Terminal device and communication method
The terminal device's enhanced communication method with SSB request and uplink signal transmission addresses inefficiencies in next-generation wireless systems, ensuring efficient communication across multiple cell groups.
Patent Information
- Application Number
- JP2024021057
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-15
- Publication Date
- 2025-08-27
AI Technical Summary
Existing wireless communication systems face inefficiencies in terminal devices and base station devices when handling multiple cell scenarios, particularly in next-generation mobile communication systems requiring enhanced Mobile BroadBand, massive Machine Type Communication, and Ultra Reliable and Low Latency Communication.
The terminal device is equipped with radio receivers for receiving downlink signals and requesting transmission of SSB in a second cell, transmitting uplink signals containing information such as MAC control, RRC assistance, cell ID, frequency information, and transmission timing, enabling efficient communication across multiple cell groups.
This configuration allows for efficient communication between terminal and base station devices, optimizing performance in diverse cellular scenarios.
Smart Images

Figure 2025125178000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a terminal device and a communication method. [Background technology]
[0002] A wireless access method and wireless network for cellular mobile communications (hereinafter referred to as "LTE (Long The Third Generation Partnership Project (3GPP) is a non-profit organization that is working on the Third Generation Partnership Project (3GPP), also known as the "Evolved Universal Terrestrial Radio Access (EUTRA)" or "EUTRA (Evolved Universal Terrestrial Radio Access)." rd This technology is being studied in the LTE Generation Partnership Project (registered trademark). In LTE, a base station device may also be called an eNodeB (evolved NodeB), and a terminal device may also be called UE (User Equipment). LTE is a cellular communication system in which base station devices are arranged to cover multiple cell-like areas, and one base station device may manage one or multiple serving cells.
[0003] 3GPP is currently studying the next-generation wireless communication standard (NR: New Radio) to be proposed for IMT (International Mobile Telecommunication)-2020, the next-generation mobile communication system standard formulated by the International Telecommunication Union (ITU) (Non-Patent Document 1). is a single technology framework that combines eMBB (enhanced Mobile BroadBand), mMTC It is required to meet the requirements for three scenarios: (massive Machine Type Communication), and URLLC (Ultra Reliable and Low Latency Communication). [Prior art documents] [Non-patent literature]
[0004] [Non-Patent Document 1] "New SID proposal: Study on New Radio Access Technology", RP-160671, NTT DOCOMO, 3GPP TSG RAN Meeting #71, Goteborg, Sweden, 7th - 10th March, 2016. Summary of the Invention [Problem to be solved by the invention]
[0005] The present invention provides a terminal device, a base station device, and a communication method used in the terminal device or the base station device that perform communication efficiently. [Means for solving the problem]
[0006] (1) A first aspect of this embodiment of the present invention is a terminal device including a radio receiver for receiving a downlink signal in a first cell and a radio receiver for requesting transmission of an SSB in a second cell. and a radio transmission unit that transmits an uplink signal including the information.
[0007] (2) In a terminal device according to a first aspect of the present embodiment of the present invention, the uplink signal is a PUSCH in the first cell.
[0008] (3) In a terminal device according to a first aspect of this embodiment of the present invention, the uplink signal is a PRACH in the first cell.
[0009] (4) In the terminal device according to the first aspect of the present embodiment of the present invention, the information is MAC This is control information in the layer.
[0010] (5) In a terminal device according to a first aspect of the present embodiment of the present invention, the information is an RRC Assistance information in the layer.
[0011] (6) In a terminal device according to a first aspect of the present embodiment of the present invention, the information includes a cell ID of the second cell.
[0012] (7) In a terminal device according to a first aspect of the present embodiment of the present invention, the information includes frequency information of the second cell.
[0013] (8) In a terminal device according to a first aspect of this embodiment of the present invention, the information includes a transmission timing of the SSB in the second cell.
[0014] (9) A second aspect of this embodiment of the present invention is a communication method in a terminal device, which includes receiving a downlink signal in a first cell and requesting transmission of an SSB in a second cell. The mobile station transmits an uplink signal containing information. [Effects of the Invention]
[0015] According to the present invention, the terminal device can perform communication efficiently, and the base station device can perform communication efficiently. [Brief explanation of the drawings]
[0016] [Figure 1] 1 is a conceptual diagram of a wireless communication system according to an aspect of the present embodiment. [Figure 2] 10 is an example showing the relationship between Nslot symb, SCS setting μ, and CP setting according to one aspect of the present embodiment. [Figure 3] FIG. 2 is a schematic diagram illustrating an example of a resource grid in a subframe according to an aspect of the present embodiment. [Figure 4] 1 is a schematic block diagram showing a configuration of a terminal device 1 according to an aspect of the present embodiment. [Figure 5] FIG. 2 is a schematic block diagram illustrating a configuration of a base station device 3 according to one aspect of the present embodiment. [Figure 6]FIG. 10 is a diagram showing an example of a sequence of a communication method according to the present embodiment. [Figure 7] FIG. 10 is a diagram showing an example of a sequence of a communication method according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION
[0017] Hereinafter, an embodiment of the present invention will be described.
[0018] "A and / or B" may be a term that includes "A", "B", or "A and B".
[0019] FIG. 1 is a conceptual diagram of a wireless communication system according to one aspect of the present embodiment. In FIG. 1, the wireless communication system includes terminal devices 1A to 1C and a base station device 3. Hereinafter, the terminal devices 1A to 1C may also be referred to as terminal devices 1. The base station device 3 may also be referred to as a communication device, a node, a NB (NodeB), an eNB, a gNB, a network device (a core network, a gateway, etc.), etc. The terminal device 1 may include a part or all of the access point (way). The terminal device 1 may also be referred to as UE (User Equipment). The eNB is a node that provides EUTRA user plane and control plane protocol termination for one or more terminal devices 1, and in particular, connects to the fifth generation core via an NG (Next Generation) interface. An eNB connected to the network (5GC) is referred to as an ng-eNB. The gNB is a node that provides NR user plane and control plane protocol termination for one or more terminal devices 1 and is connected to the 5GC via an NG interface.
[0020] The base station device 3 may configure one or both of an MCG (Master Cell Group) and an SCG (Secondary Cell Group). The MCG includes at least a PCell (Primary Cell A serving cell group is a group of serving cells that includes at least A MCG is a group of serving cells including a PSCell (Primary Secondary Cell). A PCell may be a serving cell provided based on an initial connection. An MCG may be configured to include one or more SCells (Secondary Cells). An SCG may be configured to include one or more SCells. A PCell and a PSCell may be referred to as an SpCell (Special Cell). Configuring one CG using one SpCell and one or more SCells and performing communication may be referred to as carrier aggregation.
[0021] The MCG may be configured with one or more serving cells on EUTRA. The SCG may be configured with one or more serving cells on NR. The MCG may be configured with one or more serving cells on NR. The SCG may be configured with one or more serving cells on EUTRA. The MCG and SCG may be configured with one or more serving cells on either EUTRA or NR. Here, EUTRA refers to EUTRA RAT (Radio Access Technology) "over NR" may also mean that the NR RAT is applied.
[0022] Furthermore, the MCG may be configured by the first base station device. Furthermore, the SCG may be configured by the second base station device. That is, the PCell may be configured by the first base station device. The PSCell may be configured by the second base station device. The first base station device and the second base station device may each be the same as base station device 3.
[0023] The frame structure will be explained below.
[0024] In a wireless communication system according to an aspect of this embodiment, at least Orthogonal Frequency Division Multiplex (OFDM) is used. OFDM is a unit of time domain. An OFDM symbol contains at least one or more subcarriers. The OFDM symbol is converted into a time-continuous signal in baseband signal generation. In the downlink, at least CP-OFDM (Cyclic Prefix - Orthogonal Frequency Division Multiplexing) is used. In the link, CP-OFDM or DFT-s-OFDM (Discrete Fourier Transform) Transform, spread or Orthogonal Frequency Division Multiplex) is used. DFT-s-OFDM may be obtained by applying transform precoding to CP-OFDM.
[0025] The subcarrier spacing (SCS) is Δf=2 μ 15 kHz. For example, the SCS setting μ may be set to any of 0, 1, 2, 3, 4, and / or 5. For a certain BWP (BandWidth Part), the SCS setting μ may be given by a higher layer parameter. That is, the value of μ may be set for each BWP (each downlink BWP, each uplink BWP) regardless of downlink and / or uplink.
[0026] In the wireless communication system according to one aspect of this embodiment, a time unit T is used to express a length in the time domain. c The time unit T is used. c is T c =1 / (Δf max N f ) may be given by Δfmax may be the maximum value of the SCS supported in the wireless communication system according to one aspect of the present embodiment. max is Δf max = 480 kHz. f is N f = 4096. The constant κ can be expressed as κ = Δf max N f / (Δf ref N f,ref )=64. Δf ref may be 15kHz .N f,ref may be 2048.
[0027] The constant κ is the reference SCS and T c The constant κ may be used for the length of the subframe. The number of slots included in the subframe may be determined based at least on the constant κ. ref is the reference SCS and N f,ref is the value corresponding to the reference SCS.
[0028] The transmission of signals in the downlink and / or the transmission of signals in the uplink is configured by a frame of 10 ms. The frame is configured to include 10 subframes. The length of the subframe is 1 ms. The length of the frame may be given regardless of the SCS Δf. That is, the setting of the frame may be given regardless of the value of μ. The length of the subframe may be given regardless of the SCS Δf. That is, the setting of the subframe may be given regardless of μ.
