Terminal device, base station device, and wireless communication system

Abstract

This terminal device includes a reception unit, a control unit, and a transmission unit. The reception unit receives a reference signal. The control unit compares a first threshold value and a measurement result of the reference signal. The control unit sets a second threshold value set in accordance with the first threshold value during a first period for determining whether to transmit the measurement result of the reference signal. The control unit then determines whether to transmit the measurement result of the reference signal by using the second threshold value. When the control unit has determined to transmit the measurement result of the reference signal, the transmission unit transmits the measurement result of the reference signal.

Description

Terminal device, base station device, and wireless communication system

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

[0002] In today's networks, traffic from mobile devices (smartphones and feature phones) accounts for the majority of network resources. Furthermore, the traffic used by mobile devices is expected to continue to expand. In addition to traffic used by mobile devices, IoT (Internet of Things) services (e.g., transportation systems, smart meters, and monitoring systems for devices) are also being developed. Therefore, networks are being required to support services with diverse requirements. In order to accommodate such diverse services, the communication standards for fifth-generation mobile communications (5G or NR (New Radio)) (for example, Non-Patent Documents 1 to 14) include, in addition to the standard technologies of 4G (fourth-generation mobile communications), eMBB (Enhanced Mobile Broadband), Massive MTC (Machine Type Communications), and URLLC (Ultra-Reliable and Low Latency Communications). The standards are being developed assuming support for many use cases.

[0003] In addition, in the working group of the 3rd Generation Partnership Project (3GPP (registered trademark)), an international standardization project, extension technologies for the above communication standards are currently being continuously studied and standardized.

[0004] For example, a working group of 3GPP has been studying lower layer triggered mobility (LTM) technology, and LTM has been introduced in Release 18.

[0005] 3GPP TS 37.324 V17.0.03GPP TS 37.340 V18.0.03GPP TS 38.201 V18.0.03GPP TS 38.202 V18.1.03GPP TS 38.211 V18.1.03GPP TS 38.212 V18.1.03GPP TS 38.213 V18.1.03GPP TS 38.214 V18.1.03GPP TS 38.215 V18.1.03GPP TS 38.300 V18.0.03GPP TS 38.321 V18.0.03GPP TS 38.322 V18.0.03GPP TS 38.323 V18.0.03GPP TS 38.331 V18.0.0

[0006] The LTM introduced in Release 18 triggers cell switching at the physical layer of a terminal device, for example. To further improve the efficiency of LTM latency, a function has been considered in which, for example, conditions are set in the terminal device and measurement results are transmitted to the base station device only when the conditions are met. To prevent frequent LTM (the "ping pong" problem) when channel conditions are severe, a time-to-trigger method, for example, has been considered. Time-to-trigger attempts to determine whether further measurement results satisfy the conditions within a certain period of time after the measurement results satisfy the conditions, thereby increasing the likelihood of resolving the "ping pong" problem. However, if channel conditions change drastically during the time-to-trigger period, the measurement results may not be transmitted, potentially resulting in LTM not being performed.

[0007] As a result, reports sent from the terminal device to the base station device may not be processed appropriately, and for example, reports may not be sent in situations where they are required, and LTM may not be implemented.

[0008] The disclosed technology has been developed in consideration of the above, and aims to enable reports sent from a terminal device to a base station device to be processed taking into account the status of the terminal device.

[0009] One aspect provides a terminal device having a receiving unit that receives a reference signal, a control unit that compares a measurement result of the reference signal with a first threshold, and a transmitting unit that transmits the measurement result, wherein the control unit sets a second threshold that is set according to the first threshold during a first period for determining whether to transmit the measurement result, and determines whether to transmit the measurement result using the second threshold.

[0010] It is possible to provide a terminal, a base station, a wireless communication system, etc. that can process reports sent from a terminal device to a base station device taking into account the status of the terminal device.

[0011] FIG. 1 is a diagram illustrating an example of a wireless communication system according to an embodiment. FIG. 2 is a diagram illustrating an example of a functional configuration of a base station device according to this embodiment. FIG. 3 is a diagram illustrating an example of a functional configuration of a terminal device according to this embodiment. FIG. 4 is a diagram illustrating an example of a slot configuration according to this embodiment. FIG. 5 is a diagram illustrating an example of the relationship between the value μ, slots, frames, and subframes according to this embodiment. FIG. 6 is a diagram illustrating an example of an LTM Cell Switch process in the MAC layer of a terminal device. FIG. 7 is an example showing the relationship between upper layer parameters. FIG. 8 is a diagram illustrating an example of a field of an LTM Cell Switch Command MAC CE. FIG. 9 is a diagram illustrating an example of an LTM Cell Switch procedure. FIG. 10 is a diagram illustrating an example of an event trigger and a time-to-trigger. FIG. 11 is a diagram illustrating an example of applying an offset to a threshold in Example 1. FIG. 12 is a diagram illustrating an example of a method for determining a report trigger condition according to Example 3. FIG. 13 is a diagram illustrating an example of a trigger report format according to this embodiment. Fig. 14 is a diagram showing an example of the hardware configuration of a base station device in this embodiment. Fig. 15 is a diagram showing an example of the hardware configuration of a terminal device in this embodiment.

[0012] The present embodiment will be described in detail below with reference to the drawings. The problems and embodiments in this specification are merely examples and do not limit the scope of the rights of the present application. In particular, even if the expressions used are different, the technology of the present application can be applied as long as they are technically equivalent, and do not limit the scope of the rights. Furthermore, each embodiment can be combined as appropriate within the scope of not causing any contradiction in the processing content.

[0013] Furthermore, the terms used and technical contents described in this specification may be those described in specifications and contributions as standards related to communications, such as 3GPP, as appropriate. Examples of such specifications include those described in Non-Patent Documents 1 to 14.

[0014] Hereinafter, embodiments of a terminal device, a base station device, and a wireless communication system disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the disclosed technology is not limited to the following embodiments. Embodiment

[0015] FIG. 1 is a diagram illustrating an example of a wireless communication system 1 according to a first embodiment. The wireless communication system 1 may include a base station device 100A, a base station device 100B, a terminal device 200A, a terminal device 200B, and a terminal device 200C. When the terminal device 200A, the terminal device 200B, and the terminal device 200C are not distinguished from each other, they are simply referred to as the terminal device 200. The base station device 100A forms a cell C10. The cell C10 may be referred to as the coverage of the base station device 100A. The base station device 100B forms a cell C11. The cell C11 may be referred to as the coverage of the base station device 100B. When the base station device 100A and the base station device 100B are not distinguished from each other, they are simply referred to as the base station device 100. The terminal device 200 is located within the coverage of one of the base station devices 100 .

[0016] The base station device 100 may be, for example, a small radio base station such as a macro radio base station or a pico radio base station (including a micro radio base station, a femto radio base station, etc.), or may be a radio base station of various scales, and may be referred to as a radio communication device, a communication device, a transmitting device, etc. The terminal device 200 may be, for example, a radio terminal such as a mobile phone, a smartphone, a PDA (Personal Digital Assistant), a personal computer, a vehicle, or any of various devices or equipment (sensor devices, etc.) having a radio communication function, and may be referred to as a radio communication device, a communication device, a receiving device, a mobile station, etc.

[0017] The base station device 100 is connected to a network device (not shown) (a higher-level device or another base station) via a wired connection. Note that the base station device 100 may be connected to the network device wirelessly instead of via a wired connection.

[0018] The base station device 100 may be configured such that the wireless communication function with the terminal device 200 and the digital signal processing and control functions are separated into separate devices. In this case, the device having the wireless communication function can be called an RRH (Remote Radio Head), and the device having the digital signal processing and control functions can be called a BBU (Base Band Unit). The RRHs may be installed extending from the BBU, and they may be connected by a wired connection such as optical fiber. Alternatively, they may be connected wirelessly. Instead of the RRH and BBU described above, the base station device 100 may be separated into, for example, a Central Unit (CU), a Distributed Unit (DU), and a Radio Unit (RU). The DU includes, for example, a MAC (Media Access Control) layer function. The DU may also include, for example, a function of an RLC (Radio Link Control) layer. The RU includes at least an RF wireless circuit. The DU and RU may also be integrated into one unit.

[0019] On the other hand, the terminal device 200 communicates with the base station device 100 via wireless communication.

[0020] Note that the base station device 100 performs processing for establishing a Radio Resource Control (RRC) connection when an RRC connection has not been established with the terminal device 200. Note that the processing for establishing an RRC connection may include a random access procedure.

