Measurements for cell switch

Abstract

An apparatus and method for measurement reporting during cell transitions are disclosed. A first apparatus, such as a user equipment (UE), acquires a control policy and detects a collection of reference signal (RS) identifiers from a second apparatus, such as a base station. The apparatus isolates a CSI-RS pertaining to a serving cell—specifically a PCell or PSCell—using the spatial correlation of a linked Synchronization Signal Block (SSB). This isolation process involves detecting a quasi-co-located (QCL) relationship and validating that the SSB frequency aligns with a reference frequency or absolute coordinate. Spatial parameter metadata or TCI states are used to identify the linked SSB. The apparatus relays measured values or resource indices for the isolated CSI-RS to the base station as dictated by the control policy.

Description

MEASUREMENTS FOR CELL SWITCHFIELD

[0001] Various example embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for measurements for the cell switch.BACKGROUND

[0002] Layer 1 (LI) / Layer 1 (L2) Triggered Mobility (LTM) is a procedure in which a network device receives LI / Layer 1 (L3) measurement report(s) from a user device, and on their basis the network device changes a serving cell of the user device by a cell switch command signaled via a medium access control -control element (MAC-CE).

[0003] The cell switch command may indicate an LTM candidate cell configuration that the network device previously prepared and provided to the user device through a radio resource control (RRC) signaling. Then the user device switches to the target cell according to the cell switch command. The LTM procedure can be used to reduce the mobility latency and interruption caused by the mobility.SUMMARY

[0004] In a first aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: receive, from a second apparatus, a reporting configuration associated with a cell switch operation; receive, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; determine, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point; and report, to the second apparatus for the cell switch operation based on the reportingconfiguration, a measurement at least associated with the determined CSI-RS.

[0005] In a second aspect of the present disclosure, there is provided a method. The method comprises: receiving a reporting configuration from a second apparatus; receiving, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; determining, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point; and reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0006] In a third aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for receiving a reporting configuration from a second apparatus; means for receiving, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; means for determining, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point; and means for reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0007] In a fourth aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the second aspect.

[0008] It is to be understood that the Summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Some example embodiments will now be described with reference to the accompanying drawings, where:

[0010] FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

[0011] FIG. 2 illustrates an example signalling procedure for LTM;

[0012] FIG. 3 illustrates an example reporting configuration for measurement resources from LTM candidate cells;

[0013] FIG. 4 illustrates a signaling chart for communication according to some example embodiments of the present disclosure;

[0014] FIG. 5 illustrates a signaling chart for communication according to some example embodiments of the present disclosure;

[0015] FIG. 6 illustrates a signaling chart for communication according to some example embodiments of the present disclosure;

[0016] FIG. 7 illustrates a signaling chart for communication according to some example embodiments of the present disclosure;

[0017] FIG. 8 illustrates a signaling chart for communication according to some example embodiments of the present disclosure;

[0018] FIG. 9 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0019] FIG. 10 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0020] FIG. 11 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0021] FIG. 12 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0022] FIG. 13 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

[0023] FIG. 14 illustrates a block diagram of an example computer readable medium inaccordance with some example embodiments of the present disclosure.

[0024] Throughout the drawings, the same or similar reference numerals represent the same or similar element.DETAILED DESCRIPTION

[0025] Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

[0026] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0027] References in the present disclosure to “one embodiment,” “an embodiment,” “an example embodiment,” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0028] It shall be understood that although the terms “first,” “second,”..., etc. in front of noun(s) and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another and they do not limit the order of the noun(s). For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0029] As used herein, “at least one of the following: ”and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0030] As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and / or “including”, when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0032] As used in this application, the term “circuitry” may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analog and / or digital hardware circuit(s) with software / firmware and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0033] This definition of circuitry applies to all uses of this term in this application,including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0034] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), 5.5G, the sixth generation (6G) communication protocols, and / or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0035] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, radio access network (RAN) split architecture comprises a Centralized Unit (CU) and a Distributed Unit (DU) at anIAB donor node. An IAB node comprises a Mobile Terminal (IAB-MT) part that behaves like a UE toward the parent node, and a DU part of an IAB node behaves like a base station toward the next-hop IAB node.

[0036] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT). The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node). In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0037] As used herein, the term “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other combination of the time, frequency, space and / or code domain resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resourcesin other domains.

[0038] Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It is noted that the following accompanying drawings may be implemented separately or in any suitable combination, which is not limited in the present disclosure.

[0039] FIG. 1 illustrates an example communication network 100 in which example embodiments of the present disclosure can be implemented. As shown in FIG. 1, the communication network 100 may comprise a first apparatus 110 which may also be, for example, referred to as a terminal device or a UE.

[0040] The communication network 100 may further comprise a second apparatus 120, which may be, for example, considered as being a network device or being included in a network device. In some example embodiments, the network device may be discussed as a BS, a gNB, or an eNB.

[0041] A serving area provided by the second apparatus 120 is called a cell. The second apparatus 120 may provide one or more cells serving the first apparatus. For example, the first apparatus 110 may communicate with the second apparatus 120 within the cell 102. In some scenarios, the cell 102 may be considered as a cell that is serving the first apparatus 110.

[0042] In the following, for the purpose of illustration, some example embodiments are described with the first apparatus 110 operating as a terminal device and the second apparatus 120 operating as a network device. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0043] In some example embodiments, if the first apparatus 110 is a terminal device and second apparatus 120 is a network device, a link from the second apparatus 120 to first apparatus 110 is referred to as a downlink (DL), while a link from the first apparatus 110 to second apparatus 120 is referred to as an UL. In DL, the second apparatus 120 is a transmitting (TX) apparatus (or a transmitter) and the first apparatus 110 is a receiving (RX) apparatus (or a receiver). In UL, the first apparatus 110 is a TX apparatus (or a transmitter) and the second apparatus 120 is an RX apparatus (or a receiver).

[0044] It is to be understood that the number of devices and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of devices configured to implementing example embodiments of the present disclosure. Although not shown, it would be appreciated that one or more additional devices may be located in the cell 102, and one or more additional cells may be deployed in the communication environment 100. It is noted that although illustrated as a network device, the network device 120 may be another device than a network device. Although illustrated as a terminal device, the terminal device 110 may be another device than a terminal device.

[0045] In the following, for the purpose of illustration, some example embodiments are described with the terminal device 110 operating as a UE and the network device 120 operating as a base station. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0046] Communications in the communication environment 100 may be implemented according to any proper communication protocol(s), comprising, but not limited to, cellular communication protocols of the first generation (1G), the second generation (2G), the third generation (3G), the fourth generation (4G), the fifth generation (5G), the sixth generation (6G), and the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple (OFDM), Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and / or any other technologies currently known or to be developed in the future.

[0047] LTM is a cell switch procedure, where UE’s serving cell (PCell or PSCell) may be switched by the network by sending an LTM cell switch command. An LTM switch command may be assumed delivered by a MAC signaling using a MAC CE. Hence, not using an RRC signaling as an L3 based handover which is one of the current methods forchanging between cells. An LTM cell switch decision may be based on measurements (for example LI measurements) that are performed and reported (for example LI measurement report) by the UE. Measurements and reporting may be based on an LTM candidate cell configuration provided by the network for one or more LTM candidate cells. An LTM candidate cell may be neighboring cells or a current serving cells of UE (e.g., one of the current secondary cell).

[0048] LTM measurements on a neighboring candidate cell may be performed using SSBs transmitted by the candidate cell for which the SSB configuration is provided to the UE.

[0049] Before the cell switch, network (NW) may activate one or more transmission configuration indicator (TCI) state(s) for one or more candidate cells for early DL synchronization. Once a candidate cell TCI state is activated, the UE may start tracking the downlink time / frequency synchronization using the reference signals associated with the activated TCI state(s). The UE may also perform early UL synchronization before the cell switch if this is requested by the network.

[0050] FIG. 2 illustrates an example signalling procedure for an LTM procedure, which may comprise the following steps:

[0051] 1 : The UE 110 sends a MeasurementReport message to the gNB 120. The gNB 120 decides to configure LTM and initiates LTM preparation.

[0052] 2 : The gNB 120 transmits an RRCReconfiguration message to the UE 110 including the LTM candidate configurations.