[0029] For a given SCS setting μ, the number and index of slots included in one subframe may be given. For example, slot number n μ s ranges from 0 to N in the subframe subframe,μ slot The number of slots included in one frame and their index may be given for each SCS setting μ.μ s,f is the number of frames from 0 to N frame,μ slot -1. slot symb N OFDM symbols may be included in one slot. slot symb and / or CP(Cyclic The CP setting may be based on at least some or all of the Prefix setting. The CP configuration may be based at least on a parameter of the layer. The CP configuration may be based at least on dedicated RRC signaling. The slot number may also be referred to as a slot index.
[0030] FIG. 2 shows an N slot symb 2A is an example showing the relationship between the SCS setting μ (also referred to as the subcarrier spacing setting u) and the CP setting. For example, if the SCS setting μ is 2 and the CP setting is normal CP (NCP), then N slot symb =14, N frame,μ slot =40, N subframe,μ slot 2B, for example, when the SCS setting μ is 2 and the CP setting is the extended CP (ECP), N slot symb =12, N frame,μ slot =40, N subframe,μ slot =4.
[0031] The physical resources according to this embodiment will be described below.
[0032] An antenna port is defined by the fact that the channel through which symbols are transmitted at one antenna port can be estimated from the channel through which other symbols are transmitted at the same antenna port. If the large-scale properties of the channel through which symbols are transmitted at one antenna port can be estimated from the channel through which symbols are transmitted at another antenna port, the two antenna ports may be referred to as Quasi Co-Located (QCL). The large-scale properties may include at least the long-range properties of the channel. The large-scale properties may include some or all of the delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial Rx parameters. The first antenna port and the second antenna port may be QCLs in terms of beam parameters when a receiving beam assumed by the receiving side for the first antenna port is the same as a receiving beam assumed by the receiving side for the second antenna port. The first antenna port and the second antenna port may be QCLs in terms of beam parameters when a transmitting beam assumed by the receiving side for the first antenna port is the same as a transmitting beam assumed by the receiving side for the second antenna port. The transmission beam assumed by the receiving side for the first antenna port may be the same as the transmission beam assumed by the receiving side for the second antenna port. The terminal device 1 may assume that the two antenna ports are QCLs if the large-scale characteristics of the channel through which symbols are transmitted at one antenna port can be estimated from the channel through which symbols are transmitted at another antenna port. The fact that the two antenna ports are QCLs may mean that the two antenna ports are assumed to be QCLs.
[0033] For the SCS setting μ and the set of carriers, N size,μ grid,x N RB sc subcarriers and N subframe,μsymb Given a resource grid defined by N OFDM symbols, size,μ grid,x may denote the number of resource blocks provided for SCS configuration μ for carrier x. size,μ grid,x may denote the bandwidth of the carrier. size,μ grid,x may correspond to the value of the higher layer parameter CarrierBandwidth. Carrier x may indicate either a downlink carrier or an uplink carrier. That is, x may be either "DL" or "UL". N RB sc may represent the number of subcarriers included in one resource block. RB sc may be 12. At least one resource grid may be provided for each antenna port p and / or for each SCS setting μ and / or for each transmission direction setting. The transmission direction includes at least a downlink (DL) and an uplink (UL). Hereinafter, a parameter set including at least the antenna port p, the SCS setting μ, and some or all of the transmission direction settings may also be referred to as a first radio parameter set. That is, one resource grid may be provided for each first radio parameter set. Note that the radio parameter set may be one or more sets including one or more radio parameters (physical layer parameters or higher layer parameters).
[0034] In the downlink, a carrier included in a serving cell is called a downlink carrier (or a downlink component carrier). In the uplink, a carrier included in a serving cell is called an uplink carrier (or an uplink component carrier). The downlink component carrier and the uplink component carrier may be collectively called a component carrier (or a carrier).
[0035] The type of serving cell may be any of PCell, PSCell, and SCell. The PCell is identified by a cell ID (physical layer cell ID, physical cell ID) obtained from the SSB (Synchronization signal / Physical broadcast channel block) at the initial connection. The SCell may be a serving cell identified based at least on a dedicated RRC signaling. The SCell may be a serving cell used in carrier aggregation. The SCell may be a serving cell provided based at least on dedicated RRC signaling.
[0036] Each element in the resource grid provided for each first radio parameter set may be referred to as a resource element (RE). sc and the time domain index l sym For a given first radio parameter set, the resource elements are identified by frequency domain index k sc and the time domain index l sym The frequency domain index k is specified by sc and the time domain index l sym The resource element identified by sc , l sym ) The frequency domain index k sc is from 0 to N μ RB N RB sc It indicates either the value of -1 or N. μ RB may be the number of resource blocks given for the SCS configuration μ. μ RB is N size,μ grid,x N RB sc is the number of subcarriers contained in the resource block, and N RB sc = 12. The frequency domain index ksc is the subcarrier index k s c The time domain index l sym is the OFDM symbol index l sym One or more resource elements may correspond to a physical resource and a complex value (a complex-valued modulation symbol). One or more information bits (information bits for control information, a transport block, or higher layer parameters) may be mapped to each of the one or more resource elements corresponding to a physical resource and / or a complex value.
[0037] 3 is a schematic diagram illustrating an example of a resource grid in a subframe according to one aspect of this embodiment. In the resource grid of FIG. 3, the horizontal axis represents the time domain index l sym and the vertical axis is the frequency domain index k sc In one subframe, the frequency domain of the resource grid is N μ RB N RB sc In one subframe, the time domain of the resource grid is 14 2 μ One resource block may contain N OFDM symbols. RB sc The resource block may include subcarriers. The time domain of the resource block may correspond to one OFDM symbol. The time domain of the resource block may correspond to 14 OFDM symbols. The time domain of the resource block may correspond to one or more slots. The time domain of the resource block may correspond to one subframe.
[0038] The terminal device 1 may be instructed to transmit and receive using only a subset of the resource grid. The subset of the resource grid is also referred to as a BWP, and the BWP may be given based at least on higher layer parameters and / or part or all of the DCI. The BWP may also be referred to as a CBP (Carrier Bandwidth Part). The terminal device 1 may not be instructed to transmit and receive using the entire set of the resource grid. The terminal device 1 may be instructed to transmit and receive using some frequency resources in the resource grid. One BWP may be composed of multiple resource blocks in the frequency domain. One BWP may be composed of multiple contiguous resource blocks in the frequency domain. A BWP set for a downlink carrier may also be referred to as a downlink BWP. A BWP set for an uplink carrier may also be referred to as an uplink BWP. A BWP may be a subset of the band of a carrier (a subset of the frequency domain in a carrier).
[0039] One or more downlink BWPs may be configured for each serving cell, and one or more uplink BWPs may be configured for each serving cell.
[0040] Of one or more downlink BWPs configured for a serving cell, one downlink BWP may be configured as an active downlink BWP. A downlink BWP switch may be used to deactivate one active downlink BWP and activate inactive downlink BWPs other than the one active downlink BWP. The switching of the downlink BWP may be controlled by a BWP indication field included in the downlink control information. The switching of the downlink BWP may be controlled based on a parameter of a higher layer.
[0041] In an active downlink BWP, the DL-SCH may be received, the PDCCH may be monitored, and the PDSCH may be received.
[0042] In an inactive downlink BWP, the DL-SCH may not be received, the PDCCH may not be monitored, and CSI for the inactive downlink BWP may not be reported.
[0043] Of one or more downlink BWPs configured for the serving cell, two or more downlink BWPs may not be configured as active downlink BWPs.
[0044] Of one or more uplink BWPs configured for a serving cell, one uplink BWP may be configured as an active uplink BWP. An uplink BWP switch is used to deactivate one active uplink BWP and activate inactive uplink BWPs other than the one active uplink BWP. The switching of uplink BWPs may be controlled by a BWP indication field included in downlink control information. The switching of uplink BWPs may be controlled based on parameters of higher layers.
[0045] In an active uplink BWP, the UL-SCH may be transmitted. In an active uplink BWP, the PUCCH may be transmitted. In an active uplink BWP, the PRACH may be transmitted. In an active uplink BWP, the SRS may be transmitted.
[0046] In an inactive uplink BWP, the UL-SCH may not be transmitted. In an inactive uplink BWP, the PUCCH may not be transmitted. In an inactive uplink BWP, the PRACH may not be transmitted. In an inactive uplink BWP, the SRS may not be transmitted.
[0047] Of one or more uplink BWPs configured for one serving cell, two or more uplink BWPs may not be configured as active uplink BWPs, i.e., there only needs to be at least one active uplink BWP for the serving cell that includes uplink BWPs.
[0048] The higher layer parameters are parameters included in the higher layer signals. The higher layer signals may be RRC (Radio Resource Control) signaling or MAC CE (Medium Access Control Element). Here, the higher layer signals may be RR The RRC layer signal may be a C layer signal or a MAC layer signal. The higher layer signal may be a signal of a layer higher than the physical layer. Note that the higher layer parameters provided by the RRC layer signal may be notified to and set by the base station device 3 to the terminal device 1. The higher layer parameters provided by the RRC layer signal may be referred to as RRC parameters or RRC information elements (IEs).