[0021] Next, the base station device 100 will be described. Fig. 2 is a diagram showing an example of a functional configuration diagram of the base station device 100 in this embodiment. The base station device 100 has a wireless communication unit 110, a control unit 120, a storage unit 130, and a communication unit 140.

[0022] The wireless communication unit 110 is composed of a transmitting unit 111 and a receiving unit 112, and performs wireless communication with the terminal device 200. Specifically, the transmitting unit 111 transmits to the terminal device 200 downlink signals such as a random access procedure signal, a downlink physical signal, an RRC layer signal, a downlink data signal, and a downlink control signal.

[0023] Furthermore, the receiving unit 112 can receive uplink signals transmitted from the terminal device 200, such as random access procedure signals, RRC layer signals, uplink data signals, and uplink control signals.

[0024] The control unit 120 controls the base station device 100. Specifically, it can control the establishment of an RRC connection with the terminal device 200, signal processing of signals received by the receiving unit 212, creation of transport blocks (TBs), mapping of the transmission blocks to radio resources, etc. The control unit 120 can also perform control related to LTM. For example, the control unit 120 controls the transmission unit 111 to transmit a signal instructing measurement of a measurement signal at a cell switch destination.

[0025] The storage unit 130 can store, for example, downlink data signals.

[0026] The communication unit 140 connects to and communicates with a network device (e.g., a higher-level device or another base station) via a wired or wireless connection. The data signal received by the communication unit 140 and intended for the terminal device 200 can be stored in the storage unit 130.

[0027] Next, the terminal device 200 will be described. Fig. 3 is a diagram showing an example of a functional configuration diagram of the terminal device 200 in this embodiment. As shown in Fig. 3, the terminal device 200 includes a communication unit 210, a control unit 220, and a storage unit 230. These components are connected to enable unidirectional or bidirectional input and output of signals and data. The communication unit 210 can be described as being divided into a transmission unit 211 and a reception unit 212.

[0028] The transmitter 211 transmits data signals and control signals by wireless communication via an antenna. Note that the antenna may be common for both transmission and reception. The transmitter 211 transmits uplink signals such as random access procedure signals, RRC layer signals, uplink data signals, and uplink control signals.

[0029] The receiving unit 212 receives downlink signals, such as a random access procedure signal, a downlink data signal, and a downlink control signal, transmitted from the base station device 100. The received signals may also include reference signals used for channel estimation and demodulation.

[0030] The control unit 220 controls the terminal device 200. Specifically, the control unit 220 can control the establishment of an RRC connection with the base station device 100, signal processing of signals received by the receiving unit 212, creation of transmission blocks (TBs), mapping of the transmission blocks to radio resources, etc. The control unit 220 also controls the terminal device 200 to perform control related to LTM. For example, the control unit 220 controls the terminal device 200 to measure measurement signals transmitted from the base station device 100B, which is the cell switching destination, and report the measurement results to the base station device 100A.

[0031] The storage unit 230 can store, for example, an uplink data signal. The storage unit 230 can also store configuration information (or setting information) related to wireless communication transmitted from the base station device 100. Note that the configuration information is, for example, configuration information of CSI-RS resources or reports, or information related to LTM.

[0032] The communication unit 110 of the base station device 100 and the communication unit 210 of the terminal device 200 may be configured to include an antenna port.

[0033] The uplink may be referred to as an uplink. The downlink may be referred to as a downlink. The uplink may be a communication link through which the terminal device 200 transmits to the base station device 100. The downlink may be a communication link through which the base station device 100 transmits to the terminal device 200.

[0034] The uplink channel may include some or all of a PUSCH (Physical Uplink Shared Channel), a PUCCH (Physical Uplink Control Channel), a PRACH (Physical Random Access Channel), and an SRS (Sounding Reference Signal).

[0035] The uplink signal may be a signal transmitted via a PUSCH, a PUCCH, a PRACH, and an SRS.

[0036] The downlink channel may include some or all of the following: a PDSCH (Physical Downlink Shared Channel), a PDCCH (Physical Downlink Control Channel), a PBCH (Physical Broadcast Channel), an SSB (Synchronization Signal Block), and a CSI (Channel State Information)-RS (Reference Signal).

[0037] The downlink signal may be a signal transmitted via a PDSCH, a PDCCH, and a PBCH. The downlink signal may include a downlink reference signal. The SSB may be a synchronization signal (SS) / PBCH block.

[0038] The higher layer parameters may be any or all of the following: RRC parameters, MAC Media Access Control Element (CE), System Information Block (SIB), and Master Information Block (MIB).

[0039] Here, an example of slots for wireless communication between the base station device 100 and the terminal device 200 will be described.

[0040] FIG. 4 is a diagram showing an example of a slot configuration in this embodiment. The radio frame shown in FIG. 4 may be 10 milliseconds (msec). The radio frame may also be called a frame. The radio frame may also be called a system frame. The radio frame is composed of, for example, 10 subframes.

[0041] In the radio frame shown in Fig. 4, for example, the length of the time axis of the radio frame is determined according to subcarrier spacing (SCS). For example, the subcarrier spacing is SCS = 15 x 2 μ (kHz). In other words, μ = 0 means that the subcarrier spacing is 15 kHz. Note that hereinafter, μ may be referred to as the value μ or the value μ that determines the subcarrier spacing.

[0042] In addition, with a subcarrier spacing of 15 kHz, one frame may include 10 slots. One slot may include, for example, 14 OFDM symbols. An OFDM symbol may be composed of, for example, multiple physical resource blocks (PRBs). One physical resource block may be composed of, for example, 12 subcarriers.

[0043] The slot is, for example, n using the subcarrier spacing μ. ｓ μ n ｓ μ For example, in one subframe, {0, 1, 2, ..., N ｓｌｏｔ subframe, μ-1} in ascending order. ｓ μ For example, in one frame, {0, 1, 2, ..., N ｓｌｏｔ ｆｒａｍｅ、μ -1} in increasing order. One slot is N ｓｙｍｂ ｓｌｏｔ may contain N OFDM symbols. ｓｙｍｂ ｓｌｏｔ may have different values ​​depending on the length of the cyclic prefix (CP).

[0044] FIG. 5 is a diagram showing an example of the relationship between the value μ, slots, frames, and subframes in this embodiment. Note that a normal CP may be used for all values ​​μ. Also, an extended CP may be used when μ=2. Regarding the length of the CP in the time domain, the normal CP may be shorter than the extended CP. Also, FIG. 5 shows the number N of slots included in one radio frame for the value μ. ｓｌｏｔ ｆｒａｍｅ、μ1 shows an example of the number of slots included in one subframe for values ​​μ and μ. In the case of normal CP, for example, one slot includes 14 OFDM symbols. In the case of extended CP, for example, one slot includes 12 OFDM symbols. In the first embodiment, normal CP is assumed unless otherwise specified. Note that the technology in the first embodiment can be applied to normal CP and extended CP.

[0045] Note that subcarrier spacing may be referred to as numerology. Different numerologies may mean different subcarrier spacings.

[0046] The time resource may be one or more OFDM symbols, one or more slots, or one or more system frames.

[0047] A frequency resource may be one or more subcarriers. A frequency resource may be one or more PRBs.

[0048] An antenna port may be defined such that the channel on which a symbol is transmitted on a certain antenna port can infer the channel on which a different symbol is transmitted on the same antenna port, i.e., multiple symbols transmitted on the same antenna port at different times can be considered to be transmitted on the same channel.

[0049] If the long-scale property of a channel in which a certain symbol is transmitted on one antenna port can be used to predict the channel in which a different symbol is transmitted on the other antenna port, the two antenna ports may be said to be in Quasi Co-location (QCL). The long-scale property may include some or all of one or more of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial reception parameters.

[0050] For each numerology and carrier, the resource grid is N ｇｒｉｄ，ｘ ｓｉｚｅ，μ ×N ｓｃ ＲＢ subcarriers and N ｓｙｍｂ subframe, may be defined as μ OFDM symbols. ｓｃ ＲＢ may be 12.

[0051] FR1 (Frequency Range 1) may have a carrier frequency of 6 GHz or less, and FR2 may have a carrier frequency of 6 GHz or more.

[0052] TDD (Time Division Duplex) may also be called Unpaired Spectrum.

