In addition, downlink radio quality information (CQI: Channel Quality Indicator), delivery confirmation information, scheduling request (SR: Scheduling Request), and the like are transmitted by PUCCH. The PRACH transmits a random access preamble for establishing a connection with a cell.

In the wireless communication system 1, as a downlink reference signal, a cell-specific reference signal (CRS: Cell-specific Reference Signal), a channel state information reference signal (CSI-RS: Channel State Information-Reference Signal), and a demodulation reference signal (DMRS: DeModulation Reference Signal, a position determination reference signal (PRS: Positioning Reference Signal), and the like are transmitted. In the wireless communication system 1, a reference signal for measurement (SRS: Sounding Reference Signal), a reference signal for demodulation (DMRS), and the like are transmitted as uplink reference signals. The DMRS may be called a user terminal specific reference signal (UE-specific Reference Signal). Further, the transmitted reference signal is not limited to these.

(base station)
FIG. 6 is a diagram illustrating an example of the overall configuration of the base station according to the embodiment. The base station 10 includes a plurality of transmitting / receiving antennas 101, an amplifier unit 102, a transmitting / receiving unit 103, a baseband signal processing unit 104, a call processing unit 105, and a transmission path interface 106. Note that the transmitting / receiving antenna 101, the amplifier unit 102, and the transmitting / receiving unit 103 may be configured to include at least one each.

ユーザ User data transmitted from the base station 10 to the user terminal 20 via the downlink is input from the higher station apparatus 30 to the baseband signal processing unit 104 via the transmission path interface 106.

In the baseband signal processing unit 104, regarding user data, processing of a PDCP (Packet Data Convergence Protocol) layer, division / combination of user data, transmission processing of an RLC layer such as RLC (Radio Link Control) retransmission control, and MAC (Medium Access) Control) Transmission / reception control (for example, HARQ transmission processing), scheduling, transmission format selection, channel coding, inverse fast Fourier transform (IFFT) processing, precoding processing, etc., and transmission / reception processing are performed. 103. The downlink control signal is also subjected to transmission processing such as channel coding and inverse fast Fourier transform, and is transferred to the transmission / reception unit 103.

(4) The transmission / reception unit 103 converts the baseband signal precoded and output from the baseband signal processing unit 104 for each antenna into a radio frequency band, and transmits the radio frequency band. The radio frequency signal frequency-converted by the transmitting / receiving section 103 is amplified by the amplifier section 102 and transmitted from the transmitting / receiving antenna 101. The transmission / reception unit 103 can be configured by a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device described based on common recognition in the technical field according to the present disclosure. Note that the transmission / reception unit 103 may be configured as an integrated transmission / reception unit, or may be configured from a transmission unit and a reception unit.

On the other hand, as for an uplink signal, a radio frequency signal received by the transmission / reception antenna 101 is amplified by the amplifier unit 102. The transmitting / receiving section 103 receives the upstream signal amplified by the amplifier section 102. Transmitting / receiving section 103 frequency-converts the received signal into a baseband signal and outputs the baseband signal to baseband signal processing section 104.

The baseband signal processing unit 104 performs fast Fourier transform (FFT: Fast Fourier Transform), inverse discrete Fourier transform (IDFT), and error correction on user data included in the input uplink signal. Decoding, reception processing of MAC retransmission control, reception processing of the RLC layer and PDCP layer are performed, and the data is transferred to the upper station apparatus 30 via the transmission path interface 106. The call processing unit 105 performs call processing (setting, release, etc.) of a communication channel, state management of the base station 10, management of radio resources, and the like.

(4) The transmission path interface 106 transmits and receives signals to and from the higher-level station device 30 via a predetermined interface. The transmission line interface 106 transmits and receives signals (backhaul signaling) to and from another base station 10 via an interface between base stations (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), an X2 interface). Is also good.

FIG. 7 is a diagram illustrating an example of a functional configuration of the base station according to the embodiment. In this example, functional blocks of characteristic portions in the present embodiment are mainly shown, and it may be assumed that base station 10 also has other functional blocks necessary for wireless communication.

The baseband signal processing unit 104 includes at least a control unit (scheduler) 301, a transmission signal generation unit 302, a mapping unit 303, a reception signal processing unit 304, and a measurement unit 305. Note that these configurations only need to be included in base station 10, and some or all of the configurations need not be included in baseband signal processing section 104.

The control unit (scheduler) 301 controls the entire base station 10. The control unit 301 can be configured from a controller, a control circuit, or a control device described based on common recognition in the technical field according to the present disclosure.

