WO2024082622A1

WO2024082622A1 - Early beam activation and beam indication for ltm

Info

Publication number: WO2024082622A1
Application number: PCT/CN2023/094241
Authority: WO
Inventors: Bingchao LIU; Chenxi Zhu; Lianhai WU; Shuigen Yang
Original assignee: Lenovo (Beijing) Ltd.
Priority date: 2023-05-15
Filing date: 2023-05-15
Publication date: 2024-04-25

Abstract

Methods and apparatuses for early beam activation for LTM are disclosed. In one embodiment, a UE comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to receive, via the transceiver, a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

Description

EARLY BEAM ACTIVATION AND BEAM INDICATION FOR LTM

FIELD

The subject matter disclosed herein generally relates to wireless communications, and more particularly relates to methods and apparatuses for layer 1 (L1) measurement and beam indication for L1/layer 2 (L2) triggered mobility (LTM) .

BACKGROUND

Different from layer 3 (L3) based mobility, L1 measurements based on Channel State Information (CSI) reporting framework are used for L1/L2 triggered mobility (LTM) . It means that the User Equipment (UE) can be configured to measure the qualities of different candidate cells in layer 1 and report the measurement results of the candidate cells to the serving cell in one or more CSI (Channel State Information) reports. If the UE reports that one of the candidate cells is better than the current serving cell, the gNB may indicate a cell switch command by a MAC CE to the UE to indicate the UE to switch to the candidate cell.

Dedicated Radio Resource Control (RRC) signaling other than CSI report configuration (e.g., CSI-ReportConfig IE (information element) that is specified in NR Release 17 for CSI report configuration) may be used for LTM report configuration. In other words, separate configuration other than CSI report configuration may be configured for L1 measurement and report for LTM.

This invention targets early beam activation and/or indication for LTM and L1 measurement for LTM.

BRIEF SUMMARY

Methods and apparatuses for early beam activation for LTM are disclosed.

In one embodiment, a UE comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to receive, via the transceiver, a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In some embodiment, the processor is further configured to receive, via the transceiver, a cell switch command or a DCI that indicates a TCI state, wherein, the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell. In some embodiment, the processor is further configured to receive, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied. In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is received before receiving the cell switch command. Alternatively, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.

In some embodiment, the MAC CE includes a BWP ID field to indicate the initial BWP when the candidate cell is indicated as a target cell.

In some embodiment, the processor is further configured to transmit, via the transceiver, UE capabilities including: the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.

In another embodiment, a method performed at a UE comprises receiving a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In still another embodiment, a base unit comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to transmit, via the transceiver, a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In yet another embodiment, a method performed at a base unit comprises transmitting a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only some embodiments, and are not therefore to be considered to be limiting of scope, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:

Figure 1 illustrates an example of the format of the enhanced unified TCI state activation/deactivation MAC CE;

Figure 2 illustrates an exemplary LTM report configuration;

Figure 3 is a schematic flow chart diagram illustrating an embodiment of a first method;

Figure 4 is a schematic flow chart diagram illustrating another embodiment of the first method;

Figure 5 is a schematic flow chart diagram illustrating an embodiment of a second method;

Figure 6 is a schematic flow chart diagram illustrating another embodiment of the second method;

Figure 7 is a schematic flow chart diagram illustrating an embodiment of a third method;

Figure 8 is a schematic flow chart diagram illustrating another embodiment of the third method;

Figure 9 is a schematic flow chart diagram illustrating an embodiment of a fourth method;

Figure 10 is a schematic flow chart diagram illustrating another embodiment of the fourth method;

Figure 11 is a schematic block diagram illustrating apparatuses according to one embodiment; and

Figure 12 is a schematic block diagram illustrating apparatuses according to another embodiment.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art that certain aspects of the embodiments may be embodied as a system, apparatus, method, or program product. Accordingly, embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc. ) or an embodiment combining software and hardware aspects that may generally all be referred to herein as a “circuit” , “module” or “system” . Furthermore, embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer readable code, and/or program code, referred to hereafter as “code” . The storage devices may be tangible, non-transitory, and/or non-transmission. The storage devices may not embody signals. In a certain embodiment, the storage devices only employ signals for accessing code.

Certain functional units described in this specification may be labeled as “modules” , in order to more particularly emphasize their independent implementation. For example, a module may be implemented as a hardware circuit comprising custom very-large-scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

Modules may also be implemented in code and/or software for execution by various types of processors. An identified module of code may, for instance, include one or more physical or logical blocks of executable code which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but, may include disparate instructions stored in different locations which, when joined logically together, include the module and achieve the stated purpose for the module.

Indeed, a module of code may contain a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules and may be embodied in any suitable form and organized within any suitable type of data structure. This operational data may be collected as a single data set, or may be distributed over different locations including over different computer readable storage devices. Where a module or portions of a module are implemented in software, the software portions are stored on one or more computer readable storage devices.