[0053] 3 : The UE 110 stores the LTM candidate configurations and transmits an RRCReconfigurationComplete message to the gNB 120.

[0054] 4a: The UE 110 performs DL synchronization with the candidate cell(s) (via early TCI activation) before receiving the cell switch command.

[0055] 4b: The UE 110 performs early TA acquisition with the candidate cell(s) as requested by the network before receiving the cell switch command. This may be done via contention free random access (CFRA) triggered by a physical downlink control channel (PDCCH) order from the source cell, following which the UE 110 sends preamble towards the indicated candidate cell.

[0056] In order to minimize the data interruption of the source cell due to CFRA towards the candidate cell(s), the UE 110 may not receive random access response from the network for the purpose of TA value acquisition and the TA value of the candidate cell is indicated in the cell switch command. The UE 110 may not maintain the TA timer for the candidate cell and relies on network implementation to guarantee the TA validity.

[0057] 5 : The UE 110 performs LI measurements on the configured candidate cell(s) and transmits LI measurement reports to the gNB 120. LI measurement may be performed as long as RRC reconfiguration (step 2) is applicable.

[0058] 6 : The gNB 120 decides to execute cell switch to a target cell and transmits a cell switch command MAC CE triggering cell switch by including the candidate configuration index of the target cell. The UE 110 switches to the target cell and applies the configuration indicated by candidate configuration index.

[0059] 7 : The UE 110 performs the random-access procedure towards the target cell, if UE 110 does not have valid TA of the target cell.

[0060] 8 : The UE 110 completes the LTM cell switch procedure by sending RRCReconfigurationComplete message to target cell. For random access channel (RACH)-based LTM, if the UE 110 has performed a RA procedure in step 7 the UE 110 considers that LTM cell switch execution is successfully completed when the randomaccess procedure is successfully completed.

[0061] For RACH-less LTM, the UE 110 considers that LTM cell switch execution is successfully completed when the UE 110 determines that the network has successfully received its first UL data. The steps 4-8 may be performed multiple times for subsequent LTM using the LTM candidate configuration(s) provided in step 2.

[0062] For cell switch procedures, such as in LTM, the UE may be configured to report LI measurements, like LI -reference signal received power (RSRP) or LI -signal to interference plus noise ratio (SINR), associated with candidate cells. These measurements help the network (e.g., the current serving or source cell) prepare for a cell switch, for example, by triggering early downlink synchronization (i.e., TCI state activation) and / or early uplink synchronization (i.e., TA acquisition) with one or more candidate cells, or by selecting a candidate cell for the switch.

[0063] For the LTM, information about measurement resources (e.g., SSBs or CSI-RSs) from LTM candidate cells may be provided to the UE so that UE may perform measurements. The UE may also be configured with LI measurement reporting configuration where the UE may report the measurements. For the LTM, periodic and semi -persistent report on physical uplink control channel (PUCCH), semi-persistent report on physical uplink shared channel (PUSCH), and aperiodic report on PUSCH are supported. Additionally, event triggered reporting using MAC-CE may also be supported.

[0064] FIG. 3 illustrates an example reporting configuration for measurement resources from LTM candidate cells. As shown in FIG. 3, the UE may be configured with one or more LTM CSI reporting configurations (e.g., LTM-CSI-ReportConfig 310) where each reporting configuration contains an LTM CSI resource configuration (LTM-CSI-ResourceConfig 320) containing the information of resources to be used for channel measurements (Ll-RSRP measurements). An LTM resource configuration may contain SSBs from one or more candidate cells. For each reporting configuration, the UE may be configured to report M beams from each of the L configured candidate cells, i.e., each LTM CSI Resource Setting (LTM-CSI-ResourceConfig 310) may contain a configuration of a LTM-CSLSSB-ResourceSet 330 which comprises of a list of Z > 1 SS / PBCH(SSB) blocks indices (given by Itm-CSI-SSB-ResourceList 340) and a list of Z LTM-Candidatelds (given by Itm-CandidatelDList 350) referring to candidate cells associated with the SS / PBCH block indices.

[0065] For each candidate cell, the UE determines the time domain behavior of a SS / PBCH block resource from s sb -Periodicity and ssb-PositionsInBurst and the frequency domain behavior of a SS / PBCH block resource is determined by the higher layer parameters subCarrierSpacing, ssbFrequency.- For each cell, LTM CSI Report Configurations are given under current serving cell’s configuration where each report configuration contains an indication of an LTM CSI Resource Config and other parameters related for reporting, e.g., timing and uplink resources to transmit reports.- An LTM CSI Resource configuration may contain a set of SSB indices from multiple candidate cells. This is placed in a common LTM configuration, i.e., in LTM-Config. - The detailed configuration of each SSB of a candidate cell indicated in an LTM CSIResource configuration given in LTM-SSB-Config under LTM-Candidate IE. For each candidate cell, LTM-Candidate IE contains the configuration / information which is needed by the UE before the cell switch, e.g., SSB information for LTM measurements.- An LTM-Candidate IE also includes an RRC container (ServingCellConfig) which contains all the configuration details that will be needed by the UE after UE moves to this candidate cell after the cell switch from the current serving cell. In other words, ServingCellConfig given under LTM-Candidate IE contains the configuration details needed to perform regular serving cell operation within the candidate cell.

[0066] Descriptions of fields in LTM-CSI-ReportConfig, LTM-ReportContent, LTM-CSLResourceConfig, LTM-CSI-SSB-ResourceSet are listed in Tables as below:_ LTM-CSI-ReportConfig field descriptions _Itm-CSI-ReportConfigldThis field is used to identify an LTM-CSI-ReportConfig. _Itm-ReportContentThis field defines the content of the LTM LI measurement report. _Itm-ResourcesForChannelMeasurementThis field indicates the resources used for LTM LI measurements. _pucch-CSI-ResourceListIndicates which PUCCH resource to use for reporting on PUCCH, _reportConfigTypeThis field describes the time domain behaviour of how the LI measurements for LTM are reported. _reportSlotConfigPeriodicity and slot offset (see TS 38,214

[0019] , clause 5,2, 1,4), _reportSlotOffsetList, reportSlotOffsetListDCI-O-1 , reports lotOffsetListDCI-O-2Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting._ LTM-ReportContent field descriptions _nrOfReportedCellsThis field defines how many cells are reported within a single LI measurement report instance. nrOfReportedRS-PerCellThis field defines how many RSs per cell are reported within a single LI measurement report instance. _spCelllnclusionThis field indicates whether the UE shall include a LI measurement report associated to the current SpCell. This field can only be configured if the current SpCell is configured as an LTMcandidate cell._ LTM-CSI-ResourceConfig field descriptions _Itm-CSI-ResourceConfigldThis field is used to identify an instance o£ LTM-CSI-ResourceConfig IE, _Itm-CSI-SSB-ResourceSetThis field defines one SS / PBCH block resource set from one or more LTM candidate cells.LTM-CSI-SSB-ResourceSet field descriptionsItm-CandidateldListThis field Indicates the LTM candidate cell IDs related to the SSBs in the Itm-CSI-SSB- ResourceList. The list has the same number of entries as Itm-CSI-SSB-ResourceList.Itm-CSI-SSB-ResourceListThis field is used to indicate on SS / PBCH block resources from one or more LTM candidate cells.Itm-CSI-SSB-ResourceSetldThis field is used to idenfity on SS / PBCH block resource set.

[0067] For LI measurements, the UE may be typically configured with one or more reporting configurations, each associated with a measurement set that specifies which RSs to measure. The UE may measure the configured RSs and select a certain number (as defined in the reporting configuration) for reporting. The selection process may be generally left to UE implementation.

[0068] In some cases, the UE may be configured to report measurements for the current serving cell, e.g., the current special cell (SpCell) or primary cell (PCell) of the Master Cell Group (MCG) or the Cecondary Cell Group (SCG), alongside candidate cells. For the LTM, this is done by setting SpCelllnclusion = true. When enabled, the UE may include a configured number of measurements from the current serving cell (SpCell) in its report. It is expected that the measurement RSs for the current SpCell may be part of the overall measurement RS set (e.g., LTM-CSI-ResourceConfig) along with RSs from other candidate cells.

