阅读说明：本技术 用户终端以及无线通信方法 (User terminal and wireless communication method ) 是由 松村祐辉 武田一树 永田聪 于 2018-08-09 设计创作，主要内容包括：关于在构成为在将来的无线通信系统的波束恢复过程中,监视除了对于波束恢复请求的应答信号(BFRQR)用的搜索空间以外的搜索空间的情况下的恰当的设定,本公开的用户终端的一方式具有：控制单元,根据对于波束恢复请求的应答信号用的第一搜索空间被设定的载波,控制与所述第一搜索空间以及除了所述第一搜索空间以外的第二搜索空间相关的监视设定；以及接收单元,基于所述设定,监视所述第一搜索空间以及所述第二搜索空间的至少一方。(Regarding an appropriate setting in a case where a search space other than a search space for a response signal (BFRQR) to a beam recovery request is monitored during beam recovery in a future wireless communication system, an embodiment of a user terminal according to the present disclosure includes: a control unit configured to control monitoring settings related to a first search space and a second search space other than the first search space, based on a carrier for which the first search space for a response signal to a beam recovery request is set; and a receiving unit that monitors at least one of the first search space and the second search space based on the setting.)

1. A user terminal, comprising:

a control unit configured to control monitoring settings related to a first search space and a second search space other than the first search space, based on a carrier for which the first search space for a response signal to a beam recovery request is set; and

and a receiving unit configured to monitor at least one of the first search space and the second search space based on the setting.

2. The user terminal of claim 1,

the control unit controls the setting on the condition that whether the first search space and the second search space have the same subcarrier spacing.

3. The user terminal of claim 1,

the control unit controls the setting on the condition that whether the first search space and the second search space are of Quasi-Co-location (QCL) type D.

4. The user terminal of claim 1,

the control unit controls the setting on the condition that whether the second search space is a common search space.

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

the control unit controls a monitoring setting related to a search space so as not to be based on the setting after detection of a response signal to the beam recovery request.

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

controlling a monitor setting relating to a first search space and a second search space other than the first search space, based on a carrier in which the first search space for a response signal to a beam recovery request is set; and

and monitoring at least one of the first search space and the second search space based on the setting.

Technical Field

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

Background

In a conventional LTE system (e.g., rel.8-14), Radio Link Monitoring (RLM), which is a Monitoring of Radio Link quality, is performed. When Radio Link Failure (RLF) is detected by Radio Link Monitoring (RLM), a User Equipment (UE) is requested to reestablish an RRC (Radio Resource Control) connection (re-establishment).

Documents of the prior art

Non-patent document

Non-patent document 1: 3GPP TS 36.300V14.5.0 "Evolved Universal Radio Access (E-UTRA) and Evolved Universal Radio Access Network (E-UTRAN); (ii) an Overall description; stage 2(Release 14) ", 12 months in 2017

Disclosure of Invention

Problems to be solved by the invention

In future wireless communication systems (e.g., rel.15, New Radio (NR))) research is underway: in order to suppress the occurrence of Radio Link Failure (RLF), when the quality of a specific beam is deteriorated, a handover procedure to another beam is performed.

In the Beam Recovery procedure of a future wireless communication system, it is not clear whether or not a user terminal monitors a search space other than a search space for a response signal (BFRQ Request (BFRQR)) of a Beam Recovery Request (Beam Failure Recovery Request (BFRQ)).

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a user terminal and a radio communication method that can control appropriate settings in a case where a search space other than a search space for a response signal (BFRQR) to a beam recovery request is monitored in a beam recovery procedure of a future radio communication system.

Means for solving the problems

An aspect of the user terminal of the present invention is characterized by including: a control unit configured to control monitoring settings related to a first search space and a second search space other than the first search space, based on a carrier for which the first search space for a response signal to a beam recovery request is set; and a receiving unit that monitors at least one of the first search space and the second search space based on the setting.

Effects of the invention

According to the present invention, in the beam recovery procedure of a future wireless communication system, it is possible to control appropriate settings in a case where the search space is configured to monitor a search space other than the search space for the response signal (BFRQR) to the beam recovery request.

Drawings

Fig. 1 is a diagram illustrating an example of a beam recovery procedure in a future wireless communication system.

Fig. 2 is a diagram showing a RAR window in initial access versus search space.

Fig. 3A and 3B are diagrams illustrating a scenario assumed when a user terminal can simultaneously receive a plurality of beams.

Fig. 4 is a diagram showing an example of a schematic configuration of a radio communication system according to the present embodiment.

Fig. 5 is a diagram showing an example of a functional configuration of the radio base station according to the present embodiment.

Fig. 6 is a diagram showing an example of a functional configuration of a baseband signal processing unit of the radio base station.

Fig. 7 is a diagram showing an example of a functional configuration of a user terminal according to the present embodiment.

Fig. 8 is a diagram showing an example of a functional configuration of a baseband signal processing unit of a user terminal.

Fig. 9 is a diagram showing an example of hardware configurations of a radio base station and a user terminal according to an embodiment of the present invention.

Detailed Description

In future wireless communication systems (e.g., 5G +, NR, rel.15 and beyond), research is underway: communication is performed using beamforming (Beam Forming (BF)). In order to improve communication quality using Beamforming (BF), at least one of transmission and reception of signals is controlled in consideration of a Quasi-Co-location (QCL) relationship between a plurality of signals.

Quasi co-location (QCL) refers to an indicator that represents the nature of the statistics of a channel. For example, in the case where a certain signal or channel and another signal or channel are in a quasi-co-location (QCL) relationship, it may be assumed that (assuming, the association) is such that at least 1 of doppler shift, doppler spread, average delay, delay spread, and spatial parameters (e.g., spatial reception parameters) is the same among these different signals or channels, that is, at least 1 of these signals or channels is quasi-co-location (QCL).

