JP7519387B2 - Terminal, wireless communication method and base station - Google Patents

Description

The present disclosure relates to terminals, wireless communication methods, and base stations in next-generation mobile communication systems.

Long Term Evolution (LTE) has been specified for the Universal Mobile Telecommunications System (UMTS) network with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). In addition, LTE-Advanced (3GPP Rel. 10-14) has been specified with the aim of achieving higher capacity and greater sophistication over LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

Successor systems to LTE (also known as 5th generation mobile communication system (5G), 5G+ (plus), New Radio (NR), 3GPP Rel. 15 or later, etc.) are also being considered.

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

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 a fast-moving vehicle (e.g., a train) will be used to realize wireless communication in the vehicle.

However, there has been insufficient consideration given to how to control wireless communications in mobile devices using beams transmitted from each transmission point.

Therefore, one of the objectives of this disclosure is to provide a terminal, a wireless communication method, and a base station that can appropriately control wireless communication in a mobile body.

A terminal according to one aspect of the present disclosure has a receiving unit that receives information regarding the order of transition of a plurality of transmission configuration indicator (TCI) states that can be used for DL transmission transmitted from one or more transmission points located on a moving route, information regarding periods corresponding to the plurality of TCIs, and information regarding periods corresponding to the transmission points, and a control unit that controls reception of DL transmission transmitted from the transmission points based on the received information , wherein when at least one of the periods corresponding to the plurality of TCIs and the periods corresponding to the transmission points expires, the control unit changes the assumption of the TCI state for the DL transmission in accordance with the information regarding the order of transition of the TCI states included in the information .

According to one aspect of the present disclosure, wireless communication in a mobile body can be appropriately controlled.

1A and 1B are diagrams illustrating an example of communication between a mobile unit and a transmission point (eg, a remote radio head). 2A and 2B are diagrams illustrating an example of communication control according to the first aspect. 3A and 3B are diagrams illustrating another example of communication control according to the first aspect. 4A and 4B are diagrams illustrating another example of communication control according to the first aspect. 5A and 5B are diagrams illustrating an example of a table indicating distances between remote radio heads according to the first aspect. 6A and 6B are diagrams showing an example of the correspondence between the TCI state and the beam period according to the first aspect. FIG. 7 is a diagram showing another example of the correspondence relationship between the TCI state and the beam period according to the first aspect. 8A and 8B are diagrams illustrating an example of communication control according to the second aspect. FIG. 9 is a diagram illustrating another example of communication control according to the second aspect. FIG. 10 is a diagram illustrating another example of communication control according to the second aspect. 11A and 11B are diagrams illustrating another example of communication control according to the second aspect. 12A and 12B are diagrams illustrating another example of communication control according to the second aspect. 13A and 13B are diagrams illustrating an example of communication control according to the third aspect. FIG. 14 is a diagram showing an example of switching of a beam period (transition of a TCI state) according to the third aspect. FIG. 15 is a diagram showing another example of switching of beam periods (transition of TCI states) according to the third aspect. FIG. 16 is a diagram showing another example of switching of beam periods (transition of TCI states) according to the third aspect. FIG. 17 is a diagram showing an example of switching timing of the beam period according to the third aspect. FIG. 18 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. FIG. 19 is a diagram illustrating an example of the configuration of a base station according to an embodiment. FIG. 20 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. FIG. 21 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment.

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

1A shows a case where RRHs are installed along the moving path (or moving direction, traveling direction, or travel 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 ( _-fD ) from each RRH.

Note that, although the case shown here is one in which a beam is formed in the direction of travel of the moving object, this is not limited to the case, and a beam may also be formed in the opposite direction to the direction of travel.

In Rel. 16 and later, it is assumed that multiple (e.g., two or more) beams are transmitted from the remote radio head. For example, it is assumed that beams are formed in both the moving direction of the moving object and the opposite direction (see FIG. 1B).

1B shows a case where RRHs are installed along the moving path of a moving object, and beams are formed from each RRH in both the moving direction of the moving object and the opposite direction of the moving direction. An RRH that forms beams in multiple directions (e.g., two directions) may be called a bi-directional RRH.

In the example shown in Fig. 1B, a moving object switches from a signal that has undergone a negative Doppler shift to a signal that has undergone a positive Doppler shift with higher power at the midpoint between two remote radio heads (RRH#1 and RRH#2 in this case). In this case, the maximum Doppler shift change range that requires correction is from _-fD to + _fD , which is twice as large as that in the case of a unidirectional remote radio head.

In the future, it is desirable to support communications for mobile devices moving at speeds of 500 km/h or more using multiple remote radio heads deployed along the movement path (without the assistance of a macro cell).

On the other hand, when a mobile object is moving at high speed, it is expected that it will be difficult to properly perform beam control and handover controls.

For example, beam control in existing systems (e.g., before Rel. 15) is performed in the following steps: L1-RSRP reporting, beam notification (TCI state, spatial relation setting, or activation), and reception beam determination. However, it is difficult to perform this series of steps (e.g., TCI state notification or QCL assumption, etc.) in a short passing period using the methods of existing systems.

In addition, handover control is performed, for example, through the steps of measurement report (L3-RSRP, L3-SINR report), handover instruction, random access channel transmission, and RRC connection completion, but it is difficult to perform this series of steps in a short transit period.

(TCI, spatial relations, QCL)
In NR, it is 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 a UE of at least one of a signal and a channel (referred to as a signal/channel) based on a transmission configuration indication state (TCI state).

The TCI state may represent that which applies to the downlink signal/channel. The equivalent of the TCI state which applies to the uplink signal/channel may be expressed as a spatial relation.

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 on a per channel or per signal basis.

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 parameters (e.g., spatial Rx parameters) is the same between these different signals/channels (QCL with respect to at least one of these).

In addition, the spatial reception parameters may correspond to a reception beam (e.g., a reception analog beam) of the UE, and the beam may be identified based on a spatial QCL. The QCL (or at least one element of the QCL) in this disclosure may be read as sQCL (spatial QCL).

A plurality of types (QCL types) of QCL may be defined. For example, four QCL types A to D may be provided, each of which has different parameters (or parameter sets) that can be assumed to be the same. The parameters (which may be called QCL parameters) are as follows:
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.

The UE's assumption that a particular Control Resource Set (CORESET), channel or reference signal is in a particular QCL (e.g., QCL type D) relationship with another CORESET, channel or reference signal may be referred to as a QCL assumption.

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.

The TCI state may be, for example, information regarding the QCL between the channel of interest (in other words, the Reference Signal (RS) for that 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 of these.