The control unit 301 controls, for example, signal generation in the transmission signal generation unit 302, signal assignment in the mapping unit 303, and the like. Further, the control unit 301 controls a signal reception process in the reception signal processing unit 304, a signal measurement in the measurement unit 305, and the like.

The control unit 301 performs scheduling (for example, resource transmission) of system information, a downlink data signal (for example, a signal transmitted on the PDSCH), and a downlink control signal (for example, a signal transmitted on the PDCCH and / or the EPDCCH; Quota). Further, control section 301 controls generation of a downlink control signal, a downlink data signal, and the like based on a result of determining whether or not retransmission control is required for an uplink data signal.

The control unit 301 controls the scheduling of a synchronization signal (for example, PSS / SSS) and a downlink reference signal (for example, CRS, CSI-RS, DMRS).

The control unit 301 controls to form a transmission beam and / or a reception beam using digital BF (for example, precoding) by the baseband signal processing unit 104 and / or analog BF (for example, phase rotation) by the transmission / reception unit 103. May be performed.

Transmission signal generation section 302 generates a downlink signal (downlink control signal, downlink data signal, downlink reference signal, etc.) based on an instruction from control section 301, and outputs the generated signal to mapping section 303. The transmission signal generation unit 302 can be configured from a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present disclosure.

The transmission signal generation unit 302 generates a DL assignment for notifying downlink data allocation information and / or a UL grant for notifying uplink data allocation information, based on an instruction from the control unit 301, for example. The DL assignment and the UL grant are both DCI and follow the DCI format. In addition, the downlink data signal is subjected to an encoding process, a modulation process, and the like according to an encoding rate, a modulation scheme, and the like determined based on channel state information (CSI: Channel \ State \ Information) from each user terminal 20 and the like.

Mapping section 303 maps the downlink signal generated by transmission signal generation section 302 to a predetermined radio resource based on an instruction from control section 301, and outputs the result to transmission / reception section 103. The mapping unit 303 can be configured by a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present disclosure.

(4) The reception signal processing unit 304 performs reception processing (for example, demapping, demodulation, and decoding) on the reception signal input from the transmission / reception unit 103. Here, the received signal is, for example, an uplink signal (uplink control signal, uplink data signal, uplink reference signal, etc.) transmitted from the user terminal 20. The reception signal processing unit 304 can be configured from a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present disclosure.

(4) The reception signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, when a PUCCH including HARQ-ACK is received, HARQ-ACK is output to control section 301. Further, the reception signal processing unit 304 outputs the reception signal and / or the signal after the reception processing to the measurement unit 305.

The measurement unit 305 performs measurement on the received signal. The measurement unit 305 can be configured from a measurement device, a measurement circuit, or a measurement device described based on common recognition in the technical field according to the present disclosure.

For example, the measurement unit 305 may perform RRM (Radio Resource Management) measurement, CSI (Channel State Information) measurement, or the like based on the received signal. Measuring section 305 receives power (for example, RSRP (Reference Signal Received Power)), reception quality (for example, RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), SNR (Signal to Noise Ratio)). , Signal strength (for example, RSSI (Received Signal Strength Indicator)), channel information (for example, CSI), and the like may be measured. The measurement result may be output to the control unit 301.

Note that the transmission / reception section 103 may further include an analog beamforming section that performs analog beamforming. The analog beamforming unit can be configured from an analog beamforming circuit (for example, a phase shifter, a phase shift circuit) described based on common recognition in the technical field according to the present disclosure. In addition, the transmission / reception antenna 101 can be configured by, for example, an array antenna. Further, the transmission / reception unit 103 may be configured to be able to apply a single BF, a multi BF, or the like.

Transceiving section 103 may transmit a signal using a transmission beam or receive a signal using a reception beam. The control unit 301 controls to form at least one of a transmission beam and a reception beam by using digital BF (for example, precoding) by the baseband signal processing unit 104 and analog BF (for example, phase rotation) by the transmission and reception unit 103. May be performed.

The control unit 301 may control RLM, BFR, and the like for the user terminal 20. The transmission / reception unit 103 may transmit a reference signal (BFD-RS: Beam \ Failure \ Detection \ Reference \ Signal) for detecting a beam failure.