[0049] The higher layer signaling may be common RRC signaling, which may have at least some or all of the following features C1 to C3: C1) Mapped to BCCH logical channel or CCCH logical channel C2) At least include the ReconfigurationWithSync information element C3) Mapped to PBCH
[0050] The ReconfigurationWithSync information element may include information indicating a commonly used configuration in the serving cell. The commonly used configuration in the serving cell may include at least a PRACH configuration. The PRACH configuration may at least indicate one or more random access preamble indices. The PRACH configuration may at least indicate a time / frequency resource of the PRACH.
[0051] The common RRC signaling may include at least common RRC parameters. The common RRC parameters are parameters that are commonly used within a serving cell (cell-specific parameters). It may also be a meter.
[0052] The higher layer signaling may be dedicated RRC signaling. The dedicated RRC signaling may have at least some or all of the following features D1 to D2: D1) Mapped to DCCH logical channel D2) ReconfigurationWithSync information element is not included
[0053] For example, MIB (Master Information Block) and SIB (System Information Block) Block) may be included in common RRC signaling. Also, a higher layer message that is mapped to a DCCH logical channel and that includes at least a ReconfigurationWithSync information element may be included in common RRC signaling. Also, a higher layer message that is mapped to a DCCH logical channel and that does not include a ReconfigurationWithSync information element may be included in dedicated RRC signaling. Note that the MIB and SIB may be collectively referred to as system information.
[0054] Note that the upper layer parameters including one or more upper layer parameters may be referred to as information elements (IEs). Furthermore, the upper layer parameters including one or more upper layer parameters and / or one or more IEs may be referred to as messages (upper layer messages, RRC messages), information blocks (IBs), or system information.
[0055] The SIB may at least indicate a time index of the SSB, the SIB may at least include information related to PRACH resources, and the SIB may at least include information related to setting up an initial connection.
[0056] The ReconfigurationWithSync information element may include at least information related to PRACH resources. The ReconfigurationWithSync information element may include at least information related to setting up an initial connection.
[0057] The dedicated RRC signaling may include at least dedicated RRC parameters. The dedicated RRC parameters are parameters that are used exclusively for the terminal device 1 (UE-specific). The dedicated RRC signaling may include at least common RRC parameters.
[0058] The common RRC parameters and dedicated RRC parameters may also be referred to as higher layer parameters.
[0059] The following describes physical channels and physical signals according to various aspects of the present embodiment.
[0060] An uplink physical channel may correspond to a set of resource elements carrying information generated in a higher layer. An uplink physical channel is a physical channel used in an uplink carrier. In a wireless communication system according to one aspect of the present embodiment, at least some or all of the following uplink physical channels are used: ·PUCCH (Physical Uplink Control CHannel) ·PUSCH (Physical Uplink Shared CHannel) ·PRACH(Physical Random Access CHannel)
[0061] The PUCCH may be used to transmit uplink control information (UCI). The uplink control information includes channel state information (CSI), scheduling requests (SR), and so on. ), and includes part or all of the HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement) information corresponding to the transport block (TB). It may also be referred to as a PDU (Medium Access Control Protocol Data Unit), DL-SCH (Downlink-Shared Channel), or PDSCH (Physical Downlink Shared Channel).
[0062] One or more types of uplink control information may be multiplexed onto the PUCCH. The multiplexed PUCCH may be transmitted. That is, multiple HARQ-ACKs may be multiplexed onto the PUCCH, multiple CSIs may be multiplexed onto the PUCCH, multiple SRs may be multiplexed onto the PUCCH, HARQ-ACKs and CSIs may be multiplexed onto the PUCCH, HARQ-ACKs and SRs may be multiplexed onto the PUCCH, or the PUCCH may be multiplexed with other types of UCI.
[0063] The HARQ-ACK information may include at least a HARQ-ACK bit corresponding to the TB. The HARQ-ACK bit may be an ACK (acknowledgement) or The HARQ-ACK information may indicate a negative-acknowledgement (NACK). The ACK may be a value indicating that decoding of the TB has been successfully completed. The NACK may be a value indicating that decoding of the TB has not been successfully completed. The HARQ-ACK information may include at least one HARQ-ACK codebook including one or more HARQ-ACK bits. The HARQ-ACK bits corresponding to one or more TBs may correspond to PDSCHs including the one or more TBs.
[0064] The HARQ-ACK bit may indicate an ACK or NACK corresponding to one Code Block Group (CBG) included in the TB. The HARQ-ACK may also be referred to as HARQ feedback, HARQ information, or HARQ control information.
[0065] The SR may be used at least to request PUSCH resources for an initial transmission. The SR may also be used to request UL-SCH resources for a new transmission. The SR bit may be used to indicate either a positive SR or a negative SR. The SR bit indicating a positive SR may also be referred to as "a positive SR is transmitted." A positive SR may indicate that a PUSCH resource for an initial transmission is requested by the terminal device 1. A positive SR may indicate that an SR is triggered by a higher layer. A positive SR may be transmitted when an SR is instructed to be transmitted by a higher layer. The SR bit indicating a negative SR may also be referred to as "a negative SR is transmitted." A negative SR may indicate that a PUSCH resource for an initial transmission is not requested by the terminal device 1. A negative SR may indicate that an SR is not triggered by a higher layer. A negative SR may be transmitted when an SR is not instructed to be transmitted by a higher layer.
[0066] The SR bit may be used to indicate either a positive SR or a negative SR for one or more SR configurations. Each of the one or more SR configurations may correspond to one or more logical channels. A positive SR for a certain SR configuration may be a positive SR for any or all of the one or more logical channels corresponding to the certain SR configuration. A negative SR may not correspond to a specific SR configuration. An indication of a negative SR may mean an indication of a negative SR for all SR configurations.
[0067] The SR setting may be a Scheduling Request ID (SR-ID). It may be given by a parameter of a higher layer.
[0068] The CSI may include at least some or all of a channel quality indicator (CQI), a precoder matrix index (PMI), and a rank index (RI). The PMI is an index related to the quality (e.g., propagation strength), the RI is an index indicating the transmission rank (or the number of transmission layers), and the PMI is an index indicating the precoder.
[0069] The CSI may be provided based at least on receiving a physical signal (e.g., CSI-RS) used at least for channel measurement. The CSI may include a value selected by the terminal device 1. The CSI may be selected by the terminal device 1 based at least on receiving a physical signal used at least for channel measurement. The channel measurement may include interference measurement. Note that the CSI-RS may be set based on the CSI-RS configuration or the SSB configuration.
[0070] A CSI report is a report of CSI. The CSI report may include CSI part 1 and / or CSI part 2. CSI part 1 may be configured to include at least a wideband channel quality information (wideband CQI), a wideband precoder matrix index (wideband PMI), and some or all of the RI. The number of bits of CSI part 1 multiplexed into the PUCCH may be a predetermined value regardless of the value of the RI of the CSI report. The number of bits of CSI part 2 multiplexed into the PUCCH may be given based on the value of the RI of the CSI report. The rank index of the CSI report may be the value of the rank index used for calculating the CSI report. The RI of the CSI information may be a value indicated by an RI field included in the CSI report.
[0071] The set of RIs allowed in a CSI report may be some or all of 1 to 8. The set of RIs allowed in a CSI report may also be based at least on a higher layer parameter RankRestriction. If the set of RIs allowed in a CSI report includes only one value, the RI of the CSI report may be the one value.
[0072] A priority may be set for a CSI report, which may be given based on at least some or all of a configuration regarding the time domain behavior (processing) of the CSI report, a content type of the CSI report, an index of the CSI report, and / or an index of a serving cell for which measurement of the CSI report is configured.
[0073] The setting regarding the time domain behavior (processing) of the CSI reporting may be a setting indicating whether the CSI reporting is performed aperiodic, semi-persistent, or quasi-static.
[0074] The content type of the CSI report may indicate whether the CSI report includes Layer 1 Reference Signals Received Power (RSRP).
[0075] Layer 1 refers to the physical layer and may be a layer that performs processing such as a physical layer processing unit, a radio transmitting unit, a transmitting unit, and / or a radio receiving unit, a receiving unit. Layers higher than Layer 1 include a MAC layer, an RRC layer, and an upper layer processing unit. For example, Layer 2 may refer to a MAC layer, an RLC layer, a PDCP layer, a MAC layer processing unit, an RLC layer processing unit, and a PDCP layer processing unit. Layer 3 may be an RRC layer and an RRC layer processing unit.
[0076] The PUSCH is used at least to transmit the TB (MAC PDU, UL-SCH). The USCH may be used to transmit at least some or all of the TB, HARQ-ACK information, CSI, and SR. The PUSCH is used at least to transmit the RAR (Msg2) in the random access procedure and / or a random access message 3 (message 3 (Msg3)) corresponding to the RAR grant. The TB may correspond to both the uplink and the downlink. That is, the PU The SCH may be used to transmit TBs for the uplink, and the PDSCH may be used to transmit TBs for the downlink.
[0077] The PRACH is used at least to transmit a random access preamble (random access message 1, message 1 (Msg1)). The PRACH is also used for the initial connection establishment procedure, handover procedure, connection re-establishment procedure, and initial access procedure. The random access preamble may be used to indicate at least some or all of the following: a PUSCH request, synchronization (timing adjustment) for PUSCH transmission, and a PUSCH resource request. The random access preamble may be used to notify the base station device 3 of an index (random access preamble index) provided by a higher layer of the terminal device 1.