In the present disclosure, higher layer signaling may be, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

The MAC signaling may be, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

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

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

In addition, 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 tracking CSI-RS (also called a tracking reference signal (TRS)), and a QCL detection reference signal (also called a QRS).

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.

The TCI state information element (RRC's "TCI-state IE") set by higher layer signaling may include one or more QCL information ("QCL-Info"). The QCL information may include at least one of information on the RS that is in a QCL relationship (RS relationship information) and information indicating the QCL type (QCL type information). The RS relationship information may include information such as an index of the RS (e.g., an SSB index, a Non-Zero-Power (NZP) CSI-RS resource identifier), an index of the cell in which the RS is located, and an index of the Bandwidth Part (BWP) in which the RS is located.

In Rel. 15 NR, both QCL type A RS and QCL type D RS, or only QCL type A RS, may be configured for a UE as at least one TCI state of the PDCCH and PDSCH.

When a TRS is configured as an RS for QCL type A, unlike a demodulation reference signal (DMRS) for a PDCCH or PDSCH, it is assumed that the same TRS is transmitted periodically over a long period of time. The UE can measure the TRS and calculate the average delay, delay spread, etc.

A UE in which the TRS is set as a QCL type A RS in the TCI state of the DMRS of the PDCCH or PDSCH can assume that the parameters of the QCL type A of the DMRS of the PDCCH or PDSCH and the TRS (average delay, delay spread, etc.) are the same, and can therefore obtain the parameters of the type A of the DMRS of the PDCCH or PDSCH (average delay, delay spread, etc.) from the measurement results of the TRS. When performing channel estimation of at least one of the PDCCH and PDSCH, the UE can perform more accurate channel estimation using the measurement results of the TRS.

A UE configured with a QCL type D RS can use the QCL type D RS to determine the UE receiving beam (spatial domain receiving filter, UE spatial domain receiving filter).

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

TCI States for PDCCH
Information regarding the QCL with the PDCCH (or a DMRS antenna port associated with the PDCCH) and a given RS may be referred to as a TCI state for the PDCCH, or the like.

The UE may determine the TCI state for a UE-specific PDCCH (CORESET) based on higher layer signaling. For example, one or more (K) TCI states may be configured for the UE by RRC signaling per CORESET.

For each CORESET, the UE may activate one of the TCI states configured by RRC signaling via a MAC CE, which may be called a TCI State Indication for UE-specific PDCCH MAC CE. The UE may monitor the CORESET based on the active TCI states corresponding to the CORESET.

TCI States for PDSCH
Information regarding the QCL with the PDSCH (or a DMRS antenna port associated with the PDSCH) and a given DL-RS may be referred to as a TCI state for the PDSCH, or the like.

The UE may be notified (configured) of M (M≧1) TCI states for the PDSCH (QCL information for M PDSCHs) by higher layer signaling. The number M of TCI states configured in the UE may be limited by at least one of the UE capability and the QCL type.

The DCI used for scheduling the PDSCH may include a predetermined field (e.g., may be called a TCI field, a TCI status field, etc.) indicating the TCI status for the PDSCH. The DCI may be used for scheduling the PDSCH of one cell and may be called, for example, DL DCI, DL assignment, DCI format 1_0, DCI format 1_1, etc.

Whether or not the TCI field is included in the DCI may be controlled by information notified from the base station to the UE. The information may be information indicating whether or not the TCI field is present in the DCI (for example, TCI presence information, TCI presence information in DCI, higher layer parameter TCI-PresentInDCI). The information may be set in the UE by, for example, higher layer signaling.

If more than eight TCI states are configured for the UE, up to eight TCI states may be activated (or specified) using a MAC CE. This MAC CE may be called a TCI States Activation/Deactivation for UE-specific PDSCH MAC CE. The value of the TCI field in the DCI may indicate one of the TCI states activated by the MAC CE.

If a UE is configured with TCI presence information set to "enabled" for a CORESET that schedules a PDSCH (a CORESET used for PDCCH transmission that schedules a PDSCH), the UE may assume that the TCI field is present in DCI format 1_1 of the PDCCH transmitted on that CORESET.

When TCI presence information is not set for a CORESET that schedules a PDSCH or the PDSCH is scheduled by DCI format 1_0, if the time offset between reception of a DL DCI (the DCI that schedules the PDSCH) and reception of the PDSCH corresponding to that DCI is greater than or equal to a threshold, the UE may assume that the TCI state or QCL assumption for the PDSCH is the same as the TCI state or QCL assumption applied to the CORESET used for the PDCCH transmission that schedules the PDSCH, in order to determine the QCL of the PDSCH antenna port.

If the TCI presence information is set to "enabled", if the TCI field in the DCI in the scheduling component carrier (CC) indicates an activated TCI state in the scheduled CC or DL BWP, and the PDSCH is scheduled by DCI format 1_1, the UE may use the TCI according to the value of the TCI field in the detected PDCCH with DCI to determine the QCL of the PDSCH antenna port. If the time offset between the reception of the DL DCI (scheduling the PDSCH) and the PDSCH corresponding to the DCI (the PDSCH scheduled by the DCI) is equal to or greater than a threshold, the UE may assume that the DM-RS port of the PDSCH of the serving cell is RS and QCL in the TCI state for the QCL type parameter given by the indicated TCI state.

In RRC connected mode, both when the TCI information in DCI (higher layer parameter TCI-PresentInDCI) 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 (DCI scheduling a PDSCH) and the corresponding PDSCH (PDSCH scheduled by that DCI) is less than a threshold, the UE may assume that the DM-RS port of the PDSCH of the serving cell has the smallest CORESET-ID in the latest slot monitored by the UE for one or more CORESETs in the active BWP of the serving cell, and is the RS and QCL for the QCL parameter used for the QCL indication of the PDCCH of the CORESET associated with the monitored search space. This RS may be referred to as the default TCI state for the PDSCH or the default QCL assumption for the PDSCH.

The time offset between reception of a DL DCI and reception of the PDSCH corresponding to that DCI may be referred to as the scheduling offset.

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.

The QCL time length may be based on the UE capabilities, e.g., on the delay required for decoding the PDCCH and for beam switching. The QCL time length may be the minimum time required for the UE to receive the PDCCH and apply the spatial QCL information received in the DCI for PDSCH processing. The QCL time length may be expressed in terms of the number of symbols per subcarrier spacing, or in terms of time (e.g., μs). The information on the QCL time length may be reported from the UE to the base station as UE capability information, or may be set in the UE by the base station using higher layer signaling.