(User terminal)
FIG. 8 is a diagram illustrating an example of the overall configuration of the user terminal according to the embodiment. The user terminal 20 includes a plurality of transmitting / receiving antennas 201, an amplifier unit 202, a transmitting / receiving unit 203, a baseband signal processing unit 204, and an application unit 205. The transmitting / receiving antenna 201, the amplifier unit 202, and the transmitting / receiving unit 203 may be configured to include at least one each.

(4) The radio frequency signal received by the transmitting / receiving antenna 201 is amplified by the amplifier unit 202. The transmission / reception unit 203 receives the downlink signal amplified by the amplifier unit 202. The transmitting / receiving section 203 converts the frequency of the received signal into a baseband signal and outputs the baseband signal to the baseband signal processing section 204. The transmission / reception unit 203 can be configured from a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device described based on common recognition in the technical field according to the present disclosure. Note that the transmission / reception unit 203 may be configured as an integrated transmission / reception unit, or may be configured from a transmission unit and a reception unit.

The baseband signal processing unit 204 performs FFT processing, error correction decoding, reception processing for retransmission control, and the like on the input baseband signal. The downlink user data is transferred to the application unit 205. The application unit 205 performs processing related to layers higher than the physical layer and the MAC layer. Also, of the downlink data, broadcast information may be transferred to the application unit 205.

On the other hand, uplink user data is input from the application unit 205 to the baseband signal processing unit 204. The baseband signal processor 204 performs retransmission control transmission processing (eg, HARQ transmission processing), channel coding, precoding, discrete Fourier transform (DFT) processing, IFFT processing, and the like, and performs transmission / reception processing. Transferred to 203.

(4) The transmission / reception unit 203 converts the baseband signal output from the baseband signal processing unit 204 into a radio frequency band and transmits the radio frequency band. The radio frequency signal frequency-converted by the transmitting / receiving section 203 is amplified by the amplifier section 202 and transmitted from the transmitting / receiving antenna 201.

FIG. 9 is a diagram illustrating an example of a functional configuration of the user terminal according to the embodiment. Note that, in this example, functional blocks of characteristic portions in the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication.

The baseband signal processing unit 204 of the user terminal 20 includes at least a control unit 401, a transmission signal generation unit 402, a mapping unit 403, a reception signal processing unit 404, and a measurement unit 405. Note that these configurations need only be included in the user terminal 20, and some or all of the configurations need not be included in the baseband signal processing unit 204.

The control unit 401 controls the entire user terminal 20. The control unit 401 can be configured from a controller, a control circuit, or a control device described based on common recognition in the technical field according to the present disclosure.

The control unit 401 controls, for example, signal generation in the transmission signal generation unit 402, signal assignment in the mapping unit 403, and the like. Further, the control unit 401 controls a signal reception process in the reception signal processing unit 404, a signal measurement in the measurement unit 405, and the like.

The control unit 401 acquires the downlink control signal and the downlink data signal transmitted from the base station 10 from the reception signal processing unit 404. The control unit 401 controls generation of an uplink control signal and / or an uplink data signal based on a result of determining whether or not retransmission control is required for a downlink control signal and / or a downlink data signal.

When the control unit 401 acquires various information notified from the base station 10 from the reception signal processing unit 404, the control unit 401 may update parameters used for control based on the information.

Transmission signal generation section 402 generates an uplink signal (uplink control signal, uplink data signal, uplink reference signal, etc.) based on an instruction from control section 401 and outputs the generated signal to mapping section 403. The transmission signal generation unit 402 can be configured from a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present disclosure.

(4) The transmission signal generation unit 402 generates an uplink control signal related to acknowledgment information, channel state information (CSI), and the like based on an instruction from the control unit 401, for example. Further, transmission signal generating section 402 generates an uplink data signal based on an instruction from control section 401. For example, the transmission signal generation unit 402 is instructed by the control unit 401 to generate an uplink data signal when the downlink control signal notified from the base station 10 includes a UL grant.

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

(4) The reception signal processing unit 404 performs reception processing (for example, demapping, demodulation, and decoding) on the reception signal input from the transmission / reception unit 203. Here, the received signal is, for example, a downlink signal (a downlink control signal, a downlink data signal, a downlink reference signal, etc.) transmitted from the base station 10. The reception signal processing unit 404 can be configured from a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present disclosure. In addition, the reception signal processing unit 404 can configure a reception unit according to the present disclosure.

(4) The reception signal processing unit 404 outputs the information decoded by the reception processing to the control unit 401. The reception signal processing unit 404 outputs, for example, broadcast information, system information, RRC signaling, DCI, and the like to the control unit 401. Further, the reception signal processing unit 404 outputs the reception signal and / or the signal after the reception processing to the measurement unit 405.