[0069] Since the measurement RS set may include RSs from multiple candidate cells, the UE needs to clearly identify RSs belonging to the current SpCell for accurate reporting. For SSB-based measurements, by using both PCI (cell ID) and frequency information, if spCelllnclusion is configured, the SSB resources in Itm-CSI-SSB-ResourceList associated with the current SpCell are identified as entries where the PCI (from Itm-CandidatePCI) and the frequency (from ssb-Frequency) match the PCI and center frequency of the celldefining SSB of the current SpCell, as indicated by the corresponding Itm-Candidateld entry in Itm-CandidateldList.

[0070] If a UE is configured with a Itm-CSI-ReportConfig, and if the UE is configured with spCelllnclusion, the UE may report in a single reporting instance nrOfReportedRS-PerCell different SSBRI for the current SpCell and each of the nrOfReportedCells -1 candidate cells.

[0071] Otherwise, the UE may report in a single reporting instance nrOfReportedRS-PerCell different SSBRI for each of the nrOfReportedCells candidate cells. The SSBRI k (k > 0) may correspond to the configured (k+l)-th entry of the associated Itm-CSI-SSB-ResourceList in the corresponding Itm-CSI-SSB-ResourceSet.

[0072] if spCelllnclusion is configured, SSB resources in Itm-CSI-SSB-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (given by ssb -Frequency) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of cell-defining SSB of the current SpCell.

[0073] LTM may offer improvements in handover latency and interruption time compared to Layer 3 based mobility. However, LTM may also have a number of limitations compared to Layer 3 mobility.

[0074] Therefore, a number of these limitations are expected to be removed where one of the objectives is to support CSI-RS based LI measurements on candidate cells. In this case, mobility enhancements may comprise specifying support for CSI-RS measurements for LTM procedures and enable CSI-RS based beam management.

[0075] It is still unclear which frequency information is to be used to determine which CSLRS(s) from a measurement RS set, configured for cell switch (e.g., LTM) measurements, belongs to the current SpCell.

[0076] Furthermore, for S SB-based measurements, when SPCelllnclusion is configured, both the PCI (cell ID) and the frequency of an SSB are used to determine the SSBs of the current SpCell from the measurement set (which includes RSs from one or more candidate cells). Specifically, an SSB is considered to belong to the current SpCell only if its PCI and ssb-Frequency match the PCI and center frequency of the cell-defining SSB of the current SpCell.

[0077] The reason for using frequency information in addition to the cell ID is that the same PCI can be reused by two different cells, especially when they operate on different carrier frequencies. Since SSB frequency locations are typically determined associated with the carrier frequency, two cells with the same PCI but different frequencies will have distinct SSB frequency locations. This helps to avoid collisions in synchronization signal transmissions.

[0078] For SSBs, one cell-defining SSB (e.g., in FR1) or one set of cell-defining SSBs (e.g., for different beams in FR2) is used per cell, and it’s typically always active (or considered as cell-specific signals).

[0079] For each SSB, the frequency (or center frequency) is clearly defined, either by: -absoluteFrequencySSB in ServingCellConfigCommon —> DownlinkConfigCommon —> Frequency InfoDL when the UE switches to a cell due to RRC Reconfiguration with sync, or-Information in ServingCellConfigCommonSIB — DownlinkConfigCommonSIB — FrequencylnfoDL-SIB, such as offsetToPointA (representing the frequency offset between Point A (lowest subcarrier) and the lowest subcarrier of the lowest resource block overlapping with the SS / PBCH block).

[0080] For an LTM candidate cell, the SSB frequency is explicitly provided in LTM-Candidate LTM-SSB-Config ssb -Frequency.

[0081] For CSI-RS-based measurements, multiple CSI-RSs may be configured in a cell, and different sets of UE-specific CSI-RSs may be assigned to different UEs. There is no specific frequency parameter for a CSI-RS. Instead, its frequency is typically determined by the starting resource block (given by startingRB in CSI-FrequencyOccupation) relative to the common reference point for the resource block grid (Point A) and the number of allocated resource blocks (given by nrofRBs in CSI-FrequencyOccupation).

[0082] The CSI-RSs configured for LTM (as an LTM candidate cell, e.g., in LTM-Candidate IE) may differ from the CSI-RSs configured for serving cell procedures in the current SpCell. In other words, there may be scenarios when a CSI-RS configured for LTM measurement does not have any associated CSI-RS configured for serving cell measurement.

[0083] Therefore, when SPCelllnclusion is configured, it is unclear which frequency information should be used to determine which CSI-RSs from a measurement RS set, configured for cell switch (e.g., LTM) measurements, belong to the current SpCell.

[0084] The solutions proposed in the present disclosure are presented in the context of LTM; however, the proposed solutions are not limited to LTM alone and are applicable to other mobility, handover, or cell switch procedures such as L3 handover or any othercell switch procedure where the procedure is performed using procedures at one or more layers from LI, L2, and L3.

[0085] In accordance with some example embodiments of the present disclosure, there is provided a solution for measurements for the cell switch. In this solution, the first apparatus receives, from a second apparatus, a configuration of a measurement RS set associated with the cell switch operation and determines a CSI-RS associated with a serving cell of the first apparatus from the measurement RS set based at least on an association of an SSB associated with the CSI-RS. The first apparatus reports, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0086] Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0087] Reference is now made to FIG. 4, which shows a signaling chart 400 of communication according to some example embodiments of the present disclosure. As shown in FIG. 4, the signaling chart 400 involves a first apparatus 110 and a second apparatus 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 400.

[0088] As shown in FIG. 4, the first apparatus 110 may receive (405) a reporting configuration associated with a cell switch operation from a second apparatus 120. For example, the reporting configuration may be referred to as a CSI report configuration, e.g., LTM-CSI-ReportConfig.

[0089] The first apparatus 110 may also receive (410) a configuration of measurement RS set, which may be referred to measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList, Itm-CSI-RS-ResourceSet, Itm-CSI-NZP-CSI-RS-ResourceList, or Itm-CSI-NZP-CSI-RS-ResourceSet.

[0090] The reporting configuration, e.g., LTM-CSI-ReportConfig, may be associated with a measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceSet or Itm-CSI-RS-ResourceSet.

[0091] The reporting configuration, e.g., LTM-CSI-ReportConfig, may contain a configuration of report quantity set, e.g., reportQuantity, set to 'cri-RSRP’ torequest / command the UE to report Ll-RSRP and CSI-RS resource indicator (CRI) for one or more CSI-RSs.

[0092] Then the first apparatus 110 may determine (415) a CSI-RS associated with a serving cell of the first apparatus 110 from the received measurement RS set based at least on an association of an SSB associated with the CSI-RS.

[0093] That is, the association between the CSI-RS entry in the measurement RS set and the current serving cell of the first apparatus 110 (e.g., SpCell) may be determined based on the information of the SSB linked to the CSI-RS. The serving cell used hereinafter may be referred to as a Special cell (SpCell), which may comprise a primary cell of the first apparatus 110 or at least one primary secondary cell of the first apparatus 110. This may be a primary cell or at least one primary secondary cell of MCG or SCG of the first apparatus 110.

[0094] In some example embodiments, the association may be indicated in quasi-colocated (QCL) information that is associated with the CSI-RS. That is, the SSB QCLed with the CSI-RS may be used to establish the association.

[0095] For example, the SSB associated with the CSI-RS may be identified using the QCL information (e.g., qcl-InfoPeriodicCSI-RS, qcl-info). As an option, an SSB ID may be directly provided in the QCL information. As another option, it may be derived from a TCI state ID specified in the QCL information, which may reference the SSB associated with that TCI state.

[0096] Furthermore, upon determining the SSB associated with the CSI-RS, The first apparatus 110 may compare a frequency of the SSB (e.g., given by ssb-Frequency) associated with the CSI-RS with a further frequency of a further SSB from the current serving cell (e.g., SpCell). Based on the comparison of a frequency of the SSB with a further frequency of a further SSB associated with the serving cell, if the frequency matches the further frequency the first apparatus 110 may determine the CSI-RS is associated with the serving cell. In some cases, additional condition matching the cell IDs may be applied. Based on the comparison of a frequency of the SSB with a further frequency of a further SSB associated with the serving cell, if the frequency matches the further frequency, and a cell ID of a candidate cell associated with the CSI-RS matches a further cell ID of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0097] In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList).In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.