The spatial reception parameters may also correspond to reception beams (e.g., reception analog beams) of the user terminal, and the beams may also be determined based on QCLs of the space. QCLs and elements of at least 1 of QCLs in the present disclosure may also be replaced with sqcls (spatial QCLs).

With regard to QCLs, multiple QCL types may also be specified. For example, with respect to parameters or parameter sets (parameter sets) that can be assumed to be the same, 4 different QCL types (QCL type a to QCL type D) may also be provided.

QCL type a is a QCL that can be assumed to be identical in doppler shift, doppler spread, average delay, and delay spread.

QCL type B is a QCL that can be assumed to be the same in doppler shift and doppler spread.

QCL type C is a QCL that can be assumed to have the same average delay and doppler shift.

QCL type D is a QCL whose spatial reception parameters can be assumed to be the same.

In future wireless communication systems, research is being conducted: the Transmission/reception processing of the channel is controlled based on the state (TCI state) of a Transmission Configuration Indicator (TCI).

The TCI status may also represent QCL information. Alternatively, the TCI status may also contain QCL information. For example, at least one of the TCI status and the QCL information may be information on the QCL of the target channel, the reference signal for the channel, and another signal (e.g., another downlink reference signal). For example, the information on the QCL may include at least one of information on a downlink reference signal to be the QCL and information indicating the QCL type.

When Beamforming (BF) is used, since the BF is susceptible to interference caused by obstacles, the quality of a radio link may be deteriorated, and Radio Link Failure (RLF) may frequently occur. Since reconnection of a cell is required when Radio Link Failure (RLF) occurs, the occurrence of frequent Radio Link Failure (RLF) causes a drop in system throughput.

In future wireless communication systems (e.g., NR), research is being conducted: in order to suppress the occurrence of Radio Link Failure (RLF), when the quality of a specific beam is deteriorated, a handover procedure to another beam is performed. The switching process to another Beam may be referred to as Beam Recovery (BR)), Beam Failure Recovery (BFR), or L1/L2(Layer 1/Layer 2)) Beam Recovery. The Beam Failure Recovery (BFR) procedure may also be referred to as BFR for short.

A beam failure in this disclosure may also be referred to as a link failure.

Fig. 1 is a diagram showing an example of a beam recovery process of a future wireless communication system (e.g., rel.15nr). The number of beams shown in fig. 1 is an example, and is not limited thereto.

In the initial state (step S101) of fig. 1, the user terminal performs measurement based on a Reference Signal (RS) resource transmitted from a Transmission Reception Point (TRP) using 2 beams. The reference Signal may be at least one of a Synchronization Signal Block (SSB) and a Channel State measurement reference Signal (Channel State Information reference Signal (CSI-RS)). The Synchronization Signal Block (SSB) may also be referred to as an SS/PBCH (Physical Broadcast Channel) block.

The reference signal may be at least 1 of a Primary synchronization signal (Primary SS (PSS)), a Secondary Synchronization Signal (SSs), a Mobility reference signal (Mobility RS (MRS)), a Synchronization Signal Block (SSB), a signal included in the SSB, a CSI-RS, a Demodulation reference signal (Demodulation RS (DMRS)), and a beam-specific signal, or a signal obtained by extending or modifying these signals. The reference signal measured in step S101 may also be referred to as a reference signal for Beam Failure Detection (Beam Failure Detection RS (BFD-RS)).

In step S102 of fig. 1, the user terminal cannot detect the reference signal (BFD-RS) for beam failure detection because the radio wave from the transmission/reception point (TRP) is disturbed. Such a problem may occur due to, for example, an obstacle between the user terminal and the transmission/reception point (TRP), fading, interference, or the like.

When a specific condition is satisfied, the user terminal fails to detect the beam. The user terminal may detect the occurrence of a beam failure when a Block Error Rate (BLER) is less than a threshold for all reference signals (BFD-RS) set for beam failure detection (BFD-RS resource setting). When the occurrence of the beam failure is detected, the lower layer (physical layer)) of the user terminal may notify (instruct) the upper layer (MAC layer)) of the beam failure example.

The criterion (criterion) for determining the detection of the occurrence of the beam failure is not limited to the block error rate (BLER) but may be the reference signal Received Power in the physical layer (L1-RS Received Power (L1-RS Received Power (L1-RSRP))). Instead of or in addition to the Reference Signal (RS) measurement, beam failure detection may be performed based on a Downlink Control Channel (Physical Downlink Control Channel (PDCCH)) or the like. It is also contemplated that the reference signal (BFD-RS) for beam failure detection is quasi co-located (QCL) with the DMRS of the PDCCH monitored by the user terminal.

Information related to the reference signal for beam failure detection (BFD-RS), such as the index, resource, number, port number, precoding, or the like of the reference signal, and information related to Beam Failure Detection (BFD), such as the above-mentioned threshold, may be set (notified) to the user terminal by higher layer signaling. The information related to the reference signal (BFD-RS) for beam failure detection may also be referred to as information related to resources for BFD.

The higher layer signaling may be any one or a combination of 1 of RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, and broadcast information, for example.

The MAC layer of the user terminal may also start a specific timer upon receiving a beam failure instance notification from the physical layer of the user terminal. This timer may also be referred to as a beam failure detection timer. The MAC layer of the user terminal may trigger a Beam Failure Recovery (BFR) when the beam failure instance notification is received a predetermined number of times or more (e.g., a beamfailure probability max count set by RRC) until the timer expires (e.g., when starting any of the random access procedures described below).

The Transmission Reception Point (TRP) may determine that the user terminal has detected the beam failure when there is no notification from the user terminal or when a specific signal is received from the user terminal (beam recovery request in step S104).

In step S103 of fig. 1, the user terminal may restart the search for a new candidate beam (new candidate beam) to be used for communication in order to perform beam recovery. The user terminal may also select a new candidate beam corresponding to a specific Reference Signal (RS) by measuring the Reference Signal (RS). The Reference Signal (RS) measured in step S103 may also be referred to as a reference signal for New Candidate Beam Identification (New Candidate Beam Identification RS (NCBI-RS))). The reference signal (NCBI-RS) used for new candidate beam identification may be the same as or different from the reference signal (BFD-RS) used for beam failure detection. The new candidate beam may also be referred to simply as the candidate beam.