For example, the UE may assume that the DMRS port of the PDSCH is the DL-RS and QCL based on the TCI state activated for the CORESET corresponding to the smallest CORESET-ID. The latest slot may be, for example, the slot in which a DCI scheduling the PDSCH is received.

In addition, the CORESET-ID may be an ID set by the RRC information element "ControlResourceSet" (ID for identifying the CORESET, controlResourceSetId).

If CORESET is not configured for a CC, the default TCI state may be the activated TCI state that is applicable to the PDSCH in the active DL BWP of that CC and has the lowest ID.

The inventors focused on the transition of beams (or TCI states, QCL assumptions) in a mobile object, studied communication control between a mobile object (or a UE included in the mobile object) and an RRH, and came up with the present embodiment.

Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. The configurations described in each embodiment may be applied alone or in combination.

TCI state, TCI state or QCL assumption, QCL assumption, QCL parameters, spatial domain receive filter, UE spatial domain receive filter, spatial domain filter, UE receive beam, DL receive beam, DL precoding, DL precoder, DL-RS, QCL parameters according to the DMRS port, RS of QCL type D of the TCI state or QCL assumption, RS of QCL type A of the TCI state or QCL assumption, may be read as interchangeable. RS of QCL type D, DL-RS associated with QCL type D, DL-RS having QCL type D, source of DL-RS, SSB, CSI-RS may be read as interchangeable.

In the present disclosure, the TCI state may be information about a receive beam (spatial domain receive filter) instructed (configured) for the UE (e.g., DL-RS, QCL type, cell from which the DL-RS is transmitted, etc.). The QCL assumption may be information about a receive beam (spatial domain receive filter) assumed by the UE based on the transmission or reception of an associated signal (e.g., PRACH) (e.g., DL-RS, QCL type, cell from which the DL-RS is transmitted, etc.).

In the present disclosure, a mobile object may be anything that moves at a predetermined speed or faster, and may be, for example, a train, a car, a motorcycle, a ship, etc. Furthermore, communication between a UE included in the mobile object and a transmission point (e.g., an RRH) may be performed directly between the UE and the transmission point, or may be performed between the UE and the transmission point via the mobile object (e.g., an antenna installed on the mobile object).

In addition, in this disclosure, "A/B" may be read as at least one of A and B, and "A/B/C" may be read as at least one of A, B, and C.

(First aspect)
In a first aspect, a case will be described in which a UE (e.g., a terminal included in a mobile body) controls communication with a transmission point (e.g., a remote radio head) based on information regarding beam transition.

Figure 2A shows an example of a case where a mobile object communicates with transmission points (here, RRH #1, RRH #2) arranged on the moving path. Here, a case is shown where each RRH transmits DL signals/DL channels using multiple beams. Each transmission point may be at least one of a unidirectional RRH and a bidirectional RRH.

In the following explanation, we use the example of transmitting a signal/channel from a network (e.g., RRH) to a mobile unit (e.g., UE) (DL transmission), but it can also be applied to UL transmission.

The UE may control reception of DL transmissions transmitted from a transmission point based on information regarding beam transition. Beam transition may be interchangeably interpreted as TCI state transition or QCL transition. Information regarding beam transition may be notified to the UE from a network (e.g., a base station, a transmission point) using at least one of RRC signaling and MAC CE, or may be predefined in a specification.

The information on beam transition may include at least one of information on the transition of the TCI state, a period corresponding to each beam (also called a beam period or beam time), and a period corresponding to the RRH (also called an RRH period or RRH time). The period or time may be specified in units of at least one of symbols, slots, subslots, subframes, and frames, or in units of ms or μm. The period or time may be interpreted as distance or angle.

The information regarding the transition of the TCI state (e.g., TCI#n → TCI#n+1) may be the transition/ordering/index of the TCI state. The period corresponding to the beam may be the duration/dwell-time of the beam. The period corresponding to the transmission point (RRH) may be the duration/dwell-time of the RRH.

The period corresponding to the RRH may correspond to the sum of the periods corresponding to each beam in the RRH. For example, the UE may obtain the period corresponding to the RRH from the periods corresponding to each beam. In this case, it may be unnecessary to notify or predefine the period corresponding to the RRH to the UE.

The TCI state and each beam period may be associated with each other (see FIG. 2B). FIG. 2B is a diagram showing an example of a table in which the TCI state and each beam period are associated with the index of each beam period (e.g., t0, t1, t2, t3, t4, t5).

Each beam period index (t0, t1, t2, t3, t4, t5) may correspond to a different beam. In addition, depending on the movement of the mobile unit (UE), the beam period index may transition (or switch, change, modify, or update) in the order of t0, t1, t2, t3, t4, and t5.

Here, the transition is shown to be in the order of TCI state #0 (t0), TCI state #1 (t1), TCI state #2 (t2), TCI state #3 (t3), TCI state #4 (t4), and TCI state #5 (t5). In communication with the transmission points (RRHs #1 and #2), the UE may control reception of DL transmissions by assuming that the TCI state (or QCL) transitions according to the period corresponding to each beam (see Figures 3A and B).

The upper diagram in Figure 3A corresponds to an image diagram that takes into account the geographic domain in communication with RRH #1, and the lower diagram shows the transition of the TCI state in the time direction. Here, slot units (slot boundaries) are shown in the time direction, but other time units (e.g., at least one of symbols, subslots, subframes, frames, ms, and μm) may also be used. Figure 3B shows an example of a table showing the beam transitions to be set (or the association between TCI states and beam periods).

When each beam period expires, the UE may update the TCI state (or QCL assumption) based on the configured TCI state transition order. For example, in communication with RRH #1, the UE may assume TCI state #0 in the corresponding beam period (here, 4), and switch to TCI state #1 after the beam period expires to control reception of DL signals/channels.

In communication with the transmission point (RRH#1), the UE may determine the first beam period index (e.g., t0) or the start point of the period corresponding to the beam based on a predetermined condition or method. For example, the UE (or the mobile unit) may determine based on a current position obtained from a GPS or the like, or based on a predetermined signal (e.g., a reference signal) transmitted from the transmission point.

In this way, the UE can control communication with the transmission point based on information regarding beam transition, allowing appropriate communication even when the mobile object is moving at high speed.

<Variation 1-1>
The duration corresponding to the beam may be a ratio (e.g., duration ratio, dwell ratio, dwell time ratio) of the duration in which each beam is used at the transmission point (see Fig. 4A, B). The UE may control reception of DL transmissions (e.g., determine the assumed TCI state or QCL) based on the ratio of the duration in which each beam is used at each transmission point.