Any combination of one or more computer readable medium may be utilized. The computer readable medium may be a computer readable storage medium. The computer readable storage medium may be a storage device storing code. The storage device may be, for example, but need not necessarily be, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

A non-exhaustive list of more specific examples of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, random access memory (RAM) , read-only memory (ROM) , erasable programmable read-only memory (EPROM or Flash Memory) , portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may include any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages. The code may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the very last scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN) , or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider) .

Reference throughout this specification to “one embodiment” , “an embodiment” , or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment” , “in an embodiment” , and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including” , “comprising” , “having” , and variations thereof mean “including but are not limited to” , unless otherwise expressly specified. An enumerated listing of items does not imply that any or all of the items are mutually exclusive, otherwise unless expressly specified. The terms “a” , “an” , and “the” also refer to “one or more” unless otherwise expressly specified.

Furthermore, described features, structures, or characteristics of various embodiments may be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments. One skilled in the relevant art will recognize, however, that embodiments may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid any obscuring of aspects of an embodiment.

Aspects of different embodiments are described below with reference to schematic flowchart diagrams and/or schematic block diagrams of methods, apparatuses, systems, and program products according to embodiments. It will be understood that each block of the schematic flowchart diagrams and/or schematic block diagrams, and combinations of blocks in the schematic flowchart diagrams and/or schematic block diagrams, can be implemented by code. This code may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the schematic flowchart diagrams and/or schematic block diagrams for the block or blocks.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices, to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code executed on the computer or other programmable apparatus provides processes for implementing the functions specified in the flowchart and/or block diagram block or blocks.

The schematic flowchart diagrams and/or schematic block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of apparatuses, systems, methods and program products according to various embodiments. In this regard, each block in the schematic flowchart diagrams and/or schematic block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions of the code for implementing the specified logical function (s) .

It should also be noted that in some alternative implementations, the functions noted in the block may occur out of the order noted in the Figures. For example, two blocks shown in succession may substantially be executed concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more blocks, or portions thereof, to the illustrated Figures.

Although various arrow types and line types may be employed in the flowchart and/or block diagrams, they are understood not to limit the scope of the corresponding embodiments. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the depicted embodiment. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted embodiment. It will also be noted that each block of the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and code.

The description of elements in each Figure may refer to elements of proceeding figures. Like numbers refer to like elements in all figures, including alternate embodiments of like elements.

A first embodiment relates to early beam activation and indication for LTM.

The motivation of LTM is to reduce the handover latency compared with L3 triggered mobility. To further reduce the handover latency, beam indication (i.e., Transmission Configuration Indicator (TCI) state indication where each TCI state corresponds to a beam) can be contained in the cell switching command (CSC) or be indicated before the UE receives the CSC. Before the base unit (e.g., Next Generation Node B (gNB) ) sends the beam indication message, TCI state (s) activation for a potential target cell (i.e., a candidate cell) may be expected by the UE. In other words, the candidate cell TCI state activation command is expected to be received before the UE receives the CSC.

A first sub-embodiment of the first embodiment relates to TCI state and TRS preparation for inter-DU (Distributed Unit) scenario.

Before the UE receives the candidate cell TCI state activation command, the UE expects to receive the TCI states configuration of the candidate cell.

The CSC indicates the UE to handover from a source cell (i.e., the current serving cell) to a target cell (e.g., one of the candidate cells) . It is assumed that both the source cell and the target cell belong to a same base unit (e.g., gNB) . Considering the CU (Centralized Unit) - DU(Distributed Unit) split, the source cell and the target cell may belong to the same DU or different DUs.

A brief introduction of CU-DU split is provided. In a scenario of single gNB with CU-DU split architecture, one gNB can be composed of one gNB-CU (referred to as CU) and at least one gNB-DU (e.g., two or more gNB-DUs, each of which is referred to as a DU) . There is F1 interface between CU and each DU. F1 interface is composed of F1-C (i.e., for control plane) and F1-U (i.e., for user plane) . CU is responsible for Service Data Adaptation Protocol (SDAP) layer and Packet Data Convergence Protocol (PDCP) layer of the radio interface. DU is responsible for Radio Link Control (RLC) layer, Media Access Control (MAC) layer and physical (PHY) layer of the radio interface.

An intra-DU scenario refers to a scenario in which both the source cell and the target cell belong to the same DU. In this condition, the TCI states configuration of the target cell (i.e., one of candidate cells) is known by the DU to which the source cell belong.

An inter-DU scenario refers to a scenario in which the source cell belongs to a source DU and the target cell belongs to a target DU, where the source DU and the target DU belong to the same CU. In this condition, the source DU needs to know the TCI states configuration of the target cell that belongs to the target DU.

There can be one or more candidate cells, each of which can be chosen (or indicated) as a target cell to which the UE handovers.

In one solution, the target DU can directly send the TCI states configuration of each candidate cell that belongs to the target DU to the source DU via the CU, where the serving cell of the UE belongs to the source DU.

Alternatively, the source DU can send a request to the target DU via the CU to send the TCI states configuration of one or more candidate cells belonging to the target DU. Upon receiving the request from the source DU, the target DU sends the TCI states configuration of each requested candidate cell to the source DU via the CU.