The user terminal may also determine a beam corresponding to a Reference Signal (RS) satisfying a specific condition as a new candidate beam. For example, the user terminal may determine the new candidate beam based on a Reference Signal (RS) whose reference signal received power (L1-RSRP) in the physical layer exceeds a threshold value among reference signals (NCBI-RS) for identification of the set new candidate beam. The reference (criterion) for the new candidate beam decision is not limited to L1-RSRP. The L1-RSRP associated with the Synchronization Signal Block (SSB) may also be referred to as SS-RSRP. The L1-RSRP associated with the CSI-RS may also be referred to as CSI-RSRP.

Information related to the reference signal (NCBI-RS) for new candidate beam identification, such as the resource, number, port number, precoding, or the like of the reference signal, and information related to the New Candidate Beam Identification (NCBI), such as the above-described threshold, may also be set (notified) to the user terminal via higher layer signaling. Information related to reference signals (NCBI-RS) used for new candidate beam identification may also be acquired by the user terminal based on information related to reference signals (BFD-RS) used for beam failure detection. The information related to the reference signal (NCBI-RS) for new candidate beam identification may also be referred to as information related to resources for New Candidate Beam Identification (NCBI).

The reference signal for beam failure detection (BFD-RS) and the reference signal for new candidate beam identification (NCBI-RS) may also be replaced with a Radio Link Monitoring reference signal (Radio Link Monitoring RS (RLM-RS)).

In step S104 of fig. 1, the user terminal that has determined the new candidate Beam transmits a Beam Recovery Request (BFRQ) to the Transmission Reception Point (TRP). The beam recovery request (BFRQ) may also be referred to as a beam recovery request signal or a beam failure recovery request signal, etc.

The beam recovery request (BFRQ) may be transmitted using at least 1 of, for example, an Uplink Control Channel (Physical Uplink Control Channel (PUCCH)), a Random Access Channel (Physical Random Access Channel (PRACH)), an Uplink Shared Channel (Physical Uplink Shared Channel (PUSCH)), and a set grant (configured grant) PUSCH.

The beam recovery request (BFRQ) may also contain information of the new candidate beam determined in step S103. Resources for a beam recovery request (BFRQ) may also be associated with the new candidate beam. The information of the Beam may also be notified using a Beam Index (BI)), a port Index of a specific reference signal, a resource Index (e.g., CSI-RS resource indicator), or a Synchronization Signal Block (SSB) resource indicator (SSBRI), etc.

In future wireless communication systems (e.g., rel.15nr), studies are being made to: a Contention-Based random access procedure-Based Beam Failure Recovery (BFR), that is, a CB-BFR (Contention-Based BFR), and a non-Contention-Based random access procedure-Based Beam Failure Recovery (BFR), that is, a CF-BFR (Contention-Free BFR). In CR-BFR and CF-BFR, the user terminal may also transmit a preamble as a beam recovery request (BFRQ) using PRACH resources. The preamble may also be referred to as an RA (Random Access) preamble, a Random Access channel (PRACH), or a RACH preamble.

In the beam failure recovery (CB-BFR) based on the contention-type random access procedure, the user terminal may also transmit a preamble randomly selected from 1 or more preambles. In the beam failure recovery (CF-BFR) based on the non-contention type random access procedure, the user terminal may also transmit a preamble allocated from the base station as being UE-specific. In CB-BFR, the base station may also assign the same preamble to multiple user terminals. In CF-BFR, the base station may also allocate preambles dedicated to user terminals.

The Contention-based random access procedure based beam failure recovery (CB-BFR) may also be referred to as CB PRACH-based BFR (Contention-based PRACH-based BFR (CBRA-BFR))). The beam failure recovery (CF-BFR) based on the non-Contention type random access procedure may also be referred to as a BFR based on the CF PRACH (Contention-free PRACH-based BFR (CFRA-BFR))). CBRA-BFRs may also be referred to as CBRA for BFRs. CFRA-BFRs may also be referred to as CFRA for BFRs.

In the case of the beam failure recovery (CB-BFR) based on the contention-based random access procedure, when a certain preamble is received as the beam recovery request (BFRQ), the base station may not be able to determine from which user terminal the preamble was transmitted. The base station can determine an Identifier (e.g., a Cell-Radio Network Temporary Identifier (C-RNTI)) of the user terminal that transmitted the preamble by performing contention resolution (contention resolution) from the time of the beam recovery request (BFRQ) to the time of completion of the beam reconfiguration (reconfiguration).

The signal (e.g., preamble) transmitted by the user terminal during random access may also be considered to be a beam recovery request (BFRQ).

In any of the beam failure recovery (CB-BFR) based on the contention type random access procedure and the beam failure recovery (CF-BFR) based on the non-contention type random access procedure, the information related to the PRACH resource (RA preamble) may also be notified through higher layer signaling (e.g., RRC signaling). For example, the information may include information indicating the correspondence between the detected DL-RS (beam) and the PRACH resource, or may be associated with a different PRACH resource for each DL-RS.

The detection of beam failure may also be performed in the MAC layer. With respect to the beam failure recovery (CB-BFR) based on the contention-based random access procedure, the user terminal may determine that contention resolution is successful when receiving the PDCCH corresponding to the C-RNTI associated with the user terminal.

The Random Access (RA) parameters of the beam failure recovery (CB-BFR) based on the contention type random access procedure and the beam failure recovery (CF-BFR) based on the non-contention type random access procedure may be composed of the same parameter set, or may be set to different values, respectively.

