Terminal, wireless communication method and base station

Abstract

The terminal according to one embodiment of the present disclosure has: a reception unit for receiving a downlink reference signal transmitted from a plurality of transmission / reception points; a control unit for determining information relating to a Doppler report on the basis of first information relating to a positive Doppler shift and / or second information relating to a negative Doppler shift, said information being obtained from the downlink reference signal; and a transmission unit for transmitting the information relating to the Doppler report. This embodiment of the present disclosure makes it possible to appropriately receive a downlink signal from a plurality of transmission points.

Description

[Technical Field]

[0001] The present disclosure relates to a terminal, a wireless communication method, and a base station in a next-generation mobile communication system. [Background technology]

[0002] In Universal Mobile Telecommunications System (UMTS) networks, Long Term Evolution (LTE) was specified with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). Also, LTE-Advanced (3GPP Rel. 10-14) was specified with the aim of achieving higher capacity and more advanced features than LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

[0003] Successor systems to LTE (e.g., 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 or later) are also being considered. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010 Summary of the Invention [Problem to be solved by the invention]

[0005] In future wireless communication systems (e.g., NR), it is expected that beams transmitted from transmission points (e.g., Remote Radio Heads (RRHs)) placed along the path of fast-moving vehicles (e.g., trains) will be used to realize wireless communication among these vehicles.

[0006] However, there has been insufficient consideration of how a terminal receives downlink signals transmitted from multiple transmission points. If such operation is not clear, it may result in a decrease in throughput.

[0007] Therefore, one object of the present disclosure is to provide a terminal, a wireless communication method, and a base station that can properly receive downlink signals from a plurality of transmission points. [Means for solving the problem]

[0008] A terminal according to an embodiment of the present disclosure includes a receiver for receiving downlink reference signals transmitted from a plurality of transmission / reception points, and a receiver for receiving first information on a positive Doppler shift and second information on a negative Doppler shift obtained from the downlink reference signals. of affection Informing based on, As a weighted average determining information regarding Doppler reporting; calculating the weighted average by using one or more of Doppler power, Doppler energy, or Doppler spread as weighting factors; The radio communication system includes a control unit and a transmission unit for transmitting information relating to the Doppler report. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, downlink signals from multiple transmission points can be properly received. [Brief explanation of the drawings]

[0010] [Figure 1] 1A and 1B are diagrams illustrating an example of communication between a mobile unit and a transmission point (eg, RRH). [Figure 2] 2A to 2C are diagrams illustrating an example of schemes 0 to 2 for SFN. [Figure 3] 3A and 3B show an example of Scheme 1. [Figure 4] 4A to 4C are diagrams illustrating an example of a NW pre-compensation scheme. [Figure 5] FIG. 5 is a diagram illustrating an example of Doppler information according to the first embodiment. [Figure 6] FIG. 6 is a diagram illustrating an example of Doppler correction according to the first embodiment. [Figure 7] FIG. 7 is a diagram showing another example of Doppler correction according to the first embodiment. [Figure 8] 8A and 8B are diagrams showing an example of Doppler information according to embodiment 3-1. [Figure 9] FIG. 9 is a diagram illustrating an example of Doppler information according to embodiment 3-2. [Figure 10] FIG. 10 is a diagram illustrating an example of Doppler information according to embodiment 3-3. [Figure 11] FIG. 11 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. [Figure 12] FIG. 12 is a diagram illustrating an example of the configuration of a base station according to an embodiment. [Figure 13] FIG. 13 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. [Figure 14] FIG. 14 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (TCI, spatial relations, QCL) In NR, it is being considered to control the reception processing (e.g., at least one of reception, demapping, demodulation, and decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, and encoding) in the UE of at least one of a signal and a channel (referred to as signal / channel) based on the transmission configuration indication state (TCI state).

[0012] The TCI state may represent that which is applied to a downlink signal / channel, and the equivalent of the TCI state which is applied to an uplink signal / channel may be expressed as a spatial relation.

[0013] The TCI state is information about the quasi-co-location (QCL) of signals / channels, and may also be called spatial reception parameters, spatial relation information, etc. The TCI state may be configured in the UE for each channel or signal.

[0014] A QCL is an index that indicates the statistical properties of a signal / channel. For example, if a signal / channel has a QCL relationship with another signal / channel, it may mean that it can be assumed that at least one of the Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter) is the same between these different signals / channels (i.e., they are QCLs with respect to at least one of these).

[0015] The spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be determined based on a spatial QCL. A QCL (or at least one element of a QCL) in the present disclosure may be replaced with an sQCL (spatial QCL).

[0016] A plurality of types (QCL types) of QCLs may be defined. For example, four QCL types A and B may be provided, each having different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may also be referred to as QCL parameters) are listed below: QCL Type A (QCL-A): Doppler shift, Doppler spread, mean delay and delay spread, QCL Type B (QCL-B): Doppler shift and Doppler spread, QCL Type C (QCL-C): Doppler shift and mean delay, · QCL Type D (QCL-D): Spatial reception parameters.

[0017] The assumption by a UE that a Control Resource Set (CORESET), channel, or reference signal has a specific QCL (e.g., QCL type D) relationship with another CORESET, channel, or reference signal may be referred to as a QCL assumption.

[0018] The UE may determine at least one of a transmit beam (Tx beam) and a receive beam (Rx beam) for a signal / channel based on the TCI condition or QCL assumption of the signal / channel.

[0019] The TCI state may be, for example, information about the QCL between the target channel (in other words, the Reference Signal (RS) for the channel) and another signal (e.g., another RS). The TCI state may be set (indicated) by higher layer signaling, physical layer signaling, or a combination thereof.

[0020] The physical layer signaling may be, for example, Downlink Control Information (DCI).

[0021] The channel for which the TCI state or spatial relationship is set (specified) may be, for example, at least one of a downlink shared channel (Physical Downlink Shared Channel (PDSCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), an uplink shared channel (Physical Uplink Shared Channel (PUSCH)), and an uplink control channel (Physical Uplink Control Channel (PUCCH)).

[0022] Furthermore, the RS that has a QCL relationship with the channel may be, for example, at least one of a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), a CSI-RS for tracking (also called a Tracking Reference Signal (TRS)), and a QCL detection reference signal (also called a QRS).

[0023] An SSB is a signal block that includes at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). An SSB may also be referred to as an SS / PBCH block.

[0024] An RS of QCL type X in a TCI state may refer to an RS that has a relationship of QCL type X with (the DMRS of) a certain channel / signal, and this RS may be called a QCL source of QCL type X in the TCI state.

[0025] (Default TCI State / Default Spatial Relationship / Default PL-RS) In Rel. 16, a PDSCH may be scheduled in a DCI with a TCI field. The TCI state for the PDSCH is indicated by the TCI field. The TCI field in DCI format 1-1 is 3 bits long, and the TCI field in DCI format 1-2 is a maximum of 3 bits long.

[0026] In RRC connected mode, if the TCI information in the first DCI (higher layer parameter tci-PresentInDCI) is set to "enabled" for a CORESET that schedules a PDSCH, the UE assumes that the TCI field is present in DCI format 1_1 of the PDCCH transmitted in that CORESET.

[0027] Furthermore, if the TCI information in the second DCI (higher layer parameter tci-PresentInDCI-1-2) for the CORESET that schedules the PDSCH is configured in the UE, the UE assumes that a TCI field with the DCI field size indicated by the TCI information in the second DCI is present in DCI format 1_2 of the PDSCH transmitted in that CORESET.