The beam period may not be signaled or configured to the UE. In this case, the UE may blindly change (or switch, change, update) the TCI state based on the transition order of the TCI state (or QCL).

<Variation 1-2>
The period corresponding to the RRH may be information (e.g., Distance/duration) on the distance or duration between the RRHs (e.g., RRH#1 and RRH#2). For example, information on the average distance or average duration between adjacent RRHs (e.g., RRH#n and RRH#n+1) may be notified to the UE (see FIG. 5A). Here, the case where the average distance between each RRH is indicated by 3 is shown.

Alternatively, information regarding the distance or period between each RRH (e.g., between adjacent RRHs) may be notified or configured to the UE (see FIG. 5B). When RRH#1 to RRH#6 are arranged on the moving route, the UE may control reception of DL transmission in each RRH based on information regarding the distance or period between each RRH. Reception of DL transmission in each RRH may apply the method described above.

The UE can appropriately communicate with each RRH by grasping the relationship between the RRHs. Note that information regarding the distance or period between the RRHs may be notified from the base station to the UE using at least one of RRC signaling and MAC CE, or may be predefined in the specifications.

<Variation 1-3>
The UE may be controlled to detect (e.g., blind detect) a predetermined TCI state from multiple TCI states in a certain beam period. For example, when the TCI state corresponding to the beam period t is #i, the UE may detect the TCI state #i and other TCI states in the beam period t. The other TCI states may be one or more TCI states that transition before or after the TCI state #i. The TCI state #i and the other TCI states may be included in a predetermined window (e.g., a blind detection window).

Figure 6A shows a case where, in beam period t1, a TCI state is blindly detected from TCI state #1 corresponding to t1 and TCI states #0 and #2 which transition before and after TCI state #1. In other words, this corresponds to a case where the blind detection window includes TCI states #1, #2, and #3. The range or size of the blind detection window (e.g., row, index, range or size of TCI states) may be set by the network or may be predefined.

This allows communication with the transmission point based on the appropriate TCI state or QCL assumption, even if there is a discrepancy between the beam period (or TCI state) assumed by the UE and its actual position.

<Variation 1-4>
A plurality of TCI states may correspond to each beam period (see FIG. 6B). Here, a case where two or more TCI states correspond to each beam period is shown. The UE may detect (e.g., blindly detect) a predetermined (e.g., one) TCI state from the plurality of TCI states in each beam period.

For example, the UE determines one TCI state from TCI states #0 and #1 in beam period t0. The determination of the TCI state may be based on the reception conditions (e.g., reception power, etc.) when each TCI state is used.

<Variation 1-5>
When multiple TCI states correspond to each beam period (see FIG. 6B), the UE may detect one or more TCI states depending on the terminal capability (UE capability). For example, when the UE supports the capability of simultaneously receiving DL transmissions transmitted from multiple transmission points (multi-panel simultaneous reception), the UE may detect two TCI states and perform reception processing.

In this way, by matching multiple TCI states to a beam period, DL transmissions from multiple transmission points can be received simultaneously.

<Variation 1-6>
A plurality of candidates for the TCI state corresponding to each beam period may be set, and the TCI state to be actually applied (or assumed) may be determined based on a predetermined condition (see FIG. 7). Here, a case is shown in which two TCI states are set for each beam period. For example, a plurality of transition lists of the TCI state corresponding to each beam period may be set, and the list to be actually used may be selected from the plurality of lists.

The TCI status list may be configured from the network to the UE using at least one of higher layer signaling and MAC CE, or may be predefined in the specification. The UE may determine one list from among multiple lists based on downlink control information (DCI) or PDCCH. For example, the TCI list may be specified using a new bit field or an existing bit field included in the DCI. Alternatively, the TCI list may be selected based on the position and resources (e.g., CCE/PRB/RE index) of the DCI detected by the UE.

When a TCI state (or TCI state list) is specified using a new bit field of DCI, the size (e.g., number of bits) of the new bit field may be determined based on the number of TCI states (or TCI state lists) to be set.

If one TCI state corresponds to each beam period, the new bit field is not required (it is not included in the DCI). If multiple TCI states correspond to at least one of the beam periods, the new bit field may be included in the DCI.

In this way, by selecting and using one TCI list from multiple TCI state lists, it is possible to flexibly set the beam (or TCI state) to be used for communication with each RRH.

(Second Aspect)
In a second aspect, the UE determines separately for each type or type of signal/channel the TCI state to be applied or assumed for receiving DL transmissions.

In the following description, the TCI state to be applied or assumed for receiving the PDCCH and the TCI state to be applied or assumed for receiving the PDSCH are determined separately. Note that any of the following methods may be applied to other DL signals/channels.

<TCI state of PDCCH>
The UE may determine the TCI state of the PDCCH by applying the above-mentioned first aspect (e.g., beam transition information). The beam transition information may be set separately for each control resource set (CORESET). Alternatively, the beam transition information may be set commonly for a plurality of control resource sets (CORESET).

<PDSCH TCI Status>
The UE may determine the TCI status of the PDSCH using a method different from that of the PDCCH.

For example, multiple TCI states may be set for each beam period (see Figures 8A and B). Here, a case is shown in which a TCI state list is set separately for each beam period. Each TCI state list may include multiple (here, 8 (3 bits)) TCI states. The size of the TCI state list set for each beam period (e.g., the number of TCI states included in the list) may be the same or different.

The TCI state list (or one or more TCI states) corresponding to each beam period may be configured in the UE using at least one of higher layer signaling and MAC CE, or may be defined in the specification. The TCI state may be configured separately for each beam period, or activation/deactivation of the TCI state configured for each beam period may be notified.

In addition, when a TCI status list is set for one beam period, the TCI status list may be applied to other beam periods (e.g., all beam periods).

One or more TCI states included in the TCI state list may be associated with a code point (e.g., a bit value) of a specific field of the DCI. When a specific field is included in the received DCI (or PDCCH), the UE may determine the TCI state to be applied in the beam period for receiving the PDSCH based on the code point of the specific field.

Whether or not a specific field is included in the DCI may be notified by higher layer signaling. For example, if a higher layer parameter (e.g., tciPresentInDCI) is configured to indicate that a specific field (e.g., a TCI field) is included in the DCI, the UE may assume that the TCI status of the PDSCH is notified in the specific field of the DCI.

If a higher layer parameter (e.g., tciPresentInDCI) is not configured indicating that a specified field (e.g., a TCI field) is included in the DCI, the UE may determine the TCI state of the PDSCH based on a method other than the specified field (e.g., specified conditions or specified information).