The measuring unit 405 measures the received signal. The measurement unit 405 can be configured from a measurement device, a measurement circuit, or a measurement device described based on common recognition in the technical field according to the present disclosure.

For example, the measurement unit 405 may perform RRM measurement, CSI measurement, and the like based on the received signal. The measurement unit 405 may measure reception power (for example, RSRP), reception quality (for example, RSRQ, SINR, SNR), signal strength (for example, RSSI), and channel information (for example, CSI). The measurement result may be output to the control unit 401.

Note that the transmission / reception unit 203 may further include an analog beamforming unit that performs analog beamforming. The analog beamforming unit can be configured from an analog beamforming circuit (for example, a phase shifter, a phase shift circuit) described based on common recognition in the technical field according to the present disclosure. In addition, the transmission / reception antenna 201 can be configured by, for example, an array antenna. Further, the transmission / reception unit 203 may be configured so that a single BF, a multi BF, or the like can be applied.

The transmission / reception unit 203 may transmit a signal using a transmission beam, or may receive a signal using a reception beam. The control unit 401 controls to form at least one of a transmission beam and a reception beam by using digital BF (for example, precoding) by the baseband signal processing unit 204 and analog BF (for example, phase rotation) by the transmission and reception unit 203. May be performed.

The transmission / reception unit 203 may receive a reference signal (BFD-RS: Beam Failure Detection Reference Signal) for beam failure detection. The control unit 401 may control radio link monitoring (RLM: Radio Link Monitoring), beam failure recovery (BFR: Beam Failure Recovery), and the like based on the measurement result of the measurement unit 405. The transmission / reception unit 203 may transmit BFRQ or the like to the base station 10.

The control unit 401 determines whether a plurality of CORESETs (Control RESET SET) greater than a predetermined number (for example, 2) are set and a set of reference signal indices corresponding to the BFD-RS resources is not set by higher layer signaling. The reference signal indexes up to the predetermined number to be included in the set may be determined based on a TCI (Transmission Configuration Indication) state set in each coreset.

When only one or two coresets among the plurality of coresets include a TCI state having up to two reference signal indices, the control unit 401 may control the two or more coresets of the one or two coresets. A reference signal index may be included in the set.

If the plurality of coresets have a total of more reference signal indices than the predetermined number (for example, the number of active TCI states is greater than the predetermined number over these coresets), the control unit 401 determines the following ( The reference signal indexes included in up to two coresets determined based on the order (priority order) of any one of (1), (2) and (3) or a combination thereof may be included in the set. :
(1) CORRESET in which one RS is set in one TCI state,
(2) Two RSs are set in one TCI state, one of which is a RESET corresponding to the relationship of QCL type D,
(3) CORESET corresponding to a (lower) CORESET ID.

The control unit 401 may determine the reference signal index up to the predetermined number for each CORESET.

(Hardware configuration)
Note that the block diagram used in the description of the above-described embodiment shows blocks in functional units. These functional blocks (components) are realized by an arbitrary combination of at least one of hardware and software. In addition, a method of implementing each functional block is not particularly limited. That is, each functional block may be realized using one device physically or logically coupled, or directly or indirectly (for example, two or more devices physically or logically separated). , Wired, wireless, etc.), and may be implemented using these multiple devices. The functional block may be realized by combining one device or the plurality of devices with software.

Here, the functions include judgment, determination, judgment, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, and deemed. , Broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc. Not limited. For example, a functional block (configuration unit) that causes transmission to function may be referred to as a transmitting unit (transmitting unit), a transmitter (transmitter), or the like. In any case, as described above, the realization method is not particularly limited.

For example, a base station, a user terminal, or the like according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method according to the present disclosure. FIG. 10 is a diagram illustrating an example of a hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. .

In the present disclosure, the terms such as “apparatus”, “circuit”, “device”, “section”, and “unit” can be read interchangeably. The hardware configuration of the base station 10 and the user terminal 20 may be configured to include one or more of the devices illustrated in the drawing, or may be configured to exclude some of the devices.

For example, although only one processor 1001 is illustrated, there may be multiple processors. Further, the processing may be executed by one processor, or the processing may be executed by two or more processors simultaneously, sequentially, or by using another method. Note that the processor 1001 may be implemented by one or more chips.