[0028] Also, in Rel. 16, a PDSCH may be scheduled by a DCI without a TCI field. The DCI format of the DCI may be DCI format 1_0 or DCI format 1_1 / 1_2 in the case where the TCI information in the DCI (the higher layer parameter tci-PresentInDCI or tci-PresentInDCI-1-2) is not configured (enabled). When a PDSCH is scheduled by a DCI without a TCI field, if the time offset between the reception of the DL DCI (the DCI that schedules the PDSCH (scheduling DCI)) and the corresponding PDSCH (the PDSCH scheduled by the DCI) is equal to or greater than a threshold (timeDurationForQCL), the UE assumes that the TCI state or QCL assumption for the PDSCH is the same as the TCI state or QCL assumption of the CORESET (e.g., the scheduling DCI).

[0029] In RRC connected mode, when the TCI information in DCI (higher layer parameters tci-PresentInDCI and tci-PresentInDCI-1-2) is set to "enabled" and when the TCI information in DCI is not set, if the time offset between the reception of a DL DCI (a DCI that schedules a PDSCH) and the corresponding PDSCH (a PDSCH scheduled by that DCI) is less than a threshold (timeDurationForQCL) (applicability condition, first condition), in the case of non-cross-carrier scheduling, the TCI state of the PDSCH (default TCI state) may be the TCI state of the lowest CORESET ID in the latest slot in the active DL BWP of that CC (of the specific UL signal). Otherwise, the TCI state of the PDSCH (default TCI state) may be the TCI state of the lowest TCI state ID of the PDSCH in the active DL BWP of the scheduled CC.

[0030] In Rel.15, separate MAC CEs are required for the activation / deactivation of PUCCH spatial relations and for the activation / deactivation of SRS spatial relations. The PUSCH spatial relations follow the SRS spatial relations.

[0031] In Rel. 16, at least one of the MAC CE for PUCCH spatial-related activation / deactivation and the MAC CE for SRS spatial-related activation / deactivation may not be used.

[0032] If neither the spatial relationship nor the PL-RS for the PUCCH is configured in FR2 (applicable condition, second condition), the default assumptions of the spatial relationship and the PL-RS for the PUCCH (default spatial relationship and default PL-RS) are applied. If neither the spatial relationship nor the PL-RS for the SRS (SRS resource for the SRS or SRS resource corresponding to the SRI in DCI format 0_1 ​​that schedules the PUSCH) is configured in FR2 (applicable condition, second condition), the default assumptions of the spatial relationship and the PL-RS for the PUSCH and SRS scheduled by DCI format 0_1 ​​(default spatial relationship and default PL-RS) are applied.

[0033] If a CORESET is configured in an active DL BWP on the CC (conditions apply), the default spatial relationship and default PL-RS may be the TCI state or QCL assumption of the CORESET with the lowest CORESET ID in the active DL BWP. If a CORESET is not configured in an active DL BWP on the CC, the default spatial relationship and default PL-RS may be the active TCI state with the lowest PDSCH ID in the active DL BWP.

[0034] In Rel.15, the spatial relationship of PUSCH scheduled by DCI format 0_0 follows the spatial relationship of the PUCCH resource with the lowest PUCCH resource ID among the active spatial relationships of PUCCH on the same CC. The network needs to update the PUCCH spatial relationships on all SCells even if no PUCCH is transmitted on the SCell.

[0035] In Rel.16, PUCCH configuration is not required for a PUSCH scheduled by DCI format 0_0. If there is no active PUCCH spatial relationship or no PUCCH resource on the active UL BWP in the CC for a PUSCH scheduled by DCI format 0_0 (applicable condition, second condition), the default spatial relationship and default PL-RS are applied to the PUSCH.

[0036] The application conditions for the default spatial relationship / default PL-RS for SRS may include setting a default beam path loss enable information element for SRS (upper layer parameter enableDefaultBeamPlForSRS) to valid. The application conditions for the default spatial relationship / default PL-RS for PUCCH may include setting a default beam path loss enable information element for PUCCH (upper layer parameter enableDefaultBeamPlForPUCCH) to valid. The application conditions for the default spatial relationship / default PL-RS for PUSCH scheduled by DCI format 0_0 may include setting a default beam path loss enable information element for PUSCH scheduled by DCI format 0_0 (upper layer parameter enableDefaultBeamPlForPUSCH0_0) to valid.

[0037] The above threshold may also be referred to as time duration for QCL, "timeDurationForQCL", "Threshold", "Threshold for offset between a DCI indicating a TCI state and a PDSCH scheduled by the DCI", "Threshold-Sched-Offset", schedule offset threshold, scheduling offset threshold, etc.

[0038] If the offset between the reception of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL, and at least one TCI state configured for the serving cell of the scheduled PDSCH includes "QCL Type D," and the UE is configured with the two default TCI enable parameter (enableTwoDefaultTCIStates-r16), and at least one TCI codepoint indicates two TCI states, the UE assumes that the DM RS port of the PDSCH or PDSCH transmission occasion of the serving cell is quasi-colocated with the RS for the QCL parameters associated with the two TCI states corresponding to the lowest codepoints among the TCI codepoints that include two different TCI states. The two default TCI enable parameter indicates that Rel. 16 operation of the two default TCI states for the PDSCH is enabled when at least one TCI codepoint maps to two TCI states.

[0039] (Multi-TRP) In NR, one or more Transmission / Reception Points (TRPs) (multi-TRPs (MTRPs)) are considered to perform DL transmission to a UE using one or more panels (multi-panels). Also, it is considered that a UE performs UL transmission to one or more TRPs using one or more panels.

[0040] Note that multiple TRPs may correspond to the same cell identifier (ID), or different cell IDs. The cell ID may be a physical cell ID or a virtual cell ID.

[0041] Multi-TRPs (e.g., TRPs #1 and #2) may be connected by ideal / non-ideal backhauls to exchange information, data, etc. Each TRP of the multi-TRP may transmit a different code word (CW) and a different layer. Non-Coherent Joint Transmission (NCJT) may be used as a form of multi-TRP transmission.

[0042] In the NCJT, for example, TRP#1 performs modulation mapping and layer mapping on a first codeword to transmit a first PDSCH using a first number of layers (e.g., two layers) with a first precoding, and TRP#2 performs modulation mapping and layer mapping on a second codeword to transmit a second number of layers (e.g., two layers) with a second precoding.

[0043] Note that multiple PDSCHs (multi-PDSCHs) that are non-coherent may be defined as partially or completely overlapping in at least one of the time and frequency domains, i.e., a first PDSCH from a first TRP and a second PDSCH from a second TRP may overlap in at least one of the time and frequency resources.

[0044] The first PDSCH and the second PDSCH may be assumed to be not quasi-co-located (Quasi-Co-Location (QCL)). Reception of multiple PDSCHs may be interpreted as simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

[0045] Multiple PDSCHs from multiple TRPs (which may also be referred to as multiple PDSCHs) may be scheduled using one DCI (single DCI, single PDCCH) (single-master mode, single-DCI based multi-TRP). Multiple PDSCHs from multiple TRPs may also be scheduled using multiple DCIs (multiple DCI, multiple PDCCHs) (multi-master mode, multi-DCI based multi-TRP).