[0098] In some example embodiments, the further frequency (i.e., frequency of the further SSB associated with the serving cell) may refer to a center frequency of a celldefining SSB or an absolute frequency SSB of the serving cell.

[0099] Then the first apparatus 110 may report (420), to the second apparatus 120 based on the reporting configuration for the cell switch operation, a measurement at least associated with the determined CSI-RS. For example, the measurement may comprise a RSRP measurement, a SINR measurement and / or a SNR measurement. The first apparatus 110 may also measure, in addition to the determined CSI-RS associated with the serving cell, at least one other CSI-RS associated with at least one other candidate cell.

[0100] For example, if the reporting configuration indicates a measurement of at least one CSI-RS associated with the serving cell is to be reported, the first apparatus 110 may report, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0101] Reference is now made to FIG. 5, which shows a signaling chart 500 of communication according to some example embodiments of the present disclosure. As shown in FIG. 5, the signaling chart 500 involves a first apparatus 110 and a second apparatus 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 500.

[0102] As shown in FIG. 5, the first apparatus 110 may receive (505) a reporting configuration associated with a cell switch operation from a second apparatus 120. For example, the reporting configuration may be referred to as a CSI report configuration, e.g., LTM-CSI-ReportConfig.

[0103] The first apparatus 110 may also receive (510) a configuration of measurement RS set, which may be referred to measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList, Itm-CSI-RS-ResourceSet, Itm-CSI-NZP-CSI-RS-ResourceList, or Itm-CSI-NZP-CSI-RS-ResourceSet.

[0104] The reporting configuration, e.g., LTM-CSI-ReportConfig, may be associated with a measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceSet or Itm-CSI-RS-ResourceSet.

[0105] The reporting configuration, e.g., LTM-CSI-ReportConfig, may contain a configuration of report quantity set, e.g., reportQuantity, set to 'cri-RSRP’ to request / command the UE to report Ll-RSRP and CSI-RS resource indicator (CRI) for one or more CSI-RSs.

[0106] Then the first apparatus 110 may determine (515) a CSI-RS associated with a serving cell of the first apparatus 110 from the received measurement RS set based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point. The serving cell used hereinafter may be referred to as a Special cell (SpCell), which may comprise a primary cell of the first apparatus 110 or at least one primary secondary cell of the first apparatus 110. This may be a primary cell or at least one primary secondary cell of MCG or SCG of the first apparatus 110.

[0107] The absolute frequency point of the CSI-RS used hereinafter may be referred to the absolute frequency point A, which indicates an absolute frequency of a reference resource block (RB) (e.g., Common RB 0). The lowest subcarrier of this RB may be known as Point A. This frequency may be combined with the starting RB (relative to Point A) to identify the starting frequency of the CSI-RS.

[0108] That is, in this solution, the absolute frequency point A configured for a CSI-RS in the measurement RS set may be used to determine its association with the current serving cell.

[0109] If the first apparatus 110 determines that an absolute frequency point of a CSI-RS in the measurement RS set matches the further absolute frequency point of the servingcell or the frequency corresponding to the further absolute frequency point, the first apparatus 110 may determine the CSI-RS is associated with the serving cell. In some cases, additional condition matching the cell IDs may be applied. If the first apparatus 110 determines that an absolute frequency point of a CSI-RS in the measurement RS set matches the further absolute frequency point of the serving cell or the frequency corresponding to the further absolute frequency point and a cell ID of a candidate cell associated with the CSI-RS matches a further cell ID of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0110] In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList).In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.[OHl] For example, the absolute frequency point A of the CSI-RS from the measurement RS set may be compared with the absolute frequency point A (provided in Frequency InfoDL) or the frequency corresponding to Point A of the current serving cell (e.g., SpCell).

[0112] Then the first apparatus 110 may report (520), to the second apparatus 120 based on the reporting configuration for the cell switch operation, a measurement at least associated with the determined CSI-RS. For example, the measurement may comprise a RSRP measurement, a SINR measurement and / or a SNR measurement. The first apparatus 110 may also measure, in addition to the determined CSI-RS associated with the serving cell, at least one other CSI-RS associated with at least one other candidate cell.

[0113] For example, if the reporting configuration indicates a measurement of at least one CSI-RS associated with the serving cell is to be reported, the first apparatus 110 mayreport, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0114] Reference is now made to FIG. 6, which shows a signaling chart 600 of communication according to some example embodiments of the present disclosure. As shown in FIG. 6, the signaling chart 600 involves a first apparatus 110 and a second apparatus 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 600.

[0115] As shown in FIG. 6, the first apparatus 110 may receive (605) a reporting configuration associated with a cell switch operation from a second apparatus 120. For example, the reporting configuration may be referred to as a CSI report configuration, e.g., LTM-CSI-ReportConfig.

[0116] The first apparatus 110 may also receive (610) a configuration of measurement RS set, which may be referred to measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList, Itm-CSI-RS-ResourceSet, Itm-CSI-NZP-CSI-RS-ResourceList, or Itm-CSI-NZP-CSI-RS-ResourceSet.

[0117] The reporting configuration, e.g., LTM-CSI-ReportConfig, may be associated with a measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceSet or Itm-CSI-RS-ResourceSet.

[0118] The reporting configuration, e.g., LTM-CSI-ReportConfig, may contain a configuration of report quantity set, e.g., reportQuantity, set to 'cri-RSRP’ to request / command the UE to report Ll-RSRP and CSI-RS resource indicator (CRI) for one or more CSI-RSs.

[0119] Then the first apparatus 110 may determine (615) a CSI-RS associated with a serving cell of the first apparatus 110 from the received measurement RS set based on a comparison of respective frequencies of starting RBs of one or more CSI-RSs in the measurement RS set with respective further frequencies of further starting RBs of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific SSB of the serving cell.

[0120] That is, a frequency of the starting RB configured for a CSI-RS in the measurement RS set may be used to determine its association with the current serving cell.

[0121] In this case, the frequency of the starting RB of the CSI-RS from the measurement RS set may be compared with the frequencies of the starting resource blocks associated with the CSI-RS s configured in the current serving cell.

[0122] If the first apparatus 110 determines a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell. In some cases, additional condition matching the cell IDs may be applied. If the first apparatus 110 determines a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in the serving cell and a cell ID of a candidate cell associated with the CSI-RS matches a further cell ID of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0123] In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList).

[0124] In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.

[0125] In other words, if the frequency of a starting RB of a CSI-RS from the measurement RS set is the same as the frequency of a starting RB of any CSI-RS configured in the current serving cell, the CSI-RS may be considered associated with the current serving cell. Additional condition matching the cell IDs may be applied.

[0126] In some example embodiments, if the frequency of the starting RB of the CSI-RS in the measurement RS set matches the further frequency of the further starting RB of the further CSI-RS configured in a current active bandwidth part (BWP) in the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0127] In some other example embodiments, if the frequency of the starting RB of the CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB oran absolute frequency SSB of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0128] In some other example embodiments, if the frequency of the starting RB of the CSI-RS in the measurement RS set matches the further frequency of the further starting RB of the further CSI-RS configured in the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0129] The cell ID condition may also be considered for all options as described above. The cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList). In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.

[0130] Then the first apparatus 110 may report (620), to the second apparatus 120 based on the reporting configuration for the cell switch operation, a measurement at least associated with the determined CSI-RS. For example, the measurement may comprise a RSRP measurement, a SINR measurement and / or a SNR measurement. The first apparatus 110 may also measure, in addition to the determined CSI-RS associated with the serving cell, at least one other CSI-RS associated with at least one other candidate cell.

[0131] For example, if the reporting configuration indicates a measurement of at least one CSI-RS associated with the serving cell is to be reported, the first apparatus 110 may report, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0132] Reference is now made to FIG. 7, which shows a signaling chart 700 of communication according to some example embodiments of the present disclosure. As shown in FIG. 7, the signaling chart 700 involves a first apparatus 110 and a second apparatus 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 700.

