Terminal, base station, and measurement method

Abstract

This technology provides a mechanism that enables terminals in wireless communication systems to properly perform fault detection and recovery. [Solution] The terminal comprises a receiving unit that receives downlink control information from a base station, and a control unit that performs measurements for radio link monitoring or beam fault recovery based on the format of the downlink control information and a non-periodic reference signal received from the base station.

Description

Technical Field

[0001] The present invention relates to a terminal, a base station, and a measurement method in a wireless communication system.

Background Art

[0002] In NR (New Radio), which is a successor system to LTE (Long Term Evolution) (also referred to as "5G"), technologies that meet requirements such as a large-capacity system, high data transmission speed, low latency, simultaneous connection of a large number of terminals, low cost, and power saving are being studied (for example, Non-Patent Document 1). In addition, in NR, utilization of high-frequency bands such as 52.6 to 114.25 GHz is being studied.

[0003] In the NR system, in order to expand the frequency band, utilization of a frequency band licensed to a communications carrier (operator) (a frequency band different from the licensed band (unlicensed band, unlicensed carrier, unlicensed CC)) is supported.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

[0005] NR specifies various functions for detecting and recovering from wireless link failures (e.g., Non-Patent Documents 2-5). Furthermore, NR also specifies various functions for detecting and recovering from beam failures (e.g., Non-Patent Documents 2-5).

[0006] However, terminals conforming to existing NR regulations, which are designed for frequency bands up to 52.6 GHz, may not be able to properly perform wireless link / beam fault detection and recovery in high-frequency bands such as 52.6-114.25 GHz, where the use of unlicensed bands is anticipated.

[0007] This invention has been made in view of the above points, and aims to provide a technology that enables a terminal in a wireless communication system to properly perform fault detection and recovery. [Means for solving the problem]

[0008] According to the disclosed technology, a receiving unit receives downlink control information from a base station, Based on the format of the downlink control information, a control unit performs measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal received from the base station. A terminal equipped with this feature is provided. [Effects of the Invention]

[0009] According to the disclosed technology, a technology is provided that enables a terminal in a wireless communication system to properly perform fault detection and recovery. [Brief explanation of the drawing]

[0010] [Figure 1]This is a diagram for explaining the wireless communication system in the embodiment of the present invention. [Figure 2] This is a diagram for explaining the wireless communication system in the embodiment of the present invention. [Figure 3] This is a diagram showing an example of a band. [Figure 4] This is a diagram showing the relationship between SCS and symbol length. [Figure 5] This is a diagram showing an example of the basic procedure in the embodiment of the present invention. [Figure 6] This is a diagram showing an example of the RLM / RLF procedure. [Figure 7] This is a diagram for explaining Rel-15 BFR. [Figure 8] This is a diagram for explaining Rel-16 BFR. [Figure 9] This is a diagram showing an example of the specification for RLM / BFD. [Figure 10] This is a diagram showing an example of the specification for BFR. [Figure 11] This is a diagram for explaining the transmission status of CSI-RS / SSB when performing LBT. [Figure 12] This is a diagram showing an example of the R-16 Aperiodic CSI report triggering procedure. [Figure 13] This is a diagram showing an example of the specification. [Figure 14] This is a diagram showing an example of the specification in Example 3. [Figure 15] This is a diagram showing an example of the specification in Example 3. [Figure 16] This is a diagram showing an example of the specification in Example 3. [Figure 17] This is a diagram showing an example of the setting information in Example 3. [Figure 18] This is a diagram showing an example of the setting information in Example 3. [Figure 19] This is a diagram showing an example of the specification in Example 3. [Figure 20] This is a diagram showing an example of the specification in Example 3. [Figure 21] This figure shows an example of a specification document in Example 4. [Figure 22] This figure shows an example of the functional configuration of the base station 10 in an embodiment of the present invention. [Figure 23] This figure shows an example of the functional configuration of terminal 20 in an embodiment of the present invention. [Figure 24] This figure shows an example of the hardware configuration of a base station 10 or terminal 20 in an embodiment of the present invention. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below with reference to the drawings. Note that the embodiments described below are examples, and the embodiments to which the present invention is applied are not limited to those described below.

[0012] In the operation of the wireless communication system according to the embodiment of the present invention, existing technologies are used as appropriate. Such existing technologies include, for example, existing NR (New Radio). The wireless communication system in this embodiment (base station 10 and terminal 20) basically operates in accordance with existing regulations (e.g., Non-Patent Documents 1-5). However, in order to solve the problems that arise when considering the use of high frequency bands or unlicensed bands, the base station 10 and terminal 20 also perform operations that are not included in the existing regulations. The description of the embodiments described later mainly describes operations that are not included in the existing regulations. Note that the numerical values ​​described below are all examples.

[0013] Furthermore, in the embodiments of the present invention, the duplex method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or any other method (for example, a Flexible Duplex).

[0014] Furthermore, in the embodiments of the present invention, "configuring" wireless parameters may mean that predetermined values ​​are pre-configured, or that wireless parameters notified from the base station 10 or terminal 20 are configured.

[0015] In the embodiments described later, Apriodic CSI-RS is given as an example of the reference signal used for RLM / BFR, but the non-periodic reference signal to which the technology of the present invention can be applied is not limited to Apriodic CSI-RS. For example, a non-periodic synchronization signal may be used as the non-periodic reference signal to which the technology of the present invention can be applied, or a reference signal other than SCI-RS may be used.

[0016] (System Configuration)

[0017] Figure 1 is a diagram illustrating a wireless communication system in an embodiment of the present invention. The wireless communication system in the embodiment of the present invention includes a base station 10 and a terminal 20, as shown in Figure 1. Although Figure 1 shows one base station 10 and one terminal 20, this is an example, and there may be multiple base stations 10 and terminals 20.

[0018] Base station 10 is a communication device that provides one or more cells and performs wireless communication with terminal 20. The physical resources of the wireless signal are defined in the time domain and the frequency domain.

[0019] OFDM is used as the wireless access method. In the frequency domain, subcarrier spacing (SCS) of at least 15kHz, 30kHz, 120kHz, and 240kHz are supported. In addition, regardless of the SCS, a resource block is composed of a predetermined number (e.g., 12) consecutive subcarriers.

[0020] When terminal 20 performs initial access, it detects the SSB (SS / PBCH block) and identifies the SCS in the PDCCH and PDSCH based on the PBCH contained in the SSB.

[0021] Furthermore, in the time domain, a slot is composed of multiple OFDM symbols (for example, 14 symbols regardless of the subcarrier interval). Hereafter, OFDM symbols will be referred to as "symbols." A slot is a scheduling unit. In addition, a subframe of 1ms interval is defined, and a frame consisting of 10 subframes is defined. Note that the number of symbols per slot is not limited to 14.

[0022] As shown in Figure 1, base station 10 transmits control information or data to terminal 20 via DL (Downlink) and receives control information or data from terminal 20 via UL (Uplink). Both base station 10 and terminal 20 are capable of transmitting and receiving signals using beamforming. Furthermore, both base station 10 and terminal 20 are capable of applying MIMO (Multiple Input Multiple Output) communication to DL or UL. In addition, both base station 10 and terminal 20 may communicate via SCell (Secondary Cell) and PCell (Primary Cell) using CA (Carrier Aggregation).

[0023] Terminal 20 is a communication device equipped with wireless communication capabilities, such as a smartphone, mobile phone, tablet, wearable device, or M2M (Machine-to-Machine) communication module. As shown in Figure 1, Terminal 20 receives control information or data from the base station 10 via DL and transmits control information or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system.

[0024] Terminal 20 is capable of carrier aggregation, which involves bundling multiple cells (multiple CCs (component carriers)) to communicate with base station 10. Carrier aggregation uses one PCell (primary cell) and one or more SCells (secondary cells). A PUCCH-SCell with a PUCCH may also be used.

[0025] Figure 2 shows an example of a wireless communication system configuration when NR-DC (NR-Dual connectivity) is implemented. As shown in Figure 2, the system is equipped with a base station 10A acting as the Master Node (MN) and a base station 10B acting as the Secondary Node (SN). Base stations 10A and 10B are each connected to the core network. Terminal 20 communicates with both base stations 10A and 10B.