After receiving the TCI states configurations of candidate cells (or the TCI states configurations of candidate cells being known) , the source DU may send TCI states configurations to the UE.

Since the UE may be required to track the Tracking Reference Signal (TRS) configured in the activated or indicated TCI state for a candidate cell, it is preferable that the TRS configuration of TRS configured in each TCI state (referred to as TRS configuration for each TCI state hereinafter) for a candidate cell should be provided along with the TCI states configuration of the candidate cell, where each TCI state refers to each of the TCI states included in the TCI states configuration for a candidate cell. Each TCI state is used to indicate one or two DL RSs for the UE to obtain the DL channel characteristics for a certain DL reception, where the first DL RS can be used to obtain the Doppler shift, Doppler spread, average delay and delay spread of the DL channel, and the second DL RS can be used to determine the spatial RX filter parameter for the DL reception, i.e., to determine the beam for the DL reception. The first RS and the second RS contained in the TCI state may be a same TRS. TRS is a type of channel state information reference signal (CSI-RS) with single port and is configured by a dedicated RRC parameter, e.g., trs-info is configured for a CSI-RS resource to identify a TRP.

So, when the target DU sends the TCI states configuration to the source DU via the CU, the TRS configuration for each TCI state included in the TCI states configuration for a candidate cell shall be sent along with the TCI states configuration for the candidate cell. Similarly, when the source DU sends the TCI states configuration to the UE, the TRS configuration for each TCI state included in the TCI states configuration for a candidate cell can be sent along with the TCI states configuration for the candidate cell.

A second sub-embodiment of the first embodiment relates to early TCI state activation.

TCI state activation for a candidate cell can be achieved by an enhanced unified TCI state activation/deactivation Media Access Control (MAC) control element (CE) . In other words, traditional unified TCI state activation/deactivation MAC CE, that is used to activate TCI states for the serving cell, can be enhanced for TCI state activation for a candidate cell

An example of the format of the enhanced unified TCI state activation/deactivation MAC CE is shown in Figure 1. The enhanced unified TCI state activation/deactivation MAC CE includes the following fields: “S/C” field, “Serving cell ID or candidate cell index” field, “BWP ID” field (i.e., “DL BWP ID” field and “UL BWP ID” field) , “Pi” field (where i is from 1 to 8) , “D/U” fields, and “TCI state ID n” field (where n is from 1 to N) .

“S/C” field indicates the MAC CE is used for serving cell TCI state activation or candidate cell TCI state activation.

When the “S/C” field indicates that the MAC CE is used for serving cell TCI state activation, the “Serving cell ID or candidate cell index” field indicates the serving cell for which the MAC CE applies.

When the “S/C” field indicates that the MAC CE is used for candidate cell TCI state activation, the “Serving cell ID or candidate cell index” field indicates a candidate cell for which the MAC CE applies.

When the “S/C” field indicates that the MAC CE is used for candidate cell TCI state activation, the “BWP ID” field indicates the initial bandwidth part (BWP) when the candidate cell is indicated as the target cell (i.e., when the UE is indicated to switch to target cell that is the candidate cell indicated by the “Serving cell ID or candidate cell index” field of the MAC CE) . In particular, “DL BWP ID” field and “UL BWP ID” field indicate the initial downlink (DL) BWP and initial uplink (UL) BWP, respectively.

Each “Pi” field indicates the TCI codepoint i is mapped with one or two TCI states. If TCI codepoint i is mapped with one TCI state, one “TCI state ID n” field indicates the one TCI state; and if TCI codepoint i is mapped with two TCI states, each of two “TCI state ID n” fields indicates one of the two TCI states. It implies that N ranges from 8 to 16, depending on how many “Pi” fields indicates the TCI codepoint i being mapped with one TCI state (or how many “Pi” fields indicates the TCI codepoint i being mapped with two TCI states) .

Each of the “TCI state ID n” fields indicates the TCI state for TCI codepoint i in a sequential manner. For example, if “P1” field indicates the TCI codepoint 1 being mapped with two TCI states, “TCI state ID 1” and “TCI state ID 2” fields indicate the two TCI states; and if “P2” field indicates the TCI codepoint 2 being mapped with one TCI state, “TCI state ID 3” fields indicate the one TCI state, …and so on.

Each “D/U” field indicates the following TCI state is a DL TCI state or a UL TCI state. A DL TCI state can also be a joint TCI state (i.e., be used as both a DL TCI state and a UL TCI state) .

As a whole, the enhanced unified TCI state activation/deactivation MAC CE can activate the TCI states for the serving cell, or activate the TCI states for a candidate cell before the UE receives the CSC.

A third sub-embodiment of the first embodiment relates to early beam indication.

As mentioned earlier, the beam indication (i.e., TCI state indication) can be contained in the CSC.

If the CSC contains the TCI state indication field that indicates the TCI state of the target cell, the indicated TCI state should be one or two of the activated TCI states (e.g., activated by the enhanced unified TCI state activation/deactivation MAC CE) for the target cell. Incidentally, the indicated TCI state of the target cell can be one TCI state (i.e., a joint TCI state) or a pair of DL TCI state and UL TCI state.