[0133] As shown in FIG. 7, the first apparatus 110 may receive (705) a reporting configuration associated with a cell switch operation from a second apparatus 120. For example, the reporting configuration may be referred to as a CSI report configuration, e.g., LTM-CSI-ReportConfig.

[0134] The first apparatus 110 may also receive (710) a configuration of measurement RS set, which may be referred to measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceSet or Itm-CSI-RS-ResourceSet.

[0135] The reporting configuration, e.g., LTM-CSI-ReportConfig, may be associated with a measurement CSI-RS set or a CSI-RS resource list, e.g., Itm-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceList or Itm-CSI-NZP-CSI-RS-ResourceSet or Itm-CSI-RS-ResourceSet.

[0136] The reporting configuration, e.g., LTM-CSI-ReportConfig, may contain a configuration of report quantity set, e.g., reportQuantity, set to 'cri-RSRP’ to request / command the UE to report Ll-RSRP and CSI-RS resource indicator (CRI) for one or more CSI-RSs.

[0137] Then the first apparatus 110 may determine (715) a CSI-RS associated with a serving cell of the first apparatus 110 from the received measurement RS set based on a comparison of respective center frequencies of one or more CSI-RSs in the measurement RS set with respective further center frequencies of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific SSB of the serving cell.

[0138] That is, the center frequency of a CSI-RS in the measurement RS set may be used to determine its association with the current serving cell. The center frequency of the CSI-RS may be derived using one or more parameters such as frequency of point A, starting RB, number of RBs, sub carrier spacing, etc.

[0139] If the center frequency of the CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell. Additional condition matching cell ID may also be applied. If the center frequency of the CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell and a cell ID of a candidate cell associated with the CSI-RS matches afurther cell ID of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0140] In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList).In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.

[0141]

[0142] For example, if the center frequency of the CSI-RS from the measurement RS set is same as the further center frequency of the further CSI-RS configured in the current serving cell (along with the cell IDs), the CSI-RS may be considered as being associated with the serving cell.

[0143] In some other example embodiments, if a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured for a current active (BWP) in the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0144] In yet example embodiments, if a center frequency of a CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.

[0145] It is also possible that if a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, the first apparatus 110 may determine the CSI-RS is associated with the serving cell.The cell ID condition may also be considered for all options as described above. The cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of thecandidate cell linked to the corresponding candidate cell ID (e.g., provided by LTM-Candidateld). This candidate cell ID is indicated in the measurement resource configuration information alongside the set of CSI-RSs, where each CSI-RS in the set has a corresponding entry in the list of candidate cell IDs (e.g., given by Itm-CandidateldList). In some example embodiments, the cell ID of a candidate cell associated with a CSI-RS may be determined as the PCI of the candidate cell linked to the SSB determined from the QCL information of the CSI-RS.

[0146] Then the first apparatus 110 may report (720), to the second apparatus 120 based on the reporting configuration for the cell switch operation, a measurement at least associated with the determined CSI-RS. For example, the measurement may comprise a RSRP measurement, a SINR measurement and / or a SNR measurement. The first apparatus 110 may also measure, in addition to the determined CSI-RS associated with the serving cell, at least one other CSI-RS associated with at least one other candidate cell.

[0147] For example, if the reporting configuration indicates a measurement of at least one CSI-RS associated with the serving cell is to be reported, the first apparatus 110 may report, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0148] For the embodiments described above, two frequency values may be considered as matching with each other if they provide exactly the same value or fall within a specified range, i.e., within a given (configured or predefined) offset. For example, frequency 1 and frequency 2 are considered to match if frequency 1 = frequency 2 or if frequency 1 = frequency 2 ± offset.

[0149] Although a comparison of frequency information are focused in the embodiments described above. However, to determine whether a candidate CSI-RS belongs to the current serving cell, cell IDs (PCIs) may also be matched, as done for SSB-based measurements.

[0150] Different solutions for determining a CSI-RS from a measurement RS set associated with the serving cell have been described with reference to FIGS. 4-7. With reference to FIG. 8, more details will be further described as below.

[0151] Reference is now made to FIG. 8, which shows a signaling chart 800 of communication according to some example embodiments of the present disclosure. Asshown in FIG. 8, the signaling chart 800 involves a first apparatus 110 and a second apparatus 120, a serving cell 102 and a candidate cell 104. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 800.

[0152] In some example scenarios, the second apparatus 120 may be implemented as a centralized Unit (CU), which may manage the serving cell of the first apparatus (e.g., the cell 102 shown in FIG. 1). A further candidate cell 104 may also be managed by the second apparatus 120, or may be managed by a further RAN device (not shown).

[0153] As shown in FIG. 8, the first apparatus 110 may send (802, 804) a measurement report (e.g., a L3 measurement report) to the second apparatus 120 via serving cell 102 (e.g., a source DU) and the second apparatus 120 may decide (806) to prepare a handover (HO) for LTM. The second apparatus 120 may perform (808) an LTM preparation, e.g., by proceeding with the UE context setup / modification procedures.

[0154] During this procedure, the second apparatus 120 may collect the CSI-RS(s) information from each cell, prepare one or more measurement sets containing the CSI-RS(s) from multiple cells, and then send the prepared measurement sets to each cell.

[0155] Each cell then may provide one or more report configurations, and each report configuration may be linked with a measurement set configuration. A report configuration may indicate whether SpCelllnclusion is configured or not. Additionally, the report configuration may indicate report quantities to be reported, such as CRI and RSRP. Additionally, the report configuration may indicate the number of measurements (CRI and RSRP) to be reported, e.g., M number of measurements for each of L number of cells. When SpCelllnclusion, M number of measurements are reported for the current SpCell and then M number of measurements for each of other L-l candidate cells.

[0156] The second apparatus 120 may generate (810) an RRC reconfiguration message which may include measurement set configurations, e.g., in the common LTM config, LTM-Config, where each set contains one or more CSI-RSs IDs from one or more candidate cells.

[0157] In this example, the current source / serving cell (e.g., the serving cell 102) may also be configured as a candidate cell, therefore the CSI-RSs of the current serving cell may also be added in one or more measurement sets. For example, the measurement RS set may contain CSI-RSs from the serving cell 102 and the further candidate cell 104, andnrOfReportedRS -PerCell (M) = 4, nrOfReportedCells (L) = 2. The details of CSI-RSs configuration associated with each candidate cell may be given in respective LTM-Candidate IE (outside of the Itm-CandidateConfig).

[0158] Reporting configurations for the current serving cell (as well as for the other candidate cells for subsequent LTM) may be given in the ServingCellConfig of each cell. Each report config links to one measurement set, indicating which RSs to be measured and reported. At least one report configuration for the current serving cell may configure with SpCelllnclusion, which may configure the first apparatus 110 to report the current serving cell measurements as well.

[0159] As an example, the RRC reconfiguration message may also include an indication related to CSI-RS determination of the serving cell. That is, the second apparatus 120 may configure or indicate which of the proposed options (described with reference to FIGS. 4-7) is to be used to determine the CSI-RSs associated with the current serving cell when SpCelllnclusion is configured.

[0160] In this case, the indication related to CSI-RS determination of the serving cell may be included in or configured as part of the report configuration (e.g., LTM-CSI-ReportConfig) to align with reporting requirements.

[0161] As another option, this indication may also be included in the cell switch configuration (e.g., LTM Configuration). This indication may also be configured per candidate cell (e.g., within the LTM-candidate IE) to allow cell-specific behavior. With such cell-specific or report-specific configurations, each cell may determine / decide which option to use based on the CSI-RS configurations provided for LTM and the serving cell procedure. For example, if the CSI-RSs configured for LTM (e.g., provided in LTM-Candidate outside of Itm-CandidateConfig) are independent of the CSI-RSs configured for the serving cell procedure (e.g., within Itm-CandidateConfig), then CSI-RS determination of the serving cell using the SSB or CSI-RS determination of the serving cell using the frequency of Point A may be selected. Or, if the CSI-RSs configured for LTM are aligned or overlapping with those configured for the serving cell procedure, other options such as CSI-RS determination of the serving cell using the startingRB or the center frequency may be more suitable.