[0026] A cell group provided by base station 10A, which is an MN (Mobile Network Unit), is called an MCG (Master Cell Group), and a cell group provided by base station 10B, which is an SN (Stationary Network Unit), is called an SCG (Secondary Cell Group). In a DC (Data Center), an MCG consists of one PCell and one or more SCells, and an SCG consists of one PSCell (Primary SCell) and one or more SCells. In this specification, CC (Component Carrier) and cell may be used synonymously. Also, PCell and PSCell may be referred to as SPCell.

[0027] In the wireless communication system of this embodiment, when using an unlicensed band, LBT (Listen Before Talk) is performed. The base station 10 or terminal 20 senses the signal and transmits if the sensing result is idle, and refrains from transmitting if the sensing result is busy. Note that LBT is not always performed in the unlicensed band, and there may be cases where LBT is not performed in the unlicensed band.

[0028] (Regarding frequency bands) Figure 3 shows examples of frequency bands used in existing NR and frequency bands used in the wireless communication system according to this embodiment. There are two frequency bands (which may also be called frequency ranges) in existing NR: FR1 (0.41 GHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz). As shown in Figure 3, FR1 supports 15 kHz, 30 kHz, and 60 kHz as SCS frequencies and a bandwidth (BW) of 5 to 100 MHz. FR2 supports 60 kHz, 120 kHz, and 240 kHz (SSB only) as SCS frequencies and a bandwidth (BW) of 50 to 400 MHz.

[0029] The wireless communication system according to this embodiment is intended to utilize a frequency band higher than 52.6 GHz (for example, 52.6 GHz to 114.25 GHz) that is not used in existing NR systems. This frequency band may also be referred to as FR4.

[0030] Furthermore, in this embodiment, as the frequency band is expanded as described above, it is assumed that a wider SCS than existing SCSs will be used. For example, a 480kHz or wider SCS will be used as the SCS for SSB and PDCCH / PDSCH.

[0031] In the high-frequency band, it is anticipated that multiple narrow beams will be used to compensate for the large propagation losses. In addition, wider SCSs (e.g., 480 kHz, 960 kHz) will be used than the existing FR2 SCSs.

[0032] Figure 4 shows the relationship between SCS and symbol length (symbol duration). As shown in Figure 4, as the SCS widens, the symbol length (symbol duration) decreases. Also, assuming that the number of symbols per slot remains constant (i.e., 14 symbols), as the SCS widens, the slot length decreases.

[0033] Thus, when the beams become narrower and more numerous, and the SCS becomes wider, if the terminal 20 and base station 10 operate according to conventional specifications, it may not be possible to properly detect and recover from radio link / beam failures. For example, as will be described later, frequent LBT failures are anticipated, in which case it may not be possible to properly measure the reference signal for radio link / beam failure detection and recovery.

[0034] The following describes the technologies that enable terminal 20 and base station 10 to properly detect and recover from wireless link / beam failures.

[0035] (Basic operation) First, a basic example of operation in the wireless communication system of this embodiment will be explained with reference to Figure 5. In this embodiment, Aperiodic CSI-RS is used, in which transmission from the base station 10 and reception (and measurement) at the terminal 20 are performed by DCI trigger. Therefore, a basic example of operation related to Aperiodic CSI-RS will be explained first.

[0036] In S100, terminal 20 transmits capability information (UE capability) to base station 10. Based on this capability information, base station 10 can determine, for example, the information to transmit to terminal 20 in S101 and S102 below.

[0037] In S101, the base station 10 sends configuration information to the terminal 20 via an RRC message, and the terminal 20 receives the configuration information. This configuration information is, for example, configuration information related to Aperiodic CSI-RS, as described later.

[0038] In S102, the base station 10 transmits a trigger to the terminal 20 via DCI, and the terminal 20 receives the trigger. This trigger is, for example, a trigger for the terminal 10 to perform an Aperiodic CSI-RS measurement for RLM / BFR, as described later. In this embodiment, "A / B" means A or B, or both A and B. Also, "BFR" means "BFD / New Beam Selection".

[0039] Upon receiving DCI, after a specified time, in S103, terminal 20 receives Aperiodic CSI-RS, and in S104, performs measurements for purposes such as wireless link / beam fault detection and recovery.

[0040] As examples of operations using CSI-RS, RLM / RLF and BFR will be explained. Here, operations based on existing technologies disclosed in Non-Patent Documents 1-5, etc., will be described.

[0041] (RLM / RLF) First, let's explain RLM / RLF. Terminal 20 (and base station 10) performs RLM (Radio Link Monitoring), and when it detects RLF (Radio Link Failure), it performs actions such as RRC connection re-establishment.

[0042] In RLM, counter values ​​N310 and N311, which are threshold values ​​for the number of cycles, and timers T310 and T311 are used. These parameters are received by terminal 20 from base station 10 via RRC signaling.

[0043] N310 is the threshold for the number of consecutive out-of-sync indications. When the number of consecutive out-of-sync indications reaches N310, the timer T310 is started.

[0044] T310 is started by the trigger described above and stops after N311 consecutive in-sync indications are received. When T310 expires, for example, an RRC connection re-establishment is performed. T311 is started at the beginning of the RRC connection re-establishment procedure during cell re-selection and stops when cell re-selection is successful. When T311 expires, terminal 20 enters an RRC idle state.

[0045] An example of the RLM procedure in terminal 20 will be explained with reference to Figure 6. In terminal 20, when a lower layer (e.g., the functional unit of the physical layer) detects out-of-sync (degradation of wireless link quality), it notifies the upper layer (e.g., the functional unit of the RRC) of the out-of-sync indication.

[0046] Terminal 20 starts Timer T310 when it detects that N310 consecutive out-of-sync indications have been notified from a lower layer to a higher layer. Terminal 20 stops Timer T310 when it detects that N311 consecutive in-sync indications (wireless link normal notification) have been notified from a lower layer to a higher layer while Timer T310 is running. If Timer T310 expires, Terminal 20 determines that an RLF has occurred and executes the RRC connection re-establishment procedure.

[0047] The above in-sync indication is information that can be defined, for example, as follows:

[0048] "Upon request from higher layers, the UE provides to higher layers the periodic CSI-RS configuration indexes and / or SS / PBCH block indexes from the set q1~ and the corresponding radio link quality measurements that are larger than or equal to Qin" In other words, in-sync indication is based on a certain threshold Q. in The above wireless quality measurement values ​​are the P-CSI-RS index, or (or both), the SS / PBCH block index (hereinafter sometimes referred to as SSB). The P-CSI-RS index and SSB index in question are within the set "q1~". q1~ are parameters notified from base station 10 to terminal 20 via RRC signaling, for example, by candidateBeamRSList for wireless link quality measurement. Note that wireless link quality may be RSRP or RSRQ.

[0049] The above out-of-sync indication is defined, for example, as follows:

[0050] "PHY in the UE provides an indication to higher layers when the radio link quality for all corresponding resource configurations in the set q0~ that the UE uses to assess the radio link quality is worse than the threshold Qout" In other words, out-of-sync indication is a threshold Q at which the wireless link quality of all resources in the set "q0~" that terminal 20 uses for wireless link quality evaluation is determined.out This is information that is notified in cases worse than the specified condition. q0~ is a set of P-CSI-RS indices that are notified from base station 10 to terminal 20 via RRC signaling, for example, by failureDetectionResources.

[0051] (BFD / BFR) Next, we will explain BFD / BFR. Here, we will describe the technology for detecting beam failures (BFD) and performing beam recovery (BFR). First, we will explain a basic example of operation in BFD / BFR of this embodiment with reference to Figures 7 and 8.

[0052] First, referring to Figure 7, we will explain an example of BFD / BFR operation in PCell / PSCell (BFR of R-15).

[0053] In S10, terminal 20 receives a reference signal (CSI-RS, SSB, or both CSI-RS and SSB) transmitted from base station 10 for each beam and measures its quality (RSRP, RSRQ, etc.). If terminal 20 determines that the quality of all reference signals (i.e., beams) has deteriorated a predetermined number of times, it performs the search for a new beam in S11.

[0054] In S10, all reference signals refer to a set of reference signals (or their indices) set from base station 10 to terminal 20 for beam failure detection (failure detection resources), and this is called q0. For example, 8 is set for this.