For example, the parameter (ResponseWindowSize-BFR) indicating the time length for monitoring the gNB response in the Control Resource Set (CORESET)) for the beam failure recovery response after the beam recovery request (BFRQ) may be applied to either the beam failure recovery (CB-BFR) by the contention-based random access procedure or the beam failure recovery (CF-BFR) by the non-contention-based random access procedure.

In step S105 in fig. 1, the transmission/reception point (e.g., base station) that has detected the beam recovery request (BFRQ) may transmit a response signal to the beam recovery request (BFRQ) from the user terminal. This response signal may also be referred to as a gNB response (response). The response signal may also include reconstruction information (e.g., configuration information of DL-RS resources) for 1 or more beams.

The acknowledgement signal may also be transmitted in a user terminal shared search space, e.g., PDCCH. The response signal may be notified by using an identifier of the user terminal, for example, a PDCCH scrambled with a Cyclic Redundancy Check (CRC) using a C-RNTI or Downlink Control Information (DCI). The user terminal may determine at least one of the transmission beam and the reception beam to be used, based on the beam reconstruction information.

The user terminal may also monitor the Response signal (BFRQ Response (BFRQR)) to the beam recovery request in a search space for the Response signal. The user terminal may monitor the response signal based on at least one of the CORESET for Beam Failure Recovery (BFR) and the search space set for Beam Failure Recovery (BFR).

Regarding the beam failure recovery (CB-BFR) based on the contention-based random access procedure, the user terminal may determine that contention resolution (contention resolution) is successful when receiving the PDCCH corresponding to the C-RNTI associated with the user terminal.

In the process of step S105, a period for the user terminal to monitor the response from the Transmission Reception Point (TRP) to the beam recovery request (BFRQ) may be set. This period may also be referred to as a gNB response window, a gNB window, a beam recovery request response window, or the like, for example.

In the case of beam failure recovery based on a Random Access procedure, this period may also be referred to as a Random Access Response (RAR) window.

The user terminal may retransmit the beam recovery request (BFRQ) if the detected gNB response is not received within the window period.

In future wireless communication systems, research is being conducted: the user terminal controls reception of a PDCCH mapped to a specific resource unit of the CORESET based on the TCI state indicating (or including) information related to the QCL of the CORESET.

In step S106 of fig. 1, the transmitting/receiving point (e.g., base station) sets 1 or more (K) TCI states for each CORESET by high layer signaling. The user terminal activates 1 or more TCI states using a MAC Control Element (CE) for each CORESET, respectively.

After step S106, the user terminal may transmit a message for notifying the completion of the beam reconstruction to the Transmission Reception Point (TRP). The message may also be transmitted through, for example, PUCCH or PUSCH.

The beam recovery success (BR success) may also be, for example, the case where step S106 is reached. The beam recovery failure (BR failure) may also correspond to a case where a beam recovery request (BFRQ) is transmitted up to a certain number of times, for example. The Beam failure recovery may also correspond to a case where, for example, a Beam-failure-recovery-timer (Beam-failure-recovery-timer) expires.

The numbers of the steps in fig. 1 are merely for explanation, and a plurality of steps may be collectively implemented, and the order of the steps may be changed. Whether to implement a Beam Failure Recovery (BFR) procedure may also be set to the user terminal via higher layer signaling.

In step S105 of the beam recovery procedure in the future wireless communication system shown in fig. 1, the user terminal monitors the PDCCH of the search space for the response signal (BFRQR) to the beam recovery request (BFRQ) in order to monitor the response from the transmission receiving point (e.g., base station) to the beam recovery request (BFRQ).

In the beam recovery procedure of a future wireless communication system, it is not clear whether or not the user terminal monitors a search space other than a search space for a response signal (BFRQR) to a beam recovery request.

For example, consider: in at least 1 of the section 1, the section 2, and the section 3 shown in fig. 1, the user terminal monitors a search space other than a search space associated with CORESET for Beam Failure Recovery (BFR), for example, a search space other than a search space for a response signal (BFRQR) to a beam recovery request.

Section 1 is an outer section of the gNB response window, that is, an interval from after a beam failure is detected to before a response signal for a beam recovery request (BFRQ) is received. In this interval 1, the user terminal may monitor the CORESET set before the beam failure detection without monitoring the CORESET.

Interval 2 is within the range of the gNB response window. In this section 2, the user terminal may monitor only the CORESET for the Beam Failure Recovery (BFR), or may monitor the CORESET for the Beam Failure Recovery (BFR) and the CORESET set before the beam failure detection.

Section 3 is a section after the reception of the gNB response and before the reconfiguration or activation of the PDCCH TCI state. In this section 3, the user terminal may monitor only the CORESET for the Beam Failure Recovery (BFR), or may monitor the CORESET for the Beam Failure Recovery (BFR) and the CORESET set before the beam failure detection.

In the beam recovery procedure of a future wireless communication system (e.g., rel.15nr), it is also conceivable that the user terminal cannot detect an important PDCCH when it cannot monitor a search space other than a search space for a response signal (BFRQR) to a beam recovery request.

For example, in ETWS (Earthquake and Tsunami Warning System) used for emergency Earthquake Warning or the like, whether or not System information is updated is notified by paging DCI, and the user terminal confirms the paging information and confirms the System information. Here, the Paging DCI is DCI scrambled by P-RNTI (Paging-RNTI) detected in a Paging search space (common search space).

In the beam recovery procedure of rel.15nr, it is assumed that the user terminal cannot detect an important PDCCH such as ETWS when it cannot monitor a search space other than a search space for a response signal (BFRQR) to a beam recovery request.

On the other hand, since the user terminal performs blind detection on the PDCCH, if a plurality of search spaces are set, the number of times of blind detection and the number of times of channel estimation processing may exceed the calculation processing capability of the user terminal.

In a Primary Cell (PCell), the following processing methods are being studied: when at least one of the number of blind detections and the number of channel estimation processes is equal to or greater than a specific value, the user terminal does not perform blind detection on a part of the PDCCHs according to a specific rule.