[0162] If this indication is absent, the rule (based on one of the proposed options) for determination may be specified. If absent, a default rule for CSI-RS determination may be applied.

[0163] Then the second apparatus 120 may send (812, 814) the RRC reconfiguration message to the first apparatus 110 via the serving cell 102.

[0164] The first apparatus 110 may send (816, 818) the RRCReconfigurationComplete message to the second apparatus 120 via the serving cell 102.

[0165] The first apparatus 110 may perform (820) the measurements on the CSI-RS given in the measurement set configured for the report config. Since the report configuration configures the SpCelllnclusion, the first apparatus 110 may determine (822) which CSI-RSs are associated with the current SPCelllnclsuion-as per the indication or specified rule, based on one of the options proposed in the previous section. Details of the determination of CSI-RS associated with the current serving have been described with reference to FIGS. 4-7, which may be omitted here.

[0166] Then the first apparatus 110 may prepare (824) a measurement report, at least containing the measurements from the current SpCell. The number of measurements (M) to be included may be based on the configuration given in the report configuration. If the number of reported cells (L) configured in the report configuration is above 1, the first apparatus 110 may include the M measurements for L-l candidate cells (other than the current SpCell) and then send (826) the report to the network.

[0167] The serving cell 120 may decide (828) to perform cell switch and send (830) a cell switch command to the first apparatus 110. Then the first apparatus 110 may perform (832) cell switch to the indicated target cell in the cell switch command.

[0168] According to the solution proposed in the present disclosure, the impact on the related specification may be as below:If a UE is configured with a Itm-CSI-ReportConfig,if the UE is configured with spCelllnclusion, the UE shall report in a single reporting instance nrOfReportedRS -PerCell different SSBRI or different CRI for the current SpCell and each of the nrOfReportedCells -1 candidate cells. Otherwise, the UE shall report in a single reporting instance nrOfReportedRS-PerCell different SSBRI or different CRI for each of the nrOfReportedCells candidate cells,where SSBRI k (k > 0) corresponds to the configured (k+l)-th entry of the associated Itm-CSI-SSB-ResourceList in the corresponding Itm-CSI-SSB-ResourceSet, if spCelllnclusion is configured, SSB resources in Itm-CSI-SSB-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (given by ssb-Frequency) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of cell-defining SSB of the current SpCell.where CRI k (k > 0) corresponds to the configured (k+l)-th entry of the associated Itm-CSI-NZP-CSI-RS-ResourceList in the corresponding Itm-CSI-NZP-CSI-RS-ResourceSet,if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (given by ssb-Frequency for the SSBs QCLed with NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of cell-defining SSB of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (absoluteFrequencyPointA) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and frequency associated with point A of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSLRS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (frequencies associated with the starting resource blocks of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and frequency of a starting resource block of any of the CSI-RSs of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSLRS-ResourceList associated with the current SpCell are the entries where PCI (givenby Itm-CandidatePCI) and frequency information (frequencies associated with the starting resource blocks of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and frequency of a starting resource block of any of the CSI-RSs in the active DL BWP of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (center frequencies associated of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of any of the CSI-RSs of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCI) and frequency information (center frequencies associated of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of any of the CSI-RSs in the active DL BWP of the current SpCell.

[0169] According to the solution proposed in the present disclosure, the impact on the related specification may be as below:A UE may be configured with a Itm-CSI-ReportConfig with the higher layer parameter reportQuantity set to either 'cri-RSRP' or 'ssb-Index-RSRP'.If a UE is configured with a Itm-CSI-ReportConfig with Itm-ReportConfigType is not set to ‘ [eventTriggered]’,if the UE is configured with spCelllnclusion with reportQuantity set to 'ssb-Index-RSRP' or when LTM-CSI-ResourceConfig contains configuration of a [Itm-CSI-SSB-ResourceSet], the UE shall report in a single reporting instance nrOfReportedRS-PerCell different SSBRI for the current SpCell and each of the nrOfReportedCells -1 candidate cells. Otherwise, the UE shall report in a single reporting instance nrOfReportedRS-PerCell different SSBRI for each of the nrOfReportedCells candidate cells,where SSBRI k (k > 0) corresponds to the configured (k+l)-th entry of theassociated Itm-CSI-SSB-ResourceList in the corresponding Itm-CSI-SSB-ResourceSet, if spCelllnclusion is configured, SSB resources in Itm-CSI-SSB-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCL) and frequency information (given by ssb-Frequency) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of cell-defining SSB of the current SpCell.if the UE is configured with spCelllnclusion with reportQuantity set to 'cri-Index- RSRP' or when LTM-CSI-ResourceConfig contains configuration of a Itm-CSI-NZP- CSI-RS-ResourceSel. the UE shall report in a single reporting instance nrOfReportedRS- PerCell different CRI for the current SpCell and each of the nrOfReportedCells -1 candidate cells. Otherwise, the UE shall report in a single reporting instance nrOfReportedRS-PerCell different CRI for each of the nrOfReportedCells candidate cells,where CRI k (k > 0) corresponds to the configured (k+l)-th entry of the associated Itm-CSI-NZP-CSI-RS-ResourceList in the corresponding Itm-CSI-NZP-CSI-RS-ResourceSet,if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCL) and frequency information (given by ssb-Frequency for the SSBs QCLed with NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of cell-defining SSB of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCL) and frequency information (absoluteFrequencyPointA) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and frequency associated with point A of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCL) and frequency information (frequencies associated with the startingresource blocks of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and frequency of a starting resource block of any of the CSI-RSs of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCP) and frequency information (frequencies associated with the starting resource blocks of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList') is equal to the PCI and frequency of a starting resource block of any of the CSI-RSs in the active DL BWP of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCP) and frequency information (center frequencies associated of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of any of the CSI-RSs of the current SpCell.if spCelllnclusion is configured, NZP-CSI-RS resources in Itm-CSI-NZP-CSI-RS-ResourceList associated with the current SpCell are the entries where PCI (given by Itm-CandidatePCP) and frequency information (center frequencies associated of NZP-CSI-RSs) of the candidate cell associated with the LTM-Candidateld (given by the corresponding entry in Itm-CandidateldList) is equal to the PCI and center frequency of any of the CSI-RSs in the active DL BWP of the current SpCell.

[0170] Based on the solution of the present disclosure, the UE is enabled to identify CSI-RSs associated with the current SpCell from the measurement RS set configured for cell switch measurements, when the UE is configured to report measurements for the current SpCell.

[0171] Moreover, the UE is enabled to use SpCelllnclusion feature when UE is configured with CSI-RS measurements. SpCelllnclusion aims to provide more information to the network for reliable LTM cell switch decision.

[0172] FIG. 9 shows a flowchart of an example method 900 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. Forthe purpose of discussion, the method 900 will be described from the perspective of the first apparatus 110 in FIG. 1.

[0173] At block 910, the first apparatus 110 receives a reporting configuration from a second apparatus.

[0174] At block 920, the first apparatus 110 receives, from the second apparatus, a configuration of a measurement reference signal, RS, set associated with the cell switch operation.

[0175] At block 930, the first apparatus 110 determines a channel state information RS, CSI-RS, associated with a serving cell of the first apparatus from the measurement RS set based at least on an association of a synchronization signal block, SSB, associated with the CSI-RS.

[0176] At block 940, the first apparatus 110 reports, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0177] In some example embodiments, the method 900 further comprises: in accordance with a determination that the association of the SSB with the CSI-RS is quasi-co-located (QCL), comparing a frequency of the SSB with a further frequency of a further SSB associated with the serving cell; and in accordance with a determination, determining on the comparison, that the frequency matches the further frequency, determining the CSI-RS is associated with the serving cell.

[0178] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0179] In some example embodiments, the further frequency refers to a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell.

[0180] In some example embodiments, the association indicated in QCL information that is associated with the CSI-RS.

[0181] In some example embodiments, an identifier of the SSB is indicated in the QCL information.

[0182] In some example embodiments, an identifier of the SSB is obtained based on an identifier of a transmission configuration indicator (TCI) state indicated in the QCLinformation which references the SSB associated with the TCI state.