[0055] In S11, terminal 20 measures the L1-RSRP of candidate reference signals (candidateBeamRSList, set by base station 10 and called q1) and selects the reference signal (beam) with the maximum L1-RSRP as the new beam.

[0056] In S12, terminal 12 transmits a PRACH (preamble) at the PRACH occasion corresponding to the selected new beam. Terminal 20 monitors the BFR response (PDCCH) in the BFR response window that starts 4 slots later.

[0057] Terminal 20, 28 symbols after receiving the BFR response (PDCCH) in S13, monitors the PDCCH in CORESET#0, assuming that the PDCCH monitored in CORESET#0 is in a QCL relationship with the new beam (reference signal).

[0058] Next, with reference to Figure 8, we will explain an example of BFD / BFR operation for SCell (BFR introduced in R-16). In Figure 8, we assume that SCell is provided by base station 30.

[0059] In S21, terminal 20 receives a reference signal (CSI-RS, SSB, or both CSI-RS and SSB) transmitted from base station 30 for each beam and measures its quality (RSRP, RSRQ, etc.). If terminal 20 determines that the quality of all reference signals (i.e., beams) has deteriorated, it sends an SR (Scheduled Request) in S21 when the number of times it has determined that the quality of all reference signals (i.e., beams) has deteriorated reaches a predetermined threshold, it also performs a search for a new beam in S23.

[0060] In S20, all reference signals refer to a set of reference signals (or their indices) set from base station 10 to terminal 20 for beam failure detection (failure detection resources), and this is called q0. For example, 8 is set for this.

[0061] In S23, terminal 20 measures the L1-RSRP of candidate reference signals (candidateBeamRSList, set by base station 10 and called q1) and selects the reference signal (beam) with the maximum L1-RSRP as the new beam.

[0062] In S22, terminal 20 receives a UL grant and uses the allocated resources to send a MAC CE in S24. The MAC CE includes the index of the CC where the beam failure occurred and the index of the new reference signal for each CC (i.e., the beam index). Terminal 20 receives a BFR response (PDCCH) in S25.

[0063] Terminal 20 monitors PDCCHs 28 symbols after receiving the PDCCH that schedules PUSCH (PDCCH of S25), assuming that subsequent PDCCHs monitored by SCell are in a QCL relationship with the new beam (reference signal). Furthermore, after the aforementioned 28 symbols, Terminal 20 transmits subsequent PUSCHs using SCell with a spatial domain filter corresponding to the spatial domain filter of the new beam (reference signal). In other words, it also updates the QCL for PUSCHs.

[0064] (Regarding setting information for reference signals, etc.) Figure 9 shows an example of configuration information for RLM / BFD (Non-Patent Literature 2). As shown in Figure 9, RadioLinkMonitoringRS allows you to configure the purpose and resources of the reference signal. Figure 10 shows an example of configuration information for BFR (Non-Patent Literature 2). (Regarding the use of aperiodic reference signals) Since the 52.6 to 71 GHz frequency band intended for use in the wireless communication system of this embodiment includes the unlicensed spectrum (unlicensed band), LBT may be required in the wireless communication system of this embodiment.

[0065] In the RLM and BFR based on the existing technologies described above, the terminal 20 receives a reference signal (CSI-RS, SSB, or CSI-RS and SSB) periodically transmitted from the base station 10 and measures the quality.

[0066] However, when LBT is performed at base station 10, as shown in Figure 11, for example, LBT may succeed or fail at each transmission timing of the reference signal. As a result, it may become impossible to periodically transmit the reference signal from base station 10, and it is expected that the frequency at which terminal 20 can receive the reference signal will decrease. Therefore, RLM and BFR may not be able to be performed properly.

[0067] To address the above issues, terminal 20 uses a non-periodic reference signal based on a DCI trigger, rather than a periodic reference signal, as the reference signal used for beam monitoring / selection in RLM or BFR. An example of a non-periodic reference signal is Aperiodic CSI-RS.

[0068] For example, when terminal 20 and base station 10 use an unlicensed band (or perform LBT), base station 10 transmits a reference signal when LBT is successful.

[0069] Terminal 20 performs RLM and BFR by measuring a reference signal received aperiodically based on a trigger, and by performing counting processes as described in Figures 6, 7, and 8, etc. This allows RLM and BFR to be properly executed without being affected by LBT failure when LBT is required. The technology according to the present invention is also applicable even when LBT is not assumed.

[0070] (Regarding Aperiodic CSI report triggering) Here, the configuration information for Aperiodic CSI report triggering based on existing technologies (non-patent documents 2, 5, etc.) will be explained with reference to Figure 12.

[0071] To implement aperiodic CSI report triggering, first, the CSI-AperiodicTriggerStateList is set in RRC from base station 10 to terminal 20. The CSI-AperiodicTriggerStateList contains one or more indexed CSI-AperiodicTriggerStates.

[0072] Subsequently, the CSI request field of the DCI transmitted from base station 10 to terminal 20 specifies one CSI-AperiodicTriggerState from the CSI-AperiodicTriggerStateList. Note that the number of bits in the CSI request field (N TS If the length of the specified CSI-AperiodicTriggerStates is shorter than the length of all the configured CSI-AperiodicTriggerStates, MAC CE will also be used.

[0073] A single CSI-AperiodicTriggerState is associated with one or more Report settings, and each Report setting is associated with one or more Resource settings. A single Resource setting contains one or more CSI-RS resource sets. A single CSI-RS resource set contains one or more CSI-RS resources. In other words, terminal 20 can receive CSI-RS signals using one or more CSI-RS resources associated with the CSI-AperiodicTriggerState specified by the CSI request field.

[0074] Figure 13 shows an example of a CSI-AperiodicTriggerStateList (Non-Patent Literature 2). As shown in Figure 13, a CSI-AperiodicTriggerStateList contains one or more CSI-AperiodicTriggerStates, and a CSI-AperiodicTriggerState contains one or more resourceSets. The resourceSet represents an NZP-CSI-RS-ResourceSet for channel measurement.

[0075] (Regarding the detailed issues) In order to properly execute RLM / BFR even in situations where LBT failures occur, when applying Aperiodic CSI-RS to RLM / BFR, the challenges are whether or not to apply Periodic CSI-RS / SSB to RLM / BFR, and how to trigger Aperiodic CSI-RS to RLM / BFR.

[0076] In other words, if the existing Aperiodic CSI report triggering is applied as is, the triggered CSI-RS will be used for either CSI / beam reporting or tracking, depending on the ReportQuantity. Therefore, in order to support Aperiodic CSI-RS for RLM / BFR, it is necessary to notify terminal 20 of the purpose for which the triggered Aperiodic CSI-RS will be used (CSI / beam reporting, tracking, or RLM / BFR).

[0077] To this end, this embodiment proposes an extension of the trigger DCI and an extension of the RRC settings. Details will be described later.

[0078] Furthermore, while Alt1 and Alt2 below are possible methods for supporting Aperiodic CSI-RS triggering for RLM / BFR, in this embodiment, Alt1 is adopted considering the impact on the specification.

[0079] Alt1: Reuse and extend the R-16 Aperiodic CSI report triggering procedure as a baseline.

[0080] Design a new procedure to support Aperiodic CSI-RS triggering for Atl2:RLM / BFR.

[0081] The following describes specific examples of this embodiment, specifically Examples 1 to 4 and modified examples. Any or all of Examples 1 to 4 can be combined and implemented.

[0082] (Example 1) Example 1 is an example that examines whether to use only Aperiodic CSI-RS or to use both Aperiodic CSI-RS and Periodic CSI-RS for RLM / BFR measurements. Examples 1-1, 1-2, and 1-3 are described below.

[0083] <Example 1-1> In Example 1-1, only the Aperiodic CSI-RS is used for measurements in RLM / BFR. In this case, there are two variations, Alt1 and Alt2, for the selection of the beam applied to the Aperiodic CSI-RS.

[0084] Alt1: The Aperiodic CSI-RS beam used shall be the same as the beam set in CORESET.

[0085] In this case, for example, the base station 10 sets information indicating the same beam as the one set in CORESET to the terminal 20 as setting information regarding the Aperiodic CSI-RS beam (e.g., TCI state).

[0086] Alt2: No restrictions are placed on the Aperiodic CSI-RS beam used.