[0053] The Random Access Preamble Sequence supports four or more different lengths, which may include at least 139, 571, 839, and 1151.

[0054] A random access preamble sequence of length 839 may be applied to 1.25 kHz and / or 5 kHz SCSs. A random access preamble sequence of length 139 may be applied to 15 kHz, 30 kHz, 60 kHz, 120 kHz, 480 kHz, and 960 kHz SCSs. A random access preamble sequence of length 571 may be applied to 30 kHz, 120 kHz, and / or 480 kHz SCSs. A random access preamble sequence of length 1151 may be applied to 15 kHz and / or 120 kHz SCSs.

[0055] Next, TDD (Time Division Duplex) will be described. In TDD, the base station apparatus 100 may determine a slot format. In TDD, the base station apparatus 100 may transmit slot format configuration information to the terminal apparatus 200. The terminal apparatus 200 may determine a slot format based on the slot format configuration information. The base station apparatus 100 may know the slot format of the terminal apparatus 200 in a cell included in the base station apparatus 100. The slot format configuration information may be one or more higher layer parameters or one or more physical layer signals.

[0056] In the downlink slots and / or downlink symbols, the terminal device 200 may receive a downlink channel and / or a downlink signal. For example, the terminal device 200 may receive a PDSCH, a PDCCH, a PBCH, a CSI-RS, or an SSB in the downlink slots and / or downlink symbols. In the uplink slots and / or uplink symbols, the terminal device 200 may receive an uplink channel and / or an uplink signal. For example, the terminal device 200 may transmit a PUSCH, a PUCCH, a PRACH, or an SRS in the uplink slots and / or uplink symbols. In the flexible slots and / or flexible symbols, the terminal device 200 may receive a downlink channel or a downlink signal scheduled in a DCI format. In the flexible slots and / or flexible symbols, the terminal device 200 may transmit an uplink channel or an uplink signal scheduled in a DCI format. The terminal device 200 may transmit the PRACH in a flexible slot and / or a flexible symbol.

[0057] If the terminal device 200 is not configured to monitor the PDCCH of DCI format 2_0 in a set of slot symbols indicated as flexible by tdd-UL-DL-ConfigurationCommon and / or tdd-UL-DL-ConfigurationDedicated, or if tdd-UL-DL-ConfigurationCommon and tdd-UL-DL-ConfigurationDedicated are not provided to the terminal device 200, the terminal device 200 may receive a PDSCH or CSI-RS in the set of slot symbols if the terminal device 200 receives a corresponding instruction in the DCI format.

[0058] A terminal device 200 configured to operate in the BWP (Bandwidth Part) of a serving cell may have a set of up to four BWPs configured by the upper layer of the serving cell. The set of BWPs may include an uplink BWP (UL BWP) and a downlink BWP (DL BWP). The DL BWP may be used by the terminal device 200 for reception in the downlink bandwidth. The DL BWP may be configured based on the upper layer parameter BWP-Downlink, or may be configured based on the upper layer parameter initialDownlinkBWP using a parameter set configured by the upper layer parameter BWP-DownlinkCommon and the upper layer parameter BWP-DownlinkDedicated. The UL BWP may be used for transmission in the uplink bandwidth by the terminal device 200. The UL BWP may be configured based on the upper layer parameter BWP-Uplink, or may be configured based on the upper layer parameter initialUplinkBWP using a parameter set (a set of parameters) configured by the upper layer parameter BWP-UplinkCommon and the upper layer parameter BWP-UplinkDedicated.

[0059] The terminal device 200 may transmit an uplink channel and / or an uplink signal in a UL BWP. The terminal device 200 may receive a downlink channel and / or a downlink signal in a DL BWP.

[0060] The serving cell may be a cell to which the terminal device 200 is connected. The candidate cell may be one or more target cells to which the terminal device 200 performs cell switching.

[0061] Here, the flow of LTM processing when SSB is the measurement target will be described.

[0062] The terminal device 200 may be indicated, by the higher layer parameter LTM-Config, one or more candidate cells and one or more SSBs for each candidate cell. The SSBs may be used by the terminal device 200 to acquire synchronization and / or measure one or more L1-RSRPs corresponding to the SSBs. The SSBs may be used to measure one or more L1-SINRs corresponding to the SSBs.

[0063] L1-RSRP (Layer 1-Reference Signal Received Power) may be the received power of a reference signal received by the terminal device 200. L1-RSRP may be a value indicating radio wave intensity. L1-SINR (Layer 1-Signal to Interference plus Noise power Ratio) may be the ratio of the power of a desired signal to the power of a signal other than the desired signal.

[0064] The Candidate Cell TCI State Activation or Deactivation MAC CE Command may activate the TCI State provided by the higher layer parameter Candidate-TCI-State-r18 and / or the higher layer parameter Candidate-TCI-UL-State-r18 in the candidate cell, which may be linked to the SSB or TRS of the corresponding candidate cell.

[0065] If the Candidate Cell TCI States Activation / Deactivation MAC CE command activates one or more TCI States, the LTM Cell Switch Command MAC CE may indicate one TCI State from the one or more activated TCI States. If the candidate cell TCI State activation or deactivation MAC CE command does not activate one or more TCI States, the LTM Cell Switch Command MAC CE may activate and indicate one TCI State from one or more TCI States provided by the higher layer parameter Candidate-TCI-State-r18 and / or the higher layer parameter Candidate-TCI-UL-State-r18.

[0066] After receiving the LTM Cell Switch Command MAC CE from the base station apparatus 100, the terminal apparatus 200 may deactivate TCI States other than the TCI State indicated by the LTM Cell Switch Command MAC CE.

[0067] The terminal device 200 may be provided with report configuration information (Report Configuration) for reporting L1-RSRP measurement results by LTM-CSI-ReportConfigToAddModList. The report configuration information may include the number of candidate cells and the number of SSBs for each candidate cell included in the candidate cells.

[0068] In one candidate cell, when the higher layer parameter ltm-UE-MeasuredTA-ID and the higher layer parameter ltm-ServingCellUE-MeasuredTA-ID of the serving cell are provided to the terminal device 200 and the two higher layer parameters have the same value, the terminal device 200 may estimate a timing advance to be applied to the first transmission on the candidate cell when a predetermined condition is satisfied after receiving a Cell Switch command instructing cell switching to the candidate cell.

[0069] The terminal device 200 may be provided with parameters for PRACH transmission in one or more candidate cells by an upper layer parameter EarlyUL-SyncConfig. The terminal device 200 may trigger PRACH transmission in a candidate cell by a PDCCH Order. The terminal device 200 may receive the PDCCH Order from the serving cell. The PDCCH Order may also include an indication of the candidate cell that will perform PRACH transmission.

[0070] The PDCCH Order may be an instruction from the base station device 100 to transmit a PRACH to the terminal device 200 using a PDCCH including DCI. The DCI may include information on candidate cells to which the PRACH is to be transmitted.

[0071] If the serving cell and the candidate cell operate in the same frequency band, and the terminal device 200 performs uplink transmissions to both cells that overlap in time, and the terminal device 200 does not support uplink transmissions that overlap in time, the terminal device 200 does not need to transmit on the serving cell.

[0072] If the serving cell and the candidate cell operate in the same frequency band, and the terminal device 200 performs uplink transmissions to both cells that overlap in time, and the terminal device 200 supports uplink transmissions that overlap in time, the terminal device 200 may prioritize power allocation for PRACH transmissions on the candidate cell.

[0073] If the serving cell and the candidate cell operate in the same frequency band, the terminal device 200 performs uplink transmissions to both cells that overlap in time, and the gap between the uplink transmissions of the candidate cell and the serving cell is less than N symbols, the terminal device 200 may not perform transmissions on the serving cell. The gap may be the number of symbols between the last symbol of the uplink transmission in the serving cell and the first symbol of the PRACH transmission in the candidate cell. The gap may be the number of symbols between the last symbol of the PRACH transmission in the candidate cell and the first symbol of the uplink transmission in the serving cell.

[0074] If the serving cell and the candidate cell operate in the same frequency band, and the terminal device 200 performs uplink transmissions to both cells that overlap in time, and the gap between the uplink transmissions of the candidate cell and the serving cell is less than N symbols, and the total transmission power of the terminal device 200 in the frequency band in which the uplink transmission is performed exceeds an upper limit, the terminal device 200 may prioritize the power allocation of PRACH transmissions on the candidate cell.

[0075] The terminal device 200 may transmit the PRACH in the candidate cell at a predetermined transmission power.