In a Secondary Cell (SCell), there is a possibility that a processing method such as PCell is not specified. In this case, the base station (e.g., the gNB) needs to set such that at least one of the number of blind detections by the user terminal and the number of channel estimation processes does not exceed a specific value.

Therefore, in the SCell, when the user terminal is configured to monitor a search space other than the search space for the response signal (BFRQR) to the beam recovery request, it is necessary to perform setting of the monitoring in consideration of the calculation processing capacity of the user terminal.

Therefore, the present inventors have specifically studied an appropriate setting in a case where a user terminal is configured to monitor a search space other than a search space for a response signal (BFRQR) to a beam recovery request in a beam recovery procedure of a future wireless communication system.

Hereinafter, the present embodiment will be described in detail with reference to the drawings.

(first mode)

In the first embodiment, in section 1, section 2, and section 3 of the beam recovery procedure of the future wireless communication system shown in fig. 1, the configuration of a search space (hereinafter, also referred to as "other search space") other than the search space for the response signal (BFRQR) to the beam recovery request is monitored by the user terminal and examined.

When the search space for the response signal (BFRQR) to the beam recovery request is set to the PCell, the user terminal may monitor a search space (other search space) other than the search space for the response signal (BFRQR) to the beam recovery request.

In this case, the user terminal may monitor the other search space as long as the other search space is a common search space or a paging search space.

With this configuration, by applying the processing method in PCell, it is possible to avoid the occurrence of a situation in which a part of PDCCHs is not blindly detected, and to detect important PDCCHs (dci) such as ETWS in a search space (other search space) other than a search space for a response signal (BFRQR) to a beam recovery request by a user terminal.

When the search space for the response signal (BFRQR) to the beam recovery request is set to the Primary and Secondary cells (pscells) or scells, the user terminal may not monitor (does not monitor, does not expect to monitor) the search space other than the search space for the response signal (BFRQR) to the beam recovery request.

The user terminal may apply the setting related to the monitoring when at least 1 of the following conditions (1) to (3) is satisfied. That is, when the following conditions (1) to (3) are not satisfied, the user terminal may not monitor a search space (other search space) other than the search space for the response signal (BFRQR) to the beam recovery request.

Condition (1) is that the search space for the response signal (BFRQR) to the beam recovery request has the same Subcarrier Spacing (SCS)) as the other search spaces.

Condition (2) is that the search space for the response signal (BFRQR) to the beam recovery request is in QCL type D relationship with other search spaces. This condition is related to an interval until a Random Access Response (RAR) is detected, particularly in a RAR window.

The condition (3) is that the other search space is a common search space (e.g., type 0A, or type 2). According to this condition, it is possible to detect paging DCI transmitted in a common search space.

Fig. 2 is a diagram showing a RAR window in initial access versus search space. In the random access for initial access, the user terminal may decode (decode) only at least one of the PDCCH and the PDSCH of QCL type D in a portion of the RAR window where the RAR search space overlaps the reference search space.

That is, the user terminal may decode the PDCCH and the PDSCH except for QCL type D in symbols except for a portion where the RAR search space overlaps the reference search space within the RAR window.

The reference search space means a type 0-PDCCH common search space, a type 0A-PDCCH common search space, a type 2-PDCCH common search space, or a type 3-PDCCH common search space.

According to the first aspect, it is possible to appropriately set a configuration of a search space for monitoring the user terminal, excluding a search space for a response signal (BFRQR) to the beam recovery request.

(second mode)

In the second embodiment, in the section 1 and the section 2 of the beam recovery procedure of the future wireless communication system shown in fig. 1, the configuration of the search space (other search space) other than the search space for the response signal (BFRQR) to the beam recovery request is monitored for the user terminal and examined.

When the search space for the response signal (BFRQR) to the beam recovery request is set to the PCell, the user terminal may monitor a search space other than the search space for the response signal (BFRQR) to the beam recovery request.

When the search space for the response signal (BFRQR) to the beam recovery request is set to the PSCell or SCell, the user terminal may not monitor (does not monitor, does not expect to monitor) the search space other than the search space for the response signal (BFRQR) to the beam recovery request.

The user terminal may apply the setting related to the monitoring when at least 1 of the following conditions (1) to (3) is satisfied. That is, when the following conditions (1) to (3) are not satisfied, the user terminal may not monitor a search space (other search space) other than the search space for the response signal (BFRQR) to the beam recovery request.

Condition (1) is that the search space for the response signal (BFRQR) to the beam recovery request has the same subcarrier spacing (SCS) as the other search spaces.

Condition (2) is that the search space for the response signal (BFRQR) to the beam recovery request is in QCL type D relationship with other search spaces. This condition is related to an interval until a Random Access Response (RAR) is detected, particularly in a RAR window.

The condition (3) is that the other search space is a common search space (e.g., type 0A, or type 2). According to this condition, it is possible to detect paging DCI transmitted in a common search space.

In the beam recovery procedure, in the section 3 after receiving or detecting the response signal (gNB response) to the beam recovery request (BFRQ), the user terminal may not monitor the search space as set in the sections 1 and 2.

After receiving the response signal (gNB response) to the beam recovery request (BFRQ), the base station recognizes that the base station can connect to the user terminal through the beam of the response signal, and therefore, may transmit an important PDCCH in the search space for the response signal (BFRQR) to the beam recovery request. Alternatively, the base station may transmit an important PDCCH in a search space corresponding to the OCL of QCL type D, which is a response signal to the beam recovery request (BFRQ).

In the section 3, the search space is not monitored as set in the sections 1 and 2, so that the reception process of the user terminal can be simplified and the power consumption of the user terminal can be reduced.

According to the second aspect, it is possible to appropriately set a configuration of a search space for monitoring the user terminal, excluding a search space for a response signal (BFRQR) to the beam recovery request.

(variants)

The user terminal may also report to the network whether multiple beams can be received simultaneously in the UE capability (capability).