[0078] The random access preamble may be generated by cyclically shifting a Zadoff-Chu sequence corresponding to a physical root sequence index u. The Zadoff-Chu sequence may be generated based on the physical root sequence index u. Multiple random access preambles may be defined in one serving cell. The random access preamble may be identified based at least on an index of the random access preamble. Different random access preambles corresponding to different indices of the random access preamble may correspond to different combinations of the physical root sequence index u and the cyclic shift. The physical root sequence index u and the cyclic shift may be determined based at least on information included in the system information. The physical root sequence index u may be an index that identifies a sequence included in the random access preamble. The random access preamble may be identified based at least on the physical root sequence index u.
[0079] In Figure 1, the following uplink physical signals are used in uplink wireless communication: The uplink physical signals may not be used to transmit information output from higher layers, but are used by the physical layer. ·UL DMRS(UpLink Demodulation Reference Signal) ·SRS(Sounding Reference Signal) ·UL PTRS(UpLink Phase Tracking Reference Signal)
[0080] The UL DMRS is related to the transmission of PUSCH and / or PUCCH. The DMRS is multiplexed with the PUSCH or PUCCH. Base station device 3 may use the UL DMRS to perform propagation path compensation for the PUSCH or PUCCH. Hereinafter, transmitting a PUSCH together with an UL DMRS associated with the PUSCH is simply referred to as transmitting a PUSCH. Hereinafter, transmitting a PUCCH together with an UL DMRS associated with the PUCCH is simply referred to as transmitting a PUCCH. The UL DMRS associated with the PUSCH is also referred to as an UL DMRS for the PUSCH. The UL DMRS associated with the PUCCH is also referred to as an UL DMRS for the PUCCH.
[0081] The SRS may not be related to the transmission of the PUSCH or the PUCCH. The base station device 3 may use the SRS to measure the channel condition. The SRS may be transmitted at the end of a subframe in an uplink slot or within a predetermined number of OFDM symbols from the end.
[0082] The UL PTRS may be a reference signal used at least for phase tracking. The UL PTRS may be associated with a UL DMRS group that includes at least the antenna ports used for one or more UL DMRSs. The association of an MRS group may be determined by the fact that the antenna port of the UL PTRS and some or all of the antenna ports included in the UL DMRS group are at least QCL. The UL DMRS group may be identified based at least on the antenna port with the smallest index among the UL DMRSs included in the UL DMRS group. The UL PTRS may be mapped to the antenna port with the smallest index among one or more antenna ports to which a single codeword is mapped. The UL PTRS may be mapped to a first layer when a single codeword is mapped to at least a first layer and a second layer. The UL PTRS may not be mapped to the second layer. The index of the antenna port to which the UL PTRS is mapped may be determined based at least on downlink control information.
[0083] 1, the following downlink physical channels are used in downlink wireless communication from the base station device 3 to the terminal device 1. The downlink physical channels are used by the physical layer to transmit information output from higher layers. ·PBCH(Physical Broadcast Channel) ·PDCCH (Physical Downlink Control Channel) ·PDSCH(Physical Downlink Shared Channel)
[0084] The PBCH is used at least to transmit the MIB and / or the PBCH payload. The PBCH payload may include at least information indicating an index related to the SSB transmission timing (SSB occasion). The PBCH payload may include information related to an SSB identifier (index). The PBCH may be transmitted based on a predetermined transmission interval. The PBCH may be transmitted at 80 millisecond (ms) intervals. The PBCH may be transmitted at 160 ms intervals. The content of the information included in the PBCH may be updated every 80 ms. Some or all of the information included in the PBCH may be updated every 160 ms. The PBCH may be configured with 288 subcarriers. The PBCH may include 2, 3, or 4 OFDM symbols. The MIB may include information related to the SSB identifier (index). The MIB may include information indicating at least a portion of the slot number, subframe number, and / or radio frame number in which the PBCH is transmitted.
[0085] The PDCCH is used at least for transmitting downlink control information (DCI). The PDCCH may be transmitted including at least DCI. The PDCCH may be transmitted including DCI. The DCI may also be referred to as a DCI format. The DCI may indicate at least either a downlink grant or an uplink grant. The DCI format used for scheduling the PDSCH may also be referred to as a downlink DCI format and / or a downlink grant. The DCI format used for scheduling the PUSCH may also be referred to as an uplink DCI format and / or an uplink grant. The downlink grant may also be referred to as a downlink assignment or a downlink allocation. The uplink DCI format includes at least one or both of DCI format 0_0 and DCI format 0_1.
[0086] The downlink DCI formats include at least one or both of DCI format 1_0 and DCI format 1_1.
[0087] DCI format 2 may include parameters used for controlling the transmission power of the PUSCH or the PUCCH. DCI format 2 includes DCI format 2_0, DCI format 2_1, DCI format 2_2, DCI format 2_3, DCI format 2_4, and DCI format 2_5. This includes some or all of DCI format 2_5, DCI format 2_6, DCI format 2_7, DCI format 2_8, and DCI format 2_9.
[0088] DCI format 2_9 may be used to activate or deactivate the cell DTX / DRX configuration of one or more serving cells for one or more UEs. I-format 2_9 is transmitted with a CRC scrambled by the NES-RNTI. DCI format 2_9 includes some or all of the following information: Block number Cell DTX / DRX indication
[0089] In various aspects of this embodiment, unless otherwise specified, the number of resource blocks (RBs) refers to the number of resource blocks in the frequency domain. Furthermore, resource block indices are assigned in ascending order from resource blocks mapped to the lower frequency domain to resource blocks mapped to the higher frequency domain. Furthermore, resource blocks are a general term for common resource blocks and physical resource blocks.
[0090] One physical channel may be mapped to one serving cell, and one physical channel may be mapped to one CBP configured for one carrier included in one serving cell.
[0091] One or more control resource sets (CORESETS) are assigned to the terminal device 1. The terminal device 1 monitors the PDCCH in one or more CORESETs.
[0092] The CORESET may indicate a time-frequency region to which one or more PDCCHs may be mapped. The CORESET may be a region in which the terminal device 1 monitors the PDCCH. The CORESET may be configured of continuous resources (localized resources). The CORESET may be configured of discontinuous resources (distributed resources).
[0093] In the frequency domain, the unit of mapping of CORESET may be a resource block (RB). For example, in the frequency domain, the unit of mapping of CORESET may be six resource blocks. That is, mapping of CORESET in the frequency domain may be performed using 6RBs×n (n is 1, 2, . . .). In the time domain, the unit of mapping of CORESET may be an OFDM symbol. For example, in the time domain, the unit of mapping of CORESET may be one OFDM symbol.
[0094] The frequency domain of the CORESET may be given based at least on higher layer signaling and / or DCI.
[0095] The time domain of the CORESET may be given based at least on higher layer signaling and / or DCI.
[0096] A certain CORESET may be a common CORESET. The common CORESET may be a CORESET that is set in common for a plurality of terminal devices 1. The common CORESET may be given based on at least some or all of the MIB, SIB, common RRC signaling, and cell ID. For example, the time resources and / or frequency resources of the CORESET that is set to monitor the PDCCH used for scheduling the SIB may be given based at least on the MIB.
[0097] A certain CORESET may be a dedicated CORESET. The dedicated CORESET may be a CORESET that is configured to be used exclusively for the terminal device 1. The dedicated CORESET may be provided based at least on dedicated RRC signaling.
[0098] The set of PDCCH candidates monitored by the terminal device 1 may be defined in terms of a search space, that is, the set of PDCCH candidates monitored by the terminal device 1 may be given by a search space.
[0099] The search space may be configured to include one or more PDCCH candidates of one or more aggregation levels (AL). The aggregation level of the PDCCH candidates may indicate the number of CCEs that constitute the PDCCH.
[0100] The terminal device 1 receives the data in a slot where DRX (Discontinuous reception) is not set. The terminal device 1 may monitor at least one or more search space sets. DRX may be provided based at least on parameters of a higher layer. The terminal device 1 may monitor at least one or more search space sets in slots where DRX is not set.
[0101] The search space set may be configured to include at least one or more search spaces. The types of the search space set include type 0 PDCCH common search space, The search space may be any of a Type 0 APDCCH common search space, a Type 1 PDCCH common search space, a Type 2 PDCCH common search space, a Type 3 PDCCH common search space, and / or a UE dedicated PDCCH search space.
[0102] The Type 0 PDCCH common search space, the Type 0 APDCCH common search space, the Type 1 PDCCH common search space, the Type 2 PDCCH common search space, and the Type 3 PDCCH common search space may also be referred to as a Common Search Space (CSS). The H search space may also be referred to as a USS (UE specific search space).
[0103] Each search space set may be associated with one control resource set, each search space set may be included in at least one control resource set, and each search space set may be given an index of the control resource set associated with that search space set.
[0104] The upper layer parameter SearchSpace specifies one or more search spaces as a set. This SearchSpace may be used to search one or more The regions may be referred to as a search region set.