[0183] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0184] In some example embodiments, the method 900 further comprises: receiving, from the second apparatus, an indication of determining the CSI-RS associated with the serving cell based on the SSB associated with the CSI-RS.

[0185] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0186] In some example embodiments, the method 900 further comprises: reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0187] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0188] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0189] FIG. 10 shows a flowchart of an example method 1000 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1000 will be described from the perspective of the first apparatus 110 in FIG. 1.

[0190] At block 1010, the first apparatus 110 receives a reporting configuration from a second apparatus.

[0191] At block 1020, the first apparatus 110 receives, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation.

[0192] At block 1030, the first apparatus 110 determines, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point.

[0193] At block 1040, the first apparatus 110 reports, to the second apparatus for the cellswitch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0194] In some example embodiments, the method 1000 further comprises: in accordance with a determination that an absolute frequency point of a CSI-RS in the measurement RS set matches the further absolute frequency point of the serving cell or the frequency corresponding to the further absolute frequency point, determining the CSI-RS is associated with the serving cell.

[0195] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0196] In some example embodiments, the absolute frequency point of the CSI-RS refers to absolute frequency point A which indicates an absolute frequency of a reference resource block.

[0197] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0198] In some example embodiments, the method 1000 further comprises: receiving, from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell by using the respective absolute frequency points of the one or more CSI-RSs in the measurement RS set.

[0199] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0200] In some example embodiments, the method 1000 further comprises: reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0201] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0202] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0203] FIG. 11 shows a flowchart of an example method 1100 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1100 will be described from the perspective of thefirst apparatus 110 in FIG. 1.

[0204] At block 1110, the first apparatus 110 receives a reporting configuration from a second apparatus.

[0205] At block 1120, the first apparatus 110 receives, from a second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation.

[0206] At block 1130, the first apparatus 110 determines, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective frequencies of starting resource blocks (RBs) of one or more CSI-RSs in the measurement RS set with respective further frequencies of further starting RBs of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific synchronization signal block (SSB) of the serving cell.

[0207] At block 1140, the first apparatus 110 reports, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0208] In some example embodiments, the method 1100 further comprises: in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in the serving cell, determining the CSI-RS is associated with the serving cell.

[0209] In some example embodiments, the method 1100 further comprises: in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in a current active bandwidth part (BWP) in the serving cell, determining the CSI-RS is associated with the serving cell.

[0210] In some example embodiments, the method 1100 further comprises: in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell, determining the CSI-RS is associated with the serving cell.

[0211] In some example embodiments, the method 1100 further comprises: in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configuredin the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, determining the CSI-RS is associated with the serving cell.

[0212] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0213] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0214] In some example embodiments, the method 1100 further comprises: receiving, from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell using at least the respective frequencies of the starting RBs of the one or more CSI-RSs in the measurement RS set.

[0215] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0216] In some example embodiments, the method 1100 further comprises: reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0217] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0218] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0219] FIG. 12 shows a flowchart of an example method 1200 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1200 will be described from the perspective of the first apparatus 110 in FIG. 1.

[0220] At block 1210, the first apparatus 110 receives a reporting configuration from a second apparatus.

[0221] At block 1220, the first apparatus 110 receives, from a second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation.

[0222] At block 1230, the first apparatus 110 determines, from the measurement RS set,a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective center frequencies of one or more CSI-RSs in the measurement RS set with respective further center frequencies of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific synchronization signal block (SSB) of the serving cell.

[0223] At block 1240, the first apparatus 110 reports, to the second apparatus for the cell switch operation based on the reporting configuration , a measurement at least associated with the determined CSI-RS.

[0224] In some example embodiments, the method 1200 further comprises: in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell, determining the CSI-RS is associated with the serving cell.

[0225] In some example embodiments, the method 1200 further comprises: in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured for a current active bandwidth part (BWP) in the serving cell, determining the CSI-RS is associated with the serving cell.

[0226] In some example embodiments, the method 1200 further comprises: in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell, determining the CSI-RS is associated with the serving cell.

[0227] In some example embodiments, the method 1200 further comprises: in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, determining the CSI-RS is associated with the serving cell.

[0228] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0229] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0230] In some example embodiments, the method 1200 further comprises: receiving,from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell using the respective center frequencies of one or more CSI-RSs in the measurement RS set.

[0231] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0232] In some example embodiments, the method 1200 further comprises: reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0233] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0234] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0235] In some example embodiments, a first apparatus capable of performing any of the method 900 (for example, the first apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 900. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the first apparatus 110 in FIG. 1.

[0236] In some example embodiments, the first apparatus comprises means for receiving a reporting configuration from a second apparatus; means for receiving, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; means for determining a channel state information RS (CSI-RS) associated with a serving cell of the first apparatus from the measurement RS set based at least on an association of a synchronization signal block (SSB) associated with the CSI-RS; and means for reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0237] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that the association of the SSB with the CSI-RS is quasi-co-located (QCL), comparing a frequency of the SSB with a further frequency of a further SSB associated with the serving cell; and means for in accordance with adetermination, determining on the comparison, that the frequency matches the further frequency, determine the CSI-RS is associated with the serving cell.

[0238] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0239] In some example embodiments, the further frequency refers to a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell.

[0240] In some example embodiments, the association indicated in QCL information that is associated with the CSI-RS.

[0241] In some example embodiments, an identifier of the SSB is indicated in the QCL information.

[0242] In some example embodiments, an identifier of the SSB is obtained based on an identifier of a transmission configuration indicator (TCI) state indicated in the QCL information which references the SSB associated with the TCI state.

[0243] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0244] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication of determining the CSI-RS associated with the serving cell based on the SSB associated with the CSI-RS.

[0245] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0246] In some example embodiments, the first apparatus further comprises: means for reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0247] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0248] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0249] In some example embodiments, a first apparatus capable of performing any of the method 1000 (for example, the first apparatus 110 in FIG. 1) may comprise means forperforming the respective operations of the method 1000. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the first apparatus 110 in FIG. 1.

[0250] In some example embodiments, the first apparatus comprises means for receiving a reporting configuration from a second apparatus; means for receiving, from the second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; means for determining, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective absolute frequency points of one or more CSI-RSs in the measurement RS set with a further absolute frequency point of a serving cell of the first apparatus or a frequency corresponding to the further absolute frequency point; and means for reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0251] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that an absolute frequency point of a CSI-RS in the measurement RS set matches the further absolute frequency point of the serving cell or the frequency corresponding to the further absolute frequency point, determining the CSI-RS is associated with the serving cell.

[0252] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0253] In some example embodiments, the absolute frequency point of the CSI-RS refers to absolute frequency point A which indicates an absolute frequency of a reference resource block.

[0254] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0255] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell by using the respective absolute frequency points of the one or more CSI-RSs in the measurement RS set.

[0256] In some example embodiments, the indication is received via a cell switchconfiguration or via the reporting configuration.

[0257] In some example embodiments, the first apparatus further comprises: means for reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0258] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0259] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0260] In some example embodiments, a first apparatus capable of performing any of the method 1100 (for example, the first apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 1100. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the first apparatus 110 in FIG. 1.

[0261] In some example embodiments, the first apparatus comprises means for receiving a reporting configuration from a second apparatus; means for receiving, from a second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; means for determining, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective frequencies of starting resource blocks (RBs) of one or more CSI-RSs in the measurement RS set with respective further frequencies of further starting RBs of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific synchronization signal block (SSB) of the serving cell; and means for reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0262] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in the serving cell, determining the CSI-RS is associated with the serving cell.

[0263] In some example embodiments, the first apparatus further comprises: means forin accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in a current active bandwidth part (BWP) in the serving cell, determining the CSI-RS is associated with the serving cell.

[0264] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell, determining the CSI-RS is associated with the serving cell.

[0265] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a frequency of a starting RB of a CSI-RS in the measurement RS set matches a further frequency of a further starting RB of a further CSI-RS configured in the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, determining the CSI-RS is associated with the serving cell.

[0266] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0267] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0268] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell using at least the respective frequencies of the starting RBs of the one or more CSI-RSs in the measurement RS set.