It is also conceivable that a user terminal reporting that a plurality of beams can be received simultaneously monitors a search space for a response signal (BFRQR) to a beam recovery request and another search space regardless of whether the user terminal is DCL type D.

A user terminal that does not report the capability of UE to simultaneously receive multiple beams may be expected to perform the same operations as a user terminal that reports that it is not possible to simultaneously receive multiple beams.

Fig. 3 is a diagram illustrating a scenario assumed in a case where a user terminal is capable of simultaneously receiving a plurality of beams. It is envisaged that a user terminal capable of receiving multiple beams simultaneously supports digital beams as shown in figure 3A. Alternatively, it is assumed that a user terminal capable of simultaneously receiving a plurality of beams holds a plurality of panels as shown in fig. 3B.

In the beam recovery procedure, the response signal to the beam recovery request (BFRQ) may notify not only whether the Beam Failure Recovery (BFR) is completed or not but also the DL assignment (assignment) of the PDSCH used for TCI state setting of the PDCCH with 1 bit.

Similarly, the DL assignment of the PDSCH for setting the beam information of the PDSCH (TCI state) or the beam information of the PUCCH (spatial relationship information) may be notified.

The beam information (TCI status or spatial relationship information) is selected through DCI or MAC CE and updated through RRC. For example, since the MAC CE is included in the PDSCH, a DL assignment for assigning the PDSCH is notified.

In the beam recovery procedure, the response signal to the beam recovery request (BFRQ) may notify not only whether the Beam Failure Recovery (BFR) is completed but also the DL allocation for TCI state selection of the PDSCH with 1 bit. Meanwhile, the resource allocation of the PDSCH may also be performed.

The response signal to the beam recovery request (BFRQ) may also inform not only whether the Beam Failure Recovery (BFR) is completed with 1 bit but also contain an indication to initiate a beam report of Aperiodic CSI (a-CSI) report or Semi-persistent CSI (SP-CSI)) report in the beam recovery process.

By including such an indication, the user terminal can be caused to perform beam reporting simultaneously with completion of Beam Failure Recovery (BFR), and therefore the network can quickly select the best beam and notify the user terminal. That is, the time from the Beam Failure Recovery (BFR) to the optimum beam selection can be shortened.

(Wireless communication System)

The following describes the configuration of the radio communication system according to the present embodiment. The radio communication method according to the above-described embodiment is applied to this radio communication system.

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

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

User terminal 20 can connect to both base station 11 and base station 12. It is envisaged that the user terminal 20 simultaneously uses the macro cell C1 and the small cell C2 using different frequencies through Carrier Aggregation (CA) or Dual Connectivity (DC). The user terminal 20 can apply Carrier Aggregation (CA) or Dual Connectivity (DC) with a plurality of cells (CCs), e.g., 2 or more CCs. The user terminal can utilize the licensed band CC and the unlicensed band CC as a plurality of cells. A configuration can be made such that a TDD carrier to which the shortened TTI is applied is included in any of a plurality of cells.

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

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

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

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

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

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

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

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

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

< base station >

Fig. 5 is a diagram showing an example of the overall configuration of the base station according to the present embodiment. The base station 10 includes a plurality of transmission/reception antennas 101, an amplifier unit 102, a transmission/reception unit 103, a baseband signal processing unit 104, a call processing unit 105, and a transmission line interface 106. The number of the transmission/reception antennas 101, the amplifier unit 102, and the transmission/reception unit 103 may be 1 or more. The base station 10 may be a downlink data transmitting apparatus and an uplink data receiving apparatus.

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

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

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

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

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

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

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

Transmission/reception section 103 may transmit signals using a transmission beam or may receive signals using a reception beam. Transmission/reception section 103 may transmit and receive signals using a specific beam determined by control section 301.

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

Transmission/reception section 103 may receive the beam recovery request (BFRQ) during the beam recovery process and transmit a response signal (BFRQR) to the beam recovery request.

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

Fig. 6 is a diagram showing an example of a functional configuration of a base station according to the present embodiment. In the figure, the functional blocks mainly showing the characteristic parts in the present embodiment may be configured such that the base station 10 also has other functional blocks necessary for wireless communication. The baseband signal processing section 104 includes at least a control section 301, a transmission signal generation section 302, a mapping section 303, a reception signal processing section 304, and a measurement section 305.

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

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

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

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

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

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

The received signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, reception processing section 304 outputs at least 1 of the preamble, the control information, and the UL data to control section 301. Further, received signal processing section 304 outputs the received signal and the signal after the reception processing to measurement section 305.

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

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

< user terminal >

Fig. 7 is a diagram showing an example of the overall configuration of the user terminal according to the present embodiment. The user terminal 20 includes a plurality of transmission/reception antennas 201, an amplifier unit 202, a transmission/reception unit 203, a baseband signal processing unit 204, and an application unit 205. The number of the transmission/reception antenna 201, the amplifier unit 202, and the transmission/reception unit 203 may be 1 or more. The user terminal 20 may be a downlink data receiving apparatus and an uplink data transmitting apparatus.

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

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

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

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

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

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

Transmission/reception section 203 may transmit a beam recovery request (BFRQ) and receive a response signal (BFRQR) to the beam recovery request during the beam recovery process.

Transmission/reception section 203 may monitor at least one of the search spaces (first search space) for the response signal (BFRQR) to the beam recovery request and the other search spaces (second search space) based on monitoring settings relating to these search spaces.

Fig. 8 is a diagram showing an example of a functional configuration of a user terminal according to the present embodiment. In the figure, the functional blocks mainly showing the characteristic parts in the present embodiment are assumed to be the functional blocks necessary for the user terminal 20 to also have wireless communication. The baseband signal processing section 204 included in the user terminal 20 includes at least a control section 401, a transmission signal generation section 402, a mapping section 403, a reception signal processing section 404, and a measurement section 405.