[0076] The terminal device 200 may be provided with an upper layer parameter CandidateTCI-State included in the upper layer parameter ltm-DL-OrJointTCI-StateToAddModList and / or an upper layer parameter CandidateTCI-UL-State included in the upper layer parameter ltm-UL-TCI-StateToAddModList by an LTM Cell Switch Command MAC CE included in the PDSCH reception in the serving cell. The upper layer parameters CandidateTCI-State and / or CandidateTCI-UL-State may indicate a TCI State applicable to uplink transmission and / or downlink reception in one candidate cell from one or more candidate cells. The one candidate cell may be determined by an LTM Cell Switch Command MAC CE. The one candidate cell may be indicated by an LTM Cell Switch Command MAC CE.

[0077] The terminal device 200 may assume that one or more DMRS antenna ports for PDCCH reception and PDSCH reception are quasi-co-location (QCL) with the SSB and / or TRS included in the TCI State. The QCL may be an attribute of type A and / or type D.

[0078] When SSB is configured as a source reference signal of the TCI State, the terminal device 200 does not need to expect that QCL Type A is notified.

[0079] When the CandidateTCI-State and / or the CandidateTCI-UL-State is instructed to the terminal device 200 by the LTM Cell Switch Command MAC CE, the terminal device 200 performs the following operations after the last symbol of the PUCCH or PUSCH that transmits the HARQ-ACK corresponding to the PDSCH reception including the LTM Cell Switch Command MAC CE: ＬＴＭ－ＲＲＣ－ｐｒｏｃｅｓｓｉｎｇ +T ＬＴＭ－ｐｒｏｃｅｓｓｉｎｇ +T ｆｉｒｓｔ－ＲＳ +TＲＳ－ｐｒｏｃ +3 msec, CandidateTCI-State and / or CandidateTCI-UL-State may be applied. ＬＴＭ－ＲＲＣ－ｐｒｏｃｅｓｓｉｎｇ T may be the time for decoding and validity and / or compliance check of the RRC configuration information of the LTM target cell indicated in the LTM Cell Switch command. ＬＴＭ－ｐｒｏｃｅｓｓｉｎｇ T may be the terminal equipment side processing time consisting of applying the target cell parameters and L1 / L2 changes. ｆｉｒｓｔ－ＲＳ is the time to acquire the fine time tracking and complete timing information of the target cell. ＲＳ－ｐｒｏｃ may be the processing time of SSB. msec may be 1 / 1000 of a second. For example, 3 msec is 3 / 1000 of a second.

[0080] In the case of a PRACH-based LTM cell switch, the terminal device 200 may apply CandidateTCI-State to reception on the candidate cell and apply a spatial domain filter corresponding to CandidateTCI-State or CandidateTCI-UL-State to transmission on the candidate cell after completion of the random access procedure related to the PRACH transmission on the candidate cell and before a new TCI state is indicated for the candidate cell.

[0081] In the case of a RACH-less LTM cell switch, the terminal device 200 may apply CandidateTCI-State to reception on the candidate cell and apply a spatial domain filter corresponding to CandidateTCI-State or CandidateTCI-UL-State to transmission on the candidate cell before a new TCI state is indicated for the candidate cell.

[0082] The base station apparatus 100 may notify the terminal apparatus 200 that the LTM Cell Switch procedure will be performed by transmitting an LTM Cell Switch Command MAC CE to the terminal apparatus 200. The notification may be performed by a MAC entity.

[0083] FIG. 6 is a diagram showing an example of LTM Cell Switch processing in the MAC layer of the terminal device 200. It is assumed that the serving cell belongs to the base station device 100. The MAC layer includes a MAC entity that performs processing in the MAC layer. The lower layer and / or the MAC layer and / or the upper layer may belong to the terminal device 200. The lower layer may be the physical layer. The upper layer and / or the MAC layer may be included in the upper layer. The lower layer, MAC layer, and upper layer are included in the terminal device 200. The lower layer, MAC layer, and upper layer shown in FIG. 6 are performed, for example, according to the control of the control unit 220.

[0084] The lower layer of the terminal device 200 receives the LTM Cell Switch Command MAC CE included in the PDSCH transmitted via the serving cell (step S10). Then, the lower layer of the terminal device 200 notifies the MAC layer of the received LTM Cell Switch Command MAC CE (step S11).

[0085] When the MAC layer receives the LTM Cell Switch Command MAC CE, it instructs or notifies the upper layer of the terminal device 200 that the LTM Cell Switch has been triggered and of the Target Configuration ID included in the LTM Cell Switch Command MAC CE (step S12).

[0086] The MAC layer of the terminal device 200 receives an instruction or notification regarding MAC processing from an upper layer of the terminal device 200 (step S13). The MAC layer of the terminal device 200 performs a first process, which is a MAC layer process, in response to the instruction or notification regarding MAC processing (step S14). Note that the first process is, for example, performing a MAC reset, or, if the value of the Timing Advance Command included in the LTM Cell Switch Command MAC CE is not FFF, performing processing of the received Timing Advance Command. Note that the Timing Advance Command is a process that, for example, considers that a RACH-less LTM cell switch is being performed. In addition, if the first process is associated with a secondary cell group (SCG), the MAC layer may notify or indicate to the upper layer that the random access procedure for the LTM cell switch will be skipped (step S15).

[0087] Furthermore, the first process includes processing of a measured Timing Advance Command, for example, when a MAC reset is performed, Timing Advance measurement is configured, and the terminal device 200 successfully measures the Timing Advance for a specified LTM target. The Timing Advance Command processing is processing that considers, for example, that a RACH-less LTM cell switch is being performed. If the first process is associated with an SCG (Secondary Cell Group), the MAC layer may notify or indicate to a higher layer that the Random Access procedure for the LTM cell switch will be skipped.

[0088] Furthermore, the first processing may include processing for assuming, in a RACH-less LTM cell switch, an SSB associated with a TCI State indicated by a TCI State ID included in an LTM Cell Switch Command MAC CE as an SSB to be used for selecting a Configured Uplink grant for an initial uplink transmission to a candidate cell.

[0089] The MAC layer notifies or instructs the lower layer about information regarding the TCI State information included in the LTM Cell Switch Command MAC CE (step S16).

[0090] Here, the parameters for channel measurement will be described.

[0091] In the case of CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), CRI (CSI-RS Resource Indicator), SSBRI (SS / PBCH Resource Block Indicator), LI (Layer Indicator), RI (Rank Indicator), L1-RSRP, L1-SINR, Capability Index, and TDCP (Time Domain Channel Properties), the terminal device 200 receives one or more CSI-ReportConfig report configurations (Reporting One or more reporting settings of LTM-CSI-ReportConfig (Reporting Settings), one or more resource settings of CSI-ResourceConfig (Resource Setting), one or more resource settings of LTM-CSI-ResourceConfig and / or one or more lists of trigger states given by the higher layer parameters CSI-AperiodicTriggerStateList and CSI-SemiPersistentOnPUSCH-TriggerStateList may be configured.

[0092] Each trigger state included in the higher layer parameter CSI-AperiodicTriggerStateList may contain a list of CSI-ReportConfigs or LTM-CSI-ReportConfigs indicating the channel resource set IDs and / or interference resource set IDs. The IDs may be indexes. The interference resource sets may only be present in the reporting configuration given by the CSI-ReportConfig. If the associated CSI-ReportConfig consists of a list of sub-configurations, one trigger state may further contain one or more csi-ReportSubConfigIDs.

[0093] Each trigger state included in the higher layer parameter CSI-SemiPersistentOnPUSCH-TriggerStateList may include one associated CSI-ReportConfig or LTM-CSI-ReportConfig. If the associated CSI-ReportConfig consists of a list of sub-configurations, one trigger state may further include one or more csi-ReportSubConfigIDs.

[0094] Each report setting of the higher layer parameter LTM-CSI-ReportConfig is associated with an LTM-CSI-ResourceConfig for channel measurements and may include parameters for time domain operation provided by the higher layer parameter ltm-ReportConfigType, the number of candidate cells provided by the higher layer parameter nrOfReportedCells, and the number of reference signals per candidate cell provided by nrOfReportedRS-PerCell. If the higher layer parameter spCellInclusion is set, each report setting of the higher layer parameter LTM-CSI-ReportConfig may include L1 measurement results associated with the current SpCell.