[0269] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0270] In some example embodiments, the first apparatus further comprises: means for reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0271] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0272] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0273] In some example embodiments, a first apparatus capable of performing any of the method 1200 (for example, the first apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 1200. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the first apparatus 110 in FIG. 1.

[0274] In some example embodiments, the first apparatus comprises means for receiving a reporting configuration from a second apparatus; means for receiving, from a second apparatus, a configuration of a measurement reference signal (RS) set associated with the cell switch operation; means for determining, from the measurement RS set, a channel state information RS (CSI-RS) associated with the serving cell based on a comparison of respective center frequencies of one or more CSI-RSs in the measurement RS set with respective further center frequencies of one or more further CSI-RSs configured in the serving cell or with a frequency of a specific synchronization signal block (SSB) of the serving cell; and means for reporting, to the second apparatus for the cell switch operation based on the reporting configuration, a measurement at least associated with the determined CSI-RS.

[0275] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell, determining the CSI-RS is associated with the serving cell.

[0276] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured for a current active bandwidth part (BWP) in the serving cell, determining the CSI-RS is associated with the serving cell.

[0277] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a center frequency of a cell-defining SSB or an absolute frequency SSB of the serving cell, determining the CSI-RS is associated with the servingcell.

[0278] In some example embodiments, the first apparatus further comprises: means for in accordance with a determination that a center frequency of a CSI-RS in the measurement RS set matches a further center frequency of a further CSI-RS configured in the serving cell and an absolute frequence point of the CSI-RS matches a further absolute frequence point of the further CSI-RS, determining the CSI-RS is associated with the serving cell.

[0279] In some example embodiments, a cell identifier of a candidate cell associated with the CSI-RS matches a further cell identifier of the serving cell.

[0280] In some example embodiments, the measurement RS set is indicated by a CSI-RS resource list.

[0281] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication of determining the at least one CSI-RS associated with the serving cell using the respective center frequencies of one or more CSI-RSs in the measurement RS set.

[0282] In some example embodiments, the indication is received via a cell switch configuration or via the reporting configuration.

[0283] In some example embodiments, the first apparatus further comprises: means for reporting, to the second apparatus based on the reporting configuration at least of a measurement result of the determined CSI-RS or an index of the determined CSI-RS.

[0284] In some example embodiments, the serving cell comprises at least one of a primary cell or a primary secondary cell.

[0285] In some example embodiments, the first apparatus comprises a terminal device and the second apparatus comprises a network device.

[0286] FIG. 13 is a simplified block diagram of a device 1300 that is suitable for implementing example embodiments of the present disclosure. The device 1300 may be provided to implement a communication device, for example, the first apparatus 110 or the second apparatus 120 as shown in FIG. 1. As shown, the device 1300 includes one or more processors 1310, one or more memories 1320 coupled to the processor 1310, and one or more communication modules 1340 coupled to the processor 1310.

[0287] The communication module 1340 is for bidirectional communications. The communication module 1340 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 1340 may include at least one antenna.

[0288] The processor 1310 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1300 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[0289] The memory 1320 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 1324, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), an optical disk, a laser disk, and other magnetic storage and / or optical storage. Examples of the volatile memories include, but are not limited to, a random-access memory (RAM) 1322 and other volatile memories that will not last in the power-down duration.

[0290] A computer program 1330 includes computer executable instructions that are executed by the associated processor 1310. The instructions of the program 1330 may include instructions for performing operations / acts of some example embodiments of the present disclosure. The program 1330 may be stored in the memory, e.g., the ROM 1324. The processor 1310 may perform any suitable actions and processing by loading the program 1330 into the RAM 1322.

[0291] The example embodiments of the present disclosure may be implemented by means of the program 1330 so that the device 1300 may perform any process of the disclosure as discussed with reference to FIG. 2 to FIG. 12. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0292] In some example embodiments, the program 1330 may be tangibly contained in acomputer readable medium which may be included in the device 1300 (such as in the memory 1320) or other storage devices that are accessible by the device 1300. The device 1300 may load the program 1330 from the computer readable medium to the RAM 1322 for execution. In some example embodiments, the computer readable medium may include any types of non-transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

[0293] FIG. 14 shows an example of the computer readable medium 1400 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 1400 has the program 1330 stored thereon.

[0294] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. Although various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0295] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non-transitory computer readable medium. The computer program product includes computerexecutable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[0296] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[0297] In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[0298] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0299] Further, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, although several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separatelyor in any suitable sub-combination.

[0300] Although the present disclosure has been described in languages specific to structural features and / or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

52WHAT IS CLAIMED IS:

1. A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to:acquire, from a second apparatus, a control policy for measurement reporting during a cell transition;detect, from the second apparatus, a collection of reference signal (RS) identifiers assigned to the cell transition;isolate a channel state information RS (CSI-RS) pertaining to a serving cell from the collection of RS identifiers, where the isolation is performed using a spatial correlation of a synchronization signal block (SSB) that is linked to the CSI-RS; andrelay, to the second apparatus, a measured value for the isolated CSI-RS in accordance with the control policy.

2. The first apparatus of claim 1, wherein the instructions cause the first apparatus to:detect that the spatial correlation between the SSB and the CSI-RS is quasi-colocated (QCL);in response to detecting the QCL spatial correlation, execute a comparison between a frequency of the SSB and a reference frequency of another SSB linked to the serving cell;validate that the frequency of the SSB aligns with the reference frequency; and based on the validation, catalog the CSI-RS as being affiliated with the serving cell.

3. The first apparatus of claim 2, wherein the first apparatus is caused to authenticate that a cell descriptor of a candidate source linked to the CSI-RS aligns with a separate cell descriptor of the serving cell.

4. The first apparatus of claim 2, wherein the reference frequency corresponds to a primary center frequency of a cell-defining SSB or an absolute frequency coordinate of the serving cell.

535. The first apparatus of claim 1, wherein the spatial correlation is defined within spatial parameter metadata (QCL information) linked to the CSI-RS.

6. The first apparatus of claim 5, wherein a label for the SSB is embedded within the spatial parameter metadata.

7. The first apparatus of claim 5, wherein the instructions cause the first apparatus to extract a label for the SSB by referencing a transmission state index (TCI state) specified in the metadata.

8. The first apparatus of claim 1, wherein the collection of RS identifiers is signaled through a CSI-RS resource registry.

9. The first apparatus of claim 1, wherein the instructions cause the first apparatus to process a specific command received from the second apparatus to perform the isolation of the CSI-RS utilizing the SSB linked to the CSI-RS.

10. The first apparatus of claim 9, wherein the command is conveyed through a handover setup or the control policy.

11. The first apparatus of claim 1, wherein the instructions cause the first apparatus to:recognize that the control policy designates that data for at least one CSI-RS belonging to the serving cell is required; andin response to the recognition, relay at least one of a signal strength value for the isolated CSI-RS or a resource index of the isolated CSI-RS.

12. The first apparatus of claim 1, wherein the serving cell is characterized as a primary cell (PCell) or a primary secondary cell (PSCell).

13. The first apparatus of claim 1, wherein the first apparatus comprises a user equipment (UE) and the second apparatus comprises a base station.5414. A method comprising:acquiring, from a second apparatus, a control policy for measurement reporting during a cell transition;detecting, from the second apparatus, a collection of reference signal (RS) identifiers assigned to the cell transition;isolating a channel state information RS (CSI-RS) pertaining to a serving cell from the collection of RS identifiers, where the isolation is performed using a spatial correlation of a synchronization signal block (SSB) that is linked to the CSI-RS; andrelaying, to the second apparatus, a measured value for the isolated CSI-RS in accordance with the control policy.

15. A first apparatus comprising:means for acquiring, from a second apparatus, a control policy for measurement reporting during a cell transition;means for detecting, from the second apparatus, a collection of reference signal (RS) identifiers assigned to the cell transition;means for isolating a channel state information RS (CSI-RS) pertaining to a serving cell from the collection of RS identifiers, where the isolation is performed using a spatial correlation of a synchronization signal block (SSB) that is linked to the CSI-RS; andmeans for relaying, to the second apparatus, a measured value for the isolated CSI-RS in accordance with the control policy.

16. A computer readable medium comprising instructions stored thereon for causing an apparatus at least to perform the method of claim 14.

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