[0105] The type-0 PDCCH common search space may be used at least for DCI formats with a CRC (Cyclic Redundancy Check) sequence scrambled by SI-RNTI (System Information-Radio Network Temporary Identifier). The configuration of the type-0 PDCCH common search space may be based at least on the four least significant bits (LSBs) of the upper layer parameter PDCCH-ConfigSIB1. The upper layer parameter PDCCH-ConfigSIB1 may be included in the MIB. The configuration of the type-0 PDCCH common search space may be based at least on the upper layer parameter SearchSpaceZero. The interpretation of the bits of the upper layer parameter SearchSpaceZero may be the same as the interpretation of the four least significant bits of the upper layer parameter PDCCH-ConfigSIB1. The configuration of the type-0 PDCCH common search space may be based at least on the upper layer parameter SearchSpaceSIB1. The upper layer parameter SearchSpaceSIB1 may be included in the upper layer parameter PDCCH-ConfigCommon. The PDCCH detected in the Type 0 PDCCH common search space may be used at least for scheduling the PDSCH including SIB1 and transmitted. SIB1 is a type of SIB. SIB1 may include scheduling information of SIBs other than SIB1. The terminal device 1 may receive the upper layer parameter PDCCH-ConfigCommon in EUTRA. The terminal device 1 may receive the upper layer parameter PDCCH-ConfigCommon in MCG. These common search spaces may be referred to as a Type 0 PDCCH CSS set.
[0106] The Type 0 APDCCH common search space is a Cyclic Redundancy Check (CRC) scrambled by the System Information-Radio Network Temporary Identifier (SI-RNTI). The Type 0a PDCCH common search space may be used at least for DCI formats with a SearchSpaceOtherSystemInformation (SIB1) sequence. The configuration of the Type 0a PDCCH common search space may be based at least on the higher layer parameter SearchSpaceOtherSystemInformation. The higher layer parameter SearchSpaceOtherSystemInformation may be included in SIB1. The higher layer parameter SearchSpaceOtherSystemInformation may be included in the higher layer parameter PDCCH-ConfigCommon. A PDCCH detected in the Type 0 PDCCH common search space may be used at least for scheduling a PDSCH transmitted including a SIB other than SIB1. These common search spaces may be referred to as a Type 0 APDCCH CSS set.
[0107] The Type 1 PDCCH common search space is a CRC sequence scrambled by the Random Access-Radio Network Temporary Identifier (RA-RNTI) and / or a Temporary Common-Radio Network Temporary Identifier (TC-RNTI). The RA-RNTI may be used at least for a DCI format with a CRC sequence scrambled by the RA-RNTI. The RA-RNTI may be provided based at least on the time / frequency resources of the random access preamble transmitted by the terminal device 1. The TC-RNTI may be provided by a PDSCH (also referred to as a random access message 2, message 2 (Msg2) or random access response (RAR)) scheduled by a DCI format with a CRC sequence scrambled by the RA-RNTI. The Type 1 PDCCH common search space may be provided based at least on the higher layer parameter ra-SearchSpace. The higher layer parameter ra-SearchSpace may be included in SIB1. The higher layer parameter ra-SearchSpace may be included in the higher layer parameter PDCCH-ConfigCommon. These common search spaces may be referred to as a Type 1 PDCCH CSS set.
[0108] The Type 2 PDCCH common search space may be used for DCI formats with CRC sequences scrambled by a Paging-Radio Network Temporary Identifier (P-RNTI). The P-RNTI may be used at least for transmission of DCI formats including information indicating changes in the SIB. The Type 2 PDCCH common search space may be given based at least on a higher layer parameter PagingSearchSpace. Higher Layer The parameter PagingSearchSpace may be included in SIB1. The parameter PagingSearchSpace of the higher layer may be included in the parameter PDCCH-ConfigCommon of the higher layer. These common search spaces may be referred to as a Type 2 PDCCH CSS set.
[0109] The Type 3 PDCCH common search space is for DCI formats with CRC sequences scrambled by the Cell-Radio Network Temporary Identifier (C-RNTI). The C-RNTI may be a CRC scrambled by the TC-RNTI. The type 3 PDCCH common search space may be provided based at least on a PDSCH (which may also be referred to as Random Access Message 4, Message 4 (Msg4), or Contention Resolution) scheduled by a DCI format with a sequence. The type 3 PDCCH common search space may be a search space set provided when the higher layer parameter SearchSpaceType is set to common. These common search spaces may be referred to as a type 3 PDCCH CSS set.
[0110] The UE-specific PDCCH search space may be used at least for DCI formats with CRC sequences scrambled by the C-RNTI. These UE-specific search spaces may be referred to as PDCCH sets.
[0111] When a C-RNTI is given to the terminal device 1, the Type 0 PDCCH common search space, the Type 0 APDCCH common search space, the Type 1 PDCCH common search space, and / or the Type 2 PDCCH common search space may be used at least for a DCI format with a CRC sequence scrambled with the C-RNTI.
[0112] When a C-RNTI is given to the terminal device 1, a search space set given based at least on any of the upper layer parameter PDCCH-ConfigSIB1, the upper layer parameter SearchSpaceZero, the upper layer parameter SearchSpaceSIB1, the upper layer parameter SearchSpaceOtherSystemInformation, the upper layer parameter ra-SearchSpace, the upper layer parameter PagingSearchSpace, or the upper layer parameter SearchSpace may be used at least for a DCI format with a CRC sequence scrambled with the C-RNTI.
[0113] The common CORESET may include at least one or both of a CSS and a USS. The dedicated CORESET may include at least one or both of a CSS and a USS.
[0114] The physical resources of the search area are composed of control channel elements (CCEs). Each CCE is composed of six resource element groups (REGs). An REG may be composed of one OFDM symbol of one physical resource block (PRB). In other words, an REG may be composed of 12 resource elements (REs). A PRB may also be simply referred to as a resource block (RB).
[0115] The PDSCH is used at least to transmit TB, and may also be used at least to transmit Random Access Message 2 (RAR, Msg2), and may also be used at least to transmit system information including parameters used for initial access.
[0116] In Figure 1, the following downlink physical signals are used in downlink wireless communication: The downlink physical signals may not be used to transmit information output from higher layers, but are used by the physical layer. ·Synchronization signal ·DL DMRS(DownLink DeModulation Reference Signal) ·CSI-RS(Channel State Information-Reference Signal) ·DL PTRS(DownLink Phase Tracking Reference Signal) ·TRS(Tracking Reference Signal)
[0117] The synchronization signal is used for synchronization in the frequency domain and / or the time domain of the downlink by the terminal device 1. The synchronization signal includes a PSS (Primary Synchronization Signal) and an SSS (Secondary Synchronization Signal).
[0118] An SSB (SS / PBCH block) is configured to include at least some or all of the PSS, SSS, and PBCH. The antenna ports for some or all of the PSS, SSS, and PBCH included in the SS block may be the same. Some or all of the PSS, SSS, and PBCH included in the SSB may be mapped to consecutive OFDM symbols. The CP setting for some or all of the PSS, SSS, and PBCH included in the SSB may be the same. The same SCS setting μ may be applied to some or all of the PSS, SSS, and PBCH included in the SSB.
[0119] The DL DMRS is related to the transmission of the PBCH, PDCCH, and / or PDSCH. The DL DMRS is multiplexed onto the PBCH, PDCCH, and / or PDSCH. The terminal device 1 may use the DL DMRS corresponding to the PBCH, the PDCCH, or the PDSCH to perform propagation path correction for the PBCH, the PDCCH, or the PDSCH. Hereinafter, the transmission of the PBCH and the DL DMRS associated with the PBCH together may be referred to as transmitting the PBCH. Also, the transmission of the PDCCH and the DL DMRS associated with the PDCCH together may be simply referred to as transmitting the PDCCH. Also, the transmission of the PDSCH and the DL DMRS associated with the PDSCH together may be simply referred to as transmitting the PDSCH. The DL DMRS associated with the PBCH may also be referred to as DL DMRS for the PBCH. The DL DMRS associated with the PDSCH may also be referred to as DL DMRS for the PDSCH. The DL DMRS associated with the PDCCH may also be referred to as the DL DMRS associated with the PDCCH.
[0120] The DL DMRS may be a reference signal that is individually configured for the terminal device 1. The sequence of the DL DMRS may be provided based at least on a parameter that is individually configured for the terminal device 1. The sequence of the DL DMRS may be provided based at least on a UE-specific value (e.g., C-RNTI, etc.). The DL DMRS may be transmitted individually for the PDCCH and / or the PDSCH.
[0121] The CSI-RS may be a signal at least used to calculate the CSI. The CSI-RS may also be used to measure Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ). The CSI-RS pattern assumed by the terminal device 1 may be given by at least a parameter of a higher layer.
[0122] The PTRS may be a signal that is used at least for phase noise compensation. The PTRS pattern assumed by the terminal device 1 may be based at least on higher layer parameters and / or DCI.
[0123] A DL PTRS may be associated with a DL DMRS group that includes at least the antenna ports used for one or more DL DMRSs. The association of a DL PTRS with a DL DMRS group may be such that the antenna ports of the DL PTRS and some or all of the antenna ports included in the DL DMRS group are at least QCL. The DL DMRS group may be identified based at least on the antenna port with the smallest index among the DL DMRSs included in the DL DMRS group.
[0124] The TRS is a signal used at least for time and / or frequency synchronization. The pattern of TRS assumed by the terminal device may be based at least on higher layer parameters and / or DCI.