[0087] <Examples 1-2> In Examples 1-2, both Aperiodic CSI-RS and Periodic CSI-RS / SSB can be used for RLM / BFR. In other words, existing Periodic CSI-RS / SSB can be used for RLM / BFR in addition to existing applications such as CSI / beam reporting, and furthermore, Aperiodic CSI-RS can also be used for RLM / BFR.

[0088] The following Alt1 and Alt2 variations exist for selecting the beam to be applied to the Aperiodic CSI-RS in Example 1-2.

[0089] Alt1: The Aperiodic CSI-RS beam used in RLM / BFR shall be the same as the beam configured for Periodic CSI-RS also used in RLM / BFR. This case assumes the use of Aperiodic CSI-RS as a supplement during periods when Periodic CSI-RS is not transmitted.

[0090] In this case, for example, the base station 10 sets information indicating the same beam as the one set in Periodic CSI-RS as the setting information (e.g., TCI state) regarding the beam of Aperiodic CSI-RS to the terminal 20.

[0091] Alt2: The Aperiodic CSI-RS beam used in RLM / BFR shall be the same as the beam set in CORESET.

[0092] The beam for Aperiodic CSI-RS may be the same as, or different from, the beam for Periodic CSI-RS configured for BFD. Furthermore, a greater number of PDCCH beams may be assumed for BFD.

[0093] Alt3: No restrictions are placed on the Aperiodic CSI-RS beam used in RLM / BFR.

[0094] <Examples 1-3> In Examples 1-3, the choice between using Aperiodic CSI-RS or Periodic CSI-RS for RLM / BFR is selected based on the conditions.

[0095] For example, if LBT is required for signal transmission, base station 10 will determine that Aperiodic CSI-RS should be used for RLM / BFR and will cause terminal 20 to use Aperiodic CSI-RS for RLM / BFR (depending on the DCI or RRC settings described later).

[0096] Furthermore, when using a carrier on a specific band (e.g., an unlicensed band), the base station 10 may determine that Aperiodic CSI-RS should be used for RLM / BFR and may perform an action to cause terminal 20 to use Aperiodic CSI-RS for RLM / BFR.

[0097] The same embodiment (Example 1-1, Example 1-2, or Example 1-3) may be applied to both RLM and BFR, or different embodiments may be applied to RLM and BFR.

[0098] (Example 2) Next, Example 2 will be described. In Example 2, an extended DCI of the existing DCI is used to trigger the Aperiodic CSI-RS for RLM / BFD.

[0099] An example of operation in Embodiment 2 will be described with reference to Figure 5 mentioned above. In S101, configuration information regarding Aperiodic CSI-RS is transmitted from the base station 10 to the terminal 20 via an RRC message. This configuration information may be, for example, existing information disclosed in Non-Patent Document 2 (such as the CSI-AperiodicTriggerStateList shown in Figure 11).

[0100] In S102, the extended DCI in Example 2 transmits an Aperiodic CSI-RS trigger (a measurement trigger for terminal 20) from base station 10 to terminal 20. This DCI contains information instructing the use of Aperiodic CSI-RS for RLM / BFD purposes.

[0101] Terminal 20 receives the Aperiodic CSI-RS and performs a measurement a certain time after receiving the DCI (S103, S104). This measurement is performed for RLM / BFD. From the perspective of base station 10, the DCI transmission triggers the transmission of the Aperiodic CSI-RS a certain time later.

[0102] More specific examples are described below as Examples 2-1, 2-2, and 2-3. Any two or all of Examples 2-1, 2-2, and 2-3 may be combined and implemented.

[0103] <Example 2-1> In Example 2-1, the DCI fields are expanded (e.g., by adding new fields). Existing formats (e.g., DCI format 0_1, DCI format 0_2) and existing RNTIs may be used as the DCI format and the RNTI used to scramble the DCI.

[0104] Alternatively, instead of extending the DCI fields, an Aperiodic CSI-RS trigger for RLM / BFD may be implemented by applying a different interpretation (reinterpretation) to the existing DCI fields (or their values).

[0105] As an extension of the DCI fields, for example, a purpose indication field may be added, and the purpose of the trigger may be indicated by the value of the purpose indication field.

[0106] Multiple purposes (purpose set) that can be indicated by the purpose indication field may be specified in the specification, or they may be set from base station 10 to terminal 20 by RRC. The purpose set may consist of one or more of the following purposes 1 to 7.

[0107] Purpose 1: Trigger for existing purposes (e.g., beam / CSI reporting, tracking) Purpose 2: Trigger for RLM measurement Purpose 3: Trigger for BFD measurement Purpose 4: Trigger for both RLM and BFD measurements Purpose 5: Trigger for RLM measurement or BFD measurement, or for both RLM and BFD measurement. purpose 6:purpose 1+purpose 2 / 3 / 4 purpose 7: purpose 1 + purpose 5 Regarding purpose 5 of the above purposes 1-7, the terminal 20 that receives the DCI may refer to the RRC settings to determine its purpose (RLM, BFD, or both). Furthermore, purposes 6 and 7 are indicated as being usable for both the existing purposes and the RLM / BFD purposes.

[0108] <Example 2-2> Example 2-2 uses a novel DCI format for triggering Aperiodic CSI-RS for RLM / BFD. When using the novel DCI format, the new fields from Example 2-1 may or may not be included.

[0109] When terminal 20 receives a DCI in a new DCI format from base station 10, it detects the new DCI format and determines that the DCI is for triggering the Aperiodic CSI-RS for RLM / BFD, and uses the CSI-RS specified in the DCI for the RLM / BFD measurement.

[0110] <Example 2-3> In Example 2-3, base station 10 scrambles the existing DCI format with a new RNTI (e.g., RLM-BFR-CSI-RNTI) and transmits it for the Aperiodic CSI-RS trigger for RLM / BFD.

[0111] Terminal 20, having successfully decoded the DCI using the new RNTI, determines that the DCI is for triggering the Aperiodic CSI-RS for RLM / BFD, and uses the CSI-RS specified by the DCI for the RLM / BFD measurement.

[0112] <Other examples (variations)> The DCIs in Examples 2-1, 2-2, and 2-3 may be UE-specific (terminal-specific), group-common (common to the group), or common within a cell.

[0113] Furthermore, in both Examples 2-2 and 2-3, the purpose indication field of Example 2-1 may or may not be included. If the DCI of Examples 2-2 and 2-3 includes the purpose indication field, the purpose set may be one, more, or all of purposes 2 to 7.

[0114] <Effects of Example 2> In Example 2, terminal 20, upon receiving the DCI, can determine whether the Aperiodic CSI-RS triggered by the DCI is intended for CSI / beam reporting or RLM / BFD. Furthermore, because the DCI allows for precise determination of the trigger's purpose, existing procedures (Rel-16 A-CSI report triggering procedure) can be used, and existing RRC configuration information can be utilized.

[0115] (Example 3) Next, Example 3 will be described. In Example 3, in order to implement the Aperiodic CSI-RS trigger for RLM / BFD, RRC configuration information that extends existing RRC configuration information is used.

[0116] An example of operation in Embodiment 3 will be described with reference to Figure 5. In S101, configuration information regarding Aperiodic CSI-RS is transmitted from the base station 10 to the terminal 20 via an RRC message. This configuration information is an extension (or modification) of existing configuration information disclosed, for example, in Non-Patent Document 2.

[0117] In S102, for example, an Aperiodic CSI-RS trigger (a measurement trigger for terminal 20) is transmitted from base station 10 to terminal 20 by an existing DCI. This DCI includes the CSI request field, as explained in Figure 11.

[0118] A specific CSI-AperiodicTriggerState is specified by the CSI request field.

[0119] In Example 3, the CSI-AperiodicTriggerState specified by the CSI request field is associated with the Aperiodic CSI-RS configuration information for RLM / BFD. Therefore, terminal 20 can receive the Aperiodic CSI-RS based on the Aperiodic CSI-RS configuration information and perform measurements for RLM / BFD (S103, S104).

[0120] More specific examples are described below as Examples 3-1, 3-2, 3-3, and 3-4. Any two, any three, or all of Examples 3-1, 3-2, 3-3, and 3-4 may be used in combination.

[0121] <Example 3-1> Conventionally, only periodic measurements were possible for RLM and BFD measurements. Therefore, in Example 3-1, it is possible to set the CSI-RS for RLM and BFD to an aperipdic setting.