[0046] In Ultra-Reliable and Low Latency Communications (URLLC) for multiple TRPs, it is considered that PDSCH (transport block (TB) or codeword (CW)) repetition across multiple TRPs is supported. Repetition schemes (URLLC schemes, reliability enhancement schemes, e.g., schemes 1a, 2a, 2b, 3, and 4) across multiple TRPs in the frequency domain, layer (spatial) domain, or time domain are considered to be supported. In scheme 1a, multiple PDSCHs from multiple TRPs are space division multiplexed (SDM). In schemes 2a and 2b, PDSCHs from multiple TRPs are frequency division multiplexed (FDM). In scheme 2a, the redundancy version (RV) is the same for multiple TRPs. In scheme 2b, the RVs for multiple TRPs may be the same or different. In schemes 3 and 4, multiple PDSCHs from multiple TRPs are time division multiplexed (TDM). In scheme 3, multiple PDSCHs from multiple TRPs are transmitted in one slot. In scheme 4, multiple PDSCHs from multiple TRPs are transmitted in different slots.

[0047] Such a multi-TRP scenario allows for more flexible transmission control using good quality channels.

[0048] To support intra-cell (having the same cell ID) and inter-cell (having different cell IDs) multi-TRP transmission based on multiple PDCCHs, in the RRC configuration information for linking multiple pairs of PDCCHs and PDSCHs with multiple TRPs, one control resource set (CORESET) in the PDCCH configuration information (PDCCH-Config) may correspond to one TRP.

[0049] If at least one of the following conditions 1 and 2 is satisfied, the UE may determine that the transmission is a multi-TRP transmission based on the multi-DCI transmission. In this case, the TRP may be replaced with a CORESET pool index. [Condition 1] A CORESET pool index of 1 is set. [Condition 2] Two different values ​​of the CORESET pool index (for example, 0 and 1) are set.

[0050] If the following condition is met, the UE may determine that the state is multi-TRP based on a single DCI, in which case the two TRPs may be interpreted as two TCI states indicated by the MAC CE / DCI. [conditions] "Enhanced TCI States Activation / Deactivation for UE-specific PDSCH MAC CE" is used to indicate one or two TCI states for one codepoint of the TCI field in the DCI.

[0051] The DCI for common beam instruction may be a UE-specific DCI format (e.g., DL DCI format (e.g., 1_1, 1_2), UL DCI format (e.g., 0_1, 0_2)), or may be a UE-group common DCI format.

[0052] (SFN PDCCH) For PDCCH / CORESET specified in Rel. 15, one TCI state without CORESETPoolIndex (which may also be called TRP information (TRP Info)) is set to one CORESET.

[0053] Regarding the enhancement of PDCCH / CORESET specified in Rel. 16, in multi-TRP based on multi-DCI, a CORESET pool index is set for each CORESET.

[0054] In Rel. 17 and later, the following enhancements 1 and 2 for PDCCH / CORESET are being considered.

[0055] In the case where multiple antennas (small antennas, transmitting / receiving points) with the same cell ID form a single frequency network (SFN), up to two TCI states can be set / activated for one CORESET by higher layer signaling (RRC signaling / MAC CE) (Enhancement 1). SFN contributes to at least one of improving the operation and reliability of HST (high speed train).

[0056] Furthermore, in repeated transmission of PDCCH (which may simply be called "repetition"), two PDCCH candidates in two search space sets are linked, and each search space set is associated with a corresponding CORESET (Enhancement 2). The two search space sets may be associated with the same or different CORESETs. For one CORESET, one (maximum one) TCI state can be configured / activated by higher layer signaling (RRC signaling / MAC CE).

[0057] If two search space sets are associated with different CORESETs with different TCI states, this may mean a multi-TRP repeat transmission. If two search space sets are associated with the same CORESET (CORESET with the same TCI state), this may mean a single-TRP repeat transmission.

[0058] (HST) In LTE, placement in HST (high-speed train) tunnels is difficult. Large antennas transmit both inside and outside the tunnel. For example, the transmit power of a large antenna is approximately 1 to 5 W. For handover purposes, it is important for the UE to transmit outside the tunnel before entering it. For example, the transmit power of a small antenna is approximately 250 mW. Multiple small antennas (transmitting and receiving points) with the same cell ID and a distance of 300 m form a single frequency network (SFN). All small antennas within the SFN transmit the same signal at the same time on the same PRB. It is assumed that the terminal transmits and receives to a single base station. In reality, multiple transmitting and receiving points transmit the same DL signal. When moving at high speed, transmitting and receiving points several kilometers apart form a single cell. Handover occurs when crossing cells. This reduces the frequency of handovers.

[0059] In NR, it is assumed that a beam transmitted from a transmission point (e.g., RRH) will be used to communicate with a terminal (hereinafter also referred to as UE) included in a moving object (HST (high speed train)) such as a fast-moving train. Existing systems (e.g., Rel. 15) support transmitting a unidirectional beam from the RRH to communicate with a moving object (see Figure 1A).

[0060] FIG. 1A shows a case where RRHs are installed along the moving path (or moving direction, traveling direction, or traveling path) of a moving object, and a beam is formed from each RRH in the moving direction of the moving object. An RRH that forms a beam in one direction may be called a uni-directional RRH. In the example shown in FIG. 1A, the moving object receives a negative Doppler shift (-f D ) is received.

[0061] Here, we show a case where a beam is formed in the direction of travel of the moving body, but this is not limited to this, and a beam may be formed in the opposite direction to the direction of travel, or a beam may be formed in any direction regardless of the direction of travel of the moving body.

[0062] In Rel. 16 and later, it is expected that multiple beams (e.g., two or more) will be transmitted from the RRH. For example, it is expected that beams will be formed in both the direction of travel of the moving object and the opposite direction (see Figure 1B).

[0063] 1B shows a case where RRHs are installed along the movement path of a mobile object, and beams are formed from each RRH in both the direction of travel of the mobile object and the direction opposite to the direction of travel. An RRH that forms beams in multiple directions (for example, two directions) may be called a bidirectional RRH.

[0064] In HST, the UE communicates as if it were a single TRP. In base station implementations, it is possible to transmit from multiple TRPs (same cell ID).

[0065] In the example of FIG. 1B, when two RRHs (here, RRH#1 and RRH#2) use SFN, the signal that the mobile station receives switches from a signal that has undergone a negative Doppler shift to a signal that has undergone a positive Doppler shift, which increases the power, at the midpoint between the two RRHs. In this case, the maximum Doppler shift change that requires correction is -f D From +f DThis is a change to twice that of the unidirectional RRH.

[0066] In the present disclosure, a positive Doppler shift may be interpreted as information regarding a positive Doppler shift, a Doppler shift in the positive (positive) direction, or Doppler information in the positive (positive) direction, and a negative Doppler shift may be interpreted as information regarding a negative Doppler shift, a Doppler shift in the negative (negative) direction, or Doppler information in the negative (negative) direction.

[0067] Here, as HST schemes, the following schemes 0 to 2 (HST scheme 0 to HST scheme 2) will be compared.

[0068] In scheme 0 of FIG. 2A, a tracking reference signal (TRS), a DMRS, and a PDSCH are commonly transmitted (using the same time and frequency resources) to two TRPs (RRHs) (normal SFN, transparent SFN, HST-SFN).

[0069] In scheme 0, the UE receives DL channels / signals equivalent to a single TRP, so there is one TCI state for the PDSCH.

[0070] Rel.16 specifies RRC parameters for distinguishing between transmissions using a single TRP and transmissions using SFN. When a UE reports corresponding UE capability information, the UE may distinguish between reception of a DL channel / signal using a single TRP and reception of a PDSCH assuming SFN based on the RRC parameters. On the other hand, the UE may perform transmission and reception using SFN assuming a single TRP.

[0071] In scheme 1 of Figure 2B, TRSs are transmitted TRP-specifically (using different time / frequency resources depending on the TRP). In this example, TRS1 is transmitted from TRP#1 and TRS2 is transmitted from TRP#2.