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

Control section 401 controls, for example, generation of a signal by transmission signal generation section 402, allocation of a signal by mapping section 403, and the like. Further, the control unit 401 controls reception processing of signals by the reception signal processing unit 404, measurement of signals by the measurement unit 405, and the like.

Control section 401 may control the monitor setting regarding the search space (first search space) for the response signal (BFRQR) to the beam recovery request and the other search space (second search space) based on the carrier (PCell, PSCell, or SCell) for which the search space (first search space) for the response signal (BFRQR) to the beam recovery request is set.

Control section 401 may control the monitor setting regarding the search space on the condition that the search space (first search space) for the response signal (BFRQR) to the beam recovery request and the other search space (second search space) have the same subcarrier spacing (SCS).

Control section 401 may control the monitor setting regarding the search space on the condition that the search space (first search space) for the response signal (BFRQR) to the beam recovery request and the other search space (second search space) are QCL type D.

The control unit 401 may control the monitoring setting regarding the search space on the condition that whether or not the other search space (second search space) is the common search space.

Control section 401 may control the monitoring setting relating to the search space so that the monitoring setting relating to the search space in the previous section is no longer based on the detection of the response signal (BFRQR) to the beam recovery request.

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

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

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

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

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

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

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

Measurement unit 405 may also measure, for example, received power (e.g., RSRP), DL received quality (e.g., RSRQ), channel status, etc. of the received signal. The measurement result may also be output to the control unit 401.

(hardware construction)

The block diagrams used in the description of the above embodiments show blocks in functional units. These functional blocks (constituent units) are realized by any combination of at least one of hardware and software. The method of implementing each functional block is not particularly limited. That is, each functional block may be implemented by 1 apparatus physically or logically combined, or by a plurality of apparatuses connected directly or indirectly (for example, by wire or wireless) to 2 or more apparatuses physically or logically separated. The functional blocks may also be implemented by combining software with the above-described 1 device or the above-described devices.

Here, the functions are: determination, decision, determination, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, establishment, comparison, assumption, expectation, view, broadcast (broadcasting), notification (notification), communication (communicating), forwarding (forwarding), composition (setting), reconfiguration (resetting), allocation (allocating, mapping), assignment (assigning), and the like, but is not limited thereto. For example, a functional block (a constituent unit) that functions as transmission may be referred to as a transmission unit (transmitting unit), a transmitter (transmitter), or the like. Any of the above-described methods for realizing the above is not particularly limited.

For example, the base station, the user terminal, and the like according to one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 9 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment. The base station 10 and the user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the present disclosure, words of a device, a circuit, an apparatus, a section (section), a unit, and the like can be mutually replaced. The hardware configuration of the base station 10 and the user terminal 20 may include 1 or more of each illustrated device, or may be configured as a device that does not include a part of each illustrated device.

For example, the processor 1001 is only illustrated as 1, but a plurality of processors may be provided. The processing may be executed by 1 processor, or may be executed by 2 or more processors simultaneously, sequentially, or by another method. Processor 1001 may also be implemented by more than 1 chip.

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

The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be configured by a Central Processing Unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, a register, and the like. For example, the baseband signal processing unit 104(204), the call processing unit 105, and the like can be implemented by the processor 1001.

The processor 1001 reads 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 in accordance with these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiments is used. For example, the control unit 401 of the user terminal 20 may be realized by a control program stored in the memory 1002 and operated by the processor 1001, and may be similarly realized for other functional blocks.

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

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

The communication device 1004 is hardware (transmission/reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, a network controller, a network card, a communication module, or the like, for example. Communication device 1004 may be configured to include a high-Frequency switch, a duplexer, a filter, a Frequency synthesizer, and the like, in order to realize at least one of Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD), for example. For example, the transmission/reception antennas 101 and 201, the amplifier units 102 and 202, the transmission/reception units 103 and 203, the transmission line interface 106, and the like described above may be realized by the communication device 1004. The transmission/reception section 103(203) may be physically or logically separated from the transmission section 103a (203a) and the reception section 103b (203 b).

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

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

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

(modification example)

Terms described in the present disclosure and/or terms required for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, channels, symbols, and signals (symbols or signaling) may be substituted for one another. The signal may also be a message. The reference signal may also be referred to as rs (reference signal) for short, and may also be referred to as Pilot (Pilot), Pilot signal, or the like, depending on the applied standard. Component Carriers (CCs) may also be referred to as cells, frequency carriers, Carrier frequencies, and the like.

The radio frame may be formed of 1 or more periods (frames) in the time domain. Each of the 1 or more periods (frames) constituting a radio frame may also be referred to as a subframe. Further, the subframe may be formed of 1 or more slots in the time domain. The subframe may also be a fixed duration (e.g., 1ms) that is not dependent on a parameter set (numerology).

Here, the parameter set may also refer to a communication parameter applied to at least one of transmission and reception of a certain signal or channel. For example, the number of symbols per TTI may be at least 1 of Subcarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, specific filtering performed by the transceiver in the frequency domain, and specific windowing performed by the transceiver in the Time domain.

The slot is formed of 1 or more symbols in the time domain, for example, Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiplexing (SC-FDMA) symbols, or the like). In addition, the time slot may be a time unit based on a parameter set.

A slot may also contain multiple mini slots (mini slots). Each mini-slot may also be made up of 1 or more symbols in the time domain. The mini-slots may also be referred to as subslots. A mini-slot may also be made up of a smaller number of symbols than a slot. PDSCH (or PUSCH) transmitted in a larger time unit than mini-slot may also be referred to as PDSCH (PUSCH) mapping type a. PDSCH (or PUSCH) transmitted with mini-slots may also be referred to as PDSCH (PUSCH) mapping type B.

Any one of a radio frame, a subframe, a slot, a mini-slot, and a symbol represents a unit of time when a signal is transmitted. The radio frame, subframe, slot, mini-slot and symbol may be referred to as a symbol. .