[0122] In other words, in Example 3-1, the setting information for the Aperipdic CSI-RS is included in the setting information for the reference signals for RLM and BFD. When terminal 20 detects that the Aperipdic CSI-RS associated with the CSI-AperiodicTriggerState specified by the CSI request field is set for RLM / BFD, it uses the Aperipdic CSI-RS to perform measurements in RLM / BFD. There are two variations, Alt1 and Alt2, for using the Aperipdic CSI-RS set for RLM / BFD.

[0123] Alt1: The Aperipdic CSI-RS for RLM / BFD associated with CSI-AperiodicTriggerState may also be used for existing purposes (such as CSI / beam reporting).

[0124] Alt2: Whether or not the Aperipdic CSI-RS for RLM / BFD associated with CSI-AperiodicTriggerState may be used for existing purposes (such as CSI / beam reporting) may be specified in the RRC parameter of the Aperipdic CSI-RS configuration information.

[0125] <Specific example of Example 3-1> A specific example of the setting information in Example 3-1 will be explained.

[0126] For example, a new IE parameter (e.g., RadioLinkMonitoringRS-r17) is used as configuration information for the Aperipdic CSI-RS resource for RLM / BFD. In other words, configuration information containing the new IE parameter (e.g., RadioLinkMonitoringRS-r17) is sent from base station 10 to terminal 20 as configuration information for the Aperipdic CSI-RS resource for RLM / BFD.

[0127] RadioLinkMonitoringRS-r17 is configured as the Aperipdic CSI-RS configuration information for RLM / BFD, linked to the CSI-AperiodicTriggerState. As a result, terminal 20, triggered by DCI, can perform RLM / BFD measurements using the Aperipdic CSI-RS configured in RadioLinkMonitoringRS-r17, which is linked to the specified CSI-AperiodicTriggerState.

[0128] If Alt1 above applies, the Aperipdic CSI-RS for RLM / BFD associated with CSI-AperiodicTriggerState can also be used for existing purposes. If Alt2 above applies, RadioLinkMonitoringRS-r17 determines whether the Aperipdic CSI-RS for RLM / BFD associated with CSI-AperiodicTriggerState can also be used for existing purposes.

[0129] Figure 14 shows an example of RadioLinkMonitoringRS-r17 assuming Alt2. The purpose shown in Figure 14 allows you to specify whether the purpose of Aperipdic CSI-RS configured in RadioLinkMonitoringRS-r17 is RLM (rlf in Figure 14), BFR (beamFailure in Figure 14), or both.

[0130] <Example 3-2> In Example 3-2, the configuration information for CSI-AperiodicTriggerState is an extended version of the existing configuration information disclosed in Non-Patent Document 2. Figure 15 shows CSI-AperiodicTriggerState-r17, which is an example of the configuration information for CSI-AperiodicTriggerState in Example 3-2.

[0131] As shown in Figure 15, a TriggeringPurpose is included. The TriggeringPurpose indicates the purpose (use) of all Aperipdic CSI-RS associated with this CSI-AperiodicTriggerState-r17. TriggeringPurpose can be set to include RLM / BFD, existing purposes (CSI / beam reporting), etc. The example in Figure 15 shows that a subset of purposes 1-7, as described in Example 2, can be set.

[0132] Assume that terminal 20, which has the above configuration information including CSI-AperiodicTriggerState-r17, is specified by the DCI's CSI request field for a specific CSI-AperiodicTriggerState-r17.

[0133] For example, if terminal 20 determines from the TriggeringPurpose in the CSI-AperiodicTriggerState-r17 that the objective is RLM / BFD, it will use the Aperipdic CSI-RS associated with CSI-AperiodicTriggerState-r17 to measure RLM / BFD.

[0134] Furthermore, for example, if terminal 20 determines from the TriggeringPurpose in the CSI-AperiodicTriggerState-r17 that the purpose is both RLM and CSI reporting, it will use the Aperipdic CSI-RS associated with CSI-AperiodicTriggerState-r17 for both RLM measurement and CSI reporting.

[0135] <Effects of Example 3-2> In Example 3-2, the existing (Rel-16) Aperipdic CSI-RS report triggering procedure can be used to implement Aperipdic CSI-RS for RLM / BFD.

[0136] <Example 3-3> Next, Example 3-3 will be described. In Example 3-3, as in Example 3-2, the configuration information for CSI-AperiodicTriggerState is extended. More specifically, in Example 3-3, the configuration information for reporting settings within CSI-AperiodicTriggerState is extended from the existing configuration information disclosed in Non-Patent Document 2.

[0137] Figure 16 shows CSI-AperiodicTriggerState-r17, an example of CSI-AperiodicTriggerState in Example 3-3.

[0138] As shown in Figure 16, a TriggeringPurpose can be set for each CSI-AssociatedReportConfigInfo in the associatedReportConfigInfoList. The TriggeringPurpose indicates the purpose (use) of the Aperipdic CSI-RS associated with the corresponding CSI-AssociatedReportConfigInfo. TriggeringPurposes can include RLM / BFD, existing purposes (CSI / beam reporting), etc. The example in Figure 16 shows that a subset of purposes 1-7, as explained in Example 2, can be set.

[0139] Assume that terminal 20, which has the above configuration information including CSI-AperiodicTriggerState-r17, is specified by the DCI's CSI request field for a specific CSI-AperiodicTriggerState-r17.

[0140] For example, if terminal 20 determines that the objective is RLM / BFD from the TriggeringPurpose of a certain CSI-AssociatedReportConfigInfo in the CSI-AperiodicTriggerState-r17, it will use the Aperipdic CSI-RS associated with that CSI-AssociatedReportConfigInfo to measure RLM / BFD.

[0141] For example, if terminal 20 determines from the TriggeringPurpose of a certain CSI-AssociatedReportConfigInfo in the CSI-AperiodicTriggerState-r17 that the purpose is both RLM and CSI reporting, it will use the Aperipdic CSI-RS associated with that CSI-AssociatedReportConfigInfo for measuring RLM and also for measuring CSI reporting.

[0142] <Effects of Example 3-3> In Example 3-3, the existing (Rel-16) Aperipdic CSI-RS report triggering procedure can be used to implement Aperipdic CSI-RS for RLM / BFD.

[0143] Furthermore, in Example 3-3, a purpose can be set for each of several different report settings within a single CSI-AperiodicTriggerState. Therefore, for each of the several different report settings within a single CSI-AperiodicTriggerState, the associated Aperipdic CSI-RS can be used for its respective purpose.

[0144] On the other hand, in Example 3-2, one purpose is set for each CSI-AperiodicTriggerState. That is, the same purpose is set for all reporting settings included in a single CSI-AperiodicTriggerState. Therefore, all Aperipdic CSI-RS associated with multiple different report settings in a single CSI-AperiodicTriggerState are used for the same purpose.

[0145] <Example 3-4> Next, we will describe Example 3-4. In Example 3-4, the configuration information is extended so that the CSI-AperiodicTriggerStateList includes TriggerStates for RLM / BFD. In addition, a new structure is used for the structure of the TriggerState.

[0146] As examples of CSI-AperiodicTriggerStateList used in Example 3-4, Alt1 and Alt2 are described below.

[0147] Alt1: In Alt1, a CSI-AperiodicTriggerStateList is used that contains only the new CSI-AperiodicTriggerState for RLM / BFD. Figure 17 shows an example of the CSI-AperiodicTriggerStateList for Alt1. As shown in Figure 17, the CSI-AperiodicTriggerStateList for Alt1 contains only CSI-AperiodicTriggerStateRlm-r17, which is the new CSI-AperiodicTriggerState for RLM / BFD.

[0148] In Alt1, for example, terminal 20 determines whether to use an existing CSI-AperiodicTriggerStateList or a new CSI-AperiodicTriggerStateList based on the DCI received as a trigger for Aperipdic CSI-RS. For example, the DCI may contain instruction information indicating whether to use an existing CSI-AperiodicTriggerStateList or a new CSI-AperiodicTriggerStateList, and terminal 20 may make the decision based on that instruction information.

[0149] Furthermore, for example, the interpretation of the value of the DCI's CSI request field may differ from the conventional interpretation. For instance, if the value of the DCI's CSI request field is greater than or equal to a certain value, it may indicate that a new CSI-AperiodicTriggerStateList should be used; otherwise, it may indicate that an existing CSI-AperiodicTriggerStateList should be used.