The functions of the base station 10 and the user terminal 20 are performed, for example, by reading predetermined software (program) on hardware such as the processor 1001 and the memory 1002 so that the processor 1001 performs an arithmetic operation and communicates via the communication device 1004. And 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: Central Processing Unit) including an interface with a peripheral device, a control device, an arithmetic device, a register, and the like. For example, the above-described baseband signal processing unit 104 (204), call processing unit 105, and the like may be realized by the processor 1001.

The processor 1001 reads out a program (program code), a software module, data, and the like from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operation described in the above embodiment is used. For example, the control unit 401 of the user terminal 20 may be implemented by a control program stored in the memory 1002 and operated by the processor 1001, and other functional blocks may be implemented similarly.

The memory 1002 is a computer-readable recording medium, for example, at least one of ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically EPROM), RAM (Random Access Memory), and other appropriate storage media. It may be constituted by one. The memory 1002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, and the like that can be executed to execute the wireless communication method according to an embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium such as a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (for example, a compact disk (CD-ROM (Compact Disc) ROM, etc.), a digital versatile disc, At least one of a Blu-ray (registered trademark) disk, a removable disk, a hard disk drive, a smart card, a flash memory device (eg, a card, a stick, a key drive), a magnetic stripe, a database, a server, and other suitable storage media. May be configured. The storage 1003 may be called an auxiliary 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, for example, a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes 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: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex). May be configured. For example, the transmission / reception antenna 101 (201), the amplifier unit 102 (202), the transmission / reception unit 103 (203), the transmission path interface 106, and the like may be realized by the communication device 1004. The transmission / reception unit 103 (203) may be physically or logically separated from the transmission unit 103a (203a) and the reception unit 103b (203b).

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

The devices such as the processor 1001 and the memory 1002 are connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using a different bus for each device.

In addition, the base station 10 and the user terminal 20 include hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). It may be configured to include hardware, and some or all of the functional blocks may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

(Modification)
Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meaning. For example, channels, symbols and signals (signals or signaling) may be read interchangeably. Also, the signal may be a message. The reference signal may be abbreviated as RS (Reference Signal), and may be referred to as a pilot, a pilot signal, or the like according to an applied standard. A component carrier (CC: Component Carrier) may be called a cell, a frequency carrier, a carrier frequency, or the like.

A radio frame may be configured by one or more periods (frames) in the time domain. The one or more respective periods (frames) forming the radio frame may be referred to as a subframe. Further, a subframe may be configured by one or more slots in the time domain. The subframe may be of a fixed length of time (eg, 1 ms) that does not depend on numerology.

Here, the new melology may be a communication parameter applied to at least one of transmission and reception of a certain signal or channel. Numerology includes, for example, subcarrier interval (SCS: SubCarrier @ Spacing), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI: Transmission @ Time @ Interval), number of symbols per TTI, radio frame configuration, transmission and reception. At least one of a specific filtering process performed by the transceiver in the frequency domain and a specific windowing process performed by the transceiver in the time domain may be indicated.

The slot may be configured by one or a plurality of symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol, etc.) in the time domain. Further, the slot may be a time unit based on numerology.

The slot may include a plurality of mini slots. Each minislot may be constituted by one or more symbols in the time domain. Also, the mini-slot may be called a sub-slot. A minislot may be made up of a smaller number of symbols than slots. A PDSCH (or PUSCH) transmitted in time units larger than minislots may be referred to as PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be referred to as a PDSCH (PUSCH) mapping type B.

Radio frames, subframes, slots, minislots, and symbols all represent time units when transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may have different names corresponding to each. Note that time units such as frames, subframes, slots, minislots, and symbols in the present disclosure may be interchanged with each other.

For example, one subframe may be called a transmission time interval (TTI: Transmission @ Time @ Interval), a plurality of consecutive subframes may be called a TTI, and one slot or one minislot is called a TTI. You may. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in the existing LTE, a period shorter than 1 ms (for example, 1 to 13 symbols), or a period longer than 1 ms. It may be. Note that the unit representing the TTI may be called a slot, a minislot, or the like instead of a subframe.

Here, the TTI refers to, for example, a minimum time unit of scheduling in wireless communication. For example, in the LTE system, the base station performs scheduling for allocating radio resources (frequency bandwidth, transmission power, and the like that can be used in each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

The TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, or a code word, or may be a processing unit such as scheduling and link adaptation. Note that when a TTI is given, a time section (for example, the number of symbols) in which a transport block, a code block, a codeword, and the like are actually mapped may be shorter than the TTI.