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

Here, the TTI refers to, for example, the smallest 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 usable by each user terminal) to each user terminal in TTI units. The definition of TTI is not limited thereto.

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

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

A TTI having a duration of 1ms may also be referred to as a normal TTI (TTI in LTE rel.8-12), a standard TTI, a long TTI, a normal subframe, a standard subframe, a long subframe, a slot, etc. A TTI shorter than a normal TTI may also be referred to as a shortened TTI, a short TTI, a partial TTI, a shortened subframe, a short subframe, a mini-slot, a sub-slot, a slot, etc.

Long TTIs (e.g., normal TTIs, sub-frames, etc.) may also be replaced by TTIs having a duration of more than 1ms, and short TTIs (e.g., shortened TTIs, etc.) may also be replaced by TTIs having a TTI length less than the long TTI and greater than 1 ms.

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

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

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

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

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

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

In the present disclosure, the names used for parameters and the like are not limitative names in all aspects. Further, the mathematical expressions and the like using these parameters may also be different from those explicitly disclosed in the present disclosure. Various channels, such as a Physical Uplink Control Channel (PUCCH), a Physical Downlink Control Channel (PDCCH), and information elements, can be identified by any appropriate name, and thus, various names assigned to these various channels and information elements are not limitative names in all aspects.

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

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

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

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

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

The notification of the specific information (for example, the notification of "yes X") is not limited to the explicit notification, and may be performed implicitly (for example, by not notifying the specific information or by notifying another information).

The determination may be made based on a value (whether 0 or 1) represented by 1 bit, may be made based on a true-false value (boolean value) represented by true (true) or false (false), or may be made by comparison of values (for example, comparison with a specific value).

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

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

The terms "system" and "network" as used in this disclosure can be used interchangeably.

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

In the present disclosure, terms such as "Base Station (BS)", "wireless Base Station", "fixed Station (fixed Station)", "NodeB", "enodeb (enb)", "gbnodeb (gnb)", "access point (access point)", "transmission point)", "reception point", "transmission/reception point", "panel", "cell", "sector group", "carrier", "component carrier", "Bandwidth Part (BWP)", and the like can be used interchangeably. In some cases, a base station is also referred to by terms such as macrocell, smallcell, femtocell, picocell, and the like.

A base station can accommodate 1 or more (e.g., 3) cells (also referred to as sectors). In the case where a base station accommodates a plurality of cells, the entire coverage area of the base station can be divided into a plurality of smaller areas, and each smaller area can also provide a communication service through a base station subsystem (e.g., an indoor small base station (Remote Radio Head (RRH))) — the term "cell" or "sector" refers to a part or the whole of the coverage area of at least one of the base station and the base station subsystem that performs a communication service within the coverage area.

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

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

At least one of the base station and the mobile station may also be referred to as a transmitting apparatus, a receiving apparatus, a communication apparatus, or the like. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, or the like. The moving body may be a vehicle (e.g., a vehicle, an airplane, etc.), may be a moving body that moves in an unmanned state (e.g., an unmanned aerial vehicle, an autonomous vehicle, etc.), or may be a robot (manned or unmanned). At least one of the base station and the mobile station includes a device that does not necessarily move during a communication operation. For example, at least one of the base station and the mobile station may be an iot (internet of things) device such as a sensor.

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

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

In the present disclosure, it is assumed that the operation performed by the base station may be performed by an upper node (upper node) in some cases. It is obvious that in a network including 1 or more network nodes (network nodes) having a base station, various operations performed for communication with a terminal may be performed by the base station, 1 or more network nodes other than the base station (for example, an MME (Mobility Management Entity), an S-GW (Serving-Gateway), and the like are considered, but not limited thereto), or a combination of these.

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

The aspects/embodiments described in the present disclosure may also be applied to systems using LTE (Long Term Evolution), LTE-a (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (fourth generation Mobile communication System), 5G (fifth generation Mobile communication System), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New Radio Access), FX (Future Radio Access), GSM (GSM registration System (Global System for Mobile communication), CDMA (Radio Broadband), and CDMA (CDMA 2000) SUPER Mobile communication System (Global System for Mobile communication)) IEEE 802.11(Wi-Fi (registered trademark)), IEEE 802.16(WiMAX (registered trademark)), IEEE802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), a system using another appropriate wireless communication method, a next generation system expanded based on these, and the like. In addition, a plurality of systems may also be applied in combination (e.g., LTE or LTE-a, combination with 5G, or the like).

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

Any reference to a named element using "first," "second," etc. as used in this disclosure does not comprehensively define the amount or order of such elements. These designations may also be used in this disclosure as a convenient way to distinguish between more than 2 elements. Thus, reference to first and second elements does not imply that only 2 elements may be used or that the first element must somehow override the second element.

The term "determining" as used in this disclosure encompasses a wide variety of actions in some cases. For example, "determination (decision)" may be considered as a case where "determination (decision)" is performed on determination (rounding), calculation (calculating), processing (processing), derivation (deriving), investigation (investigating), search (looking up), search (inquiry), query (inquiry)) (for example, search in a table, a database, or another data structure), confirmation (intercepting), and the like.

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

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

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

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

The terms "connected" and "coupled" or all variations thereof used in the present disclosure mean that 2 or more elements are directly or indirectly connected or coupled to each other, and may include a case where 1 or more intermediate elements are present between 2 elements that are "connected" or "coupled" to each other. The combination or connection between the elements may be physical, logical, or a combination of these. For example, "connect" may also be replaced with "access".

In the present disclosure, where 2 elements are connected, it can be considered that more than 1 wire, cable, printed electrical connection, etc., and as a few non-limiting and non-inclusive examples, are "connected" or "joined" to each other with electromagnetic energy having a wavelength in the radio frequency domain, the microwave region, the light (both visible and invisible) region, etc.

In the present disclosure, the term "a is different from B" may also mean "a is different from B". The terms "separate", "coupled", etc. may be construed similarly.

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

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

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