[0150] Alt2:Alt12 uses a CSI-AperiodicTriggerStateList that includes existing CSI-AperiodicTriggerStates for existing purposes (such as CSI reporting) and new CSI-AperiodicTriggerStates for RLM / BFD. Figure 18 shows an example of the CSI-AperiodicTriggerStateList for Alt2. As shown in Figure 18, the CSI-AperiodicTriggerStateList for Alt1 includes existing CSI-AperiodicTriggerStates and a new CSI-AperiodicTriggerState for RLM / BFD, CSI-AperiodicTriggerStateRlm-r17.

[0151] For trigger DCI in Alt2, an existing DCI can be used. Terminal 20 uses an existing CSI-AperiodicTriggerState or CSI-AperiodicTriggerStateRlm-r17 according to the CSI request field of the DCI received from base station 10.

[0152] <Regarding CSI-AperiodicTriggerState in Example 3-4> The new CSI-AperiodicTriggerState for RLM / BFD in Examples 3-4 may include a list of Aperipdic CSI-RS resources for RLM / BFD, but without including reporting-related information. Below, Examples 1 and 2 show examples of the structure of CSI-AperiodicTriggerStateRlm-r17, which is a new CSI-AperiodicTriggerState for RLM / BFD.

[0153] Example 1: Figure 19 shows the CSI-AperiodicTriggerStateRlm-r17 for Example 1. In Example 1, each CSI-AperiodicTriggerStateRlm-r17 is associated with a list of Aperipdic CSI-RS resources for RLM / BFD.

[0154] In the example in Figure 19, RadioLinkMonitoringRS-r17 corresponds to the list. This Example 1 is also an example from Example 3-1. As the RadioLinkMonitoringRS-r17 shown in Figure 19, for example, the one shown in Figure 14 of Example 3-1 can be used.

[0155] Example 2: Figure 20 shows the CSI-AperiodicTriggerStateRlm-r17 for Example 2. In Example 2, each CSI-AperiodicTriggerStateRlm-r17 is associated with a list of Aperipdic CSI-RS resources for RLM / BFD.

[0156] In the example in Figure 20, the item indicated by NZP-CSI-RS-ResourceId corresponds to the list in question. The purpose of an Aperipdic CSI-RS resource for RLM / BFD can be set commonly for the set of Aperipdic CSI-RS resource lists (using PurposeCommon) or it can be set individually for each Aperipdic CSI-RS resource list (using PurposeSeparate).

[0157] <Effects of Example 3-4> According to Example 3-4, separate CSI-AperiodicTriggerStates can be used for RLM / BFD and for existing purposes (such as CSI reporting).

[0158] (Example 4) Next, Example 4 will be described. Example 4 is an example of new beam selection in BFR. In other words, Example 4 is an example in which terminal 20 is enabled to perform measurements using Aperiodic CSI-RS for the purpose of new beam selection in BFR.

[0159] The techniques described in Examples 2 and 3 can be applied to enable terminal 20 to perform measurements using Aperiodic CSI-RS for the purpose of selecting a new beam in the BFR. In other words, Example 4 is obtained by replacing "RLM / BFD" with "new beam selection" in the content described in Examples 2 and 3. More specifically, this is as shown in Examples 4-1 and 4-2 below.

[0160] <Example 4-1> Example 4-1 corresponds to Example 2. That is, the extension of DCI enables terminal 20 to perform measurements using Aperiodic CSI-RS for the purpose of new beam selection in BFR. Example 4-1 is obtained by replacing "RLM / BFD" with "new beam selection" in Example 2.

[0161] <Example 4-2> Example 4-2 corresponds to Example 3. That is, by extending the RRC setting information, terminal 20 is made able to perform measurements using Aperiodic CSI-RS for the purpose of new beam selection in BFR. Basically, Example 4-2 is obtained by replacing "RLM / BFD" with "new beam selection" in Example 3.

[0162] As a more specific example, Figure 21 shows an example of the configuration information used in Example 4-2 relative to Example 3-1. As shown in Figure 21, candidateBeamRSList-r17, which is a list of beams to be detected by Aperiodic CSI-RS measurement, is configured. The resources of each Aperiodic CSI-RS in candidateBeamRSList-r17 are configured by PRACH-A-CSI-ResourceDedicatedBFR-r1.

[0163] In Example 4-2 compared to Example 3-1, terminal 20 detects a new beam by measuring the Aperiodic CSI-RS specified in candidateBeamRSList-r17, which is linked to the triggering state specified in DCI.

[0164] Examples 3-2 to 3-4 are modified by replacing the objective "RLM / BFD" with "new beam selection" in Examples 3-2 to 3-4 to obtain Example 4-2. Furthermore, a correspondence between Aperiodic CSI-RS resources usable for new beam selection and PRACH resources may be established.

[0165] (modified version) Next, we will describe a modified example that can be applied to any of Examples 1 to 4.

[0166] <Example 1> A relationship may be defined between the Aperiodic CSI-RS beam triggered for RLM / BFR and the beam used for LBT sensing. This relationship may be specified in the specification or configured from base station 10 to terminal 20. Examples of such relationships are given in Examples 1 to 3 below.

[0167] Example 1: Assume that the Aperiodic CSI-RS beam triggered for RLM / BFR and the beam used for LBT sensing have the same direction and width (thickness).

[0168] Example 2: Assume that the Aperiodic CSI-RS beam triggered for RLM / BFR and the beam used for LBT sensing have the same direction but different widths. For example, the beam width of the Aperiodic CSI-RS is made narrower than the beam width used for LBT sensing.

[0169] Example 3: The Aperiodic CSI-RS beam triggered for RLM / BFR and the beam used for LBT sensing are assumed to have different directions and widths. For example, the space defined by the direction and width of the Aperiodic CSI-RS beam is included in the space defined by the direction and width of the beam used for LBT sensing corresponding to COT.

[0170] <Modification 2> Each embodiment in Examples 1 to 4 may be applied when a specific frequency range is used at the base station 10 and terminal 20. The specific frequency range may be 52.6 to 71 GHz.

[0171] <Variation 3> Each embodiment in Examples 1 to 4 may be applicable when certain conditions are met. For example, whether or not the operation of using Aperiodic CSI-RS for RLM / BFR can be performed may be determined by whether LBT operation is ON or OFF, or whether the band used is an unlicensed band or a licensed band.

[0172] For example, when LBT operation is ON (or when the band being used is an unlicensed band), the base station 10 may transmit DCI as described in Example 2, thereby causing the terminal 20 to use Aperiodic CSI-RS for RLM / BFR.

[0173] Furthermore, when LBT operation is ON (or when the band being used is an unlicensed band), the base station 10 may perform the RRC settings described in Example 3 to cause the terminal 20 to use Aperiodic CSI-RS for RLM / BFR.

[0174] <Modification 4> Example 2 (DCI extension) and Example 3 (RRC extension) may be implemented in combination. The same applies to Example 4, which corresponds to Example 2 (DCI extension) and Example 3 (RRC extension).

[0175] <Modification 5> For each example described in Examples 1 to 4, the terminal 20 may be configured / instructed / reported, etc., according to Examples 1 to 4 below, regarding whether or not it will use it.

[0176] Example 1: Configure terminal 20 using higher-layer parameters (e.g., RRC, MAC CE).

[0177] Example 2: Terminal 20 reports to base station 10 via UE capability.

[0178] Example 3: Specify in the specifications.

[0179] Example 4: Determined by settings from higher-layer parameters and reported UE capability (combination of Example 1 and Example 2).

[0180] <Variation 6> Modification 6 is an example regarding UE capability. The UE capabilities shown in Examples 1 to 8 below are defined, and any of the UE capabilities may be reported from terminal 20 to base station 10. This operation corresponds to the operation in S100 of Figure 5.

[0181] Example 1: UE capability indicating whether terminal 20 supports Aperiodic CSI-RS for RLM / BFR.

[0182] Example 2: UE capability indicating whether terminal 20 supports only Aperiodic CSI-RS for RLM / BFR.

[0183] Example 3: UE capability indicating whether terminal 20 supports Periodic CSI-RS in addition to Aperiodic CSI-RS for RLM / BFR.