[0072] In Scheme 1, there are two TCI states for PDSCH since the UE receives DL channels / signals from each TRP using TRS from each TRP.

[0073] In scheme 2 of FIG. 2C, a TRS and a DMRS are transmitted individually for each TRP. In this example, TRS1 and DMRS1 are transmitted from TRP#1, and TRS2 and DMRS2 are transmitted from TRP#2. Compared to scheme 0, schemes 1 and 2 can suppress sudden changes in Doppler shift and appropriately estimate / guarantee the Doppler shift. Because the DMRS in scheme 2 is higher than that in scheme 1, the maximum throughput of scheme 2 is lower than that of scheme 1.

[0074] In scheme 0, the UE switches between single TRP and SFN based on higher layer signaling (RRC information elements / MAC CE).

[0075] The UE may switch between Scheme 1 / Scheme 2 / NW pre-compensation schemes based on higher layer signaling (RRC information element / MAC CE).

[0076] In Scheme 1, two TRS resources are set for the HST's forward direction and its reverse direction, respectively.

[0077] In the example of Figure 3A, the TRPs (TRP#0, #2, ...) transmitting DL signals in the direction opposite to the HST transmit the first TRS (TRS arriving before the HST) in the same time and frequency resource (SFN). The TRPs (TRP#1, #3, ...) transmitting DL signals in the direction of travel of the HST transmit the second TRS (TRS arriving after the HST) in the same time and frequency resource (SFN). The first TRS and second TRS may be transmitted / received using different frequency resources.

[0078] In the example of FIG. 3B, TRS1-1 to 1-4 are transmitted as the first TRS, and TRS2-1 to 2-4 are transmitted as the second TRS.

[0079] Considering beam operation, the first TRS is transmitted using 64 beams and 64 time resources, and the second TRS is transmitted using 64 beams and 64 time resources. The beam of the first TRS and the beam of the second TRS are considered to be equal (QCL Type D RSs are equal). By multiplexing the first TRS and the second TRS into the same time resource but different frequency resource, resource utilization efficiency can be improved.

[0080] In the example of Fig. 4A, RRHs #0-#7 are arranged along the movement path of the HST. RRHs #0-#3 and RRHs #4-#7 are connected to baseband units (BBUs) #0 and #1, respectively. Each RRH is a bidirectional RRH, and forms beams in both the direction of travel of the movement path and the opposite direction using each transmission / reception point (TRP).

[0081] In the received signal of the example of Figure 4B (single TRP (SFN) / scheme 1), when the UE receives a signal / channel (a beam in the direction of travel of the HST, a beam from behind the UE) transmitted from TRP#2n-1 (n is an integer greater than or equal to 0), a negative Doppler shift (-fD in this example) occurs. Also, when the UE receives a signal / channel (a beam in the direction opposite to the direction of travel of the HST, a beam from in front of the UE) transmitted from TRP#2n (n is an integer greater than or equal to 0), a positive Doppler shift (+fD in this example) occurs.

[0082] In Rel. 17 and later, it has been considered to correct (compensate) for Doppler shift (also referred to as Doppler compensation, pre-Doppler compensation, Doppler pre-compensation, or network (NW) pre-compensation scheme (HST NW pre-compensation scheme)) when a TRP transmits a downlink (DL) signal / channel to a UE in an HST. By performing Doppler compensation in advance when transmitting a DL signal / channel to a UE, the TRP can reduce the effect of Doppler shift when the UE receives the DL signal / channel. In this disclosure, the NW pre-compensation scheme may be a combination of Scheme 1 and Doppler shift pre-compensation by the base station.

[0083] In Rel. 17 and later, it is being considered that the TRS from each TRP will be transmitted without Doppler compensation, and the PDSCH from each TRP will be transmitted after Doppler compensation.

[0084] In the NW pre-compensation scheme, the TRPs that form beams in the direction of travel of the moving path and the TRPs that form beams in the opposite direction of travel of the moving path perform Doppler compensation before transmitting DL signals / channels to UEs within the HST. In this example, TRP#2n-1 performs positive Doppler compensation, and TRP#2n performs negative Doppler compensation to reduce the effect of Doppler shift when the UE receives the signal / channel (Figure 4C).

[0085] Note that in the situation of FIG. 4C, there may be two TCI states for the PDSCH since the UE receives DL channels / signals from each TRP using the TRS from each TRP.

[0086] Furthermore, in Rel. 17 and later, dynamic switching between single TRP and SFN using the TCI field (TCI state field) is being considered. For example, one or two TCI states are configured / indicated at each TCI code point (code point of the TCI field, DCI code point) using the RRC information element / MAC CE (e.g., Enhanced TCI States Activation / Deactivation for UE-specific PDSCH MAC CE) / DCI (TCI field). The UE may determine to receive a PDSCH with a single TRP when one TCI state is configured / indicated. Also, the UE may determine to receive a PDSCH with a multi-TRP and SFN when two TCI states are configured / indicated.

[0087] (analysis) From Rel. 17 onwards, it is being considered to support a preliminary Doppler compensation scheme in a specific frequency range (e.g., FR1), specifically whether to support Doppler reporting by the UE based on the DL RS.

[0088] In order for the NW side (for example, a base station) to perform Doppler correction, the NW needs to recognize information related to Doppler correction (for example, Doppler shift / Doppler spread).

[0089] However, there has been insufficient consideration of the Doppler estimation method for the information on the Doppler correction. For example, there has been insufficient consideration as to whether the UE should perform and report the Doppler estimation or whether the NW should perform the Doppler estimation. If this consideration is insufficient, the UE may not be able to properly perform Doppler correction or may not be able to properly receive DL signals / channels to which Doppler correction has been applied, which may result in degradation of communication performance, such as a decrease in throughput.

[0090] Therefore, the present inventors have devised an appropriate method for controlling Doppler correction.

[0091] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0092] In the present disclosure, "A / B / C" and "at least one of A, B, and C" may be read as interchangeable. In the present disclosure, cell, serving cell, CC, carrier, BWP, DL BWP, UL BWP, active DL BWP, active UL BWP, and band may be read as interchangeable. In the present disclosure, index, ID, indicator, and resource ID may be read as interchangeable. In the present disclosure, sequence, list, set, group, group, cluster, subset, etc. may be read as interchangeable. In the present disclosure, support, control, controllable, operate, and operable may be read as interchangeable.

[0093] In the present disclosure, the terms configure, activate, update, indicate, enable, specify, and select may be read interchangeably.

[0094] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof. In the present disclosure, RRC, RRC signaling, RRC parameters, higher layer, higher layer parameters, RRC information elements (IEs), RRC messages, and settings may be read interchangeably.

[0095] The MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. In the present disclosure, the MAC CE, an update command, and an activation / deactivation command may be read interchangeably.

[0096] The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI, SIB1), Other System Information (OSI), etc.

[0097] In this disclosure, the terms beam, spatial-domain filter, spatial setting, TCI state, UL TCI state, unified TCI state, unified beam, common TCI state, common beam, TCI assumption, QCL assumption, QCL parameter, spatial-domain receive filter, UE spatial-domain receive filter, UE receive beam, DL beam, DL receive beam, DL precoding, DL precoder, DL-RS, RS for QCL type D in TCI state / QCL assumption, RS for QCL type A in TCI state / QCL assumption, spatial relationship, spatial-domain transmit filter, UE spatial-domain transmit filter, UE transmit beam, UL beam, UL transmit beam, UL precoding, UL precoder, and PL-RS may be interchangeable. In this disclosure, the terms QCL type X-RS, DL-RS associated with QCL type X, DL-RS with QCL type X, source of DL-RS, SSB, CSI-RS, and SRS may be interchangeable.