[0095] The time domain operation of LTM-CSI-ReportConfig is indicated by the higher layer parameter ltm-ReportConfigType, and may be set to any one of periodic, semiPersistentOnPUCCH, semiPersistentOnPUSCH, or periodic. When set to periodic, the terminal device 200 may periodically transmit CSI reports to the base station device 100 (serving cell). When set to semiPersistentOnPUCCH, the terminal device 200 may periodically transmit CSI reports to the base station device 100 (serving cell) using the PUCCH while receiving an instruction to start CSI report transmission and an instruction to stop CSI report transmission from the base station device 100. When configured in semiPersistentOnPUSCH, the terminal device 200 may periodically transmit a CSI report to the base station device 100 (serving cell) using the PUSCH while receiving an instruction to start CSI report transmission and an instruction to stop CSI report transmission from the base station device 100. In the CSI reports of periodic, semiPersistentOnPUCCH, and semiPersistentOnPUSCH, the set periodicity and set slot offset may be applied to the numerology of the UL BWP configured to transmit the CSI report.

[0096] In a terminal device 200 in which the higher layer parameter LTM-CSI-ReportConfig is set, for L1-RSRP measurement, any or all of aperiodic, semi-permanent, or periodic CSI may be associated with one Resource Setting specified in ltm-ResourcesForChannelMeasurement.

[0097] FIG. 7 is an example showing the relationship between upper layer parameters. Note that when an r and a number are added to the end of an upper layer parameter name (e.g., r18), the r and number are omitted unless otherwise specified. For example, ltm-SSB-Config and ltm-SSB-Config-r18 are the same. CSI-MeasConfig 801 may be linked to LTM-CSI-ReportConfig 802. Note that CSI-MeasConfig 801 may include LTM-CSI-ReportConfig 802. LTM-CSI-ReportConfig 802 may be linked to LTM-CSI-ResourceConfig 803. Note that LTM-CSI-ReportConfig 802 may include LTM-CSI-ResourceConfig 803. LTM-CSI-ResourceConfig 803 may be linked to LTM-CSI-SSB-ResourceConfig 804. Note that LTM-CSI-ResourceConfig 803 may include LTM-CSI-SSB-ResourceConfig 804. LTM-CSI-SSB-ResourceConfig 804 may be linked to LTM-Candidate 805. In addition, LTM-CSI-SSB-ResourceConfig 804 may include LTM-Candidate 805.

[0098] LTM-CSI-ReportConfig 802 may be used to configure reporting for the cell in which the LTM-CSI-ReportConfig is included. LTM-CSI-ResourceConfig 803 may be used to define one or more groups of CSI resources for one or more LTM Candidate Configurations. LTM-CSI-SSB-ResourceConfig 804 may be used to indicate SSB resources from one or more LTM candidate cells.

[0099] LTM-Candidate 805 may include some or all of the higher layer parameters included in information element 806. ltm-CandidateId 807 may include LTM candidate configuration information. ltm-CandidatePCI 808 may include the PCI (Physical Cell Index) of the SpCell in the configuration information included in ltm-CandidateConfig 810. Note that ltm-CandidatePCI 808 may include the cell ID of the LTM candidate cell. ltm-SSB-Config 809 may include SSB configuration information of the LTM candidate cell having the PCI of ltm-CandidatePCI 808. ltm-CandidateConfig 810 may contain an RRCReconfiguration message used to configure LTM candidate configuration information. ltm-ConfigComplete 811 may indicate whether the LTM candidate configuration information in ltm-CandidateConfig 810 is complete configuration information.

[0100] 8 is a diagram showing an example of fields in an LTM Cell Switch Command MAC CE. The values ​​of some or all of the fields included in the LTM Cell Switch Command MAC CE may correspond to parameters included in the higher layer parameter ltm-Candidate. For example, the Target Config ID included in the LTM Cell Switch Command MAC CE corresponds to ltm-CandidateId 807. In other words, when the Target Config ID is 0, it may correspond to configuration information in which ltm-CandidateId is 0. Furthermore, the Target Config ID may be 3 bits. The Timing Advance Command included in the LTM Cell Switch Command MAC CE may be applied to uplink transmission when the terminal device 200 performs uplink transmission to a candidate cell. The TCI state ID included in the LTM Cell Switch Command MAC CE may correspond to LTM-TCI-Info. The UL TCI state ID included in the LTM Cell Switch Command MAC CE may correspond to LTM-TCI-Info. The Random Access Preamble index, SS / PBCH index, and PRACH Mask index included in the LTM Cell Switch Command MAC CE may be used when the terminal device 200 transmits a PRACH to a candidate cell after receiving the LTM Cell Switch Command MAC CE. The PRACH transmission may be transmitting a preamble corresponding to the Random Access Preamble Index using an RO indicated by the PRACH Mask index in a RACH Occasion linked to the SS / PBCH index. The SS / PBCH may be an SSB. The LTM Cell Switch Command MAC CE may be referred to as a cell switch command.

[0101] FIG. 9 is a diagram showing an example of an LTM Cell Switch procedure. The first cell is, for example, a cell belonging to the base station device 100. This procedure may also be applied when there are multiple candidate cells. The terminal device 200 receives first information including information about a second cell, which is a candidate cell, from the first cell (step S20). The first information is, for example, configuration information required for uplink transmission and / or downlink reception in the second cell. The first information may be a CSI-MeasConfig in the second cell and higher layer parameters linked to the CSI-MeasConfig. The first information may include a report trigger condition. The terminal device 200 may receive a reference signal transmitted from the first cell based on the first information received in step S20 and perform channel measurement (step S21A). Furthermore, the terminal device 200 may receive a reference signal transmitted from the second cell based on the first information received in step S20, and perform channel measurement (step S21B). The reference signal may be an SSB or a CSI-RS. The terminal device 200 uses the measurement results measured in steps S21A and / or S21B to determine whether the measurement results satisfy a report trigger condition set based on the first information (step S21C). Note that steps S21A, S21B, and S21C may be collectively referred to as step S21. The reference signal transmitted from the first cell to the terminal device 200 in step S21A is an example of a first reference signal. The reference signal transmitted from the second cell to the terminal device 200 in step S21B is an example of a second reference signal. If the report trigger condition is satisfied in step S21, the terminal device 200 may transmit the measurement results performed in step S21 to the first cell (step S22). The first cell may transmit a PDCCH Order to the terminal device 200 (step S23) and instruct the second cell to transmit a PRACH. Here, configuration information necessary for the PRACH transmission may be set based on the first information. The terminal device 200 may transmit a PRACH to the second cell based on the first information (step S24).The RACH Occasion used for the PRACH transmission may be a RACH Occasion linked to the SSB Index included in the PDCCH Order. The transmission of the PRACH by the terminal device 200 in step S24 may be referred to as RACH-Based LTM. The terminal device 200 may not transmit the PRACH in step S24, and not transmitting the PRACH may be referred to as RACH-Less LTM. In the case of RACH-Based LTM, the second cell may receive the PRACH transmitted by the terminal device 200 in step S24, measure Timing Advance information, and transmit information regarding the Timing Advance to the first cell. The Timing Advance Command may be derived from the Timing Advance information. Furthermore, the information related to the Timing Advance may include the Timing Advance information and / or the Timing Advance Command. The first cell may activate the TCI State of the terminal device 200 (step S26). Note that step S26 may not be performed. The first cell may transmit an LTM Cell Switch Command MAC CE to the terminal device 200 to instruct a cell switch to the second cell (step S27). The terminal device 200 may transmit a PRACH to the second cell (step S28). Note that if the terminal device 200 has transmitted the PRACH in step S24, the terminal device 200 may not transmit the PRACH in step S28. Also, if the value of the Timing Advance Command included in the LTM Cell Switch Command MAC CE is other than FFF, the terminal device 200 may not transmit the PRACH in step S28. The terminal device 200 may start uplink transmission to the second cell (step S29). Also, the second cell may instruct the terminal device 200 to measure beams using CSI-RS (step S30).

[0102] When the terminal device 200 determines whether a report trigger condition exists, the terminal device 200 may use either the filtered measurement results or the unfiltered measurement results to determine whether the report trigger condition exists. In this embodiment, unless otherwise specified, the filtered measurement results and / or all of the unfiltered measurement results may be used to determine whether the report trigger condition exists. Furthermore, filtering may be performed in a higher layer. Furthermore, filtering may be performed in a physical layer.