[0184] Example 4: UE capability indicating whether terminal 20 supports a new DCI format that triggers Aperiodic CSI-RS for RLM / BFR.

[0185] Example 5: UE capability indicating whether terminal 20 supports existing DCI formats using a new RNTI that triggers Aperiodic CSI-RS for RLM / BFR.

[0186] Example 6: UE capability indicating whether terminal 20 supports existing DCI formats using existing RNTIs that trigger Aperiodic CSI-RS for RLM / BFR.

[0187] Example 7: UE capability indicating whether terminal 20 supports Aperiodic CSI-RS for the purpose of measuring RLM / BFR, in addition to existing purposes (e.g., beam / CSI reporting, tracking).

[0188] Example 8: UE capability indicating whether terminal 20 supports RRC configuration information to determine the purpose for which Aperiodic CSI-RS is used.

[0189] The technology according to this embodiment, as described above, provides a technology that enables a terminal in a wireless communication system to properly perform fault detection and recovery.

[0190] (Device configuration) Next, we will describe an example of the functional configuration of the base station 10 and terminal 20 that perform the processes and operations described above.

[0191] <Base station 10> Figure 22 is a diagram showing an example of the functional configuration of the base station 10. As shown in Figure 22, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Figure 22 is merely an example. The names of the functional categories and functional units can be anything as long as they can perform the operations according to the embodiment of the present invention. Also, the transmitting unit 110 and the receiving unit 120 may be collectively referred to as the communication unit.

[0192] The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 and obtaining information from the received signals, for example, information from a higher layer. The transmitting unit 110 also has the function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DCI via PDCCH, data via PDSCH, etc. to the terminal 20.

[0193] The setting unit 130 stores pre-configured setting information and various setting information to be transmitted to the terminal 20 in a storage device provided by the setting unit 130, and reads it from the storage device as needed.

[0194] The control unit 140 schedules DL reception or UL transmission of terminal 20 via the transmission unit 110. The control unit 140 also includes a function for LBT (Low-Block Transmission). The functions related to signal transmission in the control unit 140 may be included in the transmission unit 110, and the functions related to signal reception in the control unit 140 may be included in the reception unit 120. The transmission unit 110 may also be called a transmitter, and the reception unit 120 may be called a receiver.

[0195] <Terminal 20> Figure 23 shows an example of the functional configuration of terminal 20. As shown in Figure 23, terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Figure 12 is merely an example. Any functional classification and name of functional unit is acceptable as long as it can perform the operations according to the embodiment of the present invention. The transmitting unit 210 and the receiving unit 220 may be collectively referred to as the communication unit.

[0196] The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and acquires signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals, DCI via PDCCH, data via PDSCH, etc. transmitted from the base station 10. Alternatively, for example, the transmitting unit 210 may transmit PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel), etc. to another terminal 20 as D2D communication, and the receiving unit 120 may receive PSCCH, PSSCH, PSDCH or PSBCH, etc. from the other terminal 20.

[0197] The setting unit 230 stores various setting information received from the base station 10 or other terminals by the receiving unit 220 in a storage device provided in the setting unit 230, and reads it from the storage device as needed. The setting unit 230 also stores pre-configured setting information. The control unit 240 controls the terminal 20. The control unit 240 also includes a function to perform LBT (Loop Beta Testing).

[0198] The terminal and base station in this embodiment may be configured as the terminal and base station described in the following sections. Furthermore, the following measurement methods may be implemented.

[0199] <Configuration of Examples 2 and 4> (Section 1) A receiving unit that receives downlink control information from the base station, Based on the trigger provided by the downlink control information, a control unit performs measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal received from the base station. A terminal equipped with the following features. (Section 2) The aforementioned downlink control information includes the purpose of a non-periodic reference signal. Based on the above objective, the control unit determines that the aperiodic reference signal is a reference signal to be used for wireless link monitoring or beam fault recovery. The terminal described in paragraph 1. (Section 3) The control unit determines, based on the format of the downlink control information, that the aperiodic reference signal is a reference signal used for radio link monitoring or beam fault recovery. The terminal described in paragraph 1 or 2. (Section 4) The control unit determines, based on the RNTI used to scramble the downlink control information, that the aperiodic reference signal is a reference signal to be used for radio link monitoring or beam fault recovery. A terminal as described in any one of paragraphs 1 through 3. (Section 5) It is equipped with a transmission unit that transmits downlink control information to the terminal, The transmitting unit transmits a non-periodic reference signal based on the trigger provided by the downlink control information, and the terminal performs measurements for wireless link monitoring or beam fault recovery based on the non-periodic reference signal. Base station. (Section 6) The steps include receiving downlink control information from the base station, Based on the trigger provided by the downlink control information, the steps include performing measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal received from the base station. A measurement method for a terminal, comprising the following features.

[0200] Any of the above configurations provides a technology that enables a terminal in a wireless communication system to properly perform fault detection and recovery. According to paragraph 2, the purpose can be explicitly understood. According to paragraphs 3 and 4, the terminal can understand the purpose even if it is not explicitly included.

[0201] <Configuration of Examples 3 and 4> (Section 1) A receiving unit that receives setting information for a non-periodic reference signals used for radio link monitoring or beam fault recovery from a base station, Based on a trigger from downlink control information received from the base station, the control unit performs measurements for radio link monitoring or beam fault recovery using the non-periodic reference signal. A terminal equipped with the following features. (Section 2) A receiving unit that receives configuration information including the purpose of a non-periodic reference signal from a base station, Based on a trigger from downlink control information received from the base station, a control unit performs measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal specified by the setting information, according to the purpose. A terminal equipped with the following features. (Section 3) The aforementioned objective is included in each triggering state in the setting information The terminal described in paragraph 2. (Section 4) The aforementioned configuration information includes a list of triggering states, All triggering states in the above list are information specifying a non-periodic reference signal for radio link monitoring or beam fault recovery, or Some of the triggering states in the above list are information that specifies a non-periodic reference signal for radio link monitoring or beam fault recovery. The terminal described in paragraph 2 or 3. (Section 5) It includes a transmitting unit that transmits configuration information, including the purpose of a non-periodic reference signal, to a terminal. The transmitting unit transmits downlink control information, and at the terminal, based on the trigger provided by the downlink control information, measurements for wireless link monitoring or beam fault recovery are performed using a non-periodic reference signal specified by the setting information, according to the purpose. Base station. (Section 6) The steps include receiving configuration information from the base station, including the purpose of the non-periodic reference signal, Based on a trigger from downlink control information received from the base station, the steps include performing measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal specified by the setting information, depending on the purpose. A measurement method performed by a terminal, comprising the following features.

[0202] Any of the above configurations provides a technology that enables a terminal in a wireless communication system to properly perform fault detection and recovery. According to paragraph 3, an objective can be set for each triggering state. According to paragraph 4, variations of the triggering state list can be realized.

[0203] (Hardware configuration) The block diagrams (Figures 22 and 23) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may be realized by combining the above one device or the above multiple devices with software.

[0204] Functions include, but are not limited to, judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. As mentioned above, the method of implementation is not particularly limited.

[0205] For example, the base station 10, terminal 20, etc. in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 24 is a diagram showing an example of the hardware configuration of the base station 10 and terminal 20 according to one embodiment of the present disclosure. The above-mentioned base station 10 and terminal 20 may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0206] In the following explanation, the term "device" can be read as "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and terminal 20 may include one or more of the devices shown in the figure, or it may be configured without some of the devices.

[0207] Each function in the base station 10 and terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of the reading and writing of data in the storage device 1002 and auxiliary storage device 1003.

[0208] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may consist of a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.

[0209] Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes a computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 140 of the base station 10 shown in Figure 22 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in Figure 23 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above-described processes have been explained as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may also be transmitted from the network via a telecommunications line.

[0210] The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of this disclosure.

[0211] The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disc, a digital multipurpose disc, a Blu-ray® disc), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0212] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may be configured to include high-frequency switches, duplexers, filters, frequency synthesizers, etc., in order to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the transmitting and receiving antennas, amplifier section, transmitting and receiving section, transmission path interface, etc., may be implemented by the communication device 1004. The transmitting and receiving section may be implemented in a physically or logically separated manner, with a transmitting section and a receiving section.