[0098] In the present disclosure, the terms panel, uplink (UL) transmitting entity, TRP, spatial relationship, control resource set (CORESET), PDSCH, codeword, base station, antenna port of a certain signal (e.g., demodulation reference signal (DMRS) port), antenna port group of a certain signal (e.g., DMRS port group), group for multiplexing (e.g., code division multiplexing (CDM) group, reference signal group, CORESET group), CORESET pool, CORESET subset, CW, redundancy version (RV), layer (multi-input multi-output (MIMO) layer, transmission layer, spatial layer) may be interchangeable. Also, panel identifier (ID) and panel may be interchangeable. In the present disclosure, TRP ID and TRP may be interchangeable.

[0099] The panel may be associated with at least one of a group index of an SSB / CSI-RS group, a group index of a group-based beam report, and a group index of an SSB / CSI-RS group for group-based beam reporting.

[0100] Furthermore, a panel identifier (ID) and a panel may be interchangeable. That is, a TRP ID and a TRP, a CORESET group ID and a CORESET group, etc. may be interchangeable.

[0101] In the present disclosure, the terms TRP, transmission point, panel, DMRS port group, CORESET pool, and one of two TCI states associated with one code point in a TCI field may be read interchangeably.

[0102] In this disclosure, a single PDCCH (DCI) may be assumed to be supported when multiple TRPs utilize an ideal backhaul. Multiple PDCCHs (DCIs) may be assumed to be supported when multiple TRPs utilize a non-ideal backhaul.

[0103] The ideal backhaul may be called DMRS port group type 1, reference signal associated group type 1, antenna port group type 1, CORESET pool type 1, etc. The non-ideal backhaul may be called DMRS port group type 2, reference signal associated group type 2, antenna port group type 2, CORESET pool type 2, etc. The names are not limited to these.

[0104] In this disclosure, the terms "single TRP," "single TRP system," "single TRP transmission," and "single PDSCH" may be interchangeable. In this disclosure, the terms "multiple TRP," "multiple TRP system," "multiple TRP transmission," and "multiple PDSCH" may be interchangeable. In this disclosure, the terms "single DCI," "single PDCCH," "multiple TRP based on a single DCI," and "activating two TCI states on at least one TCI codepoint" may be interchangeable.

[0105] In the present disclosure, single TRP, channel using single TRP, channel using one TCI state / spatial relationship, no multi-TRP enabled by RRC / DCI, no multiple TCI states / spatial relationships enabled by RRC / DCI, no CORESETPoolIndex value of 1 set for any CORESET, and no codepoint in the TCI field mapped to two TCI states may be read interchangeably.

[0106] In the present disclosure, "multi-TRP," "channel using multi-TRP," "channel using multiple TCI states / spatial relationships," "multi-TRP being enabled by RRC / DCI," "multiple TCI states / spatial relationships being enabled by RRC / DCI," and "at least one of multi-TRP based on a single DCI" and "multi-TRP based on multiple DCI" may be interchangeable. In the present disclosure, "multi-TRP based on multiple DCI," and "setting a CORESET pool index (CORESETPoolIndex) value of 1 for the CORESET" may be interchangeable. In the present disclosure, "multi-TRP based on a single DCI," and "at least one code point in the TCI field is mapped to two TCI states" may be interchangeable.

[0107] In the present disclosure, TRP#1 (first TRP) may correspond to CORESET pool index = 0 or may correspond to the first of two TCI states corresponding to one code point in the TCI field. TRP#2 (second TRP) TRP#1 (first TRP) may correspond to CORESET pool index = 1 or may correspond to the second of two TCI states corresponding to one code point in the TCI field.

[0108] In the present disclosure, single DCI (sDCI), single PDCCH, multi-TRP system based on single DCI, sDCI-based MTRP, and activation of two TCI states on at least one TCI codepoint may be read interchangeably.

[0109] In the present disclosure, multi-DCI (mDCI), multi-PDCCH, multi-TRP system based on multi-DCI, mDCI-based MTRP, and setting two CORESET pool indices or CORESET pool index=1 (or a value greater than or equal to 1) may be read interchangeably.

[0110] The QCL of the present disclosure may be interchangeably read as QCL Type D.

[0111] In the present disclosure, expressions such as "TCI state A is QCL type D, which is the same as TCI state B," "TCI state A is the same as TCI state B," and "TCI state A is QCL type D with TCI state B" may be read interchangeably.

[0112] In the present disclosure, the terms DMRS, DMRS port, and antenna port may be interpreted as interchangeable.

[0113] In the present disclosure, the terms CSI-RS, NZP-CSI-RS, periodic (P)-CSI-RS, P-TRS, semi-persistent (SP)-CSI-RS, aperiodic (A)-CSI-RS, TRS, tracking CSI-RS, CSI-RS having TRS information (higher layer parameter trs-Info), NZP CSI-RS resource in an NZP CSI-RS resource set having TRS information, NZP-CSI-RS resource in an NZP-CSI-RS resource set consisting of multiple NZP-CSI-RS resources of the same antenna port, and TRS resource may be interchangeable. In the present disclosure, the terms CSI-RS resource, CSI-RS resource set, CSI-RS resource group, and information element (IE) may be interchangeable.

[0114] In the present disclosure, the code point of the DCI field 'Transmission Configuration Indication', the TCI code point, the DCI code point, and the code point of the TCI field may be read interchangeably.

[0115] In the present disclosure, the terms "single TRP" and "SFN" may be interchangeable. In the present disclosure, the terms "HST", "HST scheme", "high speed mobility scheme", "scheme 1", "scheme 2", "NW pre-compensation scheme", "HST scheme 1", "HST scheme 2", and "HST NW pre-compensation scheme" may be interchangeable.

[0116] In the present disclosure, a PDSCH / PDCCH using a single TRP may be interpreted as a PDSCH / PDCCH based on a single TRP, a single TRP PDSCH / PDCCH, etc. Also, in the present disclosure, a PDSCH / PDCCH using SFN may be interpreted as a PDSCH / PDCCH using SFN in multi-hop transmission, a PDSCH / PDCCH based on SFN, or an SFN PDSCH / PDCCH.

[0117] In the present disclosure, receiving DL signals (PDSCH / PDCCH) using SFN may mean receiving the same data (PDSCH) / control information (PDCCH) from multiple transmission / reception points using the same time / frequency resources, and / or receiving DL signals using SFN may mean receiving the same data / control information using the same time / frequency resources and / or multiple TCI states / space-domain filters / beams / QCLs.

[0118] In the present disclosure, information regarding Doppler correction (compensation), Doppler correction information, Doppler information, information regarding Doppler shift, Doppler shift, Doppler spread, Doppler shift and Doppler spread, Doppler report, and Doppler report information may be read interchangeably.

[0119] (Wireless communication method) First Embodiment The UE may measure Doppler information and may report / transmit the measured Doppler information to the NW.

[0120] In this disclosure, the measurement of Doppler information may be referred to as a Doppler measurement, and in this disclosure, the reported / transmitted Doppler information may be referred to as a Doppler report.

[0121] The UE may report the measured Doppler information using a specific UL signal / channel, for example, using some or all of CSI (L1 CSI) and / or MAC CE.