[0103] When the terminal device 200 filters the measurement results, the terminal device 200 may perform the filtering using the formula shown in Formula 1. M ｎ may be the latest measurement result. ｎ may be an updated value of the filtered measurement. ｎ is used, for example, to determine the report trigger condition. ｎ may be a measurement report included in a report transmitted by the terminal device 200. ｎ－１ may be old filtered measurements. When the first measurement is received from the physical layer, F ０ is M １ In addition, in the upper layer parameter MeasObjectNR, a=2 ―（ｋｉ／４） where k i may be the measurement type value filterCoefficient corresponding to the ith QuantityConfigNR in the quantityConfigNR-List, where i may be indicated by quantityConfigIndex in the upper layer parameter MeasObjectNR, and a may be the filtering coefficient.

[0104] (Formula 1) F ｎ = (1-a) x F ｎ－１ + a × M ｎ

[0105] If the terminal device 200 does not filter the measurement results, M ｎ is used, for example, to determine the report trigger condition. If the terminal device 200 does not filter the measurement results, Mｎ may be a measurement report included in a report transmitted by the terminal device 200. ｎ may be the measurement results of any or all of RSRP, SINR, and RSRQ.

[0106] If the measurement result measured by the terminal device 200 satisfies a condition set by the base station device 100, the terminal device 200 may report the measurement result to the base station device 100. In other words, if the measurement result measured by the terminal device 200 satisfies a condition set by the base station device 100, the terminal device 200 may be triggered to transmit a report of the measurement result. The measurement result reported by the terminal device 200 may be different from or the same as the measurement result that satisfied the condition. In this embodiment, for example, the condition set by the base station device 100 is referred to as a report trigger condition.

[0107] In this embodiment, unless otherwise specified, the measurement results measured by the terminal device 200 may be any one or all of RSRP, SINR, and RSRQ.

[0108] The report trigger may be the terminal device 200 transmitting a report to the base station device 100 when a certain condition is satisfied. The report trigger may also be called an event trigger.

[0109] The base station device 100 may configure some or all of the events Event LTM1, Event LTM2, Event LTM3, Event LTM4, and Event LTM5 in the terminal device 200. The events may include a determination of a report trigger condition. The events may also be operations of the terminal device 200 and / or the base station device 100 based on the determination result of the report trigger condition. Event LTM1, Event LTM2, Event LTM3, Event LTM4, and Event LTM5 may be referred to as events.

[0110] In Event LTM1, the report trigger condition may be that the measurement results of one or more beams included in the serving cell are better than a threshold. That is, when the terminal device 200 measures the channels of one or more beams included in the serving cell, and the measurement results are better than a threshold, the terminal device 200 may be triggered to transmit a report of the measurement results. Also, when the measurement results are equal to the threshold, the terminal device 200 may be triggered to transmit a report of the measurement results. In Event LTM1, satisfying the report trigger condition means, for example, that the measurement results of one or more beams included in the serving cell are better than a threshold.

[0111] In Event LTM2, the report trigger condition may be that the measurement result of one or more beams included in the serving cell is worse than a threshold. In other words, when the channel measurement result of the terminal device 200 for a beam included in the serving cell is worse than a threshold, the terminal device 200 may be triggered to transmit a report of the measurement result. Also, when the measurement result is the same as the threshold, the terminal device 200 may be triggered to transmit a report of the measurement result. In Event LTM2, satisfying the report trigger condition means, for example, that the measurement result of one or more beams included in the serving cell is worse than a threshold.

[0112] A report trigger condition for Event LTM3 may be that the measurement results of one or more beams included in the candidate cell are better than the measurement results of one or more beams included in the serving cell plus an offset. In other words, when the channel measurement results of one or more beams included in the candidate cell performed by the terminal device 200 are better than the measurement results of one or more beams included in the serving cell plus an offset, the terminal device 200 may be triggered to transmit a report of the measurement results. The offset may be an absolute value. The offset may be provided to the terminal device 200 from the base station device 100. The offset may be provided by a higher layer parameter. In Event LTM3, satisfying the report trigger condition means, for example, that the measurement results of one or more beams included in the candidate cell are better than the measurement results of one or more beams included in the serving cell plus an offset. The threshold for Event LTM3 may be the value of the measurement results of one or more beams included in the serving cell plus an offset.

[0113] In Event LTM4, the report trigger condition may be that the measurement results of one or more beams included in the candidate cell are better than a threshold. In other words, when the terminal device 200 measures the channels of one or more beams included in the candidate cell, and the measurement results are better than a threshold, the terminal device 200 may be triggered to transmit a report of the measurement results. Also, when the measurement results are the same as the threshold, the terminal device 200 may be triggered to transmit a report of the measurement results. In Event LTM4, satisfying the report trigger condition means, for example, that the measurement results of one or more beams included in the candidate cell are better than a threshold.

[0114] In Event LTM5, the report trigger condition may be that the measurement result of one or more beams included in the serving cell is worse than threshold 1 and the measurement result of one or more beams included in the candidate cell is better than threshold 2. In other words, when the measurement result of channel measurement of a beam included in the serving cell is worse than threshold 1 and the measurement result of channel measurement of a beam included in the candidate cell is better than threshold 2, the terminal device 200 may be triggered to transmit a report of the measurement result. Also, when the measurement result of a beam of the serving cell is the same as threshold 1, the terminal device 200 may be triggered to transmit a report of the measurement result. In Event LTM5, satisfying the report trigger condition means, for example, that the measurement result of one or more beams included in the serving cell is worse than threshold 1 and the measurement result of one or more beams included in the candidate cell is better than threshold 2.

[0115] The measurement result being better than the threshold may mean, for example, that the measurement result is greater than or equal to the threshold. The measurement result being worse than the threshold may mean, for example, that the measurement result is smaller than or equal to the threshold. The threshold may be an absolute value. The threshold may be provided from the base station device 100 to the terminal device 200. The threshold may be provided by an upper layer parameter. Satisfying the report trigger condition may mean satisfying the condition.

[0116] When the terminal device 200 is triggered to transmit a measurement result report, a time-to-trigger may be applied. The time-to-trigger may be a period for determining whether the measurement results for a predetermined time from when the transmission of the measurement result report is triggered satisfy a condition. For example, if all measurement results measured during the time-to-trigger period satisfy a condition, the terminal device 200 may transmit the measurement results or filtered measurement results to the base station device 100. For example, if one or more measurement results measured during the time-to-trigger period do not satisfy a condition, the terminal device 200 may cancel the transmission of the report. The time-to-trigger period may be a predetermined time. The predetermined time may be 0 seconds or more. The time-to-trigger period may be given by an upper layer parameter. The time-to-trigger period may be instructed by the base station device 100 to the terminal device 200. The measurement result used in the time-to-trigger period is M ｎ or F shown in Formula 1 ｎ The time-to-trigger is an example of a predetermined period.

[0117] FIG. 10 is a diagram showing an example of an event trigger and a time-to-trigger. In this example, it is assumed that the report trigger condition is satisfied when the measurement result exceeds a threshold 1006. For example, measurement result 1000 does not exceed the threshold 1006 and therefore does not satisfy the report trigger condition. Furthermore, measurement result 1001 exceeds the threshold 1006 and therefore satisfies, for example, the report trigger condition. From the point in time when this condition is satisfied, period 1007 (the time-to-trigger period) may begin. Furthermore, the duration of period 1007 may be provided by an upper layer parameter. Since measurement result 1002 satisfies the report trigger condition within period 1007, the terminal device 200 does not need to interrupt the time-to-trigger. Since the measurement result 1003 does not satisfy the report trigger condition within the period 1007, the terminal device 200 may interrupt the Time-to-Trigger at this point. In short, if the measurement result is equal to or less than the threshold value 1006, the terminal device 200 stops sending reports of the measurement result and ends the period 1007.

[0118] Here, if the channel environment temporarily changes during the time-to-trigger period, the report trigger condition may no longer be satisfied, and the transmission of the report may be canceled. This may result in a delay in the transmission of the measurement result report, making it difficult to implement LTM at the appropriate time. Therefore, in this embodiment, in Examples 1 to 3, a method that enables LTM to be implemented at the appropriate time will be described.