On the other hand, if the CSC does not contain the TCI state indication (i.e., the TCI state for the target cell is not indicated in the CSC) , four options are proposed to indicate the TCI state for the target cell.

Option 1: The TCI state for the candidate cell (i.e., a joint TCI state or a pair of UL TCI state and DL TCI state) can be indicated by the DCI (Downlink Control Information) format 1_1 or 1_2 with CRC (Cyclic Redundancy Check) scrambled by a dedicated configured RNTI (Radio Network Temporary Identity) (i.e., a RNTI associated with the candidate cell) before the UE receives the CSC.

Option 2: The TCI state for the candidate cell (i.e., a joint TCI state or a pair of UL TCI state and DL TCI state) can be indicated by the DCI format 1_1 or 1_2 with CRC scrambled by C-RNTI (Cell Radio Network Temporary Identity) of the serving cell before the UE receives the CSC. In order to differentiate whether the indicated TCI state is applied for the serving cell or a candidate cell, a new DCI field can be configured in the DCI format 1_1 or 1_2 to indicate whether the indicated TCI state is applied for the serving cell or the candidate cell (or which one of the candidate cells if there are multiple candidate cells) .

Option 3: When TCI states for multiple candidate cells are activated, the TCI state for the candidate cell (i.e., a joint TCI state or a pair of UL TCI state and DL TCI state) can be indicated by the DCI format 1_1 or 1_2 with CRC scrambled by C-RNTI of the serving cell) . A candidate cell index field can be configured in the DCI format 1_1 or 1_2 to indicate the indicated TCI state is applied to which one of the multiple candidate cells.

Option 4: The TCI state for the candidate cell (i.e., a joint TCI state or a pair of UL TCI state and DL TCI state) can be indicated by the DCI format 1_1 or 1_2 with CRC scrambled by C-RNTI associated with the target cell after the UE receives the CSC.

If the BWP ID (e.g., UL BWP ID and/or DL BWP ID) for the target cell are not provided in the CSC, the UE shall assume the initial BWP indicated by the BWP ID field in the enhanced unified TCI state activation/deactivation MAC CE for the target cell. In particular, the UL BWP ID indicated by the “UL BWP ID” field and/or the DL BWP ID indicated by the “DL BWP ID” field are assumed to be the initial UL BWP and/or the initial DL BWP for the target cell.

A fourth sub-embodiment of the first embodiment relates to early TRS tracking.

To support early data transmission in the target cell with the indicated TCI state, early TRS tracking should be supported by the UE to obtain the basic channel priority for channel estimation. To simplify the UE behavior, it is proposed that the UE only needs to track the TRS configured in the indicated TCI state of the target cell. In other words, when the indicated TCI state is applied in the target cell, the UE expects to receive the TRS configured in the indicated TCI state of the target cell for QCL (Quasi-CoLocation) tracking.

A fifth sub-embodiment of the first embodiment relates to UE capabilities related to early beam activation and indication for LTM.

Considering different UE capabilities, the UE shall report the following capabilities for early TCI state activation and indication to the network (e.g., to gNB) :

the maximum number of activated TCI states and maximum number of indicated TCI states for all the candidate cells configured in the serving cell; and

the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.

The value of 1 should at least be included for “the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell” if the UE supports early beam indication for LTM.

A second embodiment relates to resource configuration and report configuration for LTM.

It was agreed that a dedicated RRC signaling is used to configure the RS related parameters for L1 measurement, e.g., PCI (Physical Cell ID) or logical ID, SMTC location (where SMTC stands for SSB-MTC, i.e., SSB (synchronization signal /Physical Broadcast Channel block) measurement timing configuration) , frequency location and SCS (subcarrier spacing) . In addition, the reporting configuration for LTM is provided inside the serving cell configuration (e.g., ServingCellConfig IE) of current serving cell. Note that the ServingCellConfig IE is used to configure (e.g., add or modify) the UE with a serving cell.

A first sub-embodiment of the second embodiment relates to resource set configuration.

To support LTM, multiple candidate cells can be configured for the UE for L1 measurement. For each candidate cell, SSB-MTC will be provided to indicate the SSB positions and SSB periodicity for SSB reception.

One or more resource settings can be configured for the UE, where each resource setting contains a list of resource sets for LTM measurement. Each resource set contains the SSB resources from one or more candidate cells.

Preferably, a measurement gap can be configured for the UE to periodically receive the SSB from candidate cells. The measurement gap has a configuration duration, periodicity and offset. SSBs are to be received in the measurement gap. The SSB resources contained in a same resource set are expected to be located in a same measurement gap.

The measurement gap can be optionally configured for intra-frequency LTM (which means that the source cell (i.e., serving cell) and the target cell are in the same frequency) , and be preferably configured for inter-frequency LTM (which means that the source cell (i.e., serving cell) and the target cell are in different frequencies) . For inter-frequency LTM, the UE needs to switch to the frequency of the target cell to measure the SSBs for the target cell.