If one slot or one minislot is called a TTI, one or more TTIs (ie, one or more slots or one or more minislots) may be the minimum time unit for scheduling. Further, the number of slots (mini-slot number) constituting the minimum time unit of the scheduling may be controlled.

A TTI having a time length of 1 ms may be referred to as a normal TTI (TTI in LTE@Rel.8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, and the like. A TTI shorter than the normal TTI may be called a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a minislot, a subslot, a slot, and the like.

Note that a long TTI (for example, a normal TTI, a subframe, etc.) may be read as a TTI having a time length exceeding 1 ms, and a short TTI (for example, a shortened TTI, etc.) may be replaced with a TTI shorter than the long TTI and 1 ms. The TTI having the above-described TTI length may be replaced with the TTI.

A resource block (RB: Resource Block) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in the RB may be the same irrespective of the numerology, and may be, for example, 12. The number of subcarriers included in the RB may be determined based on numerology.

Ｒ Also, the RB may include one or more symbols in the time domain, and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, and the like may each be configured by one or a plurality of resource blocks.

Note that one or more RBs include a physical resource block (PRB: Physical @ RB), a subcarrier group (SCG: Sub-Carrier @ Group), a resource element group (REG: Resource @ Element @ Group), a PRB pair, an RB pair, and the like. May be called.

{Also, a resource block may be composed of one or more resource elements (RE: Resource @ Element). For example, one RE may be a radio resource area of one subcarrier and one symbol.

A bandwidth part (BWP: Bandwidth @ Part) (which may be referred to as a partial bandwidth or the like) may also represent a subset of consecutive common RBs (common @ resource @ blocks) for a certain numerology in a certain carrier. Good. Here, the common RB may be specified by an index of the RB based on the common reference point of the carrier. A PRB may be defined by a BWP and numbered within the BWP.

$ BWP may include a BWP for UL (UL @ BWP) and a BWP for DL (DL @ BWP). For a UE, one or more BWPs may be configured in one carrier.

少なくとも At least one of the configured BWPs may be active, and the UE does not have to assume to transmit and receive a given signal / channel outside the active BWP. Note that “cell”, “carrier”, and the like in the present disclosure may be replaced with “BWP”.

The structures of the above-described radio frame, subframe, slot, minislot, symbol, and the like are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, included in an RB The configuration of the number of subcarriers, the number of symbols in the TTI, the symbol length, the cyclic prefix (CP: Cyclic @ Prefix) length, and the like can be variously changed.

Further, the information, parameters, and the like described in the present disclosure may be expressed using an absolute value, may be expressed using a relative value from a predetermined value, or may be expressed using another corresponding information. May be represented. For example, a radio resource may be indicated by a predetermined index.

名称 Names used for parameters and the like in the present disclosure are not limited in any respect. Further, the formulas and the like using these parameters may be different from those explicitly disclosed in the present disclosure. The various channels (PUCCH (Physical Uplink Control Channel), PDCCH (Physical Downlink Control Channel), etc.) and information elements can be identified by any suitable name, so the various names assigned to these various channels and information elements Is not a limiting name in any way.

The 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, chips, etc., that can be referred to throughout the above description are not limited to voltages, currents, electromagnetic waves, magnetic or magnetic particles, optical or photons, or any of these. May be represented by a combination of

情報 In addition, information, signals, and the like can be output from the upper layer to at least one of the lower layer and the lower layer to the upper layer. Information, signals, etc. may be input / output via a plurality of network nodes.

(4) Information and signals input and output may be stored in a specific place (for example, a memory) or may be managed using a management table. Information and signals that are input and output can be overwritten, updated, or added. The output information, signal, and the like may be deleted. The input information, signal, and the like may be transmitted to another device.

Notification of information is not limited to the aspect / embodiment described in the present disclosure, and may be performed using another method. For example, the information is notified by physical layer signaling (for example, downlink control information (DCI: Downlink Control Information), uplink control information (UCI: Uplink Control Information)), higher layer signaling (for example, RRC (Radio Resource Control) signaling, It may be implemented by broadcast information (master information block (MIB: Master Information Block), system information block (SIB: System Information Block), etc.), MAC (Medium Access Control) signaling), other signals, or a combination thereof.

Note that the physical layer signaling may be called L1 / L2 (Layer 1 / Layer 2) control information (L1 / L2 control signal), L1 control information (L1 control signal), or 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. Also, the MAC signaling may be notified using, for example, a MAC control element (MAC @ CE (Control @ Element)).