[0213] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0214] Furthermore, each device, such as the processor 1001 and the storage device 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or different buses may be configured for each device.

[0215] Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0216] (Supplement to the embodiment) While embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention, and matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. Regarding the processing procedures described in the embodiments, the order of processing may be changed as long as it does not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be implemented in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to an embodiment of the present invention and the software operated by the processor of the terminal 20 according to an embodiment of the present invention may be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

[0217] Furthermore, the notification of information is not limited to the embodiments / models described herein and may be carried out by other methods. For example, the notification of information may be carried out by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information (MIB (Master Information Block), SIB (System Information Block))), other signals, or combinations thereof. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.

[0218] Each aspect / embodiment described in this disclosure may be applied to at least one of the following systems: LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (new Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), and other appropriate systems, as well as next-generation systems extended based thereon. Furthermore, multiple systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A with 5G).

[0219] The processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described herein may be reordered, provided they are consistent with each other. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.

[0220] In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one of the other network nodes (for example, an MME or S-GW, but not limited to these). Although the above example illustrates the case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

[0221] The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.

[0222] Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.

[0223] The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).

[0224] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0225] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0226] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0227] In addition, terms used in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of the channel and symbol may be a signal (signaling). Also, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, cell, frequency carrier, etc.

[0228] The terms “system” and “network” as used in this disclosure are interchangeable.

[0229] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a given value, or other corresponding information. For example, wireless resources may be indicated by an index.

[0230] The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0231] In this disclosure, terms such as "base station (BS)", "wireless base station", "base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", "carrier", and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0232] A base station can accommodate one or more (e.g., three) cells. If a base station accommodates multiple cells, the entire coverage area of ​​the base station can be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms “cell” or “sector” refer to part or all of the coverage area of ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0233] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0234] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or several other appropriate terms.

[0235] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during 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.

[0236] Furthermore, the term "base station" in this disclosure may be interpreted as "terminal." For example, the various aspects / embodiments of this disclosure may be applied to a configuration in which communication between a base station and a terminal is replaced with communication between multiple terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything)). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.

[0237] Similarly, the term "terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the same functions as the terminal described above.

[0238] As used in this disclosure, the terms “determining” and “determining” may encompass a wide variety of actions. “Determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiry (e.g., searching in a table, database, or other data structure), and ascertaining. “Determining” may also include, for example, receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."

[0239] The terms "connected" and "coupled," or any variations thereof, mean any direct or indirect connection or coupling between two or more elements and can include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements can be physical, logical, or a combination thereof. For example, "connected" may be read as "accessed." As used in this disclosure, two elements can be considered to be "connected" or "coupled" to each other using at least one of one or more electric wires, cables, and printed electrical connections, as well as, by way of several non-limiting and non-inclusive examples, electromagnetic energy having wavelengths in the radio frequency region, microwave region, and optical (both visible and invisible) region.

[0240] The reference signal can also be abbreviated as RS (Reference Signal) and may be referred to as a Pilot depending on the applicable standard.

[0241] As used in this disclosure, the description "based on" does not mean "based only on" unless otherwise specified. In other words, the description "based on" means both "based only on" and "based at least on."

[0242] Any reference to an element using designations such as "first," "second," etc. used in this disclosure does not generally limit the quantity or order of those elements. These designations can be used in this disclosure as a convenient way to distinguish between two or more elements. Thus, a reference to a first and a second element does not mean that only two elements can be employed, or that the first element must precede the second element in any way.

[0243] The "means" in the configuration of each of the above devices may be replaced with a "section," "circuit," "device," etc.

[0244] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0245] A wireless frame may consist of one or more frames in the time domain. Each of these frames in the time domain may be called a subframe. A subframe may further consist of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0246] Numerical logic may be communication parameters applied to at least one of the transmission and reception of a signal or channel. Numerical logic may include, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, and specific windowing processes performed by the transceiver in the time domain.

[0247] A slot may consist of one or more symbols in the time domain (such as OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.). A slot may also be a time unit based on neurology.

[0248] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. Minislots may also be called subslots. Minislots may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0249] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Different names may be used for each of these terms.

[0250] For example, one subframe may be called a Transmission Time Interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one mini-slot may be called a TTI. In other words, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, mini-slot, etc., instead of a subframe. Also, one slot may be called a unit time. The unit time may differ from cell to cell depending on the neurology.

[0251] Here, TTI refers to, for example, the smallest unit of time for scheduling in wireless communication. For example, in an LTE system, the base station schedules each terminal 20 to allocate wireless resources (such as the frequency bandwidth and transmission power available to each terminal 20) in TTI units. However, the definition of TTI is not limited to this.

[0252] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc. are mapped may be shorter than the given TTI.

[0253] Furthermore, if one slot or one mini-slot is referred to as TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit of scheduling. In addition, the number of slots (number of mini-slots) that constitute the minimum time unit of scheduling may be controlled.

[0254] A TTI with a time length of 1ms may also be called a normal TTI, long TTI, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may also be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, mini slot, sub slot, slot, etc.

[0255] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

[0256] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.

[0257] Furthermore, the time domain of the RB may contain one or more symbols and may be the length of one slot, one minislot, one subframe, or one TTI. Each TTI, subframe, etc., may consist of one or more resource blocks.

[0258] One or more RBs may also be called a Physical RB (PRB), Sub-Carrier Group (SCG), Resource Element Group (REG), PRB pair, RB pair, etc.

[0259] Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.

[0260] A Bandwidth Part (BWP), also known as a partial bandwidth, may represent a subset of consecutive common resource blocks (RBs) for a particular neurology system in a given carrier. These common RBs may be identified by an index of the RBs relative to a common reference point of the carrier. A Bandwidth Part (PRB) may be defined and numbered within a given BWP.

[0261] A BWP may include BWPs for UL (UL BWP) and BWPs for DL ​​(DL BWP). One or more BWPs may be configured within a single carrier for a UE.

[0262] At least one of the configured BWPs may be active, and the UE does not need to assume that it will send or receive a given signal / channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be read as "BWP".

[0263] The structures such as the above-mentioned radio frames, sub-frames, slots, mini-slots, and symbols are merely illustrative. For example, the number of sub-frames included in a radio frame, the number of slots per sub-frame or radio frame, the number of mini-slots included in a slot, the number of symbols and RBs included in a slot or mini-slot, the number of sub-carriers included in an RB, and the number of symbols within a TTI, symbol length, cyclic prefix (CP) length, etc. can be variously changed.

[0264] In the present disclosure, for example, when articles are added by translation, such as a, an, and the in English, the present disclosure may include that the nouns following these articles are in the plural form.

[0265] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other". Note that the term may also mean "A and B are each different from C". Terms such as "separate", "coupled", etc. may also be interpreted in the same way as "different".

[0266] Each aspect / embodiment described in the present disclosure may be used alone, in combination, or switched for use during execution. Also, the notification of predetermined information (for example, the notification of "being X") is not limited to being explicitly performed, and may be performed implicitly (for example, by not performing the notification of the predetermined information).

[0267] As described above in detail about the present disclosure, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented as modified and changed aspects without departing from the spirit and scope of the present disclosure defined by the description of the claims. Therefore, the description of the present disclosure is for the purpose of illustrative explanation and has no restrictive meaning for the present disclosure.

Explanation of Reference Numerals

[0268] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 devices 210 Transmitter 220 Receiver 230 Setting section 240 Control Unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device

Claims

1. A receiving unit that receives downlink control information from the base station, A control unit that performs measurements for radio link monitoring or beam fault recovery based on a non-periodic reference signal received from the base station. A terminal equipped with the following features.

2. The aforementioned downlink control information includes the purpose of a non-periodic reference signal. Based on the above objective, the control unit determines that the aperiodic reference signal is a reference signal to be used for wireless link monitoring or beam fault recovery. The terminal according to claim 1.

3. It is equipped with a transmission unit that transmits downlink control information to the terminal, The transmitting unit transmits a non-periodic reference signal, and the terminal uses the non-periodic reference signal to perform measurements for wireless link monitoring or beam fault recovery. Base station.

4. The steps include receiving downlink control information from the base station, The steps include: performing measurements for radio link monitoring or beam fault recovery using a non-periodic reference signal received from the base station; A measurement method for a terminal, comprising the following features.

Images