A second sub-embodiment of the second embodiment relates to reporting configuration for LTM:

A UE that supports LTM can be configured with multiple LTM report configurations, where each LTM report configuration can be referred to as LTM-ReportConfig IE. Each LTM report configuration is associated with one or more resource sets for channel measurement.

An exemplary LTM report configuration is shown in Figure 2.

It can be seen that an LTM report can be periodic, semi-persistent on PUCCH (Physical Uplink Control Channel) , semi-persistent on PUSCH (Physical Uplink Shared Channel) , or aperiodic.

Periodic LTM report is carried by PUCCH resource and triggered by RRC signaling.

Semi-persistent LTM report on PUCCH is activated by MAC CE.

Semi-persistent LTM report on PUSCH is activated by DCI.

Aperiodic LTM report is triggered by DCI and carried by PUSCH.

Alternative to a separate LTM report configuration, the reporting configuration for LTM can be configured by CSI report configuration (e.g., CSI-ReportConfig IE) contained in the serving cell configuration (e.g., ServingCellConfig IE) of current serving cell (s) , and be referred to as CSI report configuration for LTM.

Each resource (e.g., SSB resource) in a resource set associated with a CSI report configuration for LTM or a LTM report configuration (e.g., LTM-ReportConfig IE) is associated with a candidate cell configuration index, or a PCI or a logical ID. Preferably, all the resources (e.g., SSB resources) associated with a same CSI report configuration for LTM are covered by a same measurement gap to reduce the measurement overhead.

If the LTM report is separately configured by the LTM report configuration, a triggering signaling is required for triggering the LTM report.

Aperiodic LTM report can be triggered by DCI format 0_1 or DCI format 0_2 with CRC scrambled by C-RNTI.

Semi-persistent LTM report can be activated by DCI format 0_1 or DCI format 0_2 with CRC scrambled by CS-RNTI (Configured Scheduling RNTI) .

The triggering DCI or activating DCI also indicates the UL resources, i.e., time and frequency resources for PUSCH transmission, for the LTM report.

Two methods are proposed on how the LTM report is triggered or activated by DCI (e.g., DCI format 0_1 or DCI format 0_2) .

Method 1-1: a dedicated DCI field, e.g., LTM request field, can be configured in the triggering DCI or activating DCI for triggering or activating the LTM report.

Method 1-2: the CSI request field, which has been included in the triggering DCI or activating DCI, can be reused for triggering or activating the LTM report. In addition, a new indication field is added to the triggering DCI or activating DCI to indicate the CSI request field is used for triggering or activating CSI report or for triggering or activating LTM report. For example, the new indication field may include 2 bits. In particular, value ‘00’ indicates that the CSI request field is used for triggering aperiodic CSI report or activating semi-persistent CSI report; value ‘01’ indicates that the CSI request field is used for triggering aperiodic LTM report or activating semi-persistent LTM report; value ‘10’ indicates that the CSI request field is used for triggering or activating both CSI report and LTM report; and value ‘11’ may be reserved.

The value of the LTM request field in Method 1-1 or the value of the CSI request field (if it is used for triggering or activating LTM report) in Method 1-2 is referred to as a codepoint.

Two methods are proposed for the association between the codepoint and the triggered LTM report as follows:

Method 2-1: each codepoint is associated with an aperiodic LTM report configuration, for example, by referring to an association table. An example of the association table is shown in Table 1.

Table 1

According to method 2-1, the number of aperiodic LTM report configurations shall be smaller than or equal to the number of non-zero codepoints.

Method 2-2: A list of aperiodic LTM trigger states are configured by an RRC signaling, where each LTM trigger state is associated with one or more LTM report configurations. When the number of configured aperiodic LTM trigger states is larger than the number of non-zero codepoints, MAC CE based aperiodic LTM trigger state activation can used to map each codepoint to one of the aperiodic LTM trigger states. When the number of configured aperiodic LTM trigger states is equal to or less than the number of non-zero codepoints, each LTM request field codepoint is mapped to one aperiodic LTM trigger state.

Since an aperiodic LTM trigger state can be associated with one or more LTM report configurations and each codepoint can be dynamically mapped to one of the aperiodic LTM trigger states, Method 2-2 applies especially to the situation that the number of aperiodic LTM report configurations are larger than the number of non-zero codepoints.

A third sub-embodiment of the second embodiment relates to LTM report priority:

The measurement results corresponding to a LTM report shall be reported as a type of UCI and may be multiplexed with the traditional UCIs, e.g., CSI corresponding to CSI report, HARQ (Hybrid Automatic Repeat reQuest) and SR (Scheduling Request) in a same UL resource. Since the LTM report is configured different from the CSI report, a new priority level is required for UCI multiplexing with LTM report.

This disclosure proposes that the priority of LTM report is lower than HARQ and SR but higher than CSI report when performing UCI multiplexing. In other words, the priorities of different UCI types are ordered as SR > HARQ > LTM report > CSI report. For example, when two CSI reports, one for legacy (i.e., for CSI) and the other for LTM (i.e., being a LTM report) , are triggered to be reported in two overlapped PUSCHs (which means that only one of them can be reported) , the UE shall only report the LTM report and drop the CSI report for legacy CSI.