[0125] The downlink physical channel and the downlink physical signal may also be referred to as a downlink signal. The uplink physical channel and the uplink physical signal may also be referred to as an uplink signal. The downlink signal and the uplink signal may be collectively referred to as a physical signal or a signal. The downlink physical channel and the uplink physical channel may also be collectively referred to as a physical channel. In the downlink, the physical signal may include some or all of SSB, PDCCH (CORESET), PDSCH, DL DMRS, CSI-RS, DL PTRS, and TRS. In the uplink, the physical signal may include some or all of PRACH, PUCCH, PUSCH, UL DMRS, UL PTRS, and SRS. The physical signal may be a signal other than the above-mentioned signals. That is, the physical signal may include one or more types of physical channels and / or physical signals, or may include one or more physical channels and / or physical signals.
[0126] The BCH (Broadcast CHannel), UL-SCH (Uplink-Shared CHannel), and DL-SCH (Downlink-Shared CHannel) are transport channels. The channel used in the control (MAC) layer may be called a transport channel. The unit of the transport channel used in the MAC layer may be called a TB or MAC PDU. In the MAC layer, HARQ control is performed for each TB. A TB is the unit of data that the MAC layer delivers to the physical layer. In the physical layer, a TB is a codeword. The modulation process is performed for each codeword.
[0127] The base station device 3 and the terminal device 1 exchange (transmit and receive) higher layer signals in a higher layer. For example, the base station device 3 and the terminal device 1 may transmit and receive RRC signaling (RRC messages, RRC information, RRC parameters, RRC information elements) in a radio resource control (RRC) layer. The base station device 3 and the terminal device 1 may also transmit and receive MAC CEs (Control Elements) in a MAC layer. Here, the RRC signaling The ring and / or MAC CE are also referred to as higher layer signaling.
[0128] The PUSCH and the PDSCH may be used at least for transmitting RRC signaling and / or MAC CE. Here, the RRC signaling transmitted by the base station device 3 on the PDSCH may be signaling common to multiple terminal devices 1 in the serving cell. The signaling common to multiple terminal devices 1 in the serving cell may also be referred to as common RRC signaling. The RRC signaling transmitted by the base station device 3 on the PDSCH may be signaling dedicated to a certain terminal device 1 (which may also be referred to as dedicated signaling or UE specific signaling). The signaling dedicated to a terminal device 1 may also be referred to as dedicated RRC signaling. Upper layer parameters specific to a serving cell may be transmitted using signaling common to multiple terminal devices 1 in the serving cell or signaling dedicated to a certain terminal device 1. Upper layer parameters specific to a UE may be transmitted using signaling dedicated to a certain terminal device 1.
[0129] BCCH (Broadcast Control CHannel), CCCH (Common Control CHannel), And DCCH (Dedicated Control CHannel) is a logical channel. For example, The BCCH is a channel in an upper layer used to transmit the MIB. The CCCH (Common Control CHannel) is a channel in an upper layer used to transmit information common to a plurality of terminal devices 1. Here, the CCCH is used, for example, to transmit information common to a plurality of terminal devices 1 that are connected via RRC. A DCCH (Dedicated Control CHannel) is a channel of a higher layer that is used at least for transmitting dedicated control information to the terminal device 1. Here, the DCCH may be used, for example, for a terminal device 1 that is RRC connected.
[0130] The BCCH in the logical channel may be mapped to the BCH, DL-SCH, or UL-SCH in the transport channel. The CCCH in the logical channel may be mapped to the DL-SCH or UL-SCH in the transport channel. The DCCH in the logical channel may be mapped to the DL-SCH or UL-SCH in the transport channel.
[0131] The UL-SCH in the transport channel may be mapped to the PUSCH in the physical channel, the DL-SCH in the transport channel may be mapped to the PDSCH in the physical channel, and the BCH in the transport channel may be mapped to the PBCH in the physical channel.
[0132] An example of the configuration of the terminal device 1 according to one aspect of this embodiment will be described below.
[0133] 4 is a schematic block diagram showing the configuration of a terminal device 1 according to one aspect of the present embodiment. As shown in the figure, the terminal device 1 includes a radio transmission / reception unit 10 and an upper layer processing unit 14. The radio transmission / reception unit 10 includes an antenna unit 11, an RF (Radio Frequency) unit 12, and and a part or all of a baseband unit 13. The upper layer processing unit 14 is configured to include at least a medium access control layer processing unit 15 and a part or all of a radio resource control layer processing unit 16. The radio transceiver unit 10 may also be referred to as a transmitter, a receiver, a physical layer processing unit, and / or a lower layer processing unit.
[0134] The upper layer processing unit 14 outputs uplink data (TB, UL-SCH) generated by user operation or the like to the wireless transceiver unit 10. The upper layer processing unit 14 performs processing of the MAC layer, the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the RRC layer.
[0135] The medium access control layer processing unit 15 included in the upper layer processing unit 14 performs processing of the MAC layer.
[0136] The radio resource control layer processing unit 16 included in the upper layer processing unit 14 performs processing of the RRC layer. The radio resource control layer processing unit 16 manages various setting information / parameters of its own device. The radio resource control layer processing unit 16 sets various setting information / parameters based on upper layer signals received from the base station device 3. That is, the radio resource control layer processing unit 16 sets various setting information / parameters based on information indicating the various setting information / parameters received from the base station device 3. The parameters may be upper layer parameters and / or information elements.
[0137] The wireless transceiver 10 performs physical layer processing such as modulation, demodulation, encoding, and decoding. The wireless transceiver 10 separates, demodulates, and decodes the received physical signal, and outputs the decoded information to the upper layer processing unit 14. These processes may be referred to as reception processing. The wireless transceiver 10 generates a physical signal (uplink signal) by modulating and encoding data and generating a baseband signal (converting it into a time-continuous signal), and transmits the physical signal to the base station device 3. These processes may be referred to as transmission processing.
[0138] The RF unit 12 converts the signal received via the antenna unit 11 into a baseband signal by quadrature demodulation. The RF unit 12 down-converts the analog signal and removes unnecessary frequency components from it, and outputs the processed analog signal to the baseband unit.
[0139] The baseband unit 13 converts the analog signal input from the RF unit 12 into a digital signal. The baseband unit 13 removes the portion corresponding to the CP from the converted digital signal, and performs a fast Fourier transform (FFT) on the signal from which the CP has been removed to extract a signal in the frequency domain.
[0140] The baseband unit 13 performs an inverse fast Fourier transform (IFFT) on the data to generate OFDM symbols, adds CPs to the generated OFDM symbols, generates baseband digital signals, and converts the baseband digital signals into analog signals. The baseband unit 13 outputs the converted analog signals to the RF unit 12.
[0141] The RF unit 12 uses a low-pass filter to remove unnecessary frequency components from the analog signal input from the baseband unit 13, up-converts the analog signal to a carrier frequency, and transmits it via the antenna unit 11. The RF unit 12 also amplifies power. The RF unit 12 may also have a function to control transmission power. The RF unit 12 is also referred to as a transmission power control unit.
[0142] An example of the configuration of the base station device 3 according to one aspect of this embodiment will be described below.
[0143] 5 is a schematic block diagram showing the configuration of a base station device 3 according to one aspect of the present embodiment. As shown in the figure, the base station device 3 includes a radio transmission / reception unit 30 and an upper layer processing unit 34. The radio transmission / reception unit 30 includes an antenna unit 31, an RF unit 32, and a baseband unit 33. The upper layer processing unit 34 includes a medium access control layer processing unit 35 and a radio resource control layer processing unit 36. The radio transmission / reception unit 30 is also referred to as a transmitter, a receiver, or a physical layer processing unit.
[0144] The upper layer processing unit 34 performs processing for the MAC layer, the PDCP layer, the RLC layer, and the RRC layer.
[0145] The medium access control layer processing unit 35 included in the upper layer processing unit 34 performs MAC layer processing.
[0146] The radio resource control layer processing unit 36 included in the upper layer processing unit 34 performs processing of the RRC layer. The radio resource control layer processing unit 36 generates downlink data (TB, DL-SCH) to be allocated to the PDSCH, system information, RRC messages, MAC CE, etc., or acquires them from an upper node, and outputs them to the radio transceiver unit 30. The radio resource control layer processing unit 36 also manages various setting information / parameters for each terminal device 1. The radio resource control layer processing unit 36 may set various setting information / parameters for each terminal device 1 via signals from the upper layer. That is, the radio resource control layer processing unit 36 transmits / reports information indicating the various setting information / parameters.
[0147] The basic functions of the wireless transceiver 30 are the same as those of the wireless transceiver 10, and therefore description thereof will be omitted. The wireless transceiver 30 transmits a physical signal generated in the wireless transceiver 30 to the terminal device 1 (i.e., performs transmission processing). The wireless transceiver 30 also performs reception processing on the received physical signal.
[0148] The medium access control layer processing units 15 and / or 35 may be referred to as MAC entities.
[0149] Each of the units denoted by reference numerals 10 to 16 in the terminal device 1 is configured as a circuit. Each of the units labeled 30 to 36 included in the base station device 3 may be configured as a circuit. Some or all of the units labeled 10 to 16 included in the terminal device 1 may be configured as a memory and a processor connected to the memory. Some or all of the units labeled 30 to 36 included in the base station device 3 may be configured as a memory and a processor connected to the memory. Various aspects (operations, processing) according to this embodiment may be realized (performed) in a memory included in the terminal device 1 and / or the base station device 3 and a processor connected to the memory.