Further, the notification of the predetermined information (for example, the notification of “X”) is not limited to an explicit notification, and is implicit (for example, by not performing the notification of the predetermined information or by another information). May be performed).

The determination may be made by a value represented by 1 bit (0 or 1), or may be made by a boolean value represented by true or false. , May be performed by comparing numerical values (for example, comparison with a predetermined value).

Software, regardless of whether it is called software, firmware, middleware, microcode, a hardware description language, or any other name, instructions, instruction sets, codes, code segments, program codes, programs, subprograms, software modules , Applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like.

ソフトウェア Also, software, instructions, information, and the like may be transmitted and received via a transmission medium. For example, if the software uses at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and wireless technology (infrared, microwave, etc.), the website, When transmitted from a server or other remote source, at least one of these wired and / or wireless technologies is included within the definition of a transmission medium.

用語 The terms “system” and “network” as used in this disclosure may be used interchangeably.

In the present disclosure, “precoding”, “precoder”, “weight (precoding weight)”, “quasi-co-location (QCL)”, “TCI state (Transmission Configuration Indication state)”, “spatial relation” (Spatial relation), "spatial domain filter", "transmission power", "phase rotation", "antenna port", "antenna port group", "layer", "number of layers", " Terms such as "rank", "resource", "resource set", "resource group", "beam", "beam width", "beam angle", "antenna", "antenna element", "panel" are interchangeable Can be used for

In the present disclosure, “base station (BS: Base @ Station)”, “wireless base station”, “fixed station (fixed @ station)”, “NodeB”, “eNodeB (eNB)”, “gNodeB (gNB)”, “gNodeB (gNB)” "Access point (access @ point)", "transmission point (TP: Transmission @ Point)", "reception point (RP: Reception @ Point)", "transmission / reception point (TRP: Transmission / Reception @ Point)", "panel", "cell" , "Sector", "cell group", "carrier", "component carrier" and the like may be used interchangeably. A base station may also be referred to as a macro cell, a small cell, a femto cell, a pico cell, or the like.

A base station can accommodate one or more (eg, three) cells. If the base station accommodates multiple cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station (RRH: Communication services can also be provided by Remote Radio Head)). The term "cell" or "sector" refers to part or all of the coverage area of at least one of a base station and a base station subsystem that provides communication services in this coverage.

In the present disclosure, terms such as “mobile station (MS)”, “user terminal”, “user equipment” (UE), and “terminal” may be used interchangeably. .

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

少なくとも At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, or the like. Note that at least one of the base station and the mobile station may be a device mounted on the mobile unit, the mobile unit itself, or the like. The moving object may be a vehicle (for example, a car, an airplane, or the like), may be an unmanned moving object (for example, a drone, an autonomous vehicle), or may be a robot (maned or unmanned). ). Note that 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 IoT (Internet of Things) device such as a sensor.

基地 Also, the base station in the present disclosure may be replaced with a user terminal. For example, communication between a base station and a user terminal is replaced with communication between a plurality of user terminals (for example, may be called D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). Each aspect / embodiment of the present disclosure may be applied to the configuration. In this case, the configuration may be such that the user terminal 20 has the function of the base station 10 described above. Further, words such as “up” and “down” may be read as words corresponding to communication between terminals (for example, “side”). For example, an uplink channel, a downlink channel, and the like may be replaced with a side channel.

Similarly, the user terminal in the present disclosure may be replaced with a base station. In this case, a configuration in which the base station 10 has the function of the user terminal 20 described above may be adopted.

In the present disclosure, the operation performed by the base station may be performed by an upper node (upper node) in some cases. In a network including one or more network nodes having a base station (network @ nodes), various operations performed for communication with a terminal include a base station, one or more network nodes other than the base station (eg, Obviously, it can be performed by MME (Mobility Management Entity), S-GW (Serving-Gateway) or the like, but not limited thereto, or a combination thereof.

各 Each aspect / embodiment described in the present disclosure may be used alone, may be used in combination, or may be used by switching with execution. In addition, the processing procedures, sequences, flowcharts, and the like of each aspect / embodiment described in the present disclosure may be interchanged in order as long as there is no inconsistency. For example, for the methods described in this disclosure, elements of various steps are presented in an exemplary order, and are not limited to the specific order presented.