In addition, when LTM report is configured with LTM report configuration, when LTM reports corresponding to different LTM report configurations are overlapped (e.g., in a same slot to report) , a priority rule is required for different types of LTM reports.

Each LTM report can be associated with a priority value Pri_iLTM (y, c, s) =2·N_cells·M_LTM·y+M_LTM·c+S, where

y = 0 for aperiodic LTM reports to be carried on PUSCH, y = 1 for semi-persistent LTM reports to be carried on PUSCH, y = 2 for semi-persistent LTM reports to be carried on PUCCH and y = 4 for periodic LTM reports to be carried on PUCCH;

c is the serving cell index;

s is the LTM report configuration index (e.g., LTM-reportConfigID) ;

N_cells is the number of serving cells configured for the UE;

M_LTM is the maximum number of configured LTM report configurations.

A first LTM report is said to have higher priority than a second LTM report if the Pri_iLTM (y, c, s) value associated with the first LTM report is lower that the Pri_iLTM (y, c, s) value associated with than the second LTM report.

If two LTM reports are collided, the LTM report with lower priority may be dropped.

A fourth sub-embodiment of the second embodiment relates to reference resource for a LTM report.

As described in above 1) , measurement gap may be introduced for L1 measurement for LTM. Each measurement gap is consisted of one or more continuous slots used for reception of candidate cell SSBs. Different from the CSI reference resource, each LTM report is associated with a measurement gap for the triggered LTM report even if CSI report is configured for LTM. All the measurement resources associated with a LTM report (or a CSI report for LTM report) should be measured in a same measurement gap.

In time domain, one triggered LTM report (or a CSI report for LTM report) in uplink slot n′is associated with the latest completed measurement gap (which can also be referred to as measurement window) covering all the configured SSB resources from all candidate cells associated with the LTM report (or a CSI report for LTM report) before downlink slot

where K_offset is configured by RRC signaling;

is the subcarrier spacing configuration for K_offset;

where μ_DL and μ_UL are the subcarrier spacing configurations for DL and UL, respectively, andand are configured for UL and DL in CA (Carrier Aggregation) ;

For periodic and semi-persistent LTM reporting, if single SSB resource is configured for channel measurement, and if multiple SSB resources are configured for channel measurement,

For aperiodic LTM report, where Z’ is the minimal time requirement after the end the LTM reference and before the transmission of the PUSCH for the LTM reporting; is the number of symbols in a slot.

Figure 3 is a schematic flow chart diagram illustrating an embodiment of a method 300 according to the present application. In some embodiments, the method 300 is performed by an apparatus, such as a remote unit (e.g. UE) . In certain embodiments, the method 300 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 300 is a method performed at a UE, comprising: 302 receiving a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In some embodiment, the method further comprises receiving a cell switch command or a DCI that indicates a TCI state, wherein the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell. In particular, the method may further comprise receiving TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied. In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is received before receiving the cell switch command. Alternatively, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.

In some embodiment, the method further comprises transmitting UE capabilities including: the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.

Figure 4 is a schematic flow chart diagram illustrating an embodiment of a method 400 according to the present application. In some embodiments, the method 400 is performed by an apparatus, such as a base unit. In certain embodiments, the method 400 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 400 may comprise 402 transmitting a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In some embodiment, the method further comprises transmitting a cell switch command or a DCI that indicates a TCI state, wherein the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell. In particular, the method may further comprise transmitting TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied. In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is transmitted before transmitting the cell switch command. Alternatively, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.

In some embodiment, the method further comprises receiving UE capabilities including: the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.

Figure 5 is a schematic flow chart diagram illustrating an embodiment of a method 500 according to the present application. In some embodiments, the method 500 is performed by an apparatus, such as a remote unit (e.g. UE) . In certain embodiments, the method 500 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 500 is a method performed at a UE, comprising: 502 receiving a DCI that indicates a TCI state for a candidate cell, wherein, the UE, upon receiving a CSC to indicate the UE to handover to a target cell that is the candidate cell, handovers from a serving cell to the target cell and applies the indicated TCI state.

In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is received before receiving the CSC.

In some embodiment, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell and is received before receiving the CSC; and the DCI further includes a field to indicate the indicated TCI state is applied for the serving cell or the candidate cell.

In some embodiment, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.

In some embodiment, the DCI is received after receiving the CSC and has a CRC scrambled by a C-RNTI associated with the target cell.

In some embodiment, the method further comprises receiving TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.

Figure 6 is a schematic flow chart diagram illustrating an embodiment of a method 600 according to the present application. In some embodiments, the method 600 is performed by an apparatus, such as a base unit. In certain embodiments, the method 600 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 600 may comprise 602 transmitting a DCI that indicates a TCI state for a candidate cell, wherein, a UE, upon receiving a CSC to indicate the UE to handover to a target cell that is the candidate cell, handovers from a serving cell to the target cell and applies the indicated TCI state.