For example, if the DCI does not include a predetermined field, the UE may determine the TCI state to be used for receiving the PDSCH based on a default TCI state or a default QCL assumption (hereinafter also referred to as the default TCI state). The default TCI state may be a TCI state corresponding to a predetermined control resource set (e.g., a predetermined control resource set in a period or slot in which the PDSCH is scheduled) (see FIG. 9). The predetermined control resource set may be the control resource set with the smallest index.

Figure 9 shows a case where PDSCH is received using a default TCI state in each beam period. The default TCI state may be a TCI state corresponding to a predetermined control resource set corresponding to each beam period.

Alternatively, the default TCI state may be a TCI state corresponding to a predetermined control resource set in the last monitored slot (e.g., the latest monitoring slot). The predetermined control resource set may be a control resource set with the smallest index. The control resource set may also be interpreted as a search space.

The default TCI state may be changed (or updated) every beam period as shown in the first aspect.

Alternatively, if the DCI does not include a specified field, the UE may control reception of the PDSCH by applying or assuming a default TCI state corresponding to a specified beam period in multiple beam periods. The specified beam period may be the beam period with the smallest index (see Figure 10). Here, a case is shown in which TCI state #1 corresponding to the beam period with the smallest index (t0) is applied or assumed in multiple beam periods (t0 to t5).

Also, if there is no control resource set (or the UE cannot detect it) in the slot where the PDSCH is scheduled, the TCI state corresponding to the control resource set last monitored by the UE may be selected as the TCI state for the PDSCH. In other words, the UE determines that the TCI state corresponding to the control resource set in the last monitoring occasion is the default TCI state (see FIG. 11A).

In Figure 11A, the UE cannot detect a control resource set (or search space) in the slot where the PDSCH is scheduled. Therefore, the TCI state corresponding to the control resource set last monitored by the UE (here, TCI state #1) is selected as the TCI state for the PDSCH (default TCI state).

Alternatively, if a control resource set does not exist (or cannot be detected by the UE) in the slot in which the PDSCH is scheduled, the TCI state corresponding to the slot (or symbol) in which the PDSCH is scheduled may be selected as the TCI state for the PDSCH (see Figure 11B).

In FIG. 11B, the UE cannot detect a control resource set (or search space) in the slot in which the PDSCH is scheduled. Therefore, the TCI state of the beam period corresponding to the slot (or symbol) in which the PDSCH is scheduled (here, TCI state #2) is selected as the TCI state for the PDSCH (default TCI state). Note that if there are multiple TCI states of the beam period corresponding to the slot (or symbol) in which the PDSCH is scheduled, a predetermined TCI state (e.g., the TCI state with the smallest index) may be selected.

Alternatively, if a control resource set does not exist (or cannot be detected by the UE) in the slot in which the PDSCH is scheduled, the TCI state corresponding to the symbol in which the PDSCH is scheduled may be selected as the TCI state for the PDSCH (see Figures 12A and B).

Figure 12A shows a case where a TCI state corresponding to at least one of the first and last symbols (here, the first symbol) for which PDSCH is scheduled is selected. Specifically, the UE may select the TCI state of the beam period corresponding to the first symbol for which PDSCH is scheduled (here, TCI state #2) as the TCI state for PDSCH (default TCI state). Note that the first symbol for which PDSCH is scheduled may be interpreted as the first symbol in which a demodulation reference signal (DMRS) for PDSCH is placed.

In FIG. 12B, the TCI state of the beam period corresponding to each symbol for which the PDSCH is scheduled (here, TCI states #2 and #3) is selected as the TCI state for the PDSCH (default TCI state). In other words, the PDSCH is received taking into account multiple TCI states in the time direction. By receiving the PDSCH taking into account multiple TCI states, the PDSCH can be received more appropriately.

The symbol to which the PDSCH is scheduled may be interpreted as a symbol to which a demodulation reference signal (DMRS) for the PDSCH is placed. In this case, when the PDSCH includes multiple DMRS, reception of the PDSCH may be controlled taking into account the TCI state corresponding to each DMRS symbol.

The second aspect may be applied to UL transmission. In this case, the default TCI state (or QCL assumption) of the PDSCH may be read as the default spatial relation of the PUCCH reference signal (e.g., PL-RS), SRS, or PUSCH.

(Third Aspect)
In the third aspect, the UE operation when the information on the beam period is not notified (for example, only the information on the transition of the TCI state is notified as the beam transition information) will be described. Note that the beam period may be read as the transition period of the TCI state, the switching period of the TCI state, or the duration of the TCI state.

If information regarding the beam period (e.g., the value of each beam period) is not notified, the UE may blindly detect at least one of each beam period and each RRH period. For example, the UE may acquire each beam period based on a predetermined signal/predetermined condition/predetermined information, and control reception of DL transmission based on the acquired beam period and the transition order of the TCI state notified by the network or defined in the specification (see Figures 13A and B).

Figure 13B shows an example of beam transition information (e.g., TCI state transition information) notified to the UE. The UE may determine the beam period or RRH period to which each TCI state corresponds based on at least one of the following options 1 to 4.

<Option 1>
The UE may determine each beam period based on a predetermined signal (or a resource for the predetermined signal). The predetermined signal may be a reference signal (DL RS). The reference signal may be at least one of a synchronization signal block, a CSI-RS, a TRS, a PT-RS, and a DMRS.

For example, the UE may determine the beam period/RRH period (hereinafter also referred to as the beam period) based on the reference signal resource (e.g., a predetermined frequency resource) or the measurement result of the reference signal transmitted using the reference signal resource. One (or a common) reference signal resource may be set for multiple beam periods (see FIG. 14). The UE may determine the reference signal resource to be set based on information on the reference signal resource configuration notified from the network.

Figure 14 shows a case where one reference signal resource (e.g., a resource to which the same frequency and periodicity is applied) is configured in multiple beam periods. The reference signal resource may be configured/triggered/activated periodically/semi-persistently/non-periodically.

The UE may measure or monitor the configured reference signal resources and determine the beam period (or the transition period of the TCI state) based on the measurement or monitoring results. For example, the UE may compare the measurement results of each reference signal resource and determine the range of each beam period based on the difference in the measurement results between different reference signal resources. The measurement or monitoring results may be at least one of the received power (RSRP), the received quality (RSRQ), and the received channel quality (SINR).