Each aspect / embodiment described in the present disclosure is applicable to LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication). system, 5G (5th generation mobile communication system), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New radio access), FX (Future generation radio access), GSM (Registered trademark) (Global System for Mobile Communications), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802. 20, UWB (Ultra-WideBand), Bluetooth (registered trademark) , A system using other appropriate wireless communication methods, and a next-generation system extended based on these methods. Further, a plurality of systems may be combined (for example, a combination of LTE or LTE-A and 5G) and applied.

記載 The term “based on” as used in the present disclosure does not mean “based on” unless otherwise indicated. In other words, the phrase "based on" means both "based only on" and "based at least on."

いかなる Any reference to elements using designations such as "first," "second," etc., as used in this disclosure, does not generally limit the quantity or order of those elements. These designations may be used in the present disclosure as a convenient way to distinguish between two or more elements. Thus, reference to a first and second element does not mean that only two elements can be employed or that the first element must precede the second element in any way.

用語 The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, “judgment (decision)” means judging, calculating, computing, processing, deriving, investigating, searching (upping, searching, inquiry) ( For example, a search in a table, database, or another data structure), ascertaining, etc., may be regarded as "deciding".

Also, “determining” includes receiving (eg, receiving information), transmitting (eg, transmitting information), input (input), output (output), and access ( accessing) (e.g., accessing data in a memory) or the like.

Also, “judgment (decision)” is regarded as “judgment (decision)” of resolving, selecting, selecting, establishing, comparing, etc. Is also good. That is, “judgment (decision)” may be regarded as “judgment (decision)” of any operation.

判断 Also, “judgment (decision)” may be read as “assuming”, “expecting”, “considering”, or the like.

As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements. And may include the presence of one or more intermediate elements between two elements "connected" or "coupled" to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. For example, “connection” may be read as “access”.

In this disclosure, where two elements are connected, using one or more wires, cables, printed electrical connections, etc., and as some non-limiting and non-exhaustive examples, the radio frequency domain, microwave It can be considered to be "connected" or "coupled" to each other using electromagnetic energy having a wavelength in the region, light (both visible and invisible) regions, and the like.

において In the present disclosure, the term “A and B are different” may mean that “A and B are different from each other”. The term may mean that “A and B are different from C”. Terms such as "separate", "coupled" and the like may be interpreted similarly to "different".

Where the terms “include”, “including” and variations thereof are used in the present disclosure, these terms are as inclusive as the term “comprising” Is intended. Further, the term "or" as used in the present disclosure is not intended to be an exclusive or.

In the present disclosure, where articles are added by translation, for example, a, an, and the in English, the present disclosure may include that the nouns following 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 changes without departing from the spirit and scope of the invention determined based on the description of the claims. Therefore, the description of the present disclosure is intended for illustrative purposes and does not bring any restrictive meaning to the invention according to the present disclosure.

Claims

A receiving unit that receives a reference signal (BFD-RS: Beam Failure Detection Reference Signal) for detecting a beam failure;
When a plurality of CORESETs (Control Resource SETs) that are larger than a predetermined number are set, and when a set of reference signal indices corresponding to the BFD-RS resources is not set by higher layer signaling, a TCI (Transmission) set for each CORESET is set. A control unit configured to determine up to the predetermined number of reference signal indices to be included in the set based on a state of Configuration Indication.
The controller may be configured to, if only one or two of the plurality of CORESETs include a TCI state having up to two reference signal indices, determine whether or not the two or more CORESETs have the same TCI state. The user terminal according to claim 1, wherein a reference signal index is included in the set.
When the plurality of CORESETs have a reference signal index that is greater than the predetermined number in total, the control unit may determine any one of the following (1), (2), and (3) or a combination of the following: 3. The user terminal according to claim 1, wherein the reference signal index included in up to two coresets determined based on the reference is included in the set. 4.
(1) CORRESET in which one RS is set in one TCI state,
(2) Two RSs are set in one TCI state, one of which is a RESET corresponding to the relationship of QCL type D,
(3) CORESET corresponding to a (lower) CORESET ID.
2. The user terminal according to claim 1, wherein the control unit determines the reference signal indexes up to the predetermined number for each reset.
Receiving a reference signal (BFD-RS: Beam Failure Detection Reference Signal) for beam failure detection;
When a plurality of CORESETs (Control Resource SETs) that are larger than a predetermined number are set and a set of reference signal indices corresponding to the BFD-RS resources is not set by higher layer signaling, a TCI (Transmission) set for each CORESET is set. Determining a reference signal index up to the predetermined number to be included in the set based on a configuration indication state.