In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is transmitted before transmitted the CSC.

In some embodiment, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell and is transmitted before transmitting the CSC; and the DCI further includes a field to indicate the indicated TCI state is applied for the serving cell or the candidate cell.

In some embodiment, the DCI is transmitted after transmitting the CSC and has a CRC scrambled by a C-RNTI associated with the target cell.

In some embodiment, the method further comprises transmitting TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.

Figure 7 is a schematic flow chart diagram illustrating an embodiment of a method 700 according to the present application. In some embodiments, the method 700 is performed by an apparatus, such as a remote unit (e.g. UE) . In certain embodiments, the method 700 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 700 is a method performed at a UE, comprising: 702 determining a measurement gap associated with a LTM report, wherein, the measurement gap associated with the LTM report in uplink slot n’ is the latest measurement gap before downlink slot and 704 transmitting the LTM report in uplink slot n’ .

In some embodiment, the LTM report has higher priority than a CSI report but has lower priority than HARQ.

In some embodiment, the resources from all candidate cells associated with the LTM report are covered by a same measurement gap.

Figure 8 is a schematic flow chart diagram illustrating an embodiment of a method 800 according to the present application. In some embodiments, the method 800 is performed by an apparatus, such as a base unit. In certain embodiments, the method 800 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 800 may comprise 802 determining a measurement gap associated with a LTM report, wherein, the measurement gap associated with the LTM report in uplink slot n’is the latest measurement gap before downlink slotand 804 receiving the LTM report in uplink slot n’ .

Figure 9 is a schematic flow chart diagram illustrating an embodiment of a method 900 according to the present application. In some embodiments, the method 900 is performed by an apparatus, such as a distributed unit. In certain embodiments, the method 900 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 900 is a method performed at a first distributed unit (DU) , comprising: 902 transmitting, to a second DU, a request for TCI states configuration of at least one candidate cell belonging to the second DU; and 904 receiving, from the second DU, the requested TCI states configuration (s) .

In some embodiment, the request is also for TRS configuration for TRS configured in each TCI state of the TCI states configuration; and each requested TRS configuration is received along with the requested TCI states configuration.

In some embodiment, the method further comprises transmitting, to a UE, the requested TCI states configuration. In some embodiment, the method further comprises transmitting, to a UE, the requested TRS configuration.

Figure 10 is a schematic flow chart diagram illustrating an embodiment of a method 1000 according to the present application. In some embodiments, the method 1000 is performed by an apparatus, such as a distributed unit. In certain embodiments, the method 1000 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 1000 is a method performed at a second DU, comprising: 1002 receiving, from a first DU, a request for TCI states configuration of at least one candidate cell belonging to the second DU; and 1004 transmitting, to the first DU, the requested TCI states configuration (s) .

In some embodiment, the request is also for TRS configuration for TRS configured in each TCI state of the TCI states configuration; and each requested TRS configuration is transmitted along with the requested TCI states configuration.

Figure 11 is a schematic block diagram illustrating apparatuses according to one embodiment.

Referring to Figure 11, the UE (i.e. the remote unit) includes a processor, a memory, and a transceiver. The processor implements a function, a process, and/or a method which are proposed in Figure 3, 5 or 7.

A first UE comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to receive, via the transceiver, a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

A second UE comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to receive, via the transceiver, a DCI that indicates a TCI state for a candidate cell, wherein, the UE, upon receiving a CSC to indicate the UE to handover to a target cell that is the candidate cell, handovers from a serving cell to the target cell and applies the indicated TCI state.

In some embodiment, the processor is further configured to receive, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.

A third UE comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to determine a measurement gap associated with a LTM report, wherein, the measurement gap associated with the LTM report in uplink slot n’ is the latest measurement gap before downlink slotand transmit, via the transceiver, the LTM report in uplink slot n’ .

The gNB (i.e. the base unit) includes a processor, a memory, and a transceiver. The processor implements a function, a process, and/or a method which are proposed in Figure 4, 6 or 8.

A first base unit comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to transmit, via the transceiver, a MAC CE for activating TCI states, wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.

In some embodiment, the processor is further configured to transmit, via the transceiver, a cell switch command or a DCI that indicates a TCI state, wherein, the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell. In some embodiment, the processor is further configured to transmit, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied. In some embodiment, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is transmitted before transmitting the cell switch command. Alternatively, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.

In some embodiment, the processor is further configured to receive, via the transceiver, UE capabilities including: the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.

A second base unit comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to transmit, via the transceiver, a DCI that indicates a TCI state for a candidate cell, wherein, a UE, upon receiving a CSC to indicate the UE to handover to a target cell that is the candidate cell, handovers from a serving cell to the target cell and applies the indicated TCI state.

In some embodiment, the processor is further configured to transmit, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.

A third base unit comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to determine a measurement gap associated with a LTM report, wherein, the measurement gap associated with the LTM report in uplink slot n’ is the latest measurement gap before downlink slotand receive, via the transceiver, the LTM report in uplink slot n’ .