[0150] In Carrier Aggregation (CA), two or more Component Carriers (CCs) are aggregated. A UE can receive signals simultaneously on one or multiple CCs, depending on its capabilities. A UE with one timing advance capability for CA may simultaneously receive and / or transmit on multiple CCs corresponding to multiple serving cells sharing the same timing advance (multiple serving cells grouped into one TAG). A UE with multiple timing advance capabilities for CA may simultaneously receive and / or transmit on multiple CCs corresponding to multiple serving cells with different timing advances (multiple serving cells grouped into multiple TAGs). A UE may simultaneously receive and / or transmit on multiple CCs corresponding to one serving cell (one serving cell). The NG-RAN ensures that each TAG contains at least one serving cell. A UE that does not support CA receives on one CC and transmits on one serving cell (one serving cell). It may be transmitted on one CC corresponding to only one serving cell in the TAG.
[0151] When CA is configured, the UE has only one RRC connection with the network. During RC connection establishment / re-establishment / handover, one serving cell is responsible for NAS mobility. provides information and RRC connection re-establishment / handover requires one serving cell to provide security. This cell is called the Primary Cell (PCell). UE Capabilities According to [RFC1111], Secondary Cells (SCells) may be configured to form a set of serving cells with a PCell. The set of serving cells configured for a UE consists of one PCell and one or more SCells. Reconfiguration, addition, and deletion of SCells is performed by RRC. In the case of Intra-NR handover and connection resumption from RRC_INACTIVE, the network may also add, remove, retain, or reconfigure SCells for use with the target PCell. When adding a new SCell, dedicated RRC signaling is used to transmit all system information required for the SCell. That is, while in connected mode, the UE does not need to obtain broadcast system information directly from the SCell.
[0152] RRC supports the states RRC_IDLE, RRC_INACTIVE, and RRC_CONNECTED. You may also use it.
[0153] In this embodiment, the wireless transceiver 10 may be configured to include a wireless receiving unit, a wireless transmitting unit, and a processing unit. For example, the wireless receiving unit may perform signal reception processing, and the wireless transmitting unit may perform signal transmission processing. For example, the processing unit may determine or set information, and the processing unit may include processing in the upper layer processing unit 14.
[0154] Fig. 6 is a diagram showing an example of the sequence of a communication method according to this embodiment. Fig. 6 shows an example in which a first cell and a second cell form a CG, and a terminal device 1 communicates with a base station device 3. For example, the first cell may be a PCell, and the second cell may be an SCell, and the second cell may be one or more SCells. The first cell may be a serving cell identified based at least on a cell ID acquired from an SSB during initial connection. The second cell may be a serving cell used in carrier aggregation.
[0155] Before S601, the terminal device 1 makes an initial connection with the base station device 3. It is assumed that the RRC connection with the station device 3 is completed (RRC_CONNECTED). In addition, before S601, the terminal device 1 is in a state where the SSB transmission is stopped. The existence of cell 2 is recognized, and the second cell is a cell that supports on-demand SSB transmission. On-demand SSB is an SSB that is transmitted when an SSB transmission is requested. The SSB transmission request is called an On-demand SSB trigger. This may also be done.
[0156] In S601, the terminal device 1 acquires first information. The first information is information transmitted in an upper layer. The first information may be notified in the upper layer or in the physical layer. The first information may also be notified in both the upper layer and the physical layer. The first information may be a value preset in the terminal device.
[0157] The first information is information for specifying a threshold. For example, the first information may be some or all of a threshold for received power (e.g., RSRP, RSRQ, SINR), a threshold for transmission rate (e.g., MCS), a threshold for QoS (e.g., a value indicating priority), a hysteresis parameter, and an offset. For example, the first information may be only the RSRQ threshold. For example, the first information may be the RSRP threshold and the RSRQ threshold. For example, the first information may be the RSRP threshold and the SINR threshold. For example, the first information may be the RSRP threshold and the hysteresis parameter.
[0158] The first information may be configured through RRC signaling, for example, a threshold and a hysteresis parameter of RSRP may be configured through RRC signaling as the first information.
[0159] A part or all of the first information may be defined in the ReportConfigNR information element. For example, the ReportConfigNR information element may include a CondTriggerConfig element, such as S An event that requests SSB transmission may be defined, and a setting value for that event may be defined. For example, in CondTriggerConfig, Thresholds (received power, transmission rate, QoS) and / or hysteresis and / or offset for this event may be defined. New parameters for this event may also be configured. For example, CondTriggerConfig-r19 may be set to request SSB transmission. Thresholds (received power, transmission rate, QoS) and / or hysteresis and / or offsets for events may be defined.
[0160] The first information may be a value pre-set in the terminal device. For example, as the first information, the RSRP threshold and the hysteresis parameter may be values pre-set in the terminal device.
[0161] The first information may also be a value set by MAC CE.
[0162] The first information may include both a value set by RRC signaling and a value pre-set in the terminal device at the same time. For example, as the first information, for the RSRP threshold, a value pre-set in the terminal device may be used, and for the hysteresis parameter, a value set by RRC signaling may be used. Also, the first information may include, at the same time, a value set by RRC signaling, a value pre-set in the terminal device, and part or all of the value set by MAC CE.
[0163] In S602, the wireless transceiver unit 10 (for example, the processing unit) of terminal device 1 uses the first information to determine whether to request the transmission of the SSB in the second cell.
[0164] In S602, when the received power in the first cell of terminal device 1 is lower than the received power threshold indicated by the first information terminal device 1 may determine to request the transmission of the SSB in the second cell. The received power in the first cell may be the measurement result of the first cell measured by terminal device 1. Let Ms be the measurement result of the first cell and Threshold be the received power threshold indicated by the first information. When Ms < Threshold, terminal device 1 may determine to request the transmission of the SSB in the second cell. For example, Ms may be the measured value of RSRP and Threshold may be the threshold of RSRP. Also, let Hys be the hysteresis parameter. When Ms + Hys < Threshold, terminal device 1 may determine to request the transmission of the SSB in the second cell cell. Also, in S602, the terminal The terminal device 1 may take into consideration the offset indicated by the first information.
[0165] In S602, the terminal device 1 determines that the transmission rate in the first cell is determined by the first information. For example, the terminal device 1 may determine to request transmission of an SSB in the second cell if the MCS in the first cell is lower than the MCS threshold indicated by the first information.
[0166] In S602, the terminal device 1 determines whether the QoS in the first cell is indicated by the first information. If the QoS is worse than a given threshold, it may decide to request transmission of the SSB in the second cell.
[0167] At S602, it is determined to request transmission of SSB in the second cell. In this case, in S603, the wireless transceiver 10 (for example, the transmitter) of the terminal device 1 The station device 3 is notified of a request to transmit an SSB in the second cell. If it is not determined to request transmission of the SSB in the second cell, in S603, the terminal device 1 notifies a request to transmit the SSB in the second cell. In addition, in S602, whether to request transmission of SSB in the second cell is determined. If this determination is not made, the terminal device does not request transmission of SSBs in the second cell.
[0168] In S603, the radio transceiver 10 (for example, a transmitter) of the terminal device 1 receives the second cell In addition, in S603, the terminal device 1 notifies the terminal device 1 of a request to transmit SSB. The second information may be included in the SSB transmission request. When an SSB transmission request is notified, the SSB transmission request may be referred to as a UE WUS (wake-up signal). The SSB transmission request may be information including an SSB transmission request and second information.
[0169] In S603, the second information is used to configure the transmission of SSB in the second cell. The second information may be any necessary information. The second information may be part or all of the cell ID of the second cell, frequency information of the second cell (e.g., carrier frequency and frequency bandwidth), and transmission timing of the SSB (e.g., transmission period, timing, timer).
[0170] In S603, the transmission request for the SSB may be transmitted on the PRACH. The transmission request may be transmitted on a PUSCH.
[0171] In S603, the transmission request for the SSB may be configured by MAC CE. In S603, the transmission request for the SSB may be configured by RRC signaling. The transmission request for the SSB may be configured by SCell activation / deactivation signaling.
[0172] In S604, the base station device 3 transmits the SSB in the second cell to the terminal device 1. In S604, the base station device 3 uses the second information to set up the second You may also configure SSB settings for the router.
[0173] In S605, the terminal device 1 receives the S The SSB in S605 may be referred to as an on-demand SSB, which is an SSB that is transmitted when a request for transmission of the SSB is made.
[0174] In S606, the terminal device 1 transmits the PDSCH in the first cell and the PDSCH in the second cell. Receive the PDSCH in the
[0175] Fig. 7 is a diagram showing an example of the sequence of a communication method according to this embodiment. Fig. 7 shows an example in which a first cell and a second cell form a CG, and a terminal device 1 communicates with a base station device 3. At this time, the first base station device covers the first cell, and the second base station device covers the second cell. The first base station device and the second base station device are connected via a backhaul. For example, the first cell may be a PCell, and the second cell may be an SCell, or the second cell may be one or more SCells. Below, the main differences between Fig. 6 and Fig. 7 will be described.
[0176] In S701, the transmitting unit of the terminal device 1 transmits the S in the second cell to the first base station device. In step S701, the terminal device 1 requests the transmission of SSB. The second information in the message may include a setting value. The SSB transmission request may be information including the SSB transmission request and the second information.
[0177] In S701, a transmission request for an SSB may be transmitted on a PRACH. The transmission request may be transmitted on a PUSCH.