[0119] (First Embodiment) FIG. 11 is a diagram showing an example of applying an offset to a threshold in the first embodiment. Note that in this example, it is assumed that the report trigger condition is satisfied when the measurement result exceeds a threshold 1006. Furthermore, the same reference numerals are assigned to portions similar to those described in FIG. 10 , and description thereof will be omitted. The terminal device 200 may apply an offset 1100 to the threshold 1006. The offset may be applied simultaneously with the start of the time-to-trigger. The offset may be applied by the end of the time-to-trigger period 1007. When the terminal device 200 applies an offset to a threshold, the threshold may be overwritten with a value to which the offset has been applied. The new threshold may be a value obtained by applying the offset to the threshold. The original threshold may be the threshold before the offset is applied to the new threshold. For example, the threshold 1006 is the original threshold. For example, the threshold 1101 is the new threshold. Furthermore, for example, applying the offset 1100 to the threshold 1006 may result in the threshold being 1101. The terminal device 200 may determine whether or not the report trigger condition is satisfied using a new threshold within the time-to-trigger period 1007. The threshold 1006 is an example of a first threshold. The threshold 1101 is an example of a second threshold. The period 1007 is an example of a first period. The first period may also be described as a period for determining whether or not to transmit measurement results. The offset may be notified to the terminal device 200 from the base station device 100, or a preset value may be used. The base station device 100 notifies the offset using, for example, an RRC layer signal, a MAC layer signal, or a physical layer signal. For example, the base station device 100 may include offset information in the signal transmitted in step S20 of FIG. 9. The offset may also be selected by the terminal device 200 from an arbitrary range of values. The selection of the offset in the terminal device 200 may be based on, for example, a parameter corresponding to the moving speed of the terminal device 200. Furthermore, the threshold value 1006 is a threshold value used in, for example, any one of Event LTM1 to Event LTM5.

[0120] An offset may be applied to relax the threshold. For example, when an offset is applied to the threshold for Event LTM1, the new threshold is smaller than the original threshold. For example, when an offset is applied to the threshold for Event LTM2, the new threshold is larger than the original threshold. For example, when an offset is applied to the threshold for Event LTM3, the new threshold is smaller than the original threshold. For example, when an offset is applied to the threshold for Event LTM4, the new threshold is smaller than the original threshold. For example, when an offset is applied to the threshold for Event LTM5, the new threshold 1 is larger than the original threshold 1 and the new threshold 2 is smaller than the original threshold 2.

[0121] In this way, even if the measurement result temporarily deteriorates after the terminal device 200 triggers a report, the period 1007 is not interrupted, and the terminal device 200 can transmit a report of the measurement result. Also, if the deterioration of the measurement result is not temporary (in other words, if it continues), the reporting of the measurement result can be stopped. In other words, the report to be transmitted from the terminal device 200 to the base station device 100 can be processed appropriately based on the status of the terminal device.

[0122] (Example 2) The terminal device 200 may calculate an average of one or more measurement results measured within a time-to-trigger period, and determine whether the average satisfies the report trigger condition. For example, in Figure 10, the terminal device 200 may calculate an average using some or all of measurement results 1001, 1002, 1003, 1004, and 1005 during a period 1007, and determine whether the average is greater than a threshold value 1006.

[0123] In Event LTM1 and / or Event LTM3 and / or Event LTM4, an average of one or more measurement results measured within the Time-to-Trigger period may be calculated, and if the average is greater than a threshold, the terminal device 200 may consider that the report trigger condition is met. In Event LTM2, an average of one or more measurement results measured within the Time-to-Trigger period may be calculated, and if the average is less than a threshold, the terminal device 200 may consider that the report trigger condition is met. In Event LTM5, an average 1 of the measurement results of the serving cell measured within the time-to-trigger period 1007 is calculated, and an average 2 of the measurement results of the candidate cell measured within the time-to-trigger period 1007 is calculated. If the average 1 is smaller than the threshold 1 and the average 2 is greater than the threshold 2, the terminal device 200 may consider that the report trigger condition is satisfied.

[0124] In this way, even if the measurement result temporarily deteriorates after the terminal device 200 triggers a report, the period 1007 is not interrupted, and the terminal device 200 can transmit a report of the measurement result. In other words, the report to be transmitted from the terminal device 200 to the base station device 100 can be processed appropriately in consideration of the status of the terminal device.

[0125] (Example 3) Figure 12 is a diagram showing an example of a method for determining a report trigger condition in Example 3. In this example, it is assumed that the report trigger condition is satisfied when the measurement result exceeds a threshold value 1006. Furthermore, parts similar to those described in Figure 10 are assigned the same reference numerals, and description thereof will be omitted. If the measurement result 1200 does not satisfy the condition during the time-to-trigger period 1007, the terminal device 200 may use the next measurement result 1201 to determine whether to interrupt the time-to-trigger period 1007. If the difference between the measurement result 1201 and the threshold is greater than the difference between the measurement result 1200 and the threshold, the terminal device 200 may interrupt the time-to-trigger and not transmit a report. For example, in Fig. 12, if measurement result 1201 is smaller than measurement result 1200, terminal device 200 may interrupt Time-to-Trigger and not transmit a report. For example, in Fig. 12, if measurement result 1201 is larger than measurement result 1200, terminal device 200 may consider that measurement result 1200 and / or measurement result 1201 satisfy the condition. For example, in Fig. 12, if measurement result 1201 is larger than measurement result 1200 and measurement result 1201 is smaller than threshold value 1006, terminal device 200 may interrupt Time-to-Trigger and not transmit a report. For example, in FIG. 12, if measurement result 1201 is greater than measurement result 1200 and measurement result 1201 is greater than or equal to threshold value 1006, terminal device 200 may consider measurement result 1200 and / or measurement result 1201 to satisfy the condition.

[0126] In this way, even if the measurement result temporarily deteriorates after the terminal device 200 triggers a report, the period 1007 is not interrupted, and the terminal device 200 can transmit a report of the measurement result. In other words, the report to be transmitted from the terminal device 200 to the base station device 100 can be processed appropriately in consideration of the status of the terminal device.

[0127] Note that the contents of Examples 1 to 3 can be combined as appropriate within a range that does not cause inconsistencies. For example, within a first period, the terminal device 200 may compare the threshold 1101 to determine whether to suspend the report, and may compare the average of the measurement results for period 1007 with the threshold 1006 to determine whether to suspend the report. Furthermore, if the measurement results within the first period are worse than the threshold 1101, the terminal device 200 may compare the next measurement result with the threshold 1006 or the threshold 1101 to determine whether to suspend the report. In short, for example, if the measurement results continue to be worse than the threshold 1101, the terminal device 200 determines to suspend the report.

[0128] Note that even if the report trigger condition is satisfied, the terminal device 200 may not transmit a report during a period in which report transmission is prohibited. The period in which report transmission is prohibited may be instructed by the base station device 100. For example, when the terminal device 200 receives a Cell Switch Command from the base station device 100, the period in which report transmission is prohibited may start. When the terminal device 200 receives a TCI Activation Command from the base station device 100, the period in which report transmission is prohibited may start. When the Cell Switch ends, the period in which report transmission is prohibited may end. Note that the period in which report transmission is prohibited is an example of a second period.

[0129] In this embodiment, the report transmitted by the terminal device 200 when the report trigger condition is satisfied may be referred to as a triggered report.

[0130] The trigger report may include an SSB resource index (SSBRI) associated with one or more candidate cells measured by the terminal device 200, the best measurement result among the measurement results of the one or more candidate cells, and the difference therebetween. The number of candidate cells may be Lc. There may be Ms SSBRIs or CRIs per candidate cell. The number of entries included in one trigger report may be 2×Lc×Ms. For example, one trigger report may include Lc×Ms SSBRIs or CRIs and Lc×Ms measurement results corresponding to the SSBRIs or CRIs. Here, the Lc×Ms measurement results corresponding to the SSBRIs or CRIs may include one strongest measurement result and Lc×Ms−1 differences between the strongest measurement result and the strongest measurement result.

[0131] FIG. 13 is a diagram showing an example of a trigger report format in this embodiment. The resource indicator 1300 may include a CRI or SSBRI value. The resource indicator 1300 may set the CRI or SSBRI to a value corresponding to a larger measurement result. For example, the measurement result for SSBRI #1 has a larger value than the measurement result for SSBRI #2. The measurement result 1301 may include a measurement result corresponding to an entry in the resource indicator 1300. For example, the measurement result corresponding to SSBRI #1 (1302) is measurement result #1 (1303). For example, the measurement result corresponding to SSBRI #2 (1304) may be measurement result #2 (1305). The number of entries in the resource indicator 1300 may be Lc×Ms. The number of entries in the measurement result 1301 may be Lc×Ms.