If the difference between the measurement results of different reference signal resources (e.g., adjacent reference signal resources in the time direction) is less than or equal to a predetermined value, the UE may determine that the reference signal resources belong to the same beam period (or the TCI state is not transitioned). On the other hand, if the difference between the measurement results of different reference signal resources is greater than the predetermined value, the UE may determine that each reference signal resource belongs to a different beam period (or the TCI state is transitioned). The predetermined value that serves as the criterion for judging the measurement result may be defined in the specifications or may be notified to the UE by the network.

In Figure 14, the measurement results of the reference signal resources transmitted in the beam period corresponding to TCI #0 and the measurement results of the reference signal resources transmitted in the period corresponding to TCI #1 are greater than a predetermined value, so the UE can determine the period corresponding to each TCI state based on the measurement results.

<Option 2>
In the option 1, a common reference signal resource (or a reference signal resource configuration) is set in a period (e.g., a plurality of beam periods) corresponding to a plurality of TCI states, but this is not limited to the above. A different reference signal resource (or a reference signal resource configuration) may be set or used for each period (e.g., each beam period) corresponding to each TCI state (see FIG. 15).

Figure 15 shows a case where reference signal resources (here, three different reference signal resource configurations) corresponding to the number of beam periods (here, three) are set. The different reference signal resources may be, for example, three reference signal resources having different frequency domains.

The UE may measure the RSRP/RSRQ/SINR of each reference signal resource at the configured measurement instance/time, and determine the beam period (or the transition of the TCI state) based on the resource index where the reference signal was detected/measured/received at each measurement instance. The UE may determine that the reference signal was transmitted in a reference signal resource where the measurement result is greater than a predetermined value among multiple reference signal resources.

In FIG. 15, when the UE detects a reference signal in the first reference signal resource (RS resource #1), it may determine that the beam period corresponds to TCI #0 (e.g., t0). Similarly, when the UE detects a reference signal in the second reference signal resource (RS resource #2), it may determine that the beam period corresponds to TCI #1 (e.g., t1), and when the UE detects a reference signal in the third reference signal resource (RS resource #3), it may determine that the beam period corresponds to TCI #2 (e.g., t2).

The base station may control not to transmit multiple reference signals using different reference signal resources in the same time interval (e.g., at least one of the same symbol, subslot, slot, slot, and frame). The UE may assume that multiple reference signals using different reference signal resources are not transmitted in the same time interval (e.g., at least one of the same symbol, subslot, slot, slot, and frame).

<Option 3>
In option 2, the case where reference signal resources (here, three different reference signal resource configurations) corresponding to the number of beam periods (here, three) are set is shown, but is not limited to this. The number of reference signal resources (or reference signal resource configurations) to be set may be less than the number of beam periods.

For example, two reference signal resources may be configured for multiple beam periods (or multiple transitioning TCI states). In this case, different reference signal resources may be applied (or reference signals may be placed in different reference signal resources) for adjacent beam periods (see FIG. 16).

Figure 16 shows a case in which two reference signal resources (RS resources #1 and #2) are configured in multiple beam periods (or TCI states) and different RS resources are applied in adjacent beam periods.

If the UE can detect a reference signal in the first reference signal resource (RS resource #1), it may determine that it is a beam period (e.g., t0) corresponding to TCI #0. Then, if the UE can detect a reference signal in the second reference signal resource (RS resource #2) but not in the first reference signal resource, it may determine that it has transitioned from TCI #0 (e.g., t0) to TCI #1 (e.g., t1). Then, if the UE can detect a reference signal in the first reference signal resource but not in the second reference signal resource, it may determine that it has transitioned from TCI #1 (e.g., t1) to TCI #2 (e.g., t2).

In this way, by making the number of reference signal resources smaller than the number of beam periods (or the number of TCI state transitions), it is possible to detect the beam period (or the TCI state) using fewer reference signal resources. This allows for more efficient resource usage.

<Option 4>
The switching (or change) of the beam period corresponding to each TCI state may be notified to the UE using the DCI. For example, the switching of the beam period may be notified to the UE using a new field (e.g., a duration/QCL change indicator field) included in the DCI. Alternatively, the switching of the beam period may be notified to the UE using an existing bit field (e.g., a reserved bit field) of the DCI.

Alternatively, the UE may be notified of the beam period switching based on at least one of the type of RNTI corresponding to the DCI (e.g., the RNTI used for CRC scrambling) and the DCI format.

Alternatively, the UE may determine the beam period switching based on at least one of the location and resource of the detected DCI. At least one of the location and resource of the DCI may be at least one of the CCE index, the PRB index, the resource element index, the search space index, and the CORESET ID.

<Switching timing>
When a UE switches or updates a beam period (or TCI state/QCL assumption) based on at least one of options 1 to 4, the timing/timeline of switching the beam period may be controlled based on at least one of the following timings 1 to 4 (see Figure 17).

<Timing 1>
When the UE detects a different TCI state (or a transition of the TCI state) based on the reference signal resource, the UE may switch the TCI state (or the beam period) based on the reference signal resource (or the symbol). In this case, the transition of the TCI state can be performed quickly.

<Timing 2>
When the UE detects a different TCI state (or a transition of the TCI state) based on the reference signal resource, the UE may switch the TCI state (or the beam period) based on the next reference signal resource (or symbol). In this case, the UE can secure processing time for performing the switching process.

<Timing 3>
When the UE detects a different TCI state (or a transition of the TCI state) based on the reference signal resource, the UE may switch the TCI state (or the beam period) based on at least one of the slot boundary, the subslot boundary, and the subframe boundary that includes the reference signal resource (or the symbol). In this case, the transition of the TCI state can be performed quickly.

<Timing 4>
When the UE detects a different TCI state (or a transition of the TCI state) based on the reference signal resource, the UE may switch the TCI state (or the beam period) based on at least one of the next slot boundary, subslot boundary, and subframe boundary that includes the reference signal resource (or symbol). In this case, the UE can secure processing time for performing the switching process.

(Wireless communication system)
A 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 of these.

18 is a diagram showing 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).

In addition, the wireless communication system 1 may 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.

In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (Master Node (MN)) and the NR base station (gNB) is the secondary node (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.

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

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 arranged within the macrocell C1 and form a small cell C2 that is narrower than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The arrangement and number of each cell and user terminal 20 are not limited to the aspect shown in the figure. Hereinafter, when there is no need to distinguish between base stations 11 and 12, they will be collectively referred to as base station 10.

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).

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)). Macro cell C1 may be included in FR1, and 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 correspond to a higher frequency band than FR2.