[0122] The UE may perform Doppler measurements using a specific DL RS. The specific DL RS may be, for example, at least one of CSI-RS, TRS, and SSB. The resources of the specific DL RS may be configured / instructed to the UE using higher layer signaling / physical layer signaling. The DL RS resources may be resources of a periodic DL RS. Limiting the DL RS resources to periodic DL RS resources enables measurements to be taken over a longer period / multiple times, resulting in more accurate Doppler measurements.

[0123] In the present disclosure, the Doppler information may be at least one of the following: Doppler shift, Doppler spread, (maximum / average / median) Doppler frequency, power / energy of each Doppler spread, and / or a specific outage value of the cumulative distribution function of the Doppler frequency (e.g., a specific percentage value of the cumulative distribution function), and / or a specific outage value of the cumulative distribution function of the Doppler spread.

[0124] If the UE is not configured with a resource for the DL RS for Doppler measurement, the UE may perform Doppler measurement using a resource for the DL RS determined by a specific method. Up to two TCI states may be configured as the TCI state of the PDSCH. The UE may measure multiple Doppler information (e.g., positive and negative) using the QCL source RS in each TCI state. In the present disclosure, the QCL source RS may be interchangeably read as an RS configured as an RS of a specific QCL type (e.g., QCL type A).

[0125] The DL RS resource determined by the specific method may be a periodic DL RS resource. By limiting the DL RS resource to a periodic DL RS resource, long-term / multiple measurements are possible, resulting in more accurate Doppler measurement. In this case, the UE may assume that the QCL type A RS configured as the PDSCH TCI state is only a periodic DL RS. Also, if the QCL type A RS configured as the PDSCH TCI state is not periodic, another periodic DL RS may be determined by a specific method to perform Doppler measurement. The specific method may, for example, perform Doppler measurement using another periodic DL RS that has a QCL relationship with the non-periodic QCL type A RS.

[0126] For example, when TCI state #1 and TCI state #2 are configured for PDSCH, the UE may measure Doppler information using the QCL source RS of TCI state #1 and the QCL source RS of TCI state #2, respectively.

[0127] <<How to report Doppler information>> The UE may report / transmit one or more pieces of Doppler information, which may include at least one of first Doppler information (e.g., positive Doppler information) and second Doppler information (e.g., negative Doppler information).

[0128] The UE may report the first Doppler information and the second Doppler information.

[0129] For example, when reporting Doppler shift as Doppler information, the UE may report both a positive Doppler shift and a negative Doppler shift. For example, in the case of FIG. 5, the UE may report a first value (e.g., −310 (Hz)) and a second value (e.g., +250 (Hz)).

[0130] Fig. 6 is a diagram showing an example of Doppler correction according to the first embodiment. In the example shown in Fig. 6, the UE reports Doppler information in the positive direction and Doppler information in the negative direction. Based on the reported information, the NW corrects the DL signal / channel (PDSCH) in which a beam is formed in the direction opposite to the traveling direction of the UE by -250 (Hz) and corrects the DL signal / channel (PDSCH) in which a beam is formed in the traveling direction of the UE by +310 (Hz), and transmits the DL signal / channel. The UE receives the DL signal / channel (PDSCH) to which the Doppler correction has been applied.

[0131] The UE may also report / transmit Doppler information based on positive Doppler information and negative Doppler information.

[0132] The UE may calculate / determine Doppler information based on the positive Doppler information and the negative Doppler information as an average value of the absolute value of the positive Doppler information and the absolute value of the negative Doppler information.

[0133] The average value may be calculated by equivalent (simple) averaging. For example, in the case of Figure 5, the UE may report (|-310|+|+250|) / 2 = 280 (Hz). Using equivalent averaging simplifies the UE configuration and enables appropriate Doppler correction of received signals from multiple TRPs.

[0134] Alternatively, the average value may be calculated as a weighted average. The weighted average may be calculated using the power / energy of positive and negative Doppler signals. For example, in the case of FIG. 5, the UE may report (|-310|*0.8+|+250|*1) / (0.8+1)=276 (Hz). The weighted average using power / energy enables Doppler compensation of the dominant TRP that affects the signal received by the UE, which is expected to improve performance.

[0135] The weighted average may be calculated using the Doppler spread, which is expected to improve the effectiveness of Doppler correction.

[0136] Fig. 7 is a diagram showing another example of Doppler correction according to the first embodiment. In the example shown in Fig. 7, the UE reports the average value (equivalent average, 280 (Hz) in this case) of the absolute value of the Doppler information in the positive direction and the absolute value of the Doppler information in the negative direction. Based on the reported information, the NW corrects the DL signal / channel (PDSCH) in which a beam is formed in the direction opposite to the traveling direction of the UE by -280 (Hz) and corrects the DL signal / channel (PDSCH) in which a beam is formed in the traveling direction of the UE by +280 (Hz), and transmits the DL signal / channel. The UE receives the DL signal / channel (PDSCH) to which the Doppler correction has been applied.

[0137] The UE may also report / transmit positive Doppler information or negative Doppler information. The UE may be configured / instructed to report positive Doppler information or negative Doppler information by higher layer signaling / physical layer signaling.

[0138] Alternatively, the UE may always report positive Doppler information, or may always report negative Doppler information.

[0139] The UE may also decide to report / transmit positive Doppler information or negative Doppler information based on the Doppler shift / power / energy.

[0140] For example, the UE may report / transmit Doppler information corresponding to a larger (or smaller) Doppler shift / power / energy among the positive and negative Doppler information. For example, in the case of FIG. 5, the UE may report 250 (Hz).

[0141] Note that the values ​​of Doppler shift / Doppler spread / power / energy in each drawing of this disclosure are merely examples and are not limited to these.

[0142] According to the first embodiment, it is possible to appropriately perform Doppler reporting by the UE and Doppler correction by the NW.

[0143] <Second embodiment> The second embodiment will be described with respect to the frequency band in which Doppler reporting is performed.

[0144] The first embodiment may be applied in a limited manner to a specific frequency band.

[0145] For example, the first embodiment may be limited to a Frequency Division Duplex (FDD) band. In other words, Doppler reporting may not be supported in a Time Division Duplex (TDD) band. This is because in the TDD band, the NW can obtain DL Doppler information by measuring UL RS.

[0146] Furthermore, the application of the above-described first embodiment may be reported to the NW as UE capability information for each BWP / CC / band / band combination (multiple bands) / UE. For example, when reporting the application of Doppler reporting for each band / band combination (multiple bands), the UE can report that it does not support Doppler reporting in the FDD (TDD) band.

[0147] For example, the first embodiment may be applied / operated when configured by a higher layer for each BWP / CC / band / band combination (multiple bands) / UE. For example, when the application of Doppler reporting is configured for each band / band combination (multiple bands), the UE can be configured to not perform Doppler reporting in the FDD (TDD) band but to perform Doppler reporting in the TDD (FDD) band. Also, when the application of Doppler reporting is configured for each BWP / CC, the UE may be controlled to perform Doppler reporting only in the BWP / CC specified by the network.

[0148] According to the second embodiment, it is possible to appropriately determine the frequency band in which Doppler reporting is performed.

[0149] <Third embodiment> The Doppler information may differ depending on the beam / TCI state / QCL / spatial domain filter applied to the DL signal / channel for which Doppler measurements are performed. If different beams / TCI states / QCLs / spatial domain filters are applied, the Doppler information may differ due to different propagation paths of the channel.

[0150] The Doppler information that is reported is described below.

[0151] <<Embodiment 3-1>> The UE may report Doppler information per beam / TCI state / QCL / spatial domain filter.

[0152] For example, the UE may report Doppler information for each beam (RS) using beam reporting, which may be, for example, at least one of L1 RSRP beam reporting and L1 SINR beam reporting.