[0178] In S701, the SSB transmission request may be configured by MAC CE. In S701, the SSB transmission request may be configured by RRC signaling. For example, the SSB transmission request may be configured by SCell activation / deactivation signaling.
[0179] In step S702, the first base station device requests the second base station device to transmit an SSB. In step S702, the first base station device and the second base station device are connected via a backhaul. The information may be notified accordingly.
[0180] In S703 and S704, the terminal device 1 receives the PDSCH in the first cell and the PDSCH in the second cell.
[0181] The terminal device 1 may be a terminal device including a radio receiving unit that receives a signal in a first cell and a processing unit that determines whether to request transmission of an SSB in a second cell. The first cell may be a serving cell. The second cell may be a serving cell. Alternatively, the second cell may be a cell other than the serving cell. Transmission of an SSB in the second cell may be requested via transmission of a predetermined physical channel. In this case, the process of determining whether to request transmission of an SSB in the second cell may be rephrased as a process of determining whether to transmit a predetermined physical channel, or vice versa. The predetermined physical channel may be a predetermined PRACH. Alternatively, the predetermined physical channel may be a predetermined PUCCH. Alternatively, the predetermined physical channel may be a predetermined PUSCH. The SSB transmitted by the base station device may be referred to as the first SSB, regardless of whether a request is transmitted. Request The SSB transmitted by the base station device in response to the transmission of the event may be referred to as the second SSB. The process of determining whether to request transmission of an SSB in the second cell may be referred to as processing related to a predetermined event, and the decision to request transmission of an SSB in the second cell may be rephrased as a decision to satisfy the conditions for entering the event, or vice versa. Furthermore, the decision not to request transmission of an SSB in the second cell may be rephrased as a decision to satisfy the conditions for not entering (leaving) the event, or vice versa.
[0182] A base station device that communicates with the terminal device 1 may include a radio transmitter that transmits a signal in a first cell and a radio transmitter that transmits an SSB in a second cell. The base station device may also include a receiver that receives a request transmitted from the terminal device. The base station device may also include a processor that determines whether to transmit an SSB based on the request received from the terminal device.
[0183] The signal in the first cell may include the first information. Alternatively, the terminal device 1 may store preset first information. The processing unit may determine whether to request transmission of an SSB in the second cell based on the first information. The first information may be an RRC parameter. The first information may be an RRC parameter included in an information element for configuring a measurement object. Alternatively, the first information may be an RRC parameter included in an information element for configuring a second SSB. The first information may be an offset value in the frequency of the first cell. The first information may be an offset value specific / unique to the first cell. And / or the first information may be an offset value in the frequency of the second cell, or the first information may be an offset value specific / unique to the second cell. The first information may be a hysteresis parameter for this event. The first information may be a threshold parameter for this event. Alternatively, the first information may be a combination of all or part of these parameters.
[0184] The processing unit determines whether a measurement result (for example, received power) in the first cell is equal to a threshold value. , or lower, it may be determined to request SSB transmission in the first cell. For example, a condition for entering this event may be that the result of subtracting the hysteresis parameter from the measurement result (result without offset application) in the second cell is smaller than a threshold. Alternatively, a condition for entering this event may be that the result of subtracting the hysteresis parameter from the measurement result (result without offset application) in the second cell is smaller than or equal to the threshold. For example, a condition for leaving this event may be that the result of adding the hysteresis parameter to the measurement result (result without offset application) in the second cell is larger than a threshold. Alternatively, a condition for leaving this event may be that the result of adding the hysteresis parameter to the measurement result (result without offset application) in the second cell is larger than or equal to the threshold.
[0185] Instead of the measurement result in the second cell (result without offset application), a measurement result obtained by adding an offset value to the measurement result in the second cell (result without offset application) may be used. Here, the offset value may be the offset value described above.
[0186] The processing unit may determine to request transmission of the SSB in the second cell when the transmission rate in the first cell is equal to or lower than the threshold indicated by the first information. For example, the transmission rate in the second cell (a transmission rate without an offset applied) may be determined to be equal to or lower than the threshold indicated by the first information. A condition for entering this event may be that the result of subtracting the hysteresis parameter from the transmission rate in the first cell (transmission rate to which the offset is not applied) is smaller than a threshold. Alternatively, a condition for entering this event may be that the result of subtracting the hysteresis parameter from the transmission rate in the second cell (transmission rate to which the offset is not applied) is smaller than or equal to a threshold. For example, a condition for leaving this event may be that the result of adding the hysteresis parameter to the transmission rate in the second cell (transmission rate to which the offset is not applied) is larger than a threshold. Alternatively, a condition for leaving this event may be that the result of adding the hysteresis parameter to the transmission rate in the second cell (transmission rate to which the offset is not applied) is larger than or equal to a threshold.
[0187] Instead of the transmission rate in the second cell (transmission rate to which no offset is applied), a transmission rate obtained by adding an offset value to the transmission rate in the second cell (transmission rate to which no offset is applied) may be used. Here, the offset value may be the offset value described above. The transmission rate may be an average transmission rate. Instead of the transmission rate, an index representing another data speed (for example, throughput, packet size, transport block size, modulation scheme, coding rate, etc.) may be used.
[0188] Other indices may be used instead of measurement results such as received power and transmission rate. For example, measurement results of the distance from a reference position or measurement results of elapsed time may be used instead of the measurement results and transmission rate.
[0189] The base station device 3 according to the present invention and the program running on the terminal device 1 are configured to execute a central processing unit (CPU) or the like so as to realize the functions of the above-described embodiment according to the present invention. The information handled by these devices is temporarily stored in RAM (Random Access Memory) during processing, and then written to various ROMs such as Flash ROM (Read Only Memory) or H It is stored in a DD (Hard Disk Drive) and is read by the CPU as needed, and can be modified or written. The writing is performed.
[0190] Note that the terminal device 1 and part of the base station device 3 in the above-described embodiment may be realized by a computer. In this case, a program for realizing this control function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to realize the control function.
[0191] The term "computer system" used here refers to a computer system built into the terminal device 1 or base station device 3, and includes hardware such as an OS and peripheral devices. Also, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into the computer system.
[0192] Furthermore, the term "computer-readable recording medium" may include a medium that dynamically stores a program for a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, or a medium that stores a program for a certain period of time, such as a volatile memory within a computer system that serves as a server or client in such a case. The program may also be one that realizes part of the above-mentioned functions, or one that can realize the above-mentioned functions in combination with a program already recorded in the computer system.
[0193] Furthermore, the base station device 3 in the above-described embodiment is an aggregate ( The present invention can also be realized as a group of base stations (device groups). Each of the devices constituting the device group may have some or all of the functions or functional blocks of the base station device 3 according to the above-described embodiment. The device group may have all of the functions or functional blocks of the base station device 3. Furthermore, the terminal devices 1 according to the above-described embodiment can also communicate with the base station devices as a group.
[0194] Furthermore, the base station device 3 in the above-described embodiment may be an EUTRAN (Evolved Universal Terrestrial Radio Access Network) and / or an NG-RAN (NextGen RAN, NR RAN). and / or may have some or all of the functionality of an upper node for the gNB.
[0195] Furthermore, some or all of the terminal device 1 and base station device 3 in the above-described embodiments may be realized as an LSI, which is typically an integrated circuit, or as a chipset. Each functional block of the terminal device 1 and base station device 3 may be individually formed into a chip, or some or all of them may be integrated into a chip. Furthermore, the integrated circuit method is not limited to LSI, and may be realized using a dedicated circuit or a general-purpose processor. Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology, it is also possible to use an integrated circuit based on that technology.
[0196] Furthermore, in the above-described embodiment, a terminal device is described as an example of a communication device, but the present invention is not limited to this and can also be applied to terminal devices or communication devices such as stationary or non-movable electronic devices installed indoors or outdoors, for example, AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other household appliances.
[0197] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment and includes design modifications within the scope of the gist of the present invention. Furthermore, the present invention is susceptible to various modifications within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, configurations in which elements described in the above embodiments are substituted with elements that achieve the same effect are also included. [Explanation of symbols]
[0198] 1(1A, 1B, 1C) Terminal equipment 3 Base station equipment 10, 30 Radio transmitter / receiver 11, 31 Antenna section 12, 32 RF section 13, 33 Baseband section 14, 34 Upper layer processing unit 15, 35 Medium access control layer processing unit 16, 36 Radio resource control layer processing unit
Claims
1. A terminal device, a radio receiving unit that receives a downlink signal in the first cell; A wireless device transmitting an uplink signal including information requesting transmission of an SSB in the second cell. a line transmitting unit; Terminal device.
2. The uplink signal is a PUSCH in the first cell. The terminal device according to claim 1 .
3. The uplink signal is a PRACH in the first cell. The terminal device according to claim 1 .
4. The information is control information in the MAC layer. The terminal device according to claim 1 .
5. The information is assistance information in the RRC layer. The terminal device according to claim 1 .
6. the information includes a cell ID of the second cell; The terminal device according to claim 1 .
7. the information includes frequency information of the second cell. The terminal device according to claim 1 .
8. The information includes a transmission timing of the SSB in the second cell. The terminal device according to claim 1 .
9. A communication method in a terminal device, comprising: receiving a downlink signal in a first cell; transmitting an uplink signal including information requesting transmission of the SSB in the second cell; Communication method.