Figure 12 is a schematic block diagram illustrating a base unit (e.g., gNB) has CU-DU split structure. Referring to Figure 12, a gNB includes a gNB-CU and two gNB-DUs (i.e., a first DU (gNB-DU#1) and a second DU (gNB-DU#2) ) . Each of the first DU and the second DU includes a processor, a memory, and a transceiver. The processor in the first DU implements a function, a process, and/or a method which are proposed in Figure 9.

The first DU comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to transmit, via the transceiver, to a second DU, a request for TCI states configuration of at least one candidate cell belonging to the second DU; and receive, via the transceiver, from the second DU, the requested TCI states configuration (s) .

In some embodiment, the processor is further configured to transmit, via the transceiver, to a UE, the requested TCI states configuration. In some embodiment, the processor is further configured to transmit, via the transceiver, to a UE, the requested TRS configuration.

The processor in the second DU implements a function, a process, and/or a method which are proposed in Figure 10.

The second DU comprises a transceiver; and a processor coupled to the transceiver, wherein the processor is configured to receive, via the transceiver, from a first DU, a request for TCI states configuration of at least one candidate cell belonging to the second DU; and transmit, via the transceiver, to the first DU, the requested TCI states configuration (s) .

Layers of a radio interface protocol may be implemented by the processors. The memories are connected with the processors to store various pieces of information for driving the processors. The transceivers are connected with the processors to transmit and/or receive a radio signal. Needless to say, the transceiver may be implemented as a transmitter to transmit the radio signal and a receiver to receive the radio signal.

The memories may be positioned inside or outside the processors and connected with the processors by various well-known means.

In the embodiments described above, the components and the features of the embodiments are combined in a predetermined form. Each component or feature should be considered as an option unless otherwise expressly stated. Each component or feature may be implemented not to be associated with other components or features. Further, the embodiment may be configured by associating some components and/or features. The order of the operations described in the embodiments may be changed. Some components or features of any embodiment may be included in another embodiment or replaced with the component and the feature corresponding to another embodiment. It is apparent that the claims that are not expressly cited in the claims are combined to form an embodiment or be included in a new claim.

The embodiments may be implemented by hardware, firmware, software, or combinations thereof. In the case of implementation by hardware, according to hardware implementation, the exemplary embodiment described herein may be implemented by using one or more application-specific integrated circuits (ASICs) , digital signal processors (DSPs) , digital signal processing devices (DSPDs) , programmable logic devices (PLDs) , field programmable gate arrays (FPGAs) , processors, controllers, micro-controllers, microprocessors, and the like.

Embodiments may be practiced in other specific forms. The described embodiments are to be considered in all respects to be only illustrative and not restrictive. The scope of the invention is, therefore, indicated in the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

A user equipment (UE) , comprising:

a transceiver; and

a processor coupled to the transceiver, wherein the processor is configured to

receive, via the transceiver, a MAC CE for activating TCI states,

wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated.
The UE of claim 1, wherein,

the processor is further configured to receive, via the transceiver, a cell switch command or a DCI that indicates a TCI state, wherein, the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell.
The UE of claim 1, wherein,

the MAC CE includes a BWP ID field to indicate the initial BWP when the candidate cell is indicated as a target cell.
The UE of claim 1, wherein,

the processor is further configured to transmit, via the transceiver, UE capabilities including:

the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and

the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.
The UE of claim 2, wherein, the processor is further configured to

receive, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.
The UE of claim 2, wherein, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is received before receiving the cell switch command.
The UE of claim 2, wherein, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.
A method performed at a user equipment (UE) , comprising:

receiving a MAC CE for activating TCI states,

wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated
A base unit, comprising:

a transceiver; and

a processor coupled to the transceiver, wherein the processor is configured to

transmit, via the transceiver, a MAC CE for activating TCI states,

wherein the MAC CE includes a field to indicate the TCI states of a serving cell or of a candidate cell are activated
The base unit of claim 9, wherein, the processor is further configured to

transmit, via the transceiver, a cell switch command or a DCI that indicates a TCI state,

wherein, the indicated TCI state is one or two of the activated TCI states for the candidate cell that is indicated as a target cell
The base unit of claim 9, wherein, the MAC CE includes a BWP ID field to indicate the initial BWP when the candidate cell is indicated as a target cell.
The base unit of claim 9, wherein, the processor is further configured to

receive, via the transceiver, UE capabilities including:

the maximum number of activated TCI states and maximum number of indicated TCI states for all candidate cells configured in the serving cell; and

the maximum number of candidate cells for early TCI state activation and indication configured in the serving cell.
The base unit of claim 10, wherein, the processor is further configured to

transmit, via the transceiver, TRS configured in the indicated TCI state of the candidate cell after the indicated TCI state is applied.
The base unit of claim 10, wherein, the DCI has a CRC scrambled by a dedicated configured RNTI associated with the candidate cell and is received before receiving the cell switch command.
The base unit of claim 10, wherein, the DCI has a CRC scrambled by a C-RNTI associated with the serving cell, and the DCI further includes a field to indicate a candidate cell index associated with the candidate cell.