In addition, the user terminal 20 may communicate using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

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

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 at least one of, for example, an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

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

In the wireless communication system 1, a wireless access method based on Orthogonal Frequency Division Multiplexing (OFDM) may be used. For example, in at least one of the downlink (DL) and uplink (UL), 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), etc. may be used.

The radio access method may be called a waveform. In the wireless communication system 1, other radio access methods (e.g., other single-carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL radio access methods.

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.

In addition, 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.

User data, upper layer control information, System Information Block (SIB), etc. are transmitted by the PDSCH. User data, upper layer control information, etc. may be transmitted by the PUSCH. In addition, Master Information Block (MIB) may be transmitted by the PBCH.

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

In addition, the DCI for scheduling the PDSCH may be called a DL assignment, DL DCI, etc., and the DCI for scheduling the PUSCH may be called a UL grant, UL DCI, etc. In addition, the PDSCH may be replaced with DL data, and the PUSCH may be replaced with UL data.

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

One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as 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 as interchangeable.

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

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

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, as the DL-RS, 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.

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 an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS/PBCH block, an SS Block (SSB), etc. In addition, the SS, SSB, etc. may also be referred to as a reference signal.

In addition, 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 be called a user equipment specific reference signal (UE-specific Reference Signal).

(base station)
19 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 one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140 may be provided.

In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and the base station 10 may be assumed to have other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, a control circuit, etc., which are described based on a common understanding in the technical field to which the present disclosure relates.

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 transmission and reception unit 120, the transmission and reception antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transmission and reception unit 120. The control unit 110 may perform call processing of communication channels (setting, release, etc.), status management of the base station 10, management of radio resources, etc.

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 composed of 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 a common understanding in the technical field related to the present disclosure.

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.

The transmitting/receiving antenna 130 may be constructed from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

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.

The transceiver unit 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver unit 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.

The transceiver unit 120 (transmission processing unit 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 sequence to be transmitted, and output a baseband signal.

The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

The transceiver unit 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, and acquire user data, etc.

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.

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.

In addition, the transmitting unit and receiving unit of the base station 10 in the present disclosure may be constituted by at least one of the transmitting/receiving unit 120, the transmitting/receiving antenna 130, and the transmission path interface 140.

The transceiver unit 120 may transmit at least one of information regarding transitions of states of multiple transmission configuration indicators (TCIs) that can be used for DL transmission transmitted from one or more transmission points located on the movement path, information regarding periods corresponding to each of the multiple TCIs, and information regarding periods corresponding to the transmission points.

The transceiver unit 120 may transmit information regarding transitions of multiple transmission configuration indicator (TCI) states that may be utilized for DL transmissions transmitted from one or more transmission points located along the movement path.

The control unit 110 may control the TCI state to be used for DL transmission based on the transition of the TCI state.

The control unit 110 may control the transmission of at least one of a plurality of DL reference signals and downlink control information used to identify periods corresponding to a plurality of TCI states.

(User terminal)
20 is a diagram showing an example of the configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transmitting/receiving unit 220, and a transmitting/receiving antenna 230. Note that the control unit 210, the transmitting/receiving unit 220, and the transmitting/receiving antenna 230 may each be provided in one or more units.

In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and the user terminal 20 may be assumed to have other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, a control circuit, etc., which are described based on a common understanding in the technical field to which the present disclosure relates.

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

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 a common understanding in the technical field related to the present disclosure.

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

The transmit/receive antenna 230 may be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

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.

The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver unit 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.

The transceiver unit 220 (transmission processing unit 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 sequence to be transmitted, and output a baseband signal.

In addition, 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 above-mentioned transmission processing to transmit the channel using a DFT-s-OFDM waveform, and if not, it is not necessary to perform DFT processing as the above-mentioned transmission processing.

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

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

The transceiver unit 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, and acquire user data, etc.

The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, 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.

In addition, the transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be constituted by at least one of the transmitting/receiving unit 220 and the transmitting/receiving antenna 230.

The transceiver unit 220 may receive at least one of information regarding transitions of states of multiple transmission configuration indicators (TCIs) that may be used for DL transmission transmitted from one or more transmission points located on the movement path, information regarding periods corresponding to each of the multiple TCIs, and information regarding periods corresponding to the transmission points.

The transceiver 220 may receive information regarding transitions of multiple transmission configuration indicator (TCI) states that may be utilized for DL transmissions transmitted from one or more transmission points located along the movement path.

The control unit 210 may control reception of DL transmissions transmitted from the transmission point based on the received information. For example, the control unit 210 may control to change the assumed TCI state for DL transmissions when at least one of the periods corresponding to the multiple TCIs and the periods corresponding to the transmission point expires. The control unit 210 may also control reception for some of the DL transmissions based on the received information, and control reception for other DL transmissions based on the TCI state notified in the downlink control information or the default TCI state. A separate list of TCI states may be set for each period corresponding to each of the multiple TCIs.

The control unit 210 may determine the periods corresponding to the multiple TCI states based on at least one of the multiple DL reference signals and the downlink control information. The multiple DL reference signals may be transmitted using a common resource. The multiple DL reference signals may be transmitted using different resources for each period corresponding to the multiple TCI states. The control unit 210 may determine the periods corresponding to the multiple TCI states based on the difference between the measurement results of the multiple reference signals and at least one of the resources used for the multiple reference signals.

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

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 the transmission function may be called a transmitting unit, transmitter, etc. In either case, as described above, there is no particular limitation on the method of realization.

For example, a base station, a user terminal, etc. in one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 21 is a diagram showing an example of the hardware configuration of a base station and a user terminal according to one embodiment. The above-mentioned 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.

In this disclosure, the terms apparatus, circuit, device, section, unit, etc. may be interpreted 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 figures, or may be configured to exclude some of the devices.

For example, although only one processor 1001 is shown, there may be multiple processors. Also, the processing may be performed by one processor, or the processing may be performed by two or more processors simultaneously, sequentially, or using other techniques. The processor 1001 may be implemented by one or more chips.

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

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

In addition, the processor 1001 reads out 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 according to these. The programs used are those that cause a computer to execute at least some of the operations described in the above-mentioned 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 similar implementations may be made for other functional blocks.

The memory 1002 is a computer-readable recording medium and may be composed of at least one of, for example, a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically EPROM (EEPROM), a Random Access Memory (RAM), or other suitable storage media. The memory 1002 may be called 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 one embodiment of the present disclosure.

Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (e.g., a compact disk (Compact Disc ROM (CD-ROM)), a digital versatile disk, a Blu-ray (registered trademark) disk), 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 an auxiliary storage device.