[0153] Doppler information may be reported when certain higher layer parameters are set to certain values ​​(conditions).

[0154] For example, the UE may decide to report Doppler information when an upper layer parameter for reporting Doppler information is set or when an upper layer parameter for reporting Doppler information is set to enable.

[0155] 8A and 8B are diagrams illustrating an example of Doppler information according to embodiment 3-1. Fig. 8A illustrates an example of the content of L1 RSRP / SINR beam reporting when a higher layer parameter related to the reporting of Doppler information is not set to enable. When a higher layer parameter related to the reporting of Doppler information is not set to enable, the UE performs beam reporting without including Doppler information in the L1 RSRP / SINR beam reporting.

[0156] The beam report includes information (RS / beam index, RSRP / SINR value) about the beam with the best received power / reception quality (TRS#27 in FIG. 8A) and information about the beams with the second to Nth (here, N=4) received power / reception qualities (TRS#20, TRS#15, TRS#34, respectively, in FIG. 8A). Generally, the information (RSRP / SINR value) about the beams with the second to Nth received power / reception qualities is reported as a difference from the information (RSRP / SINR value) about the beam with the best received power / reception quality, but is not limited to this.

[0157] 8B shows an example of the contents of L1 RSRP / SINR beam reporting when the higher layer parameter related to the reporting of Doppler information is set to enable. When the higher layer parameter related to the reporting of Doppler information is set to enable, the UE includes Doppler information (Doppler #1 (e.g., first Doppler shift) and Doppler #2 (e.g., second Doppler shift)) corresponding to each RS index in the L1 RSRP / SINR beam reporting and sends a beam report.

[0158] In the examples shown in the drawings of the third embodiment, the Doppler report includes information on a first Doppler shift (e.g., a positive Doppler shift) and information on a second Doppler shift (e.g., a negative Doppler shift), but is not limited to this. The Doppler report may include one Doppler shift (corresponding to each RS index / each TCI state), or may include a Doppler spread in addition to the Doppler shift. When the Doppler spread is included in the Doppler report, the RS index (beam) with a smaller Doppler spread can perform Doppler correction more accurately, so the NW can perform Doppler correction more appropriately than when the Doppler spread is not included.

[0159] <<Embodiment 3-2>> The UE may report Doppler information for each beam / TCI state / QCL / spatial domain filter of the DL signal / channel (e.g., PDSCH).

[0160] For example, the UE may report Doppler information corresponding to each of multiple (eg, up to eight) active TCI states configured on the PDSCH.

[0161] Doppler information may be reported when certain higher layer parameters are set to certain values ​​(conditions).

[0162] For example, the UE may decide to report Doppler information when an upper layer parameter for reporting Doppler information is set or when an upper layer parameter for reporting Doppler information is set to enable.

[0163] The UE may report Doppler information using UCI. The priority of the UCI may be determined based on a specific rule. The priority of the UCI may be set lower than a specific UCI (e.g., HARQ-ACK / SR) and higher than UCIs other than the specific UCI. The priority of the UCI may be set higher / lower than other UCIs. The priority of the UCI may be set equal to the priority of the specific UCI (HARQ-ACK / SR / CSI).

[0164] 9 is a diagram illustrating an example of Doppler information according to embodiment 3-2. In the example illustrated in FIG. 9, the Doppler information reported by the UE includes each TCI state ID and Doppler information corresponding to the TCI state ID (Doppler #1 (e.g., first Doppler shift) and Doppler #2 (e.g., second Doppler shift)).

[0165] <<Embodiment 3-3>> The UE may report one Doppler information for multiple (eg, all) beams / TCI states / QCLs / spatial domain filters of an active DL signal / channel (eg, PDSCH).

[0166] For example, the UE may determine one piece of Doppler information based on Doppler information corresponding to each of multiple (e.g., up to eight) active TCI states set in the PDSCH, and report the one piece of Doppler information.

[0167] For example, the UE may determine one Doppler value based on an average value of the Doppler values ​​corresponding to each of a plurality of active TCI states configured for the PDSCH, which may be an equal average or a weighted average as described in the first embodiment.

[0168] Also, for example, the UE may determine / select one piece of Doppler information from among the Doppler information corresponding to each of multiple active TCI states set in the PDSCH based on the value of the Doppler spread (power / energy).

[0169] Doppler information may be reported when certain higher layer parameters are set to certain values ​​(conditions).

[0170] For example, the UE may decide to report Doppler information when an upper layer parameter for reporting Doppler information is set or when an upper layer parameter for reporting Doppler information is set to enable.

[0171] The UE may report Doppler information using UCI. The priority of the UCI may be determined based on a specific rule. The priority of the UCI may be set lower than a specific UCI (e.g., HARQ-ACK / SR) and higher than UCIs other than the specific UCI. The priority of the UCI may be set higher / lower than other UCIs. The priority of the UCI may be set equal to the priority of the specific UCI (HARQ-ACK / SR / CSI).

[0172] According to embodiment 3-3, the number of bits of information (e.g., UCI) for Doppler reporting can be reduced compared to embodiments 3-1 and 3-2. This is particularly effective when the difference in Doppler information for each TCI state is small. Furthermore, since Doppler information depends on the moving speed of the UE, the Doppler reporting described in embodiment 3-3 can also perform Doppler correction effectively.

[0173] 10 is a diagram illustrating an example of Doppler information according to embodiment 3-3. In the example illustrated in FIG. 10, the Doppler information reported by the UE includes Doppler information (Doppler #1 (e.g., a first Doppler shift) and Doppler #2 (e.g., a second Doppler shift)) corresponding to a TCI state ID, which is determined based on Doppler information corresponding to each of a plurality of (e.g., all) beams / TCI states / QCLs / spatial domain filters.

[0174] According to the third embodiment, it is possible to appropriately perform Doppler reporting by the UE and Doppler correction by the NW.

[0175] <Other embodiments> An upper layer parameter (RRC IE) / UE capability corresponding to a function (feature) in at least one of the above embodiments may be defined. The UE capability may indicate that the function is supported.

[0176] A UE configured with higher layer parameters corresponding to the function (enabling the function) may perform the function. It may also be specified that "a UE not configured with higher layer parameters corresponding to the function shall not perform the function (for example, in accordance with Rel. 15 / 16)."

[0177] A UE that reports a UE capability indicating that it supports the function may perform the function. It may also be specified that a UE that does not report a UE capability indicating that it supports the function shall not perform the function (e.g., in accordance with Rel. 15 / 16).

[0178] If the UE reports a UE capability indicating that it supports the function and the corresponding upper layer parameter is configured, the UE may perform the function. It may also be specified that "if the UE does not report a UE capability indicating that it supports the function or if the corresponding upper layer parameter is not configured, the UE shall not perform the function (e.g., in accordance with Rel. 15 / 16)."

[0179] The UE capability may indicate whether the UE supports this feature.

[0180] The UE capabilities may indicate whether or not the UE supports Doppler compensation (Doppler compensation scheme). The UE capabilities may also indicate the maximum Doppler shift / frequency that can be compensated.

[0181] The UE capabilities may indicate whether or not it supports reporting of Doppler information (Doppler reporting).

[0182] The UE capability may indicate the number of Doppler information reports, which may indicate both positive and negative Doppler information, or either positive or negative Doppler information.

[0183] The UE capabilities may indicate how many TCI states / Doppler information per beam it can report.

[0184] The UE capability information may indicate whether or not the operation of each of the above embodiments is supported.