[0132] The terminal device 200 may include the measurement results of the serving cell in the trigger report. The base station device 100 may instruct the terminal device 200 whether or not to include the measurement results of the serving cell. The base station device 100 instructs the terminal device 200 to transmit the measurement results of the serving cell, for example, using the upper layer parameter spCellInclusion. When the upper layer parameter spCellInclusion is set to the value true, the terminal device 200 may include the measurement results of the serving cell in the report and transmit the report to the base station device 100. The measurement results of the serving cell may be set as the first entry of the report. For example, when the upper layer parameter spCellInclusion is set to the value true, the terminal device 200 may set the SSBRI of the serving cell in the resource indicator 1300 and set the measurement results of the serving cell in the measurement result 1301. The higher layer parameter spCellInclusion being set with a value of true may mean transmitting measurements of the serving cell.

[0133] When the upper layer parameter spCellInclusion is set to the value of true, the terminal device 200 may set the SSBRI of the serving cell to the first entry in the resource indicator 1300, set the SSBRI with the largest measurement result among the candidate cells to the second entry, and set the SSBRI with the second largest measurement result among the candidate cells to the third entry, and may set the measurement result of the serving cell to the first entry in the measurement result 1301, set the largest measurement result among the candidate cells to the second entry, and set the difference between the largest measurement result among the candidate cells and the second largest measurement result among the candidate cells to the third entry.

[0134] If the upper layer parameter spCellInclusion is not set to the value of true, the terminal device 200 may set the SSBRI with the largest measurement result among the candidate cells to the first entry in the resource indicator 1300, set the SSBRI with the second largest measurement result among the candidate cells to the second entry, set the largest measurement result among the candidate cells to the first entry in the measurement results 1301, and set the difference between the largest measurement result among the candidate cells and the second largest measurement result among the candidate cells to the second entry.

[0135] The terminal device 200 may include the measurement results of the serving cell in a report and then transmit the report in Event LTM1, Event LTM2, Event LTM3, Event LTM4, or Event LTM5. The terminal device 200 may include the measurement results of the serving cell in a report and then transmit the report in Event LTM1, Event LTM2, Event LTM3, Event LTM4, or Event LTM5, regardless of the higher layer parameter spCellInclusion.

[0136] The terminal device 200 may report measurement results of one or more cells for one or more cells instructed by the base station device 100. The terminal device 200 may report only measurement results of cells that satisfy a report trigger condition for one or more cells instructed by the base station device 100. The terminal device 200 may not transmit reports for measurement results of cells that do not satisfy the condition. When the terminal device 200 reports only measurement results of cells that satisfy only the report trigger condition, the terminal device 200 may set entries of reports corresponding to cells that are not being transmitted to 0 and transmit them. For example, an SSBRI that does not satisfy the report trigger condition may be set in the resource indicator 1300, and an entry of the measurement result 1301 corresponding to the SSBRI may be set to 0 and transmitted. Setting to 0 may mean zero-padding.

[0137] In this embodiment, cell switching, cell switch, and LTM cell switch may have the same meaning. Hardware configuration of each device in each embodiment

[0138] The hardware configuration of each device in the wireless communication system of each embodiment will be described with reference to FIGS.

[0139] Fig. 14 is a diagram showing an example of the hardware configuration of a base station device 100 according to this embodiment. As shown in Fig. 14, the base station device 100 has, as hardware components, for example, an RF (Radio Frequency) circuit 320 equipped with an antenna 310, a CPU (Central Processing Unit) 330, a DSP (Digital Signal Processor) 340, a memory 350, and a network IF (Interface) 360. The CPU 330 is connected via a bus so as to enable input and output of various signals and data signals. The memory 350 includes at least one of a RAM (Random Access Memory) such as an SDRAM (Synchronous Dynamic Random Access Memory), a ROM (Read Only Memory), and a flash memory, and stores programs, control information, and data signals.

[0140] The correspondence between the functional configuration of the base station device 100 shown in Fig. 2 and the hardware configuration of the base station device 100 shown in Fig. 14 will be described. The transmitter 111 and receiver 112 (or communication unit 140) are realized by, for example, an RF circuit 320, or an antenna 310 and an RF circuit 320. The control unit 120 is realized by, for example, a CPU 330, a DSP 340, a memory 350, a digital electronic circuit (not shown), etc. Examples of digital electronic circuits include an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programming Gate Array), and an LSI (Large Scale Integration). The storage unit 130 is realized by, for example, the memory 350.

[0141] In addition, in the base station apparatus 100, a plurality of data signals to be transmitted in a plurality of subbands can be generated, and the filters that generate these signals may be configured independently for each subband.

[0142] 15 is a diagram showing an example of the hardware configuration of the terminal device 200 in this embodiment. As shown in FIG. 15, the terminal device 200 has, as hardware components, an RF circuit 420 including an antenna 410, a CPU 430, a DSP 440, and a memory 450. The terminal device 200 may further have a display device such as an LCD (Liquid Crystal Display) connected to the CPU 430. The memory 450 includes at least one of a RAM such as an SDRAM, a ROM, and a flash memory, and stores programs, control information, and data signals.

[0143] The correspondence between the functional configuration of the terminal device 200 shown in Fig. 3 and the hardware configuration of the terminal device 200 shown in Fig. 15 will be described. The transmitter 211 and receiver 212 (or communication unit 210) are realized by, for example, an RF circuit 420, or an antenna 410 and an RF circuit 420. The control unit 220 is realized by, for example, a CPU 430, a DSP 440, a memory 450, a digital electronic circuit (not shown), etc. Examples of digital electronic circuits include an ASIC, an FPGA, and an LSI. The storage unit 230 is realized by, for example, the memory 450.

[0144] In each embodiment, examples of base station devices, terminal devices, and repeaters are described, but the disclosed technology is not limited to these and can be applied to various devices, such as electronic devices mounted on automobiles, trains, airplanes, artificial satellites, etc., electronic devices transported by drones, etc., robots, AV equipment, home appliances, office equipment, vending machines, and other household equipment.

[0145] Furthermore, although the embodiments have been described using fifth-generation mobile communications as an example, the application of the disclosed technology is not limited to this. For example, the disclosed technology may be applied to mobile communications of different generations, such as sixth and seventh generations.

[0146] 1 Wireless communication system 100 100A 100B Base station device C10 C11 Cell 110 Wireless communication unit 111 Transmitter 112 Receiver 120 Control unit 130 Memory unit 140 Communication unit 200 200A 200B 200C Terminal device 210 Communication unit 211 Transmitter 212 Receiver 220 Control unit 230 Memory unit 310 Antenna 320 RF circuit 330 CPU 340 DSP 350 Memory 360 Network IF 410 Antenna 420 RF circuit 430 CPU 440 DSP 450 Memory

Claims

1. A terminal device comprising: a receiving unit that receives a reference signal; a control unit that compares a measurement result of the reference signal with a first threshold; and a transmitting unit that transmits the measurement result, wherein the control unit sets a second threshold that is set according to the first threshold during a first period for determining whether to transmit the measurement result, and determines whether to transmit the measurement result using the second threshold.

2. The terminal device according to claim 1, wherein the second threshold is a value obtained by adding an offset to the first threshold.

3. The terminal device according to claim 1, wherein the control unit compares the measurement result with the first threshold value to determine whether or not to start the first period.

4. The terminal device according to claim 1, wherein the control unit controls the terminal device to stop transmitting the measurement result if the measurement result is worse than the second threshold during the first period.

5. The terminal device according to claim 1, wherein the control unit controls the terminal device to stop transmitting the measurement results if the measurement results are consecutively worse than the second threshold value during the first period.

6. The terminal device according to claim 1, wherein the control unit controls the terminal device so as not to transmit the measurement results during the second period.

7. A base station device comprising: a transmitter that transmits a first reference signal; and a receiver that receives a measurement result of a second reference signal different from the first reference signal from the terminal device when it is determined that the terminal device will transmit the measurement result using a second threshold value set according to the first threshold value during a first period for determining whether to transmit a measurement result of the reference signal.

8. A wireless communication system comprising: a terminal device that receives a reference signal and transmits a measurement result of the reference signal; and a base station device that receives the measurement result, wherein the terminal device sets a second threshold value that is set according to a first threshold value during a first period for determining whether to transmit the measurement result, and determines whether to transmit the measurement result using the second threshold value.

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