The communication device 1004 is hardware (transmission and reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, a communication module, etc. 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 and reception unit 120 (220), transmission and reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission and 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.

The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a Light Emitting Diode (LED) lamp, etc.) that performs output to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one configuration (e.g., a touch panel).

In addition, 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.

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 the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

(Modification)
In addition, the terms described in this disclosure and the terms necessary for understanding this 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 read as mutually interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may be called a pilot, a pilot signal, or the like depending on the applied standard. A component carrier (CC) may also be called a cell, a frequency carrier, a carrier frequency, or the like.

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.

Here, the numerology may be a communication parameter applied to at least one of the transmission and reception of a signal or channel. The numerology may indicate at least one of, for example, SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame configuration, a specific filtering process performed by the transceiver in the frequency domain, and a specific windowing process performed by the transceiver in the time domain.

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

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.

A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting a signal. A different name may be used for 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 this disclosure may be read as interchangeable with each other.

For example, one subframe may be called a TTI, multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. In other words, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

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

A TTI may be a transmission time unit for a channel-coded 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) in which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

In addition, 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 of scheduling. In addition, the number of slots (minislots) constituting the minimum time unit of scheduling may be controlled.

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

Note that a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length less than the TTI length of a long TTI and equal to or greater than 1 ms.

A resource block (RB) is a resource allocation unit in the time domain and 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, and may be, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

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

In addition, one or more RBs may be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

A resource block may also 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.

A Bandwidth Part (BWP), which may also be referred to as partial 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 an index of the RB relative to a common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

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

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".

The above-mentioned structures of radio frames, subframes, slots, minislots, and symbols 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, as well as the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length can be changed in various ways.

In addition, the information, parameters, etc. described in the present disclosure may be represented using absolute values, may be represented using relative values from a predetermined value, or may be represented using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

The names used for parameters, etc. in this disclosure are not limiting in any respect. Furthermore, the formulas, etc. 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 the various names assigned to these various channels and information elements are not limiting in any respect.

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

In addition, 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.

Input/output information, signals, etc. may be stored in a specific location (e.g., memory) or may be managed using a management table. Input/output information, signals, etc. may be overwritten, updated, or appended. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

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), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB), etc.), Medium Access Control (MAC) signaling), other signals, or combinations thereof.

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. The RRC signaling may be called an RRC message, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc. The MAC signaling may be notified, for example, using a MAC Control Element (CE).

In addition, 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).

The determination may be based on a value represented by a single bit (0 or 1), a Boolean value represented as true or false, or a numerical comparison (e.g., with a predetermined value).

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.

Additionally, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, if the 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, etc.), then these wired and/or wireless technologies are included within the definition of a transmission medium.

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., a base station).

In this 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," and "panel" may be used interchangeably.

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.

A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small base station for indoor use (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of at least one of the base station and base station subsystems that provide communication services in this coverage.

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

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.

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 moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may include a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

In addition, the base station in the present disclosure may be read as a user terminal. For example, each aspect/embodiment 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), Vehicle-to-Everything (V2X), etc.). In this case, the user terminal 20 may be configured to have the functions possessed by the above-mentioned base station 10. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, the uplink channel, the downlink channel, etc. may be read as a side channel.

Similarly, the user terminal in the present disclosure may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the user terminal 20 described above.

In the present disclosure, operations that are described as being performed by a base station may in some cases be performed by its upper node. In a network including one or more network nodes having base stations, it is clear that various operations performed for communication with terminals 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), a Serving-Gateway (S-GW), etc.), or a combination thereof.

Each aspect/embodiment described in this disclosure may be used alone, in combination, or switched between depending on the implementation. In addition, the processing procedures, sequences, flow charts, etc. of each aspect/embodiment described in this disclosure may be reordered as long as there is no inconsistency. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

Each aspect/embodiment described in this disclosure is a part of 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), 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 using 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), other appropriate wireless communication methods, next-generation systems that are based on these, etc. Also, a combination of multiple systems (for example, a combination of LTE or LTE-A and 5G) may be applied.

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."

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

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, and the like.

"Determining" may also be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in a memory), etc.

In addition, "judgment" may be considered to be "judging" resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" may be considered to be "judging" some action.

In addition, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," etc.

As used in this disclosure, the terms "connected" and "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 the elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

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, and the like, as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, and the like, as some non-limiting and non-exhaustive examples.

In this disclosure, the term "A and B are different" may mean "A and B are different from each other." In addition, the term may mean "A and B are each different from C." Terms such as "separate" and "combined" may also be interpreted in the same way as "different."

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

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

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

Claims (4)

A receiving unit that receives information on a transition order of a plurality of transmission configuration indicators (TCIs) that can be used for DL transmission transmitted from one or more transmission points arranged on a moving path, information on a period corresponding to each of the plurality of TCIs, and information on a period corresponding to the transmission point;
A control unit that controls reception of DL transmission transmitted from the transmission point based on the received information ,
The control unit changes the assumption of the TCI state for the DL transmission in accordance with information on the order of transition of the TCI state contained in the information when at least one of the periods corresponding to the multiple TCIs and the period corresponding to the transmission point expires . a separate list of TCI states is set for each period corresponding to each of the plurality of TCIs ;
The terminal according to claim 1, characterized in that the control unit selects one list from the list of separate TCI states based on downlink control information, and controls reception based on the TCI state of a corresponding period among the TCI states included in the selected list . receiving information on a sequence of transitions of a plurality of transmission configuration indicators (TCIs) states that may be utilized for DL transmissions transmitted from one or more transmission points disposed on a moving path, information on time periods corresponding to the plurality of TCIs, and information on time periods corresponding to the transmission points;
and controlling reception of DL transmissions transmitted from the transmission point based on the received information ;
A wireless communication method characterized in that, when at least one of the periods corresponding to the multiple TCIs and the period corresponding to the transmission point expires, the assumed TCI state for the DL transmission is changed in accordance with information on the order of TCI state transitions contained in the information . A transmitter that transmits information on a transition order of a plurality of transmission configuration indicators (TCIs) that can be used for DL transmission transmitted from one or more transmission points arranged on a moving path, information on a period corresponding to each of the plurality of TCIs, and information on a period corresponding to the transmission point;
A control unit that controls a TCI state to be used for the DL transmission based on a transition order of the TCI state ,
A base station characterized in that, when at least one of the periods corresponding to the multiple TCIs and the periods corresponding to the transmission points expires, a TCI state for the DL transmission is changed in accordance with information on a transition order of the TCI state included in the information .

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