[0185] According to the above embodiment, the UE can achieve the above functions while maintaining compatibility with existing specifications.

[0186] (wireless communication system) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0187] 11 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0188] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0189] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0190] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and the SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0191] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0192] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

[0193] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may be a frequency band higher than FR2.

[0194] Furthermore, the user terminal 20 may perform communication using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

[0195] The multiple base stations 10 may be connected by wire (for example, optical fiber conforming to the Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (for example, NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0196] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0197] The user terminal 20 may be a terminal compatible with at least one of communication methods such as LTE, LTE-A, and 5G.

[0198] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the radio communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and the uplink (UL).

[0199] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0200] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0201] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

[0202] The PDSCH transmits user data, higher layer control information, System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit Master Information Block (MIB).

[0203] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

[0204] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as an UL grant, a UL DCI, etc. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

[0205] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources to search for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor a CORESET associated with a certain search space based on the search space configuration.

[0206] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be called a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in the present disclosure may be read interchangeably.

[0207] The PUCCH / PUSCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), acknowledgement information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0208] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0209] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted as DL-RS.

[0210] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including the SS (PSS, SSS) and the PBCH (and DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as reference signals.

[0211] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0212] (base station) 12 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0213] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0214] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0215] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0216] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0217] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 1211 and an RF unit 122. The receiving unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

[0218] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0219] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0220] The transceiver 120 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0221] The transceiver 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0222] The transceiver 120 (transmission processor 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0223] The transmitting / receiving unit 120 (RF unit 122) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna .

[0224] On the other hand, the transmitting / receiving unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna .

[0225] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0226] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0227] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0228] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0229] The control unit 110 may control transmission of downlink reference signals transmitted from a plurality of transmission / reception points. The transceiver unit 120 may receive information on a Doppler report, the information being determined based on at least one of first information on a positive Doppler shift and second information on a negative Doppler shift obtained from the downlink reference signals (first embodiment).

[0230] (user terminal) 13 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transmitting / receiving antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transmitting / receiving antenna 230.

[0231] Note that this example mainly shows functional blocks of the characteristic parts of the present embodiment, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0232] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0233] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 220.

[0234] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured from a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0235] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0236] The transmitting / receiving antenna 230 can be configured as an antenna described based on common understanding in the technical field to which the present disclosure pertains, such as an array antenna.

[0237] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0238] The transceiver 220 may form at least one of a transmission beam and a reception beam using digital beamforming (for example, precoding), analog beamforming (for example, phase rotation), or the like.

[0239] The transceiver 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0240] The transceiver 220 (transmission processor 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0241] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and when transform precoding is not enabled, the transceiver unit 220 may not perform DFT processing as the transmission processing.

[0242] The transmitting / receiving unit 220 (RF unit 222) may perform modulation to a radio frequency band, filtering, amplification, etc. on the baseband signal, and transmit the radio frequency band signal via the transmitting / receiving antenna 230.

[0243] On the other hand, the transmitting / receiving unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transmitting / receiving antenna 230.

[0244] The transceiver 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

[0245] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurement, CSI measurement, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0246] The transmitting section and receiving section of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving section 220 and the transmitting / receiving antenna 230.

[0247] The transceiver 220 may receive downlink reference signals transmitted from a plurality of transmission and reception points. The controller 210 may determine information related to a Doppler report based on at least one of first information related to a positive Doppler shift and second information related to a negative Doppler shift obtained from the downlink reference signals. The transceiver 220 may transmit the information related to the Doppler report (first embodiment).

[0248] The Doppler reporting may be performed only in the Frequency Division Duplex (FDD) band (second embodiment).

[0249] The information about the Doppler report may be included in a beam report (third embodiment).

[0250] The information regarding the Doppler report may be included in the uplink control information (third embodiment).

[0251] (Hardware configuration) The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0252] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As mentioned above, the implementation method of each is not particularly limited.

[0253] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 14 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0254] In this disclosure, terms such as apparatus, circuit, device, section, unit, etc. may be read interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0255] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0256] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading predetermined software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0257] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transmission / reception unit 120 (220), etc. may be realized by the processor 1001.

[0258] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be realized in a similar manner.

[0259] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, a cache, a main memory, or the like. The memory 1002 may store executable programs (program codes), software modules, and the like for implementing a wireless communication method according to an embodiment of the present disclosure.

[0260] Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as a secondary storage device.

[0261] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0262] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0263] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0264] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using such hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0265] (Variation) Note that terms explained in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0266] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0267] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, a subcarrier spacing (SCS), a bandwidth, a symbol length, a cyclic prefix length, a transmission time interval (TTI), the number of symbols per TTI, a radio frame structure, a specific filtering process performed by a transceiver in the frequency domain, and a specific windowing process performed by a transceiver in the time domain.

[0268] A slot may be composed of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol), and may be a time unit based on numerology.

[0269] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0270] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0271] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0272] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0273] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0274] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0275] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0276] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0277] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0278] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0279] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0280] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0281] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0282] The BWP may include an UL BWP (a BWP for UL) and a DL BWP (a BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0283] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0284] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0285] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0286] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0287] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0288] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0289] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0290] Notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0291] Note that the physical layer signaling may be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be called an RRC message, such as an RRC connection setup message or an RRC connection reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0292] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0293] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0294] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0295] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0296] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0297] In the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0298] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0299] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0300] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0301] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0302] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0303] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "sidelink"). For example, terms such as uplink channel and downlink channel may be read as sidelink channel.

[0304] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0305] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME) and a Serving-Gateway (S-GW)), or a combination thereof.

[0306] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the specific order presented.

[0307] Each aspect / embodiment described in the present disclosure may be related to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE The present invention may be applied to systems that use 802.20, Ultra-Wide Band (UWB), Bluetooth (registered trademark), or other appropriate wireless communication methods, or to next-generation systems that are based on and extend these systems. Furthermore, the present invention may be applied to a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G).

[0308] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0309] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0310] The term "determining," as used in this disclosure, may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0311] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0312] Also, "decision" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "decision" may be considered to be "deciding" on some action.

[0313] Furthermore, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," or the like.

[0314] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0315] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0316] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0317] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0318] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0319] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0320] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. a receiver for receiving downlink reference signals transmitted from a plurality of transmitting and receiving points; a control unit that determines information about a Doppler report as a weighted average based on first information about a positive Doppler shift and second information about a negative Doppler shift obtained from the downlink reference signal, and calculates the weighted average by using one or more of Doppler power, Doppler energy, or Doppler spread as a weighting factor; a transmitter that transmits information related to the Doppler report.

2. 10. The terminal of claim 1, wherein the Doppler reporting is performed only in Frequency Division Duplex (FDD) bands.

3. The terminal of claim 1 , wherein the information regarding the Doppler report is included in a beam report.

4. The terminal according to claim 1 , wherein the information regarding the Doppler report is included in uplink control information.

5. receiving downlink reference signals transmitted from a plurality of transmitting and receiving points; determining information about a Doppler report as a weighted average based on first information about a positive Doppler shift and second information about a negative Doppler shift obtained from the downlink reference signal, and calculating the weighted average by using one or more of Doppler power, Doppler energy, or Doppler spread as a weighting factor; and transmitting information related to the Doppler report.

6. a control unit that controls transmission of downlink reference signals transmitted from a plurality of transmission and reception points; a receiver for receiving information on a Doppler report as a weighted average, the information being determined based on first information on a positive Doppler shift and second information on a negative Doppler shift obtained from the downlink reference signal, and the weighted average being calculated by using one or more of Doppler power, Doppler energy, or Doppler spread as